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Pienkowski M, Chaiton M, Bondy SJ, Cohen JE, Dubray J, Eissenberg T, Kaufman P, Stanbrook MB, O'Loughlin J, Dos Santos J, Schwartz R. Milestones in the natural course of the onset of e-cigarette dependence among adolescents and young adults: Retrospective study. Addict Behav 2024; 148:107846. [PMID: 37678007 DOI: 10.1016/j.addbeh.2023.107846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 08/24/2023] [Accepted: 08/30/2023] [Indexed: 09/09/2023]
Abstract
INTRODUCTION There is considerable controversy about the development of dependence among e-cigarette users. This study describes the average amount of time using e-cigarettes before dependence milestones emerge and the differences in developing dependence between e-cigarette users who smoke cigarettes compared to those who do not. METHODS Adolescents and young adults aged 16-25 living in Canada were recruited into an online survey in 2021. Current (past-month) e-cigarette users completed 15 items assessing dependence from the Penn-State Electronic Cigarette Dependence Index and the E-cigarette Dependence Scale for a total of 12 behavioural (e.g., difficulty refraining from vaping) and 3 frequency (e.g., using e-cigarette daily, weekly, or monthly) indicators of dependence milestones. Number of years after e-cigarette onset at which the cumulative probability of attaining each milestone was 25 % was computed. RESULTS Among 1205 participants, most (80.6 %) were female, 73.7 % were Caucasian, and 49.7 % resided in Ontario. Ten of the 12 e-cigarette use milestones were attained by 25 % of respondents 2 years after starting vaping except for daily cigarette use (2.5 years after onset) and waking at night to vape (5.6 years after onset). Within the entire study population, frequency milestones (weekly, monthly, daily e-cigarette use) were attained faster by ever-smokers (hazard ratio compared to attainment by never-smokers: 1.12, 1.21, and 1.28 respectively), whereas for at least monthly users, behavioural milestones were attained faster by never-smokers. DISCUSSION Many current e-cigarette users developed symptoms of e-cigarette dependence between two and five years since onset. Never smokers may be at higher risk of becoming e-cigarette dependent since they attained e-cigarette dependence milestones faster than smokers.
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Affiliation(s)
- M Pienkowski
- Dalla Lana School of Public Health, University of Toronto, Canada
| | - M Chaiton
- Dalla Lana School of Public Health, University of Toronto, Canada; Centre for Addiction and Mental Health, Toronto, Canada.
| | - S J Bondy
- Dalla Lana School of Public Health, University of Toronto, Canada
| | - J E Cohen
- Dalla Lana School of Public Health, University of Toronto, Canada; Institute for Global Tobacco Control, Department of Health, Behavior and Society, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - J Dubray
- Dalla Lana School of Public Health, University of Toronto, Canada
| | - T Eissenberg
- Center for the Study of Tobacco Products, Department of Psychology, Virginia Commonwealth University, Richmond, VA, USA
| | - P Kaufman
- Dalla Lana School of Public Health, University of Toronto, Canada
| | - M B Stanbrook
- Division of Respirology, Department of Medicine, University of Toronto, Canada
| | - J O'Loughlin
- School of Public Health, University of Montreal, Montreal, QC, Canada
| | - J Dos Santos
- Dalla Lana School of Public Health, University of Toronto, Canada
| | - R Schwartz
- Dalla Lana School of Public Health, University of Toronto, Canada; Centre for Addiction and Mental Health, Toronto, Canada
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Rezende MS, Santos JTCD, Santos SO, Santos JD, Silva NL, Pinheiro CS, Araújo AAS, Martins-Filho PRS, Quintans-Júnior LJ, Schimieguel DM. RELAÇÃO ENTRE PERFIL HEMATOLÓGICO E AS COMORBIDADES EM PACIENTES ASSINTOMÁTICOS E SINTOMÁTICOS LEVES COM COVID-19 EM SERGIPE. Hematol Transfus Cell Ther 2022. [DOI: 10.1016/j.htct.2022.09.1132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Kim J, Chua M, Van Miegham T, Dos Santos J, Mackay E, Erdman L, Skreta M, Keefe D, Lolas M, Yadav P, Lorenzo A, Rickard M. Configuration and validation of the Toronto nomogram of antenatal ultrasound index generated from Bayesian meta-regression analysis in predicting Posterior Urethral Valves (PUV). Eur Urol 2022. [DOI: 10.1016/s0302-2838(22)00726-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Kim J, De Jesus M, Dos Santos J, Dy J, Ming J, Rickard M, Lorenzo A, Chua M. Beta-3 adrenoceptor agonist for the treatment of bladder dysfunction in children: A systematic review and meta-analysis. Eur Urol 2022. [DOI: 10.1016/s0302-2838(22)00732-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Oliveira JA, Silva NL, Silva DN, Santos SO, Santos JD, Lobão EVF, Santos DJGD, Araújo AAS, Júnior LJQ, Lima DMSM. PERFIL LEUCOCITÁRIO DOS INDIVÍDUOS POSITIVOS NA SOROLOGIA PARA O SARS-COV-2. Hematol Transfus Cell Ther 2021. [PMCID: PMC8530666 DOI: 10.1016/j.htct.2021.10.884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Objetivos A COVID-19, oriunda do novo coronavírus (SARS-CoV-2) se espalhou como uma pandemia, causando mais de 4 milhão de mortes globalmente, tornando-se uma emergência de saúde pública. O número de casos de pacientes recuperados é crescente, o que pode ser crucial sobre o curso da doença. Na forma grave da doença é possível observar linfopenia e leucopenia. Estes achados podem ser auxiliares como indicadores clínicos para avaliação e progressão da doença. Desta forma, este trabalho teve como objetivo descrever o perfil leucocitário dos indivíduos positivos na sorologia para o SARS-CoV-2. Material e métodos Trata-se de um estudo prospectivo em que indivíduos adultos de ambos os sexos, participantes do projeto EpiSergipe e que apresentaram resultado positivo ao teste rápido para IgG/IgM confirmado por sorologia. Foram coletadas amostras de sangue periférico para realização do hemograma e análise sorológica utilizando o kit comercial de imunoensaio fluorescente (IchromaTM COVID-19 Ab) em que os procedimentos foram realizados de acordo com as recomendações do fabricante. Resultados Foram analisadas amostras de 847 pacientes com sorologia positiva para o SARS-CoV-2, assintomáticos ou com sintomas leves, sendo 275 do sexo masculino (32,47%) e 572 do sexo feminino (67,53%). Do total de hemogramas analisados, 9,33% apresentaram leucocitose e 2,01% leucopenia (média leucócitos totais = 7.370/mm3 /±2,10). A linfocitose foi observada em 23,61% dos indivíduos e a linfopenia foi observada em apenas 1,18% (média linfócitos = 2.550/mm3/±772). A neutrofilia foi observada em 5,90% dos participantes e a neutropenia em 5,31% (média neutrófilos = 4.280/mm3/±1,67). A maioria dos hemogramas analisados (67,41%) apresentaram todos os parâmetros normais. Discussão A linfocitose, de acordo com estudos, pode auxiliar na previsão e acompanhamento da progressão da COVID-19, neste estudo foi observada em 23,61% dos hemogramas analisados, enfatizando que os participantes do presente estudo eram assintomáticos e sintomáticos leves, o que pode justificar o porquê grande parte dos pacientes apresentaram parâmetros dentro da normalidade. Além disso um estudo publicado em 2021, comparou os achados hematológicos de óbitos por COVID-19 com os de sobreviventes, nos indivíduos que morreram havia maior contagem de neutrófilos e leucócitos, e uma diminuição nos linfócitos, quando comparados aos sobreviventes. Neste estudo, não houveram óbitos, as taxas encontradas de leucocitose e neutrofilia foram de 9,33% e 5,90% respectivamente, e a linfopenia 1,18%. Conclusão A partir dos resultados prévios encontrados, observa-se alterações no perfil leucocitário em indivíduos com COVID-19, condizentes com os descritos recentemente na literatura.
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Pinto PO, Branquinho MV, Caseiro AR, Sousa AC, Brandão A, Pedrosa SS, Alvites RD, Campos JM, Santos FL, Santos JD, Mendonça CM, Amorim I, Atayde LM, Maurício AC. The application of Bonelike® Poro as a synthetic bone substitute for the management of critical-sized bone defects - A comparative approach to the autograft technique - A preliminary study. Bone Rep 2021; 14:101064. [PMID: 33981810 PMCID: PMC8082556 DOI: 10.1016/j.bonr.2021.101064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/16/2021] [Accepted: 04/05/2021] [Indexed: 12/26/2022] Open
Abstract
The effective treatment of non-unions and critical-sized defects remains a challenge in the orthopedic field. From a tissue engineering perspective, this issue can be addressed through the application bioactive matrixes to support bone regeneration, such as Bonelike®, as opposed to the widespread autologous grafting technique. An improved formulation of Bonelike® Poro, was assessed as a synthetic bone substitute in an ovine model for critical-sized bone defects. Bone regeneration was assessed after 5 months of recovery through macro and microscopic analysis of the healing features of the defect sites. Both the application of natural bone graft or Bonelike® Poro resulted in bridging of the defects margins. Untreated defect remained as fibrous non-unions at the end of the study period. The characteristics of the newly formed bone and its integration with the host tissue were assessed through histomorphometric and histological analysis, which demonstrated Bonelike® Poro to result in improved healing of the defects. The group treated with synthetic biomaterial presented bone bridges of increased thickness and bone features that more closely resembled the native spongeous and cortical bone. The application of Bonelike® Poro enabled the regeneration of critical-sized lesions and performed comparably to the autograph technique, validating its octeoconductive and osteointegrative potential for clinical application as a therapeutic strategy in human and veterinary orthopedics.
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Affiliation(s)
- P O Pinto
- Veterinary Clinics Department, Abel Salazar Biomedical Sciences Institute (ICBAS), University of Porto (UP), Rua de Jorge Viterbo Ferreira, nº 228, 4050-313, Porto, Portugal.,Animal Science Studies Centre (CECA), Agroenvironment, Technologies and Sciences Institute (ICETA), University of Porto, Rua D. Manuel II, Apartado 55142, 4051-401 Porto, Portugal.,Vasco da Gama Research Center (CIVG), Vasco da Gama University School (EUVG), Av. José R. Sousa Fernandes 197, Campus Universitário, Lordemão, 3020-210 Coimbra, Portugal
| | - M V Branquinho
- Veterinary Clinics Department, Abel Salazar Biomedical Sciences Institute (ICBAS), University of Porto (UP), Rua de Jorge Viterbo Ferreira, nº 228, 4050-313, Porto, Portugal.,Animal Science Studies Centre (CECA), Agroenvironment, Technologies and Sciences Institute (ICETA), University of Porto, Rua D. Manuel II, Apartado 55142, 4051-401 Porto, Portugal
| | - A R Caseiro
- Animal Science Studies Centre (CECA), Agroenvironment, Technologies and Sciences Institute (ICETA), University of Porto, Rua D. Manuel II, Apartado 55142, 4051-401 Porto, Portugal.,Vasco da Gama Research Center (CIVG), Vasco da Gama University School (EUVG), Av. José R. Sousa Fernandes 197, Campus Universitário, Lordemão, 3020-210 Coimbra, Portugal
| | - A C Sousa
- Veterinary Clinics Department, Abel Salazar Biomedical Sciences Institute (ICBAS), University of Porto (UP), Rua de Jorge Viterbo Ferreira, nº 228, 4050-313, Porto, Portugal.,Animal Science Studies Centre (CECA), Agroenvironment, Technologies and Sciences Institute (ICETA), University of Porto, Rua D. Manuel II, Apartado 55142, 4051-401 Porto, Portugal
| | - A Brandão
- Biosckin, Molecular and Cell Therapies, SA, Parque de Ciência e Tecnologia da Maia, Rua Eng. Frederico Ulrich, 2650, 4470-605 Moreira da Maia, Portugal
| | - S S Pedrosa
- Animal Science Studies Centre (CECA), Agroenvironment, Technologies and Sciences Institute (ICETA), University of Porto, Rua D. Manuel II, Apartado 55142, 4051-401 Porto, Portugal
| | - R D Alvites
- Veterinary Clinics Department, Abel Salazar Biomedical Sciences Institute (ICBAS), University of Porto (UP), Rua de Jorge Viterbo Ferreira, nº 228, 4050-313, Porto, Portugal.,Animal Science Studies Centre (CECA), Agroenvironment, Technologies and Sciences Institute (ICETA), University of Porto, Rua D. Manuel II, Apartado 55142, 4051-401 Porto, Portugal
| | - J M Campos
- Animal Science Studies Centre (CECA), Agroenvironment, Technologies and Sciences Institute (ICETA), University of Porto, Rua D. Manuel II, Apartado 55142, 4051-401 Porto, Portugal.,Vasco da Gama Research Center (CIVG), Vasco da Gama University School (EUVG), Av. José R. Sousa Fernandes 197, Campus Universitário, Lordemão, 3020-210 Coimbra, Portugal
| | - F L Santos
- Veterinary Clinics Department, Abel Salazar Biomedical Sciences Institute (ICBAS), University of Porto (UP), Rua de Jorge Viterbo Ferreira, nº 228, 4050-313, Porto, Portugal.,Animal Science Studies Centre (CECA), Agroenvironment, Technologies and Sciences Institute (ICETA), University of Porto, Rua D. Manuel II, Apartado 55142, 4051-401 Porto, Portugal
| | - J D Santos
- Network of Chemistry and Technology - Associated Laboratory for Green Chemistry (REQUIMTE-LAQV), Department of Metallurgy and Materials, Faculty of Engineering, University of Porto, Rua Dr Roberto Frias s/n, 4200-465 Porto, Portugal
| | - C M Mendonça
- Veterinary Clinics Department, Abel Salazar Biomedical Sciences Institute (ICBAS), University of Porto (UP), Rua de Jorge Viterbo Ferreira, nº 228, 4050-313, Porto, Portugal.,Animal Science Studies Centre (CECA), Agroenvironment, Technologies and Sciences Institute (ICETA), University of Porto, Rua D. Manuel II, Apartado 55142, 4051-401 Porto, Portugal
| | - I Amorim
- Department of Pathology and Molecular Immunology, Abel Salazar Institute of Biomedical Sciences (ICBAS), University of Porto (UP), Rua Jorge Viterbo Ferreira, n ° 228, 4050-313 Porto, Portugal.,Institute of Research and Innovation in Health (i3S), University of Porto (UP), Rua Alfredo Allen, 4200-135 Porto, Portugal
| | - L M Atayde
- Veterinary Clinics Department, Abel Salazar Biomedical Sciences Institute (ICBAS), University of Porto (UP), Rua de Jorge Viterbo Ferreira, nº 228, 4050-313, Porto, Portugal.,Animal Science Studies Centre (CECA), Agroenvironment, Technologies and Sciences Institute (ICETA), University of Porto, Rua D. Manuel II, Apartado 55142, 4051-401 Porto, Portugal
| | - A C Maurício
- Veterinary Clinics Department, Abel Salazar Biomedical Sciences Institute (ICBAS), University of Porto (UP), Rua de Jorge Viterbo Ferreira, nº 228, 4050-313, Porto, Portugal.,Animal Science Studies Centre (CECA), Agroenvironment, Technologies and Sciences Institute (ICETA), University of Porto, Rua D. Manuel II, Apartado 55142, 4051-401 Porto, Portugal
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Chaves PS, Dos Santos J, Pohlmann AR, Guterres SS, Beck RCR. Sublingual tablets containing spray-dried carvedilol-loaded nanocapsules: development of an innovative nanomedicine. Pharm Dev Technol 2020; 25:1053-1062. [DOI: 10.1080/10837450.2020.1785498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- P. S. Chaves
- Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - J. Dos Santos
- Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - A. R. Pohlmann
- Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
- Departamento de Química Orgânica, Instituto de Química, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - S. S. Guterres
- Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - R. C. R. Beck
- Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
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Dos Santos J, Fernandes P, Rocha Goncalves F, Pereira Rodrigues P, Ribeiro J, Goncalves A. P1349 POCUS by general and family physician - advancing physical examination. Eur Heart J Cardiovasc Imaging 2020. [DOI: 10.1093/ehjci/jez319.785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
BACKGROUND
Alongside with the development of hand held equipment, echo is becoming more accessible to nontraditional settings. General and family medicine (GPs) are at the forefront of any health system, but the use of cardiac echo by GPs is still unexplored. PURPOSE: This study aims to evaluate the accuracy of echocardiography assessment performed as an extension of the physical exam by GPs. METHODS: Two GPs underwent standard echocardiography training for 6 months. Subsequently, patients with diabetes or arterial hypertension were submitted to an echocardiogram performed by their GPs using a pocket ultrasound. Views obtained (with and without color Doppler) were parasternal long and short axis, apical and subcostal, with measurements of the posterior wall (PW), interventricular septum (IVS), left ventricle (LV), left atrium (LA), aorta and inferior vena cava (IVC). Studies were reviewed at the workstation and measured by two experts who classified the exams according to the image quality. RESULTS: Sixty echocardiograms were analyzed (mean age of 61y, 42% females and 58% males). In 50% the image quality was considered sufficient, 42% considered good and 8% considered bad. There were statistically significant differences between the GPs and expert measurements on the sinus of Valsalva (30.3 ± 3 to 28.8 ± 3.1mm, p = 0.001), LV in systole (p < 0.001, 28[24,31] for 31[29,34]mm), IVS (p = 0.001, 10.9 ± 1.7 for 10.1 ± 1.5mm), PW (p = 0.018, 8.7 ± 1.1 to 9.2 ± 1.6mm) and TAPSE (p = 0.021, 20.9 ± 2.3 to 20.1 ± 2.7mm). There were no significate differences in the measurements of the ascending aorta, LA, LV in diastole and IVC. Agreement between the GPs and the experts was moderate for the evaluation of LVH (k = 0.48). The concordance was substantial for evaluation of LV function (k = 0.66) and excellent for evaluation of pericardial effusion (k = 1) and right ventricular function (k = 1). Concordance was excellent for mitral insufficiency (k = 0.83) and substantial for aortic insufficiency (k = 0.68) and tricuspid insufficiency (k = 0.61). A case of mitral stenosis was identified by both. GPs signalized a case of mild aortic stenosis that the expert did not consider. CONCLUSION: GPs trained in echocardiography, using pocket ultrasound, can obtain cardiac images with sufficient quality for interpretation by experts in the majority of cases. In this study, differences in dimensions might be explained by interobserver variability and/or by the performance of measurements in different environments, mobile vs workstation. Overall the differences were minor and clinically meaningless.
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Affiliation(s)
- J Dos Santos
- Faculty of Medicine University of Porto, Department of Medicine, Porto, Portugal
| | - P Fernandes
- Faculty of Medicine University of Porto, Department of Medicine, Porto, Portugal
| | - F Rocha Goncalves
- Faculty of Medicine University of Porto, Department of Medicine, Porto, Portugal
| | | | - J Ribeiro
- Hospital Center of Vila Nova de Gaia/Espinho, Thorax and circulation unit, Vila Nova de Gaia, Portugal
| | - A Goncalves
- Faculty of Medicine University of Porto, Department of Medicine, Porto, Portugal
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Francis J, Fairhurst H, Kaethner A, Whalley G, Ryan C, Dos Santos J, Reeves B, Wheaton G, Horton A, Marangou J, Francis L, Hardefeldt H, Davis K, Engelman D, Remenyi B. P3133Single parasternal long axis echocardiography by briefly trained health workers using handheld devices for detection of rheumatic heart disease: a prospective study of diagnostic accuracy. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz745.0208] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Introduction
Echocardiographic screening can detect rheumatic heart disease (RHD) in high-risk populations,but is limited by reliance on highly-trained experts and equipment. We sought to determine the diagnostic utility of an ultra-abbreviated single parasternal-long-axis-sweep of the heart (SPLASH) echocardiography protocol to detect RHD, performed by briefly-trained health workers.
Methods
In Timor-Leste and Northern Australia, individuals aged 5–20y were offered school-based echocardiographic screening. Health workers completed online modules followed by one-week of practical training, logging 50 echocardiograms prior to study. The index test was SPLASH, performed and reported by health workers using handheld GE V-scan devices. The index test was abnormal if any mitral or aortic regurgitation was detected. The reference test was a comprehensive echocardiogram, performed by an echocardiographers or cardiologist on a GE Vivid-Q, reported according to World Heart Federation criteria. The diagnostic accuracy of the index test was determined.
Results
2590 subjects underwent index and reference tests. Prevalence of definite RHD was 3.2% (83/2590). Sensitivity and specificity of index test were 0.75 (95% CI 0.64–0.83) and 0.77 (95% CI 0.75–0.78) respectively for detection of any definite RHD, and 0.91 (95% CI 0.74–0.98) and 0.76 (95% CI 0.74–0.78) respectively for detection of moderate or severe RHD.
Conclusion
Health workers using SPLASH detected the vast majority of moderate and severe RHD cases, but lacked sensitivity for detection of mild RHD. Further analysis is underway to evaluate the learning curve and other performance indicators of health workers performing and interpreting echocardiograms. This will allow refinement of SPLASH protocol and augmentation of health worker training to increase detection rates and accuracy for future population screening initiatives.
Acknowledgement/Funding
Heart Foundation Australia Vanguard Grant, Menzies HOT-NORTH pilot project grant, Snow Foundation, Rotary, Bawinanga Aboriginal Corporation, Mala'la
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Affiliation(s)
- J Francis
- Menzies School of Health Research, Darwin, Australia
| | - H Fairhurst
- Menzies School of Health Research, Darwin, Australia
| | | | - G Whalley
- University of Otago, Division of Health Sciences, Otago, New Zealand
| | - C Ryan
- Maningrida Health Centre, Darwin, Australia
| | | | - B Reeves
- Cairns Hospital, Cairns, Australia
| | - G Wheaton
- Women's and Children's Hospital, Adelaide, Australia
| | - A Horton
- Monash University, Melbourne, Australia
| | | | - L Francis
- Royal Darwin Hospital, Department of Paediatrics, Darwin, Australia
| | - H Hardefeldt
- Royal Darwin Hospital, Department of Paediatrics, Darwin, Australia
| | - K Davis
- Royal Darwin Hospital, Department of Paediatrics, Darwin, Australia
| | - D Engelman
- Murdoch Children's Research Institute, Melbourne, Australia
| | - B Remenyi
- Menzies School of Health Research, Darwin, Australia
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Naoum NK, Chua ME, Ming JM, Santos JD, Saunders MA, Lopes RI, Koyle MA, Farhat WA. Return to emergency department after pediatric urology procedures. J Pediatr Urol 2019; 15:42.e1-42.e6. [PMID: 30527684 DOI: 10.1016/j.jpurol.2018.10.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Accepted: 10/26/2018] [Indexed: 10/27/2022]
Abstract
BACKGROUND Unplanned postoperative return visits to the emergency department (ED) and readmission represent a quality bench outcome and pose a considerable cost burden to health-care systems. OBJECTIVE The aim of this study is to evaluate ED return visits after pediatric urology procedures in a tertiary care children's hospital, trying to identify potential causes. This may constitute a platform for future improvement areas. MATERIALS AND METHODS A Quality Board-approved retrospective study was performed identifying all urologic cases completed between October 2012 and September 2015. Baseline demographics, American Society of Anesthesia class, operating surgeon, type of admission, type and duration of surgical procedure, and type of anesthesia given were evaluated. Patients who returned to the ED within 30 days of the surgery date were identified. The ED records were reviewed for time of return, etiology for visit, and management received. Univariate and subsequent multivariate logistic regression statistical analyses were performed to identify variables associated with ED return. Odds ratio (OR) and 95% confidence intervals (95% CIs) were generated to determine the significance of relationships. RESULTS Total of 4125 cases was identified. Median age was 32.9 months, with 85.1% of them being male. 349 (8.5%) cases returned to the ED within 30 days of the surgery. The majority of the returned patients, 295 (84.5%), managed conservatively with medications or reassurance, whereas 54 (15.5%) required readmission, and of those readmitted, 15 (4.3%) cases needed further surgical interventions, mainly urinary tract drainage procedures. Multivariate logistic regression analysis identified that the age, residence, admission type, inguinoscrotal surgery, and duration of surgical procedure were significantly associated with ED return (Table). The most common reason for the ED visit was UTI in 17.2%, followed by stent and catheter issues in 14.3%, wound-related in 14.3%, and bleeding in 11.7%. DISCUSSION Pediatric literature show varying rates of ED return ranging from 2.4% to 2.6% after urologic procedures. Our return to ED rate exceeds that found in US studies, which can perhaps be attributed to the differences between the Canadian and US health-care systems. As found with other studies, age, inpatient admission, procedure type, and increased operative time were related to ED returns, possibly because of the difficulty of young children expressing themselves and the presumed complex nature of longer operations that mostly need inpatient admission. The most common reason for ED return in this study as in others was presumptive UTI. A known limitation of this study is its retrospective nature, along with the possible missed visits of patients who presented to outside hospitals. CONCLUSION We present an account of the status of ED return visits after pediatric urology procedures in our institute. The majority of ED returns can be managed conservatively and are probably preventable.
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Affiliation(s)
- N K Naoum
- Division of Urology, The Hospital for Sick Children-Toronto, Canada.
| | - M E Chua
- Division of Urology, The Hospital for Sick Children-Toronto, Canada
| | - J M Ming
- Division of Urology, The Hospital for Sick Children-Toronto, Canada
| | - J D Santos
- Division of Urology, The Hospital for Sick Children-Toronto, Canada
| | - M A Saunders
- Division of Urology, The Hospital for Sick Children-Toronto, Canada
| | - R I Lopes
- Division of Urology, The Hospital for Sick Children-Toronto, Canada
| | - M A Koyle
- Division of Urology, The Hospital for Sick Children-Toronto, Canada
| | - W A Farhat
- Division of Urology, The Hospital for Sick Children-Toronto, Canada
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Campos JM, Sousa AC, Caseiro AR, Pedrosa SS, Pinto PO, Branquinho MV, Amorim I, Santos JD, Pereira T, Mendonça CM, Afonso A, Atayde LM, Maurício AC. Dental pulp stem cells and Bonelike ® for bone regeneration in ovine model. Regen Biomater 2018; 6:49-59. [PMID: 30740242 PMCID: PMC6362823 DOI: 10.1093/rb/rby025] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 10/01/2018] [Accepted: 10/23/2018] [Indexed: 12/22/2022] Open
Abstract
Development of synthetic bone substitutes has arisen as a major research interest in the need to find an alternative to autologous bone grafts. Using an ovine model, the present pre-clinical study presents a synthetic bone graft (Bonelike®) in combination with a cellular system as an alternative for the regeneration of non-critical defects. The association of biomaterials and cell-based therapies is a promising strategy for bone tissue engineering. Mesenchymal stem cells (MSCs) from human dental pulp have demonstrated both in vitro and in vivo to interact with diverse biomaterial systems and promote mineral deposition, aiming at the reconstruction of osseous defects. Moreover, these cells can be found and isolated from many species. Non-critical bone defects were treated with Bonelike® with or without MSCs obtained from the human dental pulp. Results showed that Bonelike® and MSCs treated defects showed improved bone regeneration compared with the defects treated with Bonelike® alone. Also, it was observed that the biomaterial matrix was reabsorbed and gradually replaced by new bone during the healing process. We therefore propose this combination as an efficient binomial strategy that promotes bone growth and vascularization in non-critical bone defects.
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Affiliation(s)
- J M Campos
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, no 228, Porto, Portugal.,Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, Portugal.,Escola Universitária Vasco da Gama (EUVG), Hospital Veterinário Universitário de Coimbra (HVUC), Campo Universitário - Bloco B, Lordemão, Coimbra, Portugal
| | - A C Sousa
- REQUIMTE/LAQV - U. Porto - Porto/Portugal, Departamento de Engenharia Metalúrgica e Materiais, Faculdade de Engenharia, Universidade do Porto, Rua, Dr. Roberto Frias, s/n, Porto, Portugal.,Faculdade de Engenharia da Universidade do Porto (FEUP), Rua Dr. Roberto Frias, Porto, Portugal
| | - A R Caseiro
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, no 228, Porto, Portugal.,Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, Portugal.,REQUIMTE/LAQV - U. Porto - Porto/Portugal, Departamento de Engenharia Metalúrgica e Materiais, Faculdade de Engenharia, Universidade do Porto, Rua, Dr. Roberto Frias, s/n, Porto, Portugal
| | - S S Pedrosa
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, no 228, Porto, Portugal.,Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, Portugal
| | - P O Pinto
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, no 228, Porto, Portugal.,Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, Portugal.,Escola Universitária Vasco da Gama (EUVG), Hospital Veterinário Universitário de Coimbra (HVUC), Campo Universitário - Bloco B, Lordemão, Coimbra, Portugal
| | - M V Branquinho
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, no 228, Porto, Portugal.,Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, Portugal
| | - I Amorim
- Department of Pathology and Molecular Immunology of the Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal.,Institute for Research and Innovation in Health, (i3S), University of Porto, Porto, Portugal.,Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Porto, Portugal
| | - J D Santos
- REQUIMTE/LAQV - U. Porto - Porto/Portugal, Departamento de Engenharia Metalúrgica e Materiais, Faculdade de Engenharia, Universidade do Porto, Rua, Dr. Roberto Frias, s/n, Porto, Portugal.,Faculdade de Engenharia da Universidade do Porto (FEUP), Rua Dr. Roberto Frias, Porto, Portugal
| | - T Pereira
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, no 228, Porto, Portugal.,Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, Portugal
| | - C M Mendonça
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, no 228, Porto, Portugal.,Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, Portugal
| | - A Afonso
- Faculdade de Medicina Dentária da Universidade do Porto (FMDUP), Porto, Portugal
| | - L M Atayde
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, no 228, Porto, Portugal.,Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, Portugal
| | - A C Maurício
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, no 228, Porto, Portugal.,Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências, Tecnologias e Agroambiente da Universidade do Porto (ICETA), Rua D. Manuel II, Apartado 55142, Porto, Portugal
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12
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Fidalgo C, Rodrigues MA, Peixoto T, Lobato JV, Santos JD, Lopes MA. Development of asymmetric resorbable membranes for guided bone and surrounding tissue regeneration. J Biomed Mater Res A 2018; 106:2141-2150. [PMID: 29603876 DOI: 10.1002/jbm.a.36420] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 03/22/2018] [Accepted: 03/27/2018] [Indexed: 12/12/2022]
Abstract
Membranes design for guided tissue engineering have been studied to aid in cell viability and function as tissue barriers. Two asymmetric resorbable membranes for guided bone regeneration (GBR) were produced: chitosan/pectin/poly-caprolactone (PECm) and poly(vinyl alcohol)/polyethylenimine/poly(ethylene glycol) (PVAm). Both membranes were characterized by physical, chemical, mechanical, degradation rate, and in vitro biological assessment. Scanning electron microscopy (SEM) confirmed the membranes asymmetry, in which PECm asymmetry is given by roughness and chemical composition, while PVAm's only by differences in porosity. Fourier transform infrared spectroscopy (FTIR) identified chemical groups and bonds between polymers. Both sides of PVAm revealed to be hydrophobic, whereas the PECm presented one side with higher hydrophobicity than the other. In vitro biological assessment disclosed that PECm presented a higher cell adhesion growth pattern than PVAm, where it seemed to occur a delay in proliferation due to initial low cell adhesion. Both developed membranes are suitable for GBR, since both membranes fulfil the requirements to be used as a tissue barrier. The PECm has an additional role in cell viability that was not observed in the PVAm. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2141-2150, 2018.
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Affiliation(s)
- C Fidalgo
- Departamento de Engenharia Metalúrgica e Materiais, Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, Porto, 4200-465, Portugal
| | - M A Rodrigues
- Departamento de Engenharia Metalúrgica e Materiais, Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, Porto, 4200-465, Portugal
| | - T Peixoto
- Departamento de Engenharia Metalúrgica e Materiais, Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, Porto, 4200-465, Portugal
| | - J V Lobato
- Centro Hospitalar Vila nova de Gaia/Espinho, Serviço de Estomatologia, Rua Conceição Fernandes, Vila Nova de Gaia, 4434-502, Portugal.,Faculdade de Ciências da Saúde - Universidade Fernando Pessoa, , Porto, Portugal
| | - J D Santos
- REQUIMTE-LAQV, Departamento de Engenharia Metalúrgica e Materiais, Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, Porto, 4200-465, Portugal
| | - M A Lopes
- REQUIMTE-LAQV, Departamento de Engenharia Metalúrgica e Materiais, Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, Porto, 4200-465, Portugal
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Zu'bi F, Sidler M, Harvey E, Lopes RI, Hojjat A, Naoum N, Pokarowski M, Lorenzo AJ, Farhat WA, Papanikolaou F, Dos Santos J. Stone growth patterns and risk for surgery among children presenting with hypercalciuria, hypocitraturia and cystinuria as underlying metabolic causes of urolithiasis. J Pediatr Urol 2017; 13:357.e1-357.e7. [PMID: 28865885 DOI: 10.1016/j.jpurol.2017.06.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Accepted: 06/29/2017] [Indexed: 10/19/2022]
Abstract
INTRODUCTION Hypercalciuria, hypocitraturia and cystinuria are the most common underlying metabolic stone abnormalities in children. The present study compared stone growth patterns, stone burden, and the risk of stone-related surgery among these underlying metabolic conditions. METHODS A retrospective cohort of 356 children with renal stones, followed from 2000 to 2015, was studied. Differences among metabolic groups were determined using Kruskal-Wallis test; the Scheffé-test was used for multiple comparisons to determine differences among single groups. Independent sample t-test was used when adequate, given the sample size, and Chi-squared test was used for categorical variables. Stone growth rates were calculated as differences in diameter divided by time elapsed between U/Ss (mm/year). Logistic regression was performed to assess the effect of initial stone size on the likelihood of surgery. RESULTS Median stone size at presentation was significantly different among groups, with cystinuria being the group with the largest proportion of stones >10 mm, while patients with stones <5 mm were likely to have a normal metabolic workup (P < 0.05). Stones with a higher growth rate were found in the operative group, while slower growing stones were mostly managed conservatively (3.4 mm/year vs 0.8 mm/year, respectively; P = 0.014). However, stone growth rates were not significantly different among metabolic groups. On the other hand, the rate of new stone formation in cystinuric patients at their first follow-up was 30.4%, which was significantly higher than in patients with hypercalciuria (16.3%) or with a normal metabolic workup (17.2%; P < 0.05). Compared with stones <5 mm, stones measuring 5-10 mm were more than four times more likely to result in surgery, whereas the likelihood of surgery for 10-20 mm or >20 mm stones was almost 16 or 34 times, respectively (P < 0.001). CONCLUSIONS It is believed that this is the first study to evaluate stone growth patterns, stone burden and surgical risk among children with hypercalciuria, hypocitraturia and cystinuria. Cystinuric patients presented with larger stones at the time of diagnosis, higher new stone formation rates, and were at higher risk of surgery. While no significant difference of growth rate was found among metabolic groups, stones with a higher growth rate were significantly more likely to result in surgical treatment than slower growing stones. Initial stone size, location of largest stone, previous urinary tract infection, and patient's metabolic type significantly influenced the likelihood of a surgical intervention. Better understanding of the natural history ultimately helps surgeons and clinicians defining prognosis, treatment, and prevention plans for pediatric urolithiasis.
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Affiliation(s)
- F Zu'bi
- Division of Urology, The Hospital for Sick Children, Toronto, ON, Canada
| | - M Sidler
- Department of Neonatal and Paediatric Surgery, Great Ormond Street Hospital, London, UK.
| | - E Harvey
- Division of Urology, The Hospital for Sick Children, Toronto, ON, Canada
| | - R I Lopes
- Division of Urology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Asal Hojjat
- Division of Urology, The Hospital for Sick Children, Toronto, ON, Canada
| | - N Naoum
- Division of Urology, The Hospital for Sick Children, Toronto, ON, Canada
| | - M Pokarowski
- Division of Urology, The Hospital for Sick Children, Toronto, ON, Canada
| | - A J Lorenzo
- Division of Urology, The Hospital for Sick Children, Toronto, ON, Canada
| | - W A Farhat
- Division of Urology, The Hospital for Sick Children, Toronto, ON, Canada
| | - F Papanikolaou
- Division of Urology, The Hospital for Sick Children, Toronto, ON, Canada
| | - J Dos Santos
- Division of Urology, The Hospital for Sick Children, Toronto, ON, Canada
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14
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Dias AG, Lopes MA, Santos JD, Afonso A, Tsuru K, Osaka A, Hayakawa S, Takashima S, Kurabayashi Y. In vivo Performance of Biodegradable Calcium Phosphate Glass Ceramics using the Rabbit Model: Histological and SEM Observation. J Biomater Appl 2016; 20:253-66. [PMID: 16364965 DOI: 10.1177/0885328206052466] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Two MK5 (45CaO-45P2O5-5MgO-5K2O, in mol%) and MT13 (45CaO-37P2O5-5MgO-13TiO2, in mol%) glasses are prepared in the meta- and pyrophosphate regions and crystallized to obtain MK5B and MT13B, respectively. MK5B was obtained by controlled crystallization, and MT13B by powder sintering. As a result of these heat treatment processes, the crystalline phases precipitated in the glassy matrix are KCa(PO3)3, β-Ca(PO3)2, β-Ca2P2O7and Ca4P6O19phases for MK5B and CaTi4(PO4)6, TiP2O7, α- and β-Ca2P2O7phases for MT13B. To assess the in vivo biological behavior of these glass ceramics, a mixed granulometry in the range 250-355 μm and 355-425 μm with a ratio of 1/1 was implanted for 2, 4, and 12 weeks in the tibiae of Japanese white rabbits. The results showed that the in vivo behavior was strongly affected by their solubility. All implanted materials, MK5B and MT13B, and β-tricalcium phosphate (β-TCP) as control material, showed signs of degradation in vivo. However, the levels of degradation were quite different throughout the implantation periods. The highest degradation was observed for MK5B glass ceramic and the lowest for MT13B with β-TCP in-between. All implanted materials allow for new bone formation in the bone defect area. At the longest implantation period (12 weeks), the MT13B and β-TCP materials were almost completely surrounded by new bone tissue, whereas MK5B showed some unfilled spaces. This behavior is discussed in terms of the high degradation observed in previous studies.
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Affiliation(s)
- A G Dias
- Instituto de Engenharia Biomédica, INEB, Laboratório de Biomateriais, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal
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15
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Funde AM, Nasibulin AG, Syed HG, Anisimov AS, Tsapenko A, Lund P, Santos JD, Torres I, Gandía JJ, Cárabe J, Rozenberg AD, Levitsky IA. Carbon nanotube-amorphous silicon hybrid solar cell with improved conversion efficiency. Nanotechnology 2016; 27:185401. [PMID: 27005494 DOI: 10.1088/0957-4484/27/18/185401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report a hybrid solar cell based on single walled carbon nanotubes (SWNTs) interfaced with amorphous silicon (a-Si). The high quality carbon nanotube network was dry transferred onto intrinsic a-Si forming Schottky junction for metallic SWNT bundles and heterojunctions for semiconducting SWNT bundles. The nanotube chemical doping and a-Si surface treatment minimized the hysteresis effect in current-voltage characteristics allowing an increase in the conversion efficiency to 1.5% under an air mass 1.5 solar spectrum simulator. We demonstrated that the thin SWNT film is able to replace a simultaneously p-doped a-Si layer and transparent conductive electrode in conventional amorphous silicon thin film photovoltaics.
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Affiliation(s)
- Adinath M Funde
- Department of Applied Physics, Aalto University, PO Box 15100, FI-00076 Aalto, Finland. School of Energy Studies, Savitribai Phule Pune University (formerly University of Pune), Ganeshkhind, Pune-411007, India
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16
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Gonçalves C, Ribeiro J, Pereira T, Luís AL, Mauricio AC, Santos JD, Lopes MA. Preparation and characterization of electrical conductive PVA based materials for peripheral nerve tube-guides. J Biomed Mater Res A 2016; 104:1981-7. [PMID: 27027727 DOI: 10.1002/jbm.a.35730] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 02/15/2016] [Accepted: 03/25/2016] [Indexed: 11/06/2022]
Abstract
Peripheral nerve regeneration is a serious clinical problem. Presently, there are several nerve tube-guides available in the market, however with some limitations. The goal of this work was the development of a biomaterial with high electrical conductivity to produce tube-guides for nerve regeneration after neurotmesis injuries whenrver an end-to-end suture without tension is not possible. A matrix of poly(vinyl alcohol) (PVA) was used loaded with the following electrical conductive materials: COOH-functionalized multiwall carbon nanotubes (MWCNTs), poly(pyrrole) (PPy), magnesium chloride (MgCl2 ), and silver nitrate (AgNO3 ). The tube-guide production was carried out by a freezing/thawing process (physical crosslinking) with a final annealing treatment. After producing the tube-guide for nerve regeneration, the physicochemical characterization was performed. The most interesting results were achieved by loading PVA with 0.05% of PPy or COOH- functionalized CNTs. These tubes combined the electrical conductivity of carbon nanotubes (CNTs) and PPy with the biocompatibility of PVA matrix, with potential clinical application for nerve regeneration. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1981-1987, 2016.
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Affiliation(s)
- C Gonçalves
- CEMUC, Departamento De Engenharia Metalúrgica E Materiais, Faculdade De Engenharia, Universidade Do Porto, (FEUP), Rua Dr. Roberto Frias, Porto, S/N 4200-465, Portugal
| | - J Ribeiro
- Departamento De Clínicas Veterinárias, Instituto De Ciências Biomédicas De Abel Salazar (ICBAS), Universidade Do Porto (up), Rua De Jorge Viterbo Ferreira, Nº 228, Porto, 4050-313, Portugal.,Centro De Estudos De Ciência Animal (CECA), Instituto De Ciências e Tecnologias Agrárias E Agro-Alimentares (ICETA), Rua D. Manuel II, Apartado 55142, Porto, 4051-401, Portugal
| | - T Pereira
- Departamento De Clínicas Veterinárias, Instituto De Ciências Biomédicas De Abel Salazar (ICBAS), Universidade Do Porto (up), Rua De Jorge Viterbo Ferreira, Nº 228, Porto, 4050-313, Portugal.,Centro De Estudos De Ciência Animal (CECA), Instituto De Ciências e Tecnologias Agrárias E Agro-Alimentares (ICETA), Rua D. Manuel II, Apartado 55142, Porto, 4051-401, Portugal
| | - A L Luís
- Departamento De Clínicas Veterinárias, Instituto De Ciências Biomédicas De Abel Salazar (ICBAS), Universidade Do Porto (up), Rua De Jorge Viterbo Ferreira, Nº 228, Porto, 4050-313, Portugal.,Centro De Estudos De Ciência Animal (CECA), Instituto De Ciências e Tecnologias Agrárias E Agro-Alimentares (ICETA), Rua D. Manuel II, Apartado 55142, Porto, 4051-401, Portugal
| | - A C Mauricio
- Departamento De Clínicas Veterinárias, Instituto De Ciências Biomédicas De Abel Salazar (ICBAS), Universidade Do Porto (up), Rua De Jorge Viterbo Ferreira, Nº 228, Porto, 4050-313, Portugal.,Centro De Estudos De Ciência Animal (CECA), Instituto De Ciências e Tecnologias Agrárias E Agro-Alimentares (ICETA), Rua D. Manuel II, Apartado 55142, Porto, 4051-401, Portugal
| | - J D Santos
- CEMUC, Departamento De Engenharia Metalúrgica E Materiais, Faculdade De Engenharia, Universidade Do Porto, (FEUP), Rua Dr. Roberto Frias, Porto, S/N 4200-465, Portugal
| | - M A Lopes
- CEMUC, Departamento De Engenharia Metalúrgica E Materiais, Faculdade De Engenharia, Universidade Do Porto, (FEUP), Rua Dr. Roberto Frias, Porto, S/N 4200-465, Portugal
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17
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Valente TAM, Silva DM, Gomes PS, Fernandes MH, Santos JD, Sencadas V. Effect of Sterilization Methods on Electrospun Poly(lactic acid) (PLA) Fiber Alignment for Biomedical Applications. ACS Appl Mater Interfaces 2016; 8:3241-3249. [PMID: 26756809 DOI: 10.1021/acsami.5b10869] [Citation(s) in RCA: 116] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Medically approved sterility methods should be a major concern when developing a polymeric scaffold, mainly when commercialization is envisaged. In the present work, poly(lactic acid) (PLA) fiber membranes were processed by electrospinning with random and aligned fiber alignment and sterilized under UV, ethylene oxide (EO), and γ-radiation, the most common ones for clinical applications. It was observed that UV light and γ-radiation do not influence fiber morphology or alignment, while electrospun samples treated with EO lead to fiber orientation loss and morphology changing from cylindrical fibers to ribbon-like structures, accompanied to an increase of polymer crystallinity up to 28%. UV light and γ-radiation sterilization methods showed to be less harmful to polymer morphology, without significant changes in polymer thermal and mechanical properties, but a slight increase of polymer wettability was detected, especially for the samples treated with UV radiation. In vitro results indicate that both UV and γ-radiation treatments of PLA membranes allow the adhesion and proliferation of MG 63 osteoblastic cells in a close interaction with the fiber meshes and with a growth pattern highly sensitive to the underlying random or aligned fiber orientation. These results are suggestive of the potential of both γ-radiation sterilized PLA membranes for clinical applications in regenerative medicine, especially those where customized membrane morphology and fiber alignment is an important issue.
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Affiliation(s)
- T A M Valente
- Departamento de Engenharia Metalúrgica e Materiais, Faculdade de Engenharia, Universidade do Porto , Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - D M Silva
- Biosckin, Molecular, and Cell Therapies, SA. Parque Tecnológico da Maia-Tecmaia , Rua Eng.° Frederico Ulrich, 2650, 4470-605 Maia, Portugal
| | - P S Gomes
- Faculdade de Medicina Dentária, Universidade do Porto , Rua Dr. Manuel Pereira da Silva, 4200-393 Porto, Portugal
| | - M H Fernandes
- Faculdade de Medicina Dentária, Universidade do Porto , Rua Dr. Manuel Pereira da Silva, 4200-393 Porto, Portugal
| | - J D Santos
- Departamento de Engenharia Metalúrgica e Materiais, Faculdade de Engenharia, Universidade do Porto , Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
- CEMUC, Departamento de Engenharia Metalúrgica e Materiais, Faculdade de Engenharia, Universidade do Porto , Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - V Sencadas
- School of Mechanical, Materials, and Mechatronics Engineering, University of Wollongong , Wollongong, NSW 2522, Australia
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18
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Morais DS, Fernandes S, Gomes PS, Fernandes MH, Sampaio P, Ferraz MP, Santos JD, Lopes MA, Sooraj Hussain N. Novel cerium doped glass-reinforced hydroxyapatite with antibacterial and osteoconductive properties for bone tissue regeneration. Biomed Mater 2015; 10:055008. [DOI: 10.1088/1748-6041/10/5/055008] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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19
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Morais DS, Coelho J, Lopes MA, Ferraz MP, Gomes P, Fernandes MH, Santos JD, Sooraj Hussain N. Microanalysis of Bioactive Samarium Doped Glass-Reinforced Hydroxyapatite. Microsc Microanal 2015; 21 Suppl 5:31-32. [PMID: 26227696 DOI: 10.1017/s1431927615013963] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Affiliation(s)
- D S Morais
- 1CEMUC,Departamento de Engenharia Metalúrgica e Materiais, Faculdade de Engenharia,Universidade do Porto (FEUP),Rua Dr. Roberto Frias,Porto,Portugal
| | - J Coelho
- 2INESC Porto,Rua do Campo Alegre,Porto,Portugal
| | - M A Lopes
- 1CEMUC,Departamento de Engenharia Metalúrgica e Materiais, Faculdade de Engenharia,Universidade do Porto (FEUP),Rua Dr. Roberto Frias,Porto,Portugal
| | - M P Ferraz
- 3CEBIMED - Centro de Estudos em Biomedicina, Faculdade de Ciências da Saúde,Universidade Fernando Pessoa (FCS-UFP),Porto,Portugal
| | - P Gomes
- 4Faculdade de Medicina Dentária,Universidade do Porto (FMDUP),Rua Dr. Manuel Pereira da Silva,Porto,Portugal
| | - M H Fernandes
- 4Faculdade de Medicina Dentária,Universidade do Porto (FMDUP),Rua Dr. Manuel Pereira da Silva,Porto,Portugal
| | - J D Santos
- 1CEMUC,Departamento de Engenharia Metalúrgica e Materiais, Faculdade de Engenharia,Universidade do Porto (FEUP),Rua Dr. Roberto Frias,Porto,Portugal
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Gadea G, Morata A, Santos JD, Dávila D, Calaza C, Salleras M, Fonseca L, Tarancón A. Towards a full integration of vertically aligned silicon nanowires in MEMS using silane as a precursor. Nanotechnology 2015; 26:195302. [PMID: 25902702 DOI: 10.1088/0957-4484/26/19/195302] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Silicon nanowires present outstanding properties for electronics, energy, and environmental monitoring applications. However, their integration into microelectromechanical systems (MEMS) is a major issue so far due to low compatibility with mainstream technology, which complicates patterning and controlled morphology. This work addresses the growth of 〈111〉 aligned silicon nanowire arrays fully integrated into standard MEMS processing by means of the chemical vapor deposition-vapor liquid solid method (CVD-VLS) using silane as a precursor. A reinterpretation of the galvanic displacement method is presented for selectively depositing gold nanoparticles of controlled size and shape. Moreover, a comprehensive analysis of the effects of synthesis temperature and pressure on the growth rate and alignment of nanowires is presented for the most common silicon precursor, i.e., silane. Compared with previously reported protocols, the redefined galvanic displacement together with a silane-based CVD-VLS growth methodology provides a more standard and low-temperature (<650 °C) synthesis scheme and a compatible route to reliably grow Si nanowires in MEMS for advanced applications.
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Affiliation(s)
- G Gadea
- Catalonia Institute for Energy Research (IREC), Jardins de les Dones de Negre 1, 08930 Sant Adrià de Besòs, Barcelona, Spain
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21
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Atayde LM, Cortez PP, Pereira T, Armada-da-Silva PAS, Afonso A, Lopes MA, Santos JD, Maurício AC. A new sheep model with automatized analysis of biomaterial-induced bone tissue regeneration. J Mater Sci Mater Med 2014; 25:1885-1901. [PMID: 24771285 DOI: 10.1007/s10856-014-5216-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Accepted: 04/06/2014] [Indexed: 06/03/2023]
Abstract
Presently, several bone graft substitutes are being developed or already available for clinical use. However, the limited number of clinical and in vivo trials for direct comparison between these products may complicate this choice. One of the main reasons for this scarcity it is the use of models that do not readily allow the direct comparison of multiple bone graft substitutes, due especially to the small number of implantation sites. Although sheep cancellous bone models are now well established for these purposes, the limited availability of cancellous bone makes it difficult to find multiple comparable sites within a same animal. These limitations can be overcome by the monocortical model here proposed as it consists in 5-6 holes (5 mm Ø), in the femoral diaphysis, with similar bone structure, overlying soft tissue and loading pattern for all defects. Associated to this model, it is also described a fast histomorphometric analysis method using a computer image segmentation test (Threshold method) to assess bone regeneration parameters. The information compiled through the experimental use of 45 sheep in several studies allowed determining that this ovine model has the potential to demonstrate differences in bone-forming performance between various scaffolds. Additionally, the described histomorphometric method is fast, accurate and reproducible.
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Affiliation(s)
- L M Atayde
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, no 228, 4050-313, Porto, Portugal,
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22
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Atayde LM, Cortez PP, Afonso A, Santos M, Maurício AC, Santos JD. Morphology effect of bioglass-reinforced hydroxyapatite (Bonelike(®) ) on osteoregeneration. J Biomed Mater Res B Appl Biomater 2014; 103:292-304. [PMID: 24819340 DOI: 10.1002/jbm.b.33195] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 04/17/2014] [Accepted: 04/28/2014] [Indexed: 11/11/2022]
Abstract
In the last decades, the well-known disadvantages of autografts and allografts have driven to the development of synthetic bone grafts for bone regeneration. Bonelike(®) , a glass-reinforced hydroxyapatite (HA) composite was developed and registered for bone grafting. This biomaterial is composed by a modified HA matrix, with α- and β-tricalcium phosphate secondary phases. Aiming to improve the biological characteristics of Bonelike(®) , new spherical pelleted granules, of different shape and size, were developed with controlled micro and macrostructure. In the present study, it was compared the physicochemical properties and in vivo performance of different Bonelike(®) granule presentations-Bonelike(®) polygonal (500-1000 µm size) and Bonelike spherical (250-500 µm; 500-1000 µm size). For the in vivo study, Bonelike(®) was implanted on sheep femurs, with various implantation times (30 days, 60 days, 120 days, and 180 days). X-ray diffraction analysis revealed that the phase composition of different granules presentations was similar. Bonelike(®) spherical 500-1000 µm was the most porous material (global porosity and intraporosity) and Bonelike(®) polygonal 500-1000 µm the less porous. Considering the in vivo study, both polygonal and spherical granules presented osteoconductive proprieties. The spherical granules showed several advantages, including easier medical application through syringe and improved osteointegration, osteoconduction, and degradation, by the presence of larger pores, controlled micro- and macrosctructure and suitable particle format that adapts to bone growth. Bonelike(®) spherical 500-1000 µm showed improved new bone invasion throughout the material's structure and Bonelike(®) spherical 250-500 µm appeared to induce faster bone regeneration, presenting less unfilled areas and less lacunae in the histological analysis.
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Affiliation(s)
- L M Atayde
- Departamento de Clínicas Veterinárias, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), Rua de Jorge Viterbo Ferreira, n° 228, 4050-313, Porto, Portugal; Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências e Tecnologias Agrárias e Agro-Alimentares (ICETA), Rua D. Manuel II, Apartado 55142, 4051-401, Porto, Portugal
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23
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Morais DS, Rodrigues MA, Lopes MA, Coelho MJ, Maurício AC, Gomes R, Amorim I, Ferraz MP, Santos JD, Botelho CM. Biological evaluation of alginate-based hydrogels, with antimicrobial features by Ce(III) incorporation, as vehicles for a bone substitute. J Mater Sci Mater Med 2013; 24:2145-2155. [PMID: 23756964 DOI: 10.1007/s10856-013-4971-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 05/31/2013] [Indexed: 06/02/2023]
Abstract
A novel hydrogel, based on an alginate/hyaluronate mixture and Ce(III) ions, with effective bioactive and antimicrobial ability was developed to be used as vehicle of a synthetic bone substitute producing an injectable substitute (IBS). Firstly, three different IBSs were prepared using three developed alginate-based hydrogels, the hydrogel Alg composed by alginate, the hydrogel Alg/Ch composed by an alginate/chitosan mixture and the hydrogel Alg/HA composed by an alginate/hyaluronate mixture. MG63 cells viability on the IBSs was evaluated, being observed a significantly higher cell viability on the Alg/HA_IBS at all time points, which indicates a better cell adaptation to the material, increasing their predisposition to produce extracellular matrix and thus allowing a better bone regeneration. Moreover, SEM analysis showed evident filopodia and a spreader shape of MG63 cells when seeded on Alg/HA_IBS. This way, based upon the in vitro results, the hydrogel Alg/HA was chosen to the in vivo study by subcutaneous implantation in an animal model, promoting a slight irritating tissue response and visible tissue repairing. The next step was to grant antimicrobial properties to the hydrogel that showed the best biological behavior by incorporation of Ce(III) ions into the Alg/HA, producing the hydrogel Alg/HA2. The antimicrobial activity of these hyaluronate-based hydrogels was evaluated against Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa and Candida albicans. Results showed that Ce(III) ions can significantly enhance the hydrogel antimicrobial ability without compromising the osteoconductivity improvement promoted by the vehicle association to the synthetic bone substitute.
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Affiliation(s)
- D S Morais
- Instituto de Biotecnologia e Bioengenharia, Centro de Engenharia Biológica, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal
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24
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Stumpf R, Dos Santos J, Gomes LB, Silva CN, Tessmann DJ, Ferreira FD, Machinski M, Del Ponte EM. Fusarium species and fumonisins associated with maize kernels produced in Rio Grande do Sul State for the 2008/09 and 2009/10 growing seasons. Braz J Microbiol 2013; 44:89-95. [PMID: 24159288 PMCID: PMC3804182 DOI: 10.1590/s1517-83822013000100012] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Accepted: 07/02/2012] [Indexed: 12/04/2022] Open
Abstract
Ear rots caused by Fusarium spp. are among the main fungal diseases that contribute to poor quality and the contamination of maize grains with mycotoxins. This study aimed to determine the visual incidence of fungal-damaged kernels (FDKs), the incidence of two main Gibberella (a teleomorph of Fusarium) complexes (G. fujikuroi and G. zeae) associated with maize using a seed health blotter test, and the fumonisin levels, using high performance liquid chromatography, in samples of maize grains grown across 23 municipalities during the 2008/09 and 2009/10 growing seasons. Additionally, 104 strains that were representative of all of the analysed samples were identified to species using PCR assays. The mean FDK was seven per cent, and only six of the samples had levels greater than six per cent. Fusarium spp. of the G. fujikuroi complex were present in 96% of the samples, and G. zeae was present in 18% of the samples (5/27). The mean incidence of G. fujikuroi was 58%, and the incidence of G. zeae varied from 2 to 6%. FB1 was found in 58.6%, FB2 in 37.9%, and both toxins in 37.9% of the samples. The FB1 and FB2 levels were below the quantification limits for 41.3% of the samples, and the mean FB1 levels (0.66 μg/g) were higher than the mean FB2 levels (0.42 μg/g). The PCR identification separated the 104 isolates into three of the G. fujikuroi complex: F. verticillioides (76%), F. subglutinans (4%) and F. proliferatum (2%); and G. zeae (anamorph = F. graminearum) (18%). Our results confirmed the dominance of F. verticillioides, similar to other regions of Brazil, but they differed due to the relatively higher incidence of F. graminearum. Total fumonisin levels were below the maximum limit determined by current Brazilian regulations.
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Affiliation(s)
- R Stumpf
- Departamento de Fitossanidade, Faculdade de Agronomia, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
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25
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Vega V, Rosa WO, García J, Sánchez T, Santos JD, Béron F, Pirota KR, Prida VM, Hernando B. Template-assisted CoPd nanowire arrays: magnetic properties and FORC analysis. J Nanosci Nanotechnol 2012; 12:4736-4743. [PMID: 22905524 DOI: 10.1166/jnn.2012.4908] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Highly hexagonally ordered CoPd alloy nanowire arrays were synthesized through electrochemical deposition techniques into the nanopores of anodic alumina membranes used as templates. Two different electrolytes were used for this purpose, one with pH = 4.1 and the other with pH = 7. Under applying different electrodeposition parameters and by adjusting both, the current density and the electrolyte composition, it could be possible make to vary the composition of CoPd alloy nanowires in a wide range. Their composition and morphology were investigated by SEM and EDX. The magnetic properties of the nanowires array have been measured with a VSM as a function of the temperature, ranging from RT down to 50 K, for different CoPd alloy nanowires composition. Also, the temperature influence on the reversible-irreversible magnetization processes related with the magnetization reversal of the CoPd nanowires array has been analyzed by first order reversal curve (FORC) method.
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Affiliation(s)
- V Vega
- Depto. de Física, Universidad de Oviedo, Calvo Sotelo s/n, 33007-0viedo, Asturias, Spain
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26
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Cortez PP, Atayde LM, Silva MA, Armada-da-Silva P, Fernandes MH, Afonso A, Lopes MA, Maurício AC, Santos JD. Characterization and preliminary in vivo evaluation of a novel modified hydroxyapatite produced by extrusion and spheronization techniques. J Biomed Mater Res B Appl Biomater 2011; 99:170-9. [PMID: 21714082 DOI: 10.1002/jbm.b.31884] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 04/21/2011] [Accepted: 04/26/2011] [Indexed: 11/07/2022]
Abstract
A glass-reinforced hydroxyapatite (HA) composite, recently registered as Bonelike®, was developed for bone grafting. This biomaterial is composed of a modified HA matrix with α- and β-tricalcium phosphate secondary phases and ionic species that mimic the chemical composition of human bone. Several in vitro and in vivo studies have confirmed the benefits of these properties. However, these studies were all executed with Bonelike® polygonal granules obtained by crushing. In this study, Bonelike® pellets were produced through a patented process, which required the use of techniques such as extrusion and spheronization. The final product presented a homogeneous size, a 55.1% global porosity and a spherical shape. This spherical shape permitted a better adaptation to the implantation site and improved injectability. Additionally, it also may contribute to formation of macropores as pellets packaging leaves open spaces. After implantation of Bonelike® polygonal granules and Bonelike® pellets in monocortical defects in sheep for 8 and 12 weeks, light microscopy and scanning electron microscopy showed extensive osteointegration simultaneously with bone regeneration for both presentations. Histomorphometric analysis did not reveal statistically significant differences between defects treated with Bonelike® polygonal granules and Bonelike® pellets, which suggests similar in vivo performances.
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Affiliation(s)
- P P Cortez
- Centro de Estudos de Ciência Animal (CECA), Instituto de Ciências e Tecnologias Agrárias e Agro-Alimentares (ICETA), Universidade do Porto, 4485-661 Vairão, Portugal.
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27
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Futata E, Azor M, Dos Santos J, Maruta C, Sotto M, Guedes F, Rivitti E, Duarte A, Sato M. Impaired IFN-α secretion by plasmacytoid dendritic cells induced by TLR9 activation in chronic idiopathic urticaria. Br J Dermatol 2011; 164:1271-9. [PMID: 21198536 DOI: 10.1111/j.1365-2133.2010.10198.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Understanding the early events of the immune response, through the activation of plasmacytoid dendritic cells (pDC) by Toll-like receptor (TLR)9-sensing, could contribute to the evaluation of immune dysregulation in chronic idiopathic urticaria (CIU). OBJECTIVES We decided to investigate innate immunity in CIU and the mechanisms implicated in the modulation of interferon (IFN)-α production by pDC upon TLR9 activation. METHODS Patients with CIU (n = 31) and healthy control subjects (HC, n = 36) were enrolled in the study. Leucocytes cultured with the TLR9 ligand, CpG type A, or with inhibitory-oligodeoxynucleotide (ODN) were used to determine IFN-α secretion by enzyme-linked immunosorbent assay. Enumeration of pDC, intracellular IFN-α and signal transducers and activators of transcription protein (STAT) (1 and 4) phosphorylation were assessed by flow cytometry. TLR9 and regulatory factor-7 mRNA transcripts were evaluated by real-time polymerase chain reaction. Evidence of pDC in the skin lesions of patients was analysed with immunohistochemistry staining. RESULTS The findings show a decreased IFN-α secretion induced by CpG A by leucocytes, due to the diminished IFN-α expression on pDC in CIU. It was mediated by TLR9-activation since inhibitory-ODN further suppressed TLR9-induced IFN-α secretion. A normal pDC percentage and degree of activation by the expression of costimulatory molecules was observed in CIU, with the rare presence of pDC in the skin lesion. In addition, an increased constitutive STAT1 phosphorylation on nonstimulated lymphocytes and a downregulation of TLR9 mRNA transcripts after CpG A activation were verified in patients with CIU. CONCLUSIONS The findings showed an innate immune response in CIU disturbed by impairment of the pDC response to TLR9 activation.
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Affiliation(s)
- E Futata
- University of São Paulo, Department of Dermatology, São Paulo, Brazil
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28
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Simões MJ, Gärtner A, Shirosaki Y, Gil da Costa RM, Cortez PP, Gartnër F, Santos JD, Lopes MA, Geuna S, Varejão ASP, Maurício AC. In vitro and in vivo chitosan membranes testing for peripheral nerve reconstruction. ACTA MEDICA PORT 2011. [DOI: 10.20344/amp.344] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Tissue regeneration over a large defect with a subsequent satisfactory functional recovery still stands as a major problem in areas such as nerve regeneration or bone healing. The routine technique for the reconstruction of a nerve gap is the use of autologous nerve grafting, but still with severe complications. Over the last decades several attempts have been made to overcome this problem by using biomaterials as scaffolds for guided tissue regeneration. Despite the wide range of biomaterials available, functional recovery after a serious nerve injury is still far from acceptable. Prior to the use of a new biomaterial on healing tissues, an evaluation of the host's inflammatory response is mandatory. In this study, three chitosan membranes were tested in vitro and in vivo for later use as nerve guides for the reconstruction of peripheral nerves submitted to axonotmesis or neurotmesis lesions. Chitosan membranes, with different compositions, were tested in vitro, with a nerve growth factor cellular producing system, N1E-115 cell line, cultured over each of the three membranes and differentiated for 48h in the presence of 1.5% of DMSO. The intracellular calcium concentrations of the non-differentiated and of the 48h-differentiated cells cultured on the three types of the chitosan membranes were measured to determine the cell culture viability. In vivo, the chitosan membranes were implanted subcutaneously in a rat model, and histological evaluations were performed from material retrieved on weeks 1, 2, 4 and 8 after implantation. The three types of chitosan membranes were a viable substrate for the N1E-115 cell multiplication, survival and differentiation. Furthermore, the in vivo studies suggested that these chitosan membranes are promising candidates as a supporting material for tissue engineering applications on the peripheral nerve, possibly owing to their porous structure, their chemical modifications and high affinity to cellular systems.
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29
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Simões MJ, Gärtner A, Shirosaki Y, Gil da Costa RM, Cortez PP, Gartnër F, Santos JD, Lopes MA, Geuna S, Varejão ASP, Maurício AC. In vitro and in vivo chitosan membranes testing for peripheral nerve reconstruction. ACTA MEDICA PORT 2011; 24:43-52. [PMID: 21672441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2009] [Accepted: 09/25/2009] [Indexed: 05/30/2023]
Abstract
Tissue regeneration over a large defect with a subsequent satisfactory functional recovery still stands as a major problem in areas such as nerve regeneration or bone healing. The routine technique for the reconstruction of a nerve gap is the use of autologous nerve grafting, but still with severe complications. Over the last decades several attempts have been made to overcome this problem by using biomaterials as scaffolds for guided tissue regeneration. Despite the wide range of biomaterials available, functional recovery after a serious nerve injury is still far from acceptable. Prior to the use of a new biomaterial on healing tissues, an evaluation of the host's inflammatory response is mandatory. In this study, three chitosan membranes were tested in vitro and in vivo for later use as nerve guides for the reconstruction of peripheral nerves submitted to axonotmesis or neurotmesis lesions. Chitosan membranes, with different compositions, were tested in vitro, with a nerve growth factor cellular producing system, N1E-115 cell line, cultured over each of the three membranes and differentiated for 48h in the presence of 1.5% of DMSO. The intracellular calcium concentrations of the non-differentiated and of the 48h-differentiated cells cultured on the three types of the chitosan membranes were measured to determine the cell culture viability. In vivo, the chitosan membranes were implanted subcutaneously in a rat model, and histological evaluations were performed from material retrieved on weeks 1, 2, 4 and 8 after implantation. The three types of chitosan membranes were a viable substrate for the N1E-115 cell multiplication, survival and differentiation. Furthermore, the in vivo studies suggested that these chitosan membranes are promising candidates as a supporting material for tissue engineering applications on the peripheral nerve, possibly owing to their porous structure, their chemical modifications and high affinity to cellular systems.
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Affiliation(s)
- M J Simões
- Centro de Estudos de Ciência Animal, Instituto de Ciências e Tecnologias Agrárias e Agro-Alimentares, Universidade do Porto, Portugal
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30
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Silva MA, Gomes PS, Vila M, Lopes MA, Santos JD, Silva RF, Fernandes MH. New titanium and titanium/hydroxyapatite coatings on ultra-high-molecular-weight polyethylene—
in vitro
osteoblastic performance. Biomed Mater 2010; 5:35014. [DOI: 10.1088/1748-6041/5/3/035014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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31
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Sooraj Hussain N, Hungerford G, El-Mallawany R, Gomes MJM, Lopes MA, Ali N, Santos JD, Buddhudu S. Absorption and emission analysis of RE3+(Sm3+ and Dy3+): lithium boro tellurite glasses. J Nanosci Nanotechnol 2009; 9:3672-3677. [PMID: 19504901 DOI: 10.1166/jnn.2009.ns49] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
This paper reports on the development and spectral analysis of Sm3+ (1.0%) and Dy3+ (1.0%) doped lithium-boro-tellurite glasses. A bright orange (4G5/2-->6H7/2) along with a red (4G5/2-->6H9/2) and a yellow (4G5/2-->6H5/2) emission transition have been measured from Sm3+ doped lithium-boro-tellurite glass. Both blue (4F9/2-->6H15/2) and yellow (4F9/2-->6H13/2) emission bands have been obtained from Dy3+ glass. From the measured decay profiles, the lifetimes of the emissions of the Sm3+ glass (4G5/2-->6H5/2, 7/2, 9/2 and 11/2) at an excitation of 401 nm have been found to be in the range 0.47-0.81 ms, and with respect to the Dy3+ emissions (4F9/2-->6H15/2 and 13/2), with excitation at 450 nm, are measured to be in the range of 0.302-0.307 ms. Stimulated emission cross-sections (sigmapE) of the measured emission transitions have also been computed and the values are in the range of (0.38-1.20) x 10(-20) cm2 for Sm3+ and for Dy3+ doped lithium-boro-tellurite glass the values are (0.66-1.39) x 10(-20) cm2.
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Affiliation(s)
- N Sooraj Hussain
- FEUP-Faculdade de Engenharia da Universidade do Porto, DEMM, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
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Sooraj Hussain N, Cardoso PJ, Hungerford G, Gomes MJM, Ali N, Santos JD, Buddhudu S. Physical and optical characterization of Er3+ doped lead-zinc-borate glass. J Nanosci Nanotechnol 2009; 9:3555-3561. [PMID: 19504881 DOI: 10.1166/jnn.2009.ns29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
This paper reports on the systematic optical characterization of Er3+ (1.0%) doped lead-zinc-borate glass from the measured absorption, luminescence and fluorescence lifetime decay curve profiles. By the application of the Judd-Ofelt theory, spectral intensities of the absorption bands have been analysed and these absorption results have been used in evaluating the luminescence properties of the Er3+ doped lead-zinc-borate glass. Stimulated emission cross-sections (sigmapE) of the measured emission transitions have been computed. Based on the measured glass density, and refractive indices, other related physical parameters have also been evaluated. Further, the structural and morphology of the glass material have also been investigated from X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy analysis.
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Affiliation(s)
- N Sooraj Hussain
- FEUP-Faculdade de Engenharia da Universidade do Porto, DEMM, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
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Dos Santos J, Sposito A, Faria-Neto J, Fonseca F, Ramires J, Coelho O, Bertolami M, Santos R, Tutihashi E, Cesena F. Abstract: P1259 FACTORS ASSOCIATED WITH NONADHERENCE TO LIPIDLOWERING TREATMENT AND IDENTIFICATION OF BEHAVIORAL PROFILES AMONG HYPERCHOLESTEROLEMIC INDIVIDUALS IN BRAZIL: THE CORE PROJECT. ATHEROSCLEROSIS SUPP 2009. [DOI: 10.1016/s1567-5688(09)71276-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Silva Marques JM, Gomes PS, Silva MA, Silvério Cabrita AM, Santos JD, Fernandes MH. Growth and phenotypic expression of human endothelial cells cultured on a glass-reinforced hydroxyapatite. J Mater Sci Mater Med 2009; 20:725-731. [PMID: 18987948 DOI: 10.1007/s10856-008-3628-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2008] [Accepted: 10/16/2008] [Indexed: 05/27/2023]
Abstract
Glass-reinforced hydroxyapatite composites (GR-HA) are bone regenerative materials that are characterized by their increased mechanical properties, when compared to synthetic hydroxyapatite. Bonelike is a GR-HA that is a result of the addition of a CaO-P(2)O(5) based glass to a HA matrix. This biomaterial has been successfully applied in clinical bone regenerative applications. This work aims to evaluate the ability of Bonelike to support the adhesion, proliferation and phenotypic expression of human endothelial cells, aiming to establish new bone tissue engineering pre-endothelialization strategies. Bonelike discs, regardless of being submitted to a pre-immersion treatment with culture medium, were seeded with first passage human umbilical vein endothelial cells, and characterized regarding proliferation and differentiation events. Pre-immersed Bonelike allowed the adhesion, proliferation and phenotype expression of endothelial cells. Seeded materials presented positive immunofluorescent staining for PECAM-1 and a tendency for the formation of cord-like arrangements under angiogenesis-stimulating conditions, although, compared to standard culture plates, a slight decreased cell growth was observed. In this way, Bonelike may be a suitable candidate for pre-endothelialization approaches in bone tissue engineering applications.
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Affiliation(s)
- J M Silva Marques
- Cooperativa de Ensino Superior Egas Moniz, Monte de Caparica, Portugal
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Amaral M, Gomes PS, Lopes MA, Santos JD, Silva RF, Fernandes MH. Cytotoxicity evaluation of nanocrystalline diamond coatings by fibroblast cell cultures. Acta Biomater 2009; 5:755-63. [PMID: 18819854 DOI: 10.1016/j.actbio.2008.08.015] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2008] [Revised: 07/01/2008] [Accepted: 08/26/2008] [Indexed: 12/01/2022]
Abstract
The cytotoxicity profile of nanocrystalline diamond (NCD) coatings on a Si(3)N(4) ceramic was investigated. This material is envisaged to have biomedical dental applications such as burrs and surgical instruments. Two fibroblast cell culture systems were used to address the cytotoxicity of NCD-coated samples: L929 cells (a mouse permanent cell line) and human gingival fibroblasts. Cell behavior was evaluated in terms of cell adhesion, cell viability/proliferation (mitochondrial function, MTT assay) and the pattern of cell growth. Fibroblast cell behavior on standard polystyrene culture plates was used as control, as Si(3)N(4) substrates have previously been shown to be biocompatible. NCD coatings provided a suitable surface for cell attachment, spreading and proliferation. Human gingival cells showed a homogeneous cytoplasm spreading, a flattened elongated morphology and a typical parallel alignment on confluent cultures. In comparison, L929 cells denoted a lower cytoplasm expansion, a heterogeneous spreading but a higher proliferation rate. For both cells, after few days, the NCD coating was completely covered with continuous cell layers. As compared to standard polystyrene culture plates, no deleterious or cytotoxic responses were observed with L929 and human fibroblast cell cultures, and in both a slight enhancement in cell proliferation was observed. In addition, the seeded NCD film allowed reproduction of the typical features of the two cell culture systems tested, further suggesting the lack of cytotoxicity of this coating.
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Affiliation(s)
- M Amaral
- CICECO, Department of Ceramics and Glass Engineering, University of Aveiro, 3810-193 Aveiro, Portugal.
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Amado S, Simões MJ, Armada da Silva PAS, Luís AL, Shirosaki Y, Lopes MA, Santos JD, Fregnan F, Gambarotta G, Raimondo S, Fornaro M, Veloso AP, Varejão ASP, Maurício AC, Geuna S. Use of hybrid chitosan membranes and N1E-115 cells for promoting nerve regeneration in an axonotmesis rat model. Biomaterials 2008; 29:4409-19. [PMID: 18723219 DOI: 10.1016/j.biomaterials.2008.07.043] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2008] [Accepted: 07/31/2008] [Indexed: 12/22/2022]
Abstract
Many studies have been dedicated to the development of scaffolds for improving post-traumatic nerve regeneration. The goal of this study was to develop and test hybrid chitosan membranes to use in peripheral nerve reconstruction, either alone or enriched with N1E-115 neural cells. Hybrid chitosan membranes were tested in vitro, to assess their ability in supporting N1E-115 cell survival and differentiation, and in vivo to assess biocompatibility as well as to evaluate their effects on nerve fiber regeneration and functional recovery after a standardized rat sciatic nerve crush injury. Functional recovery was evaluated using the sciatic functional index (SFI), the static sciatic index (SSI), the extensor postural thrust (EPT), the withdrawal reflex latency (WRL) and ankle kinematics. Nerve fiber regeneration was assessed by quantitative stereological analysis and electron microscopy. All chitosan membranes showed good biocompatibility and proved to be a suitable substrate for plating the N1E-115 cellular system. By contrast, in vivo nerve regeneration assessment after crush injury showed that the freeze-dried chitosan type III, without N1E-115 cell addition, was the only type of membrane that significantly improved posttraumatic axonal regrowth and functional recovery. It can be thus suggested that local enwrapping with this type of chitosan membrane may represent an effective approach for the improvement of the clinical outcome in patients receiving peripheral nerve surgery.
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Affiliation(s)
- S Amado
- Faculty of Human Kinetics (FMH), Technical University of Lisbon (UTL), Lisbon, Portugal
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Hernando B, Prida VM, Sanchez ML, Olivera J, Garcia C, Santos JD, Alvarez P, Sánchez JLL, Perov N. Thermal annealing dependence of high-frequency magnetoimpedance in amorphous and nanocrystalline FeSiBCuNb ribbons. J Nanosci Nanotechnol 2008; 8:2873-2882. [PMID: 18681021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The magnetoimpedance (MI) effect in Fe73.5Si13.5B9Nb3Cu1 melt-spun amorphous ribbons has been studied in the frequency range (1-500 MHz). Isothermal heating treatments in a furnace have been employed to nanocrystallize the ribbons (1 h at 565 degrees C in a vacuum of 10(-3) mbar), while other samples were annealed at lower temperatures (400 and 475 degrees C during 1 h), in order to evaluate the influence of the annealing temperature on the MI effect. The high-frequency impedance was measured using a technique based on the reflection coefficient measurements of a specific transmission line by using a network analyzer. Frequency dependence of the MI ratio, DeltaZ/Z, and both resistive, DeltaR/R, and reactive, DeltaX/X, components of magnetoimpedance were measured in the amorphous and annealed states, at different temperatures. A maximum value of the MI ratio of about 50% at a driving frequency of 18 MHz is obtained in the nanocrystalline (annealed at 565 degrees C) ribbon. Maxima for DeltaR/R of about 81% at 85 MHz and DeltaX/X around 140% at 5 MHz were also achieved. It is revealed that the microstructural evolution in the nanocrystalline sample leads to a magnetic softening, an optimum domain structure and a permeability which is sensitive to frequency and applied magnetic field, generating a large MI response.
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Affiliation(s)
- B Hernando
- Departamento de Física, Universidad de Oviedo, Calvo Sotelo s/n, 33007 Oviedo, Spain
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38
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Gutierres M, Lopes MA, Sooraj Hussain N, Lemos AF, Ferreira JMF, Afonso A, Cabral AT, Almeida L, Santos JD. Bone ingrowth in macroporous Bonelike for orthopaedic applications. Acta Biomater 2008; 4:370-7. [PMID: 17716960 DOI: 10.1016/j.actbio.2007.06.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2006] [Revised: 04/30/2007] [Accepted: 06/21/2007] [Indexed: 10/23/2022]
Abstract
The aim of this study was to evaluate the biological behaviour of porous scaffold structures of Bonelike which is suitable for either direct clinical use or tissue engineering applications. Porous cylindrical specimens 8x10mm were implanted in the lateral aspect of the tibia of 13 patients (mean age 54 years), during osteotomy surgery for the treatment of medial compartment osteoarthritis of the knee. Implanted cylinders were retrieved at the same time as the removal of the blade plates at 3, 6, 9 and 12 months. Scanning electron microscopy and histological evaluations were performed to observe the biological responses of human bone tissue to porous Bonelike. The penetration depth was determined for all implantation periods, and after 6 months it was already possible to see new bone in the centre of the implanted cylinders, which gives 100% of penetration depth for all implantations periods except for 3 months when bone could only be seen in the peripherical region. Regarding the percentage of the area covered by new bone calculated from two-dimensional histological sections, values of 53+/-15, 76+/-12 and 88+/-9% were achieved for 6, 9 and 12 months, respectively. Due to its structural features porous Bonelike permitted effective vascularization and bone ingrowth, and therefore was fully osteointegrated as shown in the histological surveys. A slow biomaterial degradation with implantation time is envisaged since the material has displayed surface degradation. Bonelike scaffolds show potential for complete ingrowth of osseous tissue and restoration of vascularization throughout the defected site.
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Affiliation(s)
- M Gutierres
- FMUP - Faculdade de Medicina da Universidade do Porto, Hospital de São João, Largo Hernâni Monteiro, 4200 Porto, Portugal
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Gutierres M, Dias AG, Lopes MA, Hussain NS, Cabral AT, Almeida L, Santos JD. Opening wedge high tibial osteotomy using 3D biomodelling Bonelike macroporous structures: case report. J Mater Sci Mater Med 2007; 18:2377-82. [PMID: 17569003 DOI: 10.1007/s10856-007-3171-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2006] [Accepted: 09/12/2006] [Indexed: 05/15/2023]
Abstract
Two synthetic calcium phosphates in porous wedge shape, Bonelike and a commercial HA/beta-TCP biphasic material, were used as an alternative to bone autografts and allografts in the treatment of medial compartment osteoarthritis of varus knees. The structure of Bonelike has a 3D architecture that is computer controlled, and a composition that mimics the mineral composition of natural bone. The HA/beta-TCP biphasic material used as a control material in this study was prepared using conventional foaming based methods. No signs of inflammatory reactions were observed post-operatively for both materials. After 4 months signs of fusion at the osteotomy site and good integration of the implanted wedges were observed, showing good mechanical resistance. Concerning the final correction attained, the left knee revealed a satisfactory valgus of 10 degrees , but the right one only had a final value of 6 degrees . The clinical evaluation using International Knee Score (IKS) showed good outcome in all parameters with complete range of motion in both knees and climbing stairs without crutches with only slight pain.
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Affiliation(s)
- M Gutierres
- FMUP - Faculdade de Medicina da Universidade do Porto, Hospital de São João, Largo Hernâni Monteiro, Porto 4200, Portugal
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Sousa RC, Lobato JV, Maurício AC, Hussain NS, Botelho CM, Lopes MA, Santos JD. A clinical report of bone regeneration in maxillofacial surgery using bonelike synthetic bone graft. J Biomater Appl 2007; 22:373-85. [PMID: 17494960 DOI: 10.1177/0885328207078260] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The objective of this study is to evaluate the osteoconductivity and bioactivity of the Bonelike graft in repairing surgical cystic bone defects. Bonelike is implanted in 11 patients, aged between 24 and 53 years with a mean age of 36 years, consisting of 5 men and 6 women. According to the standard follow up protocols, radiological examinations are performed and Bonelike/bone retrieved samples have been analyzed histologically using non-decalcified sections obtained perpendicular to bone length axis. Radiographic examination and histological results clearly demonstrate an extensive new bone formation apposed on Bonelike granules with a significant degree of maturation. These clinical applications in maxillary bone defects indicate perfect bone bonding between new bone formed and Bonelike granules, along with partial surface biodegradation. This quick and effective osteoconductive response from Bonelike may reduce the time needed to reconstruct the bone defected area of patients.
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Affiliation(s)
- R C Sousa
- Serviço de Estomatologia e Cirurgia Maxilofacial, Hospital Geral de Santo António, Largo Abel Salazar, 4050, Porto, Portugal
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41
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Dias AG, Gibson IR, Santos JD, Lopes MA. Physicochemical degradation studies of calcium phosphate glass ceramic in the CaO-P2O5-MgO-TiO2 system. Acta Biomater 2007; 3:263-9. [PMID: 17150421 DOI: 10.1016/j.actbio.2006.09.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2006] [Revised: 09/08/2006] [Accepted: 09/25/2006] [Indexed: 10/23/2022]
Abstract
The aim of this work was to evaluate the in vitro degradation behaviour of a 45CaO-37P(2)O(5)-5MgO-13TiO(2) (mol.%) glass ceramic, under two different simulated physiological conditions: normal physiological pH 7.4, and pH 3.0, which was designed to simulate the acidic conditions produced by osteoclast cells. The in vitro testing was carried out at 37 degrees C for up to 42 days for the pH 7.4 solution and for up to 1 day for the pH 3.0 solution. The incorporation of TiO(2) into the glass structure leads to the precipitation of specific crystalline phases in the glass matrix, namely alpha- and beta-Ca(2)P(2)O(7), TiP(2)O(7) and CaTi(4)(PO(4))(6). The degradation testing at pH 3.0 showed a higher weight loss compared with degradation testing at pH 7.4; the weight loss under the acidic condition after 1 day (24 h) was about 10 times higher than the weight loss after 42 days of immersion at pH 7.4. The ionic release profile of Ca(2+), PO(4)(3-), Mg(2+) and Ti(4+) showed a continuous increase in concentration over all immersion times for both testing solutions. After 1 day of immersion at pH 3.0, the concentration levels of Mg(2+), Ca(2+), PO(4)(3-) were about six times higher than the levels achieved after 42 days of immersion at pH 7.4. The glass ceramic showed similar degradation to hydroxyapatite, and therefore has potential to be used in certain clinical applications where relatively slow resorption of the implant and replacement by bone is required, e.g. cranioplasty.
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Affiliation(s)
- A G Dias
- Instituto de Engenharia Biomédica (INEB), Laboratório de Biomateriais, Rua do Campo Alegre 823, 4150-180 Porto, Portugal
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Lobato JV, Rodrigues JM, Cavaleiro MV, Lobato JM, Xavier L, Santos JD, Maurício AC. Maxilla osseus sequestre and oral exposure: effects of the treatment of multiple myeloma with bisphosphonates. ACTA MEDICA PORT 2007; 20:185-92. [PMID: 17868526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Multiple myeloma, the second most common haematopoietic cancer, represents a collection of plasma-cell neoplasms that invariably become fatal when self-renewing myeloma cells begin unrestrained proliferation. The major clinical manifestation of multiple myeloma is related to loss of bone through osteolysis. The bone disease can lead to pathologic fractures, spinal cord compression, hypercalcemia, and pain. It is also a major cause of morbidity and mortality in these patients. These patients frequently require radiation therapy, surgery and analgesic medications. Bisphosphonates are specific inhibitors of osteoclastic activity, and are currently used to prevent bone complications and to treat malignant hypercalcemia in patients with multiple myeloma, or bone metastases from breast and prostate cancers. Recent published reports have documented a possible link between treatment with intravenous bisphosphonates and osteonecrosis of the jaw. Bisphosphonates have been demonstrated to alter the normal bone microenvironment and appear to have direct effects on tumours as well. These changes may contribute to the development of osteonecrosis of the jaw in these patients, particularly after tooth extractions or other invasive dental procedures. Osteonecrosis of the mandible has been reported in 3 patients from Centro Hospitalar de Vila Nova de Gaia (CHVNG) with multiple myeloma treated for over 18 to 48 months with intravenous bisphosphonate zoledronate. It has been postulated that bisphosphonates may cause oral avascular bone necrosis due to antiangiogenic effect leading to disruption of osteoclast-mediated bone resorption. Although this report serves to alert clinicians about the potential complication of bone necrosis in patients receiving bisphosphonates therapy, many questions remain concerning the underlying pathogenesis of this process. In these 3 described clinical cases, surgical debridment without flap elevation, intensive antibiotherapy and zolendronate treatment arrest made possible the partial recovery of the patients. We purpose this type of clinical approach in patients suffering from multiple myeloma and bone osteonecrosis induced by bisphosphonate treatment. Research to determine the mechanism of this dental phenomenon is needed to fully validate and substantiated the possible link between bisphosphonates treatment of multiple myeloma or other cancer diseases with avascular osteonecrosis of the jaws. Until then, clinicians involved in the care of patients at risk should consider this possible complication.
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Affiliation(s)
- J V Lobato
- Centro Hospitalar de Vila Nova de Gaia, Vila Nova de Gaia
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43
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Luís AL, Amado S, Geuna S, Rodrigues JM, Simões MJ, Santos JD, Fregnan F, Raimondo S, Veloso AP, Ferreira AJA, Armada-da-Silva PAS, Varejão ASP, Maurício AC. Long-term functional and morphological assessment of a standardized rat sciatic nerve crush injury with a non-serrated clamp. J Neurosci Methods 2007; 163:92-104. [PMID: 17397932 DOI: 10.1016/j.jneumeth.2007.02.017] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2006] [Revised: 02/16/2007] [Accepted: 02/17/2007] [Indexed: 12/21/2022]
Abstract
We have recently described the sequence of functional and morphologic changes occurring after a standardized sciatic nerve crush injury. An 8-week post-injury time was used because this end point is the far most used. Unexpectedly, both functional and morphological data revealed that animals had still not recovered to normal pre-injury levels. Therefore, the present study was designed in order to prolong the observation up to 12 weeks. Functional recovery was evaluated using sciatic functional index (SFI), static sciatic index (SSI), extensor postural thrust (EPT), withdrawal reflex latency (WRL) and ankle kinematics. In addition, quantitative morphology was carried out on regenerated nerve fibers. A full functional recovery was predicted by SFI/SSI, EPT and WRL but not all ankle kinematics parameters. Moreover, only two morphological parameters (myelin thickness/axon diameter ratio and fiber/axon diameter ratio) returned to normal values. Data presented in this paper provide a baseline for selecting the adequate end-point and methods of recovery assessment for a rat sciatic nerve crush study and suggest that the combined use of functional and morphological analysis should be recommended in this experimental model.
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Affiliation(s)
- A L Luís
- Animal Science and Study Centre (CECA)/Food and Agrarian Sciences and Technologies Institute (ICETA), Porto University, Portugal
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Botelho CM, Brooks RA, Best SM, Lopes MA, Santos JD, Rushton N, Bonfield W. Human osteoblast response to silicon-substituted hydroxyapatite. J Biomed Mater Res A 2007; 79:723-30. [PMID: 16871624 DOI: 10.1002/jbm.a.30806] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Human osteoblasts were cultured on hydroxyapatite (HA), 0.8 wt % silicon substituted hydroxyapatite (Si-HA) and 1.5 wt % Si-HA discs. The influence of these substrates on cell behaviour in vitro was assessed by measuring total protein in the cell lysate and the production of several phenotypic markers: collagen type I (COL I), alkaline phosphatase (ALP), osteocalcin (OC), and the formation of bone mineral. After 7 days, beta-glycerophosphate and physiological levels of hydrocortisone were added to the culture medium to stimulate cell differentiation and mineral production. There was a significantly higher production of ALP on 1.5 wt % Si-HA at day 7 following which, the addition of hydrocortisone promoted the differentiation of cells on the other two substrates. Hydrocortisone addition also decreased the production of OC. During the period, when hydrocortisone was present, no significant difference in behavior was seen between cells on Si-HA and HA; however, following removal of hydrocortisone, cells responded to 0.8 wt % Si-HA with a significant increase in protein production. Using fluorescence microscopy, nodular structures labeled with tetracycline were observed on the surface of all substrates after 21 days. These structures were deposited on areas of high cell density but were not related to the presence or level of silicon in the substrate. These results indicate that human osteoblasts are affected by the presence of silicon in the HA substrate and that the timing of these effects may be dependent upon the level of silicon substitution.
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Affiliation(s)
- C M Botelho
- INEB- Instituto de Engenharia Biomédica, Laboratório de Biomateriais, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal
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Botelho CM, Brooks RA, Spence G, McFarlane I, Lopes MA, Best SM, Santos JD, Rushton N, Bonfield W. Differentiation of mononuclear precursors into osteoclasts on the surface of Si-substituted hydroxyapatite. J Biomed Mater Res A 2006; 78:709-20. [PMID: 16739170 DOI: 10.1002/jbm.a.30726] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In healthy bone, resorption and synthesis are in perfect coordination. In previous studies we demonstrated that the incorporation of silicon into the hydroxyapatite (HA) lattice enhances the proliferation and differentiation of human osteoblasts. Therefore, the aim of this study was to demonstrate the effect of silicon-substituted HA (0.8 and 1.5 wt % Si-HA) on the differentiation of mononuclear cells into osteoclasts, using two different starting cultures, peripheral blood mononuclear cells (PBMC) and monocytes expressing the CD14 antigen (CD14+). Through this study, it was possible to demonstrate that Si-HA allows the differentiation of mononuclear cells into mature osteoclasts, independent of the starting culture, PBMC or CD14+. Most of the cells on the surface of the materials expressed osteoclastic markers: actin rings, several nuclei, positivity for tartrate-resistant acid phosphatase (TRAP), and vitronectin receptor. In the presence of osteoclasts, a higher release of calcium and phosphate into the medium from the 1.5 wt % Si-HA substrate was detected when compared to the HA substrate; therefore, these results indicate higher osteoclastic resorptive activity on the 1.5 wt % Si-HA surface. Si-HA can be resorbed by cellular mechanisms and have a stimulatory effect on osteoclasts, although the underlying mechanism is still poorly understood.
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Affiliation(s)
- C M Botelho
- INEB-Instituto de Engenharia Biomédica, Laboratório de Biomateriais, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal
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46
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Lobato JV, Maurício AC, Rodrigues JM, Cavaleiro MV, Cortez PP, Xavier L, Botelho C, Hussain NS, Santos JD. Jaw avascular osteonecrosis after treatment of multiple myeloma with zoledronate. J Plast Reconstr Aesthet Surg 2006; 61:99-106. [PMID: 18068658 DOI: 10.1016/j.bjps.2006.06.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2006] [Accepted: 06/07/2006] [Indexed: 10/24/2022]
Abstract
PURPOSE Multiple myeloma, the second most common haematopoietic cancer, which represents the collection of plasma-cell neoplasms that invariably becomes fatal when self-renewing myeloma cells begin unrestrained proliferation. The major clinical manifestation of multiple myeloma is related to the loss of bone through osteolysis. This can lead to pathologic fractures, spinal cord compression, hypercalcaemia, and pain. It is also a major cause of morbidity and mortality in these patients, who frequently require radiation therapy, surgery and analgesic medications. Bisphosphonates are specific inhibitors of osteoclastic activity, and are currently used to prevent bone complications and to treat malignant hypercalcaemia in patients with multiple myeloma, or bone metastases from breast and prostate cancers. Hence, osteonecrosis of the mandible has been reported in three patients from Centro Hospitalar de Vila Nova de Gaia (CHVNG) with multiple myeloma treated for over 18-48 months with intravenous zoledronate, commonly prescribed for multiple myeloma therapy. Although, this report alerts clinicians about the potential complication of bone necrosis in patients receiving bisphosphonate therapy, many questions remain concerning the underlying pathogenesis of this process. PATIENTS AND METHODS The medical and dental records of three patients with multiple myeloma, who were treated in CHVNG in the past 4 years, were reviewed. These three patients presented exposed bone and osteonecrosis of the mandible, and shared one common clinical feature: all of them were treated with bisphosphonate zoledronate, administered intravenously for long periods. Sequential orthopantomograms (OPGs) and histological evaluation have been analysed from the biopsies of the non healing dental extraction sites of these patients. RESULTS After a routine dental extraction, these patients developed avascular osteonecrosis of the mandible and secondary bone infection with Actinomyces israelii (actinomycotic osteomyelitis), with no evidence of metastatic disease evaluated by biopsy. In these three described clinical cases, surgical debridment without flap elevation, intensive antibiotherapy and the suspension of the zoledronate treatment allowed a partial recovery of the patients. The purpose of this clinical report is to point out that patients suffering from multiple myeloma can develop bone osteonecrosis induced by treatment with bisphosphonates. Research to determine the mechanism of this dental phenomenon is needed to fully validate and substantiate the possible link between bisphosphonate treatment of multiple myeloma or other cancer diseases and avascular osteonecrosis of the jaws. Until then, clinicians involved in the care of patients at risk should consider this possible complication.
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Affiliation(s)
- J V Lobato
- Serviço de Estomatologia, Centro Hospitalar de Vila Nova de Gaia, Rua Conceição Fernandes, 4434-502 Vila Nova de Gaia, Portugal
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47
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Gutierres M, Hussain NS, Lopes MA, Afonso A, Cabral AT, Almeida L, Santos JD. Histological and scanning electron microscopy analyses of bone/implant interface using the novel Bonelike synthetic bone graft. J Orthop Res 2006; 24:953-8. [PMID: 16609968 DOI: 10.1002/jor.20117] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Synthetic bone grafts provide an alternative to autografts and allografts. Bonelike is a patented synthetic bone graft that mimics the mineral composition of bone. The aim of the present work was to assess the biological behavior of Bonelike graft in humans, before using the material in orthopedic applications of bone regeneration, for example, in opening wedge high tibial osteotomies for medial knee osteoarthritis. Bonelike granules were implanted in cortical bone of 11 patients undergoing osteotomies, and new bone formation, osteoconductive properties, and resorption characteristics of the granules were analyzed. The granules ranged from 500 to 1000 microm and were implanted in the lateral aspect of the tibia. The patients' mean age was 59 years (range 48 to 70 years); there were eight women and three men, all suffering from medial compartment osteoarthritis of the knee. At surgery, a 1 x 1 x 1-cm cortical defect was created 3 cm distal to the entry point of the screws, in line with the long axis of tibia. The implanted Bonelike graft sample was extracted for analysis during removal of the metallic prosthesis after implantation times of 6, 9, and 12 months. Radiological follow-up, scanning electron microscopy, histological analysis, and histomorphometric measurements were conducted on the retrieved samples to assess bone regeneration in the defect area. Osteoconductive capacity was demonstrated by extensive mature bone formation around the implanted granules and high levels of percentage bone-to-graft contact (from 67-84%). Bonelike acted as an excellent bioactive scaffold, allowing the migration, proliferation, and differentiation of bone cells on its surface, and therefore regeneration of the defects was achieved in a rapid, controlled manner. Our results suggest that Bonelike graft is an excellent candidate for orthopedic applications where rapid new bone formation is a fundamental requirement.
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Affiliation(s)
- M Gutierres
- FMUP-Faculdade de Medicina da Universidade do Porto, Hospital de São João, Largo Hernâni Monteiro, 4200 Porto, Portugal
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48
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Rodrigues JM, Luís AL, Lobato JV, Pinto MV, Faustino A, Hussain NS, Lopes MA, Veloso AP, Freitas M, Geuna S, Santos JD, Maurício AC. Intracellular Ca2+ concentration in the N1E-115 neuronal cell line and its use for peripheric nerve regeneration. ACTA MEDICA PORT 2005; 18:323-8. [PMID: 16611536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Entubulation repair of peripheral nerve injuries has a lengthy history. Several experimental and clinical studies have explored the effectiveness of many biodegradable and non-degradable tubes with or without addition of molecules and cells. The main objective of the present study was to develop an economical and also an easy way for culturing a neural cell line which is capable of growing, differentiating and producing locally nerve growth factors, that are otherwise extremely expensive, inside 90 PLA/10 PLG nerve guides. For this purpose the authors have chosen the N1E-115 cell line, a clone of cells derived from mouse neuroblastoma C-1300 with the perspective of using this differentiated cellular system to cover the inside of 90 PLA/10 PLG nerve guides placed to bridge a nerve gap of 10 mm in the rat sciatic nerve experimental model. The N1E-115 cells proliferate in normal culture medium but undergo neuronal differentiation in response to DMSO. Upon induction of differentiation, proliferation of N1E-115 cells ceases, extensive neurite outgrowth is observed and the membranes become highly excitable. While it is known that Ca2+ serves as an important intracellular signal for cellular various processes, such as growth and differentiation, be toxic to cells and be involved in the triggering of events leading to excitotoxic cell death in neurons. The [Ca2+]i in non-differentiated N1E-115 cells and after distinct periods of differentiation, have been determined by the epifluorescence technique using the Fura-2-AM probe. The results of this quantitative assessment, revealed that N1E-115 cells which undergo neuronal differentiation for 48 hours in the presence of 1.5% DMSO are best qualified to be used to cover the interior of the nerve guides since the [Ca2+]i was not found to be elevated indicating thus that the onset the cell death processes was not occurred.
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Affiliation(s)
- J M Rodrigues
- Centro de Estudos de Ciência Animal, Instituto de Ciências e Tecnologias Agrárias e Agro-Alimentares, Departamento de Clínicas Veterinárias, Universidade do Porto, Portugal
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Queiroz AC, Santos JD, Monteiro FJ. Development of a system to adsorb drugs onto calcium phosphate materials. J Mater Sci Mater Med 2005; 16:641-6. [PMID: 15965596 DOI: 10.1007/s10856-005-2535-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2003] [Accepted: 08/12/2004] [Indexed: 05/03/2023]
Abstract
Several studies were carried out in order to reduce the systemic use of antibiotics due to the high concentration required to provide the minimum inhibitory concentration (MIC) at infected sites. The aim of this study was to develop a system of drug adsorption onto commercial hydroxyapatite (HA, Ca10(PO4)6(OH)2) and glass reinforced hydroxyapatite (GR-HA) granules. The drug will then be released for the local treatment of periodontitis. The antibiotics used in this study were metronidazole, a specific antibiotic indicated for the systemic treatment of periodontitis, and ampicillin, a wide spectrum antibiotic. UV spectroscopy was used to measure the amount of drug adsorbed onto HA and GR-HA granules. Results showed that metronidazole was unable to adsorb on the material's surface, as opposed to ampicillin which adsorbed both onto HA and GR-HA. Preliminary release kinetics studies were carried out using a flow through dissolution system. Results are discussed in terms of the influence of the different surface characteristics of the materials on the adsorption processes.
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Affiliation(s)
- A C Queiroz
- INEB-Instituto de Engenharia Biomédica, Laboratório de Biomateriais, Rua do Campo Alegre 823, 4150-180, Porto, Portugal.
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Oliveira JM, Miyazaki T, Lopes MA, Ohtsuki C, Santos JD. Bonelike/PLGA hybrid materials for bone regeneration: preparation route and physicochemical characterisation. J Mater Sci Mater Med 2005; 16:253-259. [PMID: 15744617 DOI: 10.1007/s10856-005-6687-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2003] [Accepted: 06/23/2004] [Indexed: 05/24/2023]
Abstract
Bonelike/PLGA hybrid materials have been developed using gamma-MPS as silane-coupling agent between the inorganic and organic phases for controlled drug delivery applications. Silanization showed to be more effective when cyclohexane was used as a non-polar solvent (nP method) due to a chemical interaction between Bonelike, and the silane film, while by using a 95/5 (V/V) methanol/water as a polar solvent (P method), a much thinner film was achieved. Functional groups of PLGA, such as the carbonyl group (C=O), were identified using Raman and FTIR-ATR analysis and therefore these groups may be used to link therapeutic molecules. These novel hybrid materials prepared by combining silanization and post-hybridisation processes are expected to find use in medical applications of bone regeneration and as drug delivery carrier for therapeutic molecules.
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Affiliation(s)
- J M Oliveira
- INEB-Instituto de Engenharia Biomédica, Laboratório de Biomateriais, Rua do Campo Alegre, 823, 4150-180 Porto, Portugal
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