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Traeger L, Bedrikovetski S, Nguyen TM, Kwan YX, Lewis M, Moore JW, Sammour T. The impact of preoperative sarcopenia on postoperative ileus following colorectal cancer surgery. Tech Coloproctol 2023; 27:1265-1274. [PMID: 37184771 PMCID: PMC10638111 DOI: 10.1007/s10151-023-02812-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 04/24/2023] [Indexed: 05/16/2023]
Abstract
PURPOSE Sarcopenia is associated with poor short- and long-term patient outcomes following colorectal surgery. Despite postoperative ileus (POI) being a major complication following colorectal surgery, the predictive value of sarcopenia for POI is unclear. We assessed the association between sarcopenia and POI in patients with colorectal cancer. METHODS Elective colorectal cancer surgery patients were retrospectively included (2018-2022). The cross-sectional psoas area was calculated using preoperative staging imaging at the level of the 3rd lumbar vertebrae. Sarcopenia was determined using gender-specific cut-offs. The primary outcome POI was defined as not achieving GI-2 by day 4. Demographics, operative characteristics, and complications were compared via univariate and multivariate analyses. RESULTS Of 297 patients, 67 (22.6%) were sarcopenic. Patients with sarcopenia were older (median 74 (IQR 67-82) vs. 69 (58-76) years, p < 0.001) and had lower body mass index (median 24.4 (IQR 22.2-28.6) vs. 28.8 (24.9-31.9) kg/m2, p < 0.001). POI was significantly more prevalent in patients with sarcopenia (41.8% vs. 26.5%, p = 0.016). Overall rate of complications (85.1% vs. 68.3%, p = 0.007), Calvien-Dindo grade > 3 (13.4% vs. 10.0%, p = 0.026) and length of stay were increased in patients with sarcopenia (median 7 (IQR 5-12) vs. 6 (4-8) days, p = 0.013). Anastomotic leak rate was higher in patients with sarcopenia although the difference was not statistically significant (7.5% vs. 2.6%, p = 0.064). Multivariate analysis demonstrated sarcopenia (OR 2.0, 95% CI 1.1-3.8), male sex (OR 1.9, 95% CI 1.0-3.5), postoperative hypokalemia (OR 3.2, 95% CI 1.6-6.5) and increased opioid use (OR 2.4, 95% CI 1.3-4.3) were predictive of POI. CONCLUSION Sarcopenia demonstrates an association with POI. Future research towards truly identifying the predictive value of sarcopenia for postoperative complications could improve informed consent and operative planning for surgical patients.
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Affiliation(s)
- L Traeger
- Colorectal Unit, Department of Surgery, Royal Adelaide Hospital, Port Road, Adelaide, SA, 5000, Australia.
- Adelaide Medical School, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, SA, Australia.
| | - S Bedrikovetski
- Colorectal Unit, Department of Surgery, Royal Adelaide Hospital, Port Road, Adelaide, SA, 5000, Australia
- Adelaide Medical School, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, SA, Australia
| | - T M Nguyen
- Colorectal Unit, Department of Surgery, Royal Adelaide Hospital, Port Road, Adelaide, SA, 5000, Australia
| | - Y X Kwan
- Adelaide Medical School, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, SA, Australia
| | - M Lewis
- Colorectal Unit, Department of Surgery, Royal Adelaide Hospital, Port Road, Adelaide, SA, 5000, Australia
| | - J W Moore
- Colorectal Unit, Department of Surgery, Royal Adelaide Hospital, Port Road, Adelaide, SA, 5000, Australia
- Adelaide Medical School, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, SA, Australia
| | - T Sammour
- Colorectal Unit, Department of Surgery, Royal Adelaide Hospital, Port Road, Adelaide, SA, 5000, Australia
- Adelaide Medical School, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, SA, Australia
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2
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Nguyen TM, Chen HH, Chang YC, Ning TC, Chen KF. Remediation of groundwater contaminated with trichloroethylene (TCE) using a long-lasting persulfate/biochar barrier. Chemosphere 2023; 333:138954. [PMID: 37201606 DOI: 10.1016/j.chemosphere.2023.138954] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 05/08/2023] [Accepted: 05/14/2023] [Indexed: 05/20/2023]
Abstract
Groundwater contamination by chlorinated solvents causes potential threats to water resources and human health. Therefore, it is important to develop effective technologies to remediate contaminated groundwater. This study uses biodegradable hydrophilic polymers, hydroxypropyl methylcellulose (HPMC), hydroxyethyl cellulose (HEC) and polyvinyl pyrrolidone (PVP) as binders to manufacture persulfate (PS) tablets for the sustained release of persulfate to treat trichloroethylene (TCE) in groundwater. The release time for different tablets decreases in the order: HPMC (8-15 days) > HEC (7-8 days) > PVP (2-5 days). The efficiency with which persulfate is released is: HPMC (73-79%) > HEC (60-72%) > PVP (12-31%). HPMC is the optimal binder for the manufacture of persulfate tablets and persulfate is released from a tablet of HPMC/PS ratio (wt/wt) of 4/3 for 15 days at a release rate of 1127 mg/day. HPMC/PS/biochar (BC) ratios (wt/wt/wt) between 1/1/0.02 and 1/1/0.0333 are suitable for PS/BC tablets. PS/BC tablets release persulfate for 9-11 days at release rates of 1243 to 1073 mg/day. The addition of too much biochar weakens the structure of the tablets, which results in a rapid release of persulfate. TCE is oxidized by a PS tablet with an efficiency of 85% and a PS/BC tablet eliminates more TCE, with a removal efficiency of 100%, due to oxidation and adsorption during the 15 days of reaction. Oxidation is the predominant mechanism for TCE elimination by a PS/BC tablet. The adsorption of TCE by BC fits well with the pseudo-second-order kinetics and the pseudo-first-order kinetics, which describes the removal of TCE by PS and PS/BC tablets. The results of this study show that a PS/BC tablet can be used in a permeable reactive barrier for long-term passive remediation of groundwater.
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Affiliation(s)
- Thi-Manh Nguyen
- Department of Civil Engineering, National Chi Nan University, Puli, Nantou, 545301, Taiwan
| | - Hung-Hsiang Chen
- Department of Civil Engineering, National Chi Nan University, Puli, Nantou, 545301, Taiwan
| | - Yu-Chen Chang
- Department of Civil Engineering, National Chi Nan University, Puli, Nantou, 545301, Taiwan
| | - Tzu-Chien Ning
- Department of Civil Engineering, National Chi Nan University, Puli, Nantou, 545301, Taiwan
| | - Ku-Fan Chen
- Department of Civil Engineering, National Chi Nan University, Puli, Nantou, 545301, Taiwan.
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3
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Mnikhovich MV, Romanov AV, Nguyen TM, Bezuglova TV, Pastukhova DA. Histological and electron microscopic features of the extracellular matrix of invasive breast ductal carcinoma of no special type. Report of 5 cases and literature review. Ultrastruct Pathol 2023:1-10. [PMID: 37159559 DOI: 10.1080/01913123.2023.2209162] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Invasive ductal carcinoma of no special type is the most common type of breast cancer. In light of the above, many authors have reported the histological and electron microscopic characteristics of these tumors. On the other hand, a limited number of works exist where the authors have concentrated on investigating the extracellular matrix. This article presents data received as the results of light and electron microscopic examination of the extracellular matrix, angiogenesis, and cellular microenvironment of invasive breast ductal carcinoma of no special type. The authors have shown that the processes of stroma formation in the IDC NOS type are associated with the presence of fibroblasts, macrophages, dendritic cells, lymphocytes, and other cells. It was also shown the detailed interaction of the above cells with each other, as well as with vessels and fibrillar proteins such as collagen and elastin. The microcirculatory component is characterized by histophysiological heterogeneity, which manifests as the activation of angiogenesis, relative vascular differentiation, and regression of individual microcirculation components.
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Affiliation(s)
- M V Mnikhovich
- Avtsyn Research Institute of Human Morphology of Federal state budgetary scientific institution "Petrovsky National Research Centre of Surgery", Moscow, Russian Federation
| | - A V Romanov
- Avtsyn Research Institute of Human Morphology of Federal state budgetary scientific institution "Petrovsky National Research Centre of Surgery", Moscow, Russian Federation
- Unim LLC, Moscow, Russia
| | - T M Nguyen
- Avtsyn Research Institute of Human Morphology of Federal state budgetary scientific institution "Petrovsky National Research Centre of Surgery", Moscow, Russian Federation
| | - T V Bezuglova
- Avtsyn Research Institute of Human Morphology of Federal state budgetary scientific institution "Petrovsky National Research Centre of Surgery", Moscow, Russian Federation
| | - D A Pastukhova
- National Medical Research Center for Endocrinology, Moscow, Russia
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4
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Nguyen TM, Tonmukayakul U, Calache H. Dental Restrictions to Clinical Practice during the COVID-19 Pandemic: An Australian Perspective. JDR Clin Trans Res 2021; 6:291-294. [PMID: 33632001 DOI: 10.1177/23800844211000341] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
KNOWLEDGE TRANSFER STATEMENT The reportedly low COVID-19 transmission occurring in dental settings highlight achievements made by the dental profession. There are valid reasons to reconsider risk-based essential oral healthcare during the COVID-19 pandemic.
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Affiliation(s)
- T M Nguyen
- Deakin Health Economics, Institute for Health Transformation, Deakin University, Geelong, VIC, Australia.,Community Dental Program, Peninsula Health, Frankston, VIC, Australia.,Coburg Hill Oral Care, Coburg North, VIC, Australia
| | - U Tonmukayakul
- Deakin Health Economics, Institute for Health Transformation, Deakin University, Geelong, VIC, Australia
| | - H Calache
- Deakin Health Economics, Institute for Health Transformation, Deakin University, Geelong, VIC, Australia.,Dentistry and Oral Health, La Trobe Rural Health School, La Trobe University, Flora Hill, VIC, Australia
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5
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Affiliation(s)
- T M Nguyen
- Département of Anaesthesiology, Seclin Carvin Hospital center, 59113 Seclin, France.
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6
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Salte IM, Oestvik A, Smistad E, Melichova D, Nguyen TM, Brunvand H, Edvardsen T, Loevstakken L, Grenne B. 545 Deep learning/artificial intelligence for automatic measurement of global longitudinal strain by echocardiography. Eur Heart J Cardiovasc Imaging 2020. [DOI: 10.1093/ehjci/jez319.279] [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] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Funding Acknowledgements
The Norwegian Health Association, South-Eastern Norway regional health Authority and the national program for clinical therapy research (KLINBEFORSK).
Background
Global longitudinal strain (GLS) by echocardiography has incremental prognostic value in patients with acute myocardial infarction and heart failure compared to left ventricular (LV) ejection fraction and provides more reproducible measurements of LV function. Recent advances in machine learning for image analysis now open the possibility for robust fully automated tracing of the LV and measurement of global longitudinal strain (GLS), without any operator input. This could make real-time GLS possible and remove inter-reader variability, thus resulting in saved time and improved test-retest reliability. The aim of the present study was to investigate how measurements by this novel automatic method compares to conventional speckle tracking analyses of GLS.
Methods
100 transthoracic echocardiographic examinations were included from a clinical database of patients with acute myocardial infarction or de-novo heart failure. Examinations were included consecutively and regardless of image quality. Simpson biplane LV ejection fraction ranged from 7 to 70%. Images of three standard apical planes from each examination were analysed using our novel and fully automated GLS method based on deep learning technology. The automated GLS measurements were compared to conventional speckle tracking GLS measurements of the same acquisitions using vendor specific format and software (EchoPAC, GE Healthcare), performed by a single experienced observer.
Results
GLS was -11.6 ± 4.5% and -12.8 ± 5.0% for the deep learning method and the conventional method, respectively. Bland-Altman analysis showed a bias of -0.7 ± 1,9% and 95% limits of agreement of -4,6 to 3.1. No clear value dependent bias was found by visual inspection (Figure A). Feasibility for measurement of GLS was 93% for the deep learning based method and 99% for the conventional method. The limits of agreement found in our study is comparable to findings in the intervendor comparison study by the EASCVI/ASE/Industry Task force to standardize deformation imaging.
Conclusion
This novel deep learning based method succeeds without any operator input to automatically identify and classify the three apical standard views, trace the myocardium, perform motion estimation and measure global longitudinal strain. This could further facilitate the clinical use of GLS as an important tool for enhancing clinical decision-making.
Abstract 545 Figure.
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Affiliation(s)
- I M Salte
- Hospital of Southern Norway, Department of Medicine, Kristiansand, Norway
| | - A Oestvik
- Norwegian University of Science and Technology, Department of Circulation and Medical Imaging, Trondheim, Norway
| | - E Smistad
- Norwegian University of Science and Technology, Department of Circulation and Medical Imaging, Trondheim, Norway
| | - D Melichova
- Hospital of Southern Norway, Department of Medicine, Arendal, Norway
| | - T M Nguyen
- Hospital of Southern Norway, Department of Medicine, Kristiansand, Norway
| | - H Brunvand
- Hospital of Southern Norway, Department of Medicine, Arendal, Norway
| | - T Edvardsen
- Oslo University Hospital, Department of Cardiology, Oslo, Norway
| | - L Loevstakken
- Norwegian University of Science and Technology, Department of Circulation and Medical Imaging, Trondheim, Norway
| | - B Grenne
- St Olavs Hospital, Clinic of Cardiology, Trondheim, Norway
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7
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Melichova D, Nguyen TM, Salte IM, Klaebo LG, Sjoli B, Karlsen S, Dahlslett T, Leren IS, Edvardsen T, Brunvand H, Haugaa KH. P1428 Mortality in non-ischemic cardiomyopathy is low and close to the general population. Eur Heart J Cardiovasc Imaging 2020. [DOI: 10.1093/ehjci/jez319.857] [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: 11/15/2022] Open
Abstract
Abstract
Funding Acknowledgements
South Eastern Norway regional health authority
Background
Patients with non-ischemic dilated cardiomyopathy (NDCM) have lower mortality compared to patients with ischemic cardiomyopathy (ICM). Recent reports suggest less benefit of a primary prophylactic implantable cardioverter defibrillator (ICD) in NDCM.
Purpose
We aimed to investigate mortality rate and appropriate ICD therapy in a consecutive cohort of patients with NDCM and ICM.
Methods
In this prospective multi-center study, we consecutively included NDCM and ICM patients with left ventricular ejection fraction (LVEF) < 40% from July 2014 to January 2018. ICM or NDCM classification was based on coronary angiography. Echocardiography was performed at inclusion and LVEF and global longitudinal strain (GLS) were assessed. All-cause mortality and primary prevention ICD therapies were recorded during follow-up.
Results
We included 290 patients (67 ± 13 years old, 74% males), 207 with ICM and 83 with NDCM. At inclusion LVEF was 31 ± 6% and GLS -10.5 ± -3.3%. Patients with ICM were older (68 ± 12 years vs. 63 ± 15 years, p < 0.01), had better LVEF (32 ± 6% vs. 28 ± 7%, p < 0.01), and shorter QRS duration (106 ± 23 ms vs. 122 ± 28 ms, p < 0.01). A primary prevention ICD was implanted in 18 (9%) ICM patients and in 21 (25%) NDCM patients (p < 0.001).
During 22 ±12 months follow up, all-cause mortality was 27 (9%) in the entire population. In patients with ICM 1/18 (6%) received appropriate shock from their primary prevention ICD compared to 3/21 (14%) NDCM patients. Mortality was more frequent in ICM; 26/207 (13%) compared to 1/83 (1.2%) in NDCM (Log rank p < 0.01). All-cause mortality or appropriate ICD shock was more frequent in ICM compared to NDCM (27 (13%) vs. 4 (5%) log rank p = 0.02) (Figure). Assuming the arrhythmias treated by the ICD shocks would have been lethal, annual mortality of 2.5% in the NDCM population was only slightly higher compared to the age matched general population (1% annual mortality) (blue line).
Conclusion
Patients with NDCM had better survival, and in general a lower event rate, compared to patients with ICM. However, subgroups of NDCM patients may benefit from their primary prophylactic ICD and further studies should investigate the need of primary prevention ICD in patients with NDCM.
Abstract P1428 Figure.
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Affiliation(s)
| | | | | | - L G Klaebo
- Oslo University Hospital Rikshospitalet, Oslo, Norway
| | - B Sjoli
- Sorlandet Hospital, Arendal, Norway
| | | | | | - I S Leren
- Oslo University Hospital Rikshospitalet, Oslo, Norway
| | - T Edvardsen
- Oslo University Hospital Rikshospitalet, Oslo, Norway
| | | | - K H Haugaa
- Oslo University Hospital Rikshospitalet, Oslo, Norway
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8
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Nguyen TM, Caruhel JB, Khonsari RH. A subperiosteal maxillary implant causing severe osteolysis. J Stomatol Oral Maxillofac Surg 2018; 119:523-525. [PMID: 29940264 DOI: 10.1016/j.jormas.2018.06.007] [Citation(s) in RCA: 6] [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] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 05/21/2018] [Accepted: 06/17/2018] [Indexed: 11/26/2022]
Abstract
Subperiosteal implant denture therapy was initially introduced in 1942 in Sweden and was subsequently used worldwide for the treatment of fully edentulous maxillary or mandibular arches with advanced bone atrophy. Most authors describe decent success rates for mandibular subperiosteal implants in cases with major bone atrophy but follow-up studies for maxillary subperiosteal implants are not available. Here, we report a case of severe maxillary osteolysis secondary to the placement of a subperiosteal in-house implant. Subperiosteal implants are rarely used today but patients still carrying these devices can be challenging to manage when severe complications occur. New technical advances, including the use of surgical planification and additive manufacturing, may lead to a new interest in subperiosteal implants.
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Affiliation(s)
- T M Nguyen
- Service de chirurgie maxillofaciale et plastique, hôpital universitaire Necker-Enfants-Malades, université Sorbonne Paris Cité, université Paris Descartes, Assistance publique-Hôpitaux de Paris, 149, rue de Sèvres, 75015 Paris, France
| | - J-B Caruhel
- Service de chirurgie maxillofaciale et stomatologie, hôpital universitaire Pitié-Salpêtrière, Sorbonne université, université Pierre-et-Marie-Curie, Assistance publique-Hôpitaux de Paris, 47-83 boulevard de l'Hôpital, 75013 Paris, France
| | - R H Khonsari
- Service de chirurgie maxillofaciale et plastique, hôpital universitaire Necker-Enfants-Malades, université Sorbonne Paris Cité, université Paris Descartes, Assistance publique-Hôpitaux de Paris, 149, rue de Sèvres, 75015 Paris, France.
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9
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Ma C, Dutton SJ, Cipriano LE, Singh S, Parker CE, Nguyen TM, Guizzetti L, Gregor JC, Chande N, Hindryckx P, Feagan BG, Jairath V. Systematic review with meta-analysis: prevalence, risk factors and costs of aminosalicylate use in Crohn's disease. Aliment Pharmacol Ther 2018; 48:114-126. [PMID: 29851091 DOI: 10.1111/apt.14821] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [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] [Received: 03/25/2018] [Revised: 04/13/2018] [Accepted: 05/02/2018] [Indexed: 12/22/2022]
Abstract
BACKGROUND Aminosalicylates are the most frequently prescribed drugs for patients with Crohn's disease (CD), yet evidence to support their efficacy as induction or maintenance therapy is controversial. AIMS To quantify aminosalicylate use in CD clinical trials, identify factors associated with use and estimate direct annual treatment costs of therapy. METHODS MEDLINE, Embase and CENTRAL were searched to April 2017 for placebo-controlled trials in adults with CD treated with corticosteroids, immunosuppressants or biologics. The proportion of patients co-prescribed aminosalicylates in placebo arms was pooled using a random-effects model. Meta-regression was used to identify factors associated with aminosalicylate use. Annual treatment costs were estimated using the 2016 Ontario Drug Benefit Program. RESULTS Forty-two induction and 10 maintenance trials were included. The pooled proportion of patients co-prescribed aminosalicylates was 44% [95% CI: 39%-49%] in induction trials and 49% [95% CI: 35%-64%] in maintenance trials. There was substantial to considerable heterogeneity (I2 = 86.0%, 91.8% for induction and maintenance trials, respectively). In multivariable meta-regression, aminosalicylate use has decreased over time in induction trials (OR 0.50 [95% CI: 0.34-0.74] per 10-year increment). While a decline has been seen over time, 35% of CD patients were still using aminosalicylates in contemporary trials from the last 5 years. The estimated annual cost for the lowest price mesalazine (mesalamine) formulation is approximately $32 million for the Canadian CD population. CONCLUSIONS Over one-third of CD patients entering clinical trials are still co-prescribed aminosalicylates. A definitive trial is needed to inform the conventional practice of using aminosalicylates as CD maintenance therapy.
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Affiliation(s)
- C Ma
- Division of Gastroenterology and Hepatology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Robarts Clinical Trials, Western University, London, ON, Canada
| | - S J Dutton
- Oxford Clinical Trials Research Unit and Centre for Statistics in Medicine, Nuffield Department of Orthopedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK
| | - L E Cipriano
- Department of Epidemiology and Biostatistics, Western University, London, ON, Canada.,Ivey Business School, Western University, London, ON, Canada
| | - S Singh
- Division of Biomedical Informatics, University of California San Diego, La Jolla, CA, USA.,Division of Gastroenterology, University of California San Diego, La Jolla, CA, USA
| | - C E Parker
- Robarts Clinical Trials, Western University, London, ON, Canada
| | - T M Nguyen
- Robarts Clinical Trials, Western University, London, ON, Canada
| | - L Guizzetti
- Robarts Clinical Trials, Western University, London, ON, Canada
| | - J C Gregor
- Division of Gastroenterology, Department of Medicine, Western University, London, ON, Canada
| | - N Chande
- Division of Gastroenterology, Department of Medicine, Western University, London, ON, Canada
| | - P Hindryckx
- Department of Gastroenterology, University Hospital of Ghent, Ghent, Belgium
| | - B G Feagan
- Robarts Clinical Trials, Western University, London, ON, Canada.,Department of Epidemiology and Biostatistics, Western University, London, ON, Canada.,Division of Gastroenterology, Department of Medicine, Western University, London, ON, Canada
| | - V Jairath
- Robarts Clinical Trials, Western University, London, ON, Canada.,Department of Epidemiology and Biostatistics, Western University, London, ON, Canada.,Division of Gastroenterology, Department of Medicine, Western University, London, ON, Canada
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10
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Ma C, Guizzetti L, Panaccione R, Fedorak RN, Pai RK, Parker CE, Nguyen TM, Khanna R, Vande Casteele N, D'Haens G, Sandborn WJ, Feagan BG, Jairath V. Systematic review with meta-analysis: endoscopic and histologic placebo rates in induction and maintenance trials of ulcerative colitis. Aliment Pharmacol Ther 2018; 47:1578-1596. [PMID: 29696670 DOI: 10.1111/apt.14672] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [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] [Received: 12/15/2017] [Revised: 01/17/2018] [Accepted: 03/27/2018] [Indexed: 02/06/2023]
Abstract
BACKGROUND Regulatory requirements for claims of mucosal healing in ulcerative colitis (UC) will require demonstration of both endoscopic and histologic healing. Quantifying these rates is essential for future drug development. AIMS To meta-analyse endoscopic and histologic placebo response and remission rates in UC randomised controlled trials (RCTs) and identify factors influencing these rates. METHODS MEDLINE, EMBASE and the Cochrane Library were searched from inception to March 2017 for placebo-controlled trials of pharmacological interventions for UC. Endoscopic and histologic placebo rates were pooled by random effects. Mixed effects univariable and multivariable meta-regression was used to evaluate the influence of patient, intervention and trial-related study-level covariates on these rates. RESULTS Fifty-six induction (placebo n = 4171) and 8 maintenance trials (placebo n = 1011) were included. Pooled placebo endoscopic remission and response rates for induction trials were 23% [95 confidence interval (CI) 19-28%] and 35% [95% CI 27-42%] respectively, and 20% [95% CI 16-24%] for maintenance of remission. The pooled histologic placebo remission rate was 14% [95% CI 8-22%] for induction trials. High heterogeneity was observed for all outcomes (I2 56.2%-88.3%). On multivariable meta-regression, central endoscopy reading was associated with significantly lower endoscopic placebo remission rates (16% vs 25%; OR = 0.52, [95% CI 0.29-0.92], P = 0.03). On univariable meta-regression, higher histologic placebo remission was associated with concomitant corticosteroids (OR = 1.17 [95% CI 1.08-1.26], P < 0.0001, per 10% increase in corticosteroid use). CONCLUSIONS Placebo endoscopic and histologic rates range from 14% to 35% in UC RCTs but are highly heterogeneous. Outcome standardisation may reduce heterogeneity and is needed in this field.
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Affiliation(s)
- C Ma
- Division of Gastroenterology and Hepatology, University of Calgary, Calgary, AB, Canada.,Robarts Clinical Trials, Western University, London, ON, Canada
| | - L Guizzetti
- Robarts Clinical Trials, Western University, London, ON, Canada
| | - R Panaccione
- Division of Gastroenterology and Hepatology, University of Calgary, Calgary, AB, Canada
| | - R N Fedorak
- Division of Gastroenterology, University of Alberta, Edmonton, AB, Canada
| | - R K Pai
- Robarts Clinical Trials, Western University, London, ON, Canada.,Department of Pathology and Laboratory Medicine, Mayo Clinic Arizona, Scottsdale, AZ, USA
| | - C E Parker
- Robarts Clinical Trials, Western University, London, ON, Canada
| | - T M Nguyen
- Robarts Clinical Trials, Western University, London, ON, Canada
| | - R Khanna
- Robarts Clinical Trials, Western University, London, ON, Canada.,Department of Medicine, Western University, London, ON, Canada
| | - N Vande Casteele
- Robarts Clinical Trials, Western University, London, ON, Canada.,Division of Gastroenterology, University of California San Diego, La Jolla, CA, USA
| | - G D'Haens
- Robarts Clinical Trials, Western University, London, ON, Canada.,Inflammatory Bowel Disease Centre, Academic Medical Centre, Amsterdam, The Netherlands
| | - W J Sandborn
- Robarts Clinical Trials, Western University, London, ON, Canada.,Division of Gastroenterology, University of California San Diego, La Jolla, CA, USA
| | - B G Feagan
- Robarts Clinical Trials, Western University, London, ON, Canada.,Department of Medicine, Western University, London, ON, Canada.,Department of Epidemiology and Biostatistics, Western University, London, ON, Canada
| | - V Jairath
- Robarts Clinical Trials, Western University, London, ON, Canada.,Department of Medicine, Western University, London, ON, Canada.,Department of Epidemiology and Biostatistics, Western University, London, ON, Canada
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11
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Trinh VH, Nguyen TH, To TMD, Nguyen TM, Tran TTH, Nguyen VC. Species composition and level of infestation of cockroaches in three areas in Hanoi. Trop Biomed 2016; 33:500-505. [PMID: 33579122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A study on the species composition and the level of infestation of cockroaches was carried out from April 2013 to October 2014 in three localities of Hanoi, Vietnam, namely the Lan Ong-Old Town, Linh Dam condominium and Tan Da Resort. Out of the 187 units of premises examined, 44.9% of units were infested with cockroaches. A total of 576 cockroaches were trapped, of which six species were identified: Periplaneta americana (L.) was the most dominant species (72.1%), followed by Blattella germanica (L.) (14.8%), Pycnoscelus surinamensis (L.) (7.3%), Periplaneta australasiae (Fabricius) (2.9%), Periplaneta fuliginosa (Serville) (1.9%) and Supella longipalpa (Fabricius) (1.0%). Infestation was the highest in Lan Ong (74.0%), followed by Linh Dam (40.5%) and Tan Da (25.9%). Cockroaches were abundantly found in warehouses (100%), electrical distribution room (56.3%), and kitchens (46.7%).
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Affiliation(s)
- V H Trinh
- Institute of Ecology and Works Protection, 267 Chua Boc, Dong Da, Hanoi, Vietnam
| | - T H Nguyen
- Institute of Ecology and Works Protection, 267 Chua Boc, Dong Da, Hanoi, Vietnam
| | - T M D To
- Institute of Ecology and Works Protection, 267 Chua Boc, Dong Da, Hanoi, Vietnam
| | - T M Nguyen
- Institute of Ecology and Works Protection, 267 Chua Boc, Dong Da, Hanoi, Vietnam
| | - T T H Tran
- Institute of Ecology and Works Protection, 267 Chua Boc, Dong Da, Hanoi, Vietnam
| | - V C Nguyen
- National Institute of Malariology Parasitology and Entomology, 35 Trung Van, phuong Trung Van, quan Nam Tu Liem, Hanoi, Vietnam
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Boldt K, Van Reeuwijk J, Lu Q, Koutroumpas K, Horn N, Beersum SV, Texier Y, Nguyen TM, Willer JR, Katsanis N, Képès F, Russell RB, Ueffing M, Roepman R. Systematic exploration of the ciliary protein landscape by large-scale affinity proteomics. Cilia 2015. [PMCID: PMC4519120 DOI: 10.1186/2046-2530-4-s1-p89] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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13
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Goff MG, Lambers FM, Nguyen TM, Sung J, Rimnac CM, Hernandez CJ. Fatigue-induced microdamage in cancellous bone occurs distant from resorption cavities and trabecular surfaces. Bone 2015; 79:8-14. [PMID: 26008609 PMCID: PMC4501884 DOI: 10.1016/j.bone.2015.05.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 04/29/2015] [Accepted: 05/15/2015] [Indexed: 10/23/2022]
Abstract
Impaired bone toughness is increasingly recognized as a contributor to fragility fractures. At the tissue level, toughness is related to the ability of bone tissue to resist the development of microscopic cracks or other tissue damage. While most of our understanding of microdamage is derived from studies of cortical bone, the majority of fragility fractures occur in regions of the skeleton dominated by cancellous bone. The development of tissue microdamage in cancellous bone may differ from that in cortical bone due to differences in microstructure and tissue ultrastructure. To gain insight into how microdamage accumulates in cancellous bone we determined the changes in number, size and location of microdamage sites following different amounts of cyclic compressive loading. Human vertebral cancellous bone specimens (n=32, 10 male donors, 6 female donors, age 76 ± 8.8, mean ± SD) were subjected to sub-failure cyclic compressive loading and microdamage was evaluated in three-dimensions. Only a few large microdamage sites (the largest 10%) accounted for 70% of all microdamage caused by cyclic loading. The number of large microdamage sites was a better predictor of reductions in Young's modulus caused by cyclic loading than overall damage volume fraction (DV/BV). The majority of microdamage volume (69.12 ± 7.04%) was located more than 30 μm (the average erosion depth) from trabecular surfaces, suggesting that microdamage occurs primarily within interstitial regions of cancellous bone. Additionally, microdamage was less likely to be near resorption cavities than other bone surfaces (p<0.05), challenging the idea that stress risers caused by resorption cavities influence fatigue failure of cancellous bone. Together, these findings suggest that reductions in apparent level mechanical performance during fatigue loading are the result of only a few large microdamage sites and that microdamage accumulation in fatigue is likely dominated by heterogeneity in tissue material properties rather than stress concentrations caused by micro-scale geometry.
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Affiliation(s)
- M G Goff
- Department of Biomedical Engineering, Cornell University, Ithaca, NY, USA; Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA
| | - F M Lambers
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA
| | - T M Nguyen
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA
| | - J Sung
- College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - C M Rimnac
- Departments of Mechanical and Aerospace Engineering and Orthopaedics, Case Western Reserve University, Cleveland, OH, USA
| | - C J Hernandez
- Department of Biomedical Engineering, Cornell University, Ithaca, NY, USA; Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA; Hospital for Special Surgery, New York City, NY, USA.
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14
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Voloc A, Esterle L, Nguyen TM, Walrant-Debray O, Colofitchi A, Jehan F, Garabedian M. High prevalence of genu varum/valgum in European children with low vitamin D status and insufficient dairy products/calcium intakes. Eur J Endocrinol 2010; 163:811-7. [PMID: 20739417 DOI: 10.1530/eje-10-0434] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [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: 11/08/2022]
Abstract
OBJECTIVE The prevalence of lower limb deformities physiologically decreases after 5 years of age. It remains high in some tropical and subtropical regions where it has been associated with severe vitamin D deficiency, low calcium/milk intakes, malnutrition, and/or fluoride overexposure. Very little data is available in apparently healthy Caucasian children and adolescents. DESIGN We evaluated the prevalence of genu varum/valgum and other clinical symptoms, and assessed vitamin D status and markers of calcium metabolism in 226 apparently healthy European full-time boarders (7-16 years) seen during winter-spring and fed a cereal-based diet with little access to meat, milk, and dairy products. A cohort of 71 white children and adolescents hospitalized for acute illness served as age-matched controls. RESULTS Association studies showed a high prevalence of lower limb deformities (36%) and higher alkaline phosphate activities in the 21% of children and adolescent full-time boarders with serum 25-(OH)D levels ≤ 30 nmol/l, and low serum calcium in the 74% of boarders with 25-(OH)D levels ≤ 50 nmol/l, compared with boarders with higher vitamin D status. No such anomalies were found in the control cohort despite lower serum 25-(OH)D levels. CONCLUSIONS Low 25-(OH)D levels, at least during winter-spring, combined with additional risk factors such as very low calcium/milk intakes and possibly digestive disorders, are associated with an increased risk of genu varum/valgum in European children and adolescents. Thus, dietary fortification, or supplementation with vitamin D, may be recommended, at least during the winter, to European children and adolescents with either none or insufficient calcium/dairy product intakes.
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Affiliation(s)
- A Voloc
- University of Medicine and Pharmacy Nicolae Testemitanu, Chisinau, MD 2001 Moldova
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15
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Voloc A, Esterle L, Nguyen TM, Walrant-Debray O, Colofitchi A, Jehan F, Garabedian M. High prevalence of genu varum/valgum in European children with low vitamin D status and insufficient dairy products/calcium intakes. Eur J Endocrinol 2010. [PMID: 20739417 DOI: 101530/eje-10-0434] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE The prevalence of lower limb deformities physiologically decreases after 5 years of age. It remains high in some tropical and subtropical regions where it has been associated with severe vitamin D deficiency, low calcium/milk intakes, malnutrition, and/or fluoride overexposure. Very little data is available in apparently healthy Caucasian children and adolescents. DESIGN We evaluated the prevalence of genu varum/valgum and other clinical symptoms, and assessed vitamin D status and markers of calcium metabolism in 226 apparently healthy European full-time boarders (7-16 years) seen during winter-spring and fed a cereal-based diet with little access to meat, milk, and dairy products. A cohort of 71 white children and adolescents hospitalized for acute illness served as age-matched controls. RESULTS Association studies showed a high prevalence of lower limb deformities (36%) and higher alkaline phosphate activities in the 21% of children and adolescent full-time boarders with serum 25-(OH)D levels ≤ 30 nmol/l, and low serum calcium in the 74% of boarders with 25-(OH)D levels ≤ 50 nmol/l, compared with boarders with higher vitamin D status. No such anomalies were found in the control cohort despite lower serum 25-(OH)D levels. CONCLUSIONS Low 25-(OH)D levels, at least during winter-spring, combined with additional risk factors such as very low calcium/milk intakes and possibly digestive disorders, are associated with an increased risk of genu varum/valgum in European children and adolescents. Thus, dietary fortification, or supplementation with vitamin D, may be recommended, at least during the winter, to European children and adolescents with either none or insufficient calcium/dairy product intakes.
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Affiliation(s)
- A Voloc
- University of Medicine and Pharmacy Nicolae Testemitanu, Chisinau, MD 2001 Moldova
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Alvarez-Buylla A, Kohwi M, Nguyen TM, Merkle FT. The heterogeneity of adult neural stem cells and the emerging complexity of their niche. Cold Spring Harb Symp Quant Biol 2008; 73:357-365. [PMID: 19022766 DOI: 10.1101/sqb.2008.73.019] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Neural stem cells persist in the adult mammalian brain in a neurogenic niche known as the subventricular zone (SVZ). SVZ neural stem cells (NSCs) can self-renew and are multipotent in culture. In rodents, adult NSCs correspond to SVZ astrocytes (type B cells) that are derived from radial glia, the NSCs of the embryonic and early postnatal brain. Type B cells generate transit-amplifying (type C) cells that give rise to young neurons (type A cells) and oligodendrocytes. Young neurons are born throughout the adult neurogenic niche and migrate tangentially through a complex network of chains that merge into the rostral migratory stream (RMS), a major pathway that leads into the olfactory bulb (OB). Within the OB, young neurons differentiate into multiple types of interneurons. The SVZ was thought to be limited to the lateral wall of the lateral ventricle, but recent work shows that the adult neurogenic niche is significantly more extensive and includes portions of the medial and dorsal walls of the lateral ventricle and the RMS itself. Furthermore, several recent studies explain why young OB neurons are generated in such an extensive region. Type B cells in different regions of the SVZ, although able to self-renew and generate both neurons and glial cells in vitro, are heterogeneous and committed to producing defined neuronal subtypes in vivo. The adult SVZ therefore provides a rich system to study not only neural replacement, but also the cellular and molecular mechanisms underlying regionalization and cell-fate specification.
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Affiliation(s)
- A Alvarez-Buylla
- Department of Neurological Surgery and Institute for Regeneration Medicine, University of California, San Francisco, California 94143, USA
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17
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Gregory A, Westaway SK, Holm IE, Kotzbauer PT, Hogarth P, Sonek S, Coryell JC, Nguyen TM, Nardocci N, Zorzi G, Rodriguez D, Desguerre I, Bertini E, Simonati A, Levinson B, Dias C, Barbot C, Carrilho I, Santos M, Malik I, Gitschier J, Hayflick SJ. Neurodegeneration associated with genetic defects in phospholipase A(2). Neurology 2008; 71:1402-9. [PMID: 18799783 DOI: 10.1212/01.wnl.0000327094.67726.28] [Citation(s) in RCA: 205] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE Mutations in the gene encoding phospholipase A(2) group VI (PLA2G6) are associated with two childhood neurologic disorders: infantile neuroaxonal dystrophy (INAD) and idiopathic neurodegeneration with brain iron accumulation (NBIA). INAD is a severe progressive psychomotor disorder in which axonal spheroids are found in brain, spinal cord, and peripheral nerves. High globus pallidus iron is an inconsistent feature of INAD; however, it is a diagnostic criterion of NBIA, which describes a clinically and genetically heterogeneous group of disorders that share this hallmark feature. We sought to delineate the clinical, radiographic, pathologic, and genetic features of disease resulting from defective phospholipase A(2). METHODS We identified 56 patients clinically diagnosed with INAD and 23 with idiopathic NBIA and screened their DNA for PLA2G6 mutations. RESULTS Eighty percent of patients with INAD had mutations in PLA2G6, whereas mutations were found in only 20% of those with idiopathic NBIA. All patients with two null mutations had a more severe phenotype. On MRI, nearly all mutation-positive patients had cerebellar atrophy, and half showed brain iron accumulation. We observed Lewy bodies and neurofibrillary tangles in association with PLA2G6 mutations. CONCLUSION Defects in phospholipase A(2) lead to a range of phenotypes. PLA2G6 mutations are associated with nearly all cases of classic infantile neuroaxonal dystrophy but a minority of cases of idiopathic neurodegeneration with brain iron accumulation, and genotype correlates with phenotype. Cerebellar atrophy predicts which patients are likely to be mutation-positive. The neuropathologic changes that are caused by defective phospholipase A(2) suggest a shared pathogenesis with both Parkinson and Alzheimer diseases.
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Affiliation(s)
- A Gregory
- Department of Molecular and Medical Genetics, Oregon Health & Science University, L103a, 3181 SW Sam Jackson Park Rd., Portland, OR 97239-3098, USA
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18
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Sedgwick SG, Morgan BA, Nguyen TM, Morris GE. An improved method for mapping epitopes of recombinant antigens by transposon mutagenesis. Methods Mol Biol 2003; 66:343-53. [PMID: 8959726 DOI: 10.1385/0-89603-375-9:343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- S G Sedgwick
- Yeast Genetics Division, National Institute for Medical Research, London, UK
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19
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Affiliation(s)
- T M Nguyen
- Research Division, North East Wales Institute, Wrexham, UK
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20
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Nguyen TM, Adiceam P, Kottler ML, Guillozo H, Rizk-Rabin M, Brouillard F, Lagier P, Palix C, Garnier JM, Garabedian M. Tryptophan missense mutation in the ligand-binding domain of the vitamin D receptor causes severe resistance to 1,25-dihydroxyvitamin D. J Bone Miner Res 2002; 17:1728-37. [PMID: 12211444 DOI: 10.1359/jbmr.2002.17.9.1728] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [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: 11/18/2022]
Abstract
In this study, two related young children, brother and sister, exhibited severe vitamin D-resistant rickets without alopecia. Sequence analysis of the total vitamin D receptor (VDR) cDNA from skin fibroblasts revealed a substitution of the unique tryptophan of the VDR by arginine at amino acid 286 (W286R). Cultured skin fibroblasts of the two patients expressed normal-size VDR protein (immunocytochemistry and Western blotting) and normal length VDR mRNA (Northern blotting). But, these fibroblasts, as well as COS-7 cells transfected with the W286R mutant, failed to bind 3H 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]. The tryptophan substitution did not affect VDR trafficking toward the nucleus but abolished the 24-hydroxylase gene response to 1,25(OH)2D3, even at 10(-6) M concentrations. In conclusion, this case report of a new family with hereditary vitamin D-resistant rickets (HVDRR) emphasizes the crucial role of the VDR tryptophan for ligand binding and for transactivation of 1,25(OH)2D3 target genes. It clearly shows the clinical significance of this VDR amino acid for calcium homeostasis and bone mineralization. This observation suggests further that the presence of a stable VDR-bound ligand may not be obligatory for normal hair follicle development.
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MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- Binding Sites/genetics
- COS Cells
- Calcitriol/pharmacology
- Cells, Cultured
- Child, Preschool
- Cytochrome P-450 Enzyme System/genetics
- DNA, Complementary/genetics
- Female
- Hair Follicle/growth & development
- Humans
- Hypophosphatemia, Familial/genetics
- Infant
- Ligands
- Male
- Mutation, Missense
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptors, Calcitriol/drug effects
- Receptors, Calcitriol/genetics
- Receptors, Calcitriol/metabolism
- Recombinant Proteins/genetics
- Recombinant Proteins/metabolism
- Steroid Hydroxylases/genetics
- Transfection
- Tryptophan/genetics
- Vitamin D3 24-Hydroxylase
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Affiliation(s)
- T M Nguyen
- CNRS-UPR 1524, Hĵpital St. Vincent de Paul, Paris, France
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Abstract
[reaction: see text] A novel reaction between 1,3-dienes and selenium dioxide to give syn 1,2- and 1,4-diol cyclic selenites was studied in detail. This study indicates that an initial concerted [4 + 2] cycloaddition followed by a stereospecific carbon-selenium bond oxidation is involved in this unprecedented syn dihydroxy addition reaction mediated by selenium dioxide.
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Affiliation(s)
- T M Nguyen
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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22
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Lu Y, Nguyen TM, Weltrowska G, Berezowska I, Lemieux C, Chung NN, Schiller PW. [2',6'-Dimethyltyrosine]dynorphin A(1-11)-NH2 analogues lacking an N-terminal amino group: potent and selective kappa opioid antagonists. J Med Chem 2001; 44:3048-53. [PMID: 11543672 DOI: 10.1021/jm0101186] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recent studies showed that dermorphin and enkephalin analogues containing two methyl groups at the 2',6'-positions of the Tyr(1) aromatic ring and lacking an N-terminal amino group were moderately potent delta and mu opioid antagonists. These results indicate that a positively charged N-terminal amino group may be essential for signal transduction but not for receptor binding and suggested that its deletion in agonist opioid peptides containing an N-terminal 2',6'-dimethyltyrosine (Dmt) residue may represent a general way to convert them into antagonists. In an attempt to develop dynorphin A (Dyn A)-derived kappa opioid antagonists, we prepared analogues of [Dmt(1)]Dyn A(1-11)-NH2 (1), in which the N-terminal amino group was either omitted or replaced with a methyl group. This was achieved by replacement of Tyr(1) with 3-(2,6-dimethyl-4-hydroxyphenyl)propanoic acid (Dhp) or (2S)-2-methyl-3-(2,6-dimethyl-4-hydroxyphenyl)propanoic acid [(2S)-Mdp]. Compounds were tested in the guinea pig ileum and mouse vas deferens bioassays and in rat and guinea pig brain membrane receptor binding assays. All analogues turned out to be potent kappa antagonists against Dyn A(1-13) and the non-peptide agonist U50,488 and showed only weak mu and delta antagonist activity. The most potent and most selective kappa antagonist of the series was [(2S)-Mdp(1)]Dyn A(1-11)-NH2 (5, dynantin), which showed subnanomolar kappa antagonist potency against Dyn A(1-13) and very high kappa selectivity both in terms of its K(e) values determined against kappa, mu, and delta agonists and in terms of its ratios of kappa, mu, and delta receptor binding affinity constants. Dynantin is the first potent and selective Dyn A-derived kappa antagonist known and may complement the non-peptide kappa antagonists norbinaltorphimine and GNTI as a pharmacological tool in opioid research.
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Affiliation(s)
- Y Lu
- Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montreal, 110 Pine Avenue West, Montreal, Quebec, H2W 1R7, Canada
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Neilan CL, Nguyen TM, Schiller PW, Pasternak GW. Pharmacological characterization of the dermorphin analog [Dmt(1)]DALDA, a highly potent and selective mu-opioid peptide. Eur J Pharmacol 2001; 419:15-23. [PMID: 11348625 DOI: 10.1016/s0014-2999(01)00946-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dermorphin-derived peptide [Dmt(1)]DALDA (H-Dmt-D-Arg-Phe-Lys-NH(2)), labels mu-opioid receptors with high affinity and selectivity in receptor binding assays. In mouse, radiant heat tail-flick assay [Dmt(1)]DALDA produced profound spinal and supraspinal analgesia, being approximately 5000- and 100-fold more potent than morphine on a molar basis, respectively. When administered systemically, [Dmt(1)]DALDA was over 200-fold more potent than morphine. Pharmacologically, [Dmt(1)]DALDA was distinct from morphine. [Dmt(1)]DALDA displayed no cross-tolerance to morphine in the model used and it retained supraspinal analgesic activity in morphine-insensitive CXBK mice. Supraspinally, it also differed from morphine in its lack of sensitivity towards naloxonazine. Finally, in antisense mapping studies, [Dmt(1)]DALDA was insensitive to MOR-1 exon probes that reduced morphine analgesia, implying a distinct receptor mechanism of action. Thus, [Dmt(1)]DALDA is an interesting and extraordinarily potent, systemically active peptide analgesic, raising the possibility of novel approaches in the design of clinically useful drugs.
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Affiliation(s)
- C L Neilan
- Department of Molecular Neuropharmacology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA
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Heitz A, Hernandez JF, Gagnon J, Hong TT, Pham TT, Nguyen TM, Le-Nguyen D, Chiche L. Solution structure of the squash trypsin inhibitor MCoTI-II. A new family for cyclic knottins. Biochemistry 2001; 40:7973-83. [PMID: 11434766 DOI: 10.1021/bi0106639] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The "knottin" fold is a stable cysteine-rich scaffold, in which one disulfide crosses the macrocycle made by two other disulfides and the connecting backbone segments. This scaffold is found in several protein families with no evolutionary relationships. In the past few years, several homologous peptides from the Rubiaceae and Violaceae families were shown to define a new structural family based on macrocyclic knottin fold. We recently isolated from Momordica cochinchinensis seeds the first known macrocyclic squash trypsin inhibitors. These compounds are the first members of a new family of cyclic knottins. In this paper, we present NMR structural studies of one of them, MCoTI-II, and of a beta-Asp rearranged form, MCoTI-IIb. Both compounds display similar and well-defined conformations. These cyclic squash inhibitors share a similar conformation with noncyclic squash inhibitors such as CPTI-II, and it is postulated that the main effect of the cyclization is a reduced sensitivity to exo-proteases. On the contrary, clear differences were detected with the three-dimensional structures of other known cyclic knottins, i.e., kalata B1 or circulin A. The two-disulfide cystine-stabilized beta-sheet motif [Heitz et al. (1999) Biochemistry 38, 10615-10625] is conserved in the two families, whereas in the C-to-N linker, one disulfide bridge and one loop are differently located. The molecular surface of MCoTI-II is almost entirely charged in contrast to circulin A that displays a well-marked amphiphilic character. These differences might explain why the isolated macrocyclic squash inhibitors from M. cochinchinensis display no significant antibacterial activity, whereas circulins and kalata B1 do.
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Affiliation(s)
- A Heitz
- Centre de Biochimie Structurale, UMR5048 CNRS-Université Montpellier I, UMR554 INSERM-Université Montpellier I, Faculté de pharmacie, 15 avenue Charles Flahault, 34060 Montpellier, France
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Myles TD, Nguyen TM. Relationship between normal amniotic fluid index and birth weight in term patients presenting for labor. J Reprod Med 2001; 46:685-90. [PMID: 11499190] [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] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
OBJECTIVE To investigate whether a relationship between birth weight (BW) and amniotic fluid index (AFI) existed for term patients with intact membranes and, if so, whether it could predict macrosomia and intrauterine growth retardation. STUDY DESIGN Two hundred thirty-one eligible women at term (37-42 weeks' gestation) had an AFI between 5.0 and 24.0 cm at the time of admission. Demographic information was collected, including BW. Statistical comparisons were made, with significance set at P < .05. RESULTS The mean gestational age was 39.5 weeks, and the mean AFI was 11.3. There were 28 infants with BWs > 4,000 g (macrosomia). The cesarean section rate was 16.9%. Macrosomia was associated with a higher cesarean section rate (39.2% vs. 13.8%, P < .002). The mean AFI was higher for those with macrosomia (13.5 vs. 11.0, P < .001). Patients with an AFI > 15.0 had over twice the incidence of macrosomia (RR 2.72, 1.1-6.6, 32.1% vs. 14.8%, P < .027). The risk was even greater for them with an AFI > 18.0 (RR 6.4, 2.2-18.7, P < .002). A linear relationship was observed between AFI and BW (r2 .061, P < .0001). BW increased with increasing AFI. No relationship between AFI of 5-8 and BW < 2,500 g was found. CONCLUSION Increasing AFI correlates linearly with increasing BW, and macrosomia is associated with an increased incidence of cesarean delivery. AFI > 15 carries over double the risk of birth of a macrosomic infant, while AFI > 18 has a risk of over six times. No association between low normal AFI and a growth-restricted infant was found.
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Affiliation(s)
- T D Myles
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Illinois at Chicago, USA.
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26
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Chammas MF, Nguyen TM, Vasavada RA, Nuwayhid BS, Castro LC. Sequential use of Prepidil and extra-amniotic saline infusion for the induction of labor in nulliparous women with very low Bishop scores. J Matern Fetal Med 2001; 10:193-6. [PMID: 11444789 DOI: 10.1080/714904325] [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] [Subscribe] [Scholar Register] [Indexed: 09/30/2022]
Abstract
OBJECTIVE To evaluate the efficacy of sequential use of Prepidil (prostaglandin E2 gel) and extra-amniotic saline infusion for the induction of labor in nulliparous women with very low Bishop scores. STUDY DESIGN Nulliparous women with singleton gestations, intact membranes and a cervical Bishop score of < or = 2 who received Prepidil gel and extra-amniotic saline infusion sequentially for the induction of labor between July 1996 and July 1998 were studied. RESULTS Thirty-one women met the inclusion criteria. Indications for induction included post-dates (six of 31), pre-eclampsia (ten of 31), diabetes (three of 31), oligohydramnios (three of 31), intrauterine growth restriction (two of 31) and non-reactive non-stress test (NST) (seven of 31). The average time from onset of induction to delivery was 38.1 +/- 13.5 h. Vaginal delivery was achieved in 80.6%. Women requiring > 2 doses of Prepidil had a higher risk of delivering abdominally (OR = 3.5). Three of seven (42.9%) women with labor induced for non-reactive NST but only three of 24 (12.5%) with labor induced for other indications had a Cesarean section delivery (p < 0.001). CONCLUSIONS Nulliparous women with very unfavorable cervices can be counselled that they have an 80% chance of vaginal delivery using sequential Prepidil and extra-amniotic saline infusion as an induction method, with 90% delivering within the first 48 h.
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Affiliation(s)
- M F Chammas
- Department of Obstetrics and Gynecology, College of Medicine, University of Illinois at Chicago, 60612, USA
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Young PJ, Le TT, Dunckley M, Nguyen TM, Burghes AH, Morris GE. Nuclear gems and Cajal (coiled) bodies in fetal tissues: nucleolar distribution of the spinal muscular atrophy protein, SMN. Exp Cell Res 2001; 265:252-61. [PMID: 11302690 DOI: 10.1006/excr.2001.5186] [Citation(s) in RCA: 112] [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] [Indexed: 11/22/2022]
Abstract
SMN, the affected protein in spinal muscular atrophy (SMA), is a cytoplasmic protein that also occurs in nuclear structures called "gems" and is involved in snRNP maturation. Coilin-p80 is a marker protein for nuclear Cajal bodies (coiled bodies; CBs) which are also involved in snRNP maturation, storage or transport. We now show that gems and CBs are present in all fetal tissues, even those that lack gems/CBs in the adult. Most gems and CBs occur as separate nuclear structures in fetal tissues, but their colocalization increases with fetal age and is almost complete in the adult. In adult tissues, up to half of all gems/CBs are inside the nucleolus, whereas in cultured cells they are almost exclusively nucleoplasmic. The nucleolar SMN is often more diffusely distributed, compared with nucleoplasmic gems. Up to 30% of cells in fetal tissues have SMN distributed throughout the nucleolus, instead of forming gems in the nucleoplasm. The results suggest a function for gems distinct from Cajal bodies in fetal nuclei and a nucleolar function for SMN. Spinal cord, the affected tissue in SMA, behaves differently in several respects. In both fetal and adult motor neurons, many gems/CBs occur as larger bodies closely associated with the nucleolar perimeter. Uniquely in motor neurons, gems/CBs are more numerous in adult than in fetal stages and colocalization of gems and CBs occurs earlier in development. These unusual features of motor neurons may relate to their special sensitivity to reduced SMN levels in SMA patients.
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Affiliation(s)
- P J Young
- MRIC Biochemistry Group, North East Wales Institute, Mold Road, Wrexham LL11 2AW, United Kingdom
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Lieu C, Nguyen TM, Payant L. In vitro comparison of peak polymerization temperatures of 5 provisional restoration resins. J Can Dent Assoc 2001; 67:36-9. [PMID: 11209503] [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] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
BACKGROUND The heat produced by provisional restoration materials may injure the dental pulp. This study measured and compared peak temperatures during polymerization of 5 materials used in the fabrication of provisional restorations. METHODS The tested materials were 2 self-curing resins (Integrity and Protemp) and 3 dual-cure resins (Iso-Temp, TCB Dual Cure and Provipont DC). A mould the size of a maxillary molar tooth was fabricated to contain 0.5 cc of resin. The temperature rise of the different materials was recorded every 10 seconds over a 10-minute period. RESULTS The rise in temperature of Integrity (peak temperature of 33.8 degrees C) and Protemp Garant (35.6 degrees C) was significantly higher than the rise in temperature of Iso-Temp (29.5 degrees C), TCB Dual Cure (28.4 degrees C) and Provipont DC (29.5 degrees C). CONCLUSION Use of the dual-cure resins in provisional restorations may reduce the risk of pulp injury.
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Affiliation(s)
- C Lieu
- Faculty of Dentistry, Laval University
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29
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Abstract
The tetrapeptide DALDA (H-Tyr-D-Arg-Phe-Lys-NH2) is a polar and selective mu agonist showing poor penetration of the placental and blood-brain barriers. In an effort to enhance the potency of DALDA, analogues containing 2',6'-dimethyltyrosine (Dmt), N,2',6'-trimethyltyrosine (Tmt), 2'-methyltyrosine (Mmt) or 2'-hydroxy,6'-methyltyrosine (Hmt) in place of Tyr1, or Orn or alpha,gamma-diaminobutyric acid (A2bu) in place of Lys4, were synthesized. All compounds displayed high mu receptor selectivity in the rat and guinea pig brain membrane binding assays and most of them were more potent mu agonists than DALDA in the mu receptor-representative guinea pig ileum assay, with [Dmt1]DALDA showing the highest potency. Because of its extraordinary mu agonist potency, high mu selectivity, polar character (charge of 3 + ) and metabolic stability, [Dmt1]DALDA has potential for use in obstetrical or peripheral analgesia.
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Affiliation(s)
- P W Schiller
- Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montreal, Quebec, Canada.
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30
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Chammas MF, Nguyen TM, Li MA, Nuwayhid BS, Castro LC. Expectant management of severe preterm preeclampsia: is intrauterine growth restriction an indication for immediate delivery? Am J Obstet Gynecol 2000; 183:853-8. [PMID: 11035325 DOI: 10.1067/mob.2000.109049] [Citation(s) in RCA: 50] [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: 11/22/2022]
Abstract
OBJECTIVE Expectant management of severe preterm preeclampsia is gaining widespread acceptance in clinical practice. The objective of our study was 2-fold-to determine the frequency of fetal deterioration with expectant management of severe preterm preeclampsia and to evaluate whether the presence of intrauterine growth restriction on admission is associated with a shorter admission-to-delivery interval or more deliveries resulting from nonreassuring fetal status in comparison with pregnancies with preeclampsia but without intrauterine growth restriction. STUDY DESIGN This was an observational study of women with singleton pregnancies at <34 completed weeks' gestation who were admitted to the hospital with the diagnosis of severe preeclampsia and managed expectantly. Fetal status on admission, admission-to-delivery interval, indication for delivery, and neonatal outcome were examined. RESULTS Forty-seven women were studied during a 3-year period (1996-1999). Gestational age at admission was 29.8 +/- 2.6 weeks. The mean admission-to-delivery interval for the entire group was 6.0 +/- 5.1 days; in 42.5% delivery was for fetal indications. In comparison with the absence of intrauterine growth restriction, the presence of intrauterine growth restriction at admission resulted in a significantly shorter admission-to-delivery interval (3.1 +/- 2.1 vs 6.6 +/- 6.1 days; P <.05). Most fetuses with intrauterine growth restriction (85.7%) were delivered before 1 week. Although 57% of fetuses with intrauterine growth restriction were delivered for fetal indications, versus 39% of fetuses without intrauterine growth restriction, these rates were not found to be significantly different. Neonatal outcomes, as reflected by Apgar scores, number of admissions to and duration of stay in the neonatal intensive care unit, and neonatal mortality rates, were similar. CONCLUSION Pregnancies complicated by severe preterm preeclampsia and the presence of intrauterine growth restriction at admission may not benefit from expectant management beyond the 48 hours needed for betamethasone to act. Furthermore, all patients may benefit from close fetal monitoring before delivery because of the high rate of intervention for deteriorating fetal status.
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Affiliation(s)
- M F Chammas
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Illinois at Chicago College of Medicine, Chicago, IL 60612, USA
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Abstract
PURPOSE To describe a digital overlay technique for documenting toric intraocular lens (IOL) axis alignment. SETTING Jules Stein Eye Institute and the Department of Ophthalmology, University of California at Los Angeles School of Medicine, Los Angeles, California, USA. METHODS Digital overlay imaging was used to evaluate the alignment of Staar toric IOLs in 4 eyes of 3 patients who had regular corneal astigmatism at the time of cataract surgery. Lens axes were determined by computerized analysis of digitally scanned retroillumination photographs. A stock digital image of a Staar AA4203TF toric IOL was superimposed on corneal topography images to document IOL alignment with the steep corneal meridian. RESULTS Digital overlay images demonstrated that 3 IOLs in the sample group were within 5 degrees and 1 was within 20 degrees of the intended axis at the time of the final postoperative examination. Slitlamp lens axis estimations were 3 to 18 degrees different from that determined by this technique. CONCLUSION Digital overlay imaging of correctly oriented toric IOLs on computerized corneal topography maps represents an intuitive, accurate, and visually appealing method of documenting toric IOL axis alignment.
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Affiliation(s)
- T M Nguyen
- Jules Stein Eye Institute and the Department of Ophthalmology, University of California at Los Angeles School of Medicine, Los Angeles, California, USA
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Lam LT, Pham YC, Nguyen TM, Morris GE. Characterization of a monoclonal antibody panel shows that the myotonic dystrophy protein kinase, DMPK, is expressed almost exclusively in muscle and heart. Hum Mol Genet 2000; 9:2167-73. [PMID: 10958655 DOI: 10.1093/hmg/9.14.2167] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [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: 11/13/2022] Open
Abstract
Myotonic dystrophy (DM) is a multisystemic disorder caused by an inherited CTG repeat expansion which affects three genes encoding the DM protein kinase (DMPK), a homeobox protein Six5 and a protein containing WD repeats. Using a panel of 16 monoclonal antibodies against several different DMPK epitopes we detected DMPK, as a single protein of approximately 80 kDa, only in skeletal muscle, cardiac muscle and, to a lesser extent, smooth muscle. Many earlier reports of DMPK with different sizes and tissue distributions appear to be due to antibody cross-reactions with more abundant proteins. One such antibody, MANDM1, was used to isolate two related protein kinases, MRCK alpha and beta, from a human brain cDNA library and the shared epitope was located at the catalytic site of DMPK using a phage-displayed random peptide library. The peptide library also identified an epitope shared between DMPK and a 55 kDa muscle-specific protein. The results suggest that effects of the repeat expansion on the DMPK gene may be responsible for muscle and heart features of DM, whereas clinical changes in other tissues may be due to effects on the other two genes.
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Affiliation(s)
- L T Lam
- MRIC Biochemistry Group, PP18, North East Wales Institute, Mold Road, Wrexham LL11 2AW, UK
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Schiller PW, Weltrowska G, Berezowska I, Nguyen TM, Wilkes BC, Lemieux C, Chung NN. The TIPP opioid peptide family: development of delta antagonists, delta agonists, and mixed mu agonist/delta antagonists. Biopolymers 2000; 51:411-25. [PMID: 10797230 DOI: 10.1002/(sici)1097-0282(1999)51:6<411::aid-bip4>3.0.co;2-z] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The discovery of the prototype delta opioid antagonists TIPP (H-Tyr-Tic-Phe-Phe-OH) and TIP (H-Tyr-Tic-Phe-OH) in 1992 was followed by extensive structure-activity relationship studies, leading to the development of analogues that are of interest as pharmacological tools or as potential therapeutic agents. Stable TIPP-derived delta opioid antagonists with subnanomolar delta receptor binding affinity and extraordinary delta receptor selectivity include TIPP[Psi] (H-Tyr-TicPsi[CH(2)NH]Phe-Phe-OH] and TICP[Psi] (H-Tyr-TicPsi[CH(2)NH]Cha-Phe-OH); Cha: cyclohexylalanine), which are widely used in opioid research. Theoretical conformational analyses in conjunction with the pharmacological characterization of conformationally constrained TIPP analogues led to a definitive model of the receptor-bound conformation of H-Tyr-Tic-(Phe-Phe)-OH-related delta opioid antagonists, which is characterized by all-trans peptide bonds. Further structure-activity studies revealed that the delta antagonist vs delta agonist behavior of TIP(P)-derived compounds depended on very subtle structural differences in diverse locations of the molecule and suggested a delta receptor model involving a number of different inactive receptor conformations. A further outcome of these studies was the identification of a new class of potent and very selective dipeptide delta agonists of the general formula H-Tyr-Tic-NH-X (X = arylalkyl), which are of interest for drug development because of their low molecular weight and lipophilic character. Most interestingly, TIPP analogues containing a C-terminal carboxamide group displayed a mixed mu agonist/delta antagonist profile, and thus were expected to be analgesics with a low propensity to produce tolerance and physical dependence. This turned out to be the case with the TIPP-derived mu agonist/delta antagonist DIPP-NH(2)[Psi] (H-Dmt-TicPsi[CH(2)NH]Phe-Phe-NH(2)); Dmt: 2',6'- dimethyltyrosine).
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Affiliation(s)
- P W Schiller
- Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montreal, Quebec, Canada
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34
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Desiderio DM, Wirth U, Lovelace JL, Fridland G, Umstot ES, Nguyen TM, Schiller PW, Szeto HS, Clapp JF. Matrix-assisted laser desorption/ionization mass spectrometric quantification of the mu opioid receptor agonist DAMGO in ovine plasma. J Mass Spectrom 2000; 35:725-733. [PMID: 10862125 DOI: 10.1002/1096-9888(200006)35:6<725::aid-jms1>3.0.co;2-i] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The synthetic opioid peptide analog Tyr-D-Ala-Gly-N-methyl-Phe-Gly-ol (DAMGO), which is a mu opioid receptor-selective agonist, was quantified in ovine plasma samples with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS), using delayed extraction and a reflectron. The internal standard was pentadeuterated DAMGO. Timed-ion selection was used to select the precursor ion. The analysis of the post-source decay fragments improved the detection sensitivity, and the use of the precursor-product ion relationship optimized the specificity. For plasma samples, the inter-assay variability of this method was 6.4% (n = 79) and the intra-assay variability was 6.0% (n = 10). The variability for controls was 3.4% (n = 43). The profile of DAMGO amount versus time was determined in sheep plasma, and the corresponding pharmacokinetic data were calculated.
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MESH Headings
- Analysis of Variance
- Animals
- Enkephalin, Ala(2)-MePhe(4)-Gly(5)-/administration & dosage
- Enkephalin, Ala(2)-MePhe(4)-Gly(5)-/blood
- Enkephalin, Ala(2)-MePhe(4)-Gly(5)-/pharmacokinetics
- Female
- Infusions, Intravenous
- Receptors, Opioid, mu/agonists
- Reference Standards
- Reproducibility of Results
- Sensitivity and Specificity
- Sheep
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/standards
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/statistics & numerical data
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Affiliation(s)
- D M Desiderio
- Charles B. Stout Neuroscience Mass Spectrometry Laboratory, Departments of Neurology and Biochemistry, University of Tennessee, Memphis, 847 Monroe Avenue, Memphis, Tennessee 38163, USA.
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Hernandez JF, Gagnon J, Chiche L, Nguyen TM, Andrieu JP, Heitz A, Trinh Hong T, Pham TT, Le Nguyen D. Squash trypsin inhibitors from Momordica cochinchinensis exhibit an atypical macrocyclic structure. Biochemistry 2000; 39:5722-30. [PMID: 10801322 DOI: 10.1021/bi9929756] [Citation(s) in RCA: 280] [Impact Index Per Article: 11.7] [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: 11/28/2022]
Abstract
Three trypsin inhibitors (TIs), from the seeds of the squash Momordica cochinchinensis (MCo), have been isolated and purified using gel filtration, ion exchange chromatography, and reverse-phase HPLC. Their sequences could be determined only after proteolytic cleavages. In the case of MCoTI-I and -II, it was shown that their polypeptide backbones are cyclic, a structure that has never been described in squash TIs. They contain 34 amino acid residues with 3 disulfide bridges and measured molecular masses of 3453.0 and 3480.7, respectively. They are the largest known macrocyclic peptides containing disulfide bridges. Their sequences show strong homology to other squash TIs, suggesting a similar three-dimensional structure and an analogous mechanism of action. A model of MCoTI-II was constructed by analogy to the crystal structure of the complex between bovine trypsin and CMTI-I, indicating that the linker connecting the two termini is flexible and does not impose significant geometrical constraints. This flexibility allows an Asp-Gly peptide bond rearrangement to occur in this region, giving rise to two isoforms of MCoTI-II. Although the importance of cyclization is not clear, it might confer increased stability and resistance to proteolysis. A minor species, MCoTI-III, was also characterized as containing 30 amino acid residues with a molecular mass of 3379.6. This component possesses a linear backbone with a blocked N-terminus. MCoTIs represent interesting candidates for drug design, either by changing their specificity of inhibition or by using their structure as natural scaffolds bearing new binding activities.
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Affiliation(s)
- J F Hernandez
- Institut de Biologie Structurale Jean-Pierre Ebel (CEA-CNRS), 41, rue Jules Horowitz, 38027 Grenoble Cedex 1, France
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Abstract
This paper focuses on the spectrum of sphenoid sinus lesions that may be seen radiologically and the mapping of disease extent. Imaging plays a central role in the assessment of sphenoid sinus disease. Although primary sphenoid sinus disease is uncommon, this sinus is nevertheless affected secondarily by a variety of pathological processes.
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Affiliation(s)
- V F Chong
- Department of Diagnostic Radiology, Singapore General Hospital, Republic of Singapore.
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Affiliation(s)
- J L Wang
- Division of Surgical Oncology, UCLA Medical Center, Los Angeles, California 90095, USA
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38
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Nguyen TM, Chongsuvivatwong V, Geater A, Prateepchaikul L. Characteristics of repeat aborters in Vietnam. Southeast Asian J Trop Med Public Health 2000; 31:167-72. [PMID: 11023088] [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] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Two hundred and sixty married women seeking induced abortion service in Hanoi, Vietnam were interviewed to determine the magnitude of repeat induced abortion and explore selected characteristics of the repeat aborters. Seventy-one percent of the sample reported having had at least one previous induced abortion. After adjustment for age and number of living children, poor attitudes toward contraception, low use of modern contraceptives and failure of contraception were shown to be significantly associated with repeat induced abortion. Woman's age, number of living children, contraceptive knowledge and experience and desire for no more children were positively related to repeat induced abortion. Socio-demographic characteristics were not related to repeat induced abortion. Improvement of attitudes toward contraception, persuasion to use modern contraception and promotion of contraceptive effectiveness are recommended strategies to prevent repeat induced abortion.
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Affiliation(s)
- T M Nguyen
- Scientific Research Department, Institute for the Protection of the Mother and Newborn, Hanoi, Vietnam.
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Schiller PW, Berezowska I, Nguyen TM, Schmidt R, Lemieux C, Chung NN, Falcone-Hindley ML, Yao W, Liu J, Iwama S, Smith AB, Hirschmann R. Novel ligands lacking a positive charge for the delta- and mu-opioid receptors. J Med Chem 2000; 43:551-9. [PMID: 10691681 DOI: 10.1021/jm990461z] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recently we reported using minilibraries to replace Lys(9) [somatostatin (SRIF) numbering] of the potent somatostatin agonist L-363,301 (c[-Pro-Phe-D-Trp-Lys-Thr-Phe-]) to generate the potent neurokinin receptor (NK-1) antagonist c[-Pro-Phe-D-Trp-p-F-Phe-Thr-Phe-]. This novel cyclic hexapeptide did not bind the SRIF receptor. Thus, a single mutation converted L-363,301, a SRIF agonist with potency ca. 2-8 times the potency of SRIF in laboratory animals,(24) into a selective NK-1 receptor antagonist with an IC(50) of 2 nM in vitro. During the screening of the same libraries for ligands of the delta-opioid receptor, we identified four compounds (1-4) which represent a new class of delta-opioid antagonists, some of which were also NK-1 receptor antagonists. The most potent delta-opioid antagonist, c[-Pro-1-Nal-D-Trp-Tyr-Thr-Phe-] (2), showed a K(e) value of 128 nM in the mouse vas deferens assay and a delta-receptor binding affinity constant of 152 nM in the rat brain membrane binding assay. These results are of interest because they represent a novel class of delta-opioid antagonists and, like two previously reported delta-opioid antagonists, they lack a positive charge. To examine further the requirement for a positive charge in the delta-opioid ligands, we prepared two analogues of the beta-casomorphin-derived mixed mu-agonist/delta-antagonist, H-Dmt-c[-D-Orn-2-Nal-D-Pro-Gly-] (7), in which we eliminated the positive charge either through formylation of the primary amino group (5) or by the deletion of this N-terminal amino group (6). These latter compounds proved to be delta-opioid antagonists with K(e) values in the 16-120 nM range, as well as fairly potent mu-opioid antagonists (K(e) approximately 200 nM). These six compounds provide the most convincing evidence to date that there is no requirement for a positive charge in mu- and delta-opioid receptor antagonists. In addition, cyclic hexapeptide 4 lacks a phenolic hydroxyl group. Taken together, these data suggest that the prevailing assumptions about delta- and mu-opioid receptor binding need revision and that the receptors for these opioid ligands have much in common with the NK-1 and somatostatin receptors.
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MESH Headings
- Animals
- Binding, Competitive
- Brain/metabolism
- Guinea Pigs
- Ileum/drug effects
- In Vitro Techniques
- Ligands
- Male
- Mice
- Muscle Contraction/drug effects
- Muscle, Smooth/drug effects
- Narcotic Antagonists/chemical synthesis
- Narcotic Antagonists/chemistry
- Narcotic Antagonists/pharmacology
- Neurokinin-1 Receptor Antagonists
- Oligopeptides/chemical synthesis
- Oligopeptides/chemistry
- Oligopeptides/metabolism
- Oligopeptides/pharmacology
- Peptides, Cyclic/chemical synthesis
- Peptides, Cyclic/chemistry
- Peptides, Cyclic/metabolism
- Peptides, Cyclic/pharmacology
- Radioligand Assay
- Rats
- Receptors, Neurokinin-1/metabolism
- Receptors, Opioid, mu/antagonists & inhibitors
- Receptors, Opioid, mu/metabolism
- Structure-Activity Relationship
- Vas Deferens/drug effects
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Affiliation(s)
- P W Schiller
- Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montréal, 110 Pine Avenue West, Montréal, Quebec, Canada
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Abstract
OBJECTIVE To summarize published data on the comparative efficacy of sorbitol and xylitol for prevention of dental caries. DATA SOURCES Published double-blind comparative trials, using sorbitol and xylitol products, identified by MEDLINE (January 1966-December 1998) and International Pharmaceutical Abstracts (January 1970-December 1998) searches. DATA SYNTHESIS Clinical trials generally used sorbitol and xylitol gums, which patients chewed three to five times daily for 20-40 months. Xylitol was superior to sorbitol in two longer, secondary dentition trials (30-63% reductions), but not in two primary dentition trials. CONCLUSIONS The data suggest that xylitol-containing gums may provide superior efficacy in reducing caries rates in high-risk populations.
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Affiliation(s)
- M A Gales
- Department of Pharmacy Practice, School of Pharmacy, Southwestern Oklahoma State University, Weatherford, USA
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41
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Schiller PW, Fundytus ME, Merovitz L, Weltrowska G, Nguyen TM, Lemieux C, Chung NN, Coderre TJ. The opioid mu agonist/delta antagonist DIPP-NH(2)[Psi] produces a potent analgesic effect, no physical dependence, and less tolerance than morphine in rats. J Med Chem 1999; 42:3520-6. [PMID: 10479285 DOI: 10.1021/jm980724+] [Citation(s) in RCA: 148] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Opioid compounds with mixed mu agonist/delta antagonist properties are expected to be analgesics with low propensity to produce tolerance and dependence. In an effort to strengthen the mu agonist component of the mixed mu agonist/delta antagonist H-Tyr-Tic-Phe-Phe-NH(2) (TIPP-NH(2)), analogues containing structurally modified tyrosine residues in place of Tyr(1) were synthesized. Among the prepared compounds, H-Dmt-Tic-Phe-Phe-NH(2) (DIPP-NH(2); Dmt = 2',6'-dimethyltyrosine) and H-Dmt-TicPsi[CH(2)NH]Phe-Phe-NH(2) (DIPP-NH(2)[Psi]) retained a mixed mu agonist/delta antagonist profile, as determined in the guinea pig ileum and mouse vas deferens assays, whereas H-Tmt-Tic-Phe-Phe-NH(2) (Tmt = N,2',6'-trimethyltyrosine) was a partial mu agonist/delta antagonist and H-Tmt-TicPsi[CH(2)NH]Phe-Phe-NH(2) was a mu antagonist/delta antagonist. DIPP-NH(2)[Psi] showed binding affinities in the subnanomolar range for both mu and delta receptors in the rat brain membrane binding assays, thus representing the first example of a balanced mu agonist/delta antagonist with high potency. In the rat tail flick test, DIPP-NH(2)[Psi] given icv produced a potent analgesic effect (ED(50) = 0.04 microg), being about 3 times more potent than morphine (ED(50) = 0.11 microg). It produced less acute tolerance than morphine but still a certain level of chronic tolerance. Unlike morphine, DIPP-NH(2)[Psi] produced no physical dependence whatsoever upon chronic administration at high doses (up to 4.5 microg/h) over a 7-day period. In conclusion, DIPP-NH(2)[Psi] fulfills to a large extent the expectations based on the mixed mu agonist/delta antagonist concept with regard to analgesic activity and the development of tolerance and dependence.
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Affiliation(s)
- P W Schiller
- Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montreal, 110 Pine Avenue West, Montreal, Quebec, Canada H2W 1R7
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Garabédian M, Menn S, Nguyen TM, Ruiz JC, Callens A, Uhlrich J. [Prevention of vitamin D deficiency in the child and adolescent. I. Proposal and arguments for use of a decision tree]. Arch Pediatr 1999; 6:990-1000. [PMID: 10519036 DOI: 10.1016/s0929-693x(99)80595-8] [Citation(s) in RCA: 15] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
A decision-making table, using three questionnaires, is proposed to determine the vitamin D status in children and adolescents. The first questionnaire assesses the vitamin D endogenous synthesis, taking into account the sunlight exposure and the time interval out of the sun. The second questionnaire quantifies the vitamin D dietary intake within three levels: optimal, medium or low. In case of a medium dietary score, a third questionnaire evaluates the daily calcium intake, taking into account the fact that vitamin D metabolism is increased by a low calcium intake (under 400 mg/day). This decision-making table should enable the detection of children and adolescents at risk of vitamin D deficiency and requiring an adapted prophylaxis. Its accuracy will be assessed in prospective surveys.
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Affiliation(s)
- M Garabédian
- Unité CNRS UPR 1524, hôpital Saint-Vincent-de-Paul, Paris, France
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Garabedian M, Nguyen TM. [Disorders of the vitamin D nuclear receptor: from children to transgenic mice]. Ann Endocrinol (Paris) 1999; 60:251-2. [PMID: 10520419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Affiliation(s)
- M Garabedian
- CNRS UPR 1524, Hôpital Saint-Vincent-de-Paul, Paris
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Wilkinson FL, Nguyen TM, Manilal SB, Thomas P, Neal JW, Harper PS, Jones AL, Morris GE. Localization of rabbit huntingtin using a new panel of monoclonal antibodies. Brain Res Mol Brain Res 1999; 69:10-20. [PMID: 10350633 DOI: 10.1016/s0169-328x(99)00097-2] [Citation(s) in RCA: 20] [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] [Indexed: 11/25/2022]
Abstract
Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by the expansion of a CAG repeat which is expressed as a polyglutamine tract near the N-terminus of the gene product, huntingtin. N-terminal huntingtin fragments form intranuclear aggregates in HD patients and these may be involved in the pathogenesis. Monoclonal antibodies (mAbs) against three different regions of huntingtin (amino acids 997-1276, 1844-2131 and 2703-2911) have been produced and two of the epitopes have been identified using phage displayed peptide libraries. All mAbs reacted with 350 kDa huntingtin on Western blots and one mAb from each region was selected for further study by strong immunoreactivity with neurons in different regions of rabbit brain and by ability to immunoprecipitate native huntingtin. Subcellular fractionation and sucrose density centrifugation of rabbit brain extract showed that most of the huntingtin exists as a high molecular weight complex in the cytoplasm. Two outstanding problems have been addressed; the location of huntingtin in tissues outside the central nervous system and whether huntingtin is present in the nucleus of normal cells. We conclude that huntingtin is present at low levels in most non-neuronal cells though we have identified an interstitial cell type in skin with very high immunoreactivity. Using both immunolocalization and nuclear purification methods, we were unable to exclude the possibility that a small proportion of full-length huntingtin is present in the nucleus.
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Affiliation(s)
- F L Wilkinson
- MRIC Biochemistry Group, NE Wales Institute, Plas Coch, Wrexham, LL11 2AW, UK
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Abstract
Lateral ankle sprains are the most frequently encountered injuries in sports. In the evaluation of lateral ankle injury, one should consider all soft tissue structures (i.e., peroneal tendons, ligaments of the ankle, subtalar joints, around the lateral ankle). The treatment of most ankle sprains has evolved from immobilization to functional rehabilitation. Many patients with ankle sprains return to their previous activities. A few patients are left with pain and residual instability after conservative treatment; thus, the question of when to operate on acute severe ankle sprain remains controversial. The other challenge physicians face is the problem of persistent lateral ankle pain after sprain. This condition may be due to intra-articular or extra-articular pathology (i.e., soft tissue lateral ankle impingement, osteochondral lesion, or partial peroneal tendon tear). Diagnosis can be made with careful history, physical examination, and appropriate ancillary studies. Only proper diagnosis can lead to uncompromised, undelayed patient care.
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Affiliation(s)
- S H Liu
- UCLA Medical Center 90095, USA
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Schiller PW, Weltrowska G, Schmidt R, Berezowska I, Nguyen TM, Lemieux C, Chung NN, Carpenter KA, Wilkes BC. Subtleties of structure-agonist versus antagonist relationships of opioid peptides and peptidomimetics. J Recept Signal Transduct Res 1999; 19:573-88. [PMID: 10071786 DOI: 10.3109/10799899909036673] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The development of novel delta opioid antagonists and delta opioid agonists structurally derived from the prototype delta antagonist TIPP (H-Tyr-Tic-Phe-Phe-OH), is reviewed. Both delta antagonists and delta agonists with extraordinary potency and unprecedented delta receptor selectivity were discovered. Some of them are already widely used as pharmacological tools and are also of interest as potential therapeutic agents for use in analgesia. The results of the performed structure-activity studies revealed that the delta antagonist versus delta agonist behavior of this class of compounds depended on very subtle structural differences in diverse locations of the molecule. These observations can be best explained with a receptor model involving a number of different inactive and active receptor conformations.
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Affiliation(s)
- P W Schiller
- Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montreal, Que., Canada
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Morris GE, Nguyen TM, Nguyen TN, Pereboev A, Kendrick-Jones J, Winder SJ. Disruption of the utrophin-actin interaction by monoclonal antibodies and prediction of an actin-binding surface of utrophin. Biochem J 1999; 337 ( Pt 1):119-23. [PMID: 9854033 PMCID: PMC1219944] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Monoclonal antibody (mAb) binding sites in the N-terminal actin-binding domain of utrophin have been identified using phage-displayed peptide libraries, and the mAbs have been used to probe functional regions of utrophin involved in actin binding. mAbs were characterized for their ability to interact with the utrophin actin-binding domain and to affect actin binding to utrophin in sedimentation assays. One of these antibodies was able to inhibit utrophin-F-actin binding and was shown to recognize a predicted helical region at residues 13-22 of utrophin, close to a previously predicted actin-binding site. Two other mAbs which did not affect actin binding recognized predicted loops in the second calponin homology domain of the utrophin actin-binding domain. Using the known three-dimensional structure of the homologous actin-binding domain of fimbrin, these results have enabled us to determine the likely orientation of the utrophin actin-binding domain with respect to the actin filament.
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Affiliation(s)
- G E Morris
- MRIC Biochemistry Group, N.E. Wales Institute, Mold Road, Wrexham LL1 2AW, Wales, U.K
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48
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Abstract
Emerin is a nuclear membrane protein which is affected by mutation in X-linked Emery-Dreifuss muscular dystrophy. We have previously suggested that emerin is a member of a family of type II integral membrane proteins which associate with the nuclear lamina and which include lamina-associated proteins and the lamin B receptor. We now show that emerin in COS cells is not restricted to the nuclear rim but is also found at intranuclear sites, where it colocalizes with nuclear lamins B1, B2 and A/C. During mitosis, emerin is dispersed throughout the cell and then participates in the reconstitution of membranes around the daughter nuclei. Although emerin and lamins do not remain colocalized during mitosis, they all show some association with the midbody of the mitotic spindle.
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Affiliation(s)
- S Manilal
- MRIC Biochemistry Group, N.E. Wales Institute, Wrexham, United Kingdom
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Pei Y, Barber LA, Murphy RC, Johnson CA, Kelley SW, Dy LC, Fertel RH, Nguyen TM, Williams DA, Travers JB. Activation of the epidermal platelet-activating factor receptor results in cytokine and cyclooxygenase-2 biosynthesis. J Immunol 1998; 161:1954-61. [PMID: 9712066] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Recent studies suggest that the lipid mediator platelet-activating factor (PAF) is involved in keratinocyte function and skin inflammation. Indeed, PAF is found in association with inflammatory skin diseases, intradermal injections of PAF induce inflammation, and keratinocytes express functional PAF receptors (PAF-R). One mechanism by which the keratinocyte PAF-R could contribute to epidermal functions and inflammatory states would be through the synthesis of inflammatory regulators, such as PAF, PGs, and cytokines. The ability of the epidermal PAF-R to induce the synthesis of these immunomodulators was tested using a model system created by transduction of the PAF-R-negative human epidermal cell line KB with the PAF-R. Activation of this epidermal PAF-R resulted in arachidonic acid release, and the biosynthesis of PAF and PGE2. In addition, the KB PAF-R triggered increased levels of mRNA and protein for the inducible isozyme of cyclooxygenase (COX-2) as well as IL-6 and IL-8, both of which have been implicated in skin inflammatory processes. Studies with the human keratinocyte-derived epidermal cell line HaCaT revealed that activation of the endogenous PAF-R led to the increased accumulation of COX-2, IL-6, and IL-8 mRNA similar to that seen with the KB PAF-R model system. Finally, treatment of HaCaT keratinocytes with IL-8 resulted in PAF biosynthesis, indicating the existence of a positive feedback loop between IL-8 and PAF in epidermal cells. These studies suggest involvement of PAF and the PAF-R in the epidermal cytokine network.
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Affiliation(s)
- Y Pei
- Department of Dermatology, Indiana University School of Medicine, Indianapolis 46202, USA
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50
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Thomas P, Wilkinson F, Nguyen TM, Harper PS, Neal JW, Morris GE, Jones AL. Full length huntingtin is not detected in intranuclear inclusions in Huntington's disease brain. Biochem Soc Trans 1998; 26:S243. [PMID: 9765962 DOI: 10.1042/bst026s243] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- P Thomas
- Institute of Medical Genetics, University of Wales College of Medicine, Cardiff, UK
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