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Early regression index (ERI) on MR images as response predictor in esophageal cancer treated with neoadjuvant chemo-radiotherapy: Interim analysis of the prospective ESCAPE trial. Radiother Oncol 2024; 194:110160. [PMID: 38369025 DOI: 10.1016/j.radonc.2024.110160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 02/05/2024] [Accepted: 02/13/2024] [Indexed: 02/20/2024]
Abstract
PURPOSE The early regression index (ERI) predicts treatment response in rectal cancer patients. Aim of current study was to prospectively assess tumor response to neoadjuvant chemo-radiotherapy (nCRT) of locally advanced esophageal cancer using ERI, based on MRI. MATERIAL AND METHODS From January 2020 to May 2023, 30 patients with esophageal cancer were enrolled in a prospective study (ESCAPE). PET-MRI was performed: i) before nCRT (tpre); ii) at mid-radiotherapy, tmid; iii) after nCRT, 2-6 weeks before surgery (tpost); nCRT delivered 41.4 Gy/23fr with concurrent carboplatin and paclitaxel. For patients that skipped surgery, complete clinical response (cCR) was assessed if patients showed no local relapse after 18 months; patients with pathological complete response (pCR) or with cCR were considered as complete responders (pCR + cCR). GTV volumes were delineated by two observers (Vpre, Vmid, Vpost) on T2w MRI: ERI and other volume regression parameters at tmid and tpost were tested as predictors of pCR + cCR. RESULTS Complete data of 25 patients were available at the time of the analysis: 3/25 with complete response at imaging refused surgery and 2/3 were cCR; in total, 10/25 patients showed pCR + cCR (pCR = 8/22). Both ERImid and ERIpost classified pCR + cCR patients, with ERImid showing better performance (AUC:0.78, p = 0.014): A two-variable logistic model combining ERImid and Vpre improved performances (AUC:0.93, p < 0.0001). Inter-observer variability in contouring GTV did not affect the results. CONCLUSIONS Despite the limited numbers, interim analysis of ESCAPE study suggests ERI as a potential predictor of complete response after nCRT for esophageal cancer. Further validation on larger populations is warranted.
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Anticoagulation and Antiplatelet Therapy for Prevention of Venous and Arterial Thrombotic Events in Critically Ill Patients With COVID-19: COVID-PACT. Circulation 2022; 146:1344-1356. [PMID: 36036760 PMCID: PMC9624238 DOI: 10.1161/circulationaha.122.061533] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
BACKGROUND The efficacy and safety of prophylactic full-dose anticoagulation and antiplatelet therapy in critically ill COVID-19 patients remain uncertain. METHODS COVID-PACT (Prevention of Arteriovenous Thrombotic Events in Critically-ill COVID-19 Patients Trial) was a multicenter, 2×2 factorial, open-label, randomized-controlled trial with blinded end point adjudication in intensive care unit-level patients with COVID-19. Patients were randomly assigned to a strategy of full-dose anticoagulation or standard-dose prophylactic anticoagulation. Absent an indication for antiplatelet therapy, patients were additionally randomly assigned to either clopidogrel or no antiplatelet therapy. The primary efficacy outcome was the hierarchical composite of death attributable to venous or arterial thrombosis, pulmonary embolism, clinically evident deep venous thrombosis, type 1 myocardial infarction, ischemic stroke, systemic embolic event or acute limb ischemia, or clinically silent deep venous thrombosis, through hospital discharge or 28 days. The primary efficacy analyses included an unmatched win ratio and time-to-first event analysis while patients were on treatment. The primary safety outcome was fatal or life-threatening bleeding. The secondary safety outcome was moderate to severe bleeding. Recruitment was stopped early in March 2022 (≈50% planned recruitment) because of waning intensive care unit-level COVID-19 rates. RESULTS At 34 centers in the United States, 390 patients were randomly assigned between anticoagulation strategies and 292 between antiplatelet strategies (382 and 290 in the on-treatment analyses). At randomization, 99% of patients required advanced respiratory therapy, including 15% requiring invasive mechanical ventilation; 40% required invasive ventilation during hospitalization. Comparing anticoagulation strategies, a greater proportion of wins occurred with full-dose anticoagulation (12.3%) versus standard-dose prophylactic anticoagulation (6.4%; win ratio, 1.95 [95% CI, 1.08-3.55]; P=0.028). Results were consistent in time-to-event analysis for the primary efficacy end point (full-dose versus standard-dose incidence 19/191 [9.9%] versus 29/191 [15.2%]; hazard ratio, 0.56 [95% CI, 0.32-0.99]; P=0.046). The primary safety end point occurred in 4 (2.1%) on full dose and in 1 (0.5%) on standard dose (P=0.19); the secondary safety end point occurred in 15 (7.9%) versus 1 (0.5%; P=0.002). There was no difference in all-cause mortality (hazard ratio, 0.91 [95% CI, 0.56-1.48]; P=0.70). There were no differences in the primary efficacy or safety end points with clopidogrel versus no antiplatelet therapy. CONCLUSIONS In critically ill patients with COVID-19, full-dose anticoagulation, but not clopidogrel, reduced thrombotic complications with an increase in bleeding, driven primarily by transfusions in hemodynamically stable patients, and no apparent excess in mortality. REGISTRATION URL: https://www. CLINICALTRIALS gov; Unique identifier: NCT04409834.
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An interdisciplinary intervention for health prevention and promotion in a Roman neighborhood. Eur J Public Health 2022. [PMCID: PMC9620524 DOI: 10.1093/eurpub/ckac130.139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Influencing behavioral patterns through primary prevention, possibly addressing more risk factors at a time, is the most effective means to tackle cardiovascular diseases. Many interdisciplinary prevention activities have been coordinated by community nurses outside of specialist centers, resulting in a more effective control of risk factors. Our study aims at describing the impact of an 18-month prevention and promotion, interdisciplinary intervention on lifestyle habits and cardiovascular risk. From December 2018 to May 2020, patients were recruited by 4 General Practitioners (GPs) in the Roman neighborhood of Torresina and received nutritional, physical and psychological counselling to learn healthy lifestyles. Until May 2020 patients had to self-manage their new healthy habits, but during this phase the SARS-CoV-2 pandemic broke out. Patients were assessed at baseline, 6, 12 and 18 months by a nutritionist, a physiotherapist, a psychologist, the 4 GPs and community nurses, and the cardiovascular risk score (CRS) was estimated at every examination. 76 patients were included, with a mean age of 54,6 years. Mean CRS showed a significant reduction between baseline and 12 months (from 4.9 to 3.8, p < 0.001), but this trend was not maintained at 18 months. As for variables included in the calculation of the cardiovascular risk score, both total cholesterol and systolic blood pressure significantly decreased at 6 months of follow up (respectively, from 211.1 to 192 (p < 0.001) and from 133.1 to 123.1(p < 0.001)). Nontheless, the reduction was maintained in the remaining points in time only for systolic blood pressure. Our interdisciplinary educational intervention in a primary care setting resulted in a CRS improvement at 12 months, but this changes where not maintained at 18 months. Community nurses were facilitators in improving health outcomes and patient's satisfaction in the described primary care setting. Key messages
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White matter integrity and pro-inflammatory cytokines as predictors of antidepressant response in MDD. Eur Psychiatry 2022. [PMCID: PMC9567974 DOI: 10.1192/j.eurpsy.2022.1415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Introduction Major depressive disorder (MDD) often involves immune dysregulation with high peripheral levels of pro-inflammatory cytokines that might have an impact on the clinical course and treatment response. Moreover, MDD patients show brain volume changes and white matter (WM) alterations that are already existing in the early stage of illness. Objectives The aim of the present review is to elucidate the association between inflammation and WM integrity and its impact on the pathophysiology and progression of MDD as well as the role of possible novel biomarkers of treatment response to improve MDD prevention and treatment strategies. Methods We conducted an electronic literature search of PubMed on studies that examined the role of inflammation in depression and that focused on WM integrity and pro-inflammatory cytokines as predictors of antidepressant response. Results There is evidence for central effects of peripheral inflammation which could activate microglia which, in turn, might trigger a cascade of inflammatory processes leading to neurotransmitter imbalances. Numerous studies indicated that both altered levels of peripheral inflammatory markers, particularly TNF-α, IL-6, and CRP as well as WM integrity might predict antidepressant treatment outcome. Conclusions Despite mounting evidence on the impact of the immune system on WM microstructure, no study has yet addressed the interaction between the two factors in influencing antidepressant response. There is a lack of reproducible biomarkers predicting treatment response on an individual basis. The availability of such biomarkers would enable more efficient and personalized treatments with a faster treatment response and better prevention of treatment resistance. Disclosure No significant relationships.
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Coping Styles in the SARS-CoV-2 national lockdown: impact on behaviors for cardiovascular prevention. Eur J Public Health 2021. [DOI: 10.1093/eurpub/ckab165.418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
Coping styles are the ways in which people deal with different stressor situations. Coping strategies can be categorized into three types: task-oriented, emotion-oriented, and avoidance-oriented. Several studies showed a strong relationship between coping styles and cardiovascular diseases. The aim of the study was to evaluate how much the SARS-CoV-2 national lockdown has impacted the coping strategies on behaviors for cardiovascular prevention.
Methods
62 participants from Rome were recruited to assess the impact of prevention and promotion of health on Individual Cardiovascular Risk. The Coping Inventory to Stressful Situations (CISS, Endler & Parker, 1990) is a self-report questionnaire that measures the three strategies of coping. Behaviors dealing with cardiovascular prevention were evaluated at the beginning of the observation period, and after 6, 12, and 18 months. During 12 (February 2020) and 18 months (July 2020) the SARS-CoV-2 national lockdown enabled us to inquire into coping strategies in stressful situations and cardiovascular risk factors.
Results
The Pearson correlation analysis was used to assess the existence of a correlation between coping strategies and the variation of cardiovascular risk factors and alcohol consumption at 12 and 18 months. Interestingly, results showed relations between Emotional-oriented (r = 0.26 p < 0.05) and Task-oriented (r = -0.33 p < 0.01) coping styles and Differential Cardiovascular Risk Reduction (DCRR). Furthermore, a positive relation between Task-oriented (r = 0.34 p < 0.01) coping style and Differential Alcohol Consumption (DAC) was observed.
Conclusions
We found that the DCRR relates to the Emotional- and Task-oriented coping styles, while DAC is associated with the Task-oriented coping style. The strength of our study consists in the territorial and multidisciplinary dimension of the project, the main critical issue is represented by the small size of the patient sample.
Key messages
A relationship can be described between Differential Cardiovascular Risk Reduction and Emotional- and Task-oriented coping styles. There is a relationship between Differential Alcohol Consumption and the Task-oriented coping style.
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Efficacy and safety of a novel hydrogel (HYADD4-G) in degenerative disc disease patients: a multicentric open label study. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2021; 24:2692-2703. [PMID: 32196620 DOI: 10.26355/eurrev_202003_20539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVE In this premarket clinical study, we evaluated the efficacy and safety of a novel Hydrogel (HYADD4-G) for reducing low back pain (LBP) in patients with degenerative disc disease (DDD). PATIENTS AND METHODS Twenty-three patients with chronic LBP were enrolled. All patients presented with up to three lumbar black discs (Pfirrmann grade III or IV), LBP of at least 40 mm on the Visual Analogue Scale (VAS), and a Roland-Morris Disability Questionnaire (RMDQ) score of at least 9. Patients received a single 1.5 ml intradiscal injection of HYADD4-G (8 mg/ml), guided by X-ray. Our primary endpoint was the change in VAS score from baseline (day 0) to 4, 12, and 24 weeks. Our secondary endpoints were black disc hydration by Magnetic Resonance Imaging (MRI); the patient's therapeutic response according to the RMDQ; the quality of life, as determined by the EuroQol-5 Dimension (EQ-5D) Index; and a global assessment of patient health status, safety, and local tolerability. RESULTS Compared with baseline values, VAS score showed a significant reduction at each time point, and across the overall 24-week follow-up period (p < 0.0001). MRI scanning observed a significant reduction in Pfirrmann grade from baseline, by at least one grade, at both week 4 (p = 0.0039) and week 24 (p = 0.0010). Furthermore, compared with baseline values, there was a significant reduction in RMDQ score at each timepoint, and across the entire study period (p < 0.0001). The EQ-5D index increased significantly from baseline to week 24 (p = 0.0001). Finally, mean VAS scores for Patient Global Assessment (PTGA), and Clinical Observer Global Assessment (COGA), decreased significantly at each time point (p < 0.0001), except for week 4. CONCLUSIONS HYADD4-G proved to be an efficient reliever of low back pain due to DDD.
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Clinical and diagnostic findings in COVID-19 patients: an original research from SG Moscati Hospital in Taranto Italy. J BIOL REG HOMEOS AG 2021; 35:171-183. [PMID: 33491346 DOI: 10.23812/20-605-a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The coronavirus disease 2019 (COVID-19) pandemic is a worldwide medical challenge due to the scarcity of proper information and remedial resources. The ability to efficiently avoid a further SARS-CoV-2 pandemic will, therefore, depend on understanding several factors which include host immunity, virus behavior, prevention measures, and new therapies. This is a multi-phase observatory study conducted in the SG Moscati Hospital of Taranto in Italy that was converted into COVID-19 Special Care Unit for SARS-Co-V2 risk management. Patients were admitted to the 118 Emergency Pre-Hospital and Emergency Department based on two diagnostic criteria, the nasopharyngeal swab assessed by reverse-transcriptase-polymerase-chain-reaction (RT-PCR) and CT-scan image characterized by ground glass opacity. Patients were divided into four groups, positive-positive (ER-PP), negative-positive (ER-NP), negative-negative (ER-NN) and a group admitted to the ICU (ER-IC). A further control group was added when the T and B lymphocyte subsets were analyzed. Data included gender, age, vital signs, arterial blood gas analysis (ABG), extensive laboratory results with microbiology and bronchoalveolar lavage fluid (BALF) which were analyzed and compared. Fundamental differences were reported among the groups. Males were significantly higher in PP, ICU, and NP groups, from 2 to 4-fold higher than females, while in the NN group, the number of females was mildly higher than males; the PP patients showed a marked alkalotic, hypoxic, hypocapnia ABG profile with hyperventilation at the time of admission; finally, the laboratory and microbiology results showed lymphopenia, fibrinogen, ESR, CRP, and eGFR were markedly anomalous. The total number of CD4+ and CD8+ T cells was dramatically reduced in COVID-19 patients with levels lower than the normal range delimited by 400/μL and 800/μL, respectively, and were negatively correlated with blood inflammatory responses.
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Abstract
The World elderly population is expected to double before 2050. Unhealthy habits and unhealthy lifestyles are commonly associated with age-related diseases or their worsening. Modification in daily lifestyle and diet may help preventing age-related diseases onset and efficiently affecting their evolution, thus promoting the Healthy Aging process, concept recently coined to describe the disease-free aging process. This review highlights the role of nutrition science in promoting healthy aging. Since the Mediterranean Model demonstrated to be a useful style in supporting healthy aging, promotion of this correct lifestyle by health policies seems to be the best approach to achieve this target.
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How cosmetic tightening products modulate the biomechanics and morphology of human skin. Acta Biomater 2020; 115:299-316. [PMID: 32853810 DOI: 10.1016/j.actbio.2020.08.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 08/18/2020] [Accepted: 08/18/2020] [Indexed: 12/26/2022]
Abstract
The active and passive mechanical behavior of a cosmetic tightening product for skin anti-aging is investigated based on a wide range of in vivo and in vitro measurements. The experimental data are used to inform a numerical model of the attained cosmetic effect, which is then implemented in a commercial finite-element framework and used to analyze the mechanisms that regulate the biomechanical interaction between the native tissue and the tightening film. Such a film reduces wrinkles and enhances skin consistency by increasing its stiffness by 48-107% and reducing inelastic, non-recoverable deformations (-47%). The substrate deformability influences both the extent of tightening and the reduction of wrinkle amplitude. The present findings allow, for the first time, to rationalize the mechanisms of action of cosmetic products with a tightening action and provide quantitative evidence for further optimization of this fascinating class of biomaterials.
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Multidisciplinary community approach to reduce cardiovascular risk factors in a neighborhood in Rome. Eur J Public Health 2020. [DOI: 10.1093/eurpub/ckaa165.446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Cardiovascular Diseases (CVDs) are one of the main causes of death and morbidity worldwide. To reduce the risk of occurrence it is necessary to promote a healthy lifestyle and consider health as a collective benefit. This study aims to evaluate how the implementation of preventive interventions and health promotion could reduce the impact of CVDs on the involved population.
This prospective study started 1 year ago and will last 18 months (July 2020). Participants have been recruited in General Practice clinic in Torresina neighbourhood in Rome. The intervention was a full year of multidisciplinary meetings scheduled with general practitioners, community nurses, dedicated professionals (nutritionist, physiotherapist, psychologist) and outdoor events with a coach to promote group physical activity, assisted by the use of social networks. Anthropometric data, blood chemistry tests and information about lifestyle, nutritional habits and physical activity were collected at time 0 and every 2-month follow-up and, additionally, the individual cardiovascular risk score (CVRS) was calculated. After 12 and up to 18 months, instead, the self-management ability of a correct lifestyle will be evaluated on the basis of the measured outcomes. Statistical analysis was performed using a paired t test with Jamovi software.
The sample size was 62 patients, 50% male with an average age of 54.6 years (±7.8). During the analyzed period there was a reduction in the percentage of smokers from 30.6% at baseline to 22.6% after 12 months. The baseline CVRS was 4.9% (±6.3). At 12 months the CVRS significantly decreased to 3.8% (±4.0) (p < 0.01). Total cholesterol level was 211.1 mg/dl (±32.8) at baseline, with a significant reduction at 12 months (202.5 ± 37.8) (p = 0.01). The results are preliminary.
Multidisciplinary interventions resulted in a significant reduction of CVRS and cholesterol levels during the study period. Further studies are necessary to evaluate our approach.
Key messages
Cardiovascular Diseases are the main causes of deaths among the population, so primary prevention through tailored educational interventions is fundamental. A multidisciplinary approach has proven to be effective in reducing the risk of cardiovascular disease and the level of cholesterol.
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Metastatic incidence of (PET)CT positive lung hilar and retroperitoneal lymph nodes in esophageal cancer patients. Surg Oncol 2020; 33:170-176. [PMID: 32561084 DOI: 10.1016/j.suronc.2020.02.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 01/23/2020] [Accepted: 02/14/2020] [Indexed: 01/07/2023]
Abstract
BACKGROUND Extra-regional lymph node metastases strongly determine treatment options in patients with esophageal cancer. Staging modalities such as (FDG-PET) CT scanning frequently show activity in retroperitoneal and lung hilar lymph nodes. This study evaluated the incidence of histologically confirmed metastases, treatment approach and recurrence patterns in patients with (FDG-PET) CT positivity in these regions. METHODS All patients with (FDG-PET-) CT positive hilar and/or retroperitoneal lymph nodes at primary staging or restaging discussed at a multidisciplinary tumor board meeting for staging of esophageal cancer between January 2012-December 2017 were included. Biopsies and follow-up were evaluated to determine the presence of metastases and progression rates. RESULTS From 2012 to 2017, 65 of 857 patients (7.6%) were selected with positive retroperitoneal and/or hilar lymph nodes. A total of 47/65 (72.3%) patients had positive retroperitoneal lymph nodes, which contained metastases in 19 (29.2%). When no biopsy was performed and curative treatment was given (n = 14), 9 patients had progression or locoregional and distant recurrence. Positive hilar lymph nodes were identified in 21 (32.3%) patients; 4 were biopsied and none contained metastases. In these patients no recurrence of disease was seen during follow-up. CONCLUSIONS The majority of biopsied (PET)CT-positive retroperitoneal lymph nodes at staging contained metastases, while biopsied (PET)CT-positive hilar nodes did not. Histological evaluation of (PET)CT -positive retroperitoneal lymph nodes at staging imaging is recommended, while based on this small series, (PET)CT-positive hilar lymph nodes most likely represent reactive lymphadenopathy.
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Even late may still be brain, but be careful. J Neurol Sci 2019. [DOI: 10.1016/j.jns.2019.10.498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Time to CA19.9 nadir: a clue for defining treatment duration of primary chemotherapy in resectable PDAC. Ann Oncol 2019. [DOI: 10.1093/annonc/mdz156.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Correlating diameter, mechanical and structural properties of poly(l-lactide) fibres from needleless electrospinning. Acta Biomater 2018; 81:169-183. [PMID: 30273744 DOI: 10.1016/j.actbio.2018.09.055] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 08/16/2018] [Accepted: 09/27/2018] [Indexed: 10/28/2022]
Abstract
The development and application of nanofibres requires a thorough understanding of the mechanical properties on a single fibre level including respective modelling tools for precise fibre analysis. This work presents a mechanical and morphological study of poly-l-lactide nanofibres developed by needleless electrospinning. Atomic force microscopy (AFM) and micromechanical testing (MMT) were used to characterise the mechanical response of the fibres within a diameter range of 200-1400 nm. Young's moduli E determined by means of both methods are in sound agreement and show a strong increase for thinner fibres below a critical diameter of 800 nm. Similar increasing trends for yield stress and hardening modulus were measured by MMT. Finite element analyses show that the common practice of modelling three-point bending tests with either double supported or double clamped beams is prone to significant bias in the determined elastic properties, and that the latter is a good approximation only for small diameters. Therefore, an analytical formula based on intermediate boundary conditions is proposed that is valid for the whole tested range of fibre diameters, providing a consistently low error in axial Young's modulus below 10%. The analysis of fibre morphology by differential scanning calorimetry and 2D wide-angle X-ray scattering revealed increasing polymer chains alignment in the amorphous phase and higher crystallinity of fibres for decreasing diameter. The combination of these observations with the mechanical characterisation suggests a linear relationship between Young's modulus and both crystallinity and molecular orientation in the amorphous phase. STATEMENT OF SIGNIFICANCE: Fibrous membranes have rapidly growing use in various applications, each of which comes with specific property requirements. However, the development and production of nanofibre membranes with dedicated mechanical properties is challenging, in particular with techniques suitable for industrial scales such as needleless electrospinning. It is therefore a key step to understand the mechanical and structural characteristics of single nanofibres developed in this process, and to this end, the present work presents changes of internal fibre structure and mechanical properties with diameter, based on dedicated models. Special attention was given to the commonly used models for analyzing Young's modulus of single nanofibers in three-point bending tests, which are shown to be prone to large errors, and an improved robust approach is proposed.
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Corrugated diaphragm shape design study for hemocompatible pulsatile ventricular assist devices. Comput Methods Biomech Biomed Engin 2018; 21:399-407. [PMID: 29996696 DOI: 10.1080/10255842.2018.1434623] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
We aim to maximize the pumping volume of a pulsatile ventricular assist device, where the diaphragm is covered with an endothelial cell layer. These cells are estimated to survive a cyclic strain up to fifteen percent. To increase the pumping volume under this strain constraint we use an approach based on corrugation of the diaphragm in its reference configuration. The paper explains the parametrization scheme for finding corrugation shapes, addresses modeling and evaluation schemes and reports on the results of a parameter study. The results show that corrugated diaphragm shapes are effective for increasing pumping volumes under a strain constraint.
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Somatomedin C (IGF I) plasma levels after orthotopic liver transplantation (OLT) in end-stage cirrhotic patients. Transpl Int 2018. [DOI: 10.1111/tri.1992.5.s1.185] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Experimental and Numerical Characterization of the Mechanical Masseter Muscle Response During Biting. J Biomech Eng 2018; 139:2649336. [PMID: 28813570 DOI: 10.1115/1.4037592] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Indexed: 12/11/2022]
Abstract
Predictive simulations of the mastication system would significantly improve our understanding of temporomandibular joint (TMJ) disorders and the planning of cranio-maxillofacial surgery procedures. Respective computational models must be validated by experimental data from in vivo characterization of the mastication system's mechanical response. The present pilot-study demonstrates the feasibility of a combined experimental and numerical procedure to validate a computer model of the masseter muscle. An experimental setup is proposed that provides a simultaneous bite force measurement and ultrasound-based visualization of muscle deformation. The direct comparison of the experimentally observed and numerically predicted muscle response demonstrates the predictive capabilities of such anatomically accurate biting models. Differences between molar and incisor biting are investigated; muscle deformation is recorded for three different bite forces in order to capture the effect of increasing muscle fiber recruitment. The three-dimensional (3D) muscle deformation at each bite position and force-level is approximatively reconstructed from ultrasound measurements in five distinct cross-sectional areas (four horizontal and one vertical cross section). The experimental work is accompanied by numerical simulations to validate the predictive capabilities of a constitutive muscle model previously formulated. An anatomy-based, fully 3D model of the masseter muscle is created from magnetic resonance images (MRI) of the same subject. The direct comparison of experimental and numerical results revealed good agreement for maximum bite forces and masseter deformations in both biting positions. The present work therefore presents a feasible in vivo measurement system to validate numerically predicted masseter muscle contractions during mastication.
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EP-1449: Neoadjuvant chemoradiotherapy IG-IMRT PET based in esophageal or esophageal gastric junction cancer. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)31758-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Incidence of Sepsis in Central Venous Catheter-Bearing Patients with Hematologic Malignancies: Preliminary Results. J Vasc Access 2018; 5:168-73. [PMID: 16596561 DOI: 10.1177/112972980400500406] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background Indwelling central venous catheters (CVCs) are essential devices in the management of patients with hematological disorders treated with chemotherapy. However, their nature predisposes patients to unwanted complications. Methods CVC-related complications were retrospectively analyzed in 227 hematologic patients who were consecutively admitted to our hematology department between May 2002 and April 2004. Patients’ diagnoses comprised acute myeloid leukemia (36.8%), acute lymphoid leukemia (7.3%), lymphoproliferative disorders (28.3%), multiple myeloma (19.5%), myeloproliferative syndromes (5%) and others (3.1%). The CVCs used were polyurethane three lumen 7-Fr (111 patients) for chemotherapy and 12-Fr (114 patients) for chemotherapy and peripheral blood stem cell apheresis, plus two tunneled catheters. Results The pathological events were: bacteriaemias (n=46); occlusions (n=10); exit tunnel infections (n=8); thrombosis (n=6); lung emboli (n=2). Among febrile patients the bacteriemia frequency was 20%, of which 13.6% were CVC-related (with a higher incidence in leukemia patients (p=0.027). Among the isolates, gram-positive bacteria were found in 29 cases (23 CVC-related cases), and gram-negative bacteria in 16 cases (8 CVC-related cases). Only one patient had Candida albicans sepsis. At univariate and multivariate analysis significant risk factors for infection (p<0.0001) were only the number of days/catheters and neutropenia duration. Conclusions In our hematologic patients, the CVC complications were mainly septic, with only 10.1% of CVC-related bacteriemias, despite prolonged catheterization duration. Acute leukemia patients were at major risk for sepsis, probably due to a more severe neutropenia and prolonged catheterization duration.
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Discerning functional alteration from structural damage for reliable prognosis. J Neurol Sci 2017. [DOI: 10.1016/j.jns.2017.08.3624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Immunological status in acute stroke. J Neurol Sci 2017. [DOI: 10.1016/j.jns.2017.08.3626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Randomized phase 2 trial of nab-paclitaxel plus gemcitabine, ± capecitabine, cisplatin (PAXG regimen) in metastatic pancreatic adenocarcinoma. Ann Oncol 2017. [DOI: 10.1093/annonc/mdx369.122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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The suture retention test, revisited and revised. J Mech Behav Biomed Mater 2017; 77:711-717. [PMID: 28867371 DOI: 10.1016/j.jmbbm.2017.08.021] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 08/10/2017] [Accepted: 08/15/2017] [Indexed: 11/16/2022]
Abstract
A systematic investigation of the factors affecting the suture retention test is performed. The specimen width w and the distance a of the suture bite from the specimen free edge emerge as the most influential geometrical parameters. A conservative approach for the quantification of suture retention strength is identified, based on the use of a camera to monitor the incipient failure and detect the instant of earliest crack propagation. The corresponding critical force, called break starting strength, is extremely robust against test parameter variations and its dependence on the specimen geometry becomes negligible when a≥ 2mm and w≥ 10mm. Comparison of suture retention and mode I crack opening tests reveals a linear correlation between break starting strength and tearing energy. This suggests that the defect created by the needle and the load applied by the suture thread lead to a fracture mechanics problem, which dominates the initiation of failure.
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Radiofrequency versus microwave ablation for treatment of the lung tumours: LUMIRA (lung microwave radiofrequency) randomized trial. Med Oncol 2017; 34:96. [PMID: 28417355 DOI: 10.1007/s12032-017-0946-x] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 04/04/2017] [Indexed: 12/24/2022]
Abstract
The LUMIRA trial evaluated the effectiveness of radiofrequency (RFA) and microwave ablation (MWA) in lung tumours ablation and defining more precisely their fields of application. It is a controlled prospective multi-centre random trial with 1:1 randomization. Fifty-two patients in stage IV disease (15 females and 37 males, mean age 69 y.o., range 40-87) were included. We randomized the patients in two different subgroups: MWA group and RFA group. For each group, we evaluated the technical and clinical success, the overall survival and complication rate. Inter-group difference was compared using Chi-square test or Fisher's exact test for categorical variables and one-way ANOVA test for continuous variables. For RFA group, there was a significant reduction in tumour size only between 6 and 12 months (p value = 0.0014). For MWA group, there was a significant reduction in tumour size between 6 and 12 months (p value = 0.0003) and between pre-therapy and 12 months (p value = 0.0215). There were not significant differences between the two groups in terms of survival time (p value = 0.883), while the pain level in MWA group was significantly less than in RFA group (1.79 < 3.25, p value = 0.0043). In conclusion, our trial confirms RFA and MWA are both excellent choices in terms of efficacy and safety in lung tumour treatments. However, when compared to RFA therapy, MWA produced a less intraprocedural pain and a significant reduction in tumour mass.
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Abstract
Avascular necrosis (AVN) of the femoral head (FH) causes 5% to 12% of total hip arthroplasties (THA). It especially affects active male adults between the third and fifth decades of life. The exact worldwide incidence is unknown. There are only few data related to each country, but most of it relates to the United States.Non-surgical management has a very limited role in the treatment of AVN of the FH and only in its earliest stages. Core decompression (CD) of the hip is the most common procedure used to treat the early stages of AVN of the FH. Recently, surgeons have considered combining CD with autologous bone-marrow cells, demineralised bone matrix or bone morphogenetic proteins or methods of angiogenic potential to enhance bone repair in the FH.Manuscripts were deemed eligible for our review if they evaluated treatment of early stage AVN of the FH with biotechnology implanted via CD. After application of eligibility criteria, we selected 19 reports for final analysis.The principal results showed that only by correctly mastering the therapeutic principles and adopting proper methods specifically oriented to different stages can the best therapeutic effect be achieved. Combining CD with biotechnology could result in a novel long-lasting hip- preserving treatment option.Furthermore, more refined clinical studies are needed to establish the effectiveness of biotechnology treatments in AVN of the FH. Cite this article: EFORT Open Rev 2017;2:41-50. DOI: 10.1302/2058-5241.2.150006.
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SysMyo: tailored bioinformatics tools for omics data exploration in muscular dystrophy and other neuromuscular disorders. Neuromuscul Disord 2017. [DOI: 10.1016/s0960-8966(17)30239-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Cervical softening occurs early in pregnancy: characterization of cervical stiffness using the aspiration technique. Geburtshilfe Frauenheilkd 2016. [DOI: 10.1055/s-0036-1592905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Experimental and theoretical analyses of the age-dependent large-strain behavior of Sylgard 184 (10:1) silicone elastomer. J Mech Behav Biomed Mater 2016; 60:425-437. [DOI: 10.1016/j.jmbbm.2016.02.022] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 02/11/2016] [Accepted: 02/13/2016] [Indexed: 12/24/2022]
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Simultaneous Liver-Kidney Transplantation in Adults: A Single-center Experience Comparing Results With Isolated Liver Transplantation. Transplant Proc 2016; 47:2156-8. [PMID: 26361666 DOI: 10.1016/j.transproceed.2014.11.073] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2014] [Accepted: 11/19/2014] [Indexed: 12/17/2022]
Abstract
BACKGROUND After introduction of the Model for End-Stage Liver Disease (MELD) score in 2002, a worldwide increasing number of simultaneous liver-kidney transplantations (SLKTx) has been observed. However, organ shortage puts into question the allocation of 2 grafts to 1 recipient. This retrospective, single-center study compared SLKTx results with isolated liver transplantation (LTx). METHODS Between 1995 and 2013, 37 SLKTx were performed in adult recipients. Every SLKTx was matched by donor age (±5 years) and transplantation date with 2 LTx (n = 74). Pretransplant, intraoperative, and post-transplant variables were collected; liver graft and patient survivals were calculated. RESULTS As expected, donor age was similar in the 2 groups (median, 39.7 years), whereas serum creatinine level, glomerular filtration rate, and MELD and D-MELD (donor age*MELD) scores were significantly higher in the SLKTx group. SLKTx had longer waiting list time (P = .0034) as well as higher surgical difficulty, testified by more blood transfusions (P = .0083), increased use of classic caval reconstruction (P = .0024), and more frequent need of abdominal packing for bleeding control (P = .0003). In addition, duration of hospital stay (P < .0001), second-look surgery (P = .0082), post-transplant dialysis (P < .0001), and post-transplant infections (P = .04) were significantly greater in SLKTx group. Acute rejection episodes involving the liver were significantly less in SLKTx than in LTx (14% vs 41%; P = .0045). Liver graft and patient survival at 10 years after transplantation was similar in the 2 groups (liver graft: SLKTx, 80% vs LTx, 77% [P = .85]; patient: SLKTx, 86% vs LTx, 79% [P = .56]). CONCLUSIONS Despite being technically challenging, SLKTx provided excellent long-term results and was shown to be an effective use of liver grafts.
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Objective Assessment of Cervical Stiffness after Administration of Misoprostol for Intrauterine Contraceptive Insertion. Ultrasound Int Open 2016; 2:E63-7. [PMID: 27689173 DOI: 10.1055/s-0042-106393] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 03/22/2016] [Indexed: 10/21/2022] Open
Abstract
PURPOSE The goal of this study was to objectively quantify cervical stiffness in misoprostol users prior to IUC insertion and at follow-up consultation to evaluate the feasibility of assessing cervical stiffness and to study the influence of misoprostol on cervical softening. MATERIALS AND METHODS This was a cross-sectional study that evaluated 40 women who wished to use the LNG IUS. These women were evaluated immediately before LNG IUS insertion and 6 weeks later at follow-up consultation. Participants received 200 μg of misoprostol combined with 75 mg of diclofenac in a single tablet orally (Arthrotec forte 75/200(®), Pfizer, USA) 6-12 h prior to insertion in "off label" use. On both occasions, cervical stiffness was determined using a novel medical device based on the aspiration technique. The Wilcoxon rank-sum and the Wilcoxon signed-rank test were applied to compare cervical stiffness assessments at insertion of the IUD and at follow-up. RESULTS For the first time, cervical stiffness was quantitatively assessed in misoprostol users prior to IUD insertion, proving that the aspiration technique enables detection of pharmacologically induced cervical changes, and also that misoprostol has a detectable softening effect on cervical tissue. CONCLUSION The clinical value of the detected cervical softening after misoprostol administration remains unclear. Aspiration measurements could be helpful in searching for the ideal candidate, the appropriate route, dosage and interval of misoprostol intake prior to IUC insertion.
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Suction based mechanical characterization of superficial facial soft tissues. J Biomech 2015; 48:4279-86. [PMID: 26584965 DOI: 10.1016/j.jbiomech.2015.10.039] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 10/15/2015] [Accepted: 10/25/2015] [Indexed: 10/22/2022]
Abstract
The present study is aimed at a combined experimental and numerical investigation of the mechanical response of superficial facial tissues. Suction based experiments provide the location, time, and history dependent behavior of skin and SMAS (superficial musculoaponeurotic system) by means of Cutometer and Aspiration measurements. The suction method is particularly suitable for in vivo, multi-axial testing of soft biological tissue including a high repeatability in subsequent tests. The campaign comprises three measurement sites in the face, i.e. jaw, parotid, and forehead, using two different loading profiles (instantaneous loading and a linearly increasing and decreasing loading curve), multiple loading magnitudes, and cyclic loading cases to quantify history dependent behavior. In an inverse finite element analysis based on anatomically detailed models an optimized set of material parameters for the implementation of an elastic-viscoplastic material model was determined, yielding an initial shear modulus of 2.32kPa for skin and 0.05kPa for SMAS, respectively. Apex displacements at maximum instantaneous and linear loading showed significant location specificity with variations of up to 18% with respect to the facial average response while observing variations in repeated measurements in the same location of less than 12%. In summary, the proposed parameter sets for skin and SMAS are shown to provide remarkable agreement between the experimentally observed and numerically predicted tissue response under all loading conditions considered in the present study, including cyclic tests.
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Clinical practice and decision making in as. J Neurol Sci 2015. [DOI: 10.1016/j.jns.2015.08.1339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Challenging the in-vivo assessment of biomechanical properties of the uterine cervix: A critical analysis of ultrasound based quasi-static procedures. J Biomech 2015; 48:1541-8. [PMID: 25791058 DOI: 10.1016/j.jbiomech.2015.02.038] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 02/17/2015] [Indexed: 01/14/2023]
Abstract
Measuring the stiffness of the uterine cervix might be useful in the prediction of preterm delivery, a still unsolved health issue of global dimensions. Recently, a number of clinical studies have addressed this topic, proposing quantitative methods for the assessment of the mechanical properties of the cervix. Quasi-static elastography, maximum compressibility using ultrasound and aspiration tests have been applied for this purpose. The results obtained with the different methods seem to provide contradictory information about the physiologic development of cervical stiffness during pregnancy. Simulations and experiments were performed in order to rationalize the findings obtained with ultrasound based, quasi-static procedures. The experimental and computational results clearly illustrate that standardization of quasi-static elastography leads to repeatable strain values, but for different loading forces. Since force cannot be controlled, this current approach does not allow the distinction between a globally soft and stiff cervix. It is further shown that introducing a reference elastomer into the elastography measurement might overcome the problem of force standardization, but a careful mechanical analysis is required to obtain reliable stiffness values for cervical tissue. In contrast, the maximum compressibility procedure leads to a repeatable, semi-quantitative assessment of cervical consistency, due to the nonlinear nature of the mechanical behavior of cervical tissue. The evolution of cervical stiffness in pregnancy obtained with this procedure is in line with data from aspiration tests.
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Mechanical biocompatibility of prosthetic meshes: A comprehensive protocol for mechanical characterization. J Mech Behav Biomed Mater 2014; 40:42-58. [DOI: 10.1016/j.jmbbm.2014.08.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 07/29/2014] [Accepted: 08/10/2014] [Indexed: 11/27/2022]
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Abstract
INTRODUCTION The recent evolution of prosthesis technology has enabled the surgeon to replace entire limbs. These special prostheses, or megaprostheses, were developed for the treatment of severe oncological bone loss; however, the indications and applications of these devices have expanded to other orthopaedic and trauma situations. For some years, surgeons have been implanting megaprostheses in non-oncological conditions, such as acute trauma in severe bone loss and poor bone quality; post-traumatic failures, both aseptic and septic (represented by complex non-unions and critical size bone defects); major bone loss in prosthetic revision, both aseptic and septic; periprosthetic fractures with component mobilisation and poor bone stock condition. The purpose of this study was to evaluate retrospectively the complications during and after the implantation of megaprosthesis of the lower limb in post-traumatic and prosthetic bone loss, and to propose tips about how to avoid and manage such complications. MATERIALS AND METHODS All the complications and difficulties we have encountered during or after the implantation of megaprosthesis in non-oncology patients were evaluated retrospectively. A total of 72 patients were treated with large resection mono-and bi-articular prostheses between January 2008 and January 2014. RESULTS The main critical problems found in the study were: restoration of the correct length and rotation of the limb; reconstruction of the knee extensor mechanism; trochanteric reconstruction; stability/dislocation of the implant; mobility/range of motion (ROM) of the implant; skin cover; sepsis, and bone quality. CONCLUSION Megaprosthesis in severe bone loss can be considered as an available solution for the orthopaedic surgeon in extreme, appropriately selected cases. This type of complex surgery must be performed in specialised centres where knowledge and technologies are present. Patients with severe bone loss should not be treated in the same way as oncology patients because life expectancy is definitely longer; therefore, the surgical technique and the system implantation must be extremely rigorous to ensure longevity of the prosthesis. The characteristics of the bone and soft tissue conditions in these patients are very different from those presented by oncology patients, which creates critical problems that the surgeon should be able to manage to avoid serious complications.
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A physically motivated constitutive model for 3D numerical simulation of skeletal muscles. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2014; 30:545-562. [PMID: 24421263 DOI: 10.1002/cnm.2618] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 09/26/2013] [Accepted: 11/08/2013] [Indexed: 06/03/2023]
Abstract
A detailed numerical implementation within the FEM is presented for a physically motivated three-dimensional constitutive model describing the passive and active mechanical behaviors of the skeletal muscle. The derivations for the Cauchy stress tensor and the consistent material tangent are provided. For nearly incompressible skeletal muscle tissue, the strain energy function may be represented either by a coupling or a decoupling of the distortional and volumetric material response. In the present paper, both functionally different formulations are introduced allowing for a direct comparison between the coupled and decoupled isochoric-volumetric approach. The numerical validation of both implementations revealed significant limitations for the decoupled approach. For an extensive characterization of the model response to different muscle contraction modes, a benchmark model is introduced. Finally, the proposed implementation is shown to provide a reliable tool for the analysis of complex and highly nonlinear problems through the example of the human mastication system by studying bite force and three-dimensional muscle shape changes during mastication.
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Treatment of AVN using the induction chamber technique and a biological-based approach: indications and clinical results. Injury 2014; 45:369-73. [PMID: 24119830 DOI: 10.1016/j.injury.2013.09.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/17/2013] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To determine the efficacy of core decompression (CD) technique combined with recombinant morphogenetic proteins, autologous mesenchymal stem cells (MSCs) and xenograft bone substitute into the necrotic lesion of the femoral head on clinical symptoms and on the progression of osteonecrosis of the femoral head. PATIENTS AND METHODS A total of 38 patients (40 hips) with early stage osteonecrosis of the femoral head were studied over a 4-year period. RESULTS CD technique combined with recombinant morphogenetic proteins, autologous MSCs and xenograft bone substitute was associated with a significant reduction in both pain and joint symptoms and reduced the incidence of fractural stages. At 36 months, 33 patients achieved clinical and radiographic healing. CONCLUSION This long-term follow-up study confirmed that CD technique combined with recombinant morphogenetic proteins, autologous MSCs and xenograft bone substitute may be an effective treatment for patients with early stage osteonecrosis of the femoral head.
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Abstract
INTRODUCTION The development of new megaprosthesis for the treatment of large bone defects provides important options to orthopaedic oncologic surgeons for the replacement of skeletal segments, such as the long bones of the upper and lower limbs and the relative joints. We implanted megaprosthesis using either a one-step or two-step technique depending on the patient's condition. The aim of this study was to evaluate retrospectively both clinical and radiological outcomes in patients who underwent lower limb megaprosthesis implant. MATERIALS AND METHODS A total of 32 patients were treated with mono- and bi-articular megaprosthesis subdivided as follows: proximal femur, distal femur, proximal tibia and total femur. The mean follow-up of patients was about 18 months (range 3 months to 5 years). Clinical and serial radiographic evaluations were conducted using standard methods (X-ray at 45 days, 3, 6, 12, 18 and 24 months) and blood parameters of inflammation were monitored for at least 2 months. RESULTS Although the mean length of follow-up was only 18 months, the first patients to enter the study were monitored for 5 years and showed encouraging clinical results, with good articulation of the segments, no somato-sensory or motor deficit and acceptable functional recovery. During surgery and, more importantly, in pre-operative planning, much attention should be given to the evaluation of the extensor apparatus, preserving it and, when necessary, reinforcing it with tendon substitutes. DISCUSSION Megaprosthesis in extreme cases of severe bone loss and prosthetic failure is a potential solution for the orthopaedic surgeon. In oncological surgery, the opportunity to restore functionality to the patient (although not ad integrum) is important for both the patient and the surgeon. The high mortality associated with cancer precludes long-term patient follow-up; therefore, there is a lack of certainty about the survival of this type of prosthesis and any medium- to long-term complications that may occur. Nevertheless, patients should be considered as an oncologic patient, not because of the disease, but because of the limited therapeutic options available. CONCLUSIONS Megaprosthesis provides a valuable opportunity to restore functionality to patients with highly disabling diseases.
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Uniaxial and biaxial mechanical characterization of a prosthetic mesh at different length scales. J Mech Behav Biomed Mater 2014; 29:7-19. [DOI: 10.1016/j.jmbbm.2013.07.021] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 07/24/2013] [Accepted: 07/26/2013] [Indexed: 11/24/2022]
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Mussel mimetic tissue adhesive (mussel glue) for fetal membrane repair in vivo. Z Geburtshilfe Neonatol 2013. [DOI: 10.1055/s-0033-1361202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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42
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Systemic allostatic overload in acute stroke. J Neurol Sci 2013. [DOI: 10.1016/j.jns.2013.07.774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Second harmonic generation microscopy of fetal membranes under deformation: normal and altered morphology. Placenta 2013; 34:1020-6. [PMID: 24070621 DOI: 10.1016/j.placenta.2013.09.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 09/02/2013] [Accepted: 09/05/2013] [Indexed: 11/20/2022]
Abstract
INTRODUCTION Insight into the microstructure of fetal membrane and its response to deformation is important for understanding causes of preterm premature rupture of the membrane. However, the microstructure of fetal membranes under deformation has not been visualized yet. Second harmonic generation microscopy, combined with an in-situ stretching device, can provide this valuable information. METHODS Eight fetal membranes were marked over the cervix with methylene blue during elective caesarean section. One sample per membrane of reflected tissue, between the placenta and the cervical region, was cyclically stretched with a custom built inflation device. Samples were mounted on an in-situ stretching device and imaged with a multiphoton microscope at different deformation levels. Microstructural parameters such as thickness and collagen orientation were determined. Image entropy was evaluated for the spongy layer. RESULTS The spongy layer consistently shows an altered collagen structure in the cervical and cycled tissue compared with the reflected membrane, corresponding to a significantly higher image entropy. An increased thickness of collagenous layers was found in cervical and stretched samples in comparison to the reflected tissue. Significant collagen fibre alignment was found to occur already at moderate deformation in all samples. CONCLUSIONS For the first time, second harmonic generation microscopy has been used to visualize the microstructure of fetal membranes. Repeated mechanical loading was shown to affect the integrity of the amnion-chorion interface which might indicate an increased risk of premature rupture of fetal membrane. Moreover, mechanical loading might contribute to morphological alterations of the fetal membrane over the cervical region.
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Mussel mimetic tissue adhesive for fetal membrane repair: initial in vivo investigation in rabbits. Eur J Obstet Gynecol Reprod Biol 2013; 171:240-5. [PMID: 24075447 DOI: 10.1016/j.ejogrb.2013.09.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2013] [Revised: 07/31/2013] [Accepted: 09/02/2013] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Iatrogenic preterm prelabour rupture of fetal membranes (iPPROM) remains the main complication after invasive interventions into the intrauterine cavity. The aim of this study was to evaluate the sealing capability and tissue interaction of mussel-mimetic tissue adhesive (mussel glue) in comparison to fibrin glue on punctured fetal membranes in vivo. STUDY DESIGN A mid-gestational rabbit model was used for testing the materials. The fetal sacs of pregnant rabbits at day 23 were randomly assigned into experimental groups: unoperated (negative control), unclosed puncture (positive control), commercially available fibrin glue (FG) with decellularized amnion scaffold (DAM), mussel glue (MG) with DAM, or mussel glue alone. Evaluation was done at term (30 days' gestation) assessing fetal survival, fetal membrane integrity and histology of the membranes. RESULTS Fetal survival was not significantly lower in any of the treatment groups compared to the negative control. All plugging materials could be found at the end of the pregnancy and no adverse effects on the fetus or the pregnant does could be observed. Sac integrity was higher in all treatment groups compared to the positive control group but significant only in the FG+DAM group. Cellular infiltration could be seen in fibrin glue and DAM in contrast to mussel glue which was only tightly adhering to the surrounding tissue. These cells were mostly of mesenchymal phenotype staining positive for vimentin. CD68 positive macrophages were found clustered around all the plugging materials, but their numbers were only significantly increased for the mussel glue alone group compared to negative controls. CONCLUSIONS Mussel glues performance in sealing fetal membranes in the rabbit model was comparable to that of fibrin glue. Taking into account its other favorable properties, it is a noteworthy candidate for a clinically applicable fetal membrane sealant.
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Breast metastases from oligodendroglioma: an unusual extraneural spread in two young women and a review of the literature. Crit Rev Oncol Hematol 2013; 88:564-72. [PMID: 23953683 DOI: 10.1016/j.critrevonc.2013.07.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 06/05/2013] [Accepted: 07/18/2013] [Indexed: 10/26/2022] Open
Abstract
BACKGROUND Extraneural dissemination of oligodendroglioma is rare. Cases of breast metastases have never been described in the literature. CASE REPORTS We report the first two cases of young women with initial diagnosis of anaplastic oligodendroglioma who experienced mammary gland metastases and a review of the literature. RESULTS Immunohistochemical analysis performed on material from both primary and metastatic sites did not allow to draw any conclusion on possible etiopathogenetic hypothesis. A review of literature yielded 35 cases of extracranial metastatic oligodendroglioma from 1989 to 2012. CONCLUSION Though rare, extracranial dissemination from oligodendroglioma may occur not only in long surviving heavily pre-treated patients. The review of literature and these two cases suggest that spread is primarily to bone and then from bone to other organs through hematogenous route mostly due to leptomeningeal or dura mater invasion. Chemotherapy regimens similar to those commonly used for non metastatic oligodendroglioma are recommended for patients with good performance status.
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Multiaxial mechanical behavior of human fetal membranes and its relationship to microstructure. Biomech Model Mechanobiol 2013; 12:747-762. [PMID: 22972367 DOI: 10.1007/s10237-012-0438] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Accepted: 08/30/2012] [Indexed: 05/28/2023]
Abstract
This study was directed to the measurement of the mechanical response of fetal membranes to physiologically relevant loading conditions. Characteristic mechanical parameters were determined and their relation to the microstructural constituents collagen and elastin as well as to the pyridinium cross-link concentrations analyzed. 51 samples from twelve fetal membranes were tested on a custom-built inflation device, which allows mechanical characterization within a multiaxial state of stress. Methods of nonlinear continuum mechanics were used to extract representative mechanical parameters. Established biochemical assays were applied for the determination of the collagen and elastin content. Collagen cross-link concentrations were determined by high-performance liquid chromatography measurements. The results indicate a distinct correlation between the mechanical parameters of high stretch stiffness and membrane tension at rupture and the biochemical data of collagen content and pyridinoline as well as deoxypyridinoline concentrations. No correlation was observed between the mechanical parameters and the elastin content. Moreover, the low stretch stiffness is, with a value of 105 ± 31 × 10(-3) N/ mm much higher for a biaxial state of stress compared to a uniaxial stress configuration. Determination of constitutive model equations leads to better predictive capabilities for a reduced polynomial hyperelastic model with only terms related to the second invariant, I 2, of the right Cauchy-Green deformation tensor. Relevant insights were obtained on the mechanical behavior of fetal membranes. Collagen and its cross-linking were shown to determine membrane's stiffness and strength for multiaxial stress states. Their nonlinear deformation behavior characterizes the fetal membranes as I 2 material.
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Weekly Epirubicin as Salvage Therapy in Patients with Gemcitabine-Resistant Advanced Pancreatic Cancers. J Chemother 2013; 21:698-700. [DOI: 10.1179/joc.2009.21.6.698] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Combined biaxial and uniaxial mechanical characterization of prosthetic meshes in a rabbit model. J Biomech 2013; 46:1626-32. [DOI: 10.1016/j.jbiomech.2013.04.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Revised: 04/09/2013] [Accepted: 04/14/2013] [Indexed: 01/27/2023]
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A non-biological model system to simulate the in vivo mechanical behavior of prosthetic meshes. J Mech Behav Biomed Mater 2013; 20:305-15. [DOI: 10.1016/j.jmbbm.2013.01.029] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 01/15/2013] [Accepted: 01/28/2013] [Indexed: 10/27/2022]
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Abstract
OBJECTIVE To determinate the efficacy of "polytherapy", a surgical technique that utilize all the components of the diamond concept (mesenchymal stem cells, bone morphogenetic proteins and scaffold) versus a "monotherapy", a surgical technique that utilize only one component of the diamond conceptin the treatment of severe forearm non-unions. METHODS We studied a database of 52 patients with 52 forearm non-unions; we classified the patients with the NUSS SCORE and we divided the patients in two group according to the treatment received. So we distinguished a group of patients treated according to the principles of "monotherapy" (33 patients) and a group of patients treated according to the principles of "polytherapy" (19 patients). The minimum follow up was 12 months. RESULTS In the monotherapy group 21/33 non-unions (63.64%) went on to develop a radiographic and clinical healing within a period of 12 months, the calculated DASH SCORE showed a mean value of 55.15 points. In the polytherapy group 17/19 (89.47%) nonunions went on to develop clinical and radiographic healing within 12 months, and the average DASH score showed a mean value of 45.47 points. CONCLUSION The polytherapy technique with the use of recombinant morphogenetic proteins, autologous MSCs and scaffold in the same surgical time appears to be an effective treatment for patients with severe forearm non-unions.
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