106 research outputs found

    Breathing new life into tissue engineering: exploring cutting-edge vascularization strategies for skin substitutes

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    Tissue-engineered skin substitutes (TESS) emerged as a new therapeutic option to improve skin transplantation. However, establishing an adequate and rapid vascularization in TESS is a critical factor for their clinical application and successful engraftment in patients. Therefore, several methods have been applied to improve the vascularization of skin substitutes including (i) modifying the structural and physicochemical properties of dermal scaffolds; (ii) activating biological scaffolds with growth factor-releasing systems or gene vectors; and (iii) developing prevascularized skin substitutes by loading scaffolds with capillary-forming cells. This review provides a detailed overview of the most recent and important developments in the vascularization strategies for skin substitutes. On the one hand, we present cell-based approaches using stem cells, microvascular fragments, adipose tissue derived stromal vascular fraction, endothelial cells derived from blood and skin as well as other pro-angiogenic stimulation methods. On the other hand, we discuss how distinct 3D bioprinting techniques and microfluidics, miRNA manipulation, cell sheet engineering and photosynthetic scaffolds like GelMA, can enhance skin vascularization for clinical applications. Finally, we summarize and discuss the challenges and prospects of the currently available vascularization techniques that may serve as a steppingstone to a mainstream application of skin tissue engineering

    Quantitative Analysis of Challenges Encountered by UK Widening Participation Medical Students in Comparison With Their Non-Widening Participation Peers

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    OBJECTIVES Few studies have captured the experiences of widening participation (WP) medical students, and none have compared their experiences to their non-WP peers. This study aims to identify which challenges WP students are more likely to face.METHODS A 22-item questionnaire was distributed to medical students across all UK medical schools. Students were asked yes or no questions on whether they faced challenges in finances, socializing, physical and mental health, academic attainment, and COVID19-related teaching changes.RESULTS One-hundred seventy-six medical students from all year groups across the UK responded, with 97 students from a WP background. WP students were significantly more likely to have their personal background impacting their mental health (OR = 2.65, WP  =  0.002), more than twice as likely to feel that their job impacted their studies (OR = 2.53, P ≤.05), more likely to feel limited by their financial situation (OR = 2.29, P≤.05) and to receive support from student finance (OR = 2.08, P \u3c .05).CONCLUSION WP students were more likely to face challenges in mental health and finances in medical school compared to their peers. These findings, further informed by qualitative insights can aid in advancing equity in medical training

    Cytogenetic diagnosis of Roberts SC phocomelia syndrome: First report from Kashmir

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    There are several syndromes in which specific mitotic chromosomal abnormalities can be seen, like premature centromere separation, premature (sister) chromatid separation, and somatic aneuploidies. Identifications of such specific cytogenetic findings can be the key factor that leads towards the diagnosis of syndromes like Roberts SC phocomelia. The case presented here as Roberts SC phocomelia syndrome was identified as a child with multiple congenital anomalies and dysmorphic features. Conventional cytogenetic analysis of the case revealed premature sister chromatid separation. The premature centromeric separation was also confirmed by C banding analysis of the child. It is the first and the only case of Roberts SC phocomelia diagnosed from this part of the world. The present case report emphasizes the importance of conventional cytogenetics in the diagnosis of such syndromes

    Differing Von Hippel Lindau Genotype in Paired Primary and Metastatic Tumors in Patients with Clear Cell Renal Cell Carcinoma

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    In sporadic clear cell renal cell carcinoma (CCRCC), the von Hippel Lindau (VHL) gene is inactivated by mutation or methylation in the majority of primary (P) tumors. Due to differing effects of wild-type (WT) and mutant (MT) VHL gene on downstream signaling pathways regulating angiogenesis, VHL gene status could impact clinical outcome. In CCRCC, comparative genomic hybridization analysis studies have reported genetic differences between paired P and metastatic (M) tumors. We thus sequenced the VHL gene in paired tumor specimens from 10 patients to determine a possible clonal relationship between the P tumor and M lesion(s) in patients with CCRCC. Using paraffin-embedded specimens, genomic DNA from microdissected samples (>80% tumor) of paired P tumor and M lesions from all 10 patients, as well as in normal tissue from 6 of these cases, was analyzed. The DNA was used for PCR-based amplification of each of the 3 exons of the VHL gene. Sequences derived from amplified samples were compared to the wild-type VHL gene sequence (GenBank Accession No. AF010238). Methylation status of the VHL gene was determined using VHL methylation-specific PCR primers after DNA bisulfite modification. In 4/10 (40%) patients the VHL gene status differed between the P tumor and the M lesion. As expected, when the VHL gene was mutated in both the P tumor and M lesion, the mutation was identical. Further, while the VHL genotype differed between the primary tumor in different kidneys or multiple metastatic lesions in the same patient, the VHL germline genotype in the normal adjacent tissue was always wild-type irrespective of the VHL gene status in the P tumor. These results demonstrate for the first time that the VHL gene status can be different between paired primary and metastatic tissue in patients with CCRCC

    Hepatoprotective effect of aqeous methanolic extract of Rumex dentatus in paracetamol induced hepatotoxicity in mice

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    Rumex dentatus is well known plant of Polygonaceae family which is widely used in traditional medicine to treat gastrointestinal tract. R. dentatus at doses 250 and 500 mg/kg significance decreased (p<0.001) the elevated level of ALT, AST, ALP and bilirubin induced by paracetamol and results are comparable (p<0.001) with silymarin. The results were supported by histopathological investigations, phytochemical screening and detection of hepatoprotective active constituents e.g quercetin, kaempferol, myricetin by HPLC. So, it is concluded that R. dentatus has hepatoprotective effect against paracetamol liver damage in mice

    Reporting transparency and completeness in trials : Paper 3 – trials conducted using administrative databases do not adequately report elements related to use of databases

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    Acknowledgments The development of CONSORT-ROUTINE and the present review were funded by grants from the Canadian Institutes of Health Research (PI Thombs, #PJT-156172; PIs Thombs and Kwakkenbos, #PCS-161863) and from the United Kingdom National Institute of Health Research (NIHR) Clinical Trials Unit Support Funding (PI Juszczak, Co-PI Gale, supported salary of SM). The views expressed are those of the author(s) and not necessarily those of the NIHR or the Department of Health and Social Care. Dr. Langan was supported by a Wellcome Senior Clinical Fellowship in Science (205039/Z/16/Z). Dr. Moher is supported by a University Research Chair (uOttawa). Dr. Gale was supported by the United Kingdom Medical Research Council through a Clinician Scientist Fellowship. Dr. Thombs was supported by a Tier 1 Canada Research Chair.Peer reviewedPublisher PD

    Individual and Contextual Factors of Sexual Risk Behavior in Youth Perinatally Infected with HIV

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    Abstract This study prospectively examines the effects of maternal and child HIV infection on youth penetrative and unprotected penetrative sex, as well as the role of internal contextual, external contextual, social and self-regulatory factors in influencing the sexual behaviors of HIV?infected (PHIV+), HIV?affected (uninfected with an HIV+ caregiver), and HIV unaffected (uninfected with an HIV? caregiver) youth over time. Data (N=420) were drawn from two longitudinal studies focused on the effects of pediatric or maternal HIV on youth (51% female; 39% PHIV+) and their caregivers (92% female; 46% HIV+). PHIV+ youth were significantly less likely to engage in penetrative sex than HIV? youth at follow-up, after adjusting for contextual, social, and self-regulatory factors. Other individual- and contextual-level factors such as youth alcohol and marijuana use, residing with a biological parent, caregiver employment, caregiver marijuana use, and youth self-concept were also associated with penetrative sex. Youth who used alcohol were significantly more likely to engage in unprotected penetrative sex. Data suggest that, despite contextual, social, and self-regulatory risk factors, PHIV+ youth are less likely to engage in sexual behavior compared to HIV? youth from similar environments. Further research is required to understand delays in sexual activity in PHIV+ youth and also to understand potential factors that promote resiliency, particularly as they age into older adolescence and young adulthood.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98470/1/apc%2E2012%2E0005.pd

    Protocol for a scoping review to support development of a CONSORT extension for randomised controlled trials using cohorts and routinely collected health data.

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    INTRODUCTION: Randomised controlled trials (RCTs) conducted using cohorts and routinely collected health data, including registries, electronic health records and administrative databases, are increasingly used in healthcare intervention research. The development of an extension of the CONsolidated Standards of Reporting Trials (CONSORT) statement for RCTs using cohorts and routinely collected health data is being undertaken with the goal of improving reporting quality by setting standards early in the process of uptake of these designs. To develop this extension to the CONSORT statement, a scoping review will be conducted to identify potential modifications or clarifications of existing reporting guideline items, as well as additional items needed for reporting RCTs using cohorts and routinely collected health data. METHODS AND ANALYSIS: In separate searches, we will seek publications on methods or reporting or that describe protocols or results from RCTs using cohorts, registries, electronic health records and administrative databases. Data sources will include Medline and the Cochrane Methodology Register. For each of the four main types of RCTs using cohorts and routinely collected health data, separately, two investigators will independently review included publications to extract potential checklist items. A potential item will either modify an existing CONSORT 2010, Strengthening the Reporting of Observational Studies in Epidemiology or REporting of studies Conducted using Observational Routinely collected health Data item or will be proposed as a new item. Additionally, we will identify examples of good reporting in RCTs using cohorts and routinely collected health data. ETHICS AND DISSEMINATION: The proposed scoping review will help guide the development of the CONSORT extension statement for RCTs conducted using cohorts and routinely collected health data

    Overestimation of Postpartum Depression Prevalence Based on a 5-item Version of the EPDS:Systematic Review and Individual Participant Data Meta-analysis

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    Objective:The Maternal Mental Health in Canada, 2018/2019, survey reported that 18% of 7,085 mothers who recently gave birth reported "feelings consistent with postpartum depression" based on scores >= 7 on a 5-item version of the Edinburgh Postpartum Depression Scale (EPDS-5). The EPDS-5 was designed as a screening questionnaire, not to classify disorders or estimate prevalence; the extent to which EPDS-5 results reflect depression prevalence is unknown. We investigated EPDS-5 >= 7 performance relative to major depression prevalence based on a validated diagnostic interview, the Structured Clinical Interview for DSM (SCID).Methods:We searched Medline, Medline In-Process & Other Non-Indexed Citations, PsycINFO, and the Web of Science Core Collection through June 2016 for studies with data sets with item response data to calculate EPDS-5 scores and that used the SCID to ascertain depression status. We conducted an individual participant data meta-analysis to estimate pooled percentage of EPDS-5 >= 7, pooled SCID major depression prevalence, and the pooled difference in prevalence.Results:A total of 3,958 participants from 19 primary studies were included. Pooled prevalence of SCID major depression was 9.2% (95% confidence interval [CI] 6.0% to 13.7%), pooled percentage of participants with EPDS-5 >= 7 was 16.2% (95% CI 10.7% to 23.8%), and pooled difference was 8.0% (95% CI 2.9% to 13.2%). In the 19 included studies, mean and median ratios of EPDS-5 to SCID prevalence were 2.1 and 1.4 times.Conclusions:Prevalence estimated based on EPDS-5 >= 7 appears to be substantially higher than the prevalence of major depression. Validated diagnostic interviews should be used to establish prevalence
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