COSMOS 2044: Lung morphology study, experiment K-7-28

Researchers examined the effect of microgravity during spaceflight on lung tissue. The ultrastructure of the left lungs of 5 Czechoslovakian Wister rats flown on the 13 day, 19+ hour Cosmos 2044 mission was examined and compared to 5 vivarium and 5 synchronous controls at 1-g conditions, and 5 rats exposed to 14 days of tail suspension. Pulmonary hemorrage and alveolar adema of unknown origin occurred to a greater extent in the flight, tail-suspended, and synchronous control animals, and in the dorsal regions of the lung when compared with the vivarium controls. The cause of these changes, which are possibly due to an increase in pulmonary vascular pressure, requires further investigation

Investigation of the mechanical strength of explanted polypropylene hernia meshes [abstract]

Abstract only availableOver twenty million hernia repair surgeries are performed worldwide each year. Many of these repairs are accomplished through the use of a prosthetic mesh material rather than sutures because meshes have been shown to reduce post-operative complications and recurrence rates. Long-term implants, such as hernia meshes, continuously activate the inflammatory response, bathing the material with oxidants such as hydrogen peroxide and hypochlorous acid. Polypropylene, the most commonly-used hernia repair material worldwide, is an aliphatic hydrocarbon, which is susceptible to oxidation. Constant exposure of the mesh to these oxidants may lead to degradation of the material over time. There is evidence that many patients experience chronic pain and/or embrittlement of the mesh material over time, particularly for polypropylene hernia mesh materials. For this reason, mechanical testing was utilized to characterize polypropylene meshes explanted from human subjects to determine if oxidative degradation could play a role in these changes. We expected to find a decrease in the overall strength and percent elongation of the materials and increase in Young's Modulus after exposure to the harsh biological environment.College of Engineering Undergraduate Research Optio

Assessing biocompatibility of porcine tissue for hernia repair using flow cytometry [abstract]

Abstract only availableThe current standard for abdominal hernia repair uses synthetic meshes, which often break down, leading to complications and a high rate of recurrence. A biologic prosthetic, derived from animal tissue, would provide a more natural substrate for tissue remodeling and an improved host response. The success of a biologic material for tissue repair first depends on preventing an immune reaction post implantation. Engineering an appropriate construct requires removal of cells from the donor tissue, stabilization of the resulting collagen matrix with cross-linkers, and sterilization prior to implantation. The central tendon of the porcine diaphragm is a novel material for use as a biologic implant. This study is a preliminary investigation of the biocompatibility of porcine diaphragm as a hernia mesh material. Diaphragm tissue was de-cellularized by one of two methods and cross-linked with one of two chemical agents. Combinations of these two treatments were cultured with mouse fibroblast cells. Viability was assessed with flow cytometry, using propridium iodine to stain non-vital cells. Cell viability on treated tissue was compared to untreated tissue and control cell sets. Results indicate superior biocompatibility of one preparation, with viability high enough to warrant further studies. The next step will be implantation of the material into an animal model. With successful preparation, biological constructs can improve the host tissue response and reduce the need for revision surgery, thereby replacing conventional synthetic meshes for hernia repair.College of Engineering Undergraduate Research Optio

Influence of Vineyard Vegetational Borders on Western Grape Leafhopper (Erythroneura elegantula Osborn), its Egg Parasitoids (Anagrus spp.) and Generalist Insect Predators

Studies have shown that vegetational diversity in or around cropping systems can enhance naturalenemy abundance, although the impact on herbivores is less certain. We studied the influence of vineyardvegetational borders on density of the western grape leafhopper, Erythroneura elegantula, its majorparasitoids, Anagrus spp., and two generalist predators, Orius spp. and Leptothrips mali. Two studyvineyards had planted, perennial flowering hedgerows, one bordered a natural riparian zone, and onehad a sparse border of native trees. From April to September 2007, we counted leafhopper nymphs andadults of Anagrus spp., Orius spp. and L. mali within 10 m of the border, and at additional 20 m intervalsup to 90 m. At two sites with a diverse border, leafhopper density was stable nearest the border; at otherdistances leafhopper density decreased between the first and second generations. This effect was notseen at the sparse border site. Anagrus spp. density was enhanced at one site with a diverse border, butonly late season. There was no border effect on the generalist insect predators, by site or early vs. lateseason. Regression analysis showed a positive relationship between leafhopper and Anagrus spp. density,suggesting that the parasitoids were responding to higher leafhopper density. We conclude that, dependingon the nature of the border vegetation, there can be an effect on leafhopper nymphal density, but in thisstudy there is no evidence that it was due to natural enemies

Agarose entrapped gold nanoparticles for the crosslinking of collagen: A comparison study [abstract]

Abstract only availableAs one of the most common proteins found in the human body, collagen is generally regarded as biocompatible and has well-defined properties that make it ideal for biomedical applications. However, for purified forms of collagen, the overall biomechanical and biodegradation properties are inadequate for many of these applications. Efforts to strengthen the matrix and control biodegradation have traditionally focused on increasing the number of crosslinks formed between collagen molecules using both physical and chemical techniques. In addition to these techniques, glycosaminoglycans such as chondroitin sulfate are often added to collagen matrices to improve the flexibility and handling characteristics of the material, as well as to positively influence cellular adhesion and proliferation. Many of these techniques have been researched extensively; however, there is a lack of significant research in the area of nanomaterials and their potential to crosslink collagen. The purpose of these experiments was to determine if agarose-entrapped gold nanoparticles (AuNPs) could be utilized to crosslink collagen. Several formulations were prepared using different volumetric ratios of AuNPs to collagen, as well as duplicate formulations which also contained chondroitin sulfate. All collagen gels were allowed to crosslink at 37 ºC overnight and then fixed in paraformaldehyde and critical point dried in preparation for scanning electron microscopy. The resulting micrographs exhibited collagen matrices with a variety of structures and porosities. The matrices ranged from structures with large pores and AuNPs scattered along the collagen fibers to nearly solid sheets with clusters of AuNPs. Overall, the results supported the hypothesis that agarose entrapped AuNPs could be utilized to crosslink collagen. Future studies will focus on thorough characterization of the matrices to determine the optimal ratio of AuNPs to collagen.College of Engineering Undergraduate Research Optio

Alcohol and injuries in the accident and emergency department: a national perspective.

The purpose of this study was to examine the role of alcohol and injuries, with a specific focus in the A & E Departments in acute hospitals. The six hospitals were selected to achieve a wide geographic and demographic distribution across the country - Mater Misercordiae University Hospital in Dublin , Beaumont Hospital in Dublin, University College Hospital Galway, Sligo General Hospital, Letterkenny General Hospital and Waterford Regional Hospital. Data was collected using a standard 25 minute questionnaire, which included the type and cause of the presenting injury, drinking in the six hours prior to the injury, quantity and frequency of usual drinking habits, frequency of high consumption times during the last year, indicators of alcohol problems and alcohol dependency and demographic characteristics

Deep Sequencing of Three Loci Implicated in Large-Scale Genome-Wide Association Study Smoking Meta-Analyses

Genome-wide association study meta-analyses have robustly implicated three loci that affect susceptibility for smoking: CHRNA5\CHRNA3\CHRNB4, CHRNB3\CHRNA6 and EGLN2\CYP2A6. Functional follow-up studies of these loci are needed to provide insight into biological mechanisms. However, these efforts have been hampered by a lack of knowledge about the specific causal variant(s) involved. In this study, we prioritized variants in terms of the likelihood they account for the reported associations. We employed targeted capture of the CHRNA5\CHRNA3\CHRNB4, CHRNB3\CHRNA6, and EGLN2\CYP2A6 loci and flanking regions followed by next-generation deep sequencing (mean coverage 78×) to capture genomic variation in 363 individuals. We performed single locus tests to determine if any single variant accounts for the association, and examined if sets of (rare) variants that overlapped with biologically meaningful annotations account for the associations. In total, we investigated 963 variants, of which 71.1% were rare (minor allele frequency < 0.01), 6.02% were insertion/deletions, and 51.7% were catalogued in dbSNP141. The single variant results showed that no variant fully accounts for the association in any region. In the variant set results, CHRNB4 accounts for most of the signal with significant sets consisting of directly damaging variants. CHRNA6 explains most of the signal in the CHRNB3\CHRNA6 locus with significant sets indicating a regulatory role for CHRNA6. Significant sets in CYP2A6 involved directly damaging variants while the significant variant sets suggested a regulatory role for EGLN2. We found that multiple variants implicating multiple processes explain the signal. Some variants can be prioritized for functional follow-up. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: [email protected]

The impact of COVID-19 on rheumatology training—results from the COVID-19 Global Rheumatology Alliance trainee survey

Objective: The aim was to evaluate the impact of the coronavirus disease 2019 (COVID-19) pandemic on the clinical experiences, research opportunities and well-being of rheumatology trainees. / Methods: A voluntary, anonymous, Web-based survey was administered in English, Spanish or French from 19 August 2020 to 5 October 2020. Adult and paediatric rheumatology trainees were invited to participate via social media and email. Using multiple-choice questions and Likert scales, the perceptions of trainees regarding the impact of the COVID-19 pandemic on patient care and redeployment, learning and supervision, research and well-being were assessed. / Results: There were 302 respondents from 33 countries, with 83% in adult rheumatology training. An increase in non-rheumatology clinical work was reported by 45%, with 68% of these having been redeployed to COVID-19. Overall, trainees reported a negative impact on their learning opportunities during rheumatology training, including outpatient clinics (79%), inpatient consultations (59%), didactic teaching (55%), procedures (53%), teaching opportunities (52%) and ultrasonography (36%). Impacts on research experiences were reported by 46% of respondents, with 39% of these reporting that COVID-19 negatively affected their ability to continue their pre-pandemic research. Burnout and increases in stress were reported by 50% and 68%, respectively. Physical health was negatively impacted by training programme changes in 25% of respondents. / Conclusion: The COVID-19 pandemic has had a substantial impact on rheumatology training and trainee well-being. Our study highlights the extent of this impact on research opportunities and clinical care, which are highly relevant to future curriculum planning and the clinical learning environment

Survival and major neurodevelopmental impairment in extremely low gestational age newborns born 1990–2000: a retrospective cohort study

<p>Abstract</p> <p>Background</p> <p>It is important to determine if rates of survival and major neurodevelopmental impairment in extremely low gestational age newborns (ELGANs; infants born at 23–27 weeks gestation) are changing over time.</p> <p>Methods</p> <p>Study infants were born at 23 to 27 weeks of gestation without congenital anomalies at a tertiary medical center between July 1, 1990 and June 30, 2000, to mothers residing in a thirteen-county region in North Carolina. Outcomes at one year adjusted age were compared for two epochs of birth: epoch 1, July 1, 1990 to June 30, 1995; epoch 2, July 1, 1995 to June 30, 2000. Major neurodevelopmental impairment was defined as cerebral palsy, Bayley Scales of Infant Development Mental Developmental Index more than two standard deviations below the mean, or blindness.</p> <p>Results</p> <p>Survival of ELGANs, as a percentage of live births, was 67% [95% confidence interval: (61, 72)] in epoch 1 and 71% (65, 75) in epoch 2. Major neurodevelopmental impairment was present in 20% (15, 27) of survivors in epoch 1 and 14% (10, 20) in epoch 2. When adjusted for gestational age, survival increased [odds ratio 1.5 (1.0, 2.2), p = .03] and major neurodevelopmental impairment decreased [odds ratio 0.54 (0.31, 0.93), p = .02] from epoch 1 to epoch 2.</p> <p>Conclusion</p> <p>The probability of survival increased while that of major neurodevelopmental impairment decreased during the 1990's in this regionally based sample of ELGANs.</p