Systematic review of robotic ventral hernia repair with meta-analysis.

BACKGROUND: Despite being one of the most common operations performed by general surgeons, there is a lack of consensus regarding the recommended approach for ventral hernia repair (VHR). Recent times have seen the rapid development of new techniques, such as robotic ventral hernia repair (RVHR). This systematic review and meta-analysis aims to evaluate the currently available evidence relating to RVHR, in comparison to open VHR (OVHR) and laparoscopic VHR (LVHR). METHODS: A systematic search of the following databases was conducted: PubMed, Embase, Scopus and Web of Science. A meta-analysis was performed for the outcomes of length of stay (LOS), recurrence, operative time, intraoperative complications, wound complications, 30-day readmission, 30-day reoperation, mortality and costs. RESULTS: A total of 39 studies met inclusion criteria. Overall, RVHR reduced LOS, intra-operative complications, wound complications and readmission compared to OVHR. Compared to LVHR, RVHR was associated with increased operative time and costs, with comparable clinical outcomes. CONCLUSION: There is currently a lack of robust evidence to support the robotic approach in VHR. It does not demonstrate major benefits in comparison to LVHR, which is more affordable and accessible. Strong quality, long-term data is required to help with establishing a gold standard approach in VHR.

Measuring undergraduates' understanding of the culture of scientific research as an outcome variable in research on CUREs.

Researchers who work on course-based undergraduate research experiences (CUREs) and issues related to science, technology, engineering, and math (STEM) retention have begun exploring changes in student thinking about what it means to be a scientist. To support this effort, we developed rubrics to score answers to three open-response prompts: What does it mean to think like a scientist? What does it mean to do science? and Did you do real research in your coursename labs? The rubric development process was iterative and was based on input from the literature, experienced researchers, and early-career undergraduates. A post hoc analysis showed that the rubric elements map to 27 of 31 statements in the Culture of Scientific Research (CSR) framework, suggesting that scored responses to the three prompts can assess how well students understand what being a science professional entails. Scores on responses from over 400 students who were starting an introductory biology course for majors furnish baseline data from the rubrics and suggest that (i) undergraduates at this level have, as expected, a novice-level understanding of CSR, and (ii) level of understanding in novice students does not vary as a function of demography or academic preparation. Researchers and instructors are encouraged to add CSR to their list of learning objectives for CUREs and consider assessing it using the rubrics provided here.

Differentiation of stem cell-derived pancreatic progenitors into insulin-secreting islet clusters in a multiwell-based static 3D culture system.

Orbital shaker-based suspension culture systems have been in widespread use for differentiating human pluripotent stem cell (hPSC)-derived pancreatic progenitors toward islet-like clusters during endocrine induction stages. However, reproducibility between experiments is hampered by variable degrees of cell loss in shaking cultures, which contributes to variable differentiation efficiencies. Here, we describe a 96-well-based static suspension culture method for differentiation of pancreatic progenitors into hPSC-islets. Compared with shaking culture, this static 3D culture system induces similar islet gene expression profiles during differentiation processes but significantly reduces cell loss and improves cell viability of endocrine clusters. This static culture method results in more reproducible and efficient generation of glucose-responsive, insulin-secreting hPSC-islets. The successful differentiation and well-to-well consistency in 96-well plates also provides a proof of principle that the static 3D culture system can serve as a platform for small-scale compound screening experiments as well as facilitating further protocol development.

A CURE on the Evolution of Antibiotic Resistance in Escherichia coli Improves Student Conceptual Understanding.

We developed labs on the evolution of antibiotic resistance to assess the costs and benefits of replacing traditional laboratory exercises in an introductory biology course for majors with a course-based undergraduate research experience (CURE). To assess whether participating in the CURE imposed a cost in terms of exam performance, we implemented a quasi-experiment in which four lab sections in the same term of the same course did the CURE labs, while all other students did traditional labs. To assess whether participating in the CURE impacted other aspects of student learning, we implemented a second quasi-experiment in which all students either did traditional labs over a two-quarter sequence or did CURE labs over a two-quarter sequence. Data from the first experiment showed minimal impact on CURE students' exam scores, while data from the second experiment showed that CURE students demonstrated a better understanding of the culture of scientific research and a more expert-like understanding of evolution by natural selection. We did not find disproportionate costs or benefits for CURE students from groups that are minoritized in science, technology, engineering, and mathematics.

Colonoscopy quality of GP endoscopists in three rural hospitals in Queensland, Australia.

BACKGROUND AND OBJECTIVES: Rural general practitioners (GPs) are responsible for delivering primary and secondary care to rural populations in Australia. There is limited literature investigating the performance of GP endoscopists. The aim of this study was to investigate the colonoscopy performance of three GP endoscopists in rural Queensland against current Australian quality indicator (QI) standards. METHOD: A cross sectional study investigated eligible colonoscopies between January 2018 and February 2021 by three GP endoscopists in three rural hospitals in Queensland, Australia. RESULTS: A total of 1674 colonoscopies were investigated. The GP endoscopists demonstrated high QI performance, above the recommended benchmarks. Caecal intubation rate, adenoma detection rate, sessile serrated adenoma/polyp detection rate and clinically significant serrated polyp detection rate were 97.9%, 49.5%, 16% and 14.1% respectively. The major colonoscopy-related complications rate was 0.06%. DISCUSSION: Rural GP endoscopists potentially can deliver safe, high-quality colonoscopy services for rural communities and can have an integral part in facilitating colorectal cancer prevention and treatment in rural communities.

A fine balance of hydrophobic-electrostatic communication pathways in a pH-switching protein.

Allostery is the phenomenon of coupling between distal binding sites in a protein. Such coupling is at the crux of protein function and regulation in a myriad of scenarios, yet determining the molecular mechanisms of coupling networks in proteins remains a major challenge. Here, we report mechanisms governing pH-dependent myristoyl switching in monomeric hisactophilin, whereby the myristoyl moves between a sequestered state, i.e., buried within the core of the protein, to an accessible state, in which the myristoyl has increased accessibility for membrane binding. Measurements of the pH and temperature dependence of amide chemical shifts reveal protein local structural stability and conformational heterogeneity that accompany switching. An analysis of these measurements using a thermodynamic cycle framework shows that myristoyl-proton coupling at the single-residue level exists in a fine balance and extends throughout the protein. Strikingly, small changes in the stereochemistry or size of core and surface hydrophobic residues by point mutations readily break, restore, or tune myristoyl switch energetics. Synthesizing the experimental results with those of molecular dynamics simulations illuminates atomistic details of coupling throughout the protein, featuring a large network of hydrophobic interactions that work in concert with key electrostatic interactions. The simulations were critical for discerning which of the many ionizable residues in hisactophilin are important for switching and identifying the contributions of nonnative interactions in switching. The strategy of using temperature-dependent NMR presented here offers a powerful, widely applicable way to elucidate the molecular mechanisms of allostery in proteins at high resolution.

In vivo Imaging of Calcium Activities from Pancreatic ß-cells in Zebrafish Embryos Using Spinning-disc Confocal and Two-photon Light-sheet Microscopy.

Visualizing the function of pancreatic ß-cells in vivo has been a long-sought goal for ß-cell researchers. Unlike imaging of ß-cells in mammalian species with conventional positron emission tomography and single-photon emission computed tomography, which only provides limited spatial-temporal resolution, transparent zebrafish embryos are a unique model that allows high-resolution fluorescent imaging of ß-cells in their native physiological microenvironment in vivo. Here, we detail a protocol for real-time visualization of individual ß-cell function in vivo in a non-invasive manner, through combination of a novel transgenic zebrafish reporter line Tg (ins:Rcamp1.07) with both a commercial spinning-disc confocal microscope and an in-house developed super-resolution microscope (2P3A-DSLM). The protocol described here allows for the longitudinal monitoring of dynamic calcium activities from heterogeneous ß-cells in early developing zebrafish embryos and is readily adaptable for use in imaging other important processes in islet biology, as well as screening new compounds that can promote ß-cell function or maturation using a living whole organism system.

Active learning narrows achievement gaps for underrepresented students in undergraduate science, technology, engineering, and math.

We tested the hypothesis that underrepresented students in active-learning classrooms experience narrower achievement gaps than underrepresented students in traditional lecturing classrooms, averaged across all science, technology, engineering, and mathematics (STEM) fields and courses. We conducted a comprehensive search for both published and unpublished studies that compared the performance of underrepresented students to their overrepresented classmates in active-learning and traditional-lecturing treatments. This search resulted in data on student examination scores from 15 studies (9,238 total students) and data on student failure rates from 26 studies (44,606 total students). Bayesian regression analyses showed that on average, active learning reduced achievement gaps in examination scores by 33% and narrowed gaps in passing rates by 45%. The reported proportion of time that students spend on in-class activities was important, as only classes that implemented high-intensity active learning narrowed achievement gaps. Sensitivity analyses showed that the conclusions are robust to sampling bias and other issues. To explain the extensive variation in efficacy observed among studies, we propose the heads-and-hearts hypothesis, which holds that meaningful reductions in achievement gaps only occur when course designs combine deliberate practice with inclusive teaching. Our results support calls to replace traditional lecturing with evidence-based, active-learning course designs across the STEM disciplines and suggest that innovations in instructional strategies can increase equity in higher education.

Triazole Substitution of a Labile Amide Bond Stabilizes Pantothenamides and Improves Their Antiplasmodial Potency.

The biosynthesis of coenzyme A (CoA) from pantothenate and the utilization of CoA in essential biochemical pathways represent promising antimalarial drug targets. Pantothenamides, amide derivatives of pantothenate, have potential as antimalarials, but a serum enzyme called pantetheinase degrades pantothenamides, rendering them inactive in vivo In this study, we characterize a series of 19 compounds that mimic pantothenamides with a stable triazole group instead of the labile amide. Two of these pantothenamides are active against the intraerythrocytic stage parasite with 50% inhibitory concentrations (IC50s) of ∼50 nM, and three others have submicromolar IC50s. We show that the compounds target CoA biosynthesis and/or utilization. We investigated one of the compounds for its ability to interact with the Plasmodium falciparum pantothenate kinase, the first enzyme involved in the conversion of pantothenate to CoA, and show that the compound inhibits the phosphorylation of [14C]pantothenate by the P. falciparum pantothenate kinase, but the inhibition does not correlate with antiplasmodial activity. Furthermore, the compounds are not toxic to human cells and, importantly, are not degraded by pantetheinase.

Stereochemical modification of geminal dialkyl substituents on pantothenamides alters antimicrobial activity.

Pantothenamides are N-substituted pantothenate derivatives which are known to exert antimicrobial activity through interference with coenzyme A (CoA) biosynthesis or downstream CoA-utilizing proteins. A previous report has shown that replacement of the ProR methyl group of the benchmark N-pentylpantothenamide with an allyl group (R-anti configuration) yielded one of the most potent antibacterial pantothenamides reported so far (MIC of 3.2 µM for both sensitive and resistant Staphylococcus aureus). We describe herein a synthetic route for accessing the corresponding R-syn diastereomer using a key diastereoselective reduction with Baker's yeast, and report on the scope of this reaction for modified systems. Interestingly, whilst the R-anti diastereomer is the only one to show antibacterial activity, the R-syn isomer proved to be significantly more potent against the malaria parasite (IC50 of 2.4±0.2 µM). Our research underlines the striking influence that stereochemistry has on the biological activity of pantothenamides, and may find utility in the study of various CoA-utilizing systems.

Context-dependent role of ATG4B as target for autophagy inhibition in prostate cancer therapy.

ATG4B belongs to the autophagin family of cysteine proteases required for autophagy, an emerging target of cancer therapy. Developing pharmacological ATG4B inhibitors is a very active area of research. However, detailed studies on the role of ATG4B during anticancer therapy are lacking. By analyzing PC-3 and C4-2 prostate cancer cells overexpressing dominant negative ATG4B(C74A)in vitro and in vivo, we show that the effects of ATG4B(C74A) are cell type, treatment, and context-dependent. ATG4B(C74A) expression can either amplify the effects of cytotoxic therapies or contribute to treatment resistance. Thus, the successful clinical application of ATG4B inhibitors will depend on finding predictive markers of response.

miRNA-95 mediates radioresistance in tumors by targeting the sphingolipid phosphatase SGPP1.

Radiation resistance poses a major clinical challenge in cancer treatment, but little is known about how microRNA (miR) may regulate this phenomenon. In this study, we used next-generation sequencing to perform an unbiased comparison of miR expression in PC3 prostate cancer cells rendered resistant to fractionated radiation treatment. One miR candidate found to be upregulated by ionizing radiation was miR-95, the enforced expression of which promoted radiation resistance in a variety of cancer cells. miR-95 overexpression recapitulated an aggressive phenotype including increased cellular proliferation, deregulated G2-M checkpoint following ionizing radiation, and increased invasive potential. Using combined in silico prediction and microarray expression analyses, we identified and validated the sphingolipid phosphatase SGPP1, an antagonist of sphingosine-1-phosphate signaling, as a target of miR-95 that promotes radiation resistance. Consistent with this finding, cell treatment with FTY720, a clinically approved small molecule inhibitor of S1P signaling, sensitized miR-95 overexpressing cells to radiation treatment. In vivo assays extended the significance of these results, showing that miR-95 overexpression increased tumor growth and resistance to radiation treatment in tumor xenografts. Furthermore, reduced tumor necrosis and increased cellular proliferation were seen after radiation treatment of miR-95 overexpressing tumors compared with control tumors. Finally, miR-95 expression was increased in human prostate and breast cancer specimens compared with normal tissue. Together, our work reveals miR-95 expression as a critical determinant of radiation resistance in cancer cells.