Reduced endothelial caveolin-1 underlies deficits in brain insulin signalling in type 2 diabetes.

Patients with type 2 diabetes exhibit severe impairments in insulin signalling in the brain and are five times more likely to develop Alzheimer's disease. However, what leads to these impairments is not fully understood. Here, we show reduced expression of endothelial cell caveolin-1 (Cav-1) in the db/db (Leprdb) mouse model of type 2 diabetes. This reduction correlated with alterations in insulin receptor expression and signalling in brain microvessels as well as brain parenchyma. These findings were recapitulated in the brains of endothelial cell-specific Cav-1 knock-out (Tie2Cre; Cav-1fl/fl) mice. Lack of Cav-1 in endothelial cells led to reduced response to insulin as well as reduced insulin uptake. Furthermore, we observed that Cav-1 was necessary for the stabilization of insulin receptors in lipid rafts. Interactome analysis revealed that insulin receptor interacts with Cav-1 and caveolae-associated proteins, insulin-degrading enzyme and the tight junction protein Zonula Occludence-1 in brain endothelial cells. Restoration of Cav-1 in Cav-1 knock-out brain endothelial cells rescued insulin receptor expression and localization. Overall, these results suggest that Cav-1 regulates insulin signalling and uptake by brain endothelial cells by modulating IR-α and IR-ß localization and function in lipid rafts. Furthermore, depletion of endothelial cell-specific Cav-1 and the resulting impairment in insulin transport leads to alteration in insulin signalling in the brain parenchyma of type 2 diabetics.

The impact of heat treatment on E. coli cell physiology in rich and minimal media considering oxidative secondary stress.

AIMS: This study investigates the cell physiology of thermally injured bacterial cells, with a specific focus on oxidative stress and the repair mechanisms associated with oxidative secondary stress. METHODS AND RESULTS: We explored the effect of heat treatment on the activity of two protective enzymes, levels of intracellular reactive oxygen species, and redox potential. The findings reveal that enzyme activity slightly increased after heat treatment, gradually returning to baseline levels during subculture. The response of Escherichia coli cells to heat treatment, as assessed by the level of superoxide radicals generated and redox potential, varied based on growth conditions, namely minimal and rich media. Notably, the viability of injured cells improved when antioxidants were added to agar media, even in the presence of metabolic inhibitors. CONCLUSIONS: These results suggest a complex system involved in repairing damage in heat-treated cells, particularly in rich media. While repairing membrane damage is crucial for cell regrowth and the electron transport system plays a critical role in the recovery process of injured cells under both tested conditions.

Evaluation of distinct modes of oxidative secondary injury generated in heat-treated cells of Escherichia coli with solid/liquid and complex/semi-synthetic media sets.

AIMS: To characterize and evaluate oxidative secondary injury generated in heat-treated Escherichia coli cells during recovery cultivation either on agar or in a broth of a semi-synthetic enriched M9 (EM9) medium and a complex Luria broth (LB) medium with different types of antioxidants. METHODS AND RESULTS: E. coli cells grown in the EM9 and LB broth were heated at 50°C in a buffer (pH 7.0). Heated cells were recovered on the same kind of agar medium as that used for growth, with or without different antioxidants. Although these antioxidants mostly protected the cells from oxidative secondary injury on the recovery media, sodium thiosulphate and sodium pyruvate were most protective on EM9 and LB agars, respectively. Determination of viability using the most probable number and growth delay analysis methods showed significant reductions in the protective effects of antioxidants in the EM9 and LB media. CONCLUSION: Oxidative secondary injury generated in heated E. coli cells was found to be qualitatively and quantitatively diverse under cellular and environmental conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results suggest that different modes of oxidation should be considered in viability determination and injured cell enumeration of heat-treated cells.

A Retrospective Cohort Analysis Comparing Analytic and Holistic Marking Rubrics in Medical Research Education.

OBJECTIVES: The use of analytic rubrics in assessing and grading students' performance has become more prominent among instructors due to its reliability and validity in ensuring consistency in student evaluation. However, there is limited evidence demonstrating the consistency of examiner judgments between analytic marking rubrics and holistic marking rubrics. METHODS: Therefore, we aimed to compare the consistency of marks given using holistic marking methods and analytic rubrics at an Australian university by analyzing the mean mark differences and number of adjudications between two rubric types as well as the inter-rater reliability between two assessors. We analyzed all scores for project manuscripts between 2016 and 2021 for Honours medical students. We compared the mean mark differences graded using the Kruskal-Wallis test and Welch t-test. We used chi-squared tests to compare the frequency of adjudications for each rubric type. We assessed interrater reliability by comparing the marks between the two examiners utilizing Pearson correlation. RESULTS: We found that analytic rubrics have lower mean mark differences and fewer adjudicators are required. We showed a strong positive association between the consistency of marks given and the use of analytic rubrics when compared to holistic marking. Pearson correlation showed a low but stronger correlation between marks awarded by the two assessors when analytic rubrics were used (r = 0.36), compared to holistic marking rubrics (r = 0.24). CONCLUSIONS: Our findings suggest that the use of analytic rubrics may increase the consistency and reliability between two independent examiners in marking medical students' work.

MICROSURGICAL REIMPLANTATION OUTCOMES FOR COMPLETE AND INCOMPLETE AMPUTATIONS OF DISTAL PHALANGES OF FINGERS.

Introduction: The intricate endeavor of replanting the distal phalanx of the finger remains a persistent challenge. In the pursuit of addressing this concern, microsurgical replantation procedures have been systematically examined for distal phalanx injuries encircling the distal interphalangeal (DIP) joint, conducted at the Orthopaedic Hospital situated in Ho Chi Minh City. Materials and Methods: This investigation encompassed a cohort of 31 patients, comprising individuals with 17 instances of complete and 21 instances of incomplete amputations of the distal phalanges. The subjects' ages spanned a range from 3 to 56 years. Results: The study divulged that eight fingers, involving four complete amputations and four incomplete amputations, did not achieve successful outcomes. In contrast, the remaining 30 fingers exhibited survival. A meticulous long-term follow-up of 17 fingers, extending over a period exceeding six months, unveiled commendable achievements encompassing satisfactory sensory recovery, cosmetic enhancement, and the resumption of pre-injury occupational activities by the patients. Discussion: Vein anastomosis was revealed as a notably challenging aspect of the surgical procedures. In scenarios where conventional vein suturing was rendered unfeasible, the innovative recourse of one-way drainage emerged as a viable alternative. Conclusion: The endeavor to replant the distal phalanx of the finger engenders a substantial level of complexity, particularly in the realm of venous anastomosis. This research underscores the need for focused efforts to address and surmount the intricacies associated with this aspect of surgical intervention.

"Excited When They See Their Name in Print": Research Outputs from an Australian Medical Program.

To promote evidence-based practice, medical schools offer students opportunities to undertake either elective or mandatory research projects. One important measure of the research program success is student publication rates. In 2006, UNSW Medicine implemented a mandatory research program in the 4th year of the undergraduate medical education program. This study identified student publication rates and explored student and supervisor experiences with the publication process. A retrospective audit of student publications from the 2007, 2011, and 2015 cohorts was undertaken to look at trends over time. Data collected included type of publication and study methodology. Semi-structured interviews were conducted with a sample of undergraduate students (n = 11), medical graduates (n = 14), and supervisors (n = 25) and analysed thematically. Student publication rates increased significantly (P = 0.002) from 28% in 2007 to 50.2% in 2015. Students able to negotiate their own project were more likely to publish (P = 0.02). Students reported personal affirmation and development of research skills from publishing their research findings, while graduates noted improved career opportunities. Supervisors expected students to publish but identified the time to publications and student motivation as key factors in achieving publication(s). A high publication rate is possible in a mandatory research program where students can negotiate their own topic and are given protected time. Publications happen after the research project has finished. Critical factors in successful publication include supervisor support and student motivation. Given the importance of the supervisor's role, staff development and faculty support to train and develop a body of skilled supervisors is required.

Genetic analysis of ORF5 porcine reproductive and respiratory syndrome virus isolated in Vietnam.

Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most economically important swine pathogens because it is highly infectious and causes economic losses due to decreased pig productivity. In this study, the 603 bp complete major envelope protein encoding gene (ORF5) of 32 field PRRSV isolates from Vietnam collected during 2008-2012 were sequenced and analyzed. Multiple nucleotide (nt) and deduced amino acid (aa) alignments of ORF5 were performed on the 32 isolates: the representative strains (European and North American genotypes), Chinese strains available in GenBank and vaccine strains licensed for use in Vietnam. The results showed 94.8-100.0% nt identity and 94.0-100% aa similarity among the 32 isolates. These isolates shared similarities with the prototype of the North American PRRSV strain (VR-2332; nt 87.8-89.3%, aa 87.5-90.0%), and Lelystat virus, the prototype of the European PRRSV strain (LV; nt 61.1-61.9%, aa 55.1-57.0%). There was greater similarity with QN07 (nt 96.5-98.5%, aa 96.0-99.0%) from the 2007 PRRS outbreak in QuangNam Province, CH-1a (nt 93.2-95.1%, 91.5-93.5%) isolated in China in 1995 and JXA1 (nt 96.5-98.6%, aa 95.0-98.0%), the highly pathogenic strain from China isolated in 2006. The Vietnamese isolates were more similar to JXA1-R (nt 96.5-98.6%, aa 95.0-98.0%), the strain used in Chinese vaccines, than to Ingelvac MLV/BSL-PS (nt 87.2-89.0%, aa 86.0-89.0%). Phylogenetic analysis showed that the 32 isolates were of the North American genotype and classified into sub-lineage 8.7. This sub-lineage contains highly pathogenic Chinese PRRSV strains. This study documents genetic variation in circulating PRRSV strains and could assist more effective use of PRRS vaccines in Vietnam.

BMDD: a novel approach for IoT platform (broker-less and microservice architecture, decentralized identity, and dynamic transmission messages).

Undeniably, Internet of Things (IoT) devices are gradually getting better over time; and IoT-based systems play a significant role in our lives. The pervasiveness of the new essential service models is expanding, and includes self-driving cars, smart homes, smart cities, as well as promoting the development of some traditional fields such as agriculture, healthcare, and transportation; the development of IoT devices has not shown any sign of cooling down. On the one hand, several studies are coming up with many scenarios for IoT platforms, but some critical issues related to performance, speed, power consumption, availability, security, and scalability are not yet fully resolved. On the other hand, IoT devices are manufactured and developed by different organizations and individuals; hence, there is no unified standard (uniformity of IoT devices), i.e., sending and receiving messages among them and between them and the upper layer (e.g., edge devices). To address these issues, this paper proposes an IoT Platform called BMDD (Broker-less and Microservice architecture, Decentralized identity, and Dynamic transmission messages) that has a combination of two architectural models, including broker-less and microservices, with cutting-edge technologies such as decentralized identity and dynamic message transmission. The main contributions of this article are five-fold, including: (i) proposing broker-less and microservice for the IoT platform which can reduce single failure point of brokering architecture, easy to scale out and improve failover; (ii) providing a decentralized authentication mechanism which is suitable for IoT devices attribute (i.e., mobility, distributed); (iii) applying the Role-Based Access Control (RBAC) model for the authorization process; (iv) exploiting the gRPC protocol combined with the Kafka message queue enhances transmission rates, transmission reliability, and reduces power consumption in comparison with MQTT protocol; and (v) developing a dynamic message transmission mechanism that helps users communicate with any device, regardless of the manufacturer, since it provides very high homogeneity.

Transgenic mice with increased astrocyte expression of IL-6 show altered effects of acute ethanol on synaptic function.

A growing body of evidence has revealed that resident cells of the central nervous system (CNS), and particularly the glial cells, comprise a neuroimmune system that serves a number of functions in the normal CNS and during adverse conditions. Cells of the neuroimmune system regulate CNS functions through the production of signaling factors, referred to as neuroimmune factors. Recent studies show that ethanol can activate cells of the neuroimmune system, resulting in the elevated production of neuroimmune factors, including the cytokine interleukin-6 (IL-6). Here we analyzed the consequences of this CNS action of ethanol using transgenic mice that express elevated levels of IL-6 through increased astrocyte expression (IL-6-tg) to model the increased IL-6 expression that occurs with ethanol use. Results show that increased IL-6 expression induces neuroadaptive changes that alter the effects of ethanol. In hippocampal slices from non-transgenic (non-tg) littermate control mice, synaptically evoked dendritic field excitatory postsynaptic potential (fEPSP) and somatic population spike (PS) at the Schaffer collateral to CA1 pyramidal neuron synapse were reduced by acute ethanol (20 or 60 mM). In contrast, acute ethanol enhanced the fEPSP and PS in hippocampal slices from IL-6 tg mice. Long-term synaptic plasticity of the fEPSP (i.e., LTP) showed the expected dose-dependent reduction by acute ethanol in non-tg hippocampal slices, whereas LTP in the IL-6 tg hippocampal slices was resistant to this depressive effect of acute ethanol. Consistent with altered effects of acute ethanol on synaptic function in the IL-6 tg mice, EEG recordings showed a higher level of CNS activity in the IL-6 tg mice than in the non-tg mice during the period of withdrawal from an acute high dose of ethanol. These results suggest a potential role for neuroadaptive effects of ethanol-induced astrocyte production of IL-6 as a mediator or modulator of the actions of ethanol on the CNS, including persistent changes in CNS function that contribute to cognitive dysfunction and the development of alcohol dependence.

Increased astrocyte expression of IL-6 or CCL2 in transgenic mice alters levels of hippocampal and cerebellar proteins.

Emerging research has identified that neuroimmune factors are produced by cells of the central nervous system (CNS) and play critical roles as regulators of CNS function, directors of neurodevelopment and responders to pathological processes. A wide range of neuroimmune factors are produced by CNS cells, primarily the glial cells, but the role of specific neuroimmune factors and their glial cell sources in CNS biology and pathology have yet to be fully elucidated. We have used transgenic mice that express elevated levels of a specific neuroimmune factor, the cytokine IL-6 or the chemokine CCL2, through genetic modification of astrocyte expression to identify targets of astrocyte produced IL-6 or CCL2 at the protein level. We found that in non-transgenic mice constitutive expression of IL-6 and CCL2 occurs in the two CNS regions studied, the hippocampus and cerebellum, as measured by ELISA. In the CCL2 transgenic mice elevated levels of CCL2 were evident in the hippocampus and cerebellum, whereas in the IL-6 transgenic mice, elevated levels of IL-6 were only evident in the cerebellum. Western blot analysis of the cellular and synaptic proteins in the hippocampus and cerebellum of the transgenic mice showed that the elevated levels of CCL2 or IL-6 resulted in alterations in the levels of specific proteins and that these actions differed for the two neuroimmune factors and for the two brain regions. These results are consistent with cell specific profiles of action for IL-6 and CCL2, actions that may be an important aspect of their respective roles in CNS physiology and pathophysiology.

CCL2-ethanol interactions and hippocampal synaptic protein expression in a transgenic mouse model.

Chronic exposure to ethanol produces a number of detrimental effects on behavior. Neuroadaptive changes in brain structure or function underlie these behavioral effects and may be transient or persistent in nature. Central to the functional changes are alterations in the biology of neuronal and glial cells of the brain. Recent data show that ethanol induces glial cells of the brain to produce elevated levels of neuroimmune factors including CCL2, a key innate immune chemokine. Depending on the conditions of ethanol exposure, the upregulated levels of CCL2 can be transient or persistent and outlast the period of ethanol exposure. Importantly, results indicate that the upregulated levels of CCL2 may lead to CCL2-ethanol interactions that mediate or regulate the effects of ethanol on the brain. Glial cells are in close association with neurons and regulate many neuronal functions. Therefore, effects of ethanol on glial cells may underlie some of the effects of ethanol on neurons. To investigate this possibility, we are studying effects of chronic ethanol on hippocampal synaptic function in a transgenic mouse model that expresses elevated levels of CCL2 in the brain through enhanced glial expression, a situation know to occur in alcoholics. Both CCL2 and ethanol have been reported to alter synaptic function in the hippocampus. In the current study, we determined if interactions are evident between CCL2 and ethanol at the level of hippocampal synaptic proteins. Two ethanol exposure paradigms were used; the first involved ethanol exposure by drinking and the second involved ethanol exposure in a paradigm that combines drinking plus ethanol vapor. The first paradigm does not produce dependence on ethanol, whereas the second paradigm is commonly used to produce ethanol dependence. Results show modest effects of both ethanol exposure paradigms on the level of synaptic proteins in the hippocampus of CCL2 transgenic mice compared with their non-transgenic littermate controls, consistent with ethanol-CCL2 interactions. No evidence of toxic effects of CCL2 or CCL2-ethanol interactions was observed. Taken together, these results support the idea that ethanol induced astrocyte production of CCL2 can result in neuroadaptive changes that interact with the actions of ethanol.