Impact of SARS-CoV-2 on training and mental well-being of surgical gynecological oncology trainees

Introduction: The SARS-CoV-2 global pandemic has caused a crisis disrupting health systems worldwide. While efforts are being made to determine the extent of the disruption, the impact on gynecological oncology trainees/training has not been explored. We conducted an international survey of the impact of SARS-CoV-2 on clinical practice, medical education, and mental well-being of surgical gynecological oncology trainees. Methods: In our cross-sectional study, a customized web-based survey was circulated to surgical gynecological oncology trainees from national/international organizations from May to November 2020. Validated questionnaires assessed mental well-being. The Wilcoxon rank-sum test and Fisher's exact test were used to analyse differences in means and proportions. Multiple linear regression was used to evaluate the effect of variables on psychological/mental well-being outcomes. Outcomes included clinical practice, medical education, anxiety and depression, distress, and mental well-being. Results: A total of 127 trainees from 34 countries responded. Of these, 52% (66/127) were from countries with national training programs (UK/USA/Netherlands/Canada/Australia) and 48% (61/127) from countries with no national training programs. Altogether, 28% (35/125) had suspected/confirmed COVID-19, 28% (35/125) experienced a fall in household income, 20% (18/90) were self-isolated from households, 45% (57/126) had to re-use personal protective equipment, and 22% (28/126) purchased their own. In total, 32.3% (41/127) of trainees (16.6% (11/66) from countries with a national training program vs 49.1% (30/61) from countries with no national training program, p=0.02) perceived they would require additional time to complete their training fellowship. The additional training time anticipated did not differ between trainees from countries with or without national training programs (p=0.11) or trainees at the beginning or end of their fellowship (p=0.12). Surgical exposure was reduced for 50% of trainees. Departmental teaching continued throughout the pandemic for 69% (87/126) of trainees, although at reduced frequency for 16.1% (14/87), and virtually for 88.5% (77/87). Trainees reporting adequate pastoral support (defined as allocation of a dedicated mentor/access to occupational health support services) had better mental well-being with lower levels of anxiety/depression (p=0.02) and distress (p<0.001). Trainees from countries with a national training program experienced higher levels of distress (p=0.01). Mean (SD) pre-pandemic mental well-being scores were significantly higher than post-pandemic scores (8.3 (1.6) vs 7 (1.8); p<0.01). Conclusion: SARS-CoV-2 has negatively impacted the surgical training, household income, and psychological/mental well-being of surgical gynecological oncology trainees. The overall clinical impact was worse for trainees in countries with no national training program than for those in countries with a national training program, although national training program trainees reported greater distress. COVID-19 sickness increased anxiety/depression. The recovery phase must focus on improving mental well-being and addressing lost training opportunities

Lipopolysaccharide does not alter small airway reactivity in mouse lung slices

The bacterial endotoxin, lipopolysaccharide (LPS) has been associated with occupational airway diseases with asthma-like symptoms and in acute exacerbations of COPD. The direct and indirect effects of LPS on small airway reactivity have not been fully elucidated. We tested the hypothesis that both in vitro and in vivo LPS treatment would increase contraction and impair relaxation of mouse small airways. Lung slices were prepared from naïve Balb/C mice and cultured in the absence or presence of LPS (10 µg/ml) for up to 48 h for measurement of TNFα levels in conditioned media. Alternatively, mice were challenged with PBS or LPS in vivo once a day for 4 days for preparation of lung slices or for harvest of lungs for Q-PCR analysis of gene expression of pro-inflammatory cytokines and receptors involved in airway contraction. Reactivity of small airways to contractile agonists, methacholine and serotonin, and bronchodilator agents, salbutamol, isoprenaline and rosiglitazone, were assessed using phase-contrast microscopy. In vitro LPS treatment of slices increased TNFα release 6-fold but did not alter contraction or relaxation to any agonists tested. In vivo LPS treatment increased lung gene expression of TNFα, IL-1β and ryanodine receptor isoform 2 more than 5-fold. However there were no changes in reactivity in lung slices from these mice, even when also incubated with LPS ex vivo. Despite evidence of LPS-induced inflammation, neither airway hyperresponsiveness or impaired dilator reactivity were evident. The increase in ryanodine receptor isoform 2, known to regulate calcium signaling in vascular smooth muscle, warrants investigation. Since LPS failed to elicit changes in small airway reactivity in mouse lung slices following in vitro or in vivo treatment, alternative approaches are required to define the potential contribution of this endotoxin to altered small airway reactivity in human lung diseases

Microfluidic Perfusion for Regulating Diffusible Signaling in Stem Cells

Background Autocrine & paracrine signaling are widespread both in vivo and in vitro, and are particularly important in embryonic stem cell (ESC) pluripotency and lineage commitment. Although autocrine signaling via fibroblast growth factor-4 (FGF4) is known to be required in mouse ESC (mESC) neuroectodermal specification, the question of whether FGF4 autocrine signaling is sufficient, or whether other soluble ligands are also involved in fate specification, is unknown. The spatially confined and closed-loop nature of diffusible signaling makes its experimental control challenging; current experimental approaches typically require prior knowledge of the factor/receptor in order to modulate the loop. A new approach explored in this work is to leverage transport phenomena at cellular resolution to downregulate overall diffusible signaling through the physical removal of cell-secreted ligands. Methodology/Principal Findings We develop a multiplex microfluidic platform to continuously remove cell-secreted (autocrine\paracrine) factors to downregulate diffusible signaling. By comparing cell growth and differentiation in side-by-side chambers with or without added cell-secreted factors, we isolate the effects of diffusible signaling from artifacts such as shear, nutrient depletion, and microsystem effects, and find that cell-secreted growth factor(s) are required during neuroectodermal specification. Then we induce FGF4 signaling in minimal chemically defined medium (N2B27) and inhibit FGF signaling in fully supplemented differentiation medium with cell-secreted factors to determine that the non-FGF cell-secreted factors are required to promote growth of differentiating mESCs. Conclusions/Significance Our results demonstrate for the first time that flow can downregulate autocrine\paracrine signaling and examine sufficiency of extracellular factors. We show that autocrine\paracrine signaling drives neuroectodermal commitment of mESCs through both FGF4-dependent and -independent pathways. Overall, by uncovering autocrine\paracrine processes previously hidden in conventional culture systems, our results establish microfluidic perfusion as a technique to study and manipulate diffusible signaling in cell systems.National Institutes of Health (U.S.) (NIH grant No. EB007278)Swiss National Science FoundationSwiss National Science Foundatio

Correlation of adrenomedullin gene expression in peripheral blood leukocytes with severity of ischemic stroke

Human adrenomedullin (ADM), a 52-amino acid peptide, belongs to the calcitonin/calcitonin gene-related peptide (CGRP)/amylin peptide family. ADM acts as a multifunctional regulatory peptide and is upregulated in response to hypoxia. Previous microarray studies have found increased ADM gene (ADM) expression in peripheral blood cells of patients with stroke, however, it is unknown if an increased ADM level is correlated with severity of human ischemic stroke. This study investigated ADM expression in peripheral blood leukocytes (PBL) of healthy controls and subjects at day 1, week 1 and week 3 postacute ischemic stroke using rtPCR methodology. We found that ADM expression was significantly upregulated on the first day of stroke compared to the healthy subjects and the disease controls; the levels remained elevated for up to week 3. Further, ADM expression at day 1 was correlated with stroke severity measured by the National Institute of Healthy Stroke Scale (NIHSS), the modified Barthel Index (mBI) and the modified Rankin Scale (mRS). This could indicate that ADM expression level is related to the severity of tissue damage. We suggest that increased ADM expression in PBL after acute ischemic stroke is most likely to indicate that these cells have been subjected to hypoxia and that the magnitude of expression is likely to be related to the volume of hypoxic tissue. Hypoxia can affect lymphocytes function and could affect the immune response to stroke. The correlation of ADM expression level with the measures of stroke severity implicates ADM - a potential blood bio-marker in studies of ischemic stroke

The Mitochondrial Ca(2+) Uniporter: Structure, Function, and Pharmacology.

Mitochondrial Ca(2+) uptake is crucial for an array of cellular functions while an imbalance can elicit cell death. In this chapter, we briefly reviewed the various modes of mitochondrial Ca(2+) uptake and our current understanding of mitochondrial Ca(2+) homeostasis in regards to cell physiology and pathophysiology. Further, this chapter focuses on the molecular identities, intracellular regulators as well as the pharmacology of mitochondrial Ca(2+) uniporter complex

Variation of Maximum Tree Height and Annual Shoot Growth of Smith Fir at Various Elevations in the Sygera Mountains, Southeastern Tibetan Plateau

Little is known about tree height and height growth (as annual shoot elongation of the apical part of vertical stems) of coniferous trees growing at various altitudes on the Tibetan Plateau, which provides a high-elevation natural platform for assessing tree growth performance in relation to future climate change. We here investigated the variation of maximum tree height and annual height increment of Smith fir (Abies georgei var. smithii) in seven forest plots (30 m×40 m) along two altitudinal transects between 3,800 m and 4,200/4,390 m above sea level (a.s.l.) in the Sygera Mountains, southeastern Tibetan Plateau. Four plots were located on north-facing slopes and three plots on southeast-facing slopes. At each site, annual shoot growth was obtained by measuring the distance between successive terminal bud scars along the main stem of 25 trees that were between 2 and 4 m high. Maximum/mean tree height and mean annual height increment of Smith fir decreased with increasing altitude up to the tree line, indicative of a stress gradient (the dominant temperature gradient) along the altitudinal transect. Above-average mean minimum summer (particularly July) temperatures affected height increment positively, whereas precipitation had no significant effect on shoot growth. The time series of annual height increments of Smith fir can be used for the reconstruction of past climate on the southeastern Tibetan Plateau. In addition, it can be expected that the rising summer temperatures observed in the recent past and anticipated for the future will enhance Smith fir's growth throughout its altitudinal distribution range

Fibroblast growth factor signalling controls nervous system patterning and pigment cell formation in Ciona intestinalis

During the development of the central nervous system (CNS), combinations of transcription factors and signalling molecules orchestrate patterning, specification and differentiation of neural cell types. In vertebrates, three types of melanin-containing pigment cells, exert a variety of functional roles including visual perception. Here we analysed the mechanisms underlying pigment cell specification within the CNS of a simple chordate, the ascidian Ciona intestinalis. Ciona tadpole larvae exhibit a basic chordate body plan characterized by a small number of neural cells. We employed lineage-specific transcription profiling to characterize the expression of genes downstream of fibroblast growth factor signalling, which govern pigment cell formation. We demonstrate that FGF signalling sequentially imposes a pigment cell identity at the expense of anterior neural fates. We identify FGF-dependent and pigment cell-specific factors, including the small GTPase, Rab32/38 and demonstrated its requirement for the pigmentation of larval sensory organs

Shikonin Increases Glucose Uptake in Skeletal Muscle Cells and Improves Plasma Glucose Levels in Diabetic Goto-Kakizaki Rats

Glucose is the most common substrate for energy metabolism. Despite the varying demands for glucose, the body needs to regulate its internal environment and maintain a constant and stable condition. Glucose homeostasis requires harmonized interaction between several tissues, achieving equilibrium between glucose output and uptake. In this thesis we aimed to investigate factors modulating glucose homeostasis in a rat model of type 2 diabetes, the Goto-Kakizaki (GK) rat. In addition, we investigated sex differences in hepatic carbohydrate and lipid metabolism in healthy rats. In Paper I, three-week but not three-day treatment with a Southeast Asian herb, Gynostemma pentaphyllum (GP), significantly reduced plasma glucose (PG) levels in GK rats. An intra-peritoneal glucose tolerance test (IPGTT) was significantly improved in GP-treated compared to placebo-treated group. In the GP treated rats, the glucose response in an intra-peritoneal pyruvate tolerance test was significantly lower, indicating decreased gluconeogenesis, and hepatic glucose output (HGO) was reduced. GP-treatment significantly reduced hepatic glycogen content, but not glycogen synthase activity. The study provides evidence that the GP extract exerted anti-diabetic effect in GK rats, reducing PG levels and HGO, suggesting that GP improves the hepatic insulin sensitivity by suppressing gluconeogenesis. In Paper II, shikonin, a naphthoquinone derived from the Chinese plant Lithospermum erythrorhizon, increased glucose uptake in L6 myotubes, but did not phosphorylate Akt. Furthermore we found no evidence for the involvement of AMP activated protein kinase (AMPK) in shikonin induced glucose uptake. Shikonin increased the intracellular levels of calcium in these cells and stimulated the translocation of GLUT4 from intracellular vesicles to the cell surface in L6 myotubes. In GK rats treated with shikonin once daily for 4 days, PG levels were significantly decreased. In an insulin sensitivity test, the absolute PG levels were significantly lower in the shikonin-treated rats. These findings suggest that shikonin increases glucose uptake in muscle cells via an insulin-independent pathway dependent on calcium. In Paper III, GK and control Wistar rats were injected daily for up to 4 weeks with either a non-hematopoietic erythropoietin analog ARA290 or with placebo. PG levels in GK but not Wistar rats were significantly lower in ARA290-treated compared to placebo. After 2 and 4 weeks, the IPGTT was significantly improved in ARA290 treated GK rats. In insulin and pyruvate tolerance tests, glucose responses were similar in ARA290 and placebo groups. In isolated GK rat islets, glucose-stimulated insulin release was two-fold higher and islet intracellular calcium concentrations in response to several secretagogues were significantly higher in ARA290-treated than in placebo-treated GK rats. These findings indicate that treatment with ARA290 significantly improved glucose tolerance in diabetic GK rats, most likely due to improvement of insulin release. In Paper IV, sex differences in hepatic carbohydrate and lipid metabolism were characterized in healthy rats. No sex-differences were observed regarding hepatic triglyceride content, fatty acid oxidation rates or insulin sensitivity. Male rats had higher ratios of insulin to glucagon levels, increased hepatic glycogen content, a lower degree of AMPK phosphorylation, a higher rate of glucose production and higher expression levels of gluconeogenic genes, as compared to female rats. A sex-dependent response to mild starvation was observed with males being more sensitive. In conclusion, sex-differences reflect a higher capacity of the healthy male rat liver to respond to increased energy demands. Key words: glucose homeostasis, type 2 diabetes, GK rats, L6 myotubes, hepatic glucose output, insulin sensitivity, sex differences

Structural insights into Ca2+-activated long-range allosteric channel gating of RyR1

Ryanodine receptors (RyRs) are a class of giant ion channels with molecular mass over 2.2 mega-Daltons. These channels mediate calcium signaling in a variety of cells. Since more than 80% of the RyR protein is folded into the cytoplasmic assembly and the remaining residues form the transmembrane domain, it has been hypothesized that the activation and regulation of RyR channels occur through an as yet uncharacterized long-range allosteric mechanism. Here we report the characterization of a Ca2+-activated open-state RyR1 structure by cryo-electron microscopy. The structure has an overall resolution of 4.9 angstrom and a resolution of 4.2 angstrom for the core region. In comparison with the previously determined apo/closed-state structure, we observed long-range allosteric gating of the channel upon Ca2+ activation. In-depth structural analyses elucidated a novel channel-gating mechanism and a novel ion selectivity mechanism of RyR1. Our work not only provides structural insights into the molecular mechanisms of channel gating and regulation of RyRs, but also sheds light on structural basis for channel-gating and ion selectivity mechanisms for the six-transmembrane-helix cation channel family.Strategic Priority Research Program of Chinese Academy of Sciences [XDB08030202]; National Basic Research Program (973 Program); Ministry of Science &amp; Technology of China [2012CB917200, 2014CB910700]; National Natural Science Foundation of China [31270768]; Ministry of Education of China (111 Program China)SCI(E)PubMed中国科技核心期刊(ISTIC)[email protected]; [email protected]

Uncovering the Importance of Selenium in Muscle Disease

A connection between selenium bioavailability and development of muscular disorders both in humans and livestock has been established for a long time. With the development of genomics, the function of several selenoproteins was shown to be involved in muscle activity, including SELENON, which was linked to an inherited form of myopathy. Development of animal models has helped to dissect the physiological dysfunction due to mutation in the SELENON gene; however the molecular activity remains elusive and only recent analysis using both in vivo and in vitro experiment provided hints toward its function in oxidative stress defence and calcium transport control. This review sets out to summarise most recent findings for the importance of selenium in muscle function and the contribution of this information to the design of strategies to cure the diseases