Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

Applying Transformer Insulation Using Weibull Extended Distribution Based on Progressive Censoring Scheme

In this paper, the Weibull extension distribution parameters are estimated under a progressive type-II censoring scheme with random removal. The parameters of the model are estimated using the maximum likelihood method, maximum product spacing, and Bayesian estimation methods. In classical estimation (maximum likelihood method and maximum product spacing), we did use the Newton–Raphson algorithm. The Bayesian estimation is done using the Metropolis–Hastings algorithm based on the square error loss function. The proposed estimation methods are compared using Monte Carlo simulations under a progressive type-II censoring scheme. An empirical study using a real data set of transformer insulation and a simulation study is performed to validate the introduced methods of inference. Based on the result of our study, it can be concluded that the Bayesian method outperforms the maximum likelihood and maximum product-spacing methods for estimating the Weibull extension parameters under a progressive type-II censoring scheme in both simulation and empirical studies

Bayesian Inferential Approaches and Bootstrap for the Reliability and Hazard Rate Functions under Progressive First-Failure Censoring for Coronavirus Data from Asymmetric Model

This paper deals with the estimation of the parameters for asymmetric distribution and some lifetime indices such as reliability and hazard rate functions based on progressive first-failure censoring. Maximum likelihood, bootstrap and Bayesian approaches of the distribution parameters and reliability characteristics are investigated. Furthermore, the approximate confidence intervals and highest posterior density credible intervals of the parameters are constructed based on the asymptotic distribution of the maximum likelihood estimators and Markov chain Monte Carlo technique, respectively. In addition, the delta method is implemented to obtain the variances of the reliability and hazard functions. Moreover, we apply two methods of bootstrap to construct the confidence intervals. The Bayes inference based on the squared error and LINEX loss functions is obtained. Extensive simulation studies are conducted to evaluate the behavior of the proposed methods. Finally, a real data set of the COVID-19 mortality rate is analyzed to illustrate the estimation methods developed here

Trials for Replacing Antibiotics Used in Production of Tissue Culture Vaccines by Natural Antibacterial and Antifungal Extracts

The continuous use of antibiotics for tissue culture adapted vaccines production has led to the increase in the bacterial resistance to these antibiotics. This study aims to evaluate the antimicrobial potential of thyme (Thymus vulgaris) and clove (Syzygium aromaticum) on bacterial and fungal contamination, in the production of tissue culture vaccines. The active agents in each plant were extracted by the conventional extraction technique using ethanol and water as solvents followed by concentration (steam distillation and boiling). The antimicrobial activities of different solvent extracts were determined in well agar diffusion technique using Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Candida albicans as model for gram positive, gram negative and fungal contamination, respectively. The cytotoxic effects of the different solvent extracts were tested on VERO and MDBK cell culture. The obtained results indicated that water and ethanolic extracts from thyme and clove plants showed significant antimicrobial activities (P < 0.05) as they could inhibit the growth of E. coli, S. aureus and Candida albicans. Ethanolic extract of thyme had the maximum zone of inhibition against E. coli (2.40±0.20) and Candida albicans (3.07±0.3), and the lowest inhibition zone against S. aureus (1.53±0.23), whereas the thyme water extract didn’t show any antimicrobial activity. The ethanolic extract of clove showed the greatest zone of inhibition against Candida albicans (2.63±0.2), E. coli (2.63±0.2), while the lowest was against S. aureus (1.87±0.3). Water extract of clove showed the greatest zone of inhibition against E. coli and S. aureus (1.93±0.4, and 2.47±0.1), respectively and 0.97±0.1 against Candida albicans. The ethanolic extracts of thyme and clove showed changes in the cell wall until concentration 1 mg/ml for clove and 10 µg/ml for thyme on VERO cells; while the cytotoxic effect on MDBK cells was observed till the concentration of 100 µg/ml for clove and thyme water extracts. In conclusion, the antimicrobial potential of clove  water extract on bacterial and fungal contaminant could replace antibiotics in the production of tissue culture vaccines at a concentration of 10 µg/ml

Exosomes Derived from BM-MSCs Mitigate the Development of Chronic Kidney Damage Post-Menopause via Interfering with Fibrosis and Apoptosis

The rate of chronic kidney disease (CKD) is increasing globally, and it is caused by continuous damage to kidney tissue. With time the renal damage becomes irreversible, leading to CKD development. In females, post-menopause lack of estrogen supply has been described as a risk factor for CKD development, and studies targeting post-menopause CKD are scarce. In the present study, we used exosomes isolated from bone marrow mesenchymal stem/stromal cells (BM-MSCs) to test their therapeutic potential against the development of CKD. At first, the menopause model was achieved by surgical bilateral ovariectomy in female albino rats. After that, 100 µg of exosomes was given to ovariectomized rats, and the study continued for 2 months. Changes in urine volume, urine protein content, kidney function biochemical parameters (creatinine and BUN), kidney antioxidant parameters (SOD, GPx and CAT), histological changes, immunohistochemical levels of caspase 3, and the gene expression of NGAL (related to kidney damage), TGFβ1 and αSMA (related to fibrosis and EMT), and caspase 3 (related to apoptosis) were studied. After the ovariectomy, the occurrence of CKD was confirmed in the rats by the drastic reduction of serum estrogen and progesterone levels, reduced urine output, increased urinary protein excretion, elevated serum creatinine and BUN, reduced GPx SOD, and CAT in kidney tissue, degenerative and fibrotic lesions in the histopathological examination, higher immunohistochemical expression of caspase 3 and increased expression of all studied genes. After exosomes administration, the entire chronic inflammatory picture in the kidney was corrected, and a near-normal kidney structure and function were attained. This study shows for the first time that BM-MSCs exosomes are potent for reducing apoptosis and fibrosis levels and, thus, can reduce the chronic damage of the kidneys in females that are in their menopause period. Therefore, MSCs-derived exosomes should be considered a valuable therapy for preserving postmenopausal kidney structure and function and, subsequently, could improve the quality of females’ life during menopause

Ameliorative Effects of Aspergillus awamori against the Initiation of Hepatocarcinogenesis Induced by Diethylnitrosamine in a Rat Model: Regulation of Cyp19 and p53 Gene Expression

Hepatocellular carcinoma (HCC) is the most common cancer in humans. Despite advances in its treatment, liver cancer remains one of the most difficult cancers to treat. This study aimed to investigate the ameliorative action and potential mechanism of Aspergillus awamori (ASP) administration against the initiation process of liver carcinogenesis induced by diethylnitrosamine (DEN) in male Wistar rats. Seventy-two male rats were divided equally into eight groups as follows, Group 1: untreated control; Group 2: DEN (200 mg/kg bw) intra-peritoneally for the initiation of HCC; Groups 3–5: DEN + ASP at a dose of 1, 0.5, and 0.25 mg/kg bw and groups 6–8: ASP at a dose of 1, 0.5, and 0.25 mg/kg bw. Supplementation of A. awamori significantly lightened the adverse impacts induced by DEN via restoring the leukogram to normal, lowering the elevated serum aspartate aminotransferase (AST), alanine transaminase (ALT), and γ-glutamyl transferase (GGT), and alkaline phosphatase (ALP). Furthermore, it enhanced the hepatic antioxidant capacity through increasing the reduced glutathione (GSH) level and catalase (CAT) activity with a marked reduction in malondialdehyde (MDA) level. In addition, it decreased the positive GST-P foci. Likewise, a significant alteration of DEN-associated hepatocarcinogenesis occurred through inhibiting cytochrome P450 (Cyp19) and activating p53 gene expression. In conclusion, supplementation of A. awamori counteracts the negative effects of DEN, inhibits the early development of GST-P-positive foci and could be used as a new alternative strategy for its chemo-preventive effect in liver cancer. To the best of our knowledge, the present study is the first to report the hepato-protective effect of A. awamori in induced hepatocarcinogenesis