THYMOL TEMPERS As (III) AND Hg (II) CAUSED HYPERCONTRACTILITY BY SIMILAR PATHWAYS IN ISOLATED AORTIC AND TRACHEAL RINGS

Objective: Thymol is known to cause smooth muscle relaxation, possibly by inhibition of Ca2+influx, release or loss of its sensitivity. It is, however, also reported to be a strong antioxidant in several other systems. In this study, we investigate other possible pathways of thymol caused relaxation of aortic and tracheal segments by using specific blockers, and explore it as potential ameliorator of arsenic and mercury caused hyper contraction.Methods: Male Wistar rats were used in all experiments. Aorta/trachea was carefully removed, cleaned, and cut into 2-mm thick rings. Isometric contractions were measured using organ bath system. One-way analysis of variance (ANOVA) and Student's t-test were used for statistical analyses. P<0.05 was considered significant.Results: In pollutant unexposed aortic and tracheal segments, thymol is found to inhibit contractions through quenching of reactive oxygen species (ROS) in addition to its previously reported effects on Ca2+movements. Equal effectiveness in absence and presence of NG-nitro-L-arginine methyl ester (L-NAME) indicates that nitric oxide (NO) has no significant role in the thymol caused relaxation.Conclusion: In both muscle types, thymol is found to be an effective ameliorator of As (III) and Hg (II) caused hyper contraction, at low concentrations; it acts by inhibiting the Ca2+influx whereas at high concentration, it acts by blocking Ca2+influx and neutralizing ROS.Â

Effect of palm-sesame biodiesel fuels with alcoholic and nanoparticle additives on tribological characteristics of lubricating oil by four ball tribo-tester

Dilution of engine oil with unburned fuels alters its lubricity and tribological properties. In this research paper, SAE-40 lubricating oil samples were contaminated with known percentages (5%) of fuels (diesel, palm-sesame biodiesel blend (B30), B30 + ethanol, B30 + dimethyl carbonate, B30 + carbon nanotubes and, B30 + titanium oxide). The effect of all these fuels on wear and frictional characteristics of lubricating oil was determined by using a 4-ball tribo tester and wear types on worn surfaces were analyzed by using SEM. Lubricating oil diluted with B10 (commercial diesel) showed highest COF (42.95%) with severe abrasive and adhesive wear than mineral lubricant among other fuels. Lubricating oil diluted with palm-sesame biodiesel (B30 blend) with alcoholic additives showed comparatively less COF, less wear scar diameter and polishing wear due to presence of ester molecules. Lub + B30 + Eth exhibited increment in COF value (35.81%) compared to SAE-40 mineral lubricant. While lubricating oil contaminated with B30 with nanoparticles showed least frictional characteristics with abrasive wear. Lub + B30 + TiO2 showed least increment in COF value (13.78%) among all other contaminated fuels compared to SAE-40 mineral lubricant. It is concluded that nanoparticles in biodiesel blends (B30) helps in reducing degradation of lubricants than alcoholic fuel additives and commercial diesel. (C) 2021 THE AUTHORS. Published by Elsevier BV on behalf of Faculty of Engineering, Alexandria University

Gene Expression Signature of DMBA-Induced Hamster Buccal Pouch Carcinomas: Modulation by Chlorophyllin and Ellagic Acid

Chlorophyllin (CHL), a water-soluble, semi-synthetic derivative of chlorophyll and ellagic acid (EA), a naturally occurring polyphenolic compound in berries, grapes, and nuts have been reported to exert anticancer effects in various human cancer cell lines and in animal tumour models. The present study was undertaken to examine the mechanism underlying chemoprevention and changes in gene expression pattern induced by dietary supplementation of chlorophyllin and ellagic acid in the 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis model by whole genome profiling using pangenomic microarrays. In hamsters painted with DMBA, the expression of 1,700 genes was found to be altered significantly relative to control. Dietary supplementation of chlorophyllin and ellagic acid modulated the expression profiles of 104 and 37 genes respectively. Microarray analysis also revealed changes in the expression of TGFβ receptors, NF-κB, cyclin D1, and matrix metalloproteinases (MMPs) that may play a crucial role in the transformation of the normal buccal pouch to a malignant phenotype. This gene expression signature was altered on treatment with chlorophyllin and ellagic acid. Our study has also revealed patterns of gene expression signature specific for chlorophyllin and ellagic acid exposure. Thus dietary chlorophyllin and ellagic acid that can reverse gene expression signature associated with carcinogenesis are novel candidates for cancer prevention and therapy

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

<span style="font-size:14.0pt;line-height: 115%;font-family:"Times New Roman";mso-fareast-font-family:"Times New Roman"; color:black;mso-ansi-language:EN-IN;mso-fareast-language:EN-IN;mso-bidi-language: HI" lang="EN-IN">Effect of phosphocreatine on H⁺ extrusion, <i>p</i>H_i<i> </i>and dimorphism in <i>Candida albicans</i></span>

785-790<span style="font-size:14.0pt;line-height: 115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">Candida albicans <span style="font-size:14.0pt; line-height:115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">is an opportunistic pathogen. Its proliferation in human hosts is believed to be controlled by immunologic mechanisms. The plasma membrane of the fungus posseses an H+-ATPase (PM-ATPase) which actively extrudes protons to generate an electrochemical gradient which is used in co-transport of nutrients. This ATPase is associated with the growth, dimorphism and pathogenicity of the fungus. The physiological concentration of phosphocreatine (PCr) is 20-35 mM in skeletal muscles. H+-extrusion in Candida cells was strongly inhibited by PCr; 44% at 20mM and 69% at 40mM. H+extrusion was stimulated 6.2-fold in the presence of 10mM glucose. This glucose stimulated extrusion was inhibited significantly by PCr; 36% at 20mM and 53% at 40mM. The intracellular pH pattern of cells destined to differentiate was greatly altered in the presence of PCr. Evagination time for control cells was between 90-120 min. PCr, delayed dimorphism, reduced the population of cells differentiating to hyphae and also reduced the length of hyphae after each time interval. Only 60% differentiation was observed with 10mM  PCr and 40% for higher PCr concentration even after 210 min. Direct interaction of PM-ATPase and PCr has been demonstrated by difference spectrum measurement employing stopped flow spectrophotometer. It can be concluded that PCr may be playing a significant role in checking growth and pathogenesis of C. albicans.</span

Nutrient associated changes in plasma membrane H⁺-ATPase activity of permeabilized <i>Candida albicans </i>cells

241-244Nutrient stimulated H+ extrusion by cells and spheroplasts of Candida albicans and its underlying mechanism has been investigated. Glucose and glutamic acid stimulated extrusion by a factor of 6 and 1.4 respectively in cells, but had no effect on spheroplasts. Proline showed no H+ stimulation in cells, however, it stimulated spheroplasts 1.5 fold. ATPase activity of toluene-ethanoi-Triton-X-100 (TET) permeabilized cells decreased by 20% following exposure to glucose and proline and 30% following exposure to glutamic acid. Permeabilized spheroplasts of Candida albicans showed drastic reduction in ATPase activity by 40%, 70% and 85% following exposure to glucose, proline and glutamic acid respectively. Externally added F-actin fully restored activity in the case of permeabilized cells and partly with spheroplasts suggesting that ATPase interacts with other membrane proteins during nutrient stimulation of cells

Effect of nitric oxide on H⁺-efflux in presence of various nutrients in <i>Candida albicans</i>

86-90In the present study tentative link has been established between H+-efflux and effect of NO in presence of various nutrients (glucose, 2-deoxy-D-glucose, xylose, proline, glutamic acid and lysine) in C. albicans using sodium nitroprusside (SP) as a potent source of NO. It was observed that there was a decreasing trend in pH with time, in control, while SNP treated cells showed an initial decline in pH for 10-15 min, followed by an increase in pH up to 30 min. In presence of glucose there was an enhancement in H+-efflux by 9-fold whereas proline, glutamic acid and lysine showed enhancement by 3, 6 and 1.5- fold respectively. Similar trends in increase in pH after 15 min in SNP treated cells of Candida was observed in presence of all nutrients used. It was demonstrated for the first time that H+-ATPase of C. albicans was affected by NO

Effect of sodium nitroprusside on H⁺ -ATPase activity and ATP concentration in <i>Candida albicans</i>

873-879ATP hydrolysis by plasma membrane H+-ATPase from Candida albicans has been investigated in presence of nitric oxide and various nutrients (sugars and amino acids). Sodium nitroprusside (SNP) was used as nitric oxide donor. It was found that ATP concentration decreased in SNP treated cells which was more in presence of sugars like glucose, xylose and 2-deoxy-D-glucose and amino acids as compared to their respective controls. The activity of H+-ATPase from plasma membrane decreased by 70 % in SNP treated cells. Both in vivo and in vitro treatments of SNP showed almost similar effects of decrease in ATPase activity. Effect of SNP was more pronounced in presence of nutrients. Interestingly, it was observed that vanadate did not show any independent effect in presence of nitric oxide. Several workers have reported similar type of results with other P-type A TPases. For the first time, it was observed in the present study that in presence of nitric oxide, H+-ATPase activity decreased like other P-type ATPases. Our study indicated that NO had a significant effect on ATP synthesis and activity of H+- ATPase. In the presence of NO, the ATP concentration was decreased indicating it affected mitochondrial electron transport chain. It may be concluded that NO, not only affects (inhibit) mitochondrial electron transport chain but also interferes with H+- ATPase of plasma membrane by changing its conformation resulting in decreased activity