A fundamental question in molecular evolution is how protein functional differentiation alters the ability of cells and organisms to cope with stress and survive. To answer this question we used two paralogous Hsp70s from mouse and explored whether these highly similar cytosolic molecular chaperones, which apart their temporal expression have been considered functionally interchangeable, are differentiated with respect to their lipid-binding function. We demonstrate that the two proteins bind to diverse lipids with different affinities and therefore are functionally specialized. The observed lipid-binding patterns may be related with the ability of both Hsp70s to induce cell death by binding to a particular plasma-membrane lipid, and the potential of only one of them to promote cell survival by binding to a specific lysosomal-membrane lipid. These observations reveal that two seemingly identical proteins differentially modulate cellular adaptation and survival by having acquired specialized functions via sequence divergence. Therefore, this study provides an evolutionary paradigm, where promiscuity, specificity, sub- and neo-functionalization orchestrate one of the most conserved systems in nature, the cellular stress-response.

Shigella dysenteriae and Shigella flexneri are the causative agents of gastric infections in human. These bacteria have been known as a causative agent of food poisoning in human. The present study was carried out in order to isolate Shigella species and detect S. dysenteriae and S. flexneri in meat and meat product samples presented in Isfahan province, as well as to study the antibiotic resistance properties of isolates. In total, 80 bovine meat samples, 50 hamburgers, 50 mouthful roasts, 40 sausages and 40 salami from various brands and samples of meat, fish and final products of various factories were collected and analyzed. Frequency of Shigella species in bovine meat, hamburger, mouthful roast, sausage and salami were 8.75, 6, 4, 0 and 2.5%, respectively. In German sausage factories, the distribution of Shigella in meat, farsh and final product were 40, 10 and 10%. Meat products of A brand had the highest incidence. Frequency of Shigella species in chicken paste samples of A, B and C factories were 28.57, 20 and 0%, respectively. Shigella species had the highest levels of antibiotic resistance against gentamicin (100%), tetracycline (92.30%) and ampicillin (84.61%). Observing of sanitary principles in abattoirs, butchers and meat products factories can reduce incidence of Shigella species. Application of simple disk diffusion method can reduce the levels of antibiotic resistance. PRACTICAL APPLICATIONSObserving of sanitary principles in abattoirs, butchers and meat products factories can reduce incidence of Shigella species. Application of simple disk diffusion method can reduce the levels of antibiotic resistance.

Introduction: Alopecia areata (AA) is a common non-scaring hair loss disease. Genetic susceptibility and environmental factors can develop the disease. Objectives: We investigated the association between AA and ABO and Rh blood groups. Methods: This cross-sectional study was done on 200 patients with AA and 200 healthy controls (HCs) between March 2021 and September 2021. Results: The prevalence of blood groups O, A, B, and AB in patients with AA was 30%, 30.5%, 10.5%, and 29%, respectively. A significant difference was detected between the two groups in the frequency of the ABO and ABO*Rh blood groups (p-value < 0.05). Compared to the HCs, the prevalence of the AB and AB+ blood group was higher in AA patients. No significant relationship was detected between sex, BMI, duration of disease, age at onset, severity of alopecia tool (SALT) score, hair loss pattern, and nail involvement with ABO and Rh blood groups (p-value > 0.05). Conclusion: In conclusion, the highest difference was related to the AB+ blood group, so compared to HCs, the AB+ blood group frequency was higher in patients with AA. However, more studies with larger sample sizes on different ethnicities should be performed to verify the results of this study.