Gene, Cell and Tissue
Volume:8 Issue: 2, Apr 2021

 Staphylococcus aureus is a problematic infectious agent in hospitals as well as in the community. Nasal carriage of healthcare workers (HCWs) and sometimes patients are an important source for transmitting this bacterium to vulnerable individuals.

 The present study aimed to investigate the frequency of nasal carriage of S. aureus and the antimicrobial susceptibility pattern of this organism isolated from HCWs and patients at Shahid Mohammadi Hospital in Bandar Abbas, South of Iran.

 This cross-sectional study was conducted from November 2017 to December 2018. A total of 400 nasal swabs were taken from HCWs and patients to investigate the presence of S. aureus. An antimicrobial susceptibility pattern was carried out using the disc diffusion method according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Methicillin resistance was determined using cefoxitin disc diffusion and PCR for mecA gene. Agar dilution was performed to determine MIC of vancomycin and mupirocin.

 Of 130 HCWs, 11 (8.5%) subjects were nasal carriers, of which 5 (45.5%) harbored methicillin-resistant Staphylococcus aureus (MRSA). Of 270 patients, 21 (7.8%) patients were nasal carriers, of whom 9 (42.9%) patients were MRSA carriers. Linezolid and vancomycin were the most effective agents, and 100% of isolates were susceptible to these agents. Furthermore, high-level mupirocin-resistant S. aureus (HLMuRSA) was observed in 6.3% of the isolates.

 Our findings demonstrate that the rate of nasal carriage among HCWs and patients was lower than global reports. However, the frequency of MRSA was comparable with previously reported ranges and was approximately high. Vancomycin and linezolid are the most effective antimicrobial agents. Appropriate decolonization is recommended for the control of transmission of MRSA to vulnerable individuals.

 Cholestasis is a pathophysiological condition, significantly reducing spermatozoa production. MiR-34c is highly expressed in adult male testicles and controls different stages of spermatogenesis.

 Here, we aimed to investigate miR-34c expression in the testes of rat models of cholestasis. The expressions of THY-1, FGF-2, and CASP-3 genes, that are targeted by mirR-34c were also investigated.

 Cholestasis was induced in six adult rats via bile duct ligation. Four weeks after cholestasis induction, sera and testicular tissues were collected for further examinations. The levels of liver enzymes were measured using the ELISA. The structure of the testes was evaluated by histological examination. Total RNA was extracted from testes using a special kit and converted to cDNA. The expressions of miR-34c-5p, THY-1, FGF-2, and CASP-3 genes were determined by Real-Time PCR.

 The serum levels of ALP, AST, and ALT were significantly elevated in the rat models of cholestasis (P < 0.001). Real-Time PCR revealed that the expressions of miR-34c-5p, THY-1, and FGF-2 genes decreased while CASP-3 gene was upregulated in the testes of cholestatic animals (all differences were significant at P < 0.05).

Our study indicated that cholestasis was associated with reduced expression of miR-34c and altered expression of its target genes in the testis. Our results highlight the potential effects of cholestasis, a hepatobiliary disease, on testicular tissue function and male fertility.

 The enterococcal surface protein (Esp) is a high-molecular-weight surface protein of biofilm creating agent in Enterococcus faecalis. Oxadiazoles have a wide range of biological activities.

 This research aimed to examine the impact of new oxadiazole derivatives on the expression of Esp, playing an important role in promoting the biofilm formation ability of drug-resistant E. faecalis strains.

 1, 3, 4-oxadiazole derivatives were synthesized through a one-step synthesis. E. faecalis strains were collected and isolated from hospitals in Tehran. The antimicrobial properties of the synthesized materials against the isolated strains were investigated. RNA, DNA, and cDNA were extracted, and the relative expression of Esp in E. faecalis isolates was evaluated by real-time PCR. Docking study was performed by AutoDock vina software, and the resulting docking poses were analyzed using Discovery Studio 4.5 Client software.

 The use of synthesized derivatives changed the Esp expression level in different isolates compared to the control sample. The two compounds containing naphthalene (4f) and methoxyphenyl (4g) caused respectively a 2-fold and a 3-fold decrease in Esp expression compared to the control sample. The compound 4f with the best binding energy among the compounds (-9.2) had the most hydrogen and hydrophobic bonds with the receptor-binding site.

 1, 3, 4-oxadiazole derivatives, especially naphthalene and methoxyphenyl, act as inhibitors of bacterial biofilm formation and can be used in the pharmaceutical and biological industries.

 Induced pluripotent stem cells (iPSCs) have the ability to proliferate indefinitely and differentiate into three germ layers of ectoderm, mesoderm, and endoderm. Definitive induction is the first and the most delicate stage of differentiation of various iPSC-derived organs. It has been found that the Wnt signaling pathway implicates in embryogenesis, organogenesis, and cell communication.

 In the present study, we aimed to investigate the expression pattern of the Wnt5a gene as an indicator of non-canonical Wnt signaling activity during definitive endoderm induction of iPSCs.

 Human iPSCs (RSCB0042) were acquired from Royan stem cell bank of Royan Institute (Tehran, Iran). The iPSCs were cultured on a feeder layer of mitomycin-inactivated mouse embryonic fibroblasts (MEF), and iPSC colonies were collected for embryoid body (EB) generation by suspension culture method. Then endoderm induction step was performed using a series of small molecules. The quantitative real-time PCR was used to assess the mRNA expression of wnt5a, Nanog, OCT4, SOX17, and FOXA2 genes.

 The production of efficient EBs confirmed by a decrease in Nanog and Oct4 gene expression and the success of DE (definite endoderm) induction step was confirmed by a high expression level of DE specific genes, Sox17, and FoxA2. A significant upregulation of Wnt5a in EB samples and a minor decrease at day 4 was observed. However, the differentiation process followed by an incremental fashion in Wnt5a mRNA expression starting from day 4 of differentiation among the samples of days 6 and 8 (DE stage).

 Our results suggest that Wnt5a is more activated at the later steps of endoderm induction rather than the early steps, which may be due to the stimulation of canonical Wnt signaling. Finding the expression level of Wnt5a could rise insights for developing more efficient differentiation induction protocols.

 Escherichia coli (Gram-negative bacilli) inflicts large economic losses on the poultry industry and is one of the most important causes of poultry diseases. The indiscriminate use of antibiotics has contributed to today’s increasing prevalence of drug-resistant strains, which their emergence appears to exceed the discovery of new drugs. Therefore, several attempts have been dedicated to find new compounds as effective alternatives to antibiotics. Medicinal plants constitute a rich source for various antimicrobial compounds.

 The aim of this study was to evaluate the antibiotic resistance trend of the E. coli strains isolated from Quail feces samples and to investigate the antimicrobial effects of Eshvarak extract against these strains.

 Eshvarak plant was collected from Saravan (Sistan and Baluchestan province, Iran) and identified in the botany laboratory of Zabol University. E. coli samples were isolated from poultry feces. Various solvents (methanol (100%), ethanol (100%), water (100%), hydro-alcohol (70%), and ethyl-acetate (100%)) were used to prepare Eshvarak extract. Inhibitory zone diameter was determined in an agar-based medium using a standard procedure. The MIC and MBC of prepared extracts were determined by the micro-dilution method.

 The lowest MIC values were obtained for the methanolic (12.5 ppm), ethanolic (12.5 ppm), aqueous (12.5 ppm), hydroalcoholic (25 ppm), and ethyl-acetate (12.5 ppm) Eshvarak extracts. The highest inhibitory zone diameters against E. coli were recorded at the 100-ppm concentration of the methanolic (8 mm), ethanolic (7 mm), aqueous (8 mm), hydroalcoholic (10 mm), and ethyl-acetate (5 mm) Eshvarak extracts.

 Eshvarak extract, particularly in the hydroalcoholic solvent, inhibited the growth of E. coli. However, the antimicrobial properties of plant extracts seem to be independent of the extraction method or the type of solvent.

 Surfactin is a cyclic heptapeptide that is closed by a β-hydroxy fatty acid chain. This potent biosurfactant is produced by different Bacillus subtilis strains. This lipopeptide has numerous attractive biological activities, including antibacterial, antiviral, antimycoplasma, hemolytic, and other different and powerful surface and interface activities.

 Understanding how surfactin binds to different membranes and its mechanism of action can help us modify and optimize its structure to improve the potential efficacy of this lipopeptide in the future. For this purpose, we studied the interaction of this lipopeptide with two types of lipid bilayer models, including palmitoyl-oleoyl-glycero- phosphocholine (POPC) and palmitoyl-oleoyl-phosphtidylglycerol (POPG) as the prokaryotic and eukaryotic membrane models, respectively.

 The obtained data have shown that the tendency of surfactin for these membranes is different. According to the analysis, this molecule binds to both membranes peripherally, and its interaction with the negative membrane is also more potent compared to the zwitterionic membrane. Moreover, we found that surfactin destabilized POPG more than POPC. This suggests that surfactin may act by modifying the membrane’s bulk physical properties.

 As a final point, this study has shown that surfactin has different behaviors in the eukaryotic and prokaryotic cell membranes and can modify and amplify its action in order to use it for antibacterial drugs.

 Arsenic as a widely inadvertently-used metal can trigger oxidative stress, leading to heart diseases.

 In this regard, this study aimed to evaluate the simultaneous effect of regular aerobic exercise and pumpkin seed extract on the heart and aorta endothelial cells' apoptosis in rats poisoned with arsenic.

 To this end, 56 male Wistar rats were divided into seven groups: (1) TC (toxic control), (2) AE (aerobic exercise training), (3) TAP1 (toxic aerobic exercise training + 300 mg/kg/day pumpkin seed extract consumption), (4) TAP2 (toxic aerobic exercise training + 600 mg/kg/day pumpkin seed extract consumption), (5) TP1 (300 mg/kg/day toxic pumpkin seed extract consumption), (6) TP2 (600 mg/kg/day toxic pumpkin seed extract consumption), and (7) HC (healthy control). All the groups (with the exception of HC) were exposed to 25 ppm arsenic per day for 16 weeks. Then aerobic exercise training program or pumpkin seed extract, or both, were administered to rats depending on the groups for eight weeks. Twenty-four hours after the last intervention session, the rats were killed, and their tissues were collected. Statistical analyses were performed, and P ≥ 0.05 was set as the significance level.

 The results showed that pumpkin seed extract lowered BCL2-associated X protein (Bax) and caspase-3 levels and increased B-cell lymphoma 2 (Bcl2) significantly only at a dose of 600 mg/kg; however, no change was observed when only aerobic exercise training was performed. The groups who received both interventions had more significant changes in the heart and aorta tissues for all factors.

 It was concluded that the concurrent administration of aerobic exercise training and pumpkin seed extract could decrease apoptosis more significantly in both tissues in arsenic-intoxicated rats, compared to each individual intervention