Antimicrobial resistance patterns, virulence genes, and biofilm formation in enterococci strains collected from different sources.

BACKGROUND: Currently, antibiotic-resistant strains of Enterococcus are considered to be one of the critical health challenges globally. This study aimed to investigate the antibiotic susceptibility pattern, biofilm formation capacity, and virulence genes of enterococci isolated from different sources. METHODS: In this cross-sectional study, environmental and fecal samples were collected from the hospital environment, volunteers, and hospital staff from October 2018 to August 2019. The isolates were identified by morphological and biochemical tests (gram staining, catalase, bile resistance, esculin hydrolysis, carbohydrate fermentation, growth in 6.5% NaCl, Pyrrolidonyl arylamidase, arginine dehydrolase), and PCR for ddl gene. An antimicrobial susceptibility test was performed by the standard disk agar diffusion method according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. Quantitative microplate assays were used to assess biofilm production. The bacterial DNAs were extracted by alkaline lysis method and polymerase chain reaction technique was used detect the esp, ace, and efaA virulence genes. RESULTS: Out of 145 isolates, 84 (57.9%) were identified as E. faecalis and 61 (42.1%) as E. faecium. Resistance to kanamycin and quinupristin-dalfopristin was 82.1% (69/84) and 85.7% (72/84), respectively, in E. faecalis isolates. Out of 61 E. faecalis isolates, 38 (62.4%) were resistant to kanamycin. Among the E. faecalis isolates, esp was the most dominant virulence gene (73.80%), followed by efaA, and ace, which were detected in 60.71%, and 30.95% isolates, respectively. In total, 68.27% of the strains were biofilm producers. Further, esp and efaA genes were more frequently found among E. faecalis strains with moderate and strong biofilm biomass. CONCLUSIONS: According to the findings of our study, enterococci strains isolated from different samples possess distinctive patterns of virulence genes. The esp, ace, and efaA genes were more prevalent among E. faecalis than E. faecium. Besides, the high level antibiotic resistance of normal flora and environmental enterococci strains is alarming the researchers.

Alpha-lipoic acid enhances ischemic postconditioning-mediated improvement of myocardial infarction and apoptosis in diabetic rats with ischemia/reperfusion injury.

This work evaluated the combined effects of alpha-lipoic acid (ALA) and ischemic postconditioning (Post) on myocardial infarction and cell death in rats with chronic type-II diabetes following ischemia/reperfusion injury. The rats received a high-fat diet and were given one intraperitoneal injection of 35 mg/kg streptozotocin to induce chronic diabetes. They were then pretreated with ALA (100 mg/kg/day, orally) for 5 weeks before undergoing ischemia/reperfusion (I/R) insult. The hearts experienced 35 min regional ischemia through ligating the left anterior descending coronary artery, followed by 60 min reperfusion. The Post protocol involved 6 cycles of a 10/10 s algorithm, applied during the early stage of reperfusion. The use of Post alone did not significantly alter lactate dehydrogenase and infarct size levels, while ALA showed positive effects. Similar findings were observed for apoptotic changes with single treatments. However, the concurrent administration of ALA and Post significantly reduced the protein expressions of Bax, Bax/Bcl2, and cleaved caspase-3 while increasing Bcl2 expression. Additionally, the histopathological findings of the combined therapy were superior to those of single treatments. The concomitant use of ALA and Post effectively inhibited apoptosis, leading to cardiac recovery after I/R injury in diabetic conditions. This strategy could improve outcomes for preserving diabetic hearts following I/R insults.

Alpha-lipoic acid potentiates the anti-arrhythmic effects of ischemic postconditioning in the setting of cardiac ischemia/reperfusion injury in diabetic rats.

Background: Prevention of lethal ventricular arrhythmias induced by myocardial ischemia/reperfusion (I/R) in diabetic patients is the major goal of cardioprotective strategies. Here, we aimed to examine the anti-arrhythmic effect of ischemic postconditioning (IPostC) and alpha-lipoic acid (ALA) in myocardial I/R injury of type-II diabetic rats, focusing on the involvement of connexin-43 and nitric oxide (NO) in this context. Methods: Diabetes (duration of 12 weeks) was induced by high-fat diet and low dose of streptozotocin in thirty male Wistar rats (12 weeks old, 200-250 g). After mounting the hearts on the Langendorff apparatus, I/R was induced by the ligation of left anterior descending coronary artery for 35 min, and reperfusion for 60 min. ALA (100 mg/kg/day) was administered orally in diabetic rats for five weeks before I/R. IPostC was applied immediately at early reperfusion. The arrhythmias were evaluated according to the Lambeth convention. Connexin-43 expression and NO levels were assessed by western blotting and Griess calorimetric method, respectively. Results: IPostC could not significantly decrease the number, duration, and incidence of premature ventricular contraction, ventricular tachycardia, and ventricular fibrillation, also the severity of arrhythmias in diabetic hearts. However, IPostC in combination with ALA-preconditioning significantly decreased the above mentioned parameters compared with untreated or monotherapies-received diabetic rats (P < 0.05 to P < 0.001). Furthermore, this combination therapy significantly increased connexin-43 expression and NO levels, compared with untreated diabetic rats (P < 0.01). Conclusion: Preconditioning with ALA restored anti-arrhythmic effect of IPostC in diabetic hearts. Increased connexin-43 expression and NO levels may be the key players in this cardioprotection.

Evaluation of polysaccharide intercellular adhesion (PIA) and glycerol teichoic acid (Gly-TA) arisen antibodies to prevention of biofilm formation in Staphylococcus aureus and Staphylococcus epidermidis strains.

OBJECTIVE: Staphylococcus aureus and S. epidermidis as opportunistic pathogens, notable for their frequency and severity of infections are recognized as the most usual reasons for medical device-associated infections that strike hospitalized patients and also immunocompromised individuals. In this study, the polysaccharide intercellular adhesion (PIA) and Glycerol teichoic acid) Gly-TA) as two major macromolecules in the biofilm formation process were purified under the native condition and their structure was analyzed by using colorimetric assays and Fourier Transform Infrared spectroscopy (FTIR). Afterward, the immune response of macromolecules and the mixture of them were assessed by measuring total IgG titers. Subsequently, biofilm inhibitory effects of raising antibodies to biofilm former S. aureus and S. epidermidis were evaluated. RESULTS: Obtained data were shown a significant rise in levels of antibodies in immunized mice with mentioned antibodies in comparison with the control group. According to the obtained findings, mentioned antibodies could eliminate S. aureus and S. epidermidis biofilm formation in vitro assays. This survey confirms the proposal that immunization of mice with a mixture of Gly-TA and PIA vaccine could be secure and protected against S. epidermidis and S. aureus infection.

Construction and analysis of alginate-based honey hydrogel as an ointment to heal of rat burn wound related infections.

Developing a strategy for making the alginate base hydrogel components against burned wound infections could be promising for healing the mentioned wounds followed by elimination of the biofilm forming bacteria colonization. Construction of an alginate based hydrogel and evaluating healing activities of the mentioned component as local ointment were the main objectives of the current study. Following the collection of the honey from three different provinces of Iran, the components and structures of the collected materials were analyzed taking advantage of INSO-92 procedure subsequently, antibacterial effect of diluted three different kinds of honey against wild-type bacterial species got evaluated via agar well diffusion method. An alginate base hydrogel was prepared by the use of calcium chloride as a linker between the alginate and honey functional groups. Then, component was structurally analyzed by Fourier Transform Infrared spectroscopy (FTIR). Afterward, under in vivo conditions, the healing activities of prepared ointment were studied in infected burned rat models. According to the antibacterial effect of the honeys, 75% diluted thymol based honeys collected from Damavand province were the most efficient ones. Furthermore, it was the healing activity of mentioned ointment was proven in vivo studies. The difference between 1600-1800 wave numbers in constructed alginate-based hydrogel alginate and honey because of C = O bond variations structurally confirmed proper construction of hydrogel. The hydrogel was the better healing activity in rats burned wound too. In conclusion the promising efficiency of alginate-based hydrogel in an elimination of bacterial infections was confirmed as the main aim of the current survey.

Terminal Deoxynucleotidyl Transferase (TdT) Inhibiti on of Cord Blood Derived B and T Cells Expansion.

Purpose: Terminal deoxynucleotidyl transferase(TdT) is a DNA polymerase that is present in immature pre-B and pre-T cells. TdT inserts N-nucleotides to the V (D) J gene segment during rearrangements of genes, therefore, it plays a vital role in the development and variation of the immune system in vertebrates. Here we evaluated the relationship between cytokines like interleukin-2 (IL-2), interleukin-7 (IL-7), and interleukin-15 (IL-15) and TdT expression in cord blood mononuclear cells and also effect of inhibition in the expansion of B and T cells derived from cord blood. Methodes: The cord blood mononuclear cells were cultured with different combination of cytokines for 21days, which they were harvested in definite days (7, 14 and 21) and evaluated by flow cytometry. Results: Our data indicated that TdT expression increased in cord blood mononuclear cells using immune cell key cytokines without being dependent on the type of cytokines. TdT inhibition reduced both the expansion of B and T cells derived from cord blood and also declined the apoptosis and proliferation. Considered together, TdT played an important role in the control of the expansion of B and T cells derived from cord blood. Conclusion: considered together, it was observed that TdT expression was increased by cytokines and TdT inhibition not only reduced B and Tcells derived from cord blood, but it also affected the rate of apoptosis and proliferation.

Impact of C-rel inhibition of cord blood-derived B-, T-, and NK cells.

The c-Rel transcription factor is a unique member of the nuclear factor (NF)-κB family that has a role in curtailing the proliferation, differentiation, cytokine production, and overall activity of B- and T-cells. In addition, c-Rel is a key regulator of apoptosis in that it influences the expression of anti-apoptotic genes such as Bcl-2 and Bcl-xL; conversely, inhibition of c-Rel increases cell apoptosis. To better understand the relationship between c-Rel expression and effects on B- and T-cell expansion, the current study evaluated c-Rel expression in cord blood mononuclear cells. This particular source was selected as cord blood is an important source of cells used for transplantation and immunotherapy, primarily in treating leukemias. As stem cell factor (SCF) and FLT3 are important agents for hematopoietic stem cell expansion, and cytokines like interleukin (IL)-2, -7, and -15 are essential for T- and B- (and also NK) cell development and proliferation, the current study evaluated c-Rel expression in cord blood mononuclear cells and CD34+ cells, as well as effects on B-, T-, and NK cells associated with alterations in c-Rel expression, using flow cytometry and PCR. The results showed c-Rel expression increased among cells cultured in the presence of SCF and FLT3 but was reduced when IL-2, IL-7, and IL-15 were used all together. Further, inhibition of c-Rel expression by siRNA reduced cord blood-derived B-, T-, and NK cell differentiation and expansion. These results indicated that with cells isolated from cord blood, c-Rel has an important role in B-, T-, and NK cell differentiation and, further, that agents (select cytokines/growth factors) that could impact on its expression might not only affect immune cell profiles in a host but could potentially also limit apoptotic activities in (non-)immune cells in that host. In the context of cancer (immuno)therapy, in particular, when cord blood is used an important source in stem cell transplantation in leukemia patients, such down-regulating changes in c-Rel levels could be counter-productive.

Connective tissue graft vs. emdogain: A new approach to compare the outcomes.

BACKGROUND: The aim of this clinical trial study was to clinically evaluate the use of enamel matrix protein derivative combined with the coronally positioned flap to treat gingival recession compared to the subepithelial connective tissue graft by a new method to obtain denuded root surface area. MATERIALS AND METHODS: Thirteen patients, each with two or more similar bilateral Miller class I or II gingival recession (40 recessions) were randomly assigned to the test (enamel matrix protein derivative + coronally positioned flap) or control group (subepithelial connective tissue graft). Recession depth, width, probing depth, keratinized gingival, and plaque index were recorded at baseline and at one, three, and six months after treatment. A stent was used to measure the denuded root surface area at each examination session. Results were analyzed using Kolmogorov-Smirnov, Wilcoxon, Friedman, paired-sample t test. RESULTS: The average percentages of root coverage for control and test groups were 63.3% and 55%, respectively. Both groups showed significant keratinized gingival increase (P < 0.05). Recession depth decreased significantly in both groups. Root surface area was improved significantly from baseline with no significant difference between the two study groups (P > 0.05). The results of Friedman test were significant for clinical indices (P < 0.05), except for probing depth in control group (P = 0.166). CONCLUSION: Enamel matrix protein derivative showed the same results as subepithelial connective tissue graft with relatively easy procedure to perform and low patient morbidity.

Antioxidant activity of protein hydrolysates from whole anchovy sprat (Clupeonella engrauliformis) prepared using endogenous enzymes and commercial proteases.

BACKGROUND: The antioxidant activity and chemical properties of fish protein hydrolysates (FPHs) prepared from anchovy sprat (Clupeonella engrauliformis) using endogenous enzymes (autolysis) and commercial proteases were investigated. RESULTS: The highest degree of hydrolysis (DH) was observed with Alcalase and papain and the highest protein recovery (PR) with Alcalase and bromelain. FPH yield was highest with Alcalase (82.3%) and lowest with autolysis (63.64%). Increased DH resulted in increased FPH yield (R(2) = 0.77). The highest oil recovery was observed with bromelain (6.41%) and the lowest with autolysis (3.58%). Antioxidant activity determined by DPPH, reducing power and ferrous chelation assays was highest in bromelain, Promod and papain FPHs respectively. The highest ABTS activity was observed in Alcalase FPH, followed by Promod and Protamex™ FPHs. The lowest antioxidant activity was observed in autolysed and Flavourzyme FPHs (P > 0.05). Heavy metals (arsenic, lead and mercury) were recorded at levels below the regulatory limits established by the FDA. CONCLUSION: Anchovy sprat hydrolysates showed high antioxidant activities and amino acid contents and low heavy metal concentrations, indicating that they have high potential for use in human and animal diets. The high antioxidant activities are related to the high levels of hydrophobic amino acids found in this study.

Design, synthesis and antifungal activity of some new imidazole and triazole derivatives.

Triazole and imidazole are incorporated into the structures of many antifungal compounds. In this study a novel series of 1,2,4-triazole, imidazole, benzoimidazole, and benzotriazole derivatives was designed as inhibitors of cytochrome P450 14α-demethylase (14DM). These structures were docked into the active site of MT-CYP51, using Autodock program. Sixteen compounds with the best binding energy were synthesized. The chemical structures of the new compounds were confirmed by elemental and spectral ((1) H-NMR and Mass) analyses. All compounds were investigated for antifungal activity against Candida albicans, Candida tropicalis, Candida glabrata, Candida parapeilosis, Candida kruzei, Candida dubliniensis, Aspergillus fomigatus, Aspergillus flavus, Microsporum canis, Microsporum gypseum, Trichophyton mentagrophyte, Epidermophyton floccosum. Some compounds showed excellent in-vitro antifungal activity against most of the tested fungi. Compounds 2, 9, and 10 had antifungal activity against several resistant fungi against fluconazole and itraconazole.