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Reza Ranjbar, Abbas Farahani Molecular Biology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, IranCorrespondence: Reza RanjbarMolecular Biology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, IranTel +98 21 8803 9883Email Ranjbarre@gmail.comAbstract: Shigella spp. are a common cause of diarrheal disease and have remained an important pathogen responsible for increased rates of morbidity and mortality caused by dysentery each year around the globe. Antibiotic treatment of Shigella infections plays an essential role in reducing prevalence and death rates of the disease. However, treatment of these infections remains a challenge, due to the global rise in broad-spectrum resistance to many antibiotics. Drug resistance in Shigella spp. can result from many mechanisms, such as decrease in cellular permeability, extrusion of drugs by active efflux pumps, and overexpression of drug-modifying and -inactivating enzymes or target modification by mutation. Therefore, there is an increasing need for identification and evolution of alternative therapeutic strategies presenting innovative avenues against Shigella infections, as well as paying further attention to this infection. The current review focuses on various antibiotic-resistance mechanisms of Shigella spp. with a particular emphasis on epidemiology and new mechanisms of resistance and their acquisition, and also discusses the status of novel strategies for treatment of Shigella infection and vaccine candidates currently under evaluation in preclinical or clinical phases.Keywords: Shigella, antibiotics, resistance, drug resistance, mechanism, treatment, biofilm, efflux pumps, prevention, vaccine

Ahmad Farajzadah Sheikh,1,2 Hamed Goodarzi,1–3 Mohammad Jaafar Yadyad,1 Sajad Aslani,4 Mansoor Amin,1,2 Nabi Jomehzadeh,5 Reza Ranjbar,3 Mina Moradzadeh,1 Samireh Azarpira,1 Mohamad Reza Akhond,6 Mohamad Hashemzadeh1,21Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; 2Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; 3Molecular Biology Research Center, Baqiyatallah University of Medical Science, Tehran, Iran; 4Student Research Committee, Kerman University of Medical Sciences, Kerman, Iran; 5Abadan Faculty of Medical Sciences, Abadan, Iran; 6Department of Statistics, Mathematical Science and Computer Faculty, Shahid Chamran University, Ahvaz, IranBackground: Different Escherichia coli phylogenetic groups, such as A, B1, B2, and D, have four functional groups – adhesins, microcins, toxins, and capsules – which can cause urinary tract infections (UTIs). A phylogenetic group with a high virulence content becomes a worldwide health concern. Resistance to antimicrobial agents increasingly complicates the management of E. coli extraintestinal infections, as a major source of illness, death, and increased health care costs. The aim of this study was to determine the virulence content and the antimicrobial susceptibility pattern of different uropathogenic E. coli (UPEC) phylogenetic groups in Ahvaz, Iran.Methods: Phylogenetic groups, virulence-associated genes (VAGs), and antimicrobial susceptibility tests were detected by molecular and phenotypic methods in a total of 232 clinically well-characterized E. coli strains, isolated from two collections of patients with hospital-acquired (HA) and community-acquired (CA) UTIs.Results: Our results revealed that among 232 UPEC strains, the most frequent phylogenetic group was phylogroup D (58%) with the greatest content in virulence factors, including kpsM (23%), neuA (76.3%, capsule), cnf (29.6%, toxin), and Pap (54.8%, adhesin). Phylogroups D and, to a lesser extent, B2 were the most drug-resistant phylogroups. In addition, phylogroup D was responsible for the majority of HA (64.7%) and CA (48.4%) infections.Conclusion: Among UPEC strains causing UTIs, different phylogroups, through different VAGs, could cause severe infection. Knowledge about the distribution of the four functional groups and VAGs belonging to these phylogroups would significantly help to confine and prevent the development of lethal infection caused by these strains.Keywords: uropathogenic Escherichia coli, drug resistance, virulence factors, Iran

Reza Ranjbar,1 Ali Fatahian Kelishadrokhi,2 Mohammad Chehelgerdi21Molecular Biology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran; 2Biotechnology Research Center, Shahr-e Kord Branch, Islamic Azad University, Shahr-e Kord, IranPurpose: Virulent and resistant Klebsiella pneumoniae strains are considered as one of the most significant causes of hospital-acquired infections. The present investigation was done to study the distribution of virulence factors, capsule serotypes and phenotypic and genotypic evaluation of antibiotic resistance of the K. pneumoniae strains isolated from hospital-acquired infections.Patients Materials and methods: Two hundred and sixty different types of hospital-acquired infections were collected and cultured. Antibiotic resistance pattern of K. pneumoniae isolates and their molecular characterization were studied using disk diffusion and PCR, respectively.Results: One hundred and fifty out of 260 (44.22%) hospital-acquired infections harbored K. pneumoniae. Urine samples (63.75%) had the highest prevalence of K. pneumoniae, while wound (33.33%) had the lowest. K. pneumoniae strains harbored the highest prevalence of resistance against ampicillin (100%), cefuroxime (100%), amoxicillin/clavulanic acid (95.65%) and ceftazidime (95.52%). FimH-1 (93.04%), traT (92.17%), mrkD (84.34%), and entB (80.86%) were the most commonly detected virulence genes. AcrAB (96.52%) and tolC (85.21%) were the most commonly detected antibiotic resistance genes. Prevalence of ompK35 and ompK36 virulence genes were 75.65% and 79.13%, respectively. Prevalence of K1 and K2-positive serotypes were 27.82% and 6.96%, respectively.Conclusions: High prevalence of resistance against several types of antibiotics and simultaneous presence of some virulence factors and multi-drug resistance genes pose an important public health issue.Keywords: Klebsiella pneumoniae, antibiotic resistance pattern, antibiotic resistance genes, capsule serotypes, virulence genes, hospital infections

Reza Ranjbar,1 Mohammad Chehelgerdi2 1Molecular Biology Research Center, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran; 2Biotechnology Research Center, Shahr-e Kord Branch, Islamic Azad University, Shahr-e Kord, Iran Purpose: The present study was done to assess the prevalence rate, antibiotic resistance pattern and genotyping status of the Helicobacter pylori strains isolated from human and animal gastric biopsy samples.Patients and methods: A total of 1,150 gastric biopsy samples were randomly collected from humans (children and adults) and animals (cows, sheep and goats). All samples were subjected to culture, urease test and histopathologic examination. H. pylori isolates were also confirmed using the 16S rRNA gene PCR-amplification. Antibiotic resistance pattern was assessed by the disk diffusion method. Distribution of different genotypes was studied by PCR.Results: The prevalence of H. pylori in gastric biopsy samples which were studied using urease test, culture and histological examination were 57.04%, 55.40% and 60.80%, respectively. Samples that were collected from adult humans (78%) and sheep (70%) had the highest prevalence of H. pylori strains, while those of goats (0.6%) and cows (4%) had the lowest. Findings of the culture method were confirmed using PCR-based amplification of 16S rRNA. Distribution of H. pylori among the gastric ulcers, duodenal ulcers, chronic gastritis gastric cancer and chronic cancer samples were 10.40%, 15.70%, 96.50%, 0.60% and 3.14%, respectively. H. pylori strains harbored the highest prevalence of resistance against ampicillin (74.4%), clarithromycin (63.4%), trimethoprim (61.5%) and metronidazole (61.5%). The most commonly detected genotypes among the H. pylori strains isolated from different types of biopsy samples were cagA (84.79%), vacA m2 (55.95%), vacA s1a (49.84%), cagE (48.58%), iceA1 (47.02%) and iceA2 (47.02%).Conclusion: High prevalence of antibiotic resistance and virulent genotypes indicates an important public health issue. Similarities in antibiotic resistance and genotyping pattern of H. pylori strains isolated from humans and animals may show their similar routes of infection. Keywords: Helicobacter pylori, virulence factor, antibiotic resistance, genotypes, clinical samples

Enterococcus faecalis (E. faecalis) and E. faecium (E. faecium) are commensals of the gastrointestinal biota of humans and animals and are considered opportunistic pathogens. This study aimed to improve the knowledge about E. faecalis and E. faecium isolated from meat. To this end, 104 meat samples were collected from sheep, goats, cattle, and calves from Shahrekord local markets in Iran. Presumptive colonies of E. faecalis and E. faecium were isolated from the samples and subjected to identification tests. Antimicrobial susceptibility was determined using the Kirby-Bauer disc diffusion method, and polymerase chain reaction (PCR) was performed to detect some virulence genes. Furthermore, randomly amplified polymorphic DNA typing and repetitive element sequencebased PCR fingerprinting were used to show the clonal relatedness of the isolates. The results revealed that enterococci were present in 90 out of 104 samples. Specifically, E. faecalis and E. faecium were the commonly isolated species, with the predominance of E. faecalis, which exhibited high resistance to streptomycin (95%) but was susceptible to vancomycin (85.6%). Virulence genes detection showed that ccf and cpd genes were the most prevalent genes in both species. In addition, the molecular typing method indicated that the isolates belonged to separate subgroups. This study shows the contamination of meat products by potential pathogens and resistant enterococci. There is a need to implement regular surveillance to monitor the emergence of antimicrobial-resistant E. faecalis and E. faecium in food, particularly in meat production. [ABSTRACT FROM AUTHOR]

Background. Phobia as a psychological disorder seems to be aggravated during health crises like the current COVID-19 outbreak. On the other hand, people's knowledge about a situation can help decrease the resulting fear. Study design. This is a cross-sectional analytical study to evaluate the COVID-19 related phobia and to measure knowledge, attitude, and practice of our target Iranian population about COVID-19. Methods. In this study, DSM-5 specific phobia questionnaire, adapted to SARS-CoV2-19 infection, was used to evaluate the COVID-19 related phobia. Moreover, the knowledge, attitude, and practice (KAP) questionnaire, specific for SARS-CoV-2 infection, was applied. Results. Phobia score was significantly higher in 1st-degree relatives of healthcare staff (20.38±5.82) than healthcare staff (18.36±5.68) (p=0.021). Females showed a significantly more severe phobia (20.27±5.41) than males (17.72±5.35, p=0.001). COVID-19 phobia was significantly more severe in those with past psychiatric conditions than in those without psychiatric history (p<0.05). The 1st-degree relatives of healthcare staff had a significantly lower level of knowledge about SARS-CoV-2 infection (8.19±1.65) than healthcare staff (9.08±1.28, p=0.001). Additionally, age had a positive significant correlation with knowledge and practice towards SARS-CoV-2 infection. Conclusion. Both Iranian healthcare staff and 1st-degree relatives of healthcare workers are suffering from moderate COVID-19 phobia. Females are more concerned than males about COVID-19. Phobia is more severe in people with underlying psychiatric conditions than other people. The knowledge level of Iranian healthcare workers and 1st-degree relatives of healthcare staff about COVID-19 is acceptable but it needs improvement in certain areas. [ABSTRACT FROM AUTHOR]

Mn-based hard magnets are potentially suitable for advanced ultra-high frequency spintronics applications because they exhibit the Larmor precession of magnetization at THz wave-range frequencies with low magnetic relaxation. However, the low magnetic relaxation properties are not well understood; thus, a more detailed study is necessary. In this study, magnetization precessions in L10 Mn1.54Ga, D022 Mn2.12Ga, and C38 MnAlGe epitaxial films grown on MgO substrates were investigated using an all-optical pump-probe method under a magnetic field of ~20 kOe. The coherent magnetization precessions at frequencies of more than 0.1, 0.2, and 0.3 THz for the C38 MnAlGe, L10 Mn1.54Ga, and D022 Mn2.12Ga films, respectively, were clearly measured. The effective damping constant for the C38 MnAlGe film was smaller than the previously reported value measured at 10 kOe by a factor of 2, whereas those showed a large angular dependence. The effective damping constants for the L10 Mn1.54Ga and D022 Mn2.12Ga films were independent of the field angle and approximately identical to the values measured at 10 kOe. Thus, it was concluded that the values for the Gilbert damping constant, α, were 0.008 and 0.012 for the L10 Mn1.54Ga and D022 Mn2.12Ga films, respectively. The possible origin of the discrepancy between the experimental and theoretical a values for these films is discussed. [ABSTRACT FROM AUTHOR]

We have fabricated bilayer films of tetragonal Heusler-like D022 Mn3Ga and cubic Heusler Co2FeZ (Z=Si and Al) on (100) single-crystalline MgO substrates and investigated their structural and interfacial exchange coupling. The coupling in the Mn3Ga/Co2FeAl bilayer was either ferromagnetic or antiferromagnetic, depending on annealing temperature, whereas only antiferromagnetic exchange coupling was observed in the Mn3Ga/Co2FeSi bilayers. The effects of annealing on the structure and coupling strength in the bilayers are discussed. [ABSTRACT FROM AUTHOR]

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This study investigates the spectral shifting UV-A radiation by fluorescent material as a tool for enhancing Chlorella sp. growth rate in photobioreactors made of UV-stabilized polycarbonate (PC). The fluorescent dye was dissolved in a thermoplastic acrylic resin, and the mixture was applied as a coating on to the substrates. The feasibility of using the fluorescent coating as wavelength shifter layer to shift UV-A radiation of a full spectrum light source to the photosynthetically active region (PAR) was explored. For this purpose, a solution of the fluorescent dye in resin was prepared and used to coat front surface of the reactor. Comparing to the uncoated reactor, the reactor coated with the wavelength shifter layer exhibited about 10 % increase in biomass productivity over the same culture period. It was also found that the elimination of UV-A radiation increases chlorophyll a content in the cells. [ABSTRACT FROM AUTHOR]

A recently introduced metric for assessing metabolic syndrome (MetS) is the triglyceride glucose-body mass index (TyG-BMI). Additionally, the glycemic index (GI) is recognized as a significant measure for evaluating conditions associated with blood glucose. In this context, our research explores the correlation between TyG-BMI and GI in relation to diet quality, anthropometric measurements, and blood pressure among individuals diagnosed with MetS. A cross-sectional descriptive-analytical study was conducted on 431 employees with MetS at Shiraz University of Medical Sciences (SUMS). Anthropometric measurements of height, weight, waist circumference (WC), and hip circumference (HC) were taken according to Persian cohort protocols. BMI, C-index, visceral adiposity index (VAI), body adiposity index (BAI), body shape index (ABSI), abdominal volume index (AVI), potential renal acid load (PRAL), TyG-BMI and GI were calculated. A physician measured blood pressure, while the dietary inflammatory index was determined using guidelines. Biochemical parameters were analyzed using standard laboratory techniques. Data analysis was conducted using SPSS software version 21, with a significance threshold set at <.05. A significant correlation was identified between the TyG-BMI index and the PRAL index (β = 0.094, P-value = .026), WC (β = 0.627, P-value < .001), BAI (β = 0.396, P-value < .001), and blood pressure (β = 0.063, P-value = .002). Furthermore, the findings indicated a notable association between the GI and blood pressure (β = 0.610, P-value < .001). The results of this study suggest that managing the PRAL index, body weight, and blood pressure may be associated with an enhanced status of TyG-BMI. Additionally, appropriate GI may be linked to regulated blood pressure. These findings can inform health-related policy decisions for these patients., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2025 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background: Eccentric exercise (ECC) can induce NLRP3-related inflammation in skeletal muscle tissue. Limited available data have shown that Cold water immersion (CWI) after ECC can suppress skeletal muscle inflammation. This study aims to investigate the effect of CWI after ECC on the NLRP3 inflammasome pathway, and the expression of ubiquitin-proteasome-related proteins (UPPs) in the skeletal muscle of rats., Methods: Twenty-five male Wistar rats were randomly divided into control, ECC, ECC + CWI, ECC + NWI (normal water immersion), and ECC + AR (active recovery) groups. The Eccentric exercise consisted of 90 min of downhill running on a treadmill with a speed of 16 m/min and -16° incline. Animals in the NWI and CWI groups were immersed in water at 25 °C and 10 °C after ECC. Eventually, The soleus muscle was isolated and the expression of NLRP3, caspase-1, FBXL2, TRIM31, and PARKIN was evaluated by western blot. Tissue levels of IL-1β and IL-18 were measured by ELISA assay., Results: ECC significantly increased the expression of NLRP3, caspase-1, and the tissue levels of IL-1β and IL-18 compared to the control group. After ECC, FBXL2, and PARKIN were downregulated, whereas TRIM31 was up-regulated (P < 0.05). CWI after ECC suppressed the NLRP3 inflammasome components and increased the protein levels of FBXL2 and TRIM31 at higher levels than other recovery methods (P < 0.05). CWI and AR had the same increase in PARKIN expression and the same decrease in CK level compared to the ECC group (P < 0.05)., Conclusion: Our results indicated that CWI increased the expression of NLRP3-related UPPs in concomitant with suppression of NLRP3 in the soleus muscle of rats after ECC. As a result the beneficial effects of CWI on the attenuation of skeletal muscle inflammation may contribute to an alteration of UPPs expression., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Formaldehyde (FA) as a common organic compound has been shown to cause placental dysfunction and fetal defects. The potential benefits of fish oil (FOil) in protecting placental structures are attributed to its antioxidant properties. This study aimed to explore the preventive role of FOil in mitigating the adverse effects of FA in pregnant rats. Thirty pregnant Wistar rats were randomly categorized into five groups of control, sham (Normal saline; Orally and intraperitoneally), FOil (0.5 ml/day; Orally), FA (5 mg/kg/bw; intraperitoneally), FA+FOil. The treatment period was from day 0-20 of pregnancy. On the 20th day of pregnancy, placental morphometric parameters were measured. The histological and histochemical analyses were performed using H&E and PAS staining, respectively. Also, the placenta tissue was analyzed for oxidative stress biomarkers, p-53 protein levels, and the expression of caspase-3 gene. The administration of FA led to a significant decrease in the weight, diameter, and thickness of the placenta, as well as a decrease in the thickness of the decidua layer, junctional and labyrinth zone, and the number of trophoblast giant cells in rat placentas. FA led to a significant increase in placental p-53 protein levels, caspase-3 expression, and oxidative stress biomarkers. Administration of FOil to pregnant rats treated with FA led to a significant decrease in morphometric and histological changes, oxidative stress, and the expression of genes associated with apoptosis. The findings suggest that the administration of FOil to FA-treated pregnant rats can protect placental histopathological changes by enhancing the activity of the antioxidant enzymes., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

One of the most common bacteria that cause nosocomial infections is Klebsiella pneumonia (K. pneumoniae), especially in patients who are very sick and admitted to the intensive care unit (ICU). The frequency of multi-drug-resistant Klebsiella pneumoniae (MDRKP) has dramatically increased worldwide in recent decades, posing an urgent threat to public health. The Western world's bacteriophage (phage) studies have been revitalized due to the increasing reports of antimicrobial resistance and the restricted development and discovery of new antibiotics. These factors have also spurred innovation in other scientific domains. The primary agent in phage treatment is an obligately lytic organism (called bacteriophage) that kills the corresponding bacterial host while sparing human cells and lessening the broader effects of antibiotic usage on commensal bacteria. Phage treatment is developing quickly, leading to many clinical studies and instances of life-saving medicinal use. In addition, phage treatment has a few immunological adverse effects and consequences in addition to its usefulness. Since K. pneumoniae antibiotic resistance has made treating multidrug-resistant (MDR) infections challenging, phage therapy (PT) has emerged as a novel therapeutic strategy. The effectiveness of phages has also been investigated in K. pneumoniae biofilms and animal infection models. Compared with antibiotics, PT exhibits numerous advantages, including a particular lysis spectrum, co-evolution with bacteria to avoid the emergence of phage resistance, and a higher abundance and diversity of phage resources than found in antibiotics. Moreover, phages are eliminated in the absence of a host bacterium, which makes them the only therapeutic agent that self-regulates at the sites of infection. Therefore, it is essential to pay attention to the role of PT in treating these infections. This study summarizes the state of knowledge on Klebsiella spp. phages and provides an outlook on the development of phage-based treatments that target K. pneumoniae in clinical trials., (© 2024. The Author(s).)