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Helicobacter pylori (H. pylori) is one of the most prevalent human pathogens and the leading cause of chronic infection in almost half of the population in the world (~59%). The bacterium is a major leading cause of chronic gastritis, gastric and duodenal ulcers, and two type of malignancies, gastric adenocarcinoma and mucosa‐associated lymphoid tissue (MALT) lymphoma. Despite the immune responses mounted by the host, the bacteria are not cleared from the body resulting in a chronic infection accompanied by a chronic inflammation. Herein, a review of the literature discussing H. pylori antigens modulating the immune responses is presented. The mechanisms that are involved in the modulation of innate immune response, include modulation of recognition by pattern recognition receptors (PRRs) such as modulation of recognition by toll like receptors (TLR)4 and TLR5, modulation of phagocytic function, and modulation of phagocytic killing mediated by reactive oxygen species (ROS) and nitric oxide (NO). On the other hands, H. pylori modulates acquired immune response by the induction of tolerogenic dendritic cells (DCs), modulation of apoptosis, induction of regulatory T cells, modulation of T helper (Th)1 response, and modulation of Th17 response. [ABSTRACT FROM AUTHOR]

The emergence of multidrug-resistant pathogens leads to treatment failure. So, the need for new antibacterial drugs is urgent. We evaluated the antibacterial and antibiofilm effects of titanium dioxide (TiO2) nanoparticles (NPs) and Ganoderma extract against biofilm-producing Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus (MRSA) by microbroth dilution and crystal violet assays. The combined effect of these compounds was studied using the checkerboard method. The OD260 was measured to assess the destruction of the membrane permeability. The expression of biofilm-related genes (iacA and algD) was investigated by real-time PCR. MRSA isolate was more susceptible to test compounds. The OD260 increased and algD gene was down-regulated after treatment with TiO2 NPs and a combination of TiO2 NPs and Ganoderma extract. iacA gene did not affect by test compounds. Overall, these findings revealed that nanoparticles and natural substances might represent the potential candidates to develop promising antibacterial agents, especially against Gram-positive bacteria. [ABSTRACT FROM AUTHOR]

Background: Mycobacterium tuberculosis affects the lungs in 85% of all cases and the remaining 15% through extra pulmonary affecting other parts of the body such as lymph nodes, pleura, and the genitourinary system. This study aimed to investigate extra-pulmonary tuberculosis (TB) associated factors, failure of treatment, and trends between 2004-2017 in Kashan, Iran. Materials and Methods: This study was conducted during 2004-2017 on newly registered extrapulmonary tuberculosis patients referred to TB Referral Center in Isfahan province, Kashan city, Iran. Information (demographic characteristics, related factors of the disease, and treatment status) of 197 extrapulmonary tuberculosis (EPTB) patients was extracted from Medical case records. Results: In total, 527 cases of Tuberculosis were reported, of which, 159 (30.17%) were confirmed extrapulmonary TB. Eighty-five (53.5%) and 74 (46.5%) were male and female, respectively. Also, 74 (46.5%), and 84 (53.5%) of EPTB were from Iran, and Afghanistan immigrants, respectively. The average age of patients was 41.9±2.18. Among underlying diseases in extrapulmonary TB positive, diabetes mellitus (DM) was predominant with a prevalence of 31 (19.5%), while, 128 (80.5%) cases did not show any underlying disease. Most of the patients were in the age group (21-40 years) with a frequency of 60 (37.7%), and the lowest of patients belonged to the age group (>80 years) with a frequency of 9 (5.7%). No correlation was found between related factors and infection with EPTB (p> 0.05). Conclusion: Our findings showed that the prevalence of EPTB in Kashan was relatively high, but, a relative decrease was shown during 2004-2017, which with preventative measures can be reduced the prevalence. [ABSTRACT FROM AUTHOR]

Aims: The use of automatic teller machines (ATMs) daily has increased the chances of hand-borne transmission of microorganisms to the machine's surfaces, and they can have an important role in microorganisms' transmission to individuals. This study aimed to investigate microbial contamination in ATMs in the center of Iran. Materials and Methods: This cross-sectional study was used to collect samples from the keyboards and monitors of the ATMs in Kashan. After 24 h of incubation, the swabs were inoculated on different selective media, including MacConkey agar and blood agar. Microbiological tests were used to confirm bacterial isolates. Results: The most frequently contaminated ATMs were government banks, with 69% contamination. The most frequently isolated bacterium was Staphylococcus epidermidis) 37/77%). The other bacteria were also identified, including Bacillus spp. (17/77%), Escherichia coli (7/77%), Micrococcus spp. (7/77%), Myroides odoratus (4/44%), Klebsiella pneumoniae (2/22%), Staphylococcus aureus (2/22%), Staphylococcus saprophyticus (1/11%), and Klebsiella oxytoca (1/11%), respectively. Conclusions: The most tested ATM keyboards in this study were contaminated with at least one microorganism. According to our results, it is recommendable to disinfect the hands after entering public places to hinder the spread of critical pathogens. [ABSTRACT FROM AUTHOR]

Objective(s): Klebsiella pneumoniae is the common cause of pneumonia in hospitalized patients, particularly in intensive care units (ICU). The infection can transfer by medical equipment such as mechanical ventilators. This study aimed to investigate the molecular typing of the extended-spectrum beta-lactamase-producing K. pneumoniae isolates recovered from Beheshti Hospital, Kashan, Iran. Materials and Methods: K. pneumoniae isolates producing ESBLs have been collected from the samples obtained from Shahid Beheshti hospital, Kashan, Iran. Antimicrobial susceptibility was determined using the Kirby Bauer disk diffusion method. The presence of ESBLs was evaluated using CLSI for ESBL screening by the double-disk diffusion method. Molecular typing was conducted by pulsed-field gel electrophoresis (PFGE). In total, 89 K. pneumoniae isolates were recovered, of which 47.1% were ESBL producers. Results: Results showed that all of the clinical and environmental isolates were resistant to ceftriaxone, meropenem, cefazolin, cefotaxime, cephalothin, and piperacillin-tazobactam. All isolates were grouped under four clusters (A-D). The major cluster was related to the C cluster with 22 isolates (19 clinical and 3 environmental). Seventy-two percent of isolates were from the ICU ward. There was no correlation between antibiotic resistance patterns and PFGE clusters (P=0.2). Conclusion: We observed a common molecular signature among both clinical and environmental K. pneumoniae isolates, indicating a similar genotype and likely a common origin for ESBL producer isolates found in different hospital wards. Therefore, hospitals need to implement an effective infection control system to decrease the spreading of ESBL strains within the hospitals and subsequently the transmission of the infection to patients. [ABSTRACT FROM AUTHOR]

Semiconductor heterogeneous photocatalysis has been received much attention from the scientific and researchers in the last decade. The combination of two semiconductors with various energy diagram can dramatically enhance the lifetime and separation of the charge carriers, restrain photogenerated electron‐hole recombination, and considerably enhance photocatalytic performance as compared with other single or binary components. In this regard, we introduced the Dy2BaCuO5/Ba4DyCu3O9.09 nanocomposites as active photocatalysts below UV radiation. Dy2BaCuO5/Ba4DyCu3O9.09 nanocomposites were prepared by a simple hydrothermal method and applied as a catalyst to treat water containing organic pollutions and microorganisms. Dy2BaCuO5/Ba4DyCu3O9.09 nanocomposites degraded Methyl Orange (MO) about 87.0% after 120 min. In addition, these nanocomposites show antimicrobial activity against Gram‐positive species, including a pathogenic strain of Enterococcus faecalis, and Staphylococcus aureus, and a Gram‐negative species, including Klebsiella pneumonia and Escherichia coli. [ABSTRACT FROM AUTHOR]

The result of infection of bone with microorganisms is osteomyelitis and septic arthritis. Methicillin-resistant Staphylococcus aureus (MRSA) is responsible for most of its cases (more than 50%). Since MRSA is resistant to many treatments, it is accompanied by high costs and numerous complications, necessitating more effective new treatments. Recently, development of gelatin nanoparticles have attracted the attention of scientists of biomedicine to itself, and have been utilized as a delivery vehicle for antibiotics because of their biocompatibility, biodegradability, and cost-effectiveness. Promising results have been reported with gelatin modification and combinations with chemical agents. Although these findings have been suggested that gelatin has the potential to be a suitable option for continuous release of antibiotics in osteomyelitis and septic arthritis treatment, they still have not become routine in clinical practices. The most deliver antibiotic using gelatin-derived composites is vancomycin which is showed the good efficacy. To date, a number of pre-clinical studies evaluated the utility of gelatin-based composites in the management of osteomyelitis. Gelatin-based composites were found to have satisfactory performance in the control of infection, as well as the promotion of bone defect repair in chronic osteomyelitis models. This review summarized the available evidence which provides a new insight into gelatin-derived composites with controlled release of antibiotics., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Sherafati Chaleshtori, Marzhoseyni, Saeedi, Azar Bahadori, Mollazadeh, Pourghadamyari, Sajadimoghadam, Abbaszadeh‐Goudarzi, Moradi Hasan-Abad and Sharafati Chaleshtori.)

Gastrointestinal (GI) cancer is a major health concern due to its prevalence, impact on well-being, high mortality rate, economic burden, and potential for prevention and early detection. GI cancer research has made remarkable strides in understanding biology, risk factors, and treatment options. An emerging area of research is the gut microbiome's role in GI cancer development and treatment response. The gut microbiome, vital for digestion, metabolism, and immune function, is increasingly linked to GI cancers. Dysbiosis and alterations in gut microbe composition may contribute to cancer development. Scientists study how specific bacteria or microbial metabolites influence cancer progression and treatment response. Modulating the gut microbiota shows promise in enhancing treatment efficacy and preventing GI cancers. Gut microbiota dysbiosis can impact GI cancer through inflammation, metabolite production, genotoxicity, and immune modulation. Microbes produce metabolites like short-chain fatty acids, bile acids, and secondary metabolites. These affect host cells, influencing processes like cell proliferation, apoptosis, DNA damage, and immune regulation, all implicated in cancer development. This review explores the latest research on gut microbiota metabolites and their molecular mechanisms in GI cancers. The hope is that this attempt will help in conducting other relevant research to unravel the precise mechanism involved, identify microbial signatures associated with GI cancer, and develop targets., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)