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Background: Aflatoxin (AF), a metabolite of Aspergillus flavus, is injurious to vital body organs. The bacterial defense against such mycotoxins has attracted significant attention. Lactic acid bacteria (LAB) are known to ameliorate AF toxicity. Methods: Thirty adult male rats were divided into six groups (five each) to perform the experiments. The control (Co) group was fed a basal diet and water. Each of the following periods lasted 21 days: the milk (MK) group orally received milk (500 µL); LAB suspension (500 µL) containing 107 cfu/mL was orally provided to the LAB group; AF (0.5 mg/kg) was orally given to the AF group; and a combination of AF and LAB was administered to the AF + LAB group. The AF/LAB group was initially given AF for 21 days, followed by LAB for the same period. Finally, the rats were dissected to retrieve blood and tissue samples for hematological, biochemical, and histological studies. Results: The results revealed a significant decrease in RBCs, lymphocytes, total proteins, eosinophil count, albumin, and uric acid, whereas the levels of WBCs, monocytes, neutrophils, creatinine, urea, aspartate aminotransferase, alkaline phosphatase, alanine aminotransferase, lactate dehydrogenase, and creatinine kinase significantly increased in the AF group in comparison to the control group. The histological examination of the AF group revealed necrosis and apoptosis of the kidney's glomeruli and renal tubules, nuclei vacuolization and apoptosis of hepatocytes, congestion of the liver's dilated portal vein, lymphoid depletion in the white pulp, localized hemorrhages, hemosiderin pigment deposition in the spleen, and vacuolization of seminiferous tubules with a complete loss of testis spermatogenic cells. Meanwhile, protective and therapeutic LAB administration in AF-treated rats improved the hematological, biochemical, and histological changes. Conclusions: The study revealed LAB-based amelioration to AFB1-induced disruptions of the kidney, liver, spleen, and testis by inhibiting tissue damage. The therapeutic effects of LAB were comparatively more pronounced than the protective effects. [ABSTRACT FROM AUTHOR]

Hospital acquired-Staphylococcus aureus (HA-Staphylococcus aureus), particularly methicillin-resistant Staphylococcus aureus (MRSA), are an important source of nosocomial infections with high morbidity and mortality rates. Few reports showed that infections due to HA-Staphylococcus aureus in Saudi Arabia is increasing, particularly infections attributed to HA-MRSA. The study aimed to explore the prevalence and clinical characteristics of HA-Staphylococcus aureus for the first time in Medina, Saudi Arabia. A total of 1262 clinical samples of hospitalized patients were examined for the presence of Staphylococcus aureus through selective culturing on mannitol salt agar. Vitek Compact System and conventional methods were followed to confirm the isolates. Vitek Compact System tested the antimicrobial susceptibility of isolates whereas the standard PCR was employed to detect the genes encoding antimicrobial resistance (mecA and vanA) and virulence factors (tst, et, and LukS-PV). The overall HA-Staphylococcus aureus prevalence was low (6.58%, n = 1262) of which 84.34% (n = 83) were MRSA. Approximately, 57 samples of the 70 MRSA (81.5%) exhibited a multidrug-resistance (MDR) pattern. All the 83 HA-Staphylococcus aureus isolates were negative for the genes encoding toxic shock syndrome toxin, exfoliative toxin, and Panton-Valentine leukocidin. The study was conducted during the Covid-19 pandemic under partial lockdown, restricted hospitalization, and increased disinfection and infection control measures. Therefore, the low prevalence of HA-Staphylococcus aureus should be carefully interpreted and further multicenter investigations could reveal its true incidence in the city. The high prevalence of MDR HA-MRSA is alarming as it highlights inappropriate antibiotic prescriptions to counter staphylococcal infections. HA-Staphylococcus aureus investigated in this study might lack certain virulence factors. However, their MDR traits and invasive nature could worsen the situation if not properly handled. [ABSTRACT FROM AUTHOR]

We report in this study for the first time the prevalence of multiple resistant Staphylococcus haemolyticus in clinical settings in Saudi Arabia. A total of 1060 clinical specimens of hospitalized patients were screened for the presence of S. haemolyticus in the period between September and December 2020. Primary identification of the isolates was carried out by colonial characteristics on mannitol salt agar and clumping factor test, confirmation of presumptive isolates and antimicrobial susceptibility testing was performed by Vitek® 2, while PCR was employed to detect mecA and vanA genes. A total of 20 S. haemolyticus isolates were recovered from 20 samples (blood cultures, urine, nasal swab, wound swab, groin swab, and axilla swab), 90% (P <0.001, x2) of the isolates were multiple resistant to three antimicrobial agents and more. Resistance to oxacillin was exhibited in 95% of the isolates, while none of the isolates were resistant to vancomycin and linezolid, yet resistance to rifampicin was observed in 30 % of the isolates. The findings of this study highlights the emerging trends of Staphylococcus haemolyticus as potential drug resistant pathogen in hospital settings in Saudi Arabia, which requires in depth investigation on molecular understanding on antimicrobial resistance and virulence traits of the strains. [ABSTRACT FROM AUTHOR]