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Transmission of extended-spectrum β-lactamases-producing (ESBL) Escherichia coli from meat and meat by-products to humans has emerged as a major public health issue, requiring a One Health framework to address this menace. Hence, we investigated the phylotypes, antimicrobial resistance profiles, and virulotypes of E. coli isolates from chicken meat, beef burger, and human stool samples, besides investigating the in vitro antimicrobial and antivirulence efficacies of liposomal cinnamon, oregano, and clove essential oils (LCOC). A total of 90 isolates (28.1%) were phenotypically and molecularly identified as E. coli, and they were classified into four phylogenetic groups: B1, B2, A, and D (40, 35.6, 14.4, and 10%, respectively). The majority of the isolates were multidrug-resistant (MDR) (97.8%), with remarkable resistance against ampicillin, tetracycline, and cefotaxime (95.6, 84.4, and 81.1%, respectively). The blaTEM, tetA, aadA1, and blaCTX-M were the most prevalent resistance genes (96.7, 85.6, 81.1, and 81.1%, respectively). Virulotyping revealed that 70% of the isolates were multi-virulent, with iroN being the most prevalent one (92.2%). LCOC demonstrated in vitro antibacterial and antivirulence properties via inhibiting the growth of MDR, multi-virulent, and ESBL meat E. coli isolates and downregulating the expression of their investigated virulence genes. Concisely, the observed 28.1% prevalence of ESBL-producing E. coli indicates a notable public health concern associated with meat contamination. Our findings demonstrate that LCOC exhibited antimicrobial activity against the tested E. coli isolates and may help reduce their antibiotic resistance and virulence potential.

Listeriosis is a severe zoonotic disease caused by Listeria monocytogenes ( L. monocytogenes ), which can be acquired through animal source foods. This pathogen shows unique virulence fitness allowing it to penetrate and survive inside host cells causing extremely dangerous symptoms. Therefore, we aimed to correlate the clinical outcomes with the antimicrobial resistance and virulence profiles of L. monocytogenes . This is crucial for improving disease management, developing new therapeutic strategies, enhancing public health and food safety, and advancing scientific knowledge. Therefore, we assessed the antimicrobial resistance and virulence profiles of L. monocytogenes isolated from various sources, along with their potential to cause disease, using an in vivo rabbit model. Based on identification criteria, 47 L. monocytogenes isolates (15.7%) were recovered with the highest detection rates among rabbits (22%). Unfortunately, all the investigated isolates showed multidrug resistance (MDR) as well as multi-virulent profiles with 45 highly heterogeneous clusters. Noteworthy, the degree of illnesses of the experimentally infected rabbits was dependent on the virulence profiles. Specific nervous manifestations and severe histopathological alterations were observed in experimental rabbits infected with highly virulent isolates confirming that the potential ability of this pathogen to produce a disease is not always decipherable from its virulence arrays. Finally, it was confirmed that managing infections caused by L. monocytogenes has become increasingly challenging due to its high antimicrobial resistance, strong virulence, and the severe pathological effects linked to its virulence factors.

In most cell types and heterologous expression systems, the electrogenic sodium-bicarbonate cotransporter NBCe1 operates with a 1Na+–2HCO3− stoichiometry that, given typical transmembrane electrochemical gradients, promotes Na+ and HCO3− influx. However, NBCe1 in the kidney mediates HCO3− efflux (HCO3− reabsorption), a direction that has been predicted to be favored only if NBCe1 operates with a 1:3 stoichiometry. The phosphorylation state of Ser982 in the cytosolic carboxy-terminal domain of NBCe1 has been reported to be a key determinant of the transporter stoichiometry, with non-phosphorylated Ser982 favoring a 1:3 stoichiometry. Conversely, phosphoproteomic data from renal cortical preparations have revealed the presence of NBCe1 peptides including phosphoserine982 (pSer982) and/or pSer985 although it was not known what proportion of NBCe1 molecules were phosphorylated. In the present study, we report the generation, characterization, and application of a novel phosphospecific antibody raised against NBCe1/pSer982 and show that, contrary to expectations, Ser982 is more prevalently phosphorylated in murine kidneys (in which NBCe1 mediates HCO3− efflux) than in murine colons (in which NBCe1 mediates HCO3− influx). Using phosphomimetic mutants of murine NBCe1 expressed in Xenopus oocytes, we found no evidence that the phosphorylation state of Ser982 or Ser985 alone influences the transport stoichiometry or conductance. Furthermore, we found that the phosphorylation of NBCe1/Ser982 is enhanced in murine kidneys following a 24 h induction of metabolic acidosis. We conclude that the phosphorylation status of Ser982 is not a key determinant of NBCe1 stoichiometry but correlates with presumed NBCe1 activity.

In most cell types and heterologous expression systems, the electrogenic sodium-bicarbonate cotransporter NBCe1 operates with a 1Na -2HCO stoichiometry that, given typical transmembrane electrochemical gradients, promotes Na+ and HCO influx. However, NBCe1 in the kidney mediates HCO efflux (HCO reabsorption), a direction that has been predicted to be favored only if NBCe1 operates with a 1:3 stoichiometry. The phosphorylation state of Ser982 in the cytosolic carboxy-terminal domain of NBCe1 has been reported to be a key determinant of the transporter stoichiometry, with non-phosphorylated Ser982 favoring a 1:3 stoichiometry. Conversely, phosphoproteomic data from renal cortical preparations have revealed the presence of NBCe1 peptides including phosphoserine982 (pSer982) and/or pSer985 although it was not known what proportion of NBCe1 molecules were phosphorylated. In the present study, we report the generation, characterization, and application of a novel phosphospecific antibody raised against NBCe1/pSer982 and show that, contrary to expectations, Ser982 is more prevalently phosphorylated in murine kidneys (in which NBCe1 mediates HCO efflux) than in murine colons (in which NBCe1 mediates HCO influx). Using phosphomimetic mutants of murine NBCe1 expressed in oocytes, we found no evidence that the phosphorylation state of Ser982 or Ser985 alone influences the transport stoichiometry or conductance. Furthermore, we found that the phosphorylation of NBCe1/Ser982 is enhanced in murine kidneys following a 24 h induction of metabolic acidosis. We conclude that the phosphorylation status of Ser982 is not a key determinant of NBCe1 stoichiometry but correlates with presumed NBCe1 activity.

IntroductionPolycystic ovary syndrome (PCOS) is a common endocrine disorder among women of reproductive age. This study aimed to determine self-reported prevalence of physician-diagnosed PCOS among young medical students at King Saud University and to compare it with reported rates from Western and international populations of similar age. In addition, it assessed the awareness among female medical students at King Saud University.MethodsA cross-sectional study was conducted using a structured self-administered questionnaire distributed to female medical students at King Saud University between December 2024 and March 2025. The survey contained sociodemographic data, PCOS-related signs and symptoms, past medical history, lifestyle factors, knowledge about PCOS and its complications. Statistical analyses included bivariate analysis and multivariable logistic regression.ResultsWe collected 303 responses. The self-reported prevalence of physician-diagnosed PCOS was 18.5%. Common symptoms included hair loss (60.7%), acne (49.8%), and weight gain (32%). PCOS diagnosis was significantly associated with age group (p = 0.015), BMI (p = 0.038), menstrual irregularities (p < 0.001), hirsutism (p < 0.001), weight gain (p = 0.004), diabetes mellitus (p < 0.001), and family history (p < 0.001). Multivariable logistic regression identified hirsutism (OR = 4.36, p = 0.005) to be significantly associated with self-reported physician-diagnosed PCOS.ConclusionThe observed prevalence in young medical students in this study was higher than that reported in several Western populations of similar age. Recognition of contributing factors such as genetic susceptibility and lifestyle patterns is essential. Greater emphasis on early screening and targeted health education is recommended.

The COVID-19 pandemic accelerated a sudden transition to e-learning, creating challenges for nursing education, which relies heavily on clinical and practical training. This study examined male nursing students’ fear of COVID-19, their e-learning readiness, and the relationship between these variables in Saudi Arabia. A cross-sectional survey was conducted among 110 male nursing students from multiple Saudi universities. Data were collected using the Fear of COVID-19 Scale (FCoV-19 S) and an e-learning readiness questionnaire covering five domains. Descriptive statistics, Cronbach’s alpha reliability testing, Rasch logit transformation, Pearson’s correlation, and multiple linear regression were performed. The mean Fear of COVID-19 score was 21.7 ± 6.3 (α = 0.86). The mean overall e-learning readiness score was 112.5 ± 18.7 (α = 0.962), with the highest subscale scores in computer self-efficacy and motivation, and the lowest in online communication. Fear of COVID-19 demonstrated a significant negative correlation with e-learning readiness ( r = − 0.34, p  < 0.01). Regression analysis confirmed that fear of COVID-19 was a significant negative predictor of readiness (β = − 0.31, p  = 0.002), explaining 12% of the variance. Fear of COVID-19 had a measurable negative impact on e-learning readiness among Saudi nursing students, particularly affecting motivation and self-directed learning. Although internal reliability of the instruments was excellent, formal cultural validation procedures were not conducted. As the sample included only male participants, generalizability is limited. Institutions should integrate psychological support, skill-building strategies, and enhanced digital infrastructure to strengthen readiness for future academic disruptions.

The mammalian Na+/HCO3- cotransporter (NBCe1, encoded by the SLC4A4 gene) is a widely expressed membrane protein that regulates extracellular and intracellular pH. SLC4A4 makes two NBCe1 isoforms. NBCe1-A is expressed in the proximal tubule cells that facilitates reabsorption of ~80% of the filtered bicarbonate. NBCe1-B which is expressed in the colon promotes HCO3- secretion to hydrate the intestinal lumen.Although NBCe1 is known to be under hormonal control, the signaling pathways that regulate NBCe1 are not well understood. Therefore, I aim to assess the phosphorylation state of serine 982 in the kidney and compare it to the phosphorylation in the colon in vivo.The purpose of this thesis is to probe the state of phosphorylation of serine 982 residue (PKA consensus site) in NBCe1 in vivo. For that reason, a polyclonal phosphospecific peptide antibody was generated against PKA consensus site. Phosphospecificity of the antibody was established by western blot assays. I then used these antibodies to assess the effect of external stimuli (metabolic acidosis and secretagogues, forskolin, carbachol) on phosphorylation of serine 982 in NBCe1 endogenously expressed in kidney and colon mice cells and assess also the effect of and ANGII) on phosphorylation of serine 982 in NBCe1 exogenously expressed in heterologously system.I determined that serine 982 is phosphorylated to a much greater extent in mouse kidneys than in mouse colon in vivo under unstimulated conditions. Furthermore, I therefore tested whether external stimuli, 24 hr of chronic metabolic acidosis (CMA), 20 minutes of carbachol or forskolin, and 20 minutes of ANGII, affects the total NBCe1 in kidney and colon and the phosphorylation state of serine 982 in mice kidney and colon. I found that 24 hr of 0.28M NH4Cl does not change total NBCe1 and its PS982 in kidney nor colon. On the other hand, 20 minutes of 0.1% carbachol causes significant increase in total NBCe1 and significant decrease in phosphorylation state of ser982 in the colon. 20 minutes of 0.1% forskolin causes significant increase in the PS982 but non-significant increase in total NBCe1 in the colon. In heterologous system, 20 minutes of 10-6M ANGII causes decrease surface expression of NBCe1 under zoe microscope and there is no change in the surface expression of mutant NBCe1 S982A. On the other hand, in the biotinylation experiment.Taken together, PS982 of NBCe1 plays a role in its subcellular trafficking in vivo and in vitro. I have characterized the first NBCe1-phosphospecific antibody that should be useful to examine the phosphorylation state of endogenous NBCe1 at Ser982 under a variety of external stimuli in vitro and in vivo.