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Antibiotic-resistant microorganisms are a rising issue when it comes to human health. Microbial pathogens that cause harmful infections are quickly becoming resistant to the antimicrobial action of traditional antibiotics. Nanotechnology, an innovative sector being an indispensable part of healthcare and research, has in-depth and extensive applications. Nano-compounds have been promising antimicrobial agents, anti-cancerous mediators, vehicles for drug delivery, formulations for functional foods, identification of pathogens, food and drug packaging industry, and many more. However, the chemical synthesis of nanoparticles (NPs) has certain drawbacks such as causing toxicity and other adverse effects. For more than a decade, the use of NPs that are conjugated or green-synthesized has gained popularity due to the two-fold action of metallic NPs mixed with biological sources. In contrast, NPs synthesized using plant or microbial extracts, conjugated with biologically active components, appear to be a safe alternative approach as they are environmentally friendly and cost-effective. Such environmentally safe techniques are referred to as “green nanotechnology” or “clean technology” and are feasible alternatives to chemical methods. Furthermore, NPs conjugated with natural biomolecules have improved bioavailability and have minimal side effects, as they are smaller in size and have higher permeability in addition to being reducing and stabilizing agents possessing excellent antioxidant activity. NPs serve as potential antimicrobial agents due to their affinity towards sulphur-rich amino acids, adhere to microbial cell walls by means of electrostatic attraction, and disrupt the cytoplasmic membrane along with the nucleic acid of microbes. They possess anticancer activity owing to oxidative stress, damage to cellular DNA, and lipid peroxidation. The green-synthesized NPs are thus a promising and safe alternative for healthcare therapeutic applications.

This study investigated the chemotherapeutic effects of 5‐fluorouracil (5‐FU), metformin (Met), and/or thymoquinone (TQ) single/dual/triple therapies in the HT29, SW480 and SW620 colon cancer (CRC) cell lines. Cell cycle/apoptosis were measured by flow cytometry. The gene and protein expression of apoptosis (PCNA/survivin/BAX/Cytochrome‐C/Caspase‐3) and cell cycle (CCND1/CCND3/p21/p27) molecules, the PI3K/mTOR/HIF1α oncogenic pathway, and glycolysis regulatory enzymes were measured by quantitative‐PCR and Western blot. Markers of oxidative stress were also measured by colorimetric assays. Although all treatments induced anti‐cancer effects related to cell cycle arrest and apoptosis, the triple therapy showed the highest pro‐apoptotic actions that coincided with the lowest expression of CCND1/CCND3/PCNA/survivin and the maximal increases in p21/p27/BAX/Cytochrome‐C/Caspase‐3 in all cell lines. The triple therapy also revealed the best suppression of the PI3K/mTOR/HIF1α pathway by increasing its endogenous inhibitors (PTEN/AMPKα) in all cell lines. Moreover, the lowest expression of lactate dehydrogenase and pyruvate dehydrogenase kinase‐1 with the highest expression of pyruvate dehydrogenase were seen with the triple therapy, which also showed the highest increases in oxidative stress markers (ROS/RNS/MDA/protein carbonyl groups) alongside the lowest antioxidant levels (GSH/CAT) in all cell lines. In conclusion, this is the first study to reveal enhanced anti‐cancer effects for metformin/thymoquinone in CRC that were superior to all monotherapies and the other dual therapies. However, the triple therapy approach showed the best tumoricidal actions related to cell cycle arrest and apoptosis in all cell lines, possibly by enhancing oxidative glycolysis and augmenting oxidative stress through stronger modulation of the PI3K/mTOR/HIF1α oncogenic network. [ABSTRACT FROM AUTHOR]

Neisseria meningitidis is the most frequent cause of bacterial meningitis and is one of the few bacterial pathogens that can breach the blood-brain barrier (BBB). The 37/67 kDa laminin receptor (LamR) was previously identified as a receptor mediating meningococcal binding to rodent and human brain microvascular endothelial cells, which form part of the BBB. The meningococcal surface proteins PorA and PilQ were identified as ligands for this receptor. Subsequently, the fourth extracellular loop of PorA (PorA-Loop4) was identified as the LamR-binding moiety. Here, we show that PorA-Loop4 targets the 37 kDa laminin receptor precursor (37LRP) on the cell surface by demonstrating that deletion of this loop abrogates the recruitment of 37LRP under meningococcal colonies. Using a circularized peptide corresponding to PorA-Loop4, as well as defined meningococcal mutants, we demonstrate that host cell interaction with PorA-Loop4 results in perturbation of p-CDK4 and Cyclin D1. These changes in cell cycle control proteins are coincident with cellular responses including inhibition of cell migration and a G1 cell cycle arrest. Modulation of the cell cycle of host cells is likely to contribute to the pathogenesis of meningococcal disease. [ABSTRACT FROM AUTHOR]

Simple Summary: Failure of chemotherapy is common during the treatment of colon cancer, and there is a compelling need to develop alternative therapeutic approaches against this common malignancy. Metformin, which is an oral hypoglycaemic agent used for treating diabetes mellitus, and vitamin D have shown promising anticancer activities, and both agents boosted the actions of chemotherapy against colon cancer. This study, therefore, measured the potential beneficial effects of adding metformin and/or active vitamin D to the main cytotoxic drug used for treating colon cancer. The results demonstrate that metformin had superior anticancer effects relative to active vitamin D and ameliorated the effects of chemotherapy in animals and in cells. To the best of our knowledge, this study is also the first to report that triple treatment with the drugs of interest showed the best inhibition of cancer progression, which could provide a better therapeutic strategy against colon cancer. Chemoresistance to 5-fluorouracil (5-FU) is common during colorectal cancer (CRC) treatment. This study measured the chemotherapeutic effects of 5-FU, active vitamin D3 (VD3), and/or metformin single/dual/triple regimens as complementary/alternative therapies. Ninety male mice were divided into: negative and positive (PC) controls, and 5-FU, VD3, Met, 5-FU/VD3, 5-FU/Met, VD3/Met, and 5-FU/VD3/Met groups. Treatments lasted four weeks following CRC induction by azoxymethane. Similar regimens were also applied in the SW480 and SW620 CRC cell lines. The PC mice had abundant tumours, markedly elevated proliferation markers (survivin/CCND1) and PI3K/Akt/mTOR, and reduced p21/PTEN/cytochrome C/caspase-3 and apoptosis. All therapies reduced tumour numbers, with 5-FU/VD3/Met being the most efficacious regimen. All protocols decreased cell proliferation markers, inhibited PI3K/Akt/mTOR molecules, and increased proapoptotic molecules with an apoptosis index, and 5-FU/VD3/Met revealed the strongest effects. In vitro, all therapies equally induced G1 phase arrest in SW480 cells, whereas metformin-alone showed maximal SW620 cell numbers in the G0/G1 phase. 5-FU/Met co-therapy also showed the highest apoptotic SW480 cell numbers (13%), whilst 5-FU/VD3/Met disclosed the lowest viable SW620 cell percentages (81%). Moreover, 5-FU/VD3/Met revealed maximal inhibitions of cell cycle inducers (CCND1/CCND3), cell survival (BCL2), and the PI3K/Akt/mTOR molecules alongside the highest expression of cell cycle inhibitors (p21/p27), proapoptotic markers (BAX/cytochrome C/caspase-3), and PTEN in both cell lines. In conclusion, metformin monotherapy was superior to VD3, whereas the 5-FU/Met protocol showed better anticancer effects relative to the other dual therapies. However, the 5-FU/VD3/Met approach displayed the best in vivo and in vitro tumoricidal effects related to cell cycle arrest and apoptosis, justifiably by enhanced modulations of the PI3K/PTEN/Akt/mTOR pathway. [ABSTRACT FROM AUTHOR]

Abstract Background Post-translational modifications (PTMs) of histones and other proteins are perturbed in tumours. For example, reduced levels of acetylated H4K16 and trimethylated H4K20 are associated with high tumour grade and poor survival in breast cancer. Drug-like molecules that can reprogram selected histone PTMs in tumour cells are therefore of interest as potential cancer chemopreventive agents. In this study we assessed the effects of the phytocompounds garcinol and curcumin on histone and p53 modification in cancer cells, focussing on the breast tumour cell line MCF7. Methods Cell viability/proliferation assays, cell cycle analysis by flow cytometry, immunodetection of specific histone and p53 acetylation marks, western blotting, siRNA and RT-qPCR. Results Although treatment with curcumin, garcinol or the garcinol derivative LTK-14 hampered MCF7 cell proliferation, differential effects of these compounds on histone modifications were observed. Garcinol treatment resulted in a strong reduction in H3K18 acetylation, which is required for S phase progression. Similar effects of garcinol on H3K18 acetylation were observed in the osteosarcoma cells lines U2OS and SaOS2. In contrast, global levels of acetylated H4K16 and trimethylated H4K20 in MCF7 cells were elevated after garcinol treatment. This was accompanied by upregulation of DNA damage signalling markers such as γH2A.X, H3K56Ac, p53 and TIP60. In contrast, exposure of MCF7 cells to curcumin resulted in increased global levels of acetylated H3K18 and H4K16, and was less effective in inducing DNA damage markers. In addition to its effects on histone modifications, garcinol was found to block CBP/p300-mediated acetylation of the C-terminal activation domain of p53, but resulted in enhanced acetylation of p53K120, and accumulation of p53 in the cytoplasmic compartment. Finally, we show that the elevation of H4K20Me3 levels by garcinol correlated with increased expression of SUV420H2, and was prevented by siRNA targeting of SUV420H2. Conclusion In summary, although garcinol and curcumin can both inhibit histone acetyltransferase activities, our results show that these compounds have differential effects on cancer cells in culture. Garcinol treatment alters expression of chromatin modifying enzymes in MCF7 cells, resulting in reprogramming of key histone and p53 PTMs and growth arrest, underscoring its potential as a cancer chemopreventive agent.

Background: Group B Streptococcus (GBS) comprises the normal flora of the female urogenital tract and can be transferred to neonates during delivery, causing invasive diseases. This study was performed to investigate the colonization rate, antibiotic susceptibility, and serotype of GBS among Saudi pregnant women. Materials and Methods: In this cross-sectional study, vagino-rectal swabs from 400 pregnant women were collected over a period of one year. Identification of GBS isolates and determination of their antibiotic susceptibility were performed using the Microscan Walk Away system. The isolates were then typed using both latex agglutination and capsular genebased multiplex polymerase chain reaction assays. Results: Sixty (15.0%) subjects were colonized by GBS, with serotype Ia as the dominant type (30.0%) followed by serotype III and V (25.0%, each). Only 43 (71.7%) isolates were typed by latex agglutination, whereas the remaining isolates were not typable or were non-specifically typed as compared to the genotyping assay, which revealed the specific type of each GBS isolate. The highest resistance rates were observed for erythromycin and clindamycin (16.7%, each), which were mainly restricted to the prevalent serotypes. Conclusion: This study is the first to report the distribution of GBS serotypes based on molecular genotyping in Saudi Arabia. GBS colonization was evident among pregnant women, and resistance to erythromycin and clindamycin was predominant among serotypes Ia, III, and V. Molecular genotyping using capsular gene-based multiplex PCR provided reliable typing of the investigated GBS isolates in terms of sensitivity and specificity as compared to conventional serotyping using latex agglutination. [ABSTRACT FROM AUTHOR]

Although single treatment with sodium‐glucose cotransporter‐2 inhibitors (SGLT2i) or vitamin D3 (VD3) inhibited metabolic dysfunction‐associated steatohepatitis (MASH) development in diabetic patients, their combination has not been explored previously. Hence, this study investigated the hepatoprotective effects of SGLT2i (empagliflozin) and/or VD3 against MASH in type 2 diabetic mice. Forty Mice were assigned into negative (NC) and positive (PC) controls, SGLT2i, VD3, and SGLT2i + VD3 groups. All animals, except the NC group, received high‐fructose/high‐fat diet (8 weeks) followed by diabetes induction. Diabetic mice then received another cycle of high‐fructose/high‐fat diet (4 weeks) followed by 8 weeks of treatment (five times/week) with SGLT2i (5.1 mg/kg/day) and/or VD3 (410 IU/Kg/day). The PC group demonstrated hyperglycaemia, dyslipidaemia, elevated liver enzymes, and increased non‐alcoholic fatty liver disease activity score (NAS) with fibrosis. Hepatic glucose transporting molecule (SGLT2) with lipogenesis (SREBP‐1/PPARγ), oxidative stress (MDA/H2O2), inflammation (IL1β/IL6/TNF‐α), fibrosis (TGF‐β1/α‐SMA), and apoptosis (TUNEL/Caspase‐3) markers alongside the PI3K/AKT/mTOR pathway increased in the PC group. Conversely, hepatic insulin‐dependent glucose transporter (GLUT4), lipolytic (PPARα/INSIG1), antioxidant (GSH/GPx1/SOD1/CAT), and anti‐inflammatory (IL‐10) molecules with the inhibitor of PI3K/AKT/mTOR pathway (PTEN) decreased in the PC group. Whilst SGLT2i monotherapy outperformed VD3, their combination showed the best attenuation of hyperglycaemia, dyslipidaemia, and fibrosis with the strongest modulation of hepatic glucose‐transporting and lipid‐regulatory molecules, PI3K/AKT/mTOR pathway, and markers of oxidative stress, inflammation, fibrosis, and apoptosis. This study is the first to reveal boosted hepatoprotection for SGLT2i and VD3 co‐therapy against diabetes‐induced MASH, possibly via enhanced metabolic control and modulation of hepatic PI3K/AKT/mTOR, anti‐inflammatory, anti‐oxidative, and anti‐fibrotic pathways. [ABSTRACT FROM AUTHOR]

Introduction: Blood donation is vital for healthcare; however, transfusion-transmitted infections (TTIs) pose a serious risk. This study investigated the seroprevalence of TTIs among Saudi blood donors. Methodology: This retrospective study included male blood donors aged ≥ 18 years who donated blood at Al-Noor Specialist Hospital in Makkah from January 2017 to December 2022. The blood units were screened for hepatitis B surface antigen (HBsAg) and core antibodies (HBc-IgG), hepatitis C antibodies (HCV-Abs), syphilis, HIV-1 antigen/antibody (HIV-1 Ag/Ab), human T-lymphotropic virus 1, 2 (HTLV1/2), and malaria. Results: There were 40,287 donors with an average age of 44.33 ± 18.12 years, and 62.3% (n = 25103) were Saudis. The overall rate of TTIs seropositivity was 7.4% (n = 2953); HBc-IgG (6.1%; n = 2473) was the most common, followed by HCV-Abs (0.4%; n = 177), and syphilis (0.34%; n = 136). All cases were negative for malaria, whilst HIV and HTLV positive donors were 0.06% (n = 24) and 0.13% (n = 52), respectively. Syphilis was more prevalent among non-Saudis (0.24%; n = 83) than among Saudis (0.1%; n = 53), whereas anti-HBc antibodies seropositivity was significantly higher among Saudi (3.4%; n = 1373) than non-Saudi donors (2.7%; n = 1100). Conclusions: Hepatitis B virus was the most frequently detected bloodborne pathogen, followed by hepatitis C virus and syphilis. Hepatitis B virus was also more prevalent among Saudi donors, whilst expatriates had higher rates of syphilis. Additional prospective multicenter studies are needed to accurately determine the prevalence of TTIs in Saudi Arabia. [ABSTRACT FROM AUTHOR]