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Gold nanoparticles (AuNPs) are widely recognized for their remarkable optical and chemical properties, making them versatile materials with diverse applications in sensing, catalysis, and biomedical fields. However, their susceptibility to aggregation and poor dispersion under different environmental stresses limits their utility in practical applications. In this study, we investigate the efficacy of utilizing carboxylate-terminated ligands to stabilize AuNPs and enhance their stability and functionality. Through a series of experiments, including assessments of pH buffer effects, ionic strength variations, freeze-drying stress, and protein adsorption, we demonstrate the effectiveness of these ligands in maintaining the stability of AuNPs within a pH range of 5–10. This enables them to resist aggregation in the presence of high concentrations of electrolytes and facilitates rapid redispersion after freeze-drying, enabling long-term storage of AuNPs in a dry powder form without compromising their stability or functionality. Moreover, the ligands efficiently prevent nonspecific protein binding. We explore application of these stabilized AuNPs conjugated with specific monoclonal antibodies for detection of Listeria monocytogenes, highlighting their potential for use in biosensing applications. This research underscores the significance of carboxylate-terminated ligands in stabilizing AuNPs, offering insights into the development of reliable and functional nanomaterials for various biomedical and biosensing applications. [ABSTRACT FROM AUTHOR]

Background: Infection with the Gram-negative bacterium Burkholderia pseudomallei is an important cause of community-acquired lethal sepsis in endemic regions in southeast Asia and northern Australia and is increasingly reported in other tropical areas. In animal models, production of interferon-gamma (IFN-gamma) is critical for resistance, but in humans the characteristics of IFN-gamma production and the bacterial antigens that are recognized by the cell-mediated immune response have not been defined. Methods: Peripheral blood from 133 healthy individuals who lived in the endemic area and had no history of melioidosis, 60 patients who had recovered from melioidosis, and 31 other patient control subjects were stimulated by whole bacteria or purified bacterial proteins in vitro, and IFN-gamma responses were analyzed by ELISPOT and flow cytometry. Findings: B. pseudomallei was a potent activator of human peripheral blood NK cells for innate production of IFN-gamma. In addition, healthy individuals with serological evidence of exposure to B. pseudomallei and patients recovered from active melioidosis developed CD4(+) (and CD8(+)) T cells that recognized whole bacteria and purified proteins LolC, OppA, and PotF, members of the B. pseudomallei ABC transporter family. This response was primarily mediated by terminally differentiated T cells of the effector-memory (T(EMRA)) phenotype and correlated with the titer of anti-B. pseudomallei antibodies in the serum. Conclusions: Individuals living in a melioidosis-endemic region show clear evidence of T cell priming for the ability to make IFN-gamma that correlates with their serological status. The ability to detect T cell responses to defined B. pseudomallei proteins in large numbers of individuals now provides the opportunity to screen candidate antigens for inclusion in protein or polysaccharide-conjugate subunit vaccines against this important but neglected disease.

A limited self‐healing ability of injured articular cartilage results in osteoarthritis and a joint dysfunction afterward. Cartilage tissue engineering is a promising approach to increase the treatment efficiency. Moreover, host response to implanted biomaterial has been increasingly concerned. Thus, this study aimed to establish three‐dimensional (3D) scaffold that could support cartilage tissue engineering and reduce inflammatory. The various ratios of silk fibroin (SF), gelatin (G), chondroitin sulfate (C), hyaluronic acid (H), and aloe vera (A) were used to fabricate 3D scaffolds by lyophilization, designated as SF, SF‐A, SF‐gelatin/chondroitin sulfate/hyaluronic acid (GCH)‐A‐411, and SF‐GCH‐A‐111. The physical and biological characteristics of the scaffolds were investigated. All scaffolds possessed interconnected porous structures, which the highest pore size of 209 μm was found in SF and SF‐GCH‐A‐411 scaffolds. Moreover, high porosity, high water uptake, and good mechanical strength were observed in the SF‐GCH‐A‐411 scaffold. The SF, SF‐A, and SF‐GCH‐A‐411 scaffolds could retain their structures up to 21 days, while SF‐GCH‐A‐111 was rapidly degraded. The proliferation of human bone marrow mesenchymal stem cells (BM‐MSCs) was significantly higher in SF‐A and SF‐GCH‐A‐411 than in the SF scaffold. Besides, the SF‐A and SF‐GCH‐A‐411 revealed significantly lower expression of pro‐inflammatory cytokine, interleukin‐1 beta than the SF scaffold, suggesting the beneficial role of aloe vera in anti‐inflammatory effect. Furthermore, the SF‐GCH‐A‐411 scaffold could support chondrogenic differentiation of BM‐MSCs. In conclusion, based on its superior physical and biological characteristics that support chondrogenesis of BM‐MSCs, the SF‐GCH‐A‐411 scaffold is recommended for cartilage tissue engineering. [ABSTRACT FROM AUTHOR]

In Thailand, chronic kidney disease (CKD) screening was reported in 2009 with an overall prevalence of 17.5% and the highest at 22.2% in the northeastern region. This study aimed to find out CKD prevalence of the Kidney Disease Improving Global Outcomes criteria and their related risk factors in the rural community. A population-based study was conducted in the rural sub-districts of northeastern Thailand. Data of socio-demographic status, lifestyle, underlying diseases, blood pressure, and body mass index were recorded. Blood and urine analysis was conducted along with ultrasonography of kidneys. Specimen collection and analyses were repeated after 3 months, and the factors associated with CKD were studied by logistic regression analysis. A total of 2205 participants with a mean age of 57.8 ± 11.7 years and female predominance (66.7%) completed the study. The prevalence of CKD was 26.8%, i.e., stages 1 (7.3%); stage 2 (9.0%); stage 3a (6.0%); stage 3b (2.8%); stage 4 (1.4%); and stage 5 (0.3%). Hypertension, diabetes mellitus, and renal stones were the major underlying diseases. Only 3.5% of the participants were aware of having CKD. An increase in age, male, unemployment, current smoking, diabetes, hypertension, underweight, anemia, hyperuricemia, and leukocytosis were significantly associated factors with the disease. The study revealed that CKD has developed as a significant public health problem in rural northeastern Thailand and one out of every four people has CKD. Therefore, early interventions are essential for the proper management and prevention of CKD. [ABSTRACT FROM AUTHOR]