Exploring antibiotic resistance mechanisms in Mycobacterium abscessus for enhanced therapeutic approaches.

Mycobacterium abscessus, a leading cause of severe lung infections in immunocompromised individuals, poses significant challenges for current therapeutic strategies due to resistance mechanisms. Therefore, understanding the intrinsic and acquired antibiotic resistance of M. abscessus is crucial for effective treatment. This review highlights the mechanisms employed by M. abscessus to sustain antibiotic resistance, encompassing not only conventional drugs but also newly discovered drug candidates. This comprehensive analysis aims to identify novel entities capable of overcoming the notorious resistance exhibited by M. abscessus, providing insights for the development of more effective therapeutic interventions.

Highly sensitive amperometric detection of cardiac troponin I using sandwich aptamers and screen-printed carbon electrodes.

In this study, we developed a sandwich aptamer-based screen-printed carbon electrode (SPCE) using chronoamperometry for the detection of cardiac troponin I (cTnI), one of the promising biomarkers for acute myocardial infarction (AMI). Disposable three-electrode SPCEs were manufactured using a screen printer, and various modifications such as electrodeposition of gold nanoparticles and electropolymerization of conductive polymers were performed. From the bare electrode to the aptamer-immobilized SPCE, all processes were monitored and analyzed via various techniques such as cyclic voltammetry, electrochemical impedance spectroscopy, and X-ray photoelectron spectroscopy. The quantification of cTnI was conducted based on amperometric signals from the catalytic reaction between hydrazine and H2O2. The fabricated aptasensor in a buffer, as well as in a serum-added solution, exhibited great analytical performance with a dynamic range of 1-100 pM (0.024-2.4ng/mL) and a detection limit of 1.0 pM (24pg/mL), which is lower than the existing cutoff values (40-700pg/mL). Furthermore, the developed sensor showed high sensitivity to cTnI over other proteins. It is anticipated that this potable SPCE aptasensor for cTnI will become an innovative diagnostic tool for AMI.

A highly sensitive and selective impedimetric aptasensor for interleukin-17 receptor A.

Interleukin-17 receptor A (IL-17RA) has been recognized as a valuable biomarker for diverse diseases, including autoimmune diseases. In this work, an electrochemical biosensor with great sensitivity and selectivity toward IL-17RA was fabricated using an IL-17RA aptamer (Kd=14.00nM) for the first time. The aptasensor was manufactured using electrodeposition of gold nanoparticles, and then quantitative detection of IL-17RA was performed based on impedimetry. The developed sensor exhibited a superior analytical performance for IL-17RA with a wide dynamic range of 10-10,000pg/mL in buffer and a detection limit of 2.13pg/mL, which is lower than that of commercially available ELISA kits. In addition, we validated the high specificity of the designed aptasensor to only IL-17RA, which showed good sensitivity even in human serum solution. Furthermore, the detection of the differentiated HL-60 cells expressing IL-17RA was successfully performed. Clinical applicability of the sensor was also demonstrated utilizing neutrophils separated from asthma patients. It is expected that the fabricated aptasensor will become an excellent diagnostic platform for IL-17RA-mediated diseases.

Clinical and microbial evaluation of the effects on gingivitis of a mouth rinse containing an Enteromorpha linza extract.

Enteromorpha linza, a green alga, has been recognized as a potential source of natural antimicrobial and antifungal compounds. We previously reported that an E. linza extract strongly inhibited the growth of Prevotella intermedia and Porphyromonas gingivalis. The principal objective of this study was to evaluate the clinical effect of a mouth rinse containing the E. linza extract on gingivitis disease, as measured by the plaque index (PI), gingival index (GI), and bleeding on probing (BOP), and on two bacterial strains (P. intermedia and P. gingivalis), in comparison with Listerine(®) (Listerine-Korea, Seoul, Korea), which was used as a positive control. In total, 55 subjects were recruited into active participation in this clinical study. The PI, GI, BOP, and bacterial strains were then evaluated over a test period of 6 weeks. After 1, 2, 4, and 6 weeks, the same clinical indices were recorded, and the levels of P. intermedia and P. gingivalis were quantified via real-time polymerase chain reaction. At the end of the study, the group using the mouth rinse containing the E. linza extract evidenced significant reductions in the clinical indices (PI, GI, and BOP) and P. gingivalis compared with baseline values. Moreover, E. linza extract containing mouth rinse produced effects similar to those of Listerine. Overall, these results indicate that a mouth rinse containing E. linza extract significantly reduces plaque, improves the condition of gingival tissues, and reduces bleeding. Additionally, E. linza extract mouth rinse significantly inhibits P. gingivalis and P. intermedia. Thus, this clinical study demonstrated that the twice-daily use of an E. linza extract mouth rinse can inhibit and prevent gingivitis.

Effect of ginsenosides Rg3 and Re on glucose transport in mature 3T3-L1 adipocytes.

Ginsenosides, the active component of Panax ginseng, have been shown to evidence a variety of biological activities associated with hyperglycemia, obesity and type 2 diabetes mellitus. This study evaluated the effects of the ginsenosides, Rg3 and Re, on glucose uptake and the glucose transport system in mature 3T3-L1 cells. The results demonstrated that the glucose uptake of ginsenosides Rg3 and Re at concentrations of 1-10 µM significantly increased by approximately ∼10% and ∼12%, respectively. Furthermore, the glucose transporter 4 (GLUT4) mRNA expression of ginsenosides Rg3 and Re at 10 µM was increased by approximately ∼1.73 and 1.43 fold, respectively. It was further confirmed in a series of experiments that ginsenosides Rg3 and Re stimulated the mRNA expression of insulin receptor substrate (IRS-1) and the expression of phosphatidylinositol 3-kinase (PI3K)-110α protein, which is involved in downstream events in the insulin signaling pathway. These findings demonstrate that ginsenosides Rg3 and Re may stimulate glucose uptake via the PI3K pathways involving IRS-1. Further, our results suggest that both of these ginsenosides might prove useful as effective antidiabetic and antihyperglycemic agents.

Effect of pycnogenol on glucose transport in mature 3T3-L1 adipocytes.

Pycnogenol, a procyanidins-enriched extract of Pinus maritima bark, possesses antidiabetic properties, which improves the altered parameters of glucose metabolism that are associated with type 2 diabetes mellitus (T2DM). Since the insulin-stimulated antidiabetic activities of natural bioactive compounds are mediated by GLUT4 via the phosphatidylinositol-3-kinase (PI3K) and/or p38 mitogen activated protein kinase (p38-MAPK) pathway, the effects of pycnogenol were examined on the molecular mechanism of glucose uptake by the glucose transport system. 3T3-L1 adipocytes were treated with various concentrations of pycnogenol, and glucose uptake was examined using a non-radioisotope enzymatic assay and by molecular events associated with the glucose transport system using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). The results show that pycnogenol increased glucose uptake in fully differentiated 3T3-L1 adipocytes and increased the relative abundance of both GLUT4 and Akt mRNAs through the PI3K pathway in a dose dependent manner. Furthermore, pycnogenol restored the PI3K antagonist-induced inhibition of glucose uptake in the presence of wartmannin, an inhibitor of the PI3K. Overall, these results indicate that pycnogenol may stimulate glucose uptake via the PI3K dependent tyrosine kinase pathways involving Akt. Further the results suggest that pycnogenol might be useful in maintaining blood glucose control.

A 4-week repeated oral dose toxicity study of fucoidan from the Sporophyll of Undaria pinnatifida in Sprague-Dawley rats.

Fucoidan is extracted from brown seaweeds, which can have anti-coagulant, antithrombotic, antitumor, and antiviral activities. However, detailed studies on the toxicology of fucoidan have not been performed. Here we tested the toxicity of fucoidan in Sprague-Dawley rats. Fucoidan (1350mg/kg bw/day for 4 weeks) did not induce statistically significant differences in groups matched by gender with respect to body weight, ophthalmoscopy, urinalysis, hematology, and histopathology. Fucoidan did not change prothrombin time or activated partial thromboplastin time, indicating an inability to change blood clotting. This study demonstrated that fucoidan is not toxic under this administration paradigm.

WITHDRAWN: Pycnogenol, a procyanidin-enriched extract of Pinus maritime bark, enhances glucose uptake in 3T3-L1 adipocytes by activated GLUT4.

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