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Any microorganisms killing molecules have some cytotoxicity more or less. The effective way of reducing cytotoxicity mainly included two approaches: One was reducing the concentration of antiseptic, while this would lead to the decreased antimicrobial efficiency; the other way was choosing suitable antiseptics and then combining of them, which can balance the disinfection and cytotoxicity. In this paper, hydroxypropyltrimethyl ammonium chloride chitosan (HACC), a cationic natural macromolecular, as the first antiseptic, incorporated with polyhexamethylene biguanide (PHMB), a smaller molecular weight cationic antiseptic polymer, as the second antiseptic, their disinfection effect and cell cytotoxicity in borate buffer solution were investigated at fairly low contents. When HACC/PHMB weight ratios were 100/1 and 150/1, the disinfection solutions produced >1-log reductions against C. albicans and >3-log reductions against S. aureus and P. aeruginosa. HACC/PHMB disinfection solution at weight ratio of 150/1 even showed a highest antimicrobial efficiency and the cell proliferation rates were approximately 100% in MTT assays. Meanwhile, the research of micromorphology and fluorescence spectra indicated that bigger aggregation state of HACC-PHMB were helpful to improve antimicrobial ability. These results showed that the HACC-PHMB combination might be a promising candidate for novel antimicrobial group for biomedical applications. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is an opportunistic pathogen causing severe respiratory infections. Acylated homoserine lactones (AHLs) are self-generated diffusible signal molecules that mediate population density dependent gene expression (quorum sensing, QS) in a variety of Gram-negative bacteria, and several virulence genes of bacterial pathogens are known to be controlled by QS. Hence, fitness mutant of virulent factors is beneficial for natural selection. In this study, strains of P. aeruginosa isolated from chronic lung infection of cystic fibrosis patients, were screened for AHLs production by using indicator strains of Chromobacterium violaceum CV026 and Agrobacterium tumefaciens strain At136. Four AHLs defective strains were selected from fifty-three clinical isolates. PCR analysis revealed that only one isolate was negative for lasR gene. These four AHLs defective isolates produced less virulence factors and forming less biofilm than PAO1. Only isolate PA41 produce little more pyocyanin than PAO1. The results indicate that, despite the pivotal role of QS in the pathogenesis of P. aeruginosa infections, AHLs-deficient strains are still capable of causing infections in human. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus causes a broad range of life-threatening diseases in humans. This bacterium produces a large number of extracellular virulence factors that are closely associated with specific diseases which are controlled by quorum sensing. In this study, we show that azithromycin was active against methicillin-resistant Staphylococcus aureus (MRSA) strains with MICs ranged from 32 to 64 μg/mL. Azithromycin at subinhibitory concentration, markedly reduced the production of α-hemolysin at (1/16MIC, 1/8MIC) and biofilm formation at (1/16MIC, 1/8MIC), respectively. The results indicated that sub-inhibitory concentrations of azithromycin decreased the production of α-hemolysin and biofilm formation in MRSA in a dose-dependent manner. Therefore, azithromycin may be useful in the treatment of α-hemolysin producing and biofilm formation MRSA infections. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa produces multiple virulence factors that have been associated with quorum sensing. The aim of this study was to evaluate the prevalence of drug resistant profiles and quorum sensing related virulence factors. Pseudomonas aeruginosa were collected from different patients hospitalized in China, the isolates were tested for their susceptibility to different common antimicrobial drugs and detected QS-related virulence factors. We identified 170 isolates displaying impaired phenotypic activity, approximately 80 % of the isolates were found to exhibit the QS-dependent phenotypes, among them, 12 isolates were defective in AHLs production, and therefore considered QS-deficient strains. Resistance was most often observed to Cefazolin (81.2 %), followed by trimethoprim-sulfamethoxazole (73.5 %), ceftriaxone (62.4 %) and Cefotaxime, Levofloxacin, Ciprofloxacin (58.8 %), and to a lesser extent Meropenem (20.0 %), Cefepime (18.8 %), and Cefoperazone/sulbactam (2.4 %) The QS-deficient isolates that were negative for virulence factor production were generally less susceptible to the antimicrobials. The results showed a high incidences of antibiotic resistance and virulence properties in P. aeruginosa, and indicate that the clinical use of QS-inhibitory drugs that appear superior to conventional antimicrobials by not exerting any selective pressure on resistant strains. [ABSTRACT FROM AUTHOR]

An HPLC method for the determination of rosmarinic and caffeic acids in several aromatic herbs, namely, rosemary, sage, thyme, spearmint, balm, and lavender, has been developed and validated. The separation system consisted of a C18 reversed-phase column, a gradient elution system of methanol/water containing orthophosphoric acid, and a photodiode array detector. The content of rosmarinic and caffeic acids was found to be 2.0–27.4, and 0–0.4 mg/g, respectively, in the aromatic herbs analysed. The described method is simple, sensitive, reproducible and ideally suited for rapid routine analysis. [Copyright &y& Elsevier]

An HPLC method for the determination of hamamelitannin, catechins and gallic acid in witch hazel bark, twig and leaf has been developed. The separation system consisted of a C18 reversed-phase column, a gradient elution system of methanol/water and orthophosphoric acid, and a photodiode array detector. The concentrations of hamamelitannin, gallic acid, (+)-gallocatechin and (+)-catechin were 4.77, 0.59, 0.22 and 0.39% (w/w), respectively, in the bark. Hamamelitannin and catechins were also detected in the leaves at concentration less than 0.04% (w/w). This method is simple, sensitive and reproducible, ideally suited for rapid, routine analysis. [Copyright &y& Elsevier]

A simple high performance liquid chromatographic analysis of tea catechins using relative response factors has been developed. The separation system consisted of a C18 reversed-phase column, a gradient elution system of methanol/water and orthophosphoric acid, and a photodiode array detector. Relative response factors for catechins are given on different columns and relative to different references. It has been shown that the relative response factors for catechins are quite similar at 210 nm of detection under different analytical conditions (different columns, different elution systems, and different HPLC instruments). (+)-Catechin was selected as the reference compound for calculating the relative response factors of the catechins. Using this method, not every catechin is needed as a reference standard, making the method ideal for rapid, routine analysis, especially for those laboratories where catechin standards are not readily available. The method is applicable to all kinds of tea, tea extracts and some tea containing products. It is especially useful for the determination of (+)-gallocatechin and (+)-catechin, which often are regarded as being present below detectable limits when detected at 280 nm, and (−)-catechin gallate, which takes a long time to elute in isocratic systems. [Copyright &y& Elsevier]

Bronopol (2-bromo-2-nitropropane-1,3-diol) is widely used as an anti-microbial in cosmetics, external medicaments, shampoos and bath preparations. A reversed-phase high performance liquid chromatographic separation method with UV spectrophotometric detection was developed for the determination of bronopol and its degradation products. Degradation of bronopol was observed in aqueous medium, giving rise to non-reproducible data. To overcome this problem, HPLC grade methanol (water content <0.05%) was used for sample preparation. In addition, the parameters for the HPLC analysis of bronopol were optimised. It was found that bronopol standards and product samples were stable in methanol for at least 1 month at ambient temperature, thus allowing a quantitative and reproducible determination of bronopol. [Copyright &y& Elsevier]

Bailemian (BLM) is reportedly used for the treatment of insomnia as a traditional Chinese medicine in China for many years. However, the anti-insomnia mechanisms of BLM are still unknown. The present study aims to investigate the anti-insomnia activity of BLM by evaluating its influence on the relevant neurotransmitters and gut microbiota in p -chlorophenylalanine (PCPA) induced insomnia mice. The results indicated that the level of GABA, 5-HT, DA, and NE is significantly decreased in the PCPA-induced insomnia model group compared with the control group, while the level of Glu is higher than the control group. Treatment with BLM could ameliorate the symptoms of insomnia and significantly modulate the levels of the neurotransmitters mentioned above in brain and colonic faeces. Furthermore, the structure and composition of gut microbiota were changed after the administration of BLM and can increase the percentage of beneficial bacterial species in gut microbiota. These results indicated that Bailemian could ameliorate the symptoms of insomnia, and its effects may be through modification of the neurotransmitters levels and gut microbiota composition. Image 1 • The administration of Bailemian can alleviate PCPA-induced insomnia in mice. • Bailemian regulated the level of neurotransmitters in the brain and colonic faeces. • Bailemian could modulate the composition and enriched the beneficial species of gut microbiota. • Bailemian alleviated p -chlorophenylalanine-induced insomnia, maybe through the brain-gut axis. [ABSTRACT FROM AUTHOR]

Quaternized chitosan is a cationic biopolymer with good antibacterial activity, biocompatibility, and biodegradability, and it has been widely applied in many fields. We have developed a convenient method to evaluate the antibacterial activity of hydroxypropyltrimethylammonium chloride chitosan (HACC) with a nonionic surfactant poloxamer in aqueous solution by monitoring the change of the oxidation peak current in cyclic voltammetry. Increasing values of the oxidation peak current were positively correlated with the antibacterial activity of HACC-poloxamer solutions. Optical microscope images, the zeta potential, and fluorescence spectroscopy showed that the aggregation state of HACC-poloxamer was related to the ratio of the two polymers and also to the antibacterial activity and oxidation peak current. At an HACC-to-poloxamer ratio of 1:0.75, the maximum surface charge density and the smooth edge of HACC-poloxamer aggregates can accelerate diffusion in aqueous solution. It is expected that this convenient method can be applied for a quick evaluation of the antibacterial activity of cationic biopolymers in aqueous solution. [ABSTRACT FROM AUTHOR]

Presents information on a study which described a clear observation of ferroelectric microdomains induced by laser damage. Discussion on the mechanism of the microdomains appearing in laser-damaged motion; Microscopic distribution of density; Paraelectric structure of lithium niobium oxygen[sub3] crystal.

Ankylosing spondylitis (AS) is a chronic inflammatory disease characterized by sacroiliac joint lesions and spinal ascending involvement. The aim of this work was at investigating the gut microbiota profile and proinflammatory cytokines in AS patients. Gut microbiota of AS patients was clearly different from that of healthy human controls. 16S rRNA sequencing analysis demonstrated a changed microbial diversity in the AS patients, and there was a significant increase in the abundance of Cyanobacteria, Deinococcota, Patescibacteria, Actinobacteriota, and Synergistota at a phyla level increased in AS, while the relative abundance of Acidobacteriota, Bdellovibrionota, Campylobacterota, Chloroflexi, Gemmatimonadota, Myxococcota, Nitrospirota, Proteobacteria, and Verrucomicrobiota declined in AS patients. ELISA results for the markers of inflammation in the AS patients revealed increased concentrations of proinflammatory cytokines such as IL-23, IL-17, and IFN-γ. Our findings support the fact that the intestinal microbiota are altered in AS with an inflammatory status, which indicates that gut microbiota should be a potential target for ankylosing spondylitis therapy. [ABSTRACT FROM AUTHOR]

Hsa-miR-196a-5p is involved in tumorigenesis and progression. However, the driving factors for hsa-miR-196a-5p overexpression and its correlation with the clinicopathological features and prognosis of patients remain unclear in glioma. Thus, this study aimed to investigate the prognostic value of hsa-miR-196a-5p and its correlation with MIR196A2 methylation in glioma. We observed that hsa-miR-196a-5p expression was upregulated in glioma. Next, 112 patients were divided into high (n = 56) and low (n = 56) hsa-miR-196a-5p expression groups. The chi-square test showed that hsa-miR-196a-5p expression was significantly related to age, WHO grade, histopathology, IDH mutation status, and 1p/19q codeletion. Univariate and multivariate Cox regression analyses showed that hsa-miR-196a-5p expression was an independent prognostic factor. GO and KEGG enrichment analyses showed that hsa-miR-196a-5p may be involved in the MAPK signaling, focal adhesion and cancer-related pathways. Compared with the normal astrocyte cell line, glioma cell lines had an unregulated MIR196A2 methylation level, which was confirmed by TCGA data. The hypermethylated CpG sites of MIR196A2 were mainly concentrated in the gene body region, which was significantly associated with hsa-miR-196a-5p overexpression. Kaplan-Meier curves revealed that MIR196A2 hypermethylation was a poor prognostic factor. These findings suggest that hsa-miR-196a-5p overexpression may be involved in malignant biological behaviors, and MIR196A2 hypermethylation of the gene body was significantly associated with hsa-miR-196a-5p overexpression, which was a poor prognostic factor of glioma. Therefore, MIR196A2 hypermethylation may act as an early marker of prognosis of patients with glioma. • Hsa-miR-196a-5p overexpression was associated with clinical malignant biological behavior of glioma. • Hsa-miR-196a-5p expression may be an independent prognostic risk factor for glioma patients. • The MIR196A2 hypermethylation of gene body was significantly associated with hsa-miR-196a-5p overexpression. [ABSTRACT FROM AUTHOR]

Background: Although aberrant expression of N6‐methyladenine (m6A) methylation‐related genes contribute to tumorigenesis in many solid tumors, the prognostic value of the m6A‐related genes and their correlation with clinicopathological features in gliomas need advanced study. Methods: The clinical and sequencing data of 288 patients with glioma were extracted from Chinese Glioma Genome Atlas database. By univariate and multivariable Cox regression analysis, the m6A‐related prognostic genes were identified, and their correlation with clinicopathological features was further analysis. A nomogram was constructed by R software and the performance of it was assessed by calibration and time‐dependent receiver operating characteristic curve. Results: Nine m6A‐related genes were identified as independent prognostic factors, which were mostly enriched in RNA splicing, regulation of immune response and vesicle‐mediated transport. By expression value and regression coefficient of these genes, we constructed risk score of each patient, which was highly associated with clinicopathological features. Kaplan–Meier curve showed that the prognosis of patients with high‐risk scores was significantly worse than that with low‐risk scores (HR = 4.30, 95% CI = 3.16–5.85, p < 0.0001). A nomogram was constructed based on the nine m6A‐related genes signature and clinicopathological features with well‐fitted calibration curves (c‐index = 0.82), showing high specificity and sensitivity (area under the curve for 1‐, 3‐, and 5‐years survival probability = 0.874, 0.918, and 0.934). Conclusions: A nine m6A‐related genes signature was identified in gliomas. The m6A‐related risk score is a novel prognostic factor for patients with glioma, and is associated with clinicopathological features. Moreover, the nomogram based on the nine m6A‐related genes signature and clinicopathological features had good efficacy in predicting the survival probability. [ABSTRACT FROM AUTHOR]

Green tea, a water extract of non-fermented leaves of Camellia sinensis L., is one of the nonalcoholic beverages in China. It is becoming increasingly popular worldwide, because of its refreshing, mild stimulant and medicinal properties. Here we examined the quorum sensing inhibitory potentials of tea polyphenols (TP) as antivirulence compounds both in vitro and in vivo. Biosensor assay data suggested minimum inhibitory concentrations (MICs) of TP against selected pathogens were 6.25 ~ 12.5 mg/mL. At sub-MIC, TP can specifically inhibit the production of violacein in Chromobacterium violaceum 12472 with almost 98% reduction at 3.125 mg/mL without affecting its growth rate. Moreover, TP exhibited inhibitory effects on virulence phenotypes regulated by QS in Pseudomonas aeruginosa. The total proteolytic activity, elastase, swarming motility and biofilm formation were reduced in a concentration-dependent manner. In vivo, TP treatment resulted in the reduction of P. aeruginosa pathogenicity in Caenorhabditis elegans. When its concentration was 3.125 mg/mL, the survival rate reached 63.3%. In the excision wound infection model, the wound contraction percentage in treatment groups was relatively increased and the colony-forming units (CFU) in the wound area were significantly decreased. These results suggested that TP could be developed as a novel non-antibiotic QS inhibitor without killing the bacteria but as an antivirulence compound to control bacterial infection. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the regulatory effect and mechanism of microRNA (miR)-185 in diabetic angiopathy. The expression of miR-185 and nitric oxide synthase 2 (NOS2) in the blood from diabetic patients was examined by reverse transcription-quantitative PCR and enzyme-linked immunosorbent assay. After establishment of diabetic rats, the expression of miR-185 and NOS2 in vascular tissues and blood was also measured. Then, miR-185 was overexpressed in HMEC-1 cells and the expression of NOS2 was determined. Dual-luciferase reporter assay was used to identify the direct interaction between miR-185 and NOS2 mRNA. The expression of NOS2 was upregulated and the expression of miR-185 was downregulated in the blood from patients with diabetes. Vascular tissues and blood of diabetic rats showed similar trends compared with that of human. HMEC-1 cells with overexpression of miR-185 had decreased expression of NOS2. Dual-luciferase reporter assay demonstrated the direct binding between miR-185 and NOS2. The present study demonstrates that upregulation of NOS2 in diabetic patients is associated with the downregulation of miR-185, which participates in the progression of diabetes possibly through regulating NOS2 expression. [ABSTRACT FROM AUTHOR]

Melastoma dodecandrum Lour. (MDL) is component used in traditional Chinese medicine that is widely distributed throughout southern China. MDL has been long utilized in clinical treatment for various conditions, such as inflammation. However, the toxicity and underlying anti-inflammatory mechanism of MDL remain to be elucidated. In the present study, Sprague-Dawley rats received intragastric administration of MDL for 2 months, and the toxicity of MDL was investigated. The rats were treated with lipopolysaccharide (LPS) for 8 h to determine the potential anti-inflammatory mechanism of MDL. The results demonstrated that MDL alone did not affect the expression levels of factors associated with inflammation (IL-1β, IL-6 and TNF-α) and oxidative stress [malondialdehyde (MDA), superoxide dismutase (SOD) and nitric oxide (NO)] in the rat serum and exerted no effects on rat liver and kidneys. By contrast, MDL attenuated LPS-induced inflammation and oxidative stress by regulating specific cytokines, such as IL-1β, IL-6, TNF-α, MDA, SOD and NO in the rat serum and alleviated LPS-induced liver and kidney damage. Additionally, compared with the LPS group, MDL inhibited CD4+ T cell differentiation into Th1 and Th17 cells and enhanced CD4+ T cell differentiation into Th2 and Treg cells. MDL also suppressed reactive oxygen species (ROS) production and mitochondrial apoptosis by modulating mitochondrial apoptosis-related proteins in spleen CD4+ T cells. In conclusion, the results of the present study demonstrated the non-toxic nature of MDL and revealed that it alleviated LPS-induced inflammation and oxidative stress by regulating differentiation and ROS production in CD4+ T cells. [ABSTRACT FROM AUTHOR]

Deals with a study which investigated the high-pressure Raman spectra of lithium niobate crystal. Background on the crystal; Presentation of the results; Details on the room temperature structure of lithium niobate.