The effect of metformin on senescence of T lymphocytes.

BACKGROUND: Immunosenescence occurs as people age, leading to an increased incidence of age-related diseases. The number of senescent T cells also rises with age. T cell senescence and immune response dysfunction can result in a decline in immune function, especially in anti-tumor immune responses. Metformin has been shown to have various beneficial effects on health, such as lowering blood sugar levels, reducing the risk of cancer development, and slowing down the aging process. However, the immunomodulatory effects of metformin on senescent T cells still need to be investigated. METHODS: PBMCs isolation from different age population (n = 88); Flow Cytometry is applied to determine the phenotypic characterization of senescent T lymphocytes; intracellular staining is applied to determine the function of senescent T cells; Enzyme-Linked Immunosorbent Assay (ELISA) is employed to test the telomerase concentration. The RNA-seq analysis of gene expression associated with T cell senescence. RESULTS: The middle-aged group had the highest proportion of senescent T cells. We found that metformin could decrease the number of CD8 + senescent T cells. Metformin affects the secretion of SASP, inhibiting the secretion of IFN-γ in CD8 + senescent T cells. Furthermore, metformin treatment restrained the production of the proinflammatory cytokine IL-6 in lymphocytes. Metformin had minimal effects on Granzyme B secretion in senescent T cells, but it promoted the production of TNF-α in senescent T cells. Additionally, metformin increased the concentration of telomerase and the frequency of undifferentiated T cells. The results of RNA-seq showed that metformin promoted the expression of genes related to stemness and telomerase activity, while inhibiting the expression of DNA damage-associated genes. CONCLUSION: Our findings reveal that metformin could inhibit T cell senescence in terms of cell number, effector function, telomerase content and gene expression in middle-aged individuals, which may serve as a promising approach for preventing age-related diseases in this population.

Synthesis of metalla-dual-azulenes with fluoride ion recognition properties.

Azulene-based conjugated systems are of great interests due to their unusual structures and photophysical properties. Incorporation of a transition metal into azulene skeleton presents an intriguing opportunity to combine the dπ-pπ and pπ-pπ conjugated properties. No such metallaazulene skeleton however has been reported to date. Here, we describe our development of an efficient [5 + 2] annulation reaction to rapid construction of a unique metal-containing [5-5-7] scaffold, termed metalla-dual-azulene (MDA), which includes a metallaazulene and a metal-free organic azulene intertwined by sharing the tropylium motif. The two azulene motifs in MDA exhibit distinct reactivities. The azulene motif readily undergoes nucleophilic addition, leading to N-, O- and S-substituted cycloheptanetrienyl species. Demetalation of the metallaazulene moiety occurs when it reacts with nBu4NF, which enables highly selective recognition of fluoride anion and a noticeable color change. The practical [5 + 2] annulation methodology, facile functional-group modification, high and selective fluoride detection make this new π-conjugated polycyclic system very suitable for potential applications in photoelectric and sensing materials.

Efficacy of air purifier therapy for patients with allergic asthma

Objectives: This study aimed to evaluate the efficacy of air purifier therapy for patients with allergic asthma. Methods: Thirty-eight subjects were categorized under two groups namely treatment group and control group. All subjects were under 18 years of age and they had been clinically diagnosed with allergic asthma. The treatment group used high efficiency particulate air (HEPA) purifiers for six consecutive months, and the control group did not use the air filters. Particulate matter (PM) data and dust samples (from bedding and a static point) were collected from the subjects’ bedrooms before they started using the air purifiers and each month thereafter. Simultaneously, the subjects were asked to complete a questionnaire for the Asthma Control Test (ACT) or Childhood Asthma Control Test (C-ACT). Fractional exhaled nitric oxide (FENO) tests were performed at the start and end of the study. The concentrations of Der p1 and Der f1 were measured in the dust samples. Results: (1) After utilizing the air purifier, the concentrations of house dust mite (HDM) allergens (Der p1+ Der f1) in the dust samples decreased. In addition, the PMindoor/outdoor values significantly decreased. (2) The ACT and C-ACT scores in the treatment group maintained a steady significant upward trend. (3) At the end of the study, the FENO levels in both groups were lower, although the differences were not significant. Conclusions: It is witnessed that HEPA air purifiers can decrease indoor HDM allergen and PM levels and improve the quality of life for allergic asthma patients (AU)

[Preparation of Ag3PO4/g-C3N4 Composite Photocatalysts and Their Visible Light Photocatalytic Performance].

The visible light-driven photocatalyst Ag3PO4/g-C3N4 was synthesized by a simple in-situ precipitation method. The synthesized samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, and UV-vis diffuse reflectance spectroscopy. Compared with that of single Ag3PO4 and g-C3N4, the Ag3PO4/g-C3N4 composite had a higher catalytic efficiency for levofloxacin. According to the energy band analysis and free radical capture experiment, the mechanism of the Z-type heterostructure of the Ag3PO4/g-C3N4 composite was proposed.

Preoperative and postoperative medical therapies for chronic rhinosinusitis: National surveys among Chinese otolaryngologists.

OBJECTIVE: The aim of this study was to evaluate clinical practice patterns of preoperative and postoperative medical therapies immediately surrounding sinus surgery for chronic rhinosinusitis (CRS) by Chinese otolaryngologists. METHODS: Two anonymous web-based surveys of preoperative and postoperative medical therapies were performed. These surveys assessed the frequency of prescription of oral corticosteroids, intranasal corticosteroid sprays, oral antibiotics, nasal saline irrigation, oral antihistamines, nasal antihistamines, anti-leukotriene agents, topical decongestants and oral mucolytics. RESULTS: A total of 304 (17.5%) preoperative and 143 (23.5%) postoperative questionnaires were completed and returned. Seventy-eight percent, 63% and 56% of respondents used preoperative intranasal corticosteroid sprays, oral antibiotics and oral mucolytics "always or often", respectively. Ninety-four percent, 93%, 72% and 69% of respondents used postoperative intranasal corticosteroid sprays, nasal saline irrigation, oral antibiotics and oral mucolytics "always or often", respectively. Oral antihistamines, nasal antihistamines, anti-leukotrienes and topical decongestants were not commonly used preoperatively or postoperatively. CONCLUSIONS: Our study demonstrated that current practice patterns of preoperative medical therapies among otolaryngologists are not uniformly based on evidence-based outcomes research. Postoperative oral antibiotics, intranasal corticosteroid sprays, nasal saline irrigation and oral mucolytics are commonly used by a majority of Chinese otolaryngologist for CRS. Practice patterns of postoperative medical therapy reflect recent guidelines.

[Removal of Humic Acid from Water by Magnetic Chitosan-Grafted Polyacrylamide].

For high-efficiency removal of humic acid (HA), a natural organic matter in the water source, an adsorbent named magnetically modified chitosan-grafted polyacrylamide (MC-g-PAM) was developed by using an in situ coprecipitation method. Analytical instruments, such as a Fourier transform infrared (FTIR) spectroscope, scanning electron microscope (SEM), vibrating sample magnetometer (VSM), and specific surface area tester (BET), were used to characterize and analyze this material. With the aid of batch tests, the removal efficiency and mechanism of humic acid in water samples were investigated. The results show that the specific surface area and specific saturation magnetization values of the prepared MC-g-PAM are 27.065 m2·g-1 and 9.63 emu·g-1, respectively. The adsorption of humic acid by MC-g-PAM is an endothermic process and the Langmuir isotherm model and the pseudo-second-order kinetic equation fit the adsorption process well. At 25℃, the equilibrium adsorption capacity of MC-g-PAM to humic acid reaches 120.77 mg·g-1.

Mechanism of pretreatment using magnetic poly(glycidyl methacrylate) resin in an ultrafiltration membrane system used in algae-rich water treatment.

Ultrafiltration (UF) membrane fouling brought by algae-rich water controlling has been the research focus in recent years. The pretreatment of magnetic poly(glycidyl methacrylate) (m-PGMA) for sedimental tank effluent was investigated as well as its performance in combined UF processes. The optimal dose of m-PGMA was found to be 5 mL/L, which can bring a significant improvement to the removal efficiency of natural organic matter. With regards to membrane fouling, the use of m-PGMA also resulted in lowered irreversible and reversible membrane resistances in comparison with results obtained when operating without m-PGMA. In addition, four classic filtration models were introduced to analyse the fouling mechanisms. The proportion of standard blocking of pores has been weakened in the mechanism of membrane fouling when the pretreatment of m-PGMA exists. A very loose cake layer and relieved pore blockage were observed by scanning electron microscopy during m-PGMA/UF process.

Poly[diaqua-bis(µ(2)-5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ato-κN,O:O)lead(II)].

In the title complex, [Pb(C(8)H(9)N(2)O(4))(2)(H(2)O)(2)](n), the eight-coordinate Pb(II) atom lies on a twofold rotation axis and adopts a slightly distorted square-anti-prismatic N(2)O(6) coordination geometry. The ligand donor atoms are the tertiary N atoms of the imidazole rings and the carboxyl-ate O atoms of two chelating 5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ate ligands, the carb-oxy O atoms of two additional imidazole ligands and two water O atoms. The carb-oxy O and the N,O-chelate systems also link adjacent Pb(II) atoms, forming a two-dimensional layer structure, with four individual Pb(II) atoms located at the corners of a square. These layers are further inter-connected by an extensive array of O-H⋯O and N-H⋯O hydrogen bonds into a three-dimensional network.