Effects of air pollutants exposure on frailty risk: A systematic review and meta-analysis.

Air pollutants have been investigated to be associated with many health issues. Recently, increasing epidemiological studies have suggested the association between air pollution exposure and risk of frailty with inconsistent findings. This systematic review and meta-analysis was to summarize and evaluate effects of exposure to various air pollutants on risk of frailty. PubMed, Embase, Scopus and Web of Science were systematically searched for relevant studies published before May 11, 2024. Studies that explored the potential relationship between exposure to air pollutants (PM2.5, PM10, O3, NOx, solid fuel, secondhand tobacco, and air quality) and risk of frailty were included. The quality of cross-sectional and cohort studies was evaluated using an eight-item assessment instrument for epidemiological studies and Newcastle-Ottawa Scale, respectively. A total of 9,929 papers were retrieved, of which 20 met the inclusion criteria. Meta-analysis indicated that PM2.5 exposure was significantly associated with frailty assessed by the frailty index [OR (95% CI): 1.24 (1,11-1.38) per 10 µg/m3 increment]. Moreover, solid fuel exposures were significantly associated with an increased risk of frailty assessed by the frailty phenotype [OR (95% CI): 1.91 (1.09-3.34)] or the frailty index [OR (95% CI): 1.25 (1.11-1.41)]. Exposure to PM2.5 and solid fuel increases the risk of frailty. Environmental protection policies and public health measures should be developed to reduce PM2.5 concentrations. Effective measures, such as improving stoves and using clean fuels, should be taken to reduce indoor air pollution levels.

Copy number deletion of PLA2G4A affects the susceptibility and clinical phenotypes of schizophrenia.

Phospholipase A2(PLA2) superfamily is recognized as being involved in the pathogenesis of schizophrenia by affecting lipid homeostasis in cell membranes. We hypothesized that PLA2 gene copy number variation (CNV) may affect PLA2 enzyme expression and be associated with schizophrenia risk. This study indicated that in the discovery stage, an increased copy number of PLA2G6 and the deletion of PLA2G3, PLA2G4A, PLA2G4F and PLA2G12F was associated with increased risk of schizophrenia. CNV segments involving six PLA2 genes were detected in publicly available datasets, including two deletion segments specific to the PLA2G4A gene. The relationship between the deletion of PLA2G4A and susceptibility to schizophrenia was then reaffirmed in the validation group of 806 individuals. There was a significant correlation between PLA2G4A deletion and the symptoms of poverty of thought in male patients and erotomanic delusion in females. Furthermore, ELISA results demonstrate a significant decrease in peripheral blood cytosolic PLA2(cPLA2) levels in patients with the PLA2G4A deletion genotype compared to those with normal and copy number duplicate genotypes. These data suggest that the functional copy number deletion in the PLA2G4A gene is associated with the risk of schizophrenia and clinical phenotypes by reducing the expression of cPLA2, which may be an indicator of susceptibility to schizophrenia.

Correlation between in vitro starch digestibility and starch structure/physicochemical properties in rice.

Natural resistant starch (RS) in rice provides human health benefits, and its concentration in rice is influenced by the structure and physicochemical properties of starch. The native starch structures and physicochemical properties of three rice varieties, QR, BR58, and BR50, and their relationships to in vitro digestibility were studied. The starch granules in all three varieties were irregular or polyhedral in shape. There were a few oval granules and a few pinhole structures in QR, no oval granules but a higher number of pinholes in BR58, and no oval granules and pinholes in BR50. QR is a low-amylose (13.8 %), low-RS (0.2 %) variety. BR58 is a low-amylose (15.3 %), high-RS (6.5 %) variety. BR50 is a high-amylose (26.7 %), high-RS (8.3 %) variety. All three starches exhibited typical A-type diffraction patterns. Starch molecular weight, chain length distribution, starch branching degree, pasting capabilities, and thermal properties differed considerably between the rice starches. The RS contents of the rice starch varieties were positively correlated with AAC, Mw/Mn, Mz/Mn, peak 3, B, PTime, and Tp and negatively correlated with Mn, peak 2, DB, PV, and BD, according to Pearson's correlation analysis. These findings may be helpful for the breeding and development of high-RS rice varieties.

Dosage Effect of Wet-Process Tuff Silt Powder as an Alternative Material of Sand on the Performance of Reactive Powder Concrete.

A large amount of stone powder is produced during the production of machine-made sand. This research aims to study the effect of wet-process tuff silt powder (WTSP) dosages (as an alternative sand material to utilize waste stone powder and reduce environmental hazards) on reactive powder concrete's (RPC) mechanical performance. The physical and chemical properties of WTSP were analyzed as per relevant standards. This study prepared RPC samples with various WTSP content (0%, 6%, 12%, and 18%) to replace quartz sand at the same water-binder ratio (0.14) and allowed the samples to cure for 3 days, 7 days and 28 days prior to unconfined compression testing and flexural testing. Scanning electron microscopy (SEM) and Mercury Intrusion Porosimetry (MIP) testing were also carried out to observe the evolution of macroscopic properties in response to replacing part of quartz sand with the same amount of WTSP. The results show that the developed flexural and unconfined compressive strength (UCS) decreases slowly with a greater dosage of WTSP. However, when the WTSP content is 12% or less, the RPC made with WTSP satisfies the industrial application threshold regarding mechanical properties. For RPC samples containing more than 12% WTSP, the UCS and flexural strength showed a dramatic drop. Thus 12% of WTSP content was deemed the maximum and the corresponding UCS of 104.6 MPa and flexural strength of 12 MPa for 28 days of curing were the optimums. The microscopic characteristics indicate that the addition of WTSP can effectively fill the large pores in the RPC micro-structure, hence reducing the porosity of RPC. Furthermore, the WTSP can react with the cementitious material to form calcium aluminate during the hydration process, further strengthening the interface. The alkaline calcium carbonate in WTSP could improve the interfacial adhesion and make the structure stronger.