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The caries-preventive effect of topical fluoride application has been corroborated by a number of clinical studies. However, the effect of fluoride on oral microecology remains unclear. To monitor the effect of fluoride on dental plaque microecology and demineralization/remineralization balance of enamel initial caries. Three-year-old children were enrolled and treated with fluoride at baseline and 6 months. International Caries Detection and Assessment System II indices of 52 subjects were measured at baseline, 3, 6, and 12 months. Supragingival plaque samples of 12 subjects were collected at baseline, 3 and 14 days for 16S rRNA sequencing. Changes in microbial community structure were observed at 3 days after fluoridation. Significant changes in the relative abundance of microorganisms were observed after fluoride application, especially Capnocytophaga, unidentified Prevotellaceae and Rothia. Functional prediction revealed that cell movement, carbohydrate and energy metabolism were affected significantly after fluoride application. Fluoride significantly inhibited enamel demineralization and promoted remineralization of early demineralized caries enamel at 3 months. Fluoride application significantly inhibited the progression of enamel initial caries and reversed the demineralization process, possibly by disturbing dental plaque microecology and modulating the physicochemical action of demineralization/remineralization. This deepened our understanding of caries-preventive effects and mechanisms of fluoride. [ABSTRACT FROM AUTHOR]

The stability of polarization vortex is absolutely crucial to the service performance of promising ferroelectric storage devices. Some phase field simulations were conducted on the PbTiO3 nanosheets with an initial polarization vortex under uniaxial tension or compression to investigate the conditions and types of vortex instability as well as the effects of the nanosheet size and temperature on them. The instability of polarization vortex has strong size and temperature dependence. The critical tensile stress decreases with increasing nanosheet size, and only the α-type vortex instability is observed in tensile nanosheets. However, the critical compressive stress first increases and then decreases with increasing nanosheet size, and there exists a peak size. The β-type (including β1 and β2-type) instability occurs when the nanosheet size is less than the peak size, but the α-type instability occurs when the nanosheet size is larger than the peak size. An elevated temperature reduces the critical tensile and compressive stresses, but increases the peak size. These are very important for design of promising nano-ferroelectric devices as high density memories. [ABSTRACT FROM AUTHOR]

Antihypertensive medications may have some impacts on cancer. The influence of antihypertensive medications, including angiotensin converting enzyme inhibitors (ACEIs)/angiotensin II receptor blockers (ARBs), beta-blockers, calcium channel blockers (CCBs) and diuretics, on patients with pancreatic cancer (PC) remains controversial. This meta-analysis was conducted to investigate whether antihypertensive medications had a negative effect on the prognosis of patients with PC. The PubMed, Embase, Web of Science and the Cochrane Library databases were searched up to 30 November 2021. The Newcastle-Ottawa scale was used to evaluate the quality of each study. This meta-analysis was registered with PROSPERO (CRD42021279169) and was carried out by using RevMan 5.3. Twelve studies with 120,549 patients were included in this study. ACEIs/ARBs [HR = 0.89, 95% CI (0.70–1.14)], CCB (HR = 0.69, 95% CI (0.47–0.99)], beta-blockers [HR = 0.95, 95% CI (0.84–1.07)] and diuretics [HR = 1.08, 95% CI (0.91–1.29)] use had no effects on overall survival among patients with PC (all P ≥ 0.05). Antihypertensive medication will not have a negative effect on overall survival in patients with PC. PC patients with hypertension should continue to use antihypertensive medications to reduce the morbidity and mortality of cardiovascular events. [ABSTRACT FROM AUTHOR]

Polarisation vortex structures in ferroelectric materials are being considered as a promising alternative to current memory cells due to the merit of high storage density. However, ferroelectric storage devices would inevitably be affected by external loads. When an applied mechanical or electrical load reaches its critical value, it could cause the loss of stored data because the polarisation vortex loses the stability. Some phase field simulations were conducted to investigate the stability of the polarisation vortex under different stresses or curled electric fields. The results show that the polarisation vortex structure has the strongest resistance to a tensile stress, followed by a compressive stress, but the weakest to a curled electric field. The temperature sensitivity of the polarisation vortex structure to resist different loads is also significantly different. The temperature sensitivity is the strongest for the curled electric field, followed by for the tensile stress, but the weakest for the compressive stress. This work would be helpful for tuning polarisation vortex and designing ferroelectric storage devices in specific working environments. [ABSTRACT FROM AUTHOR]

As a class of typical topological structures, polarisation vortexes were characterised by the intensity vector which is defined as the curl of the polarisation at their cores. Some phase field simulations were conducted on the lead titanate nanofilms to evaluate the effects of model size, temperature, traction, and curled electric field on the formation and evolution of polarisation vortex intensity quantitatively. The results showed that increasing size, lowered temperature and increasing traction could enhance the polarisation vortex intensity, curled electric field could change the vortex rotation direction, and compressive or tensile traction could change the vortex shape. Therefore, the polarisation vortex could be tuned by the given conditions of model size, temperature, traction, and curled electric field. This is helpful to improve the understanding and control of polarisation vortex structure. [ABSTRACT FROM AUTHOR]

Central nervous system (CNS) inflammation and autophagy dysfunction are known to be involved in the pathology of neurodegenerative diseases. Manganese (Mn), a neurotoxic metal, has the potential to induce microglia-mediated neuroinflammation as well as autophagy dysfunction. NLRP3 (NLR family, pyrin domain containing 3)- CASP1 (caspase 1) inflammasome-mediated neuroinflammation in microglia has specific relevance to neurological diseases. However, the mechanism driving these phenomena remains poorly understood. We demonstrate that Mn activates the NLRP3-CASP1 inflammasome pathway in the hippocampus of mice and BV2 cells by triggering autophagy-lysosomal dysfunction. The autophagy-lysosomal dysfunction is induced by lysosomal damage caused by excessive Mn accumulation, damaging the structure and normal function of these organelles. Additionally, we show that the release of lysosomal CTSB (cathepsin B) plays an important role in Mn-induced NLRP3-CASP1 inflammasome activation, and that the increased autophagosomes in the cytoplasm are not the main cause of NLRP3-CASP1 inflammasome activation. The accumulation of proinflammatory cytokines, such as IL1B (interleukin 1 β) and IL18 (interleukin 18), as well as the dysfunctional autophagy pathway may damage hippocampal neuronal cells, thus leading to hippocampal-dependent impairment in learning and memory, which is associated with the pathogenesis of Alzheimer disease (AD). [ABSTRACT FROM PUBLISHER]