Interaction of the gut microbiota and brain functional connectivity in late-life depression.

BACKGROUND: Increasing evidence suggests an important role of the gut microbiome in the pathogenesis of mental disorders, including depression, along the microbiota-gut-brain axis. We sought to explore the interactions between gut microbe composition and neural circuits in late-life depression (LLD). METHODS: We performed fecal 16S ribosomal RNA (rRNA) sequencing and resting-state functional magnetic resonance imaging in a case-control cohort of older adults with LLD and healthy controls to characterize the association between gut microbiota and brain functional connectivity (FC). We used the Hamilton Depression Rating Scale (HAMD) to assess depressive symptoms. RESULTS: We included 32 adults with LLD and 16 healthy controls. At the genus level, the relative abundance of Enterobacter, Akkermansiaceae, Hemophilus, Burkholderia, and Rothia was significantly higher among patients with LDD than controls. Reduced FC within mood regulation circuits was mainly found in the frontal cortex (e.g., the right superior and inferior frontal gyrus, right lateral occipital cortex, left middle frontal gyrus, and left caudate) among patients with MDD. Group-characterized gut microbes among controls and patients showed opposite correlations with seed-based FC, which may account for the aberrant emotion regulation among patients with LDD. The abundance of Enterobacter (dominant genus among patients with LLD) was positively correlated with both HAMD scores (r = 0.49, p = 0.0004) and group-characterized FC (r = -0.37, p < 0.05), while Odoribacter (dominant genus among controls) was negatively correlated with both HAMD scores (r = -0.30, p = 0.04) and group-characterized FC. LIMITATIONS: The study's cross-sectional design and small sample size limit causal inferences; larger longitudinal studies are required for detailed subgroup analyses. CONCLUSION: We identified significant correlations between LDD-characterized gut microbes and brain FC, as well as depression severity, which may contribute to the pathophysiology of depression development among patients with LLD. Specific microbes were linked to altered brain connectivity, suggesting potential targets for treating LLD.

Scoring model based on cardiac CT and clinical factors to predict early good mitral valve repair in rheumatic mitral disease.

OBJECTIVE: We aimed to evaluate the mitral valve calcification and mitral structure detected by cardiac computed tomography (cardiac CT) and establish a scoring model based on cardiac CT and clinical factors to predict early good mitral valve repair (EGMR) and guide surgical strategy in rheumatic mitral disease (RMD). MATERIALS AND METHODS: This is a retrospective bi-center cohort study. Based on cardiac CT, mitral valve calcification and mitral structure in RMD were quantified and evaluated. The primary outcome was EGMR. A logical regression algorithm was applied to the scoring model. RESULTS: A total of 579 patients were enrolled in our study from January 1, 2019, to August 31, 2022. Of these, 443 had baseline cardiac CT scans of adequate quality. The calcification quality score, calcification and thinnest part of the anterior leaflet clean zone, and papillary muscle symmetry were the independent CT factors of EGMR. Coronary artery disease and pulmonary artery pressure were the independent clinical factors of EGMR. Based on the above six factors, a scoring model was established. Sensitivity = 95% and specificity = 95% were presented with a cutoff value of 0.85 and 0.30 respectively. The area under the receiver operating characteristic of external validation set was 0.84 (95% confidence interval [CI] 0.73-0.93). CONCLUSIONS: Mitral valve repair is recommended when the scoring model value > 0.85 and mitral valve replacement is prior when the scoring model value < 0.30. This model could assist in guiding surgical strategies for RMD. CLINICAL RELEVANCE STATEMENT: The model established in this study can serve as a reference indicator for surgical repair in rheumatic mitral valve disease. KEY POINTS: • Cardiac CT can reflect the mitral structure in detail, especially for valve calcification. • A model based on cardiac CT and clinical factors for predicting early good mitral valve repair was established. • The developed model can help cardiac surgeons formulate appropriate surgical strategies.

Co-exposure to parabens, bisphenol A, and triclosan and the associations with dyslipidemia in Chinese older adults: the mediation effect of oxidative stress.

Dyslipidemia is a prevalent metabolic disorder in older adults and has negative effects on cardiovascular health. However, the combined effect of paraben, bisphenol A (BPA), and triclosan (TCS) exposure on dyslipidemia and the underlying mechanisms remain unclear. This cross-sectional study recruited 486 individuals ≥60 years in Shenzhen, China. Morning spot urine samples were collected and analyzed for four parabens, BPA, TCS, and 8-hydroxy-2'-deoxyguanosine (8-OHdG), a typical biomarker for oxidative stress, using mass spectrometry. Blood samples were tested for lipid levels using an automated biochemical analyzer. Quantile-based g-computation (QGC) was used to assess the combined effects of exposures on dyslipidemia. Mediation analysis was applied to investigate the mediating role of 8-OHdG between exposure and dyslipidemia. QGC showed that co-exposure to parabens, BPA, and TCS was positively linked with hypercholesterolemia (OR: 1.17, 95%CI: 1.10-1.24, P<0.001) and hyper-LDL-cholesterolemia (OR: 1.35, 95%CI: 1.05-1.75, P=0.019). Methylparaben (MeP), n-propyl paraben (PrP), and butylparaben (BtP) were the major contributors. 8-OHdG mediated 6.5% and 13.0% of the overall effect of the examined chemicals on hypercholesterolemia and hyper-LDL-cholesterolemia, respectively (all P<0.05). Our study indicated that co-exposure to parabens, BPA, and TCS is associated with dyslipidemia and oxidative stress partially mediate the association. Future research is needed to explore additional mechanisms underlying these relationships.

Willingness and hesitancy towards the governmental free human papillomavirus vaccination among parents of eligible adolescent girls in Shenzhen, Southern China.

BACKGROUND: Since 2020, China has actively promoted HPV vaccination for eligible adolescent girls through various pilot programmes. This study investigated parental willingness and hesitancy towards the government-sponsored, free human papillomavirus (HPV) vaccination for eligible adolescent girls in Shenzhen, Southern China. METHODS: From June to August 2022, a cross-sectional survey was conducted with parents of girls entering Grade 7, employing an adapted Vaccine Hesitancy Scale to assess vaccine hesitancy and logistic regression to identify factors influencing willingness to accept the free domestic vaccines. RESULTS: Although only 3.4% of the 2856 respondents had their daughters vaccinated against HPV prior to the survey, 91.7% were willing to utilise the governmental vaccination services. Parents with children in public schools (χ2 = 20.08, p < 0.001), those with more secure medical insurance (χ2 = 4.97, p = 0.026), and parents who had received an HPV vaccine themselves (χ2 = 28.829, p < 0.001) showed more reluctance towards the free vaccines. Vaccine hesitancy was presented in a mere 2.1% but was a significant predictor of vaccine refusal, even after adjusting for multiple factors (adjusted OR = 15.98, 95% CI: 9.06, 28.20). Notably, about four-fifths of parents of unvaccinated daughters harboured concerns about the safety and efficacy of the domestic vaccine. CONCLUSIONS: Although parents show a strong inclination to utilise the government vaccination services, their vaccine hesitancy, driven by safety concerns and a preference for imported vaccines, remains a significant barrier for rolling out vaccination coverage. This study highlights the need for multifaceted intervention strategies that address these issues to enhance HPV vaccine uptake effectively.

A quantitative proteomic study reveals oxidative stress and synapse-related proteins contributed to TDCIPP exposure induced neurotoxicity.

Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) has been consistently identified in various environmental media and biological specimens. Current understanding of the in vivo toxicities of TDCIPP is limited, especially for potential for neurotoxic and cognitive impairment effects. To better evaluate the potential adverse effect of the chemical on learning and memory, Sprague Dawley (SD) rats were administered TDCIPP via gavage at doses of 40, 120, and 360 mg/kg/day for a period of 90 days. Quantitative proteomic analysis, immunohistochemistry, and Western blotting were employed to assess alterations in proteins following exposure to TDCIPP. An open field test and the Morris Water Maze were used to assess anxiety and spatial learning memory capacity. Administration of TDCIPP induced anxiety and cognitive impairments in rats. Additionally, a noteworthy decrease in the number of neurons was observed in the hippocampal CA3 and dentate gyrus (DG) regions. Proteomic and bioinformatic analyses revealed dysregulation of numerous hippocampal proteins, particularly those associated with synapses (PKN1) or oxidative stress (GSTM4, NQO1, and BMAL1), which was further confirmed by Western blot analysis. In sum, the cognitive impairment of rats caused by TDCIPP exposure was associated with dysregulation of synaptic and oxidative stress-related proteins.

[Improving effect of selenium on spermatogenesis in mice with cyclophosphamide-induced spermatogenic impairment and its underlying mechanism].

OBJECTIVE: To investigate the effect of selenium on cyclophosphamide (CTX)-induced spermatogenic impairment (SI) in mice and its underlying mechanism. METHODS: We equally randomized 36 male KM mice into 3 SI model and 3 control groups, the first 3 treated by intraperitoneal injection of CTX at 100 mg/kg (the SI model control group), CTX plus SI model control group, selenium deficient model group (－Se SI), selenium supplemented model group (+Se SI), while latter 3 by intraperitoneal injection of normal saline (the normal control), selenium deficiency control group (－Se control), selenium addition control group (+Se control), respectively, all once a week for 6 successive weeks. Then we observed the histopathological changes in the testes of all the mice by HE staining, obtained the sperm count in the epididymides, determined the expressions of glutathione peroxidase 4 (GPx4) and SLC7A11 proteins by Western blot and ferroptosis-related genes by RT-qPCR, and examined the changes in the expressions of ferroptosis-related proteins and genes in the GC2-spd cells treated with ferroptosis inhibitors and inducers in combination with different concentrations of inorganic sodium selenite (SeS) and organic selenomethionine (SeM). RESULTS: Compared with the normal controls, the SI model mice showed significantly decreased testicular and prostatic organ coefficients, reduced spermatogenic layers, increased voids, decreased serum ferritin concentration (P<0.05), and elevated transferrin concentration (P<0.05). The organ coefficients were significantly higher in the +Se SI and +Se control than in the －Se SI and －Se control groups (P<0.05, P<0.01), with evident pathological improvement of the testis tissue in the +Se controls. The expressions of the GPx4 and solute carrier family 7 members 11（SLC7A11） genes in the testis were dramatically down-regulated in the SI model controls (P<0.01), but up-regulated in the +Se SI and +Se control compared with those in the －Se SI and －Se control group (P<0.01 and P<0.05), but there were no statistically significant differences between their protein expressions. The results of in vitro GC2 spd cell experiments indicated that the GPx4 gene and GPx4 protein levels in the - Se group were significantly lower than those in the normal control group (P<0.05), while the SLC7A11 gene level decreased (P<0.01). Different doses of SeS and SeM significantly increased the GPx4 protein expression compared to the average Se group. Low doses of SeM promoted a significant increase in GPx4 gene levels, while high doses of SeS increased the expression levels of SLC7A11 gene and SLC7A11 protein (P<0.05, P<0.01). The Se group showed a significant decrease in the levels of acsl4 and ptgs2 genes compared to the normal control group. SeM promoted the expression of acsl4, while SeS promoted the expression of ptgs2 and fth1 (P<0.01, P<0.05). The intervention results of GC2 spd showed that the Erastin group had a decrease in ptgs2 compared to the normal control group, while the SeS+Erastin and SeM+Erastin groups had an increase in ptgs2 gene expression compared to the Erastin group. However, the ptgs2 expression of Fer-1 was lower than that of the normal control group, and the ptgs2 gene level of SeS+Fer-1 and SeM+Fer-1 groups was lower than that of Fer-1 group (P<0.05); The gene quantity of GPx4 in the SeM+Erastin and SeM+Fer-1 groups increased compared to the Erastin and Fer-1 groups (P<0.01, P<0.05); SeM+Erastin and SeS+Erastin showed a decrease in SLC7A11 compared to the Erastin group, as well as SeM+Fer-1 and SeS+Fer-1 groups compared to the Fer-1 group, accompanied by an increase in acsl4 and fth1 (P<0.01). CONCLUSION: Selenium deficiency causes the reduction of the SLC7A11 and GPx4 gene levels, disorder of ferroptosis-related genes and down-regulation of the GPx4 protein expression in the mouse testis and spermatocytes. Selenium can promote the expression of GPx4, up-regulate the level of SLC7A11, and improve spermatogenesis in the testis of the mouse with SI. There are differences between organic SeM and inorganic SeS in regulating the ferroptosis pathway-related genes.

Associations between the signing status of family doctor contract services and cervical cancer screening behaviors: a cross-sectional study in Shenzhen, China.

BACKGROUND: As a core part of the primary healthcare system, family doctor contract services (FDCS) may help healthcare providers promote cervical cancer screening to the female population. However, evidence from population-based studies remains scant. This study aimed to investigate the potential associations between the signing status of FDCS and cervical cancer screening practices in Shenzhen, China. METHODS: A cross-sectional survey among female residents was conducted between July to December 2020 in Shenzhen, China. A multistage sampling method was applied to recruit women seeking health services in community health service centers. Binary logistic regression models were established to assess the associations between the signing status of FDCS and cervical cancer screening behaviors. RESULTS: Overall, 4389 women were recruited (mean age: 34.28, standard deviation: 7.61). More than half (54.3%) of the participants had signed up with family doctors. Women who had signed up for FDCS performed better in HPV-related knowledge (high-level rate: 49.0% vs. 35.6%, P<0.001), past screening participation (48.4% vs. 38.8%, P<0.001), and future screening willingness (95.9% vs. 90.8%, P<0.001) than non-signing women. Signing up with family doctors was marginally associated with past screening participation (OR: 1.13, 95%CI: 0.99-1.28), which tended to be robust among women with health insurance, being older than 25 years old at sexual debut, using condom consistently during sexual intercourse, and with a low level of HPV related knowledge. Similarly, signing up with family doctors was positively associated with future screening willingness (OR: 1.68, 95%CI: 1.29-2.20), which was more pronounced among women who got married and had health insurance. CONCLUSIONS: This study suggests that signing up with family doctors has positive associations with cervical cancer screening behaviors among Chinese women. Expanding public awareness of cervical cancer prevention and FDCS may be a feasible way to achieve the goal of cervical cancer screening coverage.

Nutrient Supplementation Improves Contact Lens-Induced Corneal Cell Damage Based on a SIRC Cellular Model.

OBJECTIVES: The long-term use of contact lenses may damage the structure of the ocular surface and cause metabolic disorders in corneal cells. Vitamins and amino acids help maintain the physiological function of the eye. In the present study, the effects of nutrient (vitamin and amino acid) supplementation on corneal cell repair after contact lens-induced damage was investigated. METHODS: High-performance liquid chromatography was used to quantify the nutrient contents of minimum essential medium, and the MTT assay was used to measure the viability of corneal cells. A Statens Seruminstitut rabbit cornea cellular model was established to simulate contact lens-induced keratopathy and investigate the effects of vitamin and amino acid supplementations on corneal cell repair. RESULTS: The high water content lens group (78%) has a cell viability as high as 83.3%, whereas the cell viability of the low water content lens group (38%) is only 51.6%. The 32.0% difference between the two groups confirms the correlation between water content of lens and corneal viability. CONCLUSIONS: Vitamin B2, vitamin B12, asparagine, and taurine supplementation may help improve contact lens-induced damage.

Human papillomavirus vaccination related knowledge, and recommendations among healthcare providers in Southern China: a cross-sectional survey.

BACKGROUND: Little research has been conducted to explore variables associated with the healthcare providers' (HCPs) understanding and recommendation of human papillomavirus vaccine (HPV) since the vaccine was approved for use in China. METHODS: A large-scale cross-sectional survey was conducted in southern China covering Guangdong, Guangxi, and Hainan provinces between April 2019 and October 2019. Firstly, descriptive analysis was used to access awareness, knowledge, barriers, and recommendations toward HPV vaccine among all participants. Multi-variable logistic regression was further applied to explore potential factors associated with awareness, acknowledgment of HPV vaccine, and recommendation behaviors toward HPV vaccine. RESULTS: 2075 questionnaires were collected, and 2054 were included in the final analysis. In total, 77.9% of participants have heard of HPV vaccine and obtained sub-optimal HPV/HPV vaccine knowledge scores with a mean (SD) of 13.8 (3.5) out of a maximum score of 23. 68.1% HCPs reported that they have recommended HPV vaccine to others. Province and profession were the most significant characteristics associated with awareness, knowledge score, and recommendation behavior toward HPV vaccine. HCPs in Guangdong obtained a much better knowledge score [Mean (SD) = 15.5 (3.0)] and reported higher recommendation behavior (82.8%). Compare with HCPs from the Division of Expanded Program on Immunization (DEPI), Community Health Center (CHC), and obstetrician-gynecologists, other non-HPV closely related professions showed a less competent knowledge of HPV and HPV vaccine [Mean (SD) = 12.5 (3.0)] and lower frequency of recommendation behavior on vaccination (58.1%). The difference in HPV vaccine knowledge among different professions was concentrating on the items about clinical pathology of HPV and the practical aspects of HPV vaccine. Educational level and title were also closely associated with their knowledge of HPV and its vaccine. Besides, knowledge scores independently determined with recommendation behavior (OR = 1.18, 95% CI 1.13-1.23). CONCLUSION: Knowledge level of HPV and HPV vaccine as well as recommendation behavior toward HPV vaccine were relatively lower in southern China and differed significantly between provinces. Profession-specific gaps on the knowledge level of HPV and HPV vaccine emphasized the need for targeted education and training to improve HCPs' engagement in the promotion of the HPV vaccine.

The effects of selenium on GPX4-mediated lipid peroxidation and apoptosis in germ cells.

Emerging evidence suggests that selenium plays an essential role in sperm maturation. However, the specific signaling pathway by which selenium exerts effect has not been elucidated. To evaluate the effect of selenium on GPX4-mediated lipid peroxidation and apoptosis in germ cells, selenium deficiency was modeled by culturing GC2-spd cells in serum-free medium. Treatment with 0.5-µM sodium selenite (NaSe) or 5.0-µM selenomethionine (SeMet) significantly improved the proliferation rate and GPX4 protein expression after selenium deficiency. Moreover, NaSe and SeMet decreased the MDA content and lipid peroxidation. When adenovirus was used to knockdown the expression of the GPX4 gene (shRNA-GPX4), the early apoptosis rate of the shRNA-GPX4 cells was significantly higher than that of the EGFP cells. Increased expression of Caspase3 and Bax, as well as MDA content were observed in the shRNA-GPX4 cells compared with EGFP cells. In further, overexpression of the GPX4 gene (ORF-GPX4) cells exhibited increased cell proliferation and decreased MDA content. However, there was no significant difference in 12/15-lox expression both in ORF-GPX4 cells and shRNA-GPX4 cells. Conclusively, GPX4 was involved in the regulation of lipid peroxidation and apoptosis in GC2-spd cells. Selenium played a role in promoting cell proliferation by mediating GPX4. The regulation of GPX4 may occur independently of 12/15-Lox. These findings confirmed the effect of selenium on spermatogenesis and offered a potential target for treating abnormal semen quality in men.

Effects of Dried Onion Powder and Quercetin on Obesity-Associated Hepatic Menifestation and Retinopathy.

Onion (Allium cepa L.), rich in flavonoids (particularly quercetin), reportedly has anti-obesity properties, but the underlying mechanisms and associated health issues remain unclear. In this study, we compared the effects of dried onion powder (DO) with that of quercetin on high-fat diet (HFD)-induced obesity, nonalcoholic fatty liver disease, and retinal neovascularization. Briefly, rats (n = 9-10 per group) were divided into control, HFD alone (43% fat), HFD + DO (1% DO), HFD + 5DO (5% DO, w/w), and HFD + quercetin (180 mg/kg). After 12 weeks, body fat, markers of metabolism, fatty liver, steatohepatitis, and retinopathy were analyzed. The results revealed that DO and 5DO dose-dependently suppressed body weight, visceral and subcutaneous fat accumulation, and epididymal adipocyte in HFD-fed rats. DO also decreased HFD-induced ALT, AST, free fatty acid, glucose, proinflammatory cytokines, and oxidative stress. DO and 5DO groups had lower triglycerides, total cholesterol, proinflammatory cytokine levels, and ACC-α (a fatty acid synthesis-associated enzyme) expression but higher hepatic antioxidant enzyme activities and fecal lipids. 5DO exhibited better or similar efficacy to quercetin. Both 5DO and quercetin increased fecal levels of acetic acid and butyric acid similarly. They also reduced lipid peroxidation of the eye, retinal adiposity, and neovascularization. However, quercetin resulted in a more apparent decrease in regulation of the Raf/MAPK pathway than DO in eye specimens. Conclusively, DO suppresses visceral, subcutaneous, and liver fat accumulation better than quercetin likely due to higher fecal fat excretion and lower oxidative stress, proinflammatory cytokine levels, and ACC-α expression. Quercetin regulating signal pathways is better than DO at reducing retinal adiposity and neovascularization.

Increased risk of short-term depressive disorder after Helicobacter pylori eradication: A population-based nested cohort study.

BACKGROUND: Depressive disorder is a major psychiatric illness, and a disturbed brain-gut-microbiome axis may contribute to its pathophysiology. Chronic Helicobacter pylori (H. pylori) infections are common in the general population and using multiple antibiotics is required for its eradication, which is associated with gut dysbiosis and may lead to depression. We aimed to evaluate the risk of psychiatrist-diagnosed depression in patients with peptic ulcer diseases (PUD) receiving anti-H. pylori therapy. MATERIALS AND METHODS: We collected data from the National Health Insurance Research Database (NHIRD) in Taiwan on PUD patients undergoing antibiotic treatment for H. pylori infection; patients and controls were matched for age, sex, income, level of urbanization, and comorbidities. RESULTS: Of the 1 million beneficiaries in the NHIRD, we identified 7087 patients for inclusion in the eradication cohort and 7087 matched non-eradication controls with PUD. Antibiotic therapy is associated with a short-term (<30 days) increase in the incidence of psychiatrist-diagnosed depressive disorder (p = 0.009, after multiple comparisons with Bonferroni correction) in the eradication cohort compared with the controls. Female (OR: 4.55, 95% CI: 1.53-13.48) PUD patients were more likely to display an increased risk of depression within 30 days after eradication therapy. Clarithromycin use was related to an elevated likelihood (OR: 3.14, 95% CI: 1.45-6.80) of subsequent depressive disorder within 30 days after eradication therapy. CONCLUSIONS: Antibiotic eradication treatment for H. pylori infection is associated with a significant short-term (less than 30 days) increase in the incidence of psychiatrist-diagnosed depressive disorder, which can be overlooked by gastroenterologists and general practitioners.

Effect of ambient temperature on stroke onset: a time-series analysis between 2003 and 2014 in Shenzhen, China.

OBJECTIVE: Evidence on the relationship between ambient temperature and morbidity of different stroke subtypes in China is limited. This study aimed to assess the influence of ambient temperature on stroke risk in Shenzhen, China. METHODS: From 1 January 2003 to 31 December 2014, 114 552 stroke cases in Shenzhen were collected. A generalised additive model with quasi-Poisson regression combined with a distributed lag non-linear model was applied to evaluate the temperature effects on stroke subtypes. Furthermore, this study explored the variability of the effects across sex, age and education. RESULTS: The immediate heat effects on ischaemic stroke (IS) and the persistent effects of ambient temperature on intracerebral haemorrhage (ICH) were significant. Overall, the cold-related relative risks (RRs) of IS, ICH and subarachnoid haemorrhage (SAH) were 1.02 (0.97-1.07), 1.16 (1.04-1.30) and 1.12 (0.61-2.04), whereas the heat-related RRs were 1.00 (0.97-1.04), 0.80 (0.73-0.88) and 1.05 (0.63-1.78), respectively. For IS, a weakly beneficial cold effect was found among men while a detrimental heat effect among both men and women, the elderly and higher-educated population at lag0. However, regarding ICH, the temperature effects in men, the young and higher-educated population are stronger at lag0-4, lag0-7 as cold reveals threat and heat reveals protection. CONCLUSION: Responses of diverse stroke subtypes to ambient temperature varied. Effective measures should be taken to increase public awareness about the effects of ambient temperature on stroke attack and to educate the public about self-protection.

Applications of Hyaluronic Acid in Ophthalmology and Contact Lenses.

Hyaluronic acid (HA) is a glycosaminoglycan that was first isolated and identified from the vitreous body of a bull's eye. HA is ubiquitous in the soft connective tissues of animals and therefore has high tissue compatibility for use in medication. Because of HA's biological safety and water retention properties, it has many ophthalmology-related applications, such as in intravitreal injection, dry eye treatment, and contact lenses. Due to its broad range of applications, the identification and quantification of HA is a critical topic. This review article discusses current methods for analyzing HA. Contact lenses have become a widely used medical device, with HA commonly used as an additive to their production material, surface coating, and multipurpose solution. HA molecules on contact lenses retain moisture and increase the wearer's comfort. HA absorbed by contact lenses can also gradually release to the anterior segment of the eyes to treat dry eye. This review discusses applications of HA in ophthalmology.

Association between short-term exposure to air pollution and ischemic stroke onset: a time-stratified case-crossover analysis using a distributed lag nonlinear model in Shenzhen, China.

BACKGROUND: Stroke, especially ischemic stroke (IS), has been a severe public health problem around the world. However, the association between air pollution and ischemic stroke remains ambiguous. METHODS: A total of 63, 997 IS cases aged 18 years or above in Shenzhen were collected from 2008 to 2014. We used the time-stratified case-crossover design combining with distributed lag nonlinear model (DLNM) to estimate the association between air pollution and IS onset. Furthermore, this study explored the variability across gender and age groups. RESULTS: The cumulative exposure-response curves were J-shaped for SO2, NO2 and PM10, and V-shaped for O3, and crossed over the relative risk (RR) of one. The 99th, 50th (median) and 1st percentiles of concentration (µg/m3) respectively were 37.86, 10.06, 3.71 for SO2, 116.26, 41.29, 18.51 for NO2, 145.94, 48.29, 16.14 for PM10, and 111.57, 49.82, 16.00 for O3. Extreme high-SO2, high-NO2, high-PM10, high-O3, and low-O3 concentration increased the risk of IS, with the maximum RR values and 95% CIs: 1.50(1.22, 1.84) (99th vs median) at 0-12 lag days, 1.37(1.13, 1.67) (99th vs median) at 0-10 lag days, 1.26(1.04, 1.53) (99th vs median) at 0-12 lag days, 1.25(1.04, 1.49) (99th vs median) at 0-14 lag days, and 1.29(1.03, 1.61) (1st vs median) at 0-14 lag days, respectively. The statistically significant minimal RR value and 95% CI was 0.79(0.66,0.94) at 0-10 lag days for extreme low-PM10. The elderly aged over 65 years were susceptible to extreme pollution conditions. Difference from the vulnerability of males to extreme high-SO2, high-NO2 and low-O3, females were vulnerable to extreme high-PM10 and high-O3. Comparing with the elderly, adults aged 18-64 year were immune to extreme low-NO2 and low-PM10. However, no association between CO and IS onset was found. CONCLUSIONS: SO2, NO2, PM10 and O3 exerted non-linear and delayed influence on IS, and such influence varied with gender and age. These findings may have significant public health implications for the prevention of IS.

Molecular Model of Dye Sensitized Titanium Oxides Based on Aryl-Amine Dye Anchored Titanium Oxo Clusters.

Model studies on dye sensitized titanium oxides have attracted wide interest with respect to their importance in understanding photoelectric and photophysical processes. Ligand modified titanium oxo clusters (TOCs) have been considered as the most appropriate models for dye sensitized solar cells (DSSCs) on the basis of their atomically precise structures. However, the ligands used previously in TOC models were seldom the dyes that really applied in DSSCs due to the difficulty with which the crystals of the dye anchored TOCs are obtained. We report herein a series of TOCs with the popularly used arylamine-cyanoacrylate dyes. As the closest model of DSSCs, the TOCs were studied by DFT calculations based on their accurate structural information. They have also been applied to photoelectric conversion evaluation by a solar cell device. Both the theoretical and application results showed that the synergistic effect of intradye molecular charge transfer (ICT) and dye to TiO cluster charge transfer (LMCT) is important in increasing the power conversion efficiency.

Water-Soluble Lanthanide-Titanium-Oxo Cluster, a Precursor for Biocompatible Nanomaterial.

Titanium-oxo clusters (TOCs) are attractive as a rapidly growing class of molecular materials due to their use as molecular models and precursors of nano-titanium-oxide. However, most TOCs can only be dissolved in nonaqueous solvents, which largely limits their potential applications in biological or environmental situations. Very few water-soluble TOCs were reported, which can be used directly in aqueous biomedical systems. However, until now, no research studies of such TOCs involved in biomedical fields have been documented. We report here a series of lanthanide-titanium-oxo clusters (LnTOCs) formulated as {H2@[Ln2Ti8(µ3-O)8(µ2-O)4(Ac)16]}3·24CH3CN·23H2O (Ln = Eu(III) 1, Tb(III) 2, and Yb(III) 3). The compounds are easily soluble in water and form a stable solution of the cluster aggregates (LnTOC-a). Therefore, nano-biocompatible TiO materals can be prepared from these LnTOCs just by dissolving them in water. The nanoscale aggregates in water solutions were characterized by SEI-MS, 1H NMR, XPS, IR, and EDS mapping. Using the EuTOC-a solution, excellent fluorescence sensor properties for biomolecule ascorbic acid were found. Furthermore, biocompatibility and fluorescent labeling properties of the EuTOC-a for HeLa cells were evaluated. The results indicated that water-soluble LnTOCs can be used to prepare biocompatible fluorescent Ln-Ti-O nanomaterials.

Effects of the Ligand Structures on the Photoelectric Activities, a Model Study Based on Titanium-Oxo Clusters Anchored with S-Heterocyclic Ligands.

Titanium oxo clusters (TOCs) have become one of the worldwide hot research topics because they are excellent molecular TiO materials having unique photoactive properties and can been used as models of dye-sensitized solar cells (DSSCs). S-Heterocyclic ligands such as thiophene (Th) and tetrathiafulvalene (TTF) derivatives have been widely used in electronic or photoelectronic devices and solar cells. However, a study of the synthesis and properties of TOCs anchored with Th and TTF derivatives is missing. Herein four such TOCs as single crystals were synthesized and structurally characterized: [Ti3O(OiPr)8(LTh)2] (1), [Ti4O2(OiPr)10(LTTF)2] (2), [Ti6O4(OiPr)10(LTh)2(O3PPh)2] (3), and [Ti6O4(OiPr)10(LTTF)2(O3PPh)2] (4). Charge transfer from the Th or TTF electron donor to the TOC core was evaluated by electronic spectra and theoretical calculations. This work first systematically investigated the photoelectrochemistry of TOCs with different conjugated S-heterocyclic ligands in molecular levels. The photocurrent densities of these cluster-modified TiO2 electrodes were examined using DSSCs, which were well responsive to irradiation. The photocurrents of TTF cluster-modified electrodes are higher than those of the Th cluster-modified electrodes because of the sulfur-rich conjugated system.

The YebN Leader RNA Acts as a Mn2+ Sensor Required for the Interaction of Xanthomonas oryzae and Rice.

Riboswitches are RNA elements that sense metabolites and control gene expression. Recently, the yybP-ykoY riboswitches were found to sense manganese (Mn2+) and regulate the expression of diverse genes. Here, we show that the leader RNA (a yybP-ykoY RNA) of yebN in Xanthomonas oryzae pv. oryzae also functions as a sensor of Mn2+. This leader RNA detects Mn2+ levels in plants and is essential to X. oryzae pv. oryzae virulence. Our data also indicate that Mn2+ is not only required as a microelement for plant growth but also acts as a defense molecule to inhibit pathogen growth. This finding highlights that Mn2+ plays important roles in pathogen-plant interactions and that the yebN leader RNA can be a target candidate for anti-X. oryzae pv. oryzae drug development.

The Relationship between Serum Bilirubin and Elevated Fibrotic Indices among HBV Carriers: A Cross-Sectional Study of a Chinese Population.

The study probed the association between bilirubin and hepatitis B virus (HBV) infection and progression. A cross-sectional analysis of 28,500 middle aged and elderly Chinese participants was performed to analyze the differences of bilirubin in terms of hepatitis B surface antigen (HBsAg) positive or negative and the correlation between bilirubin and severity of hepatic fibrosis estimated by non-invasive indices. Bilirubin was significantly higher in the HBsAg (+) group than the HBsAg (-) group. Higher bilirubin levels were consistently associated with elevated liver fibrosis indices among HBsAg carriers. Compared with quartile 1 of total bilirubin (TBil), the multivariable-adjusted ORs (95% CIs) for elevated fibrosis indices of quartile 4 were 2.24 (95% CIs, 1.57-3.21) estimated by fibrosis 4 score (FIB-4) and 2.22 (95% CIs, 1.60-3.08) estimated by aspartate transaminase to platelet ratio index (APRI). In addition, direct bilirubin (DBil) had a stronger association with elevated liver fibrosis indices than did indirect bilirubin (IBil). Furthermore, the relationship between DBil and elevated fibrosis indices was more robust among participants who were female, overweight or had central fat distribution. These findings suggested that bilirubin levels, especially DBil, were independently associated with an increased risk of increased fibrosis indices.