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1.
Plant Cell Rep ; 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32025802

RESUMO

KEY MESSAGE: BIG regulates the shoot stem cell population. The shoot apical meristem (SAM) contains a population of self-renewing cells, and provides daughter cells for initiation and development of aerial parts of plants. However, the underlying mechanisms of SAM size regulation remain largely unclear. Here, we identified a mutant that displayed a large SAM, designated big-shoot meristem (big-m), in Arabidopsis thaliana. The phenotype of big-m is caused by a new T-DNA insertion allele of BIG, causing a loss of function. The big-m mutant had more stem cells in the SAM than in the wild type. Expression of WUSCHEL (WUS) and SHOOTMERISTEMLESS (STM) was promoted in big-m compared with the wild type, showing that BIG functions upstream of WUS and STM. Therefore, BIG is an important regulator of the stem cell population in the SAM. Furthermore, genetic analysis indicated that BIG acts synergistically with PIN-FORMED1 (PIN1) in controlling SAM size. Our results suggest that BIG plays an important role in controlling Arabidopsis thaliana SAM growth via PIN1-mediated auxin homeostasis.

2.
Medicine (Baltimore) ; 99(6): e19030, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32028415

RESUMO

BACKGROUND: This study aimed to assess the efficacy of rigid versus foldable iris-fixed phakic intraocular lens (PIOL) implantation in the treatment of high myopia. METHODS: A systematic search based on electronic databases such as Pubmed, Embase, and Cochrane Library was conducted to identify relevant studies published up to January 11, 2019. The pooled odds ratios and weighted mean differences (WMDs) with corresponding 95% confidence intervals were calculated. RESULTS: Eight comparative studies with 835 participants were included in this meta-analysis. The overall WMD showed statistical significance in terms of postoperative uncorrected distance visual acuity (UDVA), mean postoperative spherical equivalence (SE), and mean postoperative intraocular higher-order aberrations (HOA) (µm) for a 6-mm pupil, suggesting that foldable PIOL group showed significant improvement of high myopia, compared to rigid PIOL group. Besides, compared with rigid PIOL group, foldable PIOL group had beneficial effect on the proportion of eyes with central endothelial cell density (ECD) loss in patients with high myopia. CONCLUSION: This meta-analysis provided the up-to-date evidence and found that foldable PIOL group had significant beneficial effect on UDVA, SE, HOA, contrast sensitivity, and ECD, except best spectacle-corrected visual acuity, and safety in the treatment of high myopia over rigid PIOL group.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32003526

RESUMO

Building framework materials with desirable properties and enhanced functionalities with nanocluster/superatom complexes as building blocks remains a challenge in the field of nanomaterials. Herein, the chiral [Au 1 Ag 22 (S-Adm) 12 ] 3+ nanocluster/superatom complex (SC, where S-Adm = 1-adamantanethiol) is employed as a building block to construct the 3-dimensional (3D) superatom complex inorganic framework (SCIF) materials, SCIF-1 and SCIF-2, through inorganic SbF 6 - linkers. SCIF-1 is racemic due to the assembly of two SC enantiomers in single crystal. In SCIF-2, the SC enantiomers are packed in separate crystals, which produce larger channels and a circularly polarized luminescence (CPL) response. These two 3D SCIF materials exhibit unique sensitive photoluminescence (PL) in protic solvents. Our work provides a new path for creating novel open-framework materials with superatom complexes and a foundation for the further development of 3D framework materials for sensing and other applications.

4.
Infect Dis Poverty ; 9(1): 13, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005290

RESUMO

BACKGROUND: China is facing challenges of the shifting presentation of tuberculosis (TB) from younger to elderly due to an ageing population, longer life expectancy and reactivation disease. However, the burden of elderly TB and influence factors are not yet clear. To fill the gap, we generated a cohort study to measure the magnitude of TB incidence and associated factors among the elderly population aged 65 years and above in China. METHODS: In this cohort established in 2013 through a prevalence survey conducted in selected sites, a total of 34 076 elderlies without TB were enrolled into two-year follow-up. We used both active and passive case findings to find out all TB patients among them. The person-year (PY) incidence rates for both bacteriologically positive TB and active TB were calculated. Cox proportional regression model was performed to test effect of risk factors, and the population attributable fraction (PAF) of each risk factor contributing to incident TB among elderlies was calculated. RESULTS: Over the two-year follow-up period, a total of 215 incident active TB were identified, 62 of which were bacteriologically positive. The incidence rates for active TB and bacteriologically positive TB were 481.8 per 100 000 PY (95% CI: 417.4-546.2 per 100 000 PY) and 138.9 per 100 000 PY (95% CI: 104.4-173.5 per 100 000 PY), respectively. Incident cases detected by active case finding were significantly higher (P < 0.001). Male, non-Han nationality, previously treated TB, ex/current smoker and body mass index (BMI) < 18.5 presented as independent predictors for developing TB disease. For developing bacteriologically positive TB, the biggest contribution was from self-reported ex or current smoker (18.06%). And, for developing active TB, the biggest contribution was from non-Han nationality (35.40%), followed by male (26.80%) and age at 75 years and above (10.85%). CONCLUSIONS: Ageing population in China had a high TB incidence rate and risk to develop TB disease, implying that National TB Program (NTP) needs to prioritize for elderly. Active case finding should be applied capture more active TB cases among this particular population, especially for male, non-Han nationality, and those with identified risk factors.

5.
Int J Mol Sci ; 21(4)2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32054031

RESUMO

Lung cancer is one of the most malignant cancers around the world, with high morbidity and mortality. Metastasis is the leading cause of lung cancer deaths and treatment failure. MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs), two groups of small non-coding RNAs (nc-RNAs), are confirmed to be lung cancer oncogenes or suppressors. Transforming growth factor-ß (TGF-ß) critically regulates lung cancer metastasis. In this review, we summarize the dual roles of miRNAs and lncRNAs in TGF-ß signaling-regulated lung cancer epithelial-mesenchymal transition (EMT), invasion, migration, stemness, and metastasis. In addition, lncRNAs, competing endogenous RNAs (ceRNAs), and circular RNAs (circRNAs) can act as miRNA sponges to suppress miRNAs, thereby mediating TGF-ß signaling-regulated lung cancer invasion, migration, and metastasis. Through this review, we hope to cast light on the regulatory mechanisms of miRNAs and lncRNAs in TGF-ß signaling-regulated lung cancer metastasis and provide new insights for lung cancer treatment.

6.
Biomed Pharmacother ; 125: 109896, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32007918

RESUMO

Cisplatin (DDP) is the first-line drug for the treatment of gastric cancer (GC). However, DDP resistance is common. Autophagy, which is closely related to chemoresistance, is a process of resolving and recycling proteins and damaged cellular organs. Additionally, O-6-methylguanine-DNA methyltransferase (MGMT) is responsible for alkylating drug resistance. However, the relationship between autophagy and MGMT in response to DDP in GC is still unknown. In the present study, we determined that autophagy induced by DDP decreases chemosensitivity in GC cell lines. DDP may have induced autophagy in GC by inhibiting MGMT to increase autophagy-related gene (ATG) 4B. Inhibition of MGMT-mediated ATG4B suppression resulted in autophagy induction and DDP resistance. In vivo, combined DDP and autophagy inhibitor chloroquine (CQ) enhanced the anti-tumor effect of DDP; additionally, the negative correlation of MGMT and ATG4B was confirmed. High expression of MGMT and low expression of ATG4B were significantly correlated with favorable five-year survival rate (P < 0.05) in 66 clinicopathologically characterized GC cases. Our study demonstrate that DDP inhibits MGMT-mediated autophagy suppression to decrease chemosensitivity in GC, which provides a novel therapeutic strategy to promote DDP chemosensitivity in GC.

7.
World J Gastroenterol ; 26(1): 35-54, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31933513

RESUMO

BACKGROUND: Abdominal paracentesis drainage (APD) is a safe and effective strategy for severe acute pancreatitis (SAP) patients. However, the effects of APD treatment on SAP-associated cardiac injury remain unknown. AIM: To investigate the protective effects of APD on SAP-associated cardiac injury and the underlying mechanisms. METHODS: SAP was induced by 5% sodium taurocholate retrograde injection in Sprague-Dawley rats. APD was performed by inserting a drainage tube with a vacuum ball into the lower right abdomen of the rats immediately after SAP induction. Morphological staining, serum amylase and inflammatory mediators, serum and ascites high mobility group box (HMGB) 1, cardiac-related enzymes indexes and cardiac function, oxidative stress markers and apoptosis and associated proteins were assessed in the myocardium in SAP rats. Nicotinamide adenine dinucleotide phosphate oxidase activity and mRNA and protein expression were also examined. RESULTS: APD treatment improved cardiac morphological changes, inhibited cardiac dysfunction, decreased cardiac enzymes and reduced cardiomyocyte apoptosis, proapoptotic Bax and cleaved caspase-3 protein levels. APD significantly decreased serum levels of HMGB1, inhibited nicotinamide adenine dinucleotide phosphate oxidase expression and ultimately alleviated cardiac oxidative injury. Furthermore, the activation of cardiac nicotinamide adenine dinucleotide phosphate oxidase by pancreatitis-associated ascitic fluid intraperitoneal injection was effectively inhibited by adding anti-HMGB1 neutralizing antibody in rats with mild acute pancreatitis. CONCLUSION: APD treatment could exert cardioprotective effects on SAP-associated cardiac injury through suppressing HMGB1-mediated oxidative stress, which may be a novel mechanism behind the effectiveness of APD on SAP.

8.
Colloids Surf B Biointerfaces ; 188: 110797, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31958621

RESUMO

A novel non-enzymatic glucose sensor was established by galvanic replacement synthesis of Pd nanosheets (PdNS) on Cu/Cu2O nanocomposites using fluorine-doped tin oxide (FTO) substrates. To prepare PdNS-Cu/Cu2O/FTO electrode, Cu/Cu2O nanocomposites were firstly deposited on FTO electrode through potential oscillating, and then Pd nanosheets were synthesized on Cu/Cu2O nanocomposites by galvanic replacement reduction. X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy were applied to investigate the morphology and composition of PdNS-Cu/Cu2O nanohybrids. The synthesized PdNS-Cu/Cu2O exhibited great electrochemical activity toward glucose oxidation. Under optimized conditions, the proposed glucose sensor displayed a wide linear range from 0.5 µM to 2600 µM with detection limit of 0.1 µM. In addition, the proposed electrode was used to determine glucose in true blood specimen, indicating potential application for routine glucose analysis.

9.
Cancer Lett ; 474: 15-22, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31917160

RESUMO

The gut microbiota forms a symbiotic relationship with the host and benefits the body in many critical aspects of life. However, immune system defects, alterations in the gut microbiota and environmental changes can destroy this symbiotic relationship and may lead to diseases, including cancer. Due to the anatomic and functional connection of the gut and liver, increasing studies show the important role of the gut microbiota in the carcinogenesis of hepatocellular carcinoma (HCC). In this manuscript, we review the available evidence and analyze some potential mechanisms of the gut microbiota, including bacterial dysbiosis, lipopolysaccharide (LPS), and genotoxins, in the progression and promotion of HCC. Furthermore, we discuss the possible therapeutic applications of probiotics, chemotherapy modulation, immunotherapy, targeted drugs and fecal microbiota transplantation (FMT) in targeting the gut microbiota.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31912328

RESUMO

PURPOSE: Osteoporosis and fragility fracture are major bone toxicities of aromatase inhibitors (AIs) for postmenopausal hormone receptor-positive breast cancer. Except for a few small studies on bone turnover markers and reduced bone mineral density after AI treatment, data on the associations of bone markers and risk of osteoporosis or fracture from prospective studies are lacking. METHODS: In a prospective study of 1709 women on AIs, two bone turnover markers, BALP and TRACP, and two bone regulatory markers, RANKL and OPG, were measured and examined in relation to risk of osteoporosis and fragility fractures during a median follow-up time of 6.1 years. RESULTS: Higher levels of BALP and TRACP were both associated with increased risk of osteoporosis and higher BALP/TRACP ratios were associated with lower risk of osteoporosis, but no associations were observed for fracture risk. Higher levels of OPG were associated with increased risk of fracture, whereas higher levels of RANKL were associated with lower risk. As a result, OPG/RANKL ratios were positively associated with fracture risk [hazard ratio (HR) = 2.49, 95% confidence interval (CI) 1.34-4.61]. After controlling for age and fracture history, the associations became non-significant but a suggestive trend remained (HR = 1.80, 95% CI 0.96-3.37). CONCLUSION: Our study provides suggestive evidence for the potential utility of OPG/RANKL ratios in predicting risk of fracture in women treated with AIs for breast cancer. Further validation may be warranted.

11.
Telemed J E Health ; 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31928505

RESUMO

Abstract Background/Introduction: The quality of maternal health care service is a crucial determinant of maternal morbidities and mortalities. This study aimed to explore feasibility and relative efficacy of WeChat (WC), of specialist team (ST) service, and of combined of both interventions (WC-ST) for improving the quality of maternal health care in China. Materials and Methods: A four-arm randomized controlled trial of 1,400 pregnant women was conducted in three hospitals in Chengdu, Southwest China, from December 2016 to October 2017. Eligible women were randomly assigned to either of three intervention groups or the control group (service as usual; SAU). Main outcome measures were satisfaction rate and uptakes of maternal health care service at 49 days postpartum based on questionnaire survey. Results: No significant differences in satisfaction rate were found among four groups at baseline (p = 0.981), and significant group differences were noted at 49 days postpartum (p < 0.001), with the highest rate from WC-ST group (98.6%), followed by that of ST (95.2%) and WC (91.6%) groups, and SAU group being the lowest (85.2%). The same pattern of group difference was observed in measures of health care uptake behaviors. Most health care uptake measures from the baseline to post-trial were significantly improved within each of the intervention groups, while most such measures in the control group were not different from baseline to post-trial. Discussion and Conclusions: The WC and ST service is feasible and potentially effective in improving the quality of maternal health care service in China. The study has revealed limitations and options for improvement in future main trial.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31905370

RESUMO

There is a close relationship between serotonergic (5-HT) activity and anxiety. ErbB4, a receptor tyrosine kinase, is expressed in 5-HT neurons. However, whether ErbB4 regulates 5-HT neuronal function and anxiety-related behaviors is unclear. Here, using transgenic and viral approaches, we show that mice with ErbB4 deficiency in 5-HT neurons exhibit heightened anxiety-like behavior and impaired fear extinction, possibly due to an increased excitability of 5-HT neurons in the dorsal raphe nucleus (DRN). Notably, the chemogenetic inhibition of 5-HT neurons in the DRN of ErbB4 mutant mice rescues anxiety-like behaviors. Altogether, our results unravel a previously unknown role of ErbB4 signaling in the regulation of DRN 5-HT neuronal function and anxiety-like behaviors, providing novel insights into the treatment of anxiety disorders.

13.
Chem Commun (Camb) ; 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31909401

RESUMO

Cubic perovskite-type Sm0.3Sr0.7Nb0.08Co0.92O3-δ (SSNC) demonstrated excellent oxygen reduction reaction (ORR) activity at 600 °C due to a high concentration and high mobility of oxygen vacancies, which were derived from the low average cobalt valence and cubic structure in SSNC at room temperature.

14.
Life Sci ; 243: 117277, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31926252

RESUMO

AIMS: This study aimed to investigate the characteristics and mechanism of autophagy on podocyte apoptosis under high glucose (HG) conditions and further explore the effect of berberine on podocyte autophagy, apoptosis and the potential mechanism. MATERIALS AND METHODS: The levels of LC3II/I in podocytes stimulated with HG were detected at 0, 2, 4, 8, 12, 24, 36 and 48 h by western blotting. CCK-8 was used to detect the viability of podocytes. The level of autophagy was detected by western blotting, transmission electron microscopy and immunofluorescence. Podocyte apoptosis was analysed by using Hoechst staining, western blotting, annexin V/propidium iodide dual staining, and confocal microscopy. Then, podocytes were transfected with siRNA to silence mTOR, and the expression levels of proteins and mRNA involved in the mTOR/P70S6K/4EBP1 pathway were further investigated by western blotting and qRT-PCR. KEY FINDINGS: In this study, we found significantly reduced LC3II/LC3I and increased p62 in podocytes stimulated with HG for 24 h, and the level of autophagy reached a minimum at 24 h. Berberine restored podocyte viability and significantly attenuated HG-mediated inhibition of autophagy, as evidenced by the increased expression of LC3II/LC3I, the number of autophagosomes and the inhibition of p62. Moreover, berberine counteracted HG-induced podocyte apoptosis and injury, which was negatively correlated with the autophagy effect. Notably, silencing mTOR with siRNA augmented the inhibition of P70S6k and 4EBP1 phosphorylation, which was similar to the effect of berberine. SIGNIFICANCE: Berberine activates podocyte autophagy by inhibiting the mTOR/P70S6K/4EBP1 signaling pathway, thereby alleviating podocyte apoptosis.

15.
Nephrol Dial Transplant ; 35(1): 155-161, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30304540

RESUMO

BACKGROUND: The 2017 high blood pressure (BP) clinical practice guideline reported by the American College of Cardiology/American Heart Association put forward new categories of BP. This study aimed to assess the applicability of the new guideline in a nondialysis chronic kidney disease (CKD) population. METHODS: This is a nationwide, multicenter, cross-sectional study with a large sample. A total of 8927 nondialysis CKD patients in 61 tertiary hospitals in all 31 provinces, municipalities and autonomous regions of China (except Hong Kong, Macao and Taiwan) were analyzed. The categories of BP were defined as normal BP (<120/80 mmHg), elevated BP [systolic BP (SBP) 120-130 and diastolic BP (DBP) <80 mmHg], and Stage 1 (SBP 130-139 or DBP 80-89 mmHg) and Stage 2 (SBP ≥140 or DBP ≥90 mmHg) hypertension. The prevalence and control of hypertension were estimated using a new definition, and the association between the main target organs' injury and new categories of BP was analyzed. RESULTS: The prevalence, awareness and treatment of hypertension in nondialysis CKD patients were 79.8, 72.4 and 68.3%, respectively. Approximately 11.9% had BP <130/80 mmHg and 6.6% had BP <120/80 mmHg. Subgroups by categories of BP had significant differences in age, sex, body mass index category, primary cause and CKD stage (P < 0.001). After multivariable adjustment, only Stage 2 hypertension was associated with decreased renal function [odds ratio (OR) 2.4, 95% confidence interval (CI) 1.9-3.0, P < 0.001], cardiovascular disease (OR 2.0, 95% CI 1.3-3.1, P = 0.001) and cerebrovascular disease (OR 2.7, 95% CI 1.2-5.8, P = 0.015). CONCLUSIONS: Using the new definition of hypertension, the higher prevalence and lower control of hypertension were shown in nondialysis CKD participants. More studies are necessary to confirm the applicability of new categories of BP in CKD population because only Stage 2 hypertension showed statistical association with the main target organs' injury.

16.
Parasitol Res ; 119(2): 637-647, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31823007

RESUMO

The trichomonad species Tetratrichomonas buttreyi and Pentatrichomonas hominis have been reported in the bovine digestive tract in only a few studies, and the prevalence and pathogenicity of these two protists in cattle herds remain unknown. In this study, the prevalence of T. buttreyi and P. hominis in yellow cattle, dairy cattle, and water buffalo in Anhui Province, China, was determined with a PCR analysis of the small subunit ribosomal RNA genes. The overall infection rates for T. buttreyi and P. hominis were 8.1% and 5.4%, respectively. Double infections were found in 15 (1.6%) samples from four farms. The prevalence of P. hominis in cattle with abnormal feces was significantly higher than that in cattle with normal feces (χ2 = 13.0, p < 0.01), and the prevalence of T. buttreyi in the northern region of Anhui Province was also significantly higher than that in the mid region (χ2 = 16.6, p < 0.01). Minor allelic variations were detected in the T. buttreyi isolates from cattle in this study, as in other hosts in previous studies. Morphological observations, together with the PCR analysis, demonstrated that the trichomonads isolated in this study were P. hominis. The presence of T. buttreyi and P. hominis indicated that cattle are natural hosts of these two trichomonads and could be a potential source of P. hominis infections in humans and other animal hosts.

17.
Anal Chem ; 92(1): 932-939, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31756083

RESUMO

This study, for the first time, predicts oxidative stability in camellia oils by partial least squares (PLS) built with proton nuclear magnetic resonance (1H NMR) and α-tocopherol content. The prediction models were established by the PLS method. Outlier detection, latent variables optimization, data pretreatment, and important variables selection were applied for models optimization. All the developed models exhibited good performance as indicated by R2 > 0.895 and root mean square error of estimation and root mean square error of prediction less than 0.322 and 0.307. For verification of the contribution of 1H NMR spectra and α-tocopherol for prediction performance, a PLS model with fatty acids composition instead of 1H NMR spectra and one with only 1H NMR spectra as input variables were developed, respectively. The results showed that the model based on 1H NMR data was more accurate and precise than that based on fatty acid composition data. And the performance of the models was significantly degraded without α-tocopherol as input variables.

18.
Thyroid ; 30(1): 95-105, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31650898

RESUMO

Background: Overt thyroid diseases have been identified as risk factors for female infertility. However, it remains largely unclear whether subclinical hypothyroidism (SCH), a very common thyroid disorder, is associated with female infertility. This study aimed to investigate the potential association between SCH and the ovarian reserve in women seeking infertility treatment. Methods: This retrospective study included 2568 women with normal thyroid function (n = 2279) or SCH (n = 289) who visited our clinic for infertility treatment. Ovarian reserve markers, including follicle-stimulating hormone (FSH) concentrations on days 2-4, the antral follicle count (AFC), and anti-Müllerian hormone (AMH) concentration, were compared between euthyroid women and those with SCH. Multiple linear and Poisson regression analyses were used to estimate the associations of SCH with ovarian reserve markers. These analyses were repeated separately in women aged <35 (n = 1349) and ≥35 years (n = 1219). Results: In the total study population, women with SCH had significantly lower AMH concentrations (median: 2.05 vs. 2.51 ng/mL, p = 0.015) and AFCs (median: 10.0 vs. 11.0, p = 0.013), compared with euthyroid women. In linear and Poisson regression analyses, SCH was significantly associated with a higher basal FSH concentration (mean difference = 1.13 mIU/mL [95% confidence interval (CI) 0.97 to 1.29 mIU/mL], p < 0.001), lower AMH concentration (mean difference = -0.27 ng/mL [CI -0.43 to -0.12 ng/mL], p = 0.001), and lower AFC (mean difference = -0.7 [CI -1.3 to -0.2], p = 0.005). In women aged ≥35 years, SCH was significantly associated with FSH (mean difference = 1.74 mIU/mL, p < 0.001) and AMH concentrations (mean difference = -0.40 mg/mL, p < 0.001) and AFC (mean difference = -0.8, p < 0.001). In women <35 years old, SCH was significantly associated with a higher FSH concentration (mean difference = 0.30 mIU/mL, p < 0.001), but not with AMH or AFC concentrations (p = 0.84 and 0.06, respectively). Thyroperoxidase antibody (TPOAb) positivity was not associated with measures of ovarian reserve. Conclusions: The data suggest that SCH is associated with decreased ovarian reserve during later reproductive age. TPOAb positivity was not associated with ovarian reserve. Future research is necessary to investigate the underlying molecular mechanisms regulating the diminished ovarian reserve in women with SCH and to evaluate whether levothyroxine supplementation may improve the ovarian function of women with SCH.

19.
Water Res ; 169: 115249, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31706128

RESUMO

The increasing use of perfluorooctanoic acid (PFOA) raises concerns about its potential toxicity to the environment. However, the interaction between PFOA and aerobic granular sludge has never been documented. This work therefore aims to provide such support through investigating the fate of PFOA at environmentally relevant levels in aerobic granular sludge systems and its impact on aerobic granular sludge. Experimental results showed that 32.0%∼36.4% of wastewater PFOA was removed by aerobic granular sludge in stable operation when PFOA concentration was ranged from 0.1 to 1.0 mg/L. Mass balance analyses and X-ray photoelectron spectroscopy survey scan revealed that the removal of PFOA was dominated by adsorption rather than biodegradation, and sorption kinetic analysis indicated that inhomogeneous multilayer adsorption was responsible for this removal. The adsorbed PFOA deteriorated the settleability of granular sludge and biological nitrogen and phosphorus removal significantly. Experimental results showed that 1.0 mg/L PFOA inhibited anaerobic phosphate release, aerobic phosphate uptake, nitrate reduction, and nitrite reduction processes by 60%, 50%, 13.1%, and 5.8%, respectively. It was observed that PFOA induced large amounts of filamentous villus growing on the surface and increased the extracellular polymeric substances of granular sludge. Fourier-transform infrared spectra and X-ray photoelectron spectroscopy spectrum showed that several function groups in extracellular polymeric substances such as hydroxyl groups, amides and polysaccharides were affected by PFOA. It was also found that PFOA inhibited the cyclic transformations of polyhydroxyalkanoates and glycogen. Microbial community analyses showed that PFOA decreased the abundances of Nitrosomonas, Nitrospira, Accumulibacter, and other function microbes such as Rhodospirillaceae, Thauera, and Azoarcus.


Assuntos
Esgotos , Eliminação de Resíduos Líquidos , Aerobiose , Reatores Biológicos , Caprilatos , Fluorcarbonetos , Cinética , Nitrogênio
20.
Am J Physiol Gastrointest Liver Physiol ; 318(1): G162-G173, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31604033

RESUMO

Hepatitis B virus (HBV) exploits multiple strategies to evade host immune surveillance. Programmed cell death 1 (PD-1)/programmed death ligand 1 (PD-L1) signaling plays a critical role in regulating T cell homeostasis. However, it remains largely unknown as to how HBV infection elevates PD-L1 expression in hepatocytes. A mouse model of HBV infection was established by hydrodynamic injection with a vector containing 1.3-fold overlength HBV genome (pHBV1.3) via the tail vein. Coculture experiments with HBV-expressing hepatoma cells and Jurkat T cells were established in vitro. We observed significant decrease in the expression of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and increase in ß-catenin/PD-L1 expression in liver tissues from patients with chronic hepatitis B and mice subjected to pHBV1.3 hydrodynamic injection. Mechanistically, decrease in PTEN enhanced ß-catenin/c-Myc signaling and PD-L1 expression in HBV-expressing hepatoma cells, which in turn augmented PD-1 expression, lowered IL-2 secretion, and induced T cell apoptosis. However, ß-catenin disruption inhibited PTEN-mediated PD-L1 expression, which was accompanied by decreased PD-1 expression, and increased IL-2 production in T cells. Luciferase reporter assays revealed that c-Myc stimulated transcriptional activity of PD-L1. In addition, HBV X protein (HBx) and HBV polymerase (HBp) contributed to PTEN downregulation and ß-catenin/PD-L1 upregulation. Strikingly, PTEN overexpression in hepatocytes inhibited ß-catenin/PD-L1 signaling and promoted HBV clearance in vivo. Our findings suggest that HBV-triggered PTEN/ß-catenin/c-Myc signaling via HBx and HBp enhances PD-L1 expression, leading to inhibition of T cell response, and promotes HBV immune evasion.NEW & NOTEWORTHY This study demonstrates that during HBV infection, HBV can increase PD-L1 expression via PTEN/ß-catenin/c-Myc signaling pathway, which in turn inhibits T cell response and ultimately promotes HBV immune evasion. Targeting this signaling pathway is a potential strategy for immunotherapy of chronic hepatitis B.

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