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1.
Br J Nutr ; : 1-32, 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32213215

RESUMO

Previous studies have shown conflicting findings regarding the relationship between maternal vitamin D deficiency (VDD) and foetal growth restriction (FGR). We hypothesized that parathyroid hormone (PTH) may be an underlying factor relevant to this potential association. In a prospective birth cohort study, descriptive statistics were evaluated for the demographic characteristics of 3407 pregnancies in the second trimester from three antenatal clinics in Hefei, China. The association of the combined status of VD and PTH with birth weight and the risk of small for gestational age (SGA) was assessed by a multivariate linear and binary logistic regression. We found that declined status of 25(OH) D are associated with the lower birth weight (for moderate VDD : adjusted ß=-49.4 g, 95% CI: -91.1, -7.8, P <0.05; for severe VDD: adjusted ß=-79.8 g, 95% CI: -127.2, -32.5, P <0.01), as well as ascended levels of PTH (for elevated PTH: adjusted ß=-44.5 g, 95% CI: -82.6, -6.4, P <0.05). Compared to the non-VDD group with non-elevated PTH, pregnancies with severe VDD and elevated PTH had the lowest neonatal birthweight (adjusted ß=-124.7 g, 95% CI: -194.6, -54.8, P <0.001) and the highest risk of SGA (adjusted RR=3.36, 95% CI: 1.41, 8.03, P <0.01). Notably, the highest risk of less calcium supplementation were founded in severe VDD group with elevated PTH (adjusted RR=4.67, 95% CI: 2.78, 7.85, P <0.001).In conclusion, elevated PTH induced by less calcium supplementation would further aggravate the risk of FGR in pregnancies with severe VDD through impaired maternal calcium metabolism homeostasis.

2.
BMC Nephrol ; 21(1): 90, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32156263

RESUMO

BACKGROUND: DD was found to be associated with acute myocardial infarction (AMI) and renal insufficiency. However, it is uncertain whether DD is an independent risk factor of CI-AKI in patients undergoing pPCI. METHODS: We prospectively enrolled 550 consecutive patients with STEMI undergoing pPCI between January 2012 and December 2016. The predictive value of admission DD for CI-AKI was assessed by receiver operating characteristic (ROC) and multivariable logistic regression analysis. CI-AKI was defined as an absolute serum creatinine increase ≥0.3 mg/dl or a relative increase in serum creatinine ≥50% within 48 h of contrast medium exposure. RESULTS: Overall, the incidence of CI-AKI was 13.1%. The ROC analysis showed that the cutoff point of DD was 0.69 µg/ml for predicting CI-AKI with a sensitivity of 77.8% and a specificity of 57.3%. The predictive value of DD was similar to the Mehran score for CI-AKI (AUCDD = 0.729 vs AUCMehran = 0.722; p = 0.8298). Multivariate logistic regression analysis indicated that DD > 0.69 µg/ml was an independent predictor of CI-AKI (odds ratio [OR] = 3.37,95% CI:1.80-6.33, p < 0.0001). Furthermore, DD > 0.69 µg/ml was associated with an increased risk of long-term mortality during a mean follow-up period of 16 months (hazard ratio = 3.41, 95%CI:1.4-8.03, p = 0.005). CONCLUSION: Admission DD > 0.69 µg/ml was a significant and independent predictor of CI-AKI and long-term mortality in patients undergoing pPCI.

3.
Biochem Biophys Res Commun ; 525(2): 512-519, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32113679

RESUMO

Endothelial inflammation is an important contributor to the pathology of atherosclerotic cardiovascular disease (ASCVD). Circular RNAs (circRNAs) function and role in endothelium inflammation still unknown. In our present study, we firstly identified that circ-RELL1 plays a proinflammatory role in ox-LDL-induced HUVECs through high-throughput circRNA microarray assays. Knockdown circ-RELL1 can reduce the expression of ICAM1 and VCAM1 in ox-LDL induced endothelium inflammation. Mechanistically, circ-RELL1 directly bound to miR-6873-3p in cytoplasm. Subsequently miR-6873-3p reduced MyD88 (myeloid differentiation primary response 88) protein expression and alleviated MyD88 medicated NF-κB activation. Furthermore, circ-RELL1 can abolish the inhibition of inflammation response by miR-6873-3p. Our findings illustrate a novel regulatory pathway that circ-RELL1 modulate inflammatory response by miR-6873-3p/MyD88/NF-κB axis in ox-LDL induced endothelial cells, which provides a potential therapeutic candidate for endothelium inflammation in atherosclerotic cardiovascular disease.

4.
Ecotoxicol Environ Saf ; 195: 110437, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32193020

RESUMO

More research about branch order-specific accumulation of toxic ions in root systems is needed to know root branch-related responses in growth and physiology. In this study, we used Populus deltoides females and males as a model to detect sex-specific differences in physiology, biochemistry, ultrastructure of absorbing roots and distribution of toxic ions in heterogeneous root systems under Cd, salinity and combined stress. Healthy annual male and female plants of P. deltoides were cultivated in soils including 5 mg kg-1 of Cd, 0.2% (w/w) of NaCl and their combination for a growth season. Our results are mainly as follows: (1) females suffered more growth inhibition, root biomass decline, root viability depression, and damage to distal root cells, but lower ability to scavenge reactive oxygen species (ROS) than the males under all stresses; (2) In both sexes, salinity adopted in the present study caused more significant negative effects on growth and organelles integrity than Cd stress, while interaction treatment did not induced a further depression in growth or more impairments in root cells of both sexes in comparison to salinity, indicating influence of combined stress was not equal simply to a superposition of the effects caused by single factors; (3) Cd and Na accumulation in root systems is highly heterogeneous and branch order-specific, with lower-order roots containing more Cd2+ but less Na+, and higher-order roots accumulating more Na+ but less Cd2+. Besides, it is noteworthy that females accumulated more Cd2+ in 1-2 order roots and more Na+ in 1-3 order roots than males under the interaction treatment. These results indicated that strategies in toxic ions accumulation in heterogeneous root systems of P. deltoides was highly branch order-specific, and may closely correlate with sex-specific root growth and physiological responses to the interaction of Cd and salinity.

5.
CNS Neurosci Ther ; 2020 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-32087606

RESUMO

BACKGROUND AND PURPOSE: Cerebral organoids (COs) have been used for studying brain development, neural disorders, and species-specific drug pharmacology and toxicology, but the potential of COs transplantation therapy for brain injury remains to be answered. METHODS: With preparation of traumatic brain injury (TBI) model of motor dysfunction, COs at 55 and 85 days (55 and 85 d-CO) were transplanted into damaged motor cortex separately to identify better transplantation donor for brain injury. Further, the feasibility, effectiveness, and underlying mechanism of COs transplantation therapy for brain injury were explored. RESULTS: 55 d-CO was demonstrated as better transplantation donor than 85 d-CO, evidenced by more neurogenesis and higher cell survival rate without aggravating apoptosis and inflammation after transplantation into damaged motor cortex. Cells from transplanted COs had the potential of multilinage differentiation to mimic in-vivo brain cortical development, support region-specific reconstruction of damaged motor cortex, form neurotransmitter-related neurons, and migrate into different brain regions along corpus callosum. Moreover, COs transplantation upregulated hippocampal neural connection proteins and neurotrophic factors. Notably, COs transplantation improved neurological motor function and reduced brain damage. CONCLUSIONS: This study revealed 55 d-CO as better transplantation donor and demonstrated the feasibility and efficacy of COs transplantation in TBI, hoping to provide first-hand preclinical evidence of COs transplantation for brain injury.

6.
Microb Pathog ; 142: 104043, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32032768

RESUMO

Cherax quadricarinatus is seriously affected by multiple types of pathogens, including bacteria and viruses, and has been widely transplanted around the world. Heat shock proteins (Hsps) are a group of molecular chaperones that play important roles in promoting the proper refolding and blocking the aggregation of denatured proteins. In this study, CqHsp60, CqHsp70 and CqHsp90 from C. quadricarinatus were cloned, and their expression patterns were analysed. The CDS (coding sequence) lengths of the CqHsp60, CqHsp70 and CqHsp90 genes were 1731 bp, 1932 bp and 2199 bp, encoding 576, 643 and 732 amino acids, respectively. CqHsp60 was 99.13%, 98.78% and 88.63% identical to the corresponding sequences of Cherax cainii, Cherax destructor and Eriocheir sinensis, respectively. CqHsp70 showed 99.84%, 92.73% and 91.58% identity to the corresponding sequences of C. cainii, C. destructor and E. sinensis, while CqHsp90 was 98.25%, 98.51% and 91.41% identical with those of C. cainii, C. destructor and E. sinensis, respectively. The expression patterns of the three CqHsps were different between males and females. CqHsp60 and CqHsp70 exhibited the highest expression in the hepatopancreas of males and the gonads of females, and CqHsp90 presented the highest expression in the gonads of males and hepatopancreas of females. After pathogenic inoculation, the death trend of C. quadricarinatus at different time points was the same in association with different pathogens, with most deaths occurring within 6 h post-inoculation. The trend of CqHsp transcription at different time points was the same among the groups treated with Vibrio alginolyticus, Vibrio parahemolyticus and Aeromonas hydrophila, exhibiting upregulation first and then downregulation. The expression of CqHsp60 and CqHsp70 in the gills of living C. quadricarinatus was less than 3.5 times that in the PBS group, but in the gills of dead C. quadricarinatus under A. hydrophila inoculation, its expression was more than 5-9 times that in the PBS group. CqHsp90 expression changed dramatically in the V. alginolyticus, V. parahemolyticus and A. hydrophila groups, in which it exceeded 50 times the level in the PBS group. These results indicated that CqHsps could induce the activation of the immune system within a short time and that CqHsp90 could be used as a more effective molecular biomarker than CqHsp70 and CqHsp60 in a pathogenic bacterium-polluted environment.

7.
Int J Syst Evol Microbiol ; 70(3): 1800-1804, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31951192

RESUMO

A novel Streptomyces strain (SSL-25T) was isolated from mangrove soil sampled at QinzhouBay, PR China. The isolate was observed to be Gram-stain-positive and to form greyish-white aerial mycelia that differentiated into straight spore chains with smooth-surfaced spores on International Streptomyces Project 2 medium. The cell-wall peptidoglycan was determined to contain ll-diaminopimelicacid. The cell-wall sugars were glucose and mannose. The predominant menaquinones were MK-9 (H6), MK-9 (H8) and MK-9 (H4). The major polar lipids contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannoside and several unidentified phospholipids. The predominant cellular fatty acids were C16:0, iso-C16:0 and summed feature 3 (C16:1ω7c/C16:1ω6c). The genome size of strain SSL-25T was 8.1 Mbp with a G+C content of 71.5 mol%. Phylogenetic analysis indicated that strain SSL-25T is closely related to Streptomyces tsukubensis NRRL 18488T (99.4 % sequence similarity). However, the digital DNA-DNA hybridization (39.8 %) and average nucleotide identity (91.3 %) values between them showed that it represents a distinct species. Furthermore, the results of morphological, physiological and biochemical tests allowed further phenotypic differentiation of strain SSL-25T from S. tsukubensis NRRL 18488T. Therefore, based on these results, it is concluded that strain SSL-25T represents a novel Streptomyces species, for which the name Streptomyces qinzhouensis sp. nov. is proposed. The type strain is SSL-25T (=CICC 11054T=JCM33585T).

8.
Sci Total Environ ; 704: 135413, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31896227

RESUMO

Mountain glaciers retreat at an increased rate under global warming, resulting in exposed barren surfaces for primary succession. Soil microbes are an important driver of ecosystem processes. Although variations in soil microbes after deglaciation have been studied extensively, the roles of rhizosphere soil microbes in the biogeochemistry cycle during primary succession are less understood. In this study, Populus purdomii was present throughout the 123-year chronosequence as a representative tree species. We therefore investigated variations in the rhizosphere enzyme activity, microbial community structure, and ecoenzymatic stoichiometry of P. purdomii along Hailuogou Glacier chronosequences. The objective was to determinechanges in rhizosphere enzyme activities and microbial communities, as well as the effects of nutrient limitation on rhizosphere microbes. According to the results, the enzyme activities and microbial group biomass in rhizosphere soil all showed a bimodal trend and were highest at the 43rd or 123rd year, and enzyme activity varied with succession time but not microbial community structure. The rhizosphere soil bacterial community was the dominant community during the 123-year chronosequence. Ecoenzymatic stoichiometry indicated nitrogen restrictions on microbial activity throughout primary succession, with early succession stages (5-15 years) showing greater carbon restriction than late succession stages. Moreover, redundancy and correlation analyses demonstrated that soil microbial phospholipid fatty acid biomass was an important factor for increases in enzyme activities and that enzyme activities in turn played important roles in carbon, nitrogen and phosphorus cycling in rhizosphere soil. Additionally, rhizosphere soil microbial development significantly affected soil organic carbon, total nitrogen and dissolved organic carbon accumulation. Overall, our study links the rhizosphere microbial community and activity to successional chronosequences, providing a deeper understanding of the dynamics of ecosystem succession.


Assuntos
Camada de Gelo , Rizosfera , Carbono , Ecossistema , Nitrogênio , Nutrientes , Solo , Microbiologia do Solo
9.
Neuroscience ; 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31982470

RESUMO

OBJECTIVE: The spontaneous action potential of isolated sinoatrial node (SAN) cells is regulated by a coupled-clock system of two clocks: the calcium clock and membrane clock. However, it remains unclear whether calcium clock inhibitors have a direct effect on the membrane clock. The purpose of this study was to investigate the direct effect of cyclopiazonic acid (CPA), a selective calcium clock inhibitor, on the function of the membrane clock of SAN cells. METHODS: at SAN cells were isolated by trypsinization and identified based on morphology and electrophysiology. If and HCN currents were recorded via patch clamp technique. The expression of the HCN channel protein was determined by Western blotting analysis. RESULTS: The diastolic depolarization rate of spontaneous action potentials and the current densities of If were reduced by exposure to 10 µM CPA. The inhibitory effect of CPA was concentration-dependent with an IC50 value of 16.3 µM and a Hill coefficient of 0.98. The effect of CPA on If current was also time-dependent, and the If current amplitude was partially restored after washout. Furthermore, the steady-state activation curve of the If current was shifted to a negative potential, indicating that channel activation slowed down. Finally, the protein expression of HCN4 in HEK293 cells was markedly downregulated by CPA. CONCLUSIONS: These results indicate that the direct inhibition effect of CPA on the If current in SAN cells is both concentration- and time-dependent. The underlying mechanisms may involve slowing down steady-state activation and the downregulation of pacemaker channel protein expression.

10.
Hepatology ; 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31903610

RESUMO

Transforming growth factor beta (TGF-ß) suppresses early stages of tumorigenesis, but contributes to migration and metastasis of cancer cells. However, the role of TGF-ß signaling in invasive prometastatic hepatocellular carcinoma (HCC) is poorly understood. In this study, we investigated the roles of canonical TGF-ß/SMAD3 signaling and identified downstream effectors on HCC migration and metastasis. By using in vitro trans-well migration and invasion assays and in vivo metastasis models, we demonstrated that SMAD3 and Protein Tyrosine Phosphatase Receptor Epsilon (PTPRε) promotes migration, invasion and metastasis of HCC cells in vitro and in vivo. Further mechanistic studies revealed that, upon TGF-ß stimulation, SMAD3 binds directly to PTPRε promoters to activate its expression. PTPRε interacts with TGFBR1/SMAD3 and facilitates recruitment of SMAD3 to TGFBR1, resulting a sustained SMAD3 activation status. The tyrosine phosphatase activity of PTPRε is important for binding with TGFBR1, recruitment and activation of SMAD3, and its prometastatic role in vitro. A positive correlation between pSMAD3/SMAD3 and PTPRε expression were determined in HCC samples, and high expression of SMAD3 or PTPRε was associated with poor prognosis of HCC patients. Conclusion PTPRε positively feedback regulates TGF-ß/SMAD3 signaling to promote HCC metastasis.

11.
J Cardiothorac Surg ; 15(1): 20, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31937330

RESUMO

OBJECTIVE: The percutaneous closure of a single secundum atrial septal defect (ASD) under transesophageal echocardiography guidance as an accepted alternative to the transcatheter closure with fluoroscopy has been proven. However, the technique has not been routinely used. This study was to present and share our experience in comparing the clinical outcomes of the percutaneous and intra-operative device closure (IODC) of atrial septal defects without fluoroscopy. METHODS: From January 2013 to December 2016, 103 patients with maximum diameters of ASD of less than 30 mm were allocated to groups taking either the percutaneous closure of atrial septal defects approach (PASD group, n = 53) or the intra-operative device closure approach (IODC Group, n = 50). They were operated on using the minimally invasive Amplatzer duct occluder under the guidance of transesophageal echocardiography without cardiopulmonary bypass. Echocardiography was performed to obtain an en face view of the ASD and important surrounding structures before the operation. Patient characteristics, perioperative data, and follow-up data were retrospectively documented and analyzed. RESULTS: Patient characteristics were comparable between the two groups. These were no differences in the maximum diameters of defects and the size of the occluders in each group (16.4 ± 5.3 mm vs16.4 ± 5.2 mm, P = 0.98; 22.4 ± 5.8 mm vs 21.3 ± 6.6 mm, P = 0.38). Intracardiac manipulation time was 20.72 ± 7.70 min in the PASD group and 6.01 ± 1.03 min in the IODC group (P < 0.001). The procedure time was 28.70 ± 10.41 min in the PASD group and 39.13 ± 6.03 min in the IODC group (P < 0.001). The successful closure defect was 100% in both groups when the maximum diameter of defect less than 25 mm. Four patients the PASD groups with maximum diameters between 25 mm and 30 mm were transferred to the IOCD group after unsuccessful device implantations. The total occlusion rate was 82% immediately after deployment, 98% at 3 months, and 100% at 6 months. No cardiac-related complications occurred during the follow-up period of between 3 to 65 months (mean 21.4 ± 9.8 months). CONCLUSIONS: Percutaneous device closures of Secundum atrial septal defects showed safety and high efficiency in patients under guidance by transesophageal echocardiography when compared with intra-operative device closures and are especially suited for women and children.

12.
J Cardiothorac Surg ; 15(1): 24, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31952521

RESUMO

BACKGROUND: Evaluate the safety and efficacy of our modified technique of the extravascular procedure for treating mild to moderately dilated ascending aorta in patients with bicuspid aortic valve (BAV) aortopathy. METHODS: From January 2015 to December 2018,119 consecutive patients with BAV and ascending aorta dilatation (dimension 40 mm~ 45 mm) were diagnosed in our institution. Among these,49 patients received aggressive aortic valve replace (AVR) + ascending aorta wrapped (wrapped group) while the other 70 patients received AVR + ascending aorta replacement (wheat group). All patients clinical and follow up data were collected for 12 months. RESULTS: Aortic clamping and cardio-pulmonary bypass times were significantly longer in wheat group than wrap group (P < 0.001and 0.021,respectively). The first 24 h drainage in wheat group were much more than wrap group(P = 0.04). Ascending aorta diameter、left ventricular end diameter and ejection fraction were statistically different between pre- and post-operation (p < 0.001) in both groups, but the heart function and complication were no difference during follow up. CONCLUSIONS: External wrapping of the ascending aorta and wheat procedure have good short-term and long-term results in BAV patients with a mild to moderately dilated ascending aorta. The perioperative period results of external wrapping of the ascending aorta for BAV patients were encouraging.

13.
Sci Signal ; 13(613)2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31911435

RESUMO

Mutations in WASHC5 (also known as KIAA0196) cause autosomal dominant hereditary spastic paraplegia (HSP) type SPG8. WASHC5, commonly called strumpellin, is a core component of the Wiskott-Aldrich syndrome protein and SCAR homolog (WASH) complex that activates actin nucleation at endosomes. Although various other cellular roles for strumpellin have also been described, none account for how SPG8-associated mutations lead to HSP. Here, we identified protein interactors of the WASH complex by immunoprecipitation and mass spectrometry and assessed the functions of strumpellin in cultured cells using both overexpression and RNA interference along with cell-spreading assays to investigate cell adhesion. We uncovered a decrease in CAV1 protein abundance as well as endosomal fission defects resulting from pathogenic SPG8 mutations. CAV1, a key component of caveolae, interacted with strumpellin in cells, and strumpellin inhibited the lysosomal degradation of CAV1. SPG8-associated missense mutations in strumpellin did not rescue endosomal tubulation defects, reduction in CAV1 protein abundance, or integrin-mediated cell adhesion in strumpellin-deficient cells. Mechanistically, we demonstrated that the WASH complex maintained CAV1 and integrin protein amounts by inhibiting their lysosomal degradation through its endosomal actin nucleation activity. In addition, the interaction of strumpellin with CAV1 stimulated integrin recycling, thereby promoting cell adhesion. These findings provide a molecular link between WASHC5 mutations and impairment of CAV1- and integrin-mediated cell adhesion, providing insights into the cellular pathogenesis of SPG8.

14.
Chemosphere ; 246: 125721, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31911326

RESUMO

Thallium (Tl), a ubiquitous environmental toxicant, can cross the placental barrier during pregnancy. However, the effects of prenatal Tl exposure on placental function are currently unclear. Based on the Ma'anshan Birth Cohort study, we examined whether long-term prenatal Tl exposure was associated with placental inflammation. Tl concentrations were quantified in serum samples (n = 7050) from 2515 pregnancy during each trimester, placental inflammatory cytokine mRNA expression was assessed in 2519 placenta tissues. Geometric mean values of serum Tl concentrations were 63.57, 63.63 and 48.71 ng/L for the first, second and third trimesters, respectively. After adjustment for potential confounders, serum Tl concentration was positively associated with CD68 (ß: 0.30; 95% CI: 0.05, 0.56) in the first trimester and TNF-α (ß: 0.12; 95% CI: 0.01, 0.23), IL-6 (ß: 0.15; 95% CI: 0.05, 0.25) and CD68 (ß: 0.25; 95% CI: 0.10, 0.39) in the third trimester, however was negatively associated with IL-4 (ß: -0.21; 95% CI: -0.41, -0.01) and CD206 (ß: -0.23; 95% CI: -0.45, -0.02) in the first trimester. Repeated measures analysis showed that TNF-α, IL-6 and CD68 increased by 0.11 (95% CI: 0.01, 0.21), 0.12 (0.15, 95% CI: 0.05, 0.25), 0.22 (95% CI: 0.10, 0.39), respectively, with each 1ln-transformed Tl increase in total samples. Gender-specific analyses revealed that these associations were largely driven by male offspring. In addition, immunohistochemistry revealed that nuclear NF-κB p65 expression increased in placenta tissue. The results of this prospective cohort study provide longitudinal evidence that prenatal Tl exposure induces a placental inflammatory response in the Chinese population.

15.
J Struct Biol ; 209(1): 107415, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31726097

RESUMO

The 2-carboxy-6-hydroxyoctahydroindole (Choi) moiety is an essential residue for the antithrombotic activities of aeruginosins, which are a class of cyanobacterial derived bioactive linear tetrapeptides. Biosynthetic pathway of Choi is still elusive. AerF was suggested to be involved in the biosynthesis of Choi, and can be assigned to the short-chain dehydrogenase/reductase (SDR) superfamily. However, both the exact role and the catalytic mechanism of AerF have not been elucidated. In this study, functional and mechanistic analyses of AerF from Microcystis aeruginosa were performed. Observation of enzymatic assay demonstrates that AerF is a NADPH-dependent alkenal double bond reductase that catalyzes the reduction of dihydro-4-hydroxyphenylpyruvate (H2HPP) to generate tetrahydro-4-hydroxyphenylpyruvate (H4HPP), which is the third step of the biosynthetic pathway from prephenate to Choi. Comparative structural analysis indicates that ligand binding-induced conformational change of AerF is different from that of the other SDR superfamily reductase using H2HPP as a substrate. Analyses of NADPH and substrate analogue binding sites combined with the results of mutagenesis analyses suggest that a particular serine residue mainly involves in the initiation of the proton transfer between the substrate and the residues of AerF, which is an uncommon feature in SDR superfamily reductase. Furthermore, based on the observations of structural and mutagenesis analyses, the catalytic mechanism of AerF is proposed and a proton transfer pathway in AerF is deduced.

16.
Am J Clin Nutr ; 111(1): 122-130, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31625576

RESUMO

BACKGROUND: Previous studies have shown conflicting findings regarding the relation of vitamin D status and supplementation during pregnancy with gestational diabetes mellitus (GDM). Most of these studies hypothesized that 25-hydroxyvitamin D [25(OH)D] concentrations were associated with GDM risk and glucose metabolism based on linear association models. OBJECTIVES: We aimed to estimate the associations of 25(OH)D concentrations and vitamin D supplementation with GDM risk and glucose metabolism and determine the threshold concentrations of 25(OH)D that could significantly affect glucose metabolism and GDM risk. METHODS: In a prospective birth cohort study, we collected information about sociodemographic characteristics, health status, and lifestyle from 4984 pregnant women. Vitamin D supplementation and 25(OH)D concentrations were assessed in the second trimester. Data from the 75-g oral-glucose-tolerance test were obtained at 24-28 weeks of gestation. RESULTS: A total of 922 (18.5%) women were diagnosed with GDM. Compared with women with 25(OH)D concentrations <25 nmol/L, the GDM risk was significantly lower in women with 25(OH)D concentrations ranging from 50 to 75 nmol/L (RR: 0.74; 95% CI: 0.58, 0.95) and >75 nmol/L (RR: 0.40; 95% CI: 0.22, 0.70). The curve-fitting models suggested a significant large reduction in GDM risk, fasting plasma glucose, and area under the curve of glucose with increasing 25(OH)D concentrations only for concentrations >50 nmol/L. Consistently, GDM risk was significantly reduced only in women who took 400-600 IU vitamin D/d (RR: 0.83; 95% CI: 0.70, 0.97) with a mean 25(OH)D concentration of 50 nmol/L but not in women taking vitamin D sometimes with a mean 25(OH)D concentration of 40 nmol/L. CONCLUSIONS: GDM risk was significantly reduced only in pregnant women with 25(OH)D concentrations >50 nmol/L. Pregnant women taking 400-600 IU vitamin D/d with mean 25(OH)D concentrations of 50 nmol/L had a lower risk of GDM.

17.
J Microbiol Methods ; 168: 105801, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31811904

RESUMO

The species Karenia mikimotoi is a common nearshore red tide alga that can secrete hemolytic exotoxin and ichthyotoxin, which can induce the death of fish and shellfish, causing severe economic losses. In this study, loop-mediated isothermal amplification (LAMP) was employed in combination with the lateral flow dipstick (LFD) visual detection method to establish the LAMP-LFD rapid detection method for K. mikimotoi. The internal transcribed spacer ITS1-5.8S-ITS2 of K. mikimotoi was used as the target sequence and was amplified with specific primers designed in this study. The results indicated that the amplification optimal reaction conditions for LAMP in this paper were for 20 min at 65 °C. Moreover, LAMP had excellent specificity, showing negative results for other common red tide causing algal species. In field samples, we successfully reduced the total time, with only 23 min needed from LAMP amplification to LFD result display, which was shorter than that of conventional PCR. Consequently, LAMP-LFD should be useful for rapid field detection of low-density K. mikimotoi and for the early prevention of red tide induced by such algae.

18.
Sci Total Environ ; 709: 135951, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-31887501

RESUMO

Shifts in bacterioplankton communities during algal blooms have been widely investigated, but our understanding of their succession over the continuous course of paralytic shellfish poisoning producing Gymnodinium catenatum blooms and diatom (Skeletonema costatum and Chaetoceros curvisetus) blooms in natural bays is highly understudied. Here, we used high-throughput sequencing of bacterioplankton 16S rRNA genes to investigate the composition and successional patterns of bacterioplankton communities during Gymnodinium-diatom bloom cycles. Changes in community compositional patterns were then evaluated in context of environmental and phytoplankton community variation. Bacterioplankton α-diversity significantly decreased during the emergence of the algal blooms, with Flavobacteriaceae, Rhodobacteraceae, Cryomorphaceae, and Saprospiraceae as the dominant bacterial families in waters during the blooms. Bacterioplankton community compositions could be separated into three successive stages according to bloom dynamics, wherein the succession of bacterioplankton communities was correlated with changes in algal species. Environmental variables, and particularly pH, salinity, and nutrient concentrations (e.g., of nitrite, nitrate, and ammonium) were strongly associated with variation in bacterioplankton community structures. Variance partitioning analysis indicated that phytoplankton effects alone could explain more variance than only environmental effects. Moreover, LEfSe analysis was used to identify special bacterioplankton genera as "biomarkers" for bloom stages, such as Tepidisphaera and Pseudarcicella, whose abundances were significantly associated with different stages of the phytoplankton blooms. The phylotype "biomarkers" that were identified hold significant potential as indicators for phytoplankton bloom successional dynamics. Overall, these results may contribute to the understanding of the ecological processes shaping microbial communities during successive Gymnodinium-diatom blooms.


Assuntos
Dinoflagelados , Diatomáceas , Eutrofização , Fitoplâncton , RNA Ribossômico 16S
19.
Neurosci Lett ; 714: 134546, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31629775

RESUMO

The effect of situational hazardous level on pedestrian hazard perception was investigated using event-related potential (ERP) technique. Images of three types of real traffic situations were used as test materials, including non-hazard situations, low-hazard situations and high-hazard situations. The existence of hazard in situations shown in the images was determined by 29 students (including 16 female) via button pushing. The results showed that the N1 amplitude was higher in high-hazard situations than in non-hazard or low-hazard situations; and the P3 amplitude was higher in low-hazard situations than in non-hazard or high-hazard situations. These results indicated that the high-hazard situations have a processing advantage in early processing stages, while low-hazard situations have a processing advantage in late processing stages.

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