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1.
Arch Gynecol Obstet ; 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34820720

RESUMO

BACKGROUND: The study aimed to investigate the potential risk factors for the placenta accreta spectrum (PAS), determine the predictive value of a diagnostic model, and evaluate the effects of octamethylcyclotetrasiloxane (OMCTS) on trophoblast proliferation and migration. METHODS: This case-control study included 244 pregnant women with PAS and 327 normal pregnant women who visited Guangzhou Women and Children's Medical Centre, China, from January 2014 to December 2017. Blood was collected from 42 women with PAS and 77 controls, and plasma specimens were analyzed by gas chromatography-time-of-flight mass spectrometry. In addition, the proliferation and migration of trophoblast cells were examined after treatment with OMCTS. RESULTS: We found an association between the risk of PAS and clinical factors related to fasting blood glucose levels (BS0, OR = 5.78), as well as factors related to endometrial injury [history of cesarean section (OR = 179.59), uterine scarring (OR = 68.37), and history of abortion (OR = 5.66)]. Equally important, pregnant women with PAS had significantly higher plasma OMCTS concentrations than controls. In vitro, we found that OMCTS could promote the proliferation and migration of HTR8/SVneo cells. The model of combining clinical factors and OMCTS had a good performance in PAS prediction (AUC = 0.97, 95% CI 0.78-0.93). CONCLUSIONS: The early diagnosis of PAS in pregnant women requires assessing risk factors, metabolic status, and BS0 levels before 20 weeks of gestation. OMCTS may be related to the development of PAS by promoting trophoblast cell proliferation and migration.

2.
BMC Plant Biol ; 21(1): 546, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34800972

RESUMO

BACKGROUND: NAC (NAM, ATAF and CUC) transcription factors (TFs) play vital roles in plant development and abiotic stress tolerance. Salt stress is one of the most limiting factors for rice growth and production. However, the mechanism underlying salt tolerance in rice is still poorly understood. RESULTS: In this study, we functionally characterized a rice NAC TF OsNAC3 for its involvement in ABA response and salt tolerance. ABA and NaCl treatment induced OsNAC3 expression in roots. Immunostaining showed that OsNAC3 was localized in all root cells. OsNAC3 knockout decreased rice plants' sensitivity to ABA but increased salt stress sensitivity, while OsNAC3 overexpression showed an opposite effect. Loss of OsNAC3 also induced Na+ accumulation in the shoots. Furthermore, qRT-PCR and transcriptomic analysis were performed to identify the key OsNAC3 regulated genes related to ABA response and salt tolerance, such as OsHKT1;4, OsHKT1;5, OsLEA3-1, OsPM-1, OsPP2C68, and OsRAB-21. CONCLUSIONS: This study shows that rice OsNAC3 is an important regulatory factor in ABA signal response and salt tolerance.

3.
Biochem Biophys Res Commun ; 583: 128-134, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34735874

RESUMO

Preeclampsia (PE) threatens the safety of mothers and fetuses, and its pathogenesis is still unclear. Our previous study has found the relationship between PE and serum Clusterin (CLU). This study aimed to investigate the role of CLU on PE. Firstly, levels of CLU in serum and placental tissue from PE patients and healthy pregnancies were compared. Then, RNA sequencing, cell counting kit-8, matrigel invasion, cell apoptosis, and angiogenesis assay were performed to evaluate the role of CLU on primary isolation trophoblast cells. We found the expression of CLU was increased before the clinical syndrome occurred, whereas its level was positively related to the severity of PE. CLU significantly inhibited the expression of matrix metalloproteinase-9 and Vimentin and enhanced E-cadherin to inhibit epithelial-mesenchymal transition of trophoblast cells, further reducing its migration and invasion. Our results suggested that CLU may play a role in regulating trophoblast invasion and migration during placental development, which may be one of the risk factors for PE.

4.
J Dent ; 116: 103888, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34762990

RESUMO

OBJECTIVES: The humid oral environment adversely affects the interaction between a functionalised primer and dentine collagen after acid-etching. Robust adhesion of marine mussels to their wet substrates instigates the quest for a strategy that improves the longevity of resin-dentine bonds. In the present study, an etching strategy based on the incorporation of biomimetic dopamine methacrylamide (DMA) as a functionalised primer into phosphoric acid etchant was developed. The mechanism and effect of this DMA-containing acid-etching strategy on bond durability were examined. METHODS: Etchants with different concentrations of DMA (1, 3 or 5 mM) were formulated and tested for their demineralisation efficacy. The interaction between DMA and dentine collagen, the effect of DMA on collagen stability and the collagenase inhibition capacity of the DMA-containing etchants were evaluated. The effectiveness of this new etching strategy on resin-dentine bond durability was investigated. RESULTS: All etchants were capable of demineralising dentine and exposing the collagen matrix. The latter strongly integrated with DMA via covalent bond, hydrogen bond and Van der Waals' forces. These interactions significantly improve collagen stability and inhibited collagenase activity. Application of the etchant containing 5 mM DMA achieved the most durable bonding interface. CONCLUSION: Dopamine methacrylamide interacts with dentine collagen in a humid environment and improves collagen stability. The monomer effectively inactivates collagenase activity. Acid-etching with 5 mM DMA-containing phosphoric acid has the potential to prolong the longevity of bonded dental restorations without compromising clinical operation time. CLINICAL SIGNIFICANCE: The use of 5 mM dopamine methacrylamide-containing phosphoric acid for etching dentine does not require an additional clinical step and has potential to improve the adhesive performance of bonded dental restorations.

5.
Ann Transl Med ; 9(18): 1471, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34734023

RESUMO

Background: Cognitive impairment is a serious complication of diabetes that manifests as an impairment of spatial memory and learning ability. Its pathogenesis is unclear, and effective therapeutic drugs are very limited. Our group designed and synthesized a novel compound named 3-p-tolyl-9H-xanthen-9-one (Tozan). In this study, we sought to investigate the effects and mechanism of Tozan on diabetic cognitive impairment. Methods: Methylglyoxal (MG)-induced SH-SY5Y cells and streptozotocin (STZ)-induced type 1 diabetic mice were treated with Tozan. Methyl thiazolul tetrazolium (MTT) and lactate dehydrogenase (LDH) were used to test cytotoxicity. Morris water maze (MWM) and Y-maze tests were used to evaluate cognitive function. Immunofluorescence and western blot analyses were used to evaluate neurogenesis, apoptosis, and signal transduction pathway-related proteins. In addition, Lentivirus (LV)-estrogen receptor beta (ERß)-ribonucleic acid interference (RNAi) was used to knockdown the ERß gene in SH-SY5Y cells. Results: We found that Tozan ameliorated MG-induced cytotoxicity in SH-SY5Y cells, improved cognitive dysfunction in STZ-induced type 1 diabetic mice, increased neurogenesis, and prevented apoptotic responses in vitro and in vivo. Importantly, Tozan (2, 4, and 8 mg/kg) mediated phosphatidylinositol-3-kinase and protein kinase B cAMP-response element binding protein (PI3K/Akt-CREB) signaling by activating membrane ERß, and a high dose of Tozan (8 mg/kg) mediated CREB signaling by activating nuclear ERß in the hippocampus. Notably, Tozan did not have an anti-apoptosis and regeneration protective role in ERß gene knockdown cells. Conclusions: Our study demonstrates Tozan's contributions to and role in cognition, neurogenesis, and apoptosis in diabetes, and lays an experimental foundation for the development of new anti-diabetic cognitive impairment drugs.

6.
Ann Transl Med ; 9(20): 1531, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34790737

RESUMO

Background: Our previous studies demonstrated that cysteinyl leukotrienes receptor 1 (CysLT1R) knockout, pharmacological blockade, or hippocampus knockdown produced beneficial effects against Alzheimer's disease (AD); however, whether CysLT1R upregulation has deleterious effects on AD remains elusive. Methods: In this study, we investigated the changes in behaviors, hippocampal amyloidogenesis, and synapse plasticity after CysLT1R overexpression by microinfusion of the lentiviral vector, containing its coding sequence of mouse (LV-CysLT1R), into the bilateral dentate gyri (DG) of the hippocampus or CysLT1R activation by repeated systemic administration of its agonist YM-17690 (0.1 mg/kg, once a day, i.p., for 28 d). Results: The behavior data showed that overexpression of CysLT1R in hippocampal DG or administration of YM-17690 deteriorated behavioral performance in Morris water maze (MWM), Y-maze tests, and novel object recognition (NOR) in young APP/PS1 mice. The further studies showed that these treatments significantly destroyed synaptic function, as evidenced by impaired hippocampal long-term potentiation (LTP), decreased spine density, low number of synapses, and decreased postsynaptic protein (PSD95), and promoted the generation of amyloid ß (Aß) through increased expression of BACE1 and PS1 in the hippocampus of young APP/PS1 mice. Conclusions: Together, our results indicate that CysLT1R upregulation accelerates memory impairment in young APP/PS1 mice, which is associated with promoting synaptic dysfunction and amyloidogenesis in the hippocampus.

7.
J Exp Clin Cancer Res ; 40(1): 342, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34706749

RESUMO

BACKGROUND: Although thousands of long noncoding RNAs (lncRNAs) have been annotated, only a few lncRNAs have been characterized functionally. In this study, we aimed to identify novel lncRNAs involved in the progression of gastric carcinoma (GC) and explore their regulatory mechanisms and clinical significance in GC. METHODS: A lncRNA expression microarray was used to identify differential lncRNA expression profiles between paired GCs and adjacent normal mucosal tissues. Using the above method, the lncRNA SGO1-AS1 was selected for further study. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and in situ hybridization (ISH) were performed to detect SGO1-AS1 expression in GC tissues. Gain-of-function and loss-of-function analyses were performed to investigate the functions of SGO1-AS1 and its upstream and downstream regulatory mechanisms in vitro and in vivo. RESULTS: SGO1-AS1 was downregulated in gastric carcinoma tissues compared to adjacent normal tissues, and its downregulation was positively correlated with advanced clinical stage, metastasis status and poor patient prognosis. The functional experiments revealed that SGO1-AS1 inhibited GC cell invasion and metastasis in vitro and in vivo. Mechanistically, SGO1-AS1 facilitated TGFB1/2 mRNA decay by competitively binding the PTBP1 protein, resulting in reduced TGFß production and, thus, preventing the epithelial-to-mesenchymal transition (EMT) and metastasis. In addition, in turn, TGFß inhibited SGO1-AS1 transcription by inducing ZEB1. Thus, SGO1-AS1 and TGFß form a double-negative feedback loop via ZEB1 to regulate the EMT and metastasis. CONCLUSIONS: SGO1-AS1 functions as an endogenous inhibitor of the TGFß pathway and suppresses gastric carcinoma metastasis, indicating a novel potential target for GC treatment.

8.
J Cell Mol Med ; 25(22): 10698-10710, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34708522

RESUMO

We examined the mechanism by which lithium chloride (LiCl) attenuates the impaired learning capability and memory function of dual-transgenic APP/PS1 mice. Six- or 12-month-old APP/PS1 and wild-type (WT) mice were randomized into four groups, namely WT, WT+Li (100 mg LiCl/kg body weight, gavage once daily), APP/PS1 and APP/PS1+Li. Primary rat hippocampal neurons were exposed to ß-amyloid peptide oligomers (AßOs), LiCl and/or XAV939 (inhibitor of Wnt/ß-catenin) or transfected with small interfering RNA against the ß-catenin gene. In the cerebral zone of APP/PS1 mice, the level of Aß was increased and those of α7 nicotinic acetylcholine receptors (nAChR), phosphor-GSK3ß (ser9), ß-catenin and cyclin D1 (protein and/or mRNA levels) reduced. Two-month treatment with LiCl at ages of 4 or 10 months weakened all of these effects. Similar expression variations were observed for these proteins in primary neurons exposed to AßOs, and these effects were attenuated by LiCl and aggravated by XAV939. Inhibition of ß-catenin expression lowered the level of α7 nAChR protein in these cells. LiCl attenuates the impaired learning capability and memory function of APP/PS1 mice via a mechanism that might involve elevation of the level of α7 nAChR as a result of altered Wnt/ß-catenin signalling.

9.
Lab Chip ; 21(22): 4390-4400, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34704106

RESUMO

In the chemical and biological fields, the creation of concentration gradient microenvironments is an important approach for many applications, such as crystal growth and drug screening. Although many concentration gradient generators have been demonstrated, current generators can hardly produce ultra-long linear concentration gradients. In this paper, we propose a concentration-gradient flow/droplet generator which consists of a microfluidic flow switch, a cavity array for stage-by-stage concentration dilution, and an optional T-junction for droplet formation. The generator can realize an ultra-long continuously-varying concentration gradient along the flow direction. Generation of a 38 mm concentration gradient was demonstrated. The length can be further extended by enlarging the capacity of the cavities and increasing the number of the stages. The concentration gradient showed high linearity in the range of 10% to 90%. Moreover, cyclic generation of a concentration gradient flow and droplets with different concentrations was realized by the generator. In a demonstration of drug screening, the generator was employed to produce paclitaxel in different concentrations. A negative correlation between the 4T1 cell viability and the paclitaxel concentration was observed after the treatment. We envision that the concentration gradient generator will be a promising candidate for various drug screening applications.


Assuntos
Microfluídica
10.
Cell Death Discov ; 7(1): 236, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34493714

RESUMO

As a common chronic metabolic disease, the development of diabetes mellitus (DM) may also be accompanied by liver damage and inflammatory disorders. Sitagliptin is an inhibitor of dipeptidyl peptidase-4 (DPP4, also known as CD26), which is clinically used for DM treatment. However, the mechanism of sitagliptin's efficiency in liver diseases is largely unknown. In this study, mice suffering from streptozotocin (STZ) exhibit elevated liver DPP4 expression and activity, as well as inflammatory and chronic liver injury phenotype, whereas specifically inhibiting the activity of DPP4 in mouse liver tissues and hepatocytes by sitagliptin contributes to decreased cytokines, oxidative stress, cell apoptosis, and inflammation in STZ-induced diabetic mice. Moreover, sitagliptin reduced TNFα or LPS-induced cellular reactive oxygen species (ROS) level, cell apoptosis, and protein expression in the NFκB signaling pathway in HepG2 cells or primary mouse hepatocytes. Altogether, our study confirms that sitagliptin may protect liver tissue by alleviating ROS production and NFκB signaling activation, providing a putative mechanism for preventing the development of diabetic liver disease.

11.
Toxicol Appl Pharmacol ; 431: 115731, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34592322

RESUMO

Benzethonium chloride (BZT) and domiphen bromide (DMP) are widely used as antimicrobials in drugs, vaccines and industry. However, no cardiac safety data has been developed on both compounds. Previously we reported BZT and DMP as high-affinity human ether-a-go-go related gene (HERG) channel inhibitors with unknown proarrhythmic risk. Here, we investigate the cardiotoxicity of BZT and DMP in vitro and in vivo, aiming to improve the safety-in-use of both antimicrobials. In the present study, human iPSC derived cardiomyocytes (hiPSC-CMs) were generated and rabbit models were used to examine the proarrhythmic potential of BZT and DMP. Our results found that BZT and DMP induced time- and dose-dependent decrease in the contractile parameters of hiPSC-CMs, prolonged FPDc (≥ 0.1 µM), caused tachycardia/fibrillation-like oscillation (0.3-1 µM), ultimately progressing to irreversible arrest of beating (≥ 1 µM). The IC50 values of BZT and DMP derived from normalized beat rate were 0.13 µM and 0.10 µM on hiPSC-CMs at 76 days. Moreover, in vivo rabbit ECG data demonstrated that 12.85 mg/kg BZT and 3.85 mg/kg DMP evoked QTc prolongation, noncomplex arrhythmias and ventricular tachycardias. Our findings support the cardiac safety of 0.01 µM BZT/DMP in vitro and the intravenous infusion of 3.85 mg/kg BZT and 1.28 mg/kg DMP in vivo, whereas higher concentrations of both compounds cause mild to moderate cardiotoxicity that should not be neglected during medical and industrial applications.

12.
Angew Chem Int Ed Engl ; 60(48): 25241-25245, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34550636

RESUMO

Atomically dispersed transition metal sites have been extensively studied for CO2 electroreduction reaction (CO2 RR) to CO due to their robust CO2 activation ability. However, the strong hybridization between directionally localized d orbits and CO vastly limits CO desorption and thus the activities of atomically dispersed transition metal sites. In contrast, s-block metal sites possess nondirectionally delocalized 3s orbits and hence weak CO adsorption ability, providing a promising way to solve the suffered CO desorption issue. Herein, we constructed atomically dispersed magnesium atoms embedded in graphitic carbon nitride (Mg-C3 N4 ) through a facile heat treatment for CO2 RR. Theoretical calculations show that the CO desorption on Mg sites is easier than that on Fe and Co sites. This theoretical prediction is demonstrated by experimental CO temperature program desorption and in situ attenuated total reflection infrared spectroscopy. As a result, Mg-C3 N4 exhibits a high turnover frequency of ≈18 000 per hour in H-cell and a large current density of -300 mA cm-2 in flow cell, under a high CO Faradaic efficiency ≥90 % in KHCO3 electrolyte. This work sheds a new light on s-block metal sites for efficient CO2 RR to CO.

13.
Life Sci ; 285: 119991, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34592230

RESUMO

AIM: Elevated Treg is relevant to persistent HBV infection, and the regulatory mechanism of Treg levels remains unclear. E proteins are important transcriptional regulators and could be antagonized by inhibitors of DNA-binding (Id) 1-4. We aim to clarify the role of Ids during HBV infection. MAIN METHODS: Changes of Ids and their relationship with Treg were investigated in both HBV transfection model and hepatitis B patients. Significance of Ids was studied by in vitro Treg differentiation induction with Id inhibited or over-expressed. The role of inflammatory cytokines for Id was studied by co-culture. RNA-Seq was conducted to explore the differentially expressed genes in Id-overexpressed CD4 T cells upon Treg differentiation induction conditions. KEY FINDINGS: Id-overexpressed mice attenuated virus clearance in HBV transfection model. In the HBV transfection mouse model, Tregs were up-regulated, with Id3 increased in Treg as well. Clinically, circulating Tregs in chronic hepatitis B (CHB) patients were elevated, and elevated Id3 transcriptional levels were positively correlated with Tregs. IL-1ß could up-regulate Id3 in Treg cells induced in vitro. RNA-Seq revealed that increased Id could cause a series of signaling pathway changes during Treg differentiation. SIGNIFICANCE: Id3 is elevated during HBV infection to ease Treg differentiation, and the antiviral immunity is influenced that make the infection to develop into chronic state.


Assuntos
Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Proteínas Inibidoras de Diferenciação/metabolismo , Proteínas de Neoplasias/metabolismo , Linfócitos T Reguladores/imunologia , Adulto , Animais , Diferenciação Celular , Feminino , Regulação da Expressão Gênica , Humanos , Proteínas Inibidoras de Diferenciação/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , RNA-Seq , Regulação para Cima
15.
Stem Cells Int ; 2021: 9919422, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34434242

RESUMO

Widely known for self-renewal and multilineage differentiation, stem cells can be differentiated into all specialized tissues and cells in the body. In the past few years, a number of researchers have focused on deriving hematopoietic stem cells (HSCs) from pluripotent stem cells (PSCs) as alternative sources for clinic. Existing findings demonstrated that it is feasible to obtain HSCs and certain mature blood lineages from PSCs, except for several issues to be addressed. This short review outlines the technologies used for hematopoietic differentiation in recent years. In addition, the therapeutic value of PSCs as a potential source of various blood cells is also discussed as well as its challenges and directions in future clinical applications.

16.
Front Med (Lausanne) ; 8: 701494, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34447764

RESUMO

Methicillin-susceptible (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) nasal colonization predisposes individuals for endogenous infections and is a major threat to children. Recently, oxacillin/cefoxitin-susceptible mecA-positive S. aureus (OS-MRSA) has been reported worldwide. Herein, a prospective, cross-sectional study was conducted across five schools, representing three educational stages, in Guangzhou, China. Nasal swabs from 2,375 students were cultured for S. aureus and all isolates were subjected to antibiotic susceptibility testing phenotypically and confirmed by femB and mecA genetic detection; all the isolates were classified as MSSA, MRSA, or OS-MRSA. All strains were also analyzed by multi-locus sequence typing. Among the 2,375 swabs, S. aureus was detected in 744 children (31.3%, 95% CI: 25.9-36.7%), of whom 72 had MRSA (3.0%, 95% CI: 0.6-5.4%) and 4 had OS-MRSA (0.2%, 95% CI: 0.1-0.3%), of which an oxacillin- and cefoxitin-susceptible MRSA strain was identified. The prevalence of S. aureus and MRSA was higher in younger children. The highest percentage of drug resistance of the S. aureus isolates (n = 744) was to penicillin (85.5%), followed by erythromycin (43.3%) and clidamycin (41.0%). The most prevalent sequence types (STs) were ST30, ST45, and ST188 in MSSA, accounting for 38.7% of the total isolates, whereas ST45, ST59, and ST338 accounted for 74.6% of the MRSA isolates and ST338 accounted for 50.0% of the OS-MRSA isolates. The MRSA and OS-MRSA isolates (n = 76) were grouped into three clades and one singleton, with clonal complex (CC) 45 as the most predominant linkage. The top nine multi-locus sequence typing-based CCs (CC30, CC45, CC5, CC1, CC15, CC944, CC398, CC59, CC7) represented 86.7% of all S. aureus isolates. All CC30 isolates were resistant to erythromycin and clidamycin, and almost all these isolates were also resistant to penicillin (99.2%). The CC45 and CC59 isolates exhibited high resistance rates to oxacillin at 31.5 and 59.0%, respectively. This study provides updated data valuable for designing effective control strategies to mitigate the burden of disease and to improve the adequacy of empirical antimicrobial treatments for potentially harmful infections.

17.
J Antibiot (Tokyo) ; 74(11): 821-824, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34408287

RESUMO

One new benzophenone derivative, named penibenzophenone C (1), and a new benzophenone natural product, neamed penibenzophenone D (2), together with two known compounds (3, 4) were isolated from the EtOAc extract of the endophytic fungus Penicillium sp. isolated from the mangrove Acanthus ilicifolius L. collected in the South China Sea. The structures of 1-4 were elucidated by extensive NMR spectral interpretation and MS data. The new compounds 1 and 2 showed moderate antibacterial activities against methicillin-resistant Staphylococcus aureus with the MIC values of 3.12 and 6.25 µg ml-1, respectively.

18.
ChemSusChem ; 14(18): 3959-3966, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34323014

RESUMO

Developing low-cost but efficient electrocatalysts to promote the sluggish kinetics of oxygen evolution from water splitting is essential for hydrogen production. In this study, a hierarchical hollow hydrangea-like CoRu/Co superstructure is constructed through a self-templating method by morphology-controlled pyrolysis of flower-like Ru-doped Co-based layered double hydroxides (LDH). The anchoring of Ru into Co-LDH is the key to the formation of well-defined hydrangea-like three-dimensional superstructure composed of CoRu/Co. The optimized CoRu/Co-M-350 with a low Ru loading of 3.0 wt% exhibits excellent catalytic performances in the oxygen evolution reaction (OER) with low overpotential (η10 =192 mV) and excellent stability for 100 h at 100 mA cm-2 in alkaline media, outperforming the benchmark RuO2 and most reported electrocatalysts. The superior morphology and structural features of CoRu/Co-M-350 provide not only abundant accessible surface sites but also fast mass and electron transfer, thereby promoting OER catalysis. The present study provides a new synthetic route for preparing highly active OER electrocatalysts.

19.
Clin Exp Immunol ; 206(2): 141-152, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34309827

RESUMO

Primary anti-phospholipid antibody syndrome (pAPS) is a multi-organ autoimmune disease, and autoantibodies are involved in its pathogenesis. Follicular helper T cells (Tfh) and follicular regulatory T cells (Tfr) are critical for B cell maturation and antibody production, but their roles in pAPS remain unknown. We enrolled 32 pAPS patients and 23 healthy controls (HCs) and comprehensively analyzed circulating Tfh and Tfr, as well as their subsets, using flow cytometry. Clinical data including autoantibody levels were collected and their correlations with Tfh and Tfr subsets were analyzed. In addition, correlation analyses between B cell functional subsets and Tfh and Tfr were performed. Changes and potential effects of serum cytokines on Tfr and Tfh were further explored. We found the circulating Tfr was significantly decreased while Tfh and Tfh/Tfr ratios were increased in pAPS patients. Tfh2, inducible T cell co-stimulator (ICOS)+  programmed cell death 1 (PD-1)+  Tfh and Ki-67+  Tfh percentages were elevated, while CD45RA- forkhead box protein 3 (FoxP3)hi , Helios+ , T cell immunoglobulin and ITIM (TIGIT)+  and Ki-67+  Tfr percentages were decreased in pAPS patients. New memory B cells and plasmablasts were increased and altered B cell subsets and serum autoantibodies were positively correlated with Tfh, Tfh2, ICOS+ PD-1+  Tfh cells and negatively associated with Tfr, CD45RA- FoxP3hi Tfr and Helios+  Tfr cells. In addition, pAPS with LA/aCL/ß2GPI autoantibodies showed lower functional Tfr subsets and higher activated Tfh subsets. Serum interleukin (IL)-4, IL-21, IL-12 and transforming growth factor (TGF)-ß1 were up-regulated and associated with Tfh and Tfr subset changes. Our study demonstrates that imbalance of circulating Tfr and Tfh, as well as their functional subsets, is associated with abnormal autoantibody levels in pAPS, which may contribute to the pathogenesis of pAPS.

20.
Infect Dis Poverty ; 10(1): 102, 2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34294157

RESUMO

BACKGROUND: Measles outbreaks re-emerged in 2013-2014 in Guangxi Zhuang Autonomous Region of China, where measles immunisation coverage is high. The discrepancy between the vaccination coverage and outbreaks indicates that timeliness is crucial, yet there is limited knowledge on the health system barriers to timely vaccination. Using integrated evidence at the household, village clinic, and township hospital levels, this study aimed to identify the determinants of failure in receiving timely measles vaccinations among children in rural Guangxi. METHODS: A multi-stage stratified cluster sampling survey with a nested qualitative study was conducted among children aged 18-54 months in Longan, Zhaoping, Wuxuan, and Longlin counties of Guangxi from June to August 2015. The status of timely vaccinations for the first dose of measles-containing vaccine (MCV1) and the second dose of measles-containing vaccine (MCV2) was verified via vaccination certificates. Data on household-level factors were collected using structured questionnaires, whereas data on village and township-level factors were obtained through in-depth interviews and focus group discussions. Determinants of untimely measles vaccinations were identified using multilevel logistic regression models. RESULTS: A total of 1216 target children at the household level, 120 villages, and 20 township hospitals were sampled. Children were more likely to have untimely vaccination when their primary guardian had poor vaccination knowledge [MCV1, odds ratio (OR) = 1.72; MCV2, OR = 1.51], had weak confidence in vaccines (MCV1, OR = 1.28-4.58; MCV2, OR = 1.42-3.12), had few practices towards vaccination (MCV1, OR = 12.5; MCV2, OR = 3.70), or had low satisfaction with vaccination service (MCV1, OR = 2.04; MCV2, OR = 2.08). This trend was also observed in children whose village doctor was not involved in routine vaccination service (MCV1, OR = 1.85; MCV2, OR = 2.11) or whose township hospital did not provide vaccination notices (MCV1, OR = 1.64; MCV2, OR = 2.05), vaccination appointment services (MCV1, OR = 2.96; MCV2, OR = 2.74), sufficient and uniformly distributed sessions for routine vaccination (MCV1, OR = 1.28; MCV2, OR = 1.17; MCV1, OR = 2.08), or vaccination service on local market days (MCV1, OR = 2.48). CONCLUSIONS: Guardians with poor knowledge, weak beliefs, and little practice towards vaccination; non-involvement of village doctors in routine vaccinations; and inconvenient vaccination services in township hospitals may affect timely measles vaccinations among children in rural China.


Assuntos
Vacina contra Sarampo , Sarampo , China/epidemiologia , Humanos , Programas de Imunização , Lactente , Sarampo/epidemiologia , Sarampo/prevenção & controle , Vacinação , Cobertura Vacinal
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