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1.
Chemphyschem ; 17(4): 481-8, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26774082

RESUMO

Graphitic carbon nitride (g-C3 N4 ), synthesised by pyrolysis of different precursors (dicyandiamide, melamine and urea) under varying reaction conditions (air and nitrogen gas) is subjected to electrochemical studies for the elucidation of the inherent catalytic efficiency of the pristine material. Contrary to popular belief, pristine g-C3 N4 shows negligible, if any, enhancement in its electrochemical behaviour in this comprehensive study. Voltammetric analysis reveals g-C3 N4 to display similar catalytic efficiency to the unmodified glassy carbon electrode surface on which the bulk material was deposited. This highlights the non-catalytic nature of the pristine material and challenges the feasibility of using g-C3 N4 as a heterogeneous catalyst to deliver numerous promised applications.

2.
J Environ Manage ; 151: 267-79, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25585140

RESUMO

Globally, much weight is currently being placed on agriculture to provide food for the growing population as well as feedstock for the bioenergy industry. Unfortunately, the intensification of agricultural operations to satisfy these growing needs has been associated with a number of environmental and human health risks. A review of publications on the subject was conducted and emphasis was placed on articles focusing on agriculture, environment, and public health as well as their interactions. Supporting information was also gathered from publications of various agricultural and environmental agencies. Agricultural practices with potential negative implications on the environment and human health were identified broadly as: (a) utilization of biosolids and animal manures, (b) use of agricultural chemicals, (c) management of post-harvest residue, (d) irrigation, and (e) tillage operations. Soil, water, and air contamination by nutrients, heavy metals, pathogens, and pesticides, as well as air contamination by particulate matters, noxious gases, and pathogens were among the leading environmental impacts. Some of the human-health impacts identified included neurological and reproductive defects, cardiovascular risks, cancers and other diseases (of kidney, liver, lung, and skin), skin allergies, gastroenteritis, and methemoglobinemia. Continual awareness on the impacts of the reviewed agricultural practices on environmental quality and human health and the implementation of experimentally-backed best management practices in agricultural systems remain indispensable.


Assuntos
Agricultura/métodos , Produtos Agrícolas , Meio Ambiente , Agricultura/normas , Animais , Monitoramento Ambiental , Indicadores Básicos de Saúde , Humanos , Metais Pesados/química , Praguicidas/química , Poluentes do Solo/química , Estados Unidos
3.
Andrology ; 12(6): 1336-1346, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38228861

RESUMO

PURPOSE: Teratozoospermia is the main pathogenic factor of male infertility. However, the genetic etiology of teratozoospermia is largely unknown. This study aims to clarify the relationship between novel variations in TENT5D and teratozoospermia in infertile patients. MATERIALS AND METHODS: Two infertile patients were enrolled. Routine semen analysis of patients and normal controls was conducted with the WHO guidelines. Whole-exome sequencing (WES) was conducted to identify pathogenic variants in the two patients. Morphology and ultrastructure analysis of spermatozoa in the two patients was determined by Papanicolaou staining, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The functional effect of the identified variants was analyzed by immunofluorescence staining and western blotting. The expression of TENT5D in different germ cells was detected by immunofluorescence staining. RESULTS: Two new hemizygous variations, c.101C > T (p.P34L) and c.125A > T (p.D42V), in TENT5D were detected in two patients with male infertility. Morphology analysis showed abnormalities in spermatozoa morphology in the two patients, including multiple heads, headless, multiple tails, coiled, and/or bent flagella. Ultrastructure analysis showed that most of the spermatozoa exhibited missing or irregularly arranged '9+2' structures. Further functional experiments confirmed the abrogated TENT5D protein expression in patients. In addition, both p.P34L and p.D42V substitutions resulted in a conformational change of the TENT5D protein. We precisely analyzed the subcellular localization of TENT5D in germ cells in humans and mice. And we found that TENT5D was predominantly detected in the head and flagellum of elongating spermatids and epididymal spermatozoa. CONCLUSIONS: Our results showed further evidence of a relationship between TENT5D mutation and human male infertility, providing new genetic insight for use in the diagnosis and treatment of male infertility.


Assuntos
Espermatozoides , Teratozoospermia , Humanos , Masculino , Teratozoospermia/genética , Espermatozoides/ultraestrutura , Espermatozoides/metabolismo , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Adulto , Sequenciamento do Exoma , Animais , Análise do Sêmen
4.
World J Clin Cases ; 11(24): 5678-5691, 2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37727711

RESUMO

BACKGROUND: Hypertension is a common chronic disease that affects many people worldwide. Only a few reports related to the exploration of relevant indicators of the prethrombotic state in patients with primary hypertension (PH) in clinical settings were available. AIM: To detect prethrombotic state-related indicators in patients with PH and analyze their differences in different patient populations to provide a laboratory basis for the clinical prevention and control of hypertensive thrombotic diseases. METHODS: The general data of patients with PH who attended the Department of Cardiovascular Medicine, The First Affiliated Hospital of Jiangxi Medical College, from January 2022 to December 2022 were collected retrospectively. The patients were divided into three groups of 40 patients each according to the Grade of PH: Grade 1, Grade 2, and Grade 3 hypertension experimental group. The baseline data of 40 volunteers, who underwent physical examination in our hospital but were not diagnosed with PH during the same period, were included in the control group. The relevant indicators of prethrombotic state of the participants were compared, and mainly included inflammation-related indicators, hemorheology-related indicators, and coagulation function related indicators. The relationship between the aforementioned indicators and the progression of PH was analyzed. RESULTS: No significant differences were observed in age, sex, diabetes mellitus, smoking history, drinking history, body mass index, New York Heart Association functional classification, or the course of hypertension among the four groups (P > 0.05). The expressions of high-sensitivity C-reactive protein (hs-CRP), thrombomodulin (TM), hematocrit (Hct), erythrocyte sedimentation rate (ESR), P-selectin on platelet surface (CD62P), and fibrinogen (FIB) in the control group were < Grade 1 hypertension group < Grade 2 hypertension group < Grade 3 hypertension group, and the expressions of platelet (PLT), activated partial thromboplastin time (APTT), prothrombin (PT), and plasma thrombin time (TT) in the control group was > Grade 1 hypertension group > Grade 2 hypertension group > Grade 3 hypertension group, and the difference was statistically significant (P < 0.05). The results of the multivariate logistic regression model showed that the expression of hs-CRP, TM, Hct, ESR, CD62P, PLT, APTT, PT, TT, and FIB in the included participants was related to the progression of PH. Among these, high expression of hs-CRP, TM, Hct, ESR, CD62P, APTT, PT, and TT, and low expression of PLT and FIB were risk factors for PH (OR > 1, P < 0.05). The results of the receiver operating characteristic curve analysis showed that the area under the curve of hs-CRP, TM, ESR, CD62P, APTT, PT, TT, and FIB for the prediction of PH were > 0.80, and the prediction value was ideal. Linear correlation analysis with bivariate Spearman showed that hs-CRP, TM, Hct, ESR, CD62P, APTT, PT, and TT were positively correlated with each other (r > 0, P < 0.05); PLT and FIB were negatively correlated with hs-CRP, TM, Hct, ESR, CD62P, APTT, PT, and TT (r < 0, P < 0.05); and PLT and FIB were positively correlated (r > 0, P < 0.05). Linear correlation analysis using bivariate Spearman showed that hs-CRP, TM, Hct, ESR, CD62P, and FIB were positively correlated with each other (r > 0, P < 0.05), whereas PLT, APTT, PT, and TT were negatively correlated with hs-CRP, TM, Hct, ESR, CD62P, and FIB (r < 0, P < 0.05). There was a positive correlation between PLT, APTT, PT, and TT (r > 0, P < 0.05). CONCLUSION: The relevant indicators of the prethrombotic state in patients with PH, such as hs-CRP, TM, Hct, ESR, CD62P, PLT, APTT, PT, TT, and FIB, showed differences. High expression of hs-CRP, TM, Hct, ESR, CD62P, and FIB, and low expression of PLT, APTT, PT, and TT are the keys to the occurrence, progression, and thrombotic state of PH. Based on the above serum indicators' expression in patients, targeted interventions can be administered to patients with abnormal expression levels to control the progression of their disease and reduce the risk of developing a prethrombotic state.

5.
Cell Death Discov ; 9(1): 402, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37903785

RESUMO

Adropin, a secreted protein, coded by energy homeostasis-associated gene (Enho), is recently reported to modulate atherogenesis, with endothelial-to-mesenchymal transition (EndMT) involved in the early process. We explored whether adropin may alleviate atherosclerosis by regulating EndMT. We found that an intraperitoneal injection of adropin [105 µg/(kg·d) for 13 weeks] inhibited the progression of high-fat diet (HFD)-induced aortic atherosclerosis in apolipoprotein E-deficient mice (ApoE-/-) and those with double gene deletion (ApoE-/-/Enho-/-), as detected by Oil Red O and haematoxylin-eosin staining. In the aortas of ApoE-/- mouse, adropin treatment ameliorated the decrease in the mRNA expression of endothelial cell markers (leukocyte differentiation antigen 31, CD31, and vascular endothelial cadherin, VE-cadherin), but increased that of EndMT markers (alpha smooth muscle actin, α-SMA, and fibroblasts specific protein-1). In vitro, an adropin treatment (30 ng/ml) arrested the hydrogen peroxide (H2O2)-induced EndMT in human umbilical vein endothelial cells (HUVECs), attenuated the morphological changes of HUVECs, reduced the number of immunofluorescence-positive α-SMA, increased the mRNA and protein expressions of CD31 and VE-cadherin, and decreased those of α-SMA. Furthermore, the adropin treatment decreased the mRNA and protein expressions of transforming growth factor (TGF)-ß1 and TGF-ß2, and suppressed the phosphorylation of downstream signal protein Smad2/3 in HUVECs. These mitigative effects of adropin on H2O2-induced EndMT were reversed by the transfection of TGF-ß plasmid. The findings signify that adropin treatment may alleviate the atherosclerosis in ApoE-/-/Enho-/- mice by inhibiting EndMT via the TGF-ß/Smad2/3 signaling pathway.

6.
Front Nutr ; 10: 1108477, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37063319

RESUMO

Background: Circulating vitamin D has been associated with multiple clinical diseases in observational studies, but the association was inconsistent due to the presence of confounders. We conducted a bidirectional Mendelian randomization (MR) study to explore the healthy atlas of vitamin D in many clinical traits and evaluate their causal association. Methods: Based on a large-scale genome-wide association study (GWAS), the single nucleotide polymorphism (SNPs) instruments of circulating 25-hydroxyvitamin D (25OHD) from 443,734 Europeans and the corresponding effects of 10 clinical diseases and 42 clinical traits in the European population were recruited to conduct a bidirectional two-sample Mendelian randomization study. Under the network of Mendelian randomization analysis, inverse-variance weighting (IVW), weighted median, weighted mode, and Mendelian randomization (MR)-Egger regression were performed to explore the causal effects and pleiotropy. Mendelian randomization pleiotropy RESidual Sum and Outlier (MR-PRESSO) was conducted to uncover and exclude pleiotropic SNPs. Results: The results revealed that genetically decreased vitamin D was inversely related to the estimated BMD (ß = -0.029 g/cm2, p = 0.027), TC (ß = -0.269 mmol/L, p = 0.006), TG (ß = -0.208 mmol/L, p = 0.002), and pulse pressure (ß = -0.241 mmHg, p = 0.043), while positively associated with lymphocyte count (ß = 0.037%, p = 0.015). The results did not reveal any causal association of vitamin D with clinical diseases. On the contrary, genetically protected CKD was significantly associated with increased vitamin D (ß = 0.056, p = 2.361 × 10-26). Conclusion: The putative causal effects of circulating vitamin D on estimated bone mass, plasma triglyceride, and total cholesterol were uncovered, but not on clinical diseases. Vitamin D may be linked to clinical disease by affecting health-related metabolic markers.

7.
J Am Heart Assoc ; 9(13): e016047, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32567476

RESUMO

Background Pro-NTs (precursor of neurotrophins) and their receptor p75 are potential targets for preventing microvascular dysfunction induced by myocardial ischemia-reperfusion injury (IRI). p75ECD (ectodomain of neurotrophin receptor p75) may physiologically produce neurocytoprotective effects by scavenging pro-NTs. We therefore hypothesized that p75ECD may have a cardioprotective effect on IRI through microvascular mechanisms. Methods and Results Myocardial IRI was induced in Sprague-Dawley rats by occluding the left main coronary arteries for 45 minutes before a subsequent relaxation. Compared with the ischemia-reperfusion group, an intravenous injection of p75ECD (3 mg/kg) 5 minutes before reperfusion reduced the myocardial infarct area at 24 hours after reperfusion (by triphenyltetrazolium chloride, 44.9±3.9% versus 34.6±5.7%, P<0.05); improved the left ventricular ejection fraction (by echocardiography), with less myocardial fibrosis (by Masson's staining), and prevented microvascular dysfunction (by immunofluorescence) at 28 days after reperfusion; and reduced myocardial pro-NTs expression at 24 hours and 28 days after reperfusion (by Western blotting). A simulative IRI model using rat microvascular pericytes was established in vitro by hypoxia-reoxygenation (2/6 hours) combined with pro-NTs treatment (3 nmol/L) at R. p75ECD (3 µg/mL) given at R improved pericyte survival (by methyl thiazolyl tetrazolium assay) and attenuated apoptosis (by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling). In the reperfused hearts and hypoxia-reoxygenation +pro-NTs-injured pericytes, p75ECD inhibited the expression of p-JNK (phospho of c-Jun N-terminal kinase)/caspase-3 (by Western blotting). SP600125, an inhibitor of JNK, did not enhance the p75ECD-induced infarct-sparing effects and pericyte protection. Conclusions p75ECD may attenuate myocardial IRI via pro-NTs reduction-induced inhibition of p-JNK/caspase-3 pathway of microvascular pericytes in rats.


Assuntos
Caspase 3/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/enzimologia , Fragmentos de Peptídeos/farmacologia , Pericitos/efeitos dos fármacos , Receptor de Fator de Crescimento Neural , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Fibrose , Masculino , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/enzimologia , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Pericitos/enzimologia , Pericitos/patologia , Fosforilação , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia , Recuperação de Função Fisiológica , Transdução de Sinais , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos
8.
Exp Ther Med ; 17(3): 1847-1854, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30783459

RESUMO

Cx43 has been documented to be involved in ischemic preconditioning (IPC). However, the participation of Cx43-formed hemichannels in IPC and the potential underlying mechanisms remain unclear. The present study focused on cardiomyocytes' volume regulation during IPC to investigate the role of hemichannels in the IPC-induced cardioprotection. In the study, mice cardiomyocytes were respectively treated with a hemichannel blocker, octanol or 18a-Glycyrrhizic acid (18a-GA), and a Cx43-silenced lentivirus. They were subsequently cultured in hypotonic solution to simulate ischemic reperfusion (SIR) and systemic ischemic preconditioning (SIP). Cell morphology and volumetric (area) change were detected by inverted microscopy at 30 min following the addition of hypotonic solution. Cardiomyocyte mortality was assessed by trypan blue stain assay. The analyses revealed that regardless of the treatments, hypotonic solution aggravated cell edema: Compared with the initial condition (the moment before the solution addition, 0 min), the volumetric area increased significantly 30 min later (for hypotonic+DMSO, 5,050±1,511 vs. 3,464±723 µm2; for hypotonic+scramble lentiviral vector, 5,517±1,128 vs. 2,331±536 µm2; P<0.05, respectively). Either treatment alleviated the edematous condition when a comparison was made between 30 min after the hypotonic addition and 0 min (for hypotonic+octanol, 2,990±765 vs. 2,821±773 µm2; for hypotonic+18a-GA, 4,817±1,306 vs. 4,762±1,271 µm2; for hypotonic+Cx43-silenced, 3,627±688 vs. 3,419±814 µm2; P>0.05 for all). Notably, results indicated that the SIP group had lower mortality rates compared with its SIR counterpart; the hypotonic+octanol, hypotonic+18a-GA, and hypotonic+Cx43-silenced group showed markedly-declined mortality when compared with their respective control groups (respectively, 35.70±1.02, 30.76±2.20 vs. 53.58±2.14%; 30.89±2.37 vs. 54.12±2.55%; P<0.05 for all). The results suggest that ischemic preconditioning may provide cardioprotection by blocking the opening of the hemichannels and further mediating the volume regulation of cardiomyocytes.

9.
Sci Rep ; 6: 33276, 2016 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-27633489

RESUMO

Detection of nitroaromatic explosives is of paramount importance from security point of view. Graphene sheets obtained from the electrochemical anodic exfoliation of graphite foil in different electrolytes (LiClO4 and Na2SO4) were compared and tested as electrode material for the electrochemical detection of 2,4-dinitrotoluene (DNT) and 2,4,6-trinitrotoluene (TNT) in seawater. Voltammetry analysis demonstrated the superior electrochemical performance of graphene produced in LiClO4, resulting in higher sensitivity and linearity for the explosives detection and lower limit of detection (LOD) compared to the graphene obtained in Na2SO4. We attribute this to the presence of oxygen functionalities onto the graphene material obtained in LiClO4 which enable charge electrostatic interactions with the -NO2 groups of the analyte, in addition to π-π stacking interactions with the aromatic moiety. Research findings obtained from this study would assist in the development of portable devices for the on-site detection of nitroaromatic explosives.

10.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 28(4): 381-387, 2016 Jul 12.
Artigo em Zh | MEDLINE | ID: mdl-29376277

RESUMO

OBJECTIVE: To clone and identify the heat shock factors (HSFs) of Schistosoma japonicum and analyze its molecular structure and alternative splicing pattern. METHODS: The New Zealand rabbits were infected with the cercariae of Schistosoma japonicum and were killed and dissected 42 days post-infection, and the adult worms of S. japonicum and the livers of the rabbits were harvested. Then, the total RNA was extracted by using Trizol reagent. The Sj-hsf open reading frame (ORF) and the alternative splicing fragments were amplified by RT-PCR from the female, male and egg samples, then cloned and verified by enzyme digestion and sequencing. DNAMAN 8.0, InterPro, Mega 6 combined with the Internet databases were utilized to clarify the gene structure, functional domains, alternative splicing pattern, and the homology and phylogenetic tree of HSFs. RESULTS: Sj-hsf ORF and the alternative splicing fragments were amplified from the female, male and egg samples of S. japonicum by RT-PCR. After cloning, the positive recombinant plasmids pBSjHSFf-F, pBSjHSFf-M, pBSjHSFf-E containing Sj-hsf ORF, pBSjHSFs-F, pBSjHSFs-M, pBSjHSFs-E with Sj-hsf alternative splicing fragments were identified by enzyme digestion and sequencing. Three alternative splicing Sj-hsf isoforms were observed through sequence analysis: Sj-hsf-isoform1 (2 050 bp), Sj-hsf -isoform2 (2 086 bp) and Sj - hsf -isoform3 (2 111 bp); the GenBank accession numbers were KU954546, KX119143 and KX119144, respectively. All the three isoforms located in the same Contig SJC_S000780 of S. japonicum genome and all expressed at female, male and egg stages, but Sj-hsf-isoform1 with a high-level expression. Sj-HSF-isoform1 (671 aa) and Sj-HSF-isoform2 (683 aa) had DBD (DNA binding domain), HR-A/B and HR-C domains, while Sj-HSF-isoform3 (282 aa) stopped in advance without HR-C domain. Phylogenetic tree analysis of HSFs illustrated that Sj - HSFs belonged to HSF1 family, with a close phylogenetic relationship to Sm-HSFs. CONCLUSIONS: There are three alternative splicing isoforms of Sj-HSF existing in the female, male and egg stages of S. japonicum, but Sj-HSF-isoform1 expresses in a high-level. This study lays the foundation for further study on molecular mechanisms of Sj-HSFs in regulating the heat shock response system.


Assuntos
Processamento Alternativo , Proteínas de Choque Térmico/genética , Proteínas de Helminto/genética , Schistosoma japonicum/genética , Animais , Sequência de Bases , Clonagem Molecular , Feminino , Masculino , Fases de Leitura Aberta/genética , Coelhos
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 24(7): 775-8, 2004 Jul.
Artigo em Zh | MEDLINE | ID: mdl-15766068

RESUMO

ZnO thin films were deposited by magnetron sputtering on SiQ2 substrates. The temperature dependence of the absorption spectra and the photoluminescence spectra was studied for ZnO thin film. The absorption of the longitudinal optical (LO) phonons and the free-excitons was observed at room temperature. The free-exciton emission was only observed in PL spectra at room temperature, the results indicate that ZnO thin films have excellent quality and low density of defects. The stimulated emission properties of ZnO thin films were investigated. When excitation intensity is above threshold, the FWHM o f stimulated emission peak increases and stimulated emission peak shows red shift with increasing excitation intensity. Our analysis shows that the optical gain is due to electronhole plasma emission.

12.
Nanoscale ; 4(20): 6307-11, 2012 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-22930365

RESUMO

Using the replica-exchange molecular dynamics method (REMD), we have investigated the size dependence of the melting behavior of iron nanoparticles. Comparing to conventional molecular dynamics (MD), the REMD method is found to be very efficient in determining the melting point by avoiding superheating and undercooling phenomena. With accurate determination of the melting point, we find that the melting temperature does not follow linearly with the inverse of size. By incorporating the size dependent thickness of surface liquid layer which is observed in our simulation, we propose a revised liquid skin melting model to describe the size dependent melting temperature.

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