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2.
Phytopathology ; 109(6): 972-982, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30714883

RESUMO

Plant survival in the terrestrial ecosystem is influenced by both beneficial and harmful microbes. Trichoderma spp. are a group of filamentous fungi that promote plant growth and resistance to harmful microbes. Previously, we showed that the genus Trichoderma could effectively suppress Fusarium wilt in cucumber. However, the mechanisms that underlie the effects of the genus Trichoderma on plant defense have not been fully substantiated. Two essential metabolic pathways, such as the ascorbate (AsA)-glutathione (GSH) cycle and the oxidative pentose phosphate pathway (OPPP), have been shown to participate in plant tolerance to biotic stressors; nevertheless, the involvement of these pathways in Trichoderma-induced enhanced defense remains elusive. Here, we show that Trichoderma harzianum could alleviate oxidative and nitrostative stress by minimizing reactive oxygen species (ROS; hydrogen peroxide and superoxide) and reactive nitrogen species (nitric oxide [NO]) accumulation, respectively, under Fusarium oxysporum infection in cucumber roots. The genus Trichoderma enhanced antioxidant potential to counterbalance the overproduced ROS and attenuated the transcript and activity of NO synthase and nitrate reductase. The genus Trichoderma also stimulated S-nitrosylated glutathione reductase activity and reduced S-nitrosothiol and S-nitrosylated glutathione content. Furthermore, the genus Trichoderma enhanced AsA and GSH concentrations and activated their biosynthetic enzymes, γ-GCS and l-galactono-1,4-lactone dehydrogenase. Interestingly, the genus Trichoderma alleviated Fusarium-inhibited activity of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase, enzymes involved in the OPPP. Such positive regulation of the key enzymes indicates the adequate maintenance of the AsA-GSH pathway and the OPPP, which potentially contributed to improve redox balance, energy flow, and defense response. Our study advances the current knowledge of Trichoderma-induced enhanced defense against F. oxysporum in cucumber.


Assuntos
Cucumis sativus , Fusarium , Doenças das Plantas/microbiologia , Trichoderma , Raízes de Plantas , Espécies Reativas de Oxigênio
3.
Huan Jing Ke Xue ; 40(1): 114-120, 2019 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-30628265

RESUMO

Characterization of the size distribution and carbon components in particulates has become important for identifying the particulates in the atmosphere. The size distribution and carbon components of atmospheric particulate matter from motor vehicles in different regions were analyzed by using Micro-orifice uniform deposition impactors (MOUDI) and the organic carbon/elemental carbon (OC/EC) analyzer. With increasing particle size, the mass concentration of raw diesel/gasoline decreases. The highest mass concentration of particles collected near the chimney of an engine laboratory was observed for particle sizes ranging from 0.32-0.56 µm, while particles with sizes from 1.0-1.8 µm in the basement garage showed the most mass fractions. The OC1, OC2, and OC3 were the major parts of the OC contents in raw diesel particles. The EC2 was the main part of EC. The atmospheric particles collected in typical regions contained more OC3 and OC4. EC1 was the main part of EC in particles collected from the basement garage. The OC/EC ratios of raw diesel particles ranged from 0.92 to 2.50. The OC/EC ratios of particles collected near the chimney of an engine laboratory ranged from 1.40 to 2.53 and that of particles collected in the basement garage ranged from 2.36 to 4.82. Moreover, the OC/EC ratios in particles collected in the basement garage normally exceeded 2.0 and reached 4.82 at the largest size, which implies that many secondary particles were generated in the basement garage. The above-mentioned characteristics provide references that are beneficial for the identification of particulates in the atmosphere originating from motor vehicles.

4.
J Cell Physiol ; 234(1): 433-442, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29932226

RESUMO

Breast cancer is known as the most prevalent cancer in women worldwide, and has an undeniable negative impact on public health, both physically, and mentally. This study aims to investigate the effects of toll-like receptor 4 (TLR4) gene silencing on proliferation and apoptosis of human breast cancer cells to explore for a new theoretical basis for its treatment. TLR4 small interference RNA (siRNA) fragment recombinant plasmids were constructed, including TLR4 siRNA-1, TLR4 siRNA-2, and TLR4 siRNA-3. Human breast cancer MCF-7 and MDA-MB-231 cells were assigned into blank, negative control (NC), TLR4 siRNA-1, TLR4 siRNA-2, and TLR4 siRNA-3 groups. MCF-7 and MDA-MB-231 cell growth was detected by MTT assay. Apoptosis and cell cycle were determined by flow cytometry. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis were conducted to determine the expression of TLR4, CDK4, cyclin D1, Livin, Bcl-2, p53, c-FLIP, and caspase-3. In comparison with the NC and blank groups, the TLR4 siRNA-1, TLR4 siRNA-2, and TLR4 siRNA-3 groups showed decreased the expression of TLR4, inhibited proliferation of MCF-7 and MDA-MB-231 cells and promoted MCF-7 and MDA-MB-231 cell apoptosis, and the cells were blocked in G1 phase. In comparison with the NC and blank groups, in the TLR4 siRNA-1, TLR4 siRNA-2, and TLR4 siRNA-3 groups, siRNA-TLR4 significantly increased expression of p53 and caspase-3 in MCF-7 and MDA-MB-231 cells, while it decreased the expressions of CDK4, cyclinD1, Livin, Bal-2, and c-FLIP. The study demonstrates that TLR4 gene silencing inhibits proliferation and induces apoptosis of MCF-7 and MDA-MB-231 cells.


Assuntos
Neoplasias da Mama/genética , Proliferação de Células/genética , Proteínas de Neoplasias/genética , Receptor 4 Toll-Like/genética , Apoptose/genética , Neoplasias da Mama/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Humanos , Células MCF-7 , Interferência de RNA , Receptor 4 Toll-Like/antagonistas & inibidores
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(9): 2894-2900, 2016 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-30084622

RESUMO

Porphyrin is a kind of photosensitizer for photodynamic therapy of cancer. Many porphyrin derivatives have been used in clinical treatment. Human Serum Albumin (HSA) is the carrier of drug transportation. Therefore, investigation on the interaction of porphyrin with HSA is very important to understand the pharmacokinetic of the porphyrin. In this paper, a new water-soluble carboxyl porphyrins, meso-tetrakis(carboxyl) zinc(Ⅱ) porphyrin (2-Zn), was synthesized and characterized. Its interaction with human serum albumin (HSA)was investigated by UV-Vis absorption spectra, fluorescence spectra, circular dichroism (CD) spectra and molecular modeling. The results indicated that the fluorescence quenching of HSA by 2-Zn was a static process with the quenching constants are 1.96×104 L·mol-1 (298 K) and 1.37×104 L·mol-1 (310 K) and the binding constants were calculated to be 1.93×104 L·mol-1 (298 K) and 1.50×104 L·mol-1 (310 K). According to the Van't Hoff equation, the thermodynamic parameters were characterized by negative enthalpy (ΔH=-16.132 kJ·mol-1) and positive entropy (ΔS=27.905 J·mol-1·K-1), which indicated that 2-Zn binds with HSA mainly via electrostatic interaction along with the hydrogen bonding and hydrophobic interaction. Site marker competitive binding experiment confirmed that 2-Zn mainly binds at site Ⅱ. The distance between HSA and the receptor (2-Zn) and the efficiency energy transfer were obtained to be 4.01 nm and 0.163 respectively, based on the Forster theory on resonance energy transfer. Synchronous fluorescence, absorption and CD spectroscopy showed that the interaction of HSA with 2-Zn induced a conformational change of protein, and the amount of α-helical structures were decrease. Furthermore, the binding details between 2-Zn and HSA were further studied with the molecular docking, which was in good agreement with the site marker competitive binding experiments and thermodynamic parameters.


Assuntos
Água/química , Sítios de Ligação , Dicroísmo Circular , Transferência de Energia , Fluorescência , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Simulação de Acoplamento Molecular , Porfirinas , Ligação Proteica , Albumina Sérica , Albumina Sérica Humana , Espectrometria de Fluorescência , Termodinâmica , Zinco
6.
Luminescence ; 30(7): 1045-54, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25736221

RESUMO

The DNA binding of amphiphilic iron(III) 2,17-bis(sulfonato)-5,10,15-tris(pentafluorophenyl)corrole complex (Fe-SC) was studied using spectroscopic methods and viscosity measurements. Its nuclease-like activity was examined by using pBR322 DNA as a target. The interaction of Fe-SC with human serum albumin (HSA) in vitro was also examined using multispectroscopic techniques. Experimental results revealed that Fe-SC binds to ct-DNA via an outside binding mode with a binding constant of 1.25 × 10(4) M(-1). This iron corrole also displays good activity during oxidative DNA cleavage by hydrogen peroxide or tert-butyl hydroperoxide oxidants, and high-valent (oxo)iron(V,VI) corrole intermediates may play an important role in DNA cleavage. Fe-SC exhibits much stronger binding affinity to site II than site I of HSA, indicating a selective binding tendency to HSA site II. The HSA conformational change induced by Fe-SC was confirmed by UV/Vis and CD spectroscopy.


Assuntos
DNA Super-Helicoidal/química , Compostos Férricos/química , Porfirinas/química , Albumina Sérica/química , Ácidos Sulfônicos/química , Tensoativos/química , Clivagem do DNA , Fluorescência , Humanos , Estrutura Molecular , Viscosidade
7.
Zhongguo Gu Shang ; 24(9): 726-8, 2011 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-22007577

RESUMO

OBJECTIVE: To explore the therapeutic effects of arthroscopy for post-traumatic chronic wrist pain. METHODS: From February 2007 to June 2010, 12 patients with post-traumatic chronic wrist pain treated with arthroscopy were reviewed. Among the patients, 9 patients were male and 3 patients were female, ranging in age from 19 to 47 years, with a mean of 35.6 years. After physical examinations or MR abnormal findings, all the patients underwent wrist arthroscopic examination and treatment. Eight patients with tear in the central area of the triangular fibrocartilage complex (TFCC) underwent endoscopic partial resection. Two patients with relaxation of inter-carpal ligament after injury underwent radiofrequency shrinkage. One patient with distal radioulnar joint instability was treated with Kirschner fixation through distal radius and ulna in the neutral forearm rotation after clean-up of wrist joint, and also fixed with long arm cast immobilization for 6 weeks. One patient with ulnar impaction syndrome was treated with wrist clean, border modeling of triangular cartilage plate, partial resection of distal ulna. RESULTS: All the patients were followed up with an average duration of 10 months. Modified Mayo wrist score were evaluated from preoperative mean of (51.67 +/- 15.27) ( 25 to 75 scores) to postoperative mean of (77.92 +/- 10.54) (65 to 95 scores). Eleven patients recovered to normal work. CONCLUSION: Arthroscopy is an effective method for patients with post-traumatic chronic wrist pain which can diagnosis and cure the injuries under arthroscopy.


Assuntos
Artroscopia/métodos , Dor/cirurgia , Articulação do Punho/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Traumatismos do Punho/patologia , Traumatismos do Punho/cirurgia , Articulação do Punho/patologia , Adulto Jovem
8.
PLoS Genet ; 6(1): e1000806, 2010 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-20072603

RESUMO

Osteoporosis is a major public health problem. It is mainly characterized by low bone mineral density (BMD) and/or low-trauma osteoporotic fractures (OF), both of which have strong genetic determination. The specific genes influencing these phenotypic traits, however, are largely unknown. Using the Affymetrix 500K array set, we performed a case-control genome-wide association study (GWAS) in 700 elderly Chinese Han subjects (350 with hip OF and 350 healthy matched controls). A follow-up replication study was conducted to validate our major GWAS findings in an independent Chinese sample containing 390 cases with hip OF and 516 controls. We found that a SNP, rs13182402 within the ALDH7A1 gene on chromosome 5q31, was strongly associated with OF with evidence combined GWAS and replication studies (P = 2.08x10(-9), odds ratio = 2.25). In order to explore the target risk factors and potential mechanism underlying hip OF risk, we further examined this candidate SNP's relevance to hip BMD both in Chinese and Caucasian populations involving 9,962 additional subjects. This SNP was confirmed as consistently associated with hip BMD even across ethnic boundaries, in both Chinese and Caucasians (combined P = 6.39x10(-6)), further attesting to its potential effect on osteoporosis. ALDH7A1 degrades and detoxifies acetaldehyde, which inhibits osteoblast proliferation and results in decreased bone formation. Our findings may provide new insights into the pathogenesis of osteoporosis.


Assuntos
Aldeído Desidrogenase/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Osteoporose/genética , Idoso , Povo Asiático/genética , Densidade Óssea , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/fisiopatologia , Polimorfismo de Nucleotídeo Único , População Branca/genética
9.
Ann Hum Biol ; 36(6): 750-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19919506

RESUMO

BACKGROUND: Economic reforms in China were implemented approximately 30 years ago. Since then, people's nutrition, living conditions and overall health have continually improved, but there has been an imbalance between the progresses in urban vs rural areas. Height and body mass index (BMI) are regarded as two important indicators of nutritional status and overall health. AIM: The aim of this study was to investigate differences in height and BMI between Chinese youths of rural vs urban areas and further, to determine whether these differences have changed over time (1990s vs 2000s). SUBJECT AND METHODS: 24 194 urban youths and 7130 rural youths were recruited in Hunan province of China. In each gender group, the subjects were divided into eight subsets according to age, geographic area residence, and decade when the youths were measured. Independent t-tests were used to test the differences of height and BMI between the studied groups. RESULTS: Both male and female youths from urban areas were significantly taller than youths from rural areas in both the 1990s and 2000s (all p<0.001), with the exception of the 1990s female 15-18 years subset (p=0.21). The height of youths was significantly greater in the 2000s compared to the corresponding gender and geographic subset in the 1990s (p<0.001), except for the female 15-18 years subset from rural areas (p=0.10). Similar results were obtained for BMI. CONCLUSION: There are significant differences in height and BMI between youths raised in urban vs rural areas, and positive growth trends of height and BMI over time (1990s vs 2000s) in youths in Hunan Province of China.


Assuntos
Estatura/fisiologia , Índice de Massa Corporal , População Rural , População Urbana , Adolescente , Criança , China , Feminino , Humanos , Masculino , Caracteres Sexuais , Fatores de Tempo
10.
J Bone Miner Res ; 23(3): 447-52, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17967140

RESUMO

UNLABELLED: A genome-wide bivariate analysis was conducted for TBLM and BMD at the spine and hip in a large white sample. We found some QTLs shared by TBLM and BMD in the entire sample and the sex-specific subgroups, and QTLs with potential pleiotropy were disclosed. INTRODUCTION: Previous studies suggested that total body lean mass (TBLM) and BMD are highly genetically correlated. However, the specific shared genetic factors between TBLM and BMD are unknown. MATERIALS AND METHODS: To identify the specific quantitative trait loci (QTLs) shared by TBLM and BMD at the spine (L1-L4) and total hip, we performed bivariate whole genome linkage analysis (WGLA) in a large sample involving 4498 white subjects of European origin. RESULTS: Multipoint bivariate linkage analyses for 22 autosomes showed evidence of significant linkage with an LOD score of 4.86 at chromosome region 15q13 for TBLM and spine BMD in women, and suggestive linkage findings (LOD > 2.2) at 7p22 for TBLM and spine BMD for the entire sample, at 7q32 for TBLM and BMD at both spine and hip in women, and at 7q21 and 13p11 for TBLM and BMD at both spine and hip in men. Two-point linkage analyses for chromosome X also showed significant linkage signals at several regions such as Xq25. Complete pleiotropy (a single locus influencing both traits) was suggested at 7q32 and 13q11 for TBLM and BMD. Additionally, complete co-incident linkage (separate tightly clustered loci each influencing a single trait) was detected at 7p22 for TBLM and spine BMD. CONCLUSIONS: We identified several genomic regions shared by TBLM and BMD in whites. Further studies may focus on fine mapping and identification of the specific QTLs in these candidate genomic regions.


Assuntos
Índice de Massa Corporal , Densidade Óssea/genética , Cromossomos Humanos/genética , Genoma Humano/genética , Escore Lod , Locos de Características Quantitativas/genética , Adulto , Idoso , Mapeamento Cromossômico , Feminino , Quadril , Humanos , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Característica Quantitativa Herdável , População Branca/genética
11.
J Inorg Biochem ; 98(6): 1143-50, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15149826

RESUMO

Three novel asymmetric ligands, 3-(pyridine-2-yl)-5,6-diphenyl-as-triazine (pdtb), 3-(pyridine-2-yl)-as-triazino[5,6-f]acenaphthylene (pdta) and 3-(pyridine-2-yl)-as-triazino[5,6-f]phenanthroline (pdtp) and their cobalt(III) complexes have been synthesized and characterized. Binding of the three complexes with calf thymus DNA (CT-DNA) has been investigated by spectroscopic methods, viscosity, cyclic voltammetry, and electrophoresis measurements. The experimental results indicate that the size and shape of the intercalated ligand have a marked effect on the binding affinity of complexes to CT-DNA. Complexes 2 and 3 have also been found to promote cleavage of plasmid pBR322 DNA from the supercoiled form I to the open circular form II upon irradiation.


Assuntos
Acenaftenos/química , Cobalto/química , DNA/química , Compostos Organometálicos/química , Fenantrolinas/química , Plasmídeos/química , Piridinas/química , Triazinas/química , Acenaftenos/síntese química , Animais , Bovinos , Ligantes , Compostos Organometálicos/síntese química , Fenantrolinas/síntese química , Fotoquímica , Piridinas/síntese química , Triazinas/síntese química
12.
J Inorg Biochem ; 98(3): 423-9, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14987842

RESUMO

Two asymmetric tridentate copper(II) complexes, [Cu(dppt)Cl(2)].0.25H(2)O (1) (dppt=3-(1,10-phenanthrolin-2-yl)-5,6-diphenyl-as-triazine) and [Cu(pta)Cl(2)] (2) (pta=3-(1,10-phenanthrolin-2-yl)-as-triazino[5,6-f]acenaphthylene), have been prepared and characterized by elemental analysis, IR and Fast atomic bombardment mass spectra. Complex 1 has also been structurally characterized. The complexes exist as distorted square pyramid with five co-ordination sites occupied by the tridentate ligand and the two chlorine anions. DNA interaction studies suggest that the ligand planarity of the complex has a significant effect on DNA binding affinity increasing in the order [Cu(dppt)Cl(2)]< [Cu(pta)Cl(2)]. In the presence of ascorbate or glutathione, the two complexes are found to cause significant cleavage of double-strand pBR 322 DNA and [Cu(pta)Cl(2)] exhibited the higher cleaving efficiency.


Assuntos
Cobre/química , DNA/química , Compostos Organometálicos/química , Animais , Bovinos , Cristalografia por Raios X , DNA/metabolismo , Eletroquímica/métodos , Ligantes , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/metabolismo , Fenantrolinas/química , Plasmídeos/metabolismo , Espectrometria de Fluorescência , Espectrofotometria Infravermelho , Triazinas/química
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