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1.
J Int Med Res ; 48(12): 300060520977403, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33290111

RESUMO

OBJECTIVE: To analyze the factors contributing to recurrence in patients with pT3N0M0 thoracic esophageal squamous cell carcinoma (ESCC). METHODS: Patients with pT3N0M0 thoracic ESCC who underwent esophagectomy from January 2008 to December 2012 were included retrospectively. The last date of follow-up was 1 December 2016. Multivariate proportional hazard Cox models were used to identify factors associated with total (i.e., any) recurrence (TR), locoregional recurrence (LR), and distant metastasis (DM). RESULTS: A total of 692 patients were included. The median follow-up was 53 months (range: 3-107). The 3- and 5-year TR, LR, and DM rates were 35.8% and 41.0%, 28.7% and 32.1%, and 16.8% and 21.1%, respectively. The Cox analyses showed that the tumor location, number of dissected lymph nodes, and postoperative therapies were significantly associated with LR. The subgroup analysis showed that postoperative therapies could significantly decrease LR in the mediastinum but not in the neck and upper abdomen regions. CONCLUSIONS: The recurrence rate of pT3N0M0 thoracic ESCC patients was high, especially for LR in the mediastinum. Postoperative therapies can significantly reduce the incidence of mediastinal recurrence.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Idoso , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Carcinoma de Células Escamosas do Esôfago/cirurgia , Esofagectomia/efeitos adversos , Feminino , Humanos , Excisão de Linfonodo , Linfonodos/patologia , Linfonodos/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Estudos Retrospectivos , Fatores de Risco
2.
Viral Immunol ; 31(6): 417-425, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29672235

RESUMO

Signaling through interleukin (IL)-7 is essential and required for development, differentiation, proliferation, and homeostasis of T cells. However, the role of IL-7 in regulation of CD4+ T cells in chronic viral infections was not fully elucidated. Thus, the aim of the current study was to investigate the immunomodulatory activity of IL-7 to T follicular helper (Tfh) cells and its contribution to pathogenesis of chronic HCV, hepatitis C virus (HCV) infection. A total of 47 patients with chronic hepatitis C and 19 normal controls were enrolled. Serum IL-7 and proportion of Tfh cells was measured. The regulatory function of IL-7 to Tfh cells was also investigated in CD4+ T cells and CD4+ T/HCVcc-infected Huh7.5 cell cocultured system. Serum IL-7 concentration was significantly downregulated in patients with chronic hepatitis C, and was negatively correlated with HCV RNA level. Tfh frequency and Tfh-associated cytokines (IL-21 and IL-6) were also reduced in chronic HCV-infected patients. Moreover, recombinant IL-7 stimulation elevated proportion of Tfh cells and IL-21/IL-6 secretion in both HCV-specific and nonspecific manners. Furthermore, IL-7-treated CD4+ T cells exhibited elevated antiviral activities without killing infected hepatocytes, which presented as inhibition of HCV RNA, induction of antiviral proteins, and promotion of cytokine production (especially IL-21) in cocultured system. This process might be dependent on IL-6 secretion. The current data revealed that IL-7 regulated HCV-specific and nonspecific activated Tfh cells, which might contribute to viral clearance. IL-7 could be a potential therapeutic agent for the treatment of chronic hepatitis C.


Assuntos
Hepacivirus/imunologia , Hepatite C Crônica/imunologia , Interleucina-7/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Linhagem Celular Tumoral , Técnicas de Cocultura , Regulação para Baixo , Feminino , Hepacivirus/isolamento & purificação , Hepatite C Crônica/sangue , Hepatite C Crônica/virologia , Hepatócitos , Humanos , Interleucina-7/sangue , Interleucina-7/metabolismo , Masculino , Cultura Primária de Células , Linfócitos T Auxiliares-Indutores/metabolismo
3.
Viral Immunol ; 30(7): 522-532, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28410452

RESUMO

Notch signaling enhanced the response of interleukin (IL)-22-producing CD4+ T cells that were defined as T helper 22 (Th22) cells, and Notch-aryl hydrocarbon receptor (AhR)-IL-22 axis fine-tuned inflammatory response. Previous studies have demonstrated that both Notch signaling and Th22 cells took part in the pathogenesis of chronic hepatitis C virus (HCV) infection. Thus, in this study, we aimed at examining the regulatory role of Notch signaling in Th22 cells in HCV infection. A total of 59 patients with chronic hepatitis C and 22 normal controls (NCs) were enrolled in this study. The percentage of Th22 cells and mRNA expression of related transcriptional factors and cytokines were analyzed in response to γ-secretase inhibitor. Th22 cell frequency was significantly elevated in chronic hepatitis C in comparison with that in NCs. Inhibition of Notch signaling downregulated HCV-specific Th22 cells and IL-22 production, which was accompanied by the reduction of AhR and modulatory cytokines (IL-6 and tumor necrosis factor-α). Moreover, the suppression of Notch signaling also decreased the IL-22-mediated antimicrobial response in both normal and HCV-infected HepG2 cells/Huh7.5 cells. This process was also accompanied by the depression of signal transducers and activators of transcription 3 signaling. In conclusion, the current results suggested that Notch signaling acted as a critical pathway in determining the response to IL-22 in chronic hepatitis C. Thus, Notch-Th22 axis might be considered a new therapeutic target for HCV-infected patients.


Assuntos
Hepatite C Crônica/imunologia , Receptor Notch1/metabolismo , Receptor Notch2/metabolismo , Transdução de Sinais , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismo , Adulto , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Linhagem Celular Tumoral , Citocinas/metabolismo , Feminino , Regulação da Expressão Gênica , Células Hep G2 , Hepatite C Crônica/sangue , Hepatite C Crônica/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Receptor Notch1/genética , Receptor Notch2/genética , Receptores de Hidrocarboneto Arílico/genética , Fator de Transcrição STAT3/metabolismo , Adulto Jovem
4.
Neural Regen Res ; 11(7): 1115-21, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27630695

RESUMO

Major ozonated autohemotherapy has been shown to promote recovery of upper limb motor function in patients with acute cerebral infarction, but whether major ozonated autohemotherapy affects remote injury remains poorly understood. Here, we assumed that major ozonated autohemotherapy contributes to recovery of clinical function, possibly by reducing remote injury after acute cerebral infarction. Sixty acute cerebral infarction patients aged 30-80 years were equally and randomly allocated to ozone treatment and control groups. Patients in the ozone treatment group received medical treatment and major ozonated autohemotherapy (47 mg/L, 100 mL ozone) for 10 ± 2 days. Patients in the control group received medical treatment only. National Institutes of Health Stroke Scale score, modified Rankin scale score, and reduced degree of fractional anisotropy values of brain magnetic resonance diffusion tensor imaging were remarkably decreased, brain function improved, clinical efficiency significantly increased, and no obvious adverse reactions detected in the ozone treatment group compared with the control group. These findings suggest that major ozonated autohemotherapy promotes recovery of neurological function in acute cerebral infarction patients by reducing remote injury, and additionally, exhibits high safety.

5.
Viral Immunol ; 29(6): 322-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27082819

RESUMO

Regulatory T cells (Tregs) and interleukin-17-producing T helper (Th17) cells were mutually antagonistic in the pathogenesis of chronic hepatitis C virus (HCV) infection. However, the regulation of imbalance between Tregs and Th17 cells was poorly understood in HCV infection. A recent report revealed the immunomodulatory role of Toll-like receptor (TLR) 2 in regulating the balance of Tregs/Th17 functions in multiple sclerosis. Thus, the aim of the current study was to assess the effect of TLR2 stimulation on the suppressive function of Tregs and Th17 differentiation in chronic hepatitis C. A total of 65 patients with chronic hepatitis C receiving pegylated interferon-a2a and ribavirin therapy for 48 weeks, as well as 20 of normal controls (NCs) were enrolled. Cellular proliferation and cytokine production was tested in purified CD4(+)CD25(+)CD127(dim/-) Tregs in response to the stimulation of Pam3Csk4, an agonist of TLR2. In treatment-naive patients, Tregs, but not Th17 cells, from chronic hepatitis C patients expressed higher levels of TLR2 compared with NCs. Stimulation with Pam3Csk4 enhanced the suppressive function of Tregs and production of IL-10 in chronic hepatitis C more than in NCs. However, TLR2 stimulation did not promote Th17 differentiation of Tregs in chronic hepatitis C patients. Moreover, effective anti-HCV therapy resulted in the induction of IL-17-secreting phenotypic shift of Tregs without loss of inhibitive function upon TLR2 stimulation. These data provided a novel mechanism underlying modulating the balance of Tregs/Th17 cells in chronic hepatitis C. HCV infection shifted Tregs/Th17 cells through TLR2 stimulation by inducing Tregs to produce IL-10 and enhancing inhibitive function of effector T cells, resulting in viral persistence.


Assuntos
Hepatite C Crônica/patologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Receptor 2 Toll-Like/metabolismo , Adulto , Antivirais/uso terapêutico , Proliferação de Células , Citocinas/metabolismo , Feminino , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico , Adulto Jovem
6.
Eur J Med Chem ; 87: 10-22, 2014 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-25238290

RESUMO

Two new Ru(II) complexes, [Ru(Htip)3]Cl2 (1) and [Ru(Htip)2(dppz)]Cl2 (2), were synthesised and were characterised. The ground- and excited-state acid-base properties of 1 and 2 were studied and demonstrated that 1 acted as a pH-induced "on-off-on" luminescence switch. The binding behaviours of 1 and 2 to calf thymus DNA were studied with absorption and emission spectroscopy, DNA viscosities and density functional theory calculations. 2 was found to act as a DNA molecular light switch and as an efficient photocleaver of pUC 18 DNA. The cytotoxicities of the complexes were evaluated with the MTT method and it was found that 1 displayed apparent anticancer activity against MCF-7 cell, whereas 2 exhibited more potent and wider-spectrum antitumor activities against all cancer cell lines tested.


Assuntos
Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/química , Clivagem do DNA/efeitos dos fármacos , DNA/metabolismo , Luz , Compostos Organometálicos/farmacologia , Rutênio/química , Tiofenos/química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Bovinos , Proliferação de Células/efeitos da radiação , DNA/química , DNA/efeitos da radiação , Clivagem do DNA/efeitos da radiação , Humanos , Concentração de Íons de Hidrogênio , Luminescência , Estrutura Molecular , Neoplasias/tratamento farmacológico , Compostos Organometálicos/química , Teoria Quântica , Relação Estrutura-Atividade , Células Tumorais Cultivadas
7.
J Plant Physiol ; 170(13): 1139-47, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23683508

RESUMO

To understand the photosynthetic basis in a single seed descent line 10 (SSDL10) of wheat contained high ATP in leaves, the chloroplast proteome was compared to SSDL10 and its parents using a combination of 2-DE and MALDI-TOF MS and MS/MS. More than 300 protein spots could be reproducibly detected in the 2D gel. 18 spots were differentially expressed between SSDL10 and the parents, 16 of which were identified by MS with the localization in chloroplasts. These proteins are grouped into diverse functional categories, including Calvin cycle and electron transport in photosynthesis, redox homeostasis, metabolism, and regulation. In addition to Rubisco large subunit, the content of photosynthetic electron transfers such as chlorophyll a-b binding protein, ATP synthase δ subunit, ferredoxin-NADP⁺ oxidoreductase (FNR) was higher in SSDL10 than in its parents. Furthermore, cyclic electron transfer around photosystem I (CET) was faster in SSDL10 than in the parents. Analysis of NADPH-NBT oxidoreductase activity combined with immuno-detection further revealed that, the activity of two high molecular mass protein complexes containing FNR probably involved, the CET appeared higher in SSDL10 than in the parents. The possible mechanism for the regulative role of CET in photosynthesis in SSDL10 is discussed.


Assuntos
Cloroplastos/metabolismo , Complexo de Proteína do Fotossistema I/metabolismo , Proteoma/metabolismo , Triticum/metabolismo , Transporte de Elétrons , Fotossíntese , Folhas de Planta/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem , Triticum/genética
8.
Dalton Trans ; 42(16): 5764-77, 2013 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-23450276

RESUMO

The ground- and excited-state acid-base properties of [Ru2(bpy)4(H2bipt)]Cl4 1 {bpy = 2,2'-bipyridine, H2bipt = 2,5-bis[1,10]phenanthrolin[4,5-f]-imidazol-2-yl)thiophene} are investigated by emission and UV-visible absorption spectrophotometric pH titrations. The DNA binding properties of 1 are studied by means of DNA viscosity and optical spectroscopic techniques of UV-visible absorption and emission spectral titrations, steady-state emission quenching with ferrocyanide, ethidium bromide competitive binding, and DNA thermal denaturation as well as density functional theoretical calculations. The DNA photocleavage and singlet oxygen generation properties as well as in vitro anticancer activities against five cancer cell lines are studied as well. The results demonstrated that pH-induced luminescence switching, DNA binding, and anticancer properties of 1 are much improved with respect to those of the mononuclear analog [Ru(bpy)2(Htip)]Cl2 {Htip = 2-(thiophen-2-yl)-1H-imidazo[4,5-f][1,10]phenanthroline}.


Assuntos
Antineoplásicos/química , Complexos de Coordenação/química , DNA/metabolismo , Rutênio/química , Antineoplásicos/metabolismo , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Complexos de Coordenação/metabolismo , Complexos de Coordenação/toxicidade , DNA/química , Células HeLa , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Desnaturação de Ácido Nucleico , Fotólise , Teoria Quântica , Oxigênio Singlete/metabolismo , Espectrofotometria Ultravioleta
9.
J Exp Bot ; 64(5): 1403-11, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23382547

RESUMO

The adaptations of root morphology, physiology, and biochemistry to phosphorus supply have been characterized intensively. However, characterizing these adaptations at molecular level is largely neglected under field conditions. Here, two consecutive field experiments were carried out to investigate the agronomic traits and root traits of wheat (Triticum aestivum L.) at six P-fertilizer rates. Root samples were collected at flowering to investigate root dry weight, root length density, arbusular-mycorrhizal colonization rate, acid phosphatase activity in rhizosphere soil, and expression levels of genes encoding phosphate transporter, phosphatase, ribonucleases, and expansin. These root traits exhibited inducible, inhibitory, or combined responses to P deficiency, and the change point for responses to P supply was at or near the optimal P supply for maximum grain yield. This research improves the understanding of mechanisms of plant adaptation to soil P in intensive agriculture and provides useful information for optimizing P management based on the interactions between soil P dynamics and root processes.


Assuntos
Fósforo/farmacologia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/genética , Triticum/anatomia & histologia , Triticum/genética , Biomassa , Flores/efeitos dos fármacos , Flores/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas/genética , Fósforo/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/genética , Brotos de Planta/metabolismo , Solo , Triticum/efeitos dos fármacos , Triticum/crescimento & desenvolvimento
10.
Colloids Surf B Biointerfaces ; 96: 29-36, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22503631

RESUMO

Previous studies have shown that piezoelectric materials may be used to prepare bioactive electrically charged surfaces. In the current study, polyurethane/polyvinylidene fluoride (PU/PVDF) scaffolds were prepared by electrospinning. The mechanical property and piezoelectric property of the scaffolds were evaluated. The crystalline phase of PVDF in the scaffolds was characterised by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). In vitro cell culture was performed to investigate cytocompatibility of the scaffolds. Wound-healing assay, cell-adhesion assay, quantitative RT-PCR and Western blot analyses were performed to investigate piezoelectric effect of the scaffolds on fibroblast activities. Further, the scaffolds were subcutaneously implanted in Sprague-Dawley (SD) rats to investigate their biocompatibility and the piezoelectric effect on fibrosis in vivo. The results indicated that the electrospinning process had changed PVDF crystalline phase from the nonpiezoelectric α phase to the piezoelectric ß phase. The fibroblasts cultured on the scaffolds showed normal morphology and proliferation. The fibroblasts cultured on the piezoelectric-excited scaffolds showed enhanced migration, adhesion and secretion. The scaffolds that were subcutaneously implanted in SD rats showed higher fibrosis level due to the piezoelectrical stimulation, which was caused by random animal movements followed by mechanical deformation of the scaffolds. The scaffolds are potential candidates for wound healing applications.


Assuntos
Materiais Biocompatíveis/farmacologia , Poliuretanos/química , Polivinil/química , Alicerces Teciduais/química , Cicatrização/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Western Blotting , Varredura Diferencial de Calorimetria , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Elastina/genética , Elastina/metabolismo , Eletricidade , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/ultraestrutura , Fibronectinas/genética , Fibronectinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Camundongos , Microscopia Confocal , Microscopia Eletrônica de Varredura , Células NIH 3T3 , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
11.
New Phytol ; 189(2): 449-58, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21039562

RESUMO

Glutamine synthetase (GS) plays a key role in the growth, nitrogen (N) use and yield potential of cereal crops. Investigating the haplotype variation of GS genes and its association with agronomic traits may provide useful information for improving wheat N-use efficiency and yield. We isolated the promoter and coding region sequences of the plastic glutamine synthetase isoform (GS2) genes located on chromosomes 2A, 2B and 2D in bread wheat. By analyzing nucleotide sequence variations of the coding region, two, six and two haplotypes were distinguished for TaGS2-A1 (a and b), TaGS2-B1 (a-f) and TaGS2-D1 (a and b), respectively. By analyzing the frequency data of different haplotypes and their association with N use and agronomic traits, four major and favorable TaGS2 haplotypes (A1b, B1a, B1b, D1a) were revealed. These favorable haplotypes may confer better seedling growth, better agronomic performance, and improved N uptake during vegetative growth or grain N concentration. Our data suggest that certain TaGS2 haplotypes may be valuable in breeding wheat varieties with improved agronomic performance and N-use efficiency.


Assuntos
Pão , Glutamato-Amônia Ligase/genética , Haplótipos/genética , Nitrogênio/metabolismo , Característica Quantitativa Herdável , Triticum/enzimologia , Triticum/genética , Alelos , China , Cruzamentos Genéticos , Genes de Plantas/genética , Glutamato-Amônia Ligase/metabolismo , Haploidia , Hidroponia , Endogamia , Isoenzimas/genética , Isoenzimas/metabolismo , Dados de Sequência Molecular , Recombinação Genética/genética , Plântula/genética , Plântula/crescimento & desenvolvimento , Homologia de Sequência do Ácido Nucleico , Triticum/crescimento & desenvolvimento
12.
World J Gastroenterol ; 14(38): 5907-12, 2008 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-18855992

RESUMO

AIM: To assess the effects of H(2)-receptor blocking pharmacon, protease inhibitor, and gastro kinetic agents on the human Sphincter of Oddi (SO) motility by choledochoscope manometry. METHODS: One hundred and seventy-five patients with T tube installed after cholecystectomy and choledochotomy were assessed by choledochoscope manometry. They were randomly assigned into groups of H(2)-receptor blocking pharmacon, protease inhibitor, and gastro kinetic agents. The Sphincter of Oddi basal pressure (SOBP), amplitude (SOCA), frequency of contractions (SOF), duodenal pressure (DP), and common bile duct pressure (CBDP) were scored and analyzed. RESULTS: SOBP and SOCA were significantly decreased after cimetidine administration, and no statistical difference was seen in the famotidine group. In the gabexate mesilate group, SOBP had decreased significantly. In the ulinastatin group, SOCA decreased when ulinastatin was given at the rate of 2500 U/min; when ulinastatin administration was raised to 5000 U/min, SOBP, SOF and SOCA all experienced a fall. SOBP and SOCA for domperidone and SOCA for mosapride groups all decreased distinctly after administration. CONCLUSION: The regular dosage of cimetidine showed an inhibitory effect on the motility of SO, while famotidine had no obvious effects otherwise. Gabnexata mesilate, ulinastatin and gastro kinetic agents also showed inhibitory effects on the SO motility.


Assuntos
Endoscópios , Fármacos Gastrointestinais/uso terapêutico , Antagonistas dos Receptores H2 da Histamina/uso terapêutico , Manometria/instrumentação , Inibidores de Serina Proteinase/uso terapêutico , Esfíncter da Ampola Hepatopancreática/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Benzamidas/uso terapêutico , Colecistectomia , Cimetidina/uso terapêutico , Domperidona/uso terapêutico , Famotidina/uso terapêutico , Feminino , Gabexato/uso terapêutico , Glicoproteínas/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Morfolinas/uso terapêutico , Contração Muscular/efeitos dos fármacos , Pressão , Esfíncter da Ampola Hepatopancreática/fisiopatologia , Adulto Jovem
13.
J Integr Plant Biol ; 50(4): 443-51, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18713378

RESUMO

Rice has a preference for uptake of ammonium over nitrate and can use ammonium-N efficiently. Consequently, transporters mediating ammonium uptake have been extensively studied, but nitrate transporters have been largely ignored. Recently, some reports have shown that rice also has high capacity to acquire nitrate from growth medium, so understanding the nitrate transport system in rice roots is very important for improving N use efficiency in rice. The present study identified four putative NRT2 and two putative NAR2 genes that encode components of the high-affinity nitrate transport system (HATS) in the rice (Oryza sativa L. subsp. japonica cv. Nipponbare) genome. OsNRT2.1 and OsNRT2.2 share an identical coding region sequence, and their deduced proteins are closely related to those from mono-cotyledonous plants. The two NAR2 proteins are closely related to those from mono-cotyledonous plants as well. However, OsNRT2.3 and OsNRT2.4 are more closely related to Arabidopsis NRT2 proteins. Relative quantitative reverse transcription-polymerase chain reaction analysis showed that all of the six genes were rapidly upregulated and then downregulated in the roots of N-starved rice plants after they were re-supplied with 0.2 mM nitrate, but the response to nitrate differed among gene members. The results from phylogenetic tree, gene structure and expression analysis implied the divergent roles for the individual members of the rice NRT2 and NAR2 families. High-affinity nitrate influx rates associated with nitrate induction in rice roots were investigated and were found to be regulated by external pH. Compared with the nitrate influx rates at pH 6.5, alkaline pH (pH 8.0) inhibited nitrate influx, and acidic pH (pH 5.0) enhanced the nitrate influx in 1 h nitrate induced roots, but did not significantly affect that in 4 to 8 h nitrate induced roots.


Assuntos
Proteínas de Transporte de Ânions/genética , Regulação da Expressão Gênica de Plantas , Ordem dos Genes , Oryza/genética , Raízes de Plantas/genética , Proteínas de Transporte de Ânions/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ordem dos Genes/efeitos dos fármacos , Genes de Plantas , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Transportadores de Nitrato , Nitratos/farmacologia , Oryza/efeitos dos fármacos , Filogenia , Raízes de Plantas/efeitos dos fármacos , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
14.
Yi Chuan Xue Bao ; 29(3): 255-9, 2002.
Artigo em Chinês | MEDLINE | ID: mdl-12182082

RESUMO

Transferring useful chromosome(s), chromosomal fragment(s) or genes from related species into common wheat (Triticum aestivum L.) is an effective method for improving wheat cultivars, and DNA:DNA in situ hybridization has been proven to be an effective method for directly demonstrating alien chromosome number and distribution in plant. In this study, genomic in situ hybridization (GISH) was used to identify the chromosomal constitutions of the blue-grained wheat Blue-58 originated from distant hybridization between Triticum aestivum L. and Agropyron elongatum (Host) Beauv (2n = 10x = 70) and its irradiation-mutated offsprings. The results showed that, as previously reported, Blue-58 (2n = 42) was a substitution line in which a pair of 4D chromosomes of common wheat was substituted by a pair of 4E chromosomes from Agropyron elongatum. Mutation line LW004 might be a homozygous reciprocal translocation line in which two pair of chromosomes might be involved in the translocation event and it showed high efficiency in utilizing soil phosphorus in our field screening experiments. Mutation line LW43-3-4 was a blue monosomic line with 40 wheat chromosomes plus one 4E chromosome from Agropyron elongatum in its genome and its seeds showed light-blue color. Some other chromosome rearrangements and structure changes were also detected among the mutated offsprings through GISH, such as telomonosomic line (40 W + 1't4E) and a line with a chromosomal constitution of 39 W + 1'4E + 1't4E. Our results indicated very clearly that it was the chromosome derived from Agropyron elongatum carried gene(s) responsible for the blue pigmentation in wheat grains and it was also illustrated from our results that the combination of effective methods for generating mutations at chromosomal level and convenient detection of these mutations played pivotal roles in creating materials for chromosome engineering and in breeding by means of chromosome engineering.


Assuntos
Hibridização In Situ , Triticum/genética , Mutação , Triticum/efeitos da radiação
15.
Yi Chuan Xue Bao ; 29(11): 1017-20, 2002.
Artigo em Chinês | MEDLINE | ID: mdl-12645267

RESUMO

Phosphorus is a major nutrient acquired by plants and phosphorus availability is considered one of the major growth-limiting factors for plants in many natural ecosystems. For a better understanding of the function of the wheat phosphorus transporter gene named TaPT2, we did Southern blot analysis and studied its function with complementation test in yeast mutant strain MB192. Southern blot indicated that TaPT2 gene is a low-copy member and has several different members in wheat genome. In the function complementation study, TaPT2 has a similar function as PHO84 which is the phosphate transporter in yeast Saccharomyces cerevisiae. Both TaPT2 and PHO84 are able to complement the PHO84 mutant phenotype of yeast strain MB192 which lacks the phosphate transporter activity. Therefor, this assessment presents evidence that TaPT2 gene plays an important role in Pi acquisition.


Assuntos
Proteínas de Transporte de Fosfato/metabolismo , Saccharomyces cerevisiae/genética , Triticum/genética , Southern Blotting , Divisão Celular/genética , DNA de Plantas/genética , Teste de Complementação Genética , Mutação , Proteínas de Transporte de Fosfato/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Triticum/metabolismo
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