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1.
Gastric Cancer ; 24(2): 535-543, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33118118

RESUMO

BACKGROUND: The appropriate surgical procedure for patients with upper third early gastric cancer is controversial. We compared total gastrectomy (TG) with proximal gastrectomy (PG) in this patient population. METHODS: A multicenter, non-randomized trial was conducted, with patients treated with PG or TG. We compared short- and long-term outcomes between these procedures. RESULTS: Between 2009 and 2014, we enrolled 254 patients from 22 institutions; data from 252 were included in the analysis. These 252 patients were assigned to either the PG (n = 159) or TG (n = 93) group. Percentage of body weight loss (%BWL) at 1 year after surgery, i.e., the primary endpoint, in the PG group was significantly less than that of the TG group (- 12.8% versus - 16.9%; p = 0.0001). For short-term outcomes, operation time was significantly shorter for PG than TG (252 min versus 303 min; p < 0.0001), but there were no group-dependent differences in blood loss and postoperative complications. For long-term outcomes, incidence of reflux esophagitis in the PG group was significantly higher than that of the TG group (14.5% versus 5.4%; p = 0.02), while there were no differences in the incidence of anastomotic stenosis between the two (5.7% versus 5.4%; p = 0.92). Overall patient survival rates were similar between the two groups (3-year survival rates: 96% versus 92% in the PG and TG groups, respectively; p = 0.49). CONCLUSIONS: Patients who underwent PG were better able to control weight loss without worsening the prognosis, relative to those in the TG group. Optimization of a reconstruction method to reduce reflux in PG patients will be important.


Assuntos
Gastrectomia/métodos , Neoplasias Gástricas/cirurgia , Estômago/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica , Feminino , Gastrectomia/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Duração da Cirurgia , Prognóstico , Estudos Prospectivos , Estômago/patologia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Taxa de Sobrevida , Resultado do Tratamento , Redução de Peso
3.
Cytopathology ; 29(3): 254-261, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29626374

RESUMO

INTRODUCTION: Positive peritoneal cytology (PPC) in endometrial cancer remains a controversial topic. Cleaved caspase-3 (CC3) and Ki-67 are excellent markers of apoptotic and proliferating cells, respectively. The objective of this study was to determine the significance of CC3 and Ki-67 expression in peritoneal cytology samples as prognostic factors for endometrial cancer with PPC. METHODS: Sixty endometrial cancer specimens with PPC alone were divided into 51 endometrioid tumours (43 endometrioid carcinomas and eight carcinomas with squamous differentiation) and nine non-endometrioid tumours (two serous carcinomas, three clear cell carcinomas and four carcinosarcomas). CC3 and Ki-67 expression in peritoneal cytology samples were immunocytochemically assessed and correlated with disease-free survival (DFS) and overall survival (OS). RESULTS: Expression levels of CC3 and Ki-67 were not associated with any clinicopathological parameter. Patients with non-endometrioid tumours had significantly shorter DFS (P = .001) and OS (P = .001). Low CC3 expression (CC3Low ) was significantly associated with shorter OS (P = .02), but not DFS (P = .13). Multivariate analysis showed that non-endometrioid histology and CC3Low were independent prognostic factors. However, Ki-67 expression was not associated with survival. When endometrioid and non-endometrioid tumours were assessed separately, CC3Low was significantly associated with shorter DFS (P = .002) and OS (P = .002) in patients with non-endometrioid tumours. CONCLUSIONS: Our results suggest that CC3Low in peritoneal cytology samples is a poor prognostic factor in patients with endometrial cancers, especially non-endometrioid tumours. Immunocytochemical analysis of CC3 expression could potentially facilitate identification of patients with high-risk endometrial cancer with PPC.


Assuntos
Caspase 3/metabolismo , Neoplasias do Endométrio/metabolismo , Peritônio/metabolismo , Adenocarcinoma de Células Claras/metabolismo , Adenocarcinoma de Células Claras/patologia , Apoptose/fisiologia , Carcinoma Endometrioide/metabolismo , Carcinoma Endometrioide/patologia , Proliferação de Células/fisiologia , Intervalo Livre de Doença , Neoplasias do Endométrio/patologia , Feminino , Humanos , Antígeno Ki-67/metabolismo , Pessoa de Meia-Idade , Peritônio/patologia , Prognóstico , Estudos Retrospectivos , Fatores de Risco
4.
Ann Oncol ; 28(1): 116-120, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27687307

RESUMO

BACKGROUND: This phase II trial evaluated the efficacy of cisplatin and fluorouracil (CF)-based combination neoadjuvant chemotherapy on the outcome of patients with resectable locally advanced esophageal squamous cell carcinoma (ESCC). We compared the recurrence-free survival (RFS) associated with CF plus Adriamycin (ACF) with that associated with CF plus docetaxel (DCF) to select an alternative regimen in a new phase III trial investigating the optimal neoadjuvant treatment of patients with ESCC. PATIENTS AND METHODS: Patients with resectable advanced ESCC were randomly assigned to either ACF (Adriamycin 35 mg/m2, cisplatin 70 mg/m2 i.v. on day 1, fluorouracil 700 mg/m2 continuous infusion for 7 days) every 4 weeks or DCF (docetaxel 70 mg/m2, cisplatin 70 mg/m2 i.v. on day 1, fluorouracil 700 mg/m2 continuous infusion for 5 days) every 3 weeks. Surgery was scheduled after completion of two cycles of chemotherapy. The primary end point was RFS, analyzed by the intention-to-treat. RESULTS: Between October 2011 and October 2013, 162 patients at 10 institutions were enrolled in the study, all of whom were eligible and randomly assigned to the two groups (81 to the ACF group and 81 to the DCF group). The R0 resection rates for the ACF and DCF groups were equivalent (95.9% versus 96.2%, P = 0.93). The 2-year RFS and overall survival rates for DCF versus ACF were 64.1% versus 42.9% (hazard ratio 0.53, 95% confidence interval 0.33-0.83, P = 0.0057) and 78.6% versus 65.4% (P = 0.08), respectively. CONCLUSION: Compared with ACF, DCF chemotherapy was associated with prolonged RFS for patients with resectable advanced ESCC. Thus, DCF chemotherapy has potential as a standard neoadjuvant therapy for resectable ESCC. CLINICAL TRIAL REGISTRATION: University Hospital Medical Information Network Clinical Trials Registry of Japan (identification number UMIN000004555/000004616).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Doxorrubicina/administração & dosagem , Neoplasias Esofágicas/tratamento farmacológico , Taxoides/administração & dosagem , Adulto , Idoso , Carcinoma de Células Escamosas/mortalidade , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Intervalo Livre de Doença , Docetaxel , Doxorrubicina/efeitos adversos , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Taxoides/efeitos adversos , Resultado do Tratamento
5.
Clin Exp Immunol ; 190(1): 133-142, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28617941

RESUMO

The cause of pleural effusion remains uncertain in approximately 15% of patients despite exhaustive evaluation. As recently described immunoglobulin (Ig)G4-related disease is a fibroinflammatory disorder that can affect various organs, including the lungs, we investigate whether idiopathic pleural effusion includes IgG4-associated etiology. Between 2000 and 2012, we collected 830 pleural fluid samples and reviewed 35 patients with pleural effusions undiagnosed after pleural biopsy at Yamaguchi-Ube Medical Center. Importantly, IgG4 immunostaining revealed infiltration of IgG4-positive plasma cells in the pleura of 12 patients (34%, IgG4+ group). The median effusion IgG4 level was 41 mg/dl in the IgG4+ group and 27 mg/dl in the IgG4- group (P < 0·01). The light and heavy chains of effusion IgG4 antibodies of patients in the IgG4+ group were heterogeneous by two-dimensional electrophoresis, indicating the absence of clonality of the IgG4 antibodies. Interestingly, the κ light chains were more heterogeneous than the λ light chains. The measurement of the κ and λ free light chain (FLC) levels in the pleural fluids showed significantly different κ FLC levels (median: 28·0 versus 9·1 mg/dl, P < 0·01) and κ/λ ratios (median: 2·0 versus 1·2, P < 0·001) between the IgG4+ and IgG4- groups. Furthermore, the κ/λ ratios were correlated with the IgG4+ /IgG+ plasma cell ratios in the pleura of the IgG4+ group. Taken together, these results demonstrate the involvement of IgG4 in certain idiopathic pleural effusions and provide insights into the diagnosis, pathogenesis and therapeutic opportunities of IgG4-associated pleural effusion.


Assuntos
Imunoglobulina G/metabolismo , Inflamação/imunologia , Pulmão/metabolismo , Plasmócitos/imunologia , Derrame Pleural/imunologia , Adulto , Idoso , Movimento Celular , Feminino , Fibrose , Seguimentos , Humanos , Cadeias Pesadas de Imunoglobulinas/metabolismo , Cadeias Leves de Imunoglobulina/metabolismo , Imuno-Histoquímica , Japão , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Derrame Pleural/diagnóstico , Estudos Retrospectivos , Adulto Jovem
6.
Nanotechnology ; 28(38): 385301, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28699622

RESUMO

Ion implantation through nanometer-scale apertures (nano-apertures) is a promising method to precisely position ions in silicon matrices, which is a requirement for next generation electronic and quantum computing devices. This paper reports the application of atom probe tomography (APT) to investigate the three-dimensional distribution of germanium atoms in silicon after implantation through nano-aperture of 10 nm in diameter, for evaluation of the amount and spatial distribution of implanted dopants. The experimental results obtained by APT are consistent with a simple simulation with consideration of several effects during lithography and ion implantation, such as channeling and resist flow.

7.
Nutr Metab Cardiovasc Dis ; 26(9): 808-14, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27212620

RESUMO

BACKGROUND AND AIMS: Findings of observational studies suggest cardioprotective effects of antioxidant vitamins and carotenoids. However, recent meta-analyses failed to show the beneficial effects of supplemental intake of antioxidants on cardiovascular disease (CVD). We aimed to assess the association between CVD risk and ß-cryptoxanthin in Japan, where Satsuma mandarin, a major source of ß-cryptoxanthin, is widely consumed. METHODS AND RESULTS: This was part of the Mikkabi cohort study. Surveys were conducted at baseline, in 2003 and 2005, and on follow-up in 2006, 2009, and 2013. We examined brachial-ankle pulse wave velocity (baPWV) with a high cut-off value set at 18.3 m s(-1). Hazard ratios (HR) and 95% confidence intervals for high baPWV were estimated using a Cox proportional hazards model with adjustment for potential confounders. A total of 635 participants with baPWV of less than 18.3 m s(-1) at baseline were included in the analysis. During the follow-up period of 57,921 person-months, 99 subjects developed high baPWV. After multivariate adjustment, the HR for high baPWV in the highest tertile compared with the lowest tertile was significantly low for ß-cryptoxanthin, ß-carotene, and total carotenoids. Serum concentrations of ß-cryptoxanthin and ß-carotene were higher in people who ate Satsuma mandarin frequently. Compared with <1/d intake of Satsuma mandarin, 3-4/d was associated with a low risk of high PWV. CONCLUSION: This study indicated that ß-cryptoxanthin and ß-carotene derived from Satsuma mandarin are candidate micronutrients for preventing arteriosclerosis development. Further longitudinal and interventional studies will be required to validate the effect on CVD.


Assuntos
Índice Tornozelo-Braço , Arteriosclerose/prevenção & controle , beta-Criptoxantina/sangue , Citrus , Dieta Saudável , Frutas , Análise de Onda de Pulso , beta Caroteno/sangue , Adulto , Idoso , Arteriosclerose/sangue , Arteriosclerose/diagnóstico , Arteriosclerose/fisiopatologia , beta-Criptoxantina/administração & dosagem , Feminino , Inquéritos Epidemiológicos , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Fatores de Risco , Comportamento de Redução do Risco , Fatores de Tempo , beta Caroteno/administração & dosagem
8.
Br J Surg ; 102(7): 776-84, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25847111

RESUMO

BACKGROUND: The optimal surgical resection method in patients with HCC to minimize the risk of local recurrence has not yet been determined. The aim of this study was to compare the prognosis following anatomical versus non-anatomical hepatic resection for hepatocellular carcinoma (HCC). METHODS: Consecutive patients with HCC without macroscopic vascular invasion, treated by curative resection between 1981 and 2012 at Osaka Medical Centre, were included in this retrospective study. The outcomes of patients selected by propensity score matching were compared. RESULTS: Some 1102 patients were included, 577 in the anatomical and 525 in the non-anatomical resection group. By propensity score matching, 329 patients were selected into each group. Demographic, preoperative and tumour variables were similar between the propensity score-matched groups, including tumour size, tumour multiplicity, α-fetoprotein level and 15-min indocyanine green retention rate at 15 min. The incidence of microvascular invasion was higher in the matched anatomical resection group (P = 0·048). Stratified analysis of recurrence-free and overall survival rates revealed no statistically significant differences between the two propensity score-matched groups (P = 0·704 and P = 0·381 respectively). There was also no significant difference in the early recurrence rate within 2 years after resection between these groups (P = 0·726). Subset analysis of the early recurrence-free survival rate in patients with and without microvascular invasion revealed no significant differences between the groups (P = 0·312 and P = 0·479 respectively). CONCLUSION: The resection method had no impact on the risk of HCC recurrence or survival.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia/métodos , Neoplasias Hepáticas/cirurgia , Fígado/anatomia & histologia , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/mortalidade , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Incidência , Japão/epidemiologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Pontuação de Propensão , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento
9.
Theor Appl Genet ; 128(4): 769-78, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25687128

RESUMO

KEY MESSAGE: We fine-mapped a quantitative trait locus, qLG - 9, for seed longevity detected between Japonica-type and Indica-type cultivars. qLG - 9 was mapped in a 30-kb interval of the Nipponbare genome sequence. A quantitative trait locus, qLG-9, for seed longevity in rice has previously been detected on chromosome 9 by using backcross inbred lines derived from a cross between Japonica-type (Nipponbare) and Indica-type (Kasalath) cultivars. In the present study, the chromosomal location of qLG-9 was precisely determined by fine-scale mapping. Firstly, allelic difference in qLG-9 was verified by QTL analysis of an F2 population derived from a cross between Nipponbare and NKSL-1, in which a segment of Kasalath chromosome 9 was substituted in Nipponbare genetic background. Then, we selected F2 plants in which recombination had occurred near qLG-9 and performed F3 progeny testing on these plants to determine the genotype classes of qLG-9. Eventually, qLG-9 was mapped in a 30-kb interval (defined by two markers, CAPSb and CHPa12) of the Nipponbare genome sequence. This allowed us to nominate positional candidate genes of qLG-9. Additionally, we developed near-isogenic lines (NIL) for qLG-9 by marker-assisted selection. qLG-9 NIL showed significantly higher seed longevity than isogenic control of Nipponbare. These results will facilitate cloning of the gene(s) underlying qLG-9 as well as marker-assisted transfer of desirable genes for seed longevity improvement in rice.


Assuntos
Mapeamento Cromossômico , Oryza/genética , Locos de Características Quantitativas , Sementes/crescimento & desenvolvimento , Cromossomos de Plantas , Cruzamentos Genéticos , Ligação Genética , Marcadores Genéticos , Genótipo , Polimorfismo de Fragmento de Restrição , Sitios de Sequências Rotuladas
10.
Gynecol Oncol ; 137(2): 299-305, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25541259

RESUMO

OBJECTIVE: In ovarian cancer cases, recurrence after chemotherapy is frequently observed, suggesting the involvement of ovarian cancer stem-like cells (CSCs). The chemoresistance of ovarian clear cell carcinomas is particularly strong in comparison to other epithelial ovarian cancer subtypes. We investigated the relationship between a CSC marker, aldehyde dehydrogenase 1 (ALDH1), and clinical prognosis using ovarian clear cell carcinoma tissue samples. Furthermore, we investigated the antioxidant mechanism by which CSCs maintain a lower reactive oxygen species (ROS) level, which provides protection from chemotherapeutic agents. METHODS: Immunohistochemical staining was performed to examine the CSC markers (CD133, CD44, ALDH1) using ovarian clear cell carcinoma tissue samples (n=81). Clear cell carcinoma cell lines (KOC-7C, OVTOKO) are separated into the ALDH-high and ALDH-low populations by ALDEFLUOR assay and fluorescence-activated cell sorting (FACS). We compared the intracellular ROS level, mRNA level of the antioxidant enzymes and Nrf2 expression of the two populations. RESULTS: High ALDH1 expression levels are related to advanced stage in clear cell carcinoma cases. ALDH1 expression significantly reduced progression free survival. Other markers are not related to clinical stage and prognosis. ALDH-high cells contained a lower ROS level than ALDH-low cells. Antioxidant enzymes were upregulated in ALDH-high cells. ALDH-high cells showed increased expression of Nrf2, a key transcriptional factor of the antioxidant system. CONCLUSIONS: ALDH-positive CSCs might have increased Nrf2-induced antioxidant scavengers, which lower ROS level relevant to chemoresistance in ovarian clear cell carcinoma.


Assuntos
Adenocarcinoma de Células Claras/metabolismo , Isoenzimas/metabolismo , Neoplasias Epiteliais e Glandulares/metabolismo , Células-Tronco Neoplásicas/metabolismo , Neoplasias Ovarianas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Retinal Desidrogenase/metabolismo , Adenocarcinoma de Células Claras/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Família Aldeído Desidrogenase 1 , Carcinoma Epitelial do Ovário , Linhagem Celular Tumoral , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/patologia , Células-Tronco Neoplásicas/enzimologia , Células-Tronco Neoplásicas/patologia , Neoplasias Ovarianas/patologia , Prognóstico
11.
Arch Virol ; 160(1): 225-34, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25385175

RESUMO

Multiorgan failure with vascular hyperpermeability is the final outcome in the progression of seasonal influenza virus pneumonia and influenza-associated encephalopathy, and it is also common in infection with highly pathogenic avian influenza virus. However, the precise molecular mechanism by which influenza virus infection causes vascular endothelial cell hyperpermeability remains poorly defined. We investigated the mechanisms of hyperpermeability of human umbilical vein endothelial cells infected with influenza A virus (IAV)/Puerto Rico/8/34 (PR8) (H1N1). The levels of ß-catenin, a key regulatory component of the vascular endothelial-cadherin cell adhesion complex, were markedly decreased during infection for 28 h, with increments of vascular hyperpermeability measured by transendothelial electrical resistance. Lactacystin (at 2 µM), a proteasome inhibitor, inhibited the decrease in ß-catenin levels. Since the N-terminal phosphorylation of ß-catenin by glycogen synthase kinase (GSK)-3ß is the initiation step of proteasome-dependent degradation, we examined the effects of GSK-3ß suppression by RNA interference in endothelial cells. IAV-infection-induced ß-catenin degradation was significantly inhibited in GSK-3ß-knockdown cells, and transfection of cells with recombinant ß-catenin significantly suppressed IAV-induced hyperpermeability. These findings suggest that IAV infection induces GSK-3ß-mediated ß-catenin degradation in the adherens junctional complexes and induces vascular hyperpermeability. The in vitro findings of ß-catenin degradation and activation of GSK-3ß after IAV infection were confirmed in lungs of mice infected with IAV PR8 during the course of infection from day 0 to day 6. These results suggest that GSK-3ß-mediated ß-catenin degradation in adherens junctions is one of the key mechanisms of vascular hyperpermeability in severe influenza.


Assuntos
Junções Aderentes/fisiologia , Membrana Celular/fisiologia , Células Endoteliais/virologia , Quinase 3 da Glicogênio Sintase/metabolismo , Vírus da Influenza A Subtipo H1N1/fisiologia , beta Catenina/metabolismo , Animais , Células Cultivadas , Feminino , Inativação Gênica , Quinase 3 da Glicogênio Sintase/genética , Glicogênio Sintase Quinase 3 beta , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Permeabilidade , beta Catenina/genética
12.
West Indian Med J ; 65(2): 291-294, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-28358447

RESUMO

AIM: To study the frequency of congenital cytomegalovirus (CMV) infection in newborns admitted to the Division of Neonatology, using nested polymerase chain reaction (PCR) and DNA to detect differences in blood and urine specimens. METHODS: The study was carried out for eight months. Newborns (n = 520) hospitalized in five hospitals in Campo Grande, Mato Grosso do Sul, Brazil, were checked for CMV by analysing blood and urine samples. RESULTS: Cytomegalovirus was PCR positive in 13 urine and 10 blood samples. Of the 13 positive urine patients, three (23%) had no clinical signs suggestive of CMV, and another three (23%) patients admitted to the neonatal intensive care unit (NICU) had no definite findings of bacterial infection, with negative blood culture and some clinical signs consistent with CMV as cholestasis, hepatomegaly and eosinophilia. Three patients were on mechanical ventilation and showed improvement after prescription of ganciclovir. One CMV positive child progressed to death. CONCLUSION: Cytomegalovirus detection in urine was slightly more efficient than in blood, and showed better sensitivity than in serological analysis (p < 0.01) therefore, boiled urine may be a better and easier specimen tool for CMV diagnosis in neonatal infection. The findings of the present research suggest that patients admitted to the NICU, especially premature infants, whose laboratory results are not compatible with bacterial infection, and exhibiting signs suggestive of CMV infection should have PCR done on urine for confirmation.

13.
J Chem Phys ; 141(3): 034708, 2014 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-25053335

RESUMO

Adsorptions of alkali metals (such as K and Li) on monolayers of coronene and picene realize the formation of ordered phases, which serve as well-defined model systems for metal-intercalated aromatic superconductors. Upon alkali-doping of the monolayers of coronene and picene, scanning tunneling microscopy and X-ray absorption spectroscopy revealed the rearrangement of the entire molecular layer. The K-induced reconstruction of both monolayers resulted in the formation of a structure with a herringbone-like arrangement of molecules, suggesting the intercalation of alkali metals between molecular planes. Upon reconstruction, a shift in both the vacuum level and core levels of coronene was observed as a result of a charge transfer from alkali metals to coronene. In addition, a new density of states near the Fermi level was formed in both the doped coronene and the doped picene monolayers. This characteristic electronic feature of the ordered monolayer has been also reported in the multilayer picene films, ensuring that the present monolayer can model the properties of the metal-intercalated aromatic hydrocarbons. It is suggested that the electronic structure near the Fermi level is sensitive to the molecular arrangement, and that both the strict control and determinations of the molecular structure in the doped phase should be important for the determination of the electronic structure of these materials.

14.
Nucleic Acids Res ; 40(11): 5101-14, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22344691

RESUMO

Poly-C-binding proteins are triple KH (hnRNP K homology) domain proteins with specificity for single stranded C-rich RNA and DNA. They play diverse roles in the regulation of protein expression at both transcriptional and translational levels. Here, we analyse the contributions of individual αCP1 KH domains to binding C-rich oligonucleotides using biophysical and structural methods. Using surface plasmon resonance (SPR), we demonstrate that KH1 makes the most stable interactions with both RNA and DNA, KH3 binds with intermediate affinity and KH2 only interacts detectibly with DNA. The crystal structure of KH1 bound to a 5'-CCCTCCCT-3' DNA sequence shows a 2:1 protein:DNA stoichiometry and demonstrates a molecular arrangement of KH domains bound to immediately adjacent oligonucleotide target sites. SPR experiments, with a series of poly-C-sequences reveals that cytosine is preferred at all four positions in the oligonucleotide binding cleft and that a C-tetrad binds KH1 with 10 times higher affinity than a C-triplet. The basis for this high affinity interaction is finally detailed with the structure determination of a KH1.W.C54S mutant bound to 5'-ACCCCA-3' DNA sequence. Together, these data establish the lead role of KH1 in oligonucleotide binding by αCP1 and reveal the molecular basis of its specificity for a C-rich tetrad.


Assuntos
Citosina/química , Ribonucleoproteínas Nucleares Heterogêneas/química , Oligonucleotídeos/química , Sítios de Ligação , DNA/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Modelos Moleculares , Ligação Proteica , Estrutura Terciária de Proteína , RNA Mensageiro/química , RNA Mensageiro/metabolismo
15.
Theor Appl Genet ; 126(9): 2417-25, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23797600

RESUMO

Bacterial seedling rot (BSR), a destructive disease of rice (Oryza sativa L.), is caused by the bacterial pathogen Burkholderia glumae. To identify QTLs for resistance to BSR, we conducted a QTL analysis using chromosome segment substitution lines (CSSLs) derived from a cross between Nona Bokra (resistant) and Koshihikari (susceptible). Comparison of the levels of BSR in the CSSLs and their recurrent parent, Koshihikari, revealed that a region on chromosome 10 was associated with resistance. Further genetic analyses using an F5 population derived from a cross between a resistant CSSL and Koshihikari confirmed that a QTL for BSR resistance was located on the short arm of chromosome 10. The Nona Bokra allele was associated with resistance to BSR. Substitution mapping in the Koshihikari genetic background demonstrated that the QTL, here designated as qRBS1 (quantitative trait locus for RESISTANCE TO BACTERIAL SEEDLING ROT 1), was located in a 393-kb interval (based on the Nipponbare reference genome sequence) defined by simple sequence repeat markers RM24930 and RM24944.


Assuntos
Resistência à Doença/genética , Oryza/genética , Locos de Características Quantitativas , Plântula/genética , Alelos , Burkholderia/patogenicidade , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Cruzamentos Genéticos , DNA de Plantas/genética , Ligação Genética , Marcadores Genéticos , Repetições de Microssatélites , Oryza/microbiologia , Fenótipo , Plântula/microbiologia
16.
RNA Biol ; 10(4): 579-89, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23603827

RESUMO

The RNA-binding protein TIAR is an mRNA-binding protein that acts as a translational repressor, particularly important under conditions of cellular stress. It binds to target mRNA and DNA via its RNA recognition motif (RRM) domains and is involved in both splicing regulation and translational repression via the formation of "stress granules." TIAR has also been shown to bind ssDNA and play a role in the regulation of transcription. Here we show, using surface plasmon resonance and nuclear magnetic resonance spectroscopy, specific roles of individual TIAR domains for high-affinity binding to RNA and DNA targets. We confirm that RRM2 of TIAR is the major RNA- and DNA-binding domain. However, the strong nanomolar affinity binding to U-rich RNA and T-rich DNA depends on the presence of the six amino acid residues found in the linker region C-terminal to RRM2. On its own, RRM1 shows preferred binding to DNA over RNA. We further characterize the interaction between RRM2 with the C-terminal extension and an AU-rich target RNA sequence using NMR spectroscopy to identify the amino acid residues involved in binding. We demonstrate that TIAR RRM2, together with its C-terminal extension, is the major contributor for the high-affinity (nM) interactions of TIAR with target RNA sequences.


Assuntos
Motivos de Aminoácidos , Proteínas de Ligação a DNA/metabolismo , DNA/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , DNA/genética , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Ligação Proteica , Splicing de RNA , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Alinhamento de Sequência , Ressonância de Plasmônio de Superfície
17.
Nucleic Acids Res ; 39(3): 1117-30, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21233170

RESUMO

TIAR and HuR are mRNA-binding proteins that play important roles in the regulation of translation. They both possess three RNA recognition motifs (RRMs) and bind to AU-rich elements (AREs), with seemingly overlapping specificity. Here we show using SPR that TIAR and HuR bind to both U-rich and AU-rich RNA in the nanomolar range, with higher overall affinity for U-rich RNA. However, the higher affinity for U-rich sequences is mainly due to faster association with U-rich RNA, which we propose is a reflection of the higher probability of association. Differences between TIAR and HuR are observed in their modes of binding to RNA. TIAR is able to bind deoxy-oligonucleotides with nanomolar affinity, whereas HuR affinity is reduced to a micromolar level. Studies with U-rich DNA reveal that TIAR binding depends less on the 2'-hydroxyl group of RNA than HuR binding. Finally we show that SAXS data, recorded for the first two domains of TIAR in complex with RNA, are more consistent with a flexible, elongated shape and not the compact shape that the first two domains of Hu proteins adopt upon binding to RNA. We thus propose that these triple-RRM proteins, which compete for the same binding sites in cells, interact with their targets in fundamentally different ways.


Assuntos
Antígenos de Superfície/química , DNA/química , Proteínas de Ligação a RNA/química , RNA/química , Adenina/análise , Antígenos de Superfície/metabolismo , DNA/metabolismo , Proteínas ELAV , Proteína Semelhante a ELAV 1 , Cinética , Modelos Moleculares , Ligação Proteica , Conformação Proteica , RNA/metabolismo , Proteínas de Ligação a RNA/metabolismo , Espalhamento a Baixo Ângulo , Uracila/análise , Difração de Raios X
18.
J Frailty Aging ; 12(1): 30-36, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36629081

RESUMO

OBJECTIVES: This study aimed to investigate the influences of living arrangements on the association between dietary variety and frailty by gender in community-dwelling older people. DESIGN: A cross-sectional study. SETTING: Nishinomiya city, Hyogo prefecture, Japan. PARTICIPANTS: A total of 4,996 randomly selected community-dwelling older people aged 65 years and older and living in Nishinomiya City. MEASUREMENTS: Survey questionnaires were distributed via mail. The frailty score was evaluated by the 5-item frailty screening index. Dietary variety was assessed using the dietary variety score developed for the general older Japanese population. RESULTS: A total of 2,764 community-dwelling participants aged ≥ 65 years responded to the questionnaires. After excluding missing data, 1,780 participants were included in the study analysis. The frailty scores in older men living alone were significantly higher than those in older men living with someone (P < 0.001). The dietary variety scores in older men living alone were significantly lower than those in older men living with someone (P < 0.001). However, differences in the frailty and dietary variety scores between living alone and living with someone were not were observed in older women (P = 0.360 and P = 0.265, respectively). In the multivariable regression analysis, the associations between dietary variety score and frailty score in living alone (ß= -0. 271, P = 0.011) were stronger than those in living with someone in the case of older men (ß= -0.131, P = 0.045). Similar associations between dietary variety and frailty were presented in older women living alone than in those living with someone (ß -0.114, P = 0.002; ß -0.088, P = 0.012, respectively). CONCLUSIONS: Older men who live alone had higher frailty score and lower dietary variety. The associations between dietary variety and frailty were different according to living arrangements in both older men and older women.


Assuntos
Fragilidade , Masculino , Humanos , Feminino , Idoso , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Vida Independente , Estudos Transversais , Fatores Sexuais , Comportamento Alimentar
19.
Theor Appl Genet ; 125(3): 551-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22446930

RESUMO

Quantitative trait loci (QTLs) for resistance to rice blast offer a potential source of durable disease resistance in rice. However, few QTLs have been validated in progeny testing, on account of their small phenotypic effects. To understand the genetic basis for QTL-mediated resistance to blast, we dissected a resistance QTL, qBR4-2, using advanced backcross progeny derived from a chromosome segment substitution line in which a 30- to 34-Mb region of chromosome 4 from the resistant cultivar Owarihatamochi was substituted into the genetic background of the highly susceptible Aichiasahi. The analysis resolved qBR4-2 into three loci, designated qBR4-2a, qBR4-2b, and qBR4-2c. The sequences of qBR4-2a and qBR4-2b, which lie 181 kb apart from each other and measure, 113 and 32 kb, respectively, appear to encode proteins with a putative nucleotide-binding site (NBS) and leucine-rich repeats (LRRs). Sequence analysis of the donor allele of qBR4-2a, the region with the largest effect among the three, revealed sequence variations in the NBS-LRR region. The effect of qBR4-2c was smallest among the three, but its combination with the donor alleles of qBR4-2a and qBR4-2b significantly enhanced blast resistance. qBR4-2 comprises three tightly linked QTLs that control blast resistance in a complex manner, and thus gene pyramiding or haplotype selection is the recommended strategy for improving QTL-mediated resistance to blast disease through the use of this chromosomal region.


Assuntos
Cromossomos de Plantas/genética , Genes de Plantas , Oryza/genética , Doenças das Plantas/genética , Alelos , Mapeamento Cromossômico , Cruzamentos Genéticos , Resistência à Doença/genética , Ligação Genética , Oryza/imunologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Análise de Sequência de DNA
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