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1.
Acta Neurol Scand ; 135(2): 197-203, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26932875

RESUMO

OBJECTIVE: We conducted a cohort study to investigate whether benign paroxysmal positional vertigo (BPPV) is correlated with an increased risk of dementia. METHODS: We established a case cohort comprising 7818 patients aged over 20 years who were diagnosed with BPPV from 2000 to 2010. In addition, we formed a control cohort by randomly selecting 31,272 people without BPPV and matched them with the BPPV patients according to gender, age, and index year. Cox proportional hazard regressions were performed to compute the hazard ratio (HR) of dementia after we adjusted for demographic characteristics and comorbidity. RESULTS: The prevalence of comorbidity was higher among patients with BPPV than among those without BPPV. In addition, patients with BPPV exhibited a 1.24-fold (95% confidence interval, CI 1.09-1.40; P < 0.001) higher risk of dementia than those without BPPV after we adjusted for age, gender, and comorbidity. An analysis stratified according to demographic factors revealed that women with BPPV exhibited a 1.36-fold (95% CI 1.16-1.59; P < 0.001) higher risk of dementia. Patients with BPPV aged over 65 years exhibited a significantly higher risk of dementia (adjusted HR: 1.26; 95% CI 1.10-1.43; P < 0.001) than those without BPPV. CONCLUSIONS: Patients with BPPV exhibited a higher risk of dementia than those without BPPV.


Assuntos
Vertigem Posicional Paroxística Benigna/diagnóstico , Vertigem Posicional Paroxística Benigna/epidemiologia , Demência/diagnóstico , Demência/epidemiologia , Adulto , Idoso , Estudos de Coortes , Comorbidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Distribuição Aleatória
2.
Ann Oncol ; 24(6): 1491-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23406736

RESUMO

BACKGROUND: Bone marrow-derived endothelial progenitor cells (EPCs) are critical for metastatic progression. This study explores the effect of tetrathiomolybdate (TM), an anti-angiogenic copper chelator, on EPCs in patients at high risk for breast cancer recurrence. PATIENTS AND METHODS: This phase 2 study enrolled breast cancer patients with stage 3 and stage 4 without evidence of disease (NED), and stage 2 if triple-negative. TM 100 mg orally was administered to maintain ceruloplasmin <17 mg/dl for 2 years or until relapse. The primary end point was change in EPCs. RESULTS: Forty patients (28 stage 2/3, 12 stage 4 NED) were enrolled. Seventy-five percent patients achieved the copper depletion target by 1 month. Ninety-one percent of triple-negative patients copper-depleted compared with 41% luminal subtypes. In copper-depleted patients only, there was a significant reduction in EPCs/ml by 27 (P = 0.04). Six patients relapsed while on study, of which only one patient had EPCs maintained below baseline. The 10-month relapse-free survival was 85.0% (95% CI 74.6%-96.8%). Only grade 3/4 toxicity was hematologic: neutropenia (3.1% of cycles), febrile neutropenia (0.2%), and anemia (0.2%). CONCLUSIONS: TM is safe and appears to maintain EPCs below baseline in copper-depleted patients. TM may promote tumor dormancy and ultimately prevent relapse.


Assuntos
Neoplasias da Mama/sangue , Cobre/sangue , Células Endoteliais/metabolismo , Molibdênio/uso terapêutico , Recidiva Local de Neoplasia/prevenção & controle , Células-Tronco/metabolismo , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Quelantes/uso terapêutico , Células Endoteliais/efeitos dos fármacos , Feminino , Humanos , Pessoa de Meia-Idade , Molibdênio/farmacologia , Recidiva Local de Neoplasia/sangue , Fatores de Risco , Células-Tronco/efeitos dos fármacos
3.
Clin Exp Allergy ; 43(5): 535-43, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23600544

RESUMO

BACKGROUND: The biological mechanisms of how prenatal smoke exposure leading to atopic disorders remain to be addressed. Whether prenatal smoke exposure affects DNA methylation leading to atopic disorders is not clear. OBJECTIVE: As most children suffering from atopic dermatitis (AD) continue to develop asthma later in life, we explored whether prenatal smoke exposure induces cord blood DNA methylation. METHODS: Methylation differences associated with smoke exposure were screened by Illumina Infinium 27K methylation arrays for 14 children from the Taiwan birth panel study cohort initially. Information about development of atopic dermatitis (AD) and risk factors was collected. Cord blood cotinine levels were measured to represent prenatal smoke exposure. CpG loci that demonstrated a statistically significant difference in methylation were validated by methylation-dependent fragment separation (MDFS). Differential methylation in three genes (TSLP, GSTT1, and CYB5R3) was identified through the screen. RESULTS: Among these, only thymic stromal lymphopoietin (TSLP) gene displayed significant difference in promoter methylation percentage after being validated by MDFS (p = 0.018). TSLP gene was further investigated in a larger sample of 150 children from the cohort who completed the follow-up study. Methylation status of the TSLP 5'-CpG island (CGI) was found to be significantly associated with prenatal smoke exposure (OR = 3.17, 95% CI = 1.63-6.19) and with AD (OR = 2.32, 95% CI = 1.06-5.11). The degree of TSLP 5'CGI methylation inversely correlated with TSLP protein expression levels (r = -0.45, P = 0.001). CONCLUSIONS & CLINICAL RELEVANCE: The effect of prenatal tobacco smoke exposure on the risk for AD may be mediated through DNA methylation.


Assuntos
Metilação de DNA , Dermatite Atópica/etiologia , Efeitos Tardios da Exposição Pré-Natal , Fumar/efeitos adversos , Criança , Ilhas de CpG , Citocromo-B(5) Redutase/genética , Citocinas/genética , Feminino , Glutationa Transferase/genética , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Gravidez , Regiões Promotoras Genéticas , Curva ROC , Fatores de Risco , Linfopoietina do Estroma do Timo
4.
Genes Immun ; 13(3): 214-20, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22048455

RESUMO

The etiology of systemic lupus erythematosus (SLE) involves a complex interaction of genetic and environmental factors. Investigations have shown that environmentally driven epigenetic changes contribute to the etiology of SLE. Here, we hypothesize that aberrant DNA methylation may contribute to the activation of the immune machinery and trigger lupus disease activity. A whole genome methylation array was applied to investigate the DNA methylation changes between 12 pairs of active SLE patients and healthy controls. The results were further confirmed in 66 SLE patients, 102 healthy controls. The methylation statuses of the IL10 and IL1R2 genes were significantly reduced in the SLE patient samples relative to the healthy controls (age-adjusted odds ratios, 64.2 and 16.9, respectively, P<0.0001). There was a trend toward SLE patients having hypomethylated IL10 and IL1R2 genes accompanied by greater disease activity. We observed that the methylation degree of IL10 and IL1R2 genes were reduced in the rheumatoid arthritis (RA) patients as well but the hypomethylation change was more significant in IL1R2 genes than in the IL10 genes in RA patients. This study demonstrated that DNA hypomethylation might be associated with SLE. Hypomethylated IL10 and IL1R2 genes may provide potential epigenetic markers as clinical predictors for autoimmune diseases.


Assuntos
Metilação de DNA , Genoma Humano , Interleucina-10/genética , Lúpus Eritematoso Sistêmico/genética , Regiões Promotoras Genéticas , Receptores Tipo II de Interleucina-1/genética , Artrite Reumatoide/genética , Artrite Reumatoide/imunologia , Epigênese Genética , Redes Reguladoras de Genes , Humanos , Interleucina-10/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Receptores Tipo II de Interleucina-1/imunologia
5.
Breast Cancer Res Treat ; 132(3): 1063-72, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22200869

RESUMO

In preclinical models, the histone deacetylase inhibitor vorinostat sensitizes breast cancer cells to tubulin-polymerizing agents and to anti-vascular endothelial growth factor-directed therapies. We sought to determine the safety and efficacy of vorinostat plus paclitaxel and bevacizumab as first-line therapy in metastatic breast cancer (MBC), and the biological effects of vorinostat in vivo. For this purpose of this study, 54 patients with measurable disease and no prior chemotherapy for MBC received vorinostat (200 or 300 mg PO BID) on days 1-3, 8-10, and 15-17, plus paclitaxel (90 mg/m(2)) on days 2, 9, 16, and bevacizumab (10 mg/kg) on days 2 and 16 every 28 days. The primary objective of the phase I study was to determine the recommended phase II dose (RPTD) of vorinostat, and for the phase II to detect an improvement of response rate from 40 to 60% (alpha = 0.10, beta = 0.10). No dose limiting toxicities were observed, and the RPTD of vorinostat was 300 mg BID. For the primary efficacy analysis in 44 patients at the RPTD, we observed 24 objective responses (55%, 95% confidence intervals (C.I) 39%, 70%). The adverse event profile was consistent with paclitaxel-bevacizumab, with the exception of increased diarrhea with the addition of vorinostat. Analysis of serial tumor biopsies in seven patients showed increased acetylation of Hsp90 and α-tubulin following vorinostat. Vorinostat induces histone and alpha tubulin acetylation and functional inhibition of Hsp90 in breast cancer in vivo and can be safely combined with paclitaxel and bevacizumab.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Tubulina (Proteína)/metabolismo , Acetilação , Adulto , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Bevacizumab , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Feminino , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Ácidos Hidroxâmicos/administração & dosagem , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Resultado do Tratamento , Vorinostat
6.
J Community Health ; 37(4): 763-72, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22109386

RESUMO

Employment status is related to treatment recovery and quality of life in breast cancer survivors, yet little is known about return to work in immigrant and minority survivors. We conducted an exploratory qualitative study using ethnically cohesive focus groups of urban breast cancer survivors who were African-American, African-Caribbean, Chinese, Filipina, Latina, or non-Latina white. We audio- and video-recorded, transcribed, and thematically coded the focus group discussions and we analyzed the coded transcripts within and across ethnic groups. Seven major themes emerged related to the participants' work experiences after diagnosis: normalcy, acceptance, identity, appearance, privacy, lack of flexibility at work, and employer support. Maintaining a sense of normalcy was cited as a benefit of working by survivors in each group. Acceptance of the cancer diagnosis was most common in the Chinese group and in participants who had a family history of breast cancer; those who described this attitude were likely to continue working throughout the treatment period. Appearance was important among all but the Chinese group and was related to privacy, which many thought was necessary to derive the benefit of normalcy at work. Employer support included schedule flexibility, medical confidentiality, and help maintaining a normal work environment, which was particularly important to our study sample. Overall, we found few differences between the different ethnic groups in our study. These results have important implications for the provision of support services to and clinical management of employed women with breast cancer, as well as for further large-scale research in disparities and employment outcomes.


Assuntos
Neoplasias da Mama/etnologia , Emigrantes e Imigrantes/psicologia , Emprego/psicologia , Grupos Minoritários/psicologia , Sobreviventes/psicologia , População Urbana , Adaptação Psicológica , Adulto , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/psicologia , Emigrantes e Imigrantes/estatística & dados numéricos , Emprego/estatística & dados numéricos , Etnicidade/psicologia , Etnicidade/estatística & dados numéricos , Feminino , Grupos Focais , Humanos , Relações Interprofissionais , Pessoa de Meia-Idade , Grupos Minoritários/estatística & dados numéricos , Pesquisa Qualitativa , Sobreviventes/estatística & dados numéricos , População Urbana/estatística & dados numéricos
7.
Ann Oncol ; 21(7): 1436-1441, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20032126

RESUMO

BACKGROUND: Sunitinib has shown single-agent activity in patients with previously treated metastatic breast cancer (MBC). We investigated the safety of the combination of sunitinib and paclitaxel in an exploratory study of patients with locally advanced or MBC. METHODS: Patients received oral sunitinib 25 mg/day (with escalation to 37.5 mg/day as tolerated) on a continuous daily dosing schedule and paclitaxel 90 mg/m(2) on days 1, 8, and 15 of each 28-day cycle. Study endpoints included safety (primary endpoint), pharmacokinetics, and antitumor activity. RESULTS: Twenty-two patients were enrolled. The most frequent adverse events (AEs) were fatigue/asthenia (77%), dysgeusia (68%), and diarrhea (64%). Grade 3 AEs included neutropenia (43%), fatigue/asthenia (27%), neuropathy (18%), and diarrhea (14%). No drug-drug interaction was observed on the basis of pharmacokinetic analysis. Of 18 patients with measurable disease at baseline, 7 (38.9%) achieved objective responses (including 2 complete and 5 partial responses). Clinical responses were observed in three of nine patients with triple-negative receptor status (estrogen receptor negative, progesterone receptor negative, and human epidermal growth factor receptor-2 negative). CONCLUSIONS: These data indicate that sunitinib and paclitaxel in combination are well tolerated in patients with locally advanced or MBC. No drug-drug interaction was detected and there was preliminary evidence of antitumor activity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Carcinoma Ductal de Mama/tratamento farmacológico , Carcinoma Lobular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Feminino , Humanos , Indóis/administração & dosagem , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Metástase Linfática , Dose Máxima Tolerável , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Projetos Piloto , Pirróis/administração & dosagem , Sunitinibe , Taxa de Sobrevida , Distribuição Tecidual , Resultado do Tratamento
8.
Ann Oncol ; 21(10): 2075-2080, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20357034

RESUMO

BACKGROUND: Ixabepilone is a semisynthetic epothilone B analogue that is active in taxane-resistant cell lines and has shown activity in patients with refractory breast and ovarian cancer. We carried out a phase I trial of ixabepilone plus pegylated liposomal doxorubicin (PLD) in patients with advanced taxane-pretreated ovarian and breast cancer. METHODS: Patients with recurrent ovarian or breast carcinoma received PLD every 3 or 4 weeks plus five different dose schemas of ixabepilone in cohorts of three to six patients. RESULTS: Thirty patients received a total of 142 treatment cycles of the PLD-ixabepilone combination. The recommended phase II dose and schedule of ixabepilone was 16 mg/m(2) on days 1, 8, and 15 plus PLD 30 mg/m(2) given on day 1, repeated every 4 weeks. Hand-foot syndrome and mucositis were dose limiting when both ixabepilone and PLD were given every 3 or 4 weeks. Objective responses were observed in 3 of 13 patients (23%) with breast cancer and 5 of 17 patients (29%) with ovarian cancer. CONCLUSION: Ixabepilone may be safely combined with PLD, but tolerability is highly dependent upon the scheduling of both agents. This combination demonstrated efficacy in patients with breast and ovarian cancer and merits further evaluation in these settings.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adulto , Idoso , Neoplasias da Mama/patologia , Hidrocarbonetos Aromáticos com Pontes/administração & dosagem , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Epotilonas/administração & dosagem , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/patologia , Polietilenoglicóis/administração & dosagem , Taxa de Sobrevida , Taxoides/administração & dosagem , Resultado do Tratamento
9.
Science ; 282(5397): 2263-6, 1998 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-9856951

RESUMO

CTLA-4, a negative regulator of T cell function, was found to associate with the T cell receptor (TCR) complex zeta chain in primary T cells. The association of TCRzeta with CTLA-4, reconstituted in 293 transfectants, was enhanced by p56(lck)-induced tyrosine phosphorylation. Coexpression of the CTLA-4-associated tyrosine phosphatase, SHP-2, resulted in dephosphorylation of TCRzeta bound to CTLA-4 and abolished the p56(lck)-inducible TCRzeta-CTLA-4 interaction. Thus, CTLA-4 inhibits TCR signal transduction by binding to TCRzeta and inhibiting tyrosine phosphorylation after T cell activation. These findings have broad implications for the negative regulation of T cell function and T cell tolerance.


Assuntos
Antígenos de Diferenciação/metabolismo , Imunoconjugados , Ativação Linfocitária , Proteínas de Membrana/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais , Linfócitos T/imunologia , Abatacepte , Animais , Antígenos CD , Antígeno CTLA-4 , Linhagem Celular , Células Cultivadas , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/genética , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Modelos Imunológicos , Fosforilação , Fosfotirosina/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Proteína Tirosina Fosfatase não Receptora Tipo 6 , Proteínas Tirosina Fosfatases/genética , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Tirosina Fosfatases Contendo o Domínio SH2 , Transfecção , Domínios de Homologia de src
10.
Oncogene ; 25(4): 622-32, 2006 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-16247478

RESUMO

The p53 protein has been implicated in multiple cellular responses related to DNA damage. Alterations in any of these cellular responses could be related to increased genomic instability. Our previous study has shown that mutations in p53 lead to hypermutability to ionizing radiation. To investigate further how p53 is involved in regulating mutational processes, we used 8K cDNA microarrays to compare the patterns of gene expression among three closely related human cell lines with different p53 status including TK6 (wild-type p53), NH32 (p53-null), and WTK1 (mutant p53). Total RNA samples were collected at 1, 3, 6, 9, and 24 h after 10 Gy gamma-irradiation. Template-based clustering analysis of the gene expression over the time course showed that 464 genes are either up or downregulated by at least twofold following radiation treatment. In addition, cluster analyses of gene expression profiles among these three cell lines revealed distinct patterns. In TK6, 165 genes were upregulated, while 36 genes were downregulated. In contrast, in WTK1 75 genes were upregulated and 12 genes were downregulated. In NH32, only 54 genes were upregulated. Furthermore, we found several genes associated with DNA repair namely p53R2, DDB2, XPC, PCNA, BTG2, and MSH2 that were highly induced in TK6 compared to WTK1 and NH32. p53R2, which is regulated by the tumor suppressor p53, is a small subunit of ribonucleotide reductase. To determine whether it is involved in radiation-induced mutagenesis, p53R2 protein was inhibited by siRNA in TK6 cells and followed by 2 Gy radiation. The background mutation frequencies at the TK locus of siRNA-transfected TK6 cells were about three times higher than those seen in TK6 cells. The mutation frequencies of siRNA-transfected TK6 cells after 2 Gy radiation were significantly higher than the irradiated TK6 cells without p53R2 knock down. These results indicate that p53R2 was induced by p53 protein and is involved in protecting against radiation-induced mutagenesis.


Assuntos
Reparo do DNA , Mutação , Transcrição Gênica/efeitos da radiação , Proteína Supressora de Tumor p53/fisiologia , Células Cultivadas , Dano ao DNA , Expressão Gênica/efeitos da radiação , Perfilação da Expressão Gênica , Humanos , NF-kappa B/metabolismo , Fator de Crescimento Transformador beta/fisiologia , Fator de Crescimento Transformador beta1
11.
J Clin Invest ; 95(2): 832-41, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7860767

RESUMO

The regenerating liver after partial hepatectomy is one of the few physiologic models of cellular proliferation in the adult animal. During hepatic regeneration, the animal is able to maintain metabolic homeostasis despite the acute loss of two thirds of hepatic tissue. In examining the molecular mechanisms regulating hepatic regeneration, we isolated novel immediate-early genes that are rapidly induced as the remnant liver undergoes the transition from its normal quiescent state into the G1 phase of the cell cycle. One of the most rapidly and highly induced genes which we initially termed RL-1, encodes rat glucose-6-phosphatase (rG6Pase). G6Pase mRNA peaks at 30 min and 36-48 h after hepatectomy correlating with the first and second rounds of cell division. This finding is compatible with studies that showed that G6Pase enzyme activity increases during liver regeneration. However, the increase in G6Pase mRNA is much more dramatic, indicating that it is a more sensitive indicator of this regulation. G6Pase gene expression peaks in the perinatal time period in the liver and remains elevated during the first month of life. The expression of the G6Pase gene is also dramatically elevated in BB diabetic rats, again higher than the enzyme elevation, and its relative induction after partial hepatectomy is blunted in these animals. Insulin treatment of partially hepatectomized diabetic animals downregulates the expression of G6Pase mRNA. Using specific antibodies against G6Pase, we detect a 36-kD G6Pase protein, and its level is elevated in regenerating and diabetic livers. The pattern of G6Pase mRNA expression appears to reflect similar changes in insulin and glucagon levels which accompany diabetes and hepatic proliferation. The elevation of G6Pase expression in these conditions is indicative of its importance as a regulator of glucose homeostasis in normal and abnormal physiologic states.


Assuntos
Diabetes Mellitus Tipo 1/enzimologia , Expressão Gênica , Glucose-6-Fosfatase/biossíntese , Glucose-6-Fosfatase/genética , Regeneração Hepática , Fígado/enzimologia , Células 3T3 , Animais , Sequência de Bases , Glicemia/metabolismo , Northern Blotting , Ciclo Celular , Linhagem Celular , Primers do DNA , DNA Complementar , Fase G1 , Hepatectomia , Immunoblotting , Insulina/sangue , Fígado/citologia , Fígado/fisiologia , Neoplasias Hepáticas Experimentais , Camundongos , Dados de Sequência Molecular , Especificidade de Órgãos , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Ratos , Ratos Endogâmicos BB , Células Tumorais Cultivadas
12.
J Clin Invest ; 61(3): 633-9, 1978 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-641144

RESUMO

Studies were performed in Munich-Wistar rats to determine whether changes in papillary plasma flow might be responsible for the concentrating defect which occurs after exposure of the extrarenal papilla. Papillary plasma flow was measured by (125)I-albumin accumulation. Initial studies in hydropenic animals revealed that papillary plasma flow was 40% higher in the kidney with the exposured papilla, 41 vs. 29 ml/min per 100 g of papilla (P < 0.001). This increase in papillary plasma flow was detectable 15 or 45 min after removing the ureter. Because it was unclear whether the rise in papillary plasma flow was a cause or the result of the fall in urine osmolality, similar studies were performed in animals undergoing a water diuresis. In this setting, papillary plasma flow still increased on the exposed side compared to the control side, 81 vs. 60 ml/min per 100 g, despite similarly low urine osmolalities of 155 and 174 mosmol/kg, respectively. This finding is compatible with the possibility that papillary exposure per se causes an increase in papillary plasma flow and that this hemodynamic alteration may lead to a reduction in urinary osmolality secondary to washout of the medullary interstitium. A final group of hydropenic rats was given either indomethacin or meclofenamate before removing the ureter. In these studies, there was no difference in either the papillary plasma flow or the urine osmolality between control and exposed kidneys. It is therefore suggested that opening the ureter induces an increase in papillary plasma flow by some mechanism which may involve an alteration in prostaglandin synthesis.


Assuntos
Capacidade de Concentração Renal , Rim/fisiologia , Animais , Diurese , Indometacina/farmacologia , Rim/irrigação sanguínea , Rim/efeitos dos fármacos , Capacidade de Concentração Renal/efeitos dos fármacos , Ácido Meclofenâmico/farmacologia , Concentração Osmolar , Ratos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fatores de Tempo
13.
Mol Cell Biol ; 14(8): 5318-25, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8035810

RESUMO

Genetic and biochemical evidence suggests that the Ras protooncogene product regulates the activation of the Raf kinase pathway, leading to the proposal that Raf is a direct mitogenic effector of activated Ras. Here we report the use of a novel competition assay to measure in vitro the relative affinity of the c-Raf-1 regulatory region for Ras-GTP, Ras-GDP, and 10 oncogenic and effector mutant Ras proteins. c-Raf-1 associates with normal Ras and the oncogenic V12 and L61 forms of Ras with equal affinity. The moderately transforming mutant Ras[E30K31] also bound to the c-Raf-1 regulatory region with normal affinity. Transformation-defective Ras effector mutants Ras[N33], Ras[S35], and Ras[N38] bound poorly. In contrast, the transformation defective Ras[G26I27] and Ras[E45] mutants bound to the c-Raf-1 regulatory region with nearly wild-type affinity. A stable, high-affinity Ras-binding region of c-Raf-1 was mapped to a 99-amino-acid subfragment of the first 257 residues. The smallest Ras-binding region identified consisted of N-terminal residues 51 to 131, although stable expression of the domain and high-affinity binding were improved by the presence of residues 132 to 149. Deletion of the Raf zinc finger region did not reduce Ras-binding affinity, while removal of the first 50 amino acids greatly increased affinity. Phosphorylation of Raf[1-149] by protein kinase A on serine 43 resulted in significant inhibiton of Ras binding. demonstrating that the mechanism of cyclic AMP downregulation results through structural changes occurring exclusively in this small Ras-binding domain.


Assuntos
Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Guanosina Trifosfato/metabolismo , Mutagênese Sítio-Dirigida , Fosforilação , Fosfosserina/metabolismo , Ligação Proteica , Proteínas Proto-Oncogênicas c-raf , Proteínas Recombinantes de Fusão , Deleção de Sequência , Relação Estrutura-Atividade
14.
J Clin Transl Sci ; 1(1): 67-72, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28480057

RESUMO

INTRODUCTION: Interdisciplinary collaboration is a critical component of translation, dissemination, implementation, and improvement (TDII) science. Yet, little is known about effective frameworks and practices regarding interdisciplinary research in TDII. METHODS: This study drew on data collected from an expert panel during a regional symposium. RESULTS: Findings highlight facilitators and barriers to stimulating interdisciplinary TDII research in different domains: intrapersonal, interpersonal, organizational, power and hierarchy, physical environment, and communication and language. CONCLUSIONS: Findings have significant implications for TDII of clinical practices.

15.
Aliment Pharmacol Ther ; 23(10): 1415-25, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16669956

RESUMO

BACKGROUND: Alicaforsen is an antisense oligonucleotide designed to inhibit expression of human intercellular adhesion molecule 1. Previous clinical studies have demonstrated activity of alicaforsen enema in ulcerative colitis and pouchitis. AIM: To determine the minimally effective dosing regimen of alicaforsen enema in subjects with mild to moderate left-sided ulcerative colitis. METHODS: Randomized, placebo-controlled, double-blind, two-dose ranging multicentre study. One hundred and twelve subjects were equally randomized to receive one of four alicaforsen enema regimens or placebo daily for 6 weeks. Primary end point was Disease Activity Index at week 6. Secondary end points included evaluation of clinical improvement, relapse rates and durability of response. Analysis of data were performed on the intent-to-treat population. RESULTS: No significant difference was observed between treatment arms and placebo in the primary end point. A prolonged reduction in mean% Disease Activity Index relative to baseline was observed in the daily 240 mg alicaforsen enema treatment arm in comparison with placebo from week 18 (51% vs. 18%, P=0.04) to week 30 (50% vs. 11%, P=0.03). CONCLUSIONS: Alicaforsen enema was safe and well tolerated at all doses studied. The durability of the response to alicaforsen enema treatment may suggests a disease-modifying effect.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Fármacos Gastrointestinais/administração & dosagem , Oligodesoxirribonucleotídeos Antissenso/administração & dosagem , Tionucleotídeos/administração & dosagem , Adulto , Idoso , Método Duplo-Cego , Esquema de Medicação , Enema , Feminino , Fármacos Gastrointestinais/efeitos adversos , Hemorragia Gastrointestinal/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Oligodesoxirribonucleotídeos Antissenso/efeitos adversos , Oligonucleotídeos Fosforotioatos , Reto , Recidiva , Tionucleotídeos/efeitos adversos , Resultado do Tratamento
16.
Aliment Pharmacol Ther ; 23(10): 1427-34, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16669957

RESUMO

BACKGROUND: Alicaforsen is a phosphorothioate-modified antisense oligodeoxynucleotide designed to sequence-specifically reduce intercellular adhesion molecule 1 messenger RNA levels. AIMS: To determine the systemic and local bioavailability of alicaforsen, and its activity when administered as a once daily enema in subjects with active ulcerative colitis. METHODS An open-label study was conducted to assess the relative absorption (local and systemic pharmacokinetics) and pharmacologic activity of alicaforsen enema in subjects with active ulcerative colitis. Fifteen subjects received nightly enemas of alicaforsen (240 mg) for a treatment period of 6 weeks. Alicaforsen concentrations in plasma and colonic tissue biopsies were determined. Disease activity index and multiple measurements including endoscopy were used to assess alicaforsen activity in these subjects. RESULTS: Plasma concentrations of parent alicaforsen represented < 0.6% mean bioavailability when compared with historical intravenous area under the plasma concentration-time curves. Concentrations of the intact oligonucleotide in mucosal colonic tissue biopsies were orders of magnitude higher than those observed in plasma. A 46% reduction in mean Disease Activity Index and 33% rate of remission as defined by complete mucosal healing were observed at the end of treatment. Conclusion These data confirm that alicaforsen enema provides local treatment for a local disease with little meaningful systemic exposure.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Fármacos Gastrointestinais/administração & dosagem , Oligodesoxirribonucleotídeos Antissenso/administração & dosagem , Tionucleotídeos/administração & dosagem , Absorção , Adulto , Área Sob a Curva , Disponibilidade Biológica , Colo/química , Relação Dose-Resposta a Droga , Esquema de Medicação , Enema , Feminino , Fármacos Gastrointestinais/sangue , Fármacos Gastrointestinais/farmacocinética , Humanos , Mucosa Intestinal/química , Masculino , Pessoa de Meia-Idade , Oligodesoxirribonucleotídeos Antissenso/sangue , Oligodesoxirribonucleotídeos Antissenso/farmacocinética , Oligonucleotídeos Fosforotioatos , Tionucleotídeos/sangue , Tionucleotídeos/farmacocinética , Resultado do Tratamento
17.
Leukemia ; 30(2): 274-84, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26376228

RESUMO

Distinct microRNA (miRNA) and mRNA signatures were reported in nucleophosmin (NPM1)-mutated acute myeloid leukemia (AML). However, it remains unknown whether the mutation participates in the dynamic interaction between miRNA and mRNA. In this study, we aimed to investigate the role of NPM1 mutation in modulating miRNA-mRNA regulation (MMR). From the sample-paired miRNA/mRNA microarrays of 181 de novo AML patients, we found that MMR was dynamic and could be affected by NPM1 mutation. By a systematic framework, we identified 493 NPM1 mutation-modulated MMR pairs, where the strength of MMR was significantly attenuated in patients carrying NPM1 mutations, compared to those with wild-type NPM1. These miRNAs/mRNAs were associated with pathways implicated in cancer and known functions of NPM1 mutation. Such modulation of MMR was validated in two independent cohorts as well as in cells with different NPM1 mutant burdens. Furthermore, we showed that the regulatory strength of nine MMR pairs could predict patients' outcomes. Combining these pairs, a scoring system was proposed and shown to predict survival in discovery and validation data sets, independent of other known prognostic factors. Our study provides novel biological insights into the role of NPM1 mutation as a modulator of MMR, based on which a novel prognostic marker is proposed in AML.


Assuntos
Leucemia Mieloide Aguda/genética , MicroRNAs/análise , Mutação , Proteínas Nucleares/genética , RNA Mensageiro/análise , Linhagem Celular Tumoral , Humanos , Leucemia Mieloide Aguda/mortalidade , Nucleofosmina , Prognóstico
18.
Oncogene ; 10(7): 1283-90, 1995 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-7731678

RESUMO

Specific sites of protein-protein interaction were identified in the 51-149 region of c-Raf-1 using contact epitope scanning and site-directed mutagenesis. Nineteen overlapping peptides based upon the primary sequence of the Ras binding domain of c-Raf-1 were tested for the ability to competitively inhibit complex formation between Ras-GTP and the c-Raf-1 N-terminus. A peptide containing c-Raf-1 residues 91-105 as well as five overlapping peptides covering a region extending from residues 118 to 143 interfered with Ras association, defining these sites as potential contact surfaces with Ras. Alanine scanning mutagenesis was used as a second probe for sites of Ras interaction with the c-Raf-1 N-terminus. Raf residues 64-67 and 80-103 were demonstrated as important for association with Ras-GTP with residues 66, 67, 84, 87, 89 and 91 identified as the most critical individual points of contact with the Ras protein. Alanine substitution of residues between 118-143 suggested only one potentially weak site of interaction defined by residues 120-125. The combined results of both peptide and mutagenic analyses suggest that the primary site of c-Raf-1 interaction with Ras maps to Raf residues 80-103, with secondary interactions occurring with residues 66 and 67 and possibly 120-125. Contact epitope scanning of the Ras effector region found maximum inhibition of Ras/Raf association with a peptide corresponding to Ras amino acids 37-51. A model is proposed for the GTP-dependent association of Ras and Raf.


Assuntos
Guanosina Trifosfato/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Mapeamento de Epitopos , Humanos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Peptídeos/química , Peptídeos/metabolismo , Ligação Proteica , Proteínas Proto-Oncogênicas c-raf , Relação Estrutura-Atividade
19.
J Clin Oncol ; 21(9): 1819-24, 2003 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-12721259

RESUMO

PURPOSE: To determine whether biochemical modulation with LV (leucovorin) enhances the efficacy of CAF (cyclophosphamide, doxorubicin, and fluorouracil) against metastatic breast cancer. PATIENTS AND METHODS: Women with histologically confirmed stage IV breast cancer, Cancer and Leukemia Group B (CALGB) performance status 0 to 2, and no prior chemotherapy for metastatic disease were randomly assigned to receive CAF (cyclophosphamide 500 mg/m2 day 1, doxorubicin 40 mg/m2 day 1, and fluorouracil [FU] 200 mg/m2 intravenous bolus days 1 to 5) with or without LV (LV 200 mg/m2 over 30 minutes days 1 to 5 given 1 hour before FU). RESULTS: Two hundred forty-two patients were randomly assigned to treatment; 124 patients had visceral crisis and 40 patients had a CALGB performance status score of 2. The median follow-up was 6 years. The two study arms were similar with regard to serious adverse events; four patients died from treatment-related causes, two patients on each study arm. Predictive variables for time to treatment failure and survival were visceral disease and performance status. The overall response rate was 29% for CAF versus 28% for CAF plus LV. The median time to treatment failure (9 months) and median survival (1.7 years) did not differ by treatment arm. CONCLUSION: Modulation of CAF with LV improved neither response rates nor survival among women with metastatic breast cancer, compared with CAF alone. Multivariate analyses confirmed the prognostic importance of performance status and visceral crisis. However, the overall and complete response rates, response durations, time to treatment failure, and survival were the same in the two treatment arms.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/patologia , Ciclofosfamida/administração & dosagem , Progressão da Doença , Doxorrubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Nível de Saúde , Humanos , Leucovorina/administração & dosagem , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Sobrevida , Resultado do Tratamento , Vísceras/patologia
20.
Leukemia ; 29(5): 1051-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25428263

RESUMO

As a highly heterogeneous disease, acute myeloid leukemia (AML) needs fine risk stratification to get an optimal outcome of patients. MicroRNAs have florid biological functions and have critical roles in the pathogenesis and prognosis in AML. Expression levels of some single microRNAs are influential for prognosis, but a system integrating several together and considering the weight of each should be more powerful. We thus analyzed the clinical, genetic and microRNA profiling data of 138 de novo AML patients of our institute. By multivariate analysis, we identified that high expression of hsa-miR-9-5p and hsa-miR-155-5p were independent poor prognostic factors, whereas that of hsa-miR-203 had a trend to be a favorable factor. We constructed a scoring system from expression of these three microRNAs by considering the weight of each. The scores correlated with distinct clinical and biological features and outperformed single microRNA expression in prognostication. In both ours and another validation cohort, higher scores were associated with shorter overall survival, independent of other well-known prognostic factors. By analyzing the mRNA expression profiles, we sorted out several cancer-related pathways highly correlated with the microRNA prognostic signature. We conclude that this 3-microRNA scoring system is simple and powerful for risk stratification of de novo AML patients.


Assuntos
Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/diagnóstico , MicroRNAs/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aberrações Cromossômicas , Estudos de Coortes , Citogenética , Análise Mutacional de DNA , Feminino , Perfilação da Expressão Gênica , Humanos , Leucemia Mieloide Aguda/metabolismo , Masculino , Análise em Microsséries , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , Reação em Cadeia da Polimerase em Tempo Real , Análise de Regressão , Adulto Jovem
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