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1.
Zhonghua Nei Ke Za Zhi ; 62(4): 374-383, 2023 Apr 01.
Artigo em Chinês | MEDLINE | ID: mdl-37032132

RESUMO

Objectives: To investigated the safety and efficacy of treating patients with acute non-ST-segment elevation myocardial infarction (NSTEMI) and elevated levels of N-terminal pro-hormone B-type natriuretic peptide (NT-proBNP) with levosimendan within 24 hours of first medical contact (FMC). Methods: This multicenter, open-label, block-randomized controlled trial (NCT03189901) investigated the safety and efficacy of levosimendan as an early management strategy of acute heart failure (EMS-AHF) for patients with NSTEMI and high NT-proBNP levels. This study included 255 patients with NSTEMI and elevated NT-proBNP levels, including 142 males and 113 females with a median age of 65 (58-70) years, and were admitted in the emergency or outpatient departments at 14 medical centers in China between October 2017 and October 2021. The patients were randomly divided into a levosimendan group (n=129) and a control group (n=126). The primary outcome measure was NT-proBNP levels on day 3 of treatment and changes in the NT-proBNP levels from baseline on day 5 after randomization. The secondary outcome measures included the proportion of patients with more than 30% reduction in NT-proBNP levels from baseline, major adverse cardiovascular events (MACE) during hospitalization and at 6 months after hospitalization, safety during the treatment, and health economics indices. The measurement data parameters between groups were compared using the t-test or the non-parametric test. The count data parameters were compared between groups using the χ² test. Results: On day 3, the NT-proBNP levels in the levosimendan group were lower than the control group but were statistically insignificant [866 (455, 1 960) vs. 1 118 (459, 2 417) ng/L, Z=-1.25,P=0.21]. However, on day 5, changes in the NT-proBNP levels from baseline in the levosimendan group were significantly higher than the control group [67.6% (33.8%,82.5%)vs.54.8% (7.3%,77.9%), Z=-2.14, P=0.03]. There were no significant differences in the proportion of patients with more than 30% reduction in the NT-proBNP levels on day 5 between the levosimendan and the control groups [77.5% (100/129) vs. 69.0% (87/126), χ²=2.34, P=0.13]. Furthermore, incidences of MACE did not show any significant differences between the two groups during hospitalization [4.7% (6/129) vs. 7.1% (9/126), χ²=0.72, P=0.40] and at 6 months [14.7% (19/129) vs. 12.7% (16/126), χ²=0.22, P=0.64]. Four cardiac deaths were reported in the control group during hospitalization [0 (0/129) vs. 3.2% (4/126), P=0.06]. However, 6-month survival rates were comparable between the two groups (log-rank test, P=0.18). Moreover, adverse events or serious adverse events such as shock, ventricular fibrillation, and ventricular tachycardia were not reported in both the groups during levosimendan treatment (days 0-1). The total cost of hospitalization [34 591.00(15 527.46,59 324.80) vs. 37 144.65(16 066.90,63 919.00)yuan, Z=-0.26, P=0.80] and the total length of hospitalization [9 (8, 12) vs. 10 (7, 13) days, Z=0.72, P=0.72] were lower for patients in the levosimendan group compared to those in the control group, but did not show statistically significant differences. Conclusions: Early administration of levosimendan reduced NT-proBNP levels in NSTEMI patients with elevated NT-proBNP and did not increase the total cost and length of hospitalization, but did not significantly improve MACE during hospitalization or at 6 months.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio sem Supradesnível do Segmento ST , Masculino , Feminino , Humanos , Idoso , Peptídeo Natriurético Encefálico , Simendana/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Fragmentos de Peptídeos , Arritmias Cardíacas , Biomarcadores , Prognóstico
2.
Eur Rev Med Pharmacol Sci ; 22(23): 8406-8414, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30556882

RESUMO

OBJECTIVE: This study aimed to investigate the expressions, clinical significances, roles, and mechanism of action of MRCCAT1 in glioma. PATIENTS AND METHODS: The expression of MRCCAT1 in 103 glioma tissues with different grades and 21 normal brain tissues was measured by qPCR. The prognostic value of MRCCAT1 was investigated by Kaplan-Meier survival analysis. The biological roles of MRCCAT1 on glioma cell proliferation were assessed by Glo cell viability assays and ethynyl deoxyuridine incorporation assays. The roles of MRCCAT1 on glioma cell migration were evaluated by transwell assays. The effects of MRCCAT1 on p38-MAPK signaling were assessed by Western blot. RESULTS: MRCCAT1 is upregulated in glioma tissues and positively associated with glioma grades. Increased expression of MRCCAT1 confers poor prognosis of glioma patients independent of glioma grades. Ectopic expression of MRCCAT1 promotes glioma cell proliferation and migration. Knockdown of MRCCAT1 inhibits glioma cell proliferation and migration. Mechanistically, we found that MRCCAT1 activates p38-MAPK signaling in glioma. CONCLUSIONS: MRCCAT1 is upregulated in glioma. Increased expression of MRCCAT1 predicts poor outcome of glioma patients. MRCCAT1 promotes glioma cell proliferation and migration via activating p38-MAPK signaling. MRCCAT1 may be a potential prognostic biomarker and therapeutic target for glioma.


Assuntos
Neoplasias Encefálicas/genética , Glioma/genética , Oncogenes , RNA Longo não Codificante/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Glioma/metabolismo , Glioma/mortalidade , Glioma/patologia , Humanos , Prognóstico , RNA Longo não Codificante/metabolismo , Transdução de Sinais , Regulação para Cima , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
3.
Br J Anaesth ; 121(2): 350-357, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30032873

RESUMO

BACKGROUND: A biomarker test based on a combination of urine tissue inhibitor of metalloproteinases 2 (TIMP-2) and insulin-like growth factor binding protein 7 (IGFBP7) has been used as a potential biomarker of acute kidney injury (AKI). This meta-analysis aimed to evaluate the predictive value of this biomarker for cardiac surgery-associated acute kidney injury (CSA-AKI). METHODS: We searched MEDLINE, PubMed, Cochrane, and EMBASE for studies. We evaluated the methodological quality of each included study using the Quality Assessment of Diagnostic Accuracy Studies 2 criteria. Meta-DiSc and STATA were used for statistical analyses. RESULTS: A total of 10 studies (747 patients) were included in this meta-analysis. Pooled sensitivity and specificity with corresponding 95% confidence intervals (CI) were 0.77 (95% CI: 0.70-0.83, I2=40.7%) and 0.76 (95% CI: 0.72-0.79, I2=69.1%), respectively. Pooled positive likelihood ratio (LR), negative LR, and diagnostic odds ratio were 3.26 (95% CI: 2.51-4.23, I2=50.7%), 0.32 (95% CI: 0.24-0.41, I2=6.7%), and 10.08 (95% CI: 6.85-14.84, I2=6.7%), respectively. The area under the curve estimated by summary receiver operating characteristics was 0.83 [standard error (SE) 0.023] with a Q* value of 0.759 (se 0.021). There was no heterogeneity amongst the 10 studies from both threshold and non-threshold effects. Subgroup analysis showed that the diagnostic value was related to the severity of AKI and time measurement. CONCLUSIONS: Urinary [TIMP-2]·[IGFBP7] is an effective predictive test for cardiac surgery associated acute kidney injury with good diagnostic accuracy within 24 h. Studies examining use of biomarker-guided care bundles are indicated.


Assuntos
Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Biomarcadores/análise , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Pontos de Checagem do Ciclo Celular/fisiologia , Complicações Pós-Operatórias/diagnóstico , Humanos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/análise , Valor Preditivo dos Testes , Inibidor Tecidual de Metaloproteinase-2/análise
4.
5.
Prostate Cancer Prostatic Dis ; 20(1): 48-54, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27595916

RESUMO

BACKGROUND: Epidemiologic and laboratory evidence supports a role for cholesterol in prostate cancer (PC). Dietary saturated fat content impacts serum cholesterol levels. However, epidemiologic associations between saturated fat and PC aggressiveness are inconsistent. We hypothesized that high saturated fat intake would be associated with increased PC aggressiveness, and that statin use would modify this association. METHODS: Of 1854 PC cases in the North Carolina-Louisiana PC Project, 321 (17%) were classified as high aggressive (Gleason sum ⩾8, PSA>20 ng ml-1, or Gleason sum ⩾7 and clinical stage T3-4) or low/intermediate aggressive (all other cases). Using low/intermediate aggressive cases as the referent group, we examined the association between tertiles of total fat-adjusted saturated fat intake and high aggressive PC using logistic regression, overall and stratified by race and statin use. We examined total fat-adjusted polyunsaturated and monounsaturated fatty acids (PUFA and MUFA, respectively), trans fat and cholesterol intake in secondary analysis. RESULTS: High total fat-adjusted saturated fat intake was associated with an elevated odds ratio (OR) for aggressive PC (ORT3vsT1 1.51; 95% CI 1.10-2.06; P-trend=0.009), with an attenuated association in statin users (ORT3vsT1 1.16; 95% CI 0.67-2.01; P-trend=0.661) compared with non-users (ORT3vsT1 1.71; 95% CI 1.16-2.51; P-trend=0.053). High total fat-adjusted cholesterol intake was associated with aggressive PC in European Americans (ORT3vsT1 1.62; 95% CI 1.02-2.58; P-trend=0.056), but not African Americans (ORT3vsT1 0.92; 95% CI 0.60-1.42; P-trend=0.750). High total fat-adjusted PUFA was inversely associated with PC aggressiveness (ORT3vsT1 0.75; 95% CI 0.55-1.03), although this was not significant. No associations were found between total fat-adjusted MUFA or trans fat and PC aggressiveness. CONCLUSIONS: High total fat-adjusted saturated fat intake was associated with increased PC aggressiveness, with a suggestion of a stronger effect in men not using statins. The association between total fat-adjusted cholesterol intake and PC aggressiveness was most pronounced in European Americans.


Assuntos
Gorduras na Dieta , Ácidos Graxos , Comportamento Alimentar , Neoplasias da Próstata/etiologia , Neoplasias da Próstata/patologia , Adulto , Idoso , Biomarcadores Tumorais , Gorduras na Dieta/efeitos adversos , Progressão da Doença , Ácidos Graxos/efeitos adversos , Humanos , Louisiana/epidemiologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , North Carolina/epidemiologia , Razão de Chances , Vigilância da População , Neoplasias da Próstata/epidemiologia , Fatores Socioeconômicos
6.
Genet Mol Res ; 14(4): 13954-67, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26535711

RESUMO

Tsaitermes ampliceps (lower termites) and Mironasutitermes shangchengensis (higher termites) are highly eusocial insects that thrive on recalcitrant lignocellulosic diets through nutritional symbioses with gut dwelling prokaryotes and eukaryotes. We used denaturing gradient gel electrophoresis and a 16S rRNA clone library to investigate i) how microbial communities adapt to lignocellulosic diets with different cellulose and lignin content, ii) the differences in the dominant gut microbial communities of the 2 types of termites. The results indicated that gut microbiota composition in T. ampliceps was profoundly affected by 2-week diet shifts. Comparison of these changes indicated that Bacteroidetes and Spirochaetes act in cellulose degradation, while Firmicutes were responsible for lignin degradation. Additionally, Proteobacteria consistently participated in energy production and balanced the gut environment. Bacteroidetes may function without hindgut protozoans in higher termites. The diversity of enteric microorganisms in M. shangchengensis was higher than that in T. ampliceps, possibly because of the more complicated survival mechanisms of higher termites.


Assuntos
Ração Animal , Microbioma Gastrointestinal , Isópteros/microbiologia , Lignina , Animais , Biodiversidade , Análise por Conglomerados , Metagenoma , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
7.
Genet Mol Res ; 13(3): 7926-36, 2014 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-25299108

RESUMO

Locusts are able to digest the cellulose of Gramineae plants, resulting in their being considered as major crop pests. To illustrate the mechanism involved in cellulose digestion, the cellulolytic activity and zymography in the gut contents of 16 locust species were determined using carboxymethyl cellulose (CMC) as substrate. The diversity of gut symbiotic bacteria was studied using denaturing gradient gel electrophoresis (DGGE). The results showed that high CMC activity was present in Acrididae gut fluid (mean 356.4 U/g proteins). Of the 5 locust species, Oxya chinensis had the highest diversity of intestinal symbiotic bacteria, characterized by the DGGE profile containing more than 20 bands of 16S rRNA. Klebsiella pneumoniae, in the gut of Locusta migratoria manilensis, was identified as the most abundant symbiotic bacterium by DNA sequencing, with a relative abundance of 19.74%. In comparison, Methylobacterium sp was the most dominant species in the Atractomorpha sinensis gut, with a relative abundance of 29.04%. The results indicated that the cellulolytic enzymes and gut microbial communities probably reflected their phylogenetic relationship with different locust species and associated feeding strategies.


Assuntos
Bactérias/metabolismo , Celulose/metabolismo , Sistema Digestório/microbiologia , Gafanhotos/microbiologia , Simbiose , Animais , Bactérias/genética , Sequência de Bases , Primers do DNA , Hidrólise , Eletroforese em Gel de Poliacrilamida Nativa , RNA Ribossômico 16S/genética
8.
J Biomed Nanotechnol ; 10(7): 1267-76, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24804547

RESUMO

Nanomaterial-directed, photothermal ablation is a practical future approach for the treatment of early-stage bladder cancer. Using a new PEGylation technique with bi-functional nitrophenyl carbonate PEG (bi-NPC-PEG) that promotes uniform suspension of the nanomaterial in solution, we have shown that gold nanorods conjugated to an anti-EGFR antibody (nano-alphaEGFR) bind effectively to EGFR-expressing bladder cancer cells. The subsequent application of infrared light, specifically tuned to the plasmon resonance of the nanorods used in this work, allows for the specific heating of nano-alphaEGFR to the point of localized cellular death. Such an approach, administering nano-alphaEGFR intravesically via a urinary catheter and infrared light via a modified cystoscope, represents a novel, future clinical application of this technology, which avoids the problem of systemic exposure and clearance of nanoparticles from body.


Assuntos
Técnicas de Ablação , Ouro/uso terapêutico , Hipertermia Induzida , Nanotubos/química , Neoplasias da Bexiga Urinária/terapia , Morte Celular , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Humanos , Microscopia de Fluorescência , Nanoconjugados/ultraestrutura , Nanotubos/ultraestrutura , Polietilenoglicóis/química , Espectrofotometria Atômica
9.
Genet Mol Res ; 12(3): 2432-41, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23315870

RESUMO

Efficient and low-cost cellulolytic enzymes are urgently needed to degrade recalcitrant plant biomass during the industrial production of lignocellulosic biofuels. Here, the cellulolytic activities in the gut fluids of 54 insect species that belong to 7 different taxonomic orders were determined using 2 different substrates, carboxymethyl cellulose (CMC) (approximating endo-ß-1,4-glucanase) and filter paper (FP) (total cellulolytic activities). The use of CMC as the substrate in the zymogram analysis resulted in the detection of distinct cellulolytic protein bands. The cellulolytic activities in the digestive system of all the collected samples were detected using cellulolytic activity analysis. The highest CMC gut fluid activities were found in Coleoptera and Orthoptera, while FP analysis indicated that higher gut fluid activities were found in several species of Coleoptera and Lepidoptera. In most cases, gut fluid activities were higher with CMC than with FP substrate, except for individual Lepidoptera species. Our data indicate that the origin of cellulolytic enzymes probably reflects the phylogenetic relationship and feeding strategies of different insects.


Assuntos
Carboximetilcelulose Sódica/química , Besouros/enzimologia , Trato Gastrointestinal/enzimologia , Lepidópteros/enzimologia , Animais , Besouros/anatomia & histologia , Hidrólise , Lepidópteros/anatomia & histologia
10.
J Int Med Res ; 38(4): 1343-53, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20926007

RESUMO

In some cancer cell lines, the gene encoding activin A (inhibin ßA [INHBA]) is over-expressed and enhances cancer proliferation. Protein levels of activin A and follistatin were assessed in glioblastoma and normal brain tissues in this study, and the effect of activin A and follistatin treatment on the proliferation of U87 human glioblastoma cells in vitro was also studied. High levels of activin A were observed in glioblastomas compared with normal brain tissue. In contrast, follistatin levels were similar between the two tissues. [(3)H]Thymidine assay showed that activin A (3 - 30 ng/ml) produced a dose-dependent increase in DNA synthesis of U87 cells compared with controls. Flow cytometric analyses showed that activin A increased the proliferative index of U87 cells compared with controls. Activin A also induced up-regulation of p-SMAD2/3 in a dose-dependent manner. Treatment of U87 cells with follistatin blocked these activin A-induced effects. The disequilibrium between activin A and follistatin may play a role in the development of glioblastoma.


Assuntos
Ativinas/metabolismo , Folistatina/metabolismo , Glioblastoma/metabolismo , Ativinas/genética , Adulto , Idoso , Bioensaio , Western Blotting , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA de Neoplasias/biossíntese , Feminino , Citometria de Fluxo , Folistatina/genética , Folistatina/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Smad/metabolismo , Timidina/metabolismo , Trítio/metabolismo
11.
J Neurosci Res ; 74(2): 248-54, 2003 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-14515354

RESUMO

Gas7, a growth arrest-specific gene originally isolated from serum-starved mouse fibroblast cells, is expressed in vivo predominantly in the brain and is required for neurite formation in cultured mouse cerebellar neurons (Ju et al. [1998] Proc. Natl. Acad. Sci. USA 95: 11423-11428). Here we report that Gas7 plays a key role in the morphological differentiation of PC12 preneuronal rat pheochromocytoma cells (PC12 cells). We found that overexpression of murine Gas7 in PC12 cells leads to an expanded cell morphology and promotes spike-like cell processes that resemble the early stages of neurite formation. These processes undergo elongation upon addition of nerve growth factor (NGF). We also found that the addition of NGF induces the production of endogenous rat-Gas7 (rGas7), which is transiently elevated prior to the appearance of NGF-promoted neurite outgrowths. Furthermore, inhibition of endogenous rGas7 production by antisense nucleotides complimentary to the translation initiation region of a rGas7 cDNA (AJ131902) reduces the NGF-promoted neurite outgrowths. Our results demonstrate that Gas7 by itself influences early cell morphological development and likely functions as an early-stage intermediary in NGF-induced neuronal differentiation of PC12 culture cells.


Assuntos
Diferenciação Celular/fisiologia , Sistema Nervoso Central/embriologia , Fator de Crescimento Neural/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neuritos/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Tamanho Celular/fisiologia , Sistema Nervoso Central/citologia , Sistema Nervoso Central/metabolismo , Dados de Sequência Molecular , Fator de Crescimento Neural/farmacologia , Proteínas do Tecido Nervoso/agonistas , Proteínas do Tecido Nervoso/antagonistas & inibidores , Neuritos/efeitos dos fármacos , Neuritos/ultraestrutura , Oligonucleotídeos Antissenso/farmacologia , Células PC12 , Ratos
12.
Am Surg ; 67(11): 1068-71, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11730223

RESUMO

Tumor growth and the development of metastases require an angiogenic response. Angiogenic vessels uniquely express somatostatin subtype 2 (sst 2) receptors that can transport somatostatin or its analogs into the cell. We hypothesized that radiolabeled somatostatin analogs could inhibit the angiogenic response by selectively destroying proliferating endothelial cells. We evaluated the antiangiogenic effects of 111In-pentetreotide, an sst 2-preferring somatostatin analog in a human vessel model. Disks of human placental vein were embedded in fibrin gels in culture and observed for angiogenic sprouting for 14 days. Vein disks were treated with 111In-pentetreotide (1.5, 15, and 150 microCi/mL) on the day of implantation. Control groups included disks treated with nutrient medium alone, with 111In-chloride, and with unlabeled pentetreotide. The percentage of wells that initiated an angiogenic response and the overall length and density of neovessel sprouts were assessed on Day 14. 111In-pentetreotide treatment did not completely block initiation of the angiogenic response but significantly decreased the growth of neovessels after initiation. Both the receptor-specific Auger electron-induced and nonspecific gamma radiation-mediated effects contributed to the angiotoxicity.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Endotélio Vascular/citologia , Radioisótopos de Índio/farmacologia , Neovascularização Patológica/prevenção & controle , Somatostatina/farmacologia , Células Cultivadas , Humanos , Radioisótopos de Índio/administração & dosagem , Radioisótopos de Índio/uso terapêutico , Somatostatina/administração & dosagem , Somatostatina/análogos & derivados , Somatostatina/uso terapêutico
13.
J Dermatol Sci ; 27(2): 82-7, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11532371

RESUMO

The human homolog of KET, p63, bears strong homology to the tumor suppressor p53 and plays an essential role in epithelial development. CUSP, the most abundant cutaneous product of p63, has been identified as an autoantigen in chronic ulcerative stomatitis (CUS). The original report of KET expression at least partially contradicts p63 expression subsequently reported by many different groups. We have examined p63 expression by Northern analysis of RNA from multiple human tissues and by indirect immunofluorescence of rat tissue with CUS patient sera. Northern analysis reveals p63 RNA in skin, thymus, placenta, skeletal muscle, kidney, and lung, with non-transactivating p63 RNA in skin, thymus, and placenta. Reverse transcriptase polymerase chain reaction (rtPCR) assays show abundant non-transactivating p63 RNA, and little to no transactivating p63 RNA, in human basal cell carcinoma as well as in normal skin adjacent to the tumors. p63 RNA expression was not detected in brain, heart, colon, spleen, liver, or small intestine. Immunofluorescence reveals p63 expression in skin, oral epithelium, tongue, kidney, and trachea, but not in liver, large intestine, testis, skeletal muscle, or heart. Focal p63 expression within tissues, the complex array of isoforms encoded by the gene, and the specificity of the probes and antibodies utilized, may all contribute to contradictory accounts of CUSP/p63 expression.


Assuntos
Genes Supressores de Tumor , Gengivite Ulcerativa Necrosante/genética , Proteínas de Membrana , Fosfoproteínas/genética , Transativadores/genética , Transcrição Gênica , Proteína Supressora de Tumor p53 , Animais , Proteínas de Ligação a DNA , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Variação Genética , Humanos , Rim/metabolismo , Masculino , Mucosa Bucal/metabolismo , Especificidade de Órgãos , Fosfoproteínas/análise , RNA Mensageiro/genética , Ratos , Pele/metabolismo , Língua/metabolismo , Traqueia/metabolismo , Transativadores/análise , Fatores de Transcrição , Proteínas Supressoras de Tumor
14.
EMBO J ; 20(8): 2051-61, 2001 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-11296237

RESUMO

Group II introns are well recognized for their remarkable catalytic capabilities, but little is known about their three-dimensional structures. In order to obtain a global view of an active enzyme, hydroxyl radical cleavage was used to define the solvent accessibility along the backbone of a ribozyme derived from group II intron ai5gamma. These studies show that a highly homogeneous ribozyme population folds into a catalytically compact structure with an extensively internalized catalytic core. In parallel, a model of the intron core was built based on known tertiary contacts. Although constructed independently of the footprinting data, the model implicates the same elements for involvement in the catalytic core of the intron.


Assuntos
Íntrons , RNA Catalítico/química , Sequência de Bases , Domínio Catalítico , Radical Hidroxila , Modelos Moleculares , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Solventes
15.
J Mol Biol ; 306(4): 655-68, 2001 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-11243778

RESUMO

The mechanism by which group II introns cleave the correct phosphodiester linkage was investigated by studying the reaction of mutant substrates with a ribozyme derived from intron ai5gamma. While fidelity was found to be quite high in most cases, a single mutation on the substrate (+1C) resulted in a dramatic loss of fidelity. When this mutation was combined with a second mutation that induces a bulge in the exon binding site 1/intron binding site 1 (EBS1/IBS1) duplex, the base-pairing register of the EBS1/IBS1 duplex was shifted and the cleavage site moved to a downstream position on the substrate. Conversely, when mismatches were incorporated at the EBS1/IBS1 terminus, the duplex was effectively truncated and cleavage occurred at an upstream site. Taken together, these data demonstrate that the cleavage site of a group II intron ribozyme can be tuned at will by manipulating the thermodynamic stability and structure of the EBS1/IBS1 pairing. The results are consistent with a model in which the cleavage site is not designated through recognition of specific nucleotides (such as the 5'-terminal residue of EBS1). Instead, the ribozyme detects a structure at the junction between single and double-stranded residues on the bound substrate. This finding explains the puzzling lack of phylogenetic conservation in ribozyme and substrate sequences near group II intron target sites.


Assuntos
Íntrons/genética , Precursores de RNA/metabolismo , RNA Catalítico/genética , RNA Catalítico/metabolismo , Pareamento Incorreto de Bases , Pareamento de Bases , Sequência de Bases , Sítios de Ligação , Cátions Bivalentes/metabolismo , Éxons/genética , Cinética , Modelos Genéticos , Mutação/genética , Precursores de RNA/química , Precursores de RNA/genética , RNA Catalítico/classificação , Endonucleases Específicas para DNA e RNA de Cadeia Simples/metabolismo , Especificidade por Substrato , Termodinâmica
16.
Ann Epidemiol ; 11(1): 65-72, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11164122

RESUMO

PURPOSE: This manuscript utilized the NHANES I Epidemiologic Follow-up Study (NHEFS), a national probability sample of the U.S. non-institutionalized population, to examine whether the intake of folate at baseline is associated with colon cancer risk. METHODS: The NHEFS consists of 14,407 subjects with 20 years of follow-up. Sociodemographic status, dietary information, family history of colon cancer, alcohol and aspirin use, smoking status, and body mass index (BMI) are included in the Cox proportional hazard model to examine confounding effects. RESULTS: After adjusting for confounders, a marginally significant association was observed between folate intake and reduced colon cancer risk. Gender and alcohol consumption appears to have an interactive effect with this association. The stratified results suggest that dietary folate is significantly inversely associated with colon cancer in men (relative risk (RR) = 0.40, 95% confidence interval (CI) = 0.18, 0.88) who consumed more than 249 microg/day of folate and that there is a significant dose-response relationship (p = 0.03). The association did not reach statistical significance in women. Using a composite dietary profile, we found that there is a significantly increased risk for men who consumed low-folate, low-methionine, and high alcohol diets when compared to male non-drinkers who consumed high-folate and high methionine diets (RR = 2.67, 95% CI = 1.16, 6.16). CONCLUSIONS: This study found significant association between folate intake and reduced colon cancer risk among men and non-drinkers, but not women or drinkers. The study supports a synergistic interaction between intakes of folate, methionine and alcohol and colon cancer risk.


Assuntos
Neoplasias do Colo/epidemiologia , Ácido Fólico/administração & dosagem , Estado Nutricional , Adulto , Idoso , Consumo de Bebidas Alcoólicas , Dieta , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Metionina/administração & dosagem , Pessoa de Meia-Idade , Fatores de Risco , Fumar , Estados Unidos/epidemiologia
17.
J Invest Dermatol ; 113(2): 146-51, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10469295

RESUMO

A unique clinical syndrome has been described in which patients have chronic oral ulceration and autoantibodies to nuclei of stratified squamous epithelium. We have characterized the autoantibodies from patients sera and found that the major autoantigen is a 70 kDa epithelial nuclear protein. Sequencing of the cDNA for this protein, chronic ulcerative stomatitis protein, revealed it to be homologous to the p53 tumor suppressor and to the p73 putative tumor suppressor, and to be a splicing variant of the KET gene. The p53-like genes, p73 and the several KET splicing variants, are recently described genes of uncertain biologic and pathologic significance. This study provides the first clear association of a p53-like protein with a disease process.


Assuntos
Autoantígenos/sangue , Gengivite Ulcerativa Necrosante/sangue , Gengivite Ulcerativa Necrosante/imunologia , Autoantígenos/genética , Sequência de Bases , Sítios de Ligação de Anticorpos , Núcleo Celular/química , Imunofluorescência , Genes p53 , Humanos , Queratinócitos/imunologia , Queratinócitos/ultraestrutura , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos
18.
Am J Obstet Gynecol ; 177(3): 579-85, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9322627

RESUMO

OBJECTIVE: Our goal was to determine whether toxicity of the diphtheria toxin A-chain gene regulated by the human chorionic gonadotropin promoter can be directed to malignant ovarian cell lines. STUDY DESIGN: Plasmids containing diphtheria toxin A-chain gene linked to the regulatory elements of the metalloergothioneine and human chorionic gonadotropin promoters were transfected into the cell lines. Expression of diphtheria toxin A-chain gene was determined by the inhibition of a cotransfected luciferase reporter gene. RESULTS: Cytotoxicity of the diphtheria toxin A-chain gene is shown in a dose-responsive manner. Transfection of a plasmid expressing the diphtheria toxin A-chain gene controlled by a constitutive promoter readily inhibits protein synthesis. Specific inhibition of luciferase protein synthesis occurs in ovarian cancer cells transfected with the diphtheria toxin A-chain gene under the control of the human chorionic gonadotropin promoters when compared with normal ovarian epithelial cells or fibroblasts. CONCLUSIONS: These data demonstrate the preferential expression of the diphtheria toxin A-chain gene, regulated by the human chorionic gonadotropin promoter, to ovarian cancer cell lines. This provides an avenue for targeting such cells for suicide, toxin, or cytokine genes.


Assuntos
Carcinoma/patologia , Gonadotropina Coriônica/genética , Toxina Diftérica/genética , Neoplasias Ovarianas/patologia , Regiões Promotoras Genéticas/fisiologia , Carcinoma/química , Carcinoma/metabolismo , Gonadotropina Coriônica/análise , Gonadotropina Coriônica/fisiologia , Gonadotropina Coriônica Humana Subunidade beta/análise , Gonadotropina Coriônica Humana Subunidade beta/metabolismo , Toxina Diftérica/fisiologia , Toxina Diftérica/toxicidade , Relação Dose-Resposta a Droga , Células Epiteliais/citologia , Epitélio/química , Epitélio/metabolismo , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Luciferases/análise , Luciferases/genética , Neoplasias Ovarianas/química , Neoplasias Ovarianas/metabolismo , Ovário/química , Ovário/citologia , Ovário/metabolismo , Fragmentos de Peptídeos/análise , Fragmentos de Peptídeos/metabolismo , Plasmídeos , Regiões Promotoras Genéticas/genética , Transfecção , Células Tumorais Cultivadas
19.
J Adolesc Health ; 20(6): 426-33, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9178079

RESUMO

PURPOSE: The purpose of this study was to explore whether adolescents of substance-abusing and depressed parents were more likely to have poor dietary behaviors than those in the health comparison families. METHODS: The sample consisted of 841 adolescents in families of substance-abusing parents, depressed parents, and parents without a diagnosable psychiatric disorder. All adolescents were given a food frequency questionnaire. RESULTS: Adolescents whose parents had substance abuse disorder had lower intakes of fruits and higher intakes of high fat foods, and also ate more frequently at fast-food restaurants and purchased more snacks. Adolescents whose parents were depressed had lower intakes of all food groups. Mother's mental health status impacted more on adolescents' dietary behaviors than did the father's mental health status. CONCLUSION: This research suggests that at-risk behaviors among youth of psychiatrically impaired parents may extend to food behaviors.


Assuntos
Filho de Pais com Deficiência/psicologia , Transtorno Depressivo/psicologia , Comportamento Alimentar/psicologia , Transtornos Relacionados ao Uso de Substâncias/psicologia , Adolescente , Adulto , Chicago/epidemiologia , Criança , Estudos de Coortes , Transtorno Depressivo/epidemiologia , Transtorno Depressivo/genética , Relações Pai-Filho , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Relações Mãe-Filho , Inquéritos Nutricionais , Estudos Prospectivos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/genética
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