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1.
Eur Rev Med Pharmacol Sci ; 26(4): 1114-1124, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35253166

RESUMEN

OBJECTIVE: To evaluate the efficacy and safety of HSK3486 for the induction and maintenance of general anesthesia in elective surgical patients, but excluding emergency, cardiothoracic, cerebral and endoscopic sinus cases. PATIENTS AND METHODS: A total of 40 eligible patients were randomly assigned to HSK3486 (n = 30) or propofol (n = 10) dosage groups in a ratio of 3:1. Drugs were administered as a bolus injection of 0.4 mg/kg (HSK3486) or 2.0 mg/kg (propofol) for induction, followed by maintenance infusion with the same anesthetic. An additional 6 non-randomized patients received propofol (2.0 mg/kg) for induction and were given HSK3486 for maintenance. RESULTS: The primary efficacy endpoint - the success rate of anesthesia maintenance - was 100% in the 3 arms. The secondary efficacy endpoints included times from discontinuation of HSK3486 or propofol maintenance to full alertness, respiratory recovery, extubation and reaching the goal of the Aldrete score. Also, the proportion of patients who constantly maintained BIS40-60 or those with a period of BIS40-60 during maintenance anesthesia showed no significant difference in the HSK3486 and propofol groups (all p > 0.05). Patients who received HSK3486 exhibited a higher satisfaction score from anesthesiologists during the induction period (p = 0.024). The occurrence and types of treatment-emergent adverse events were similar among the 3 arms, both with a severity of grade 1 or 2. Drug-related hypotension occurred in 14 (46.7%) and 7 (70.0%) patients treated with HSK3486 and propofol, respectively. CONCLUSIONS: HSK3486 exhibited good efficacy for the induction and maintenance of general anesthesia and was well tolerated by patients who underwent elective surgery.


Asunto(s)
Hipotensión , Propofol , Anestesia General/efectos adversos , Anestésicos Intravenosos/efectos adversos , Procedimientos Quirúrgicos Electivos , Humanos , Hipotensión/inducido químicamente , Propofol/efectos adversos
2.
Oncogene ; 35(30): 3897-908, 2016 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-26616862

RESUMEN

Integrin-linked kinase (ILK) is a mediator of aggressive phenotype in pancreatic cancer. On the basis of our finding that knockdown of either KRAS or ILK has a reciprocal effect on the other's expression, we hypothesized the presence of an ILK-KRAS regulatory loop that enables pancreatic cancer cells to regulate KRAS expression. This study aimed to elucidate the mechanism by which this regulatory circuitry is regulated and to investigate the translational potential of targeting ILK to suppress oncogenic KRAS signaling in pancreatic cancer. Interplay between KRAS and ILK and the roles of E2F1, c-Myc and heterogeneous nuclear ribonucleoprotein as intermediary effectors in this feedback loop was interrogated by genetic manipulations through small interfering RNA/short hairpin RNA knockdown and ectopic expression, western blotting, PCR, promoter-luciferase reporter assays, chromatin immunoprecipitation and pull-down analyses. In vivo efficacy of ILK inhibition was evaluated in two murine xenograft models. Our data show that KRAS regulated the expression of ILK through E2F1-mediated transcriptional activation, which, in turn, controlled KRAS gene expression via hnRNPA1-mediated destabilization of the G-quadruplex on the KRAS promoter. Moreover, ILK inhibition blocked KRAS-driven epithelial-mesenchymal transition and growth factor-stimulated KRAS expression. The knockdown or pharmacological inhibition of ILK suppressed pancreatic tumor growth, in part, by suppressing KRAS signaling. These studies suggest that this KRAS-E2F1-ILK-hnRNPA1 regulatory loop enables pancreatic cancer cells to promote oncogenic KRAS signaling and to interact with the tumor microenvironment to promote aggressive phenotypes. This regulatory loop provides a mechanistic rationale for targeting ILK to suppress oncogenic KRAS signaling, which might foster new therapeutic strategies for pancreatic cancer.


Asunto(s)
Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/fisiología , Neoplasias Pancreáticas/patología , Proteínas Serina-Treonina Quinasas/fisiología , Proteínas Proto-Oncogénicas p21(ras)/fisiología , Transducción de Señal/fisiología , Animales , Línea Celular Tumoral , Factor de Transcripción E2F1/fisiología , Transición Epitelial-Mesenquimal , Ribonucleoproteína Nuclear Heterogénea A1 , Humanos , Ratones , Proteínas Proto-Oncogénicas c-myc/fisiología , Proteínas Proto-Oncogénicas p21(ras)/genética , Activación Transcripcional
4.
Eur Rev Med Pharmacol Sci ; 17(3): 410-9, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23426547

RESUMEN

BACKGROUND: In the last few years there have been changed in the pattern of consumption of antihypertensive drugs in other countries. Factors causing this variability include differences in the effectiveness of detection, guidelines for the management of hypertension, and differences in national health insurance systems among countries. AIM: The aim of this study was to reveal patterns in the use of antihypertensive drugs in Taiwan over a six year period (2001 to 2006) and compare these results with data from other countries. MATERIALS AND METHODS: This study performed descriptive analysis of data from the National Health Insurance Research Database (NHIRD) of Taiwan, and compared these findings with similar findings from around the world. Quantities were standardized using the defined daily dose (DDD) per 1000 inhabitants per day (DID) in accordance with WHO anatomical therapeutic classification and DDD measurement methodology. RESULTS: The total number of DDDs prescribed in Taiwan increased from 0.66 billion in 2001 to 1.08 billion in 2006, representing 80.6 and 129.2 DID in 2001 and 2006, respectively. This indicates a significant increase in the prescription of antihypertensive drugs in Taiwan over this period. The average annual increase ranged from 10.7% for calcium channel blockers (CCBs) to 22.1% for angiotensin II receptor blockers (ARBs). All of these patterns were statistically significant (p < 0.05). The rapid increase in the use of ARBs resulted in its surpassing ACEIs with the second highest DID (21.9) in 2006. Though the proportional use of CCBs and ARBs has increased significantly, the use of thiazide diuretics remains low. CONCLUSIONS: The consumption of antihypertension drugs in Taiwan increased during the period studied and the highest average annual increases were for ARBs and CCBs. Overall consumption of antihypertension drugs also increased in other countries, but differences in the relative increase for each class of drug suggest that further study may be required to clarify the origins and causes.


Asunto(s)
Antagonistas de Receptores de Angiotensina/uso terapéutico , Antihipertensivos/uso terapéutico , Bloqueadores de los Canales de Calcio/uso terapéutico , Hipertensión/tratamiento farmacológico , Antagonistas de Receptores de Angiotensina/administración & dosificación , Antihipertensivos/administración & dosificación , Bloqueadores de los Canales de Calcio/administración & dosificación , Bases de Datos Factuales , Humanos , Programas Nacionales de Salud , Guías de Práctica Clínica como Asunto , Inhibidores de los Simportadores del Cloruro de Sodio/administración & dosificación , Inhibidores de los Simportadores del Cloruro de Sodio/uso terapéutico , Taiwán
5.
Transplant Proc ; 43(7): 2714-7, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21911151

RESUMEN

PURPOSE: To investigate the effect of an early postoperative outpatient cardiac rehabilitation program to health-related quality of life among heart transplantation recipients (HTR) and patients with coronary artery bypass graft (CABG) surgery. METHODS: The study included 45 clinically stable HTR (age: 47 ± 14 years; 36 men, 9 women) and 34 patients with CABG (age: 57.2 ± 12.5 years; 27 men, 7 women). HTR started rehabilitation 70 ± 33 days after transplantation; patients with CABG started training 36 ± 18 days after surgery. Patients participated in a 12-week supervised exercise training program three times per week. Each training session comprised 10 minutes of warm-up, 25 to 30 minutes of cycling or treadmill walking, and 10 minutes of cooldown. The exercise intensity was set at 50% to 80% of peak oxygen uptake (V̇O(2peak)) according to the patient's condition. The health-related quality of life of subjects was evaluated by the Medical Outcomes Trust 36-item health survey (SF-36) at baseline and upon the completion of rehabilitation. RESULTS: At baseline, the HTR group showed lower V̇O(2peak) than the CABG group, but the health-related quality of life was similar between the two groups. After training, both groups exhibited an increase of 3.6 mL·kg(-1)·min(-1) in V̇O(2peak) and improvement of physical component in health-related quality of life. The HTR group showed a significant increase of SF-36 scores in physical functioning (59.7 ± 18.9 to 77.0 ± 14.0), physical role (21.1 ± 34.1 to 38.3 ± 37.9), bodily pain (57.4 ± 24.3 to 73.6 ± 21.5), social functioning (63.6 ± 23.4 to 72.8 ± 22.1), emotional role (59.2 ± 43.7 to 76.3 ± 37.4), and mental health (67.1 ± 17.9 to 73.4 ± 14.6). The CABG group only exhibited increased scores in physical functioning (60.0 ± 22.9 to 73.4 ± 18.0), physical role (19.1 ± 24.9 to 27.9 ± 38.3), bodily pain (57.1 ± 20.0 to 70.3 ± 16.1), and social functioning (54.0 ± 21.3 to 69.9 ± 21.1). CONCLUSIONS: Early postoperative cardiac rehabilitation significantly improved physical capacity and quality of life among heart transplant recipients and patients with CABG. Additionally, HTR showed greater improvement in health-related quality of life than patients with CABG regardless of lower physical capacity.


Asunto(s)
Puente de Arteria Coronaria , Cardiopatías/rehabilitación , Trasplante de Corazón , Calidad de Vida , Adulto , Prueba de Esfuerzo , Femenino , Cardiopatías/fisiopatología , Humanos , Masculino , Persona de Mediana Edad
6.
Tob Control ; 14 Suppl 1: i62-70, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15923452

RESUMEN

OBJECTIVE: To estimate the smoking attributable medical expenditures and productivity loss of people aged 35 and over in Taiwan in 2001 from a societal viewpoint. METHODS: A prevalence based approach was used to estimate smoking attributable costs. Epidemiological parameters were obtained from two follow up studies and government statistics. Data on medical care utilisation and expenditure were extracted from the National Health Insurance claim data. RESULTS: Total smoking attributable medical expenditures (SAEs) amounted to USD 397.6 million, which accounted for 6.8% of the total medical expenditures for people aged 35 and over. Mean annual medical expenditures per smoker was USD 70 more than that of each non-smoker. Smoking attributable years of potential life lost (YPLL) totalled to 217,761 years for males and 15,462 years for females, and the corresponding productivity loss was USD 1371 million for males and USD 18.7 million for females. CONCLUSION: Medical expenditures attributable to smoking accounted for 6.8% of the total medical expenditure of people aged 35 and over for the year 2001 in Taiwan. Corresponding YPLL and productivity loss also demand that actions be taken to fight cigarette smoking.


Asunto(s)
Costos de la Atención en Salud/estadística & datos numéricos , Fumar/economía , Adulto , Distribución por Edad , Anciano , Atención Ambulatoria/economía , Causas de Muerte , Femenino , Hospitalización/economía , Humanos , Esperanza de Vida , Masculino , Persona de Mediana Edad , Neoplasias/mortalidad , Prevalencia , Factores de Riesgo , Distribución por Sexo , Fumar/efectos adversos , Fumar/epidemiología , Taiwán/epidemiología
7.
Environ Technol ; 25(1): 39-49, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15027648

RESUMEN

Results from experiments using an impregnation-reduction (I-R) Pt / Nafion membrane electrode assembly (MEA) in an air fuel cell cathode to remove contaminants (Cu(II), Ni(II), and Fe(III)) from spent chromium electroplating baths are presented in this study. A platinum-carbon (Pt-C) / Nafion MEA and a Pb planar cathode were also used for comparison. The average removal rates of Cu(II) and Ni(II) were almost the same (0.39 and 0.40 mM hr(-1) (or 0.117 and 0.12 mmol hr(-1)), respectively) but higher than that of Fe(III) (0.16 mM hr(-1), or 0.048 mmol hr(-1)) in accordance with the Nernst-Planck flux equation. The removal rates for the same cation were independent of the cathode used. The average removal rate of each impurity was approximately proportional to the product of its initial concentration and separator area/anolyte volume ratio using Pb cathodes. Under constant current conditions the system using the Pt-C / Nafion cathode needed the highest cell voltage, about 3 V more than needed for the system with the Pt / Nafion cathode. The cell voltage required using the Pt / Nafion cathode was similar to that using the conventional planar Pb cathode. Analyses of cathode deposits by SEM/EDS and XPS techniques indicated they were minimal on the Pb and Pt / Nafion cathode and more apparent on the Pt-C / Nafion cathode. The primary deposits on the Pb cathode were chromium oxides (e.g., Cr2O3) with minor amount of lead chromate (lead dichromate or lead trichromate) and other chromium solids (Cr black). As expected, the dominant deposit on the lead anode surface was PbO2.


Asunto(s)
Compuestos de Cromo/química , Cobre/aislamiento & purificación , Galvanoplastia , Hierro/aislamiento & purificación , Níquel/aislamiento & purificación , Carcinógenos Ambientales/química , Cromo/química , Cobre/química , Electrodos , Contaminantes Ambientales/aislamiento & purificación , Hierro/química , Níquel/química
8.
Eur Respir J ; 22(1): 28-34, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12882447

RESUMEN

The current authors have previously identified BR22, a thyroid transcription factor (TTF)-1 associated protein 26 (TAP26), which interacts with TTF-1 to enhance human surfactant protein (SP)-B promoter activity in transfected 293 cells. However, the expression of TAP26 in the lung cells and its biological relevance to the SP-B production under physiological conditions were not examined. In this study, endogenous co-immunoprecipitation and in situ immunohistochemical staining techniques were employed to explore the presence of TAP26 and TTF-1 complex in the lung epithelial cells. The correlation of TAP26, TTF-1 and SP-B expression was inspected in H441 cells in the presence of dexamethasone, a known positive effector of the SP-B promoter. Monoclonal antibody (mAb) against TAP26 can co-immunoprecipitate both TAP26 and TTF-1 from H441 cells. Using this antibody in in situ staining of human lung sections, the data show that TAP26 is present in the lung alveolar epithelial cells. Reverse transcriptase-polymerase chain reaction and Western blot analyses of type-II cells as well as dexamethasone-treated H441 cells suggest that TAP26 expression is modulated coordinately with SP-B and TTF-1 in these cells. In summary, the current study demonstrates that thyroid transcription factor-1 associated protein 26 is an associated protein of thyroid transcription factor-1 in the lung alveolar epithelial cells where surfactant protein gene expressions take place in vivo.


Asunto(s)
Proteínas Nucleares/metabolismo , Alveolos Pulmonares/metabolismo , Surfactantes Pulmonares/metabolismo , Factores de Transcripción/metabolismo , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales , Secuencia de Bases , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Regulación de la Expresión Génica , Biblioteca de Genes , Humanos , Técnicas para Inmunoenzimas , Ratones , Proteínas Nucleares/genética , Alveolos Pulmonares/citología , Homología de Secuencia de Aminoácido , Factores de Transcripción/genética
9.
Genetics ; 159(3): 1339-50, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11729174

RESUMEN

Polyploidy has been recognized as an important step in the evolutionary diversification of flowering plants and may have a significant impact on plant breeding. Statistical analyses for linkage mapping in polyploid species can be difficult due to considerable complexities in polysomic inheritance. In this article, we develop a novel statistical method for linkage analysis of polymorphic markers in a full-sib family of autotetraploids. This method is established on multivalent pairings of homologous chromosomes at meiosis and can provide a simultaneous maximum-likelihood estimation of the double reduction frequencies of and recombination fraction between two markers. The EM algorithm is implemented to provide a tractable way for estimating relative proportions of different modes of gamete formation that generate identical gamete genotypes due to multivalent pairings. Extensive simulation studies were performed to demonstrate the statistical properties of this method. The implications of the new method for understanding the genome structure and organization of polyploid species are discussed.


Asunto(s)
Ligamiento Genético , Modelos Genéticos , Ploidias , Algoritmos , Marcadores Genéticos , Genotipo , Funciones de Verosimilitud , Meiosis , Modelos Estadísticos , Polimorfismo Genético , Recombinación Genética
10.
J Biol Chem ; 276(30): 27907-12, 2001 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-11353774

RESUMEN

In a search for novel transcriptional intermediary factors for the estrogen receptor (ER), we used the ligand-binding domain and hinge region of ER as bait in a yeast two-hybrid screen of a cDNA library derived from tamoxifen-resistant MCF-7 human breast tumors from an in vivo athymic nude mouse model. Here we report the isolation and characterization of the forkhead homologue in rhabdomyosarcoma (FKHR), a recently described member of the hepatocyte nuclear factor 3/forkhead homeotic gene family, as a nuclear hormone receptor (NR) intermediary protein. FKHR interacts with both steroid and nonsteroid NRs, although the effect of ligand on this interaction varies by receptor type. The interaction of FKHR with ER is enhanced by estrogen, whereas its interaction with thyroid hormone receptor and retinoic acid receptor is ligand-independent. In addition, FKHR differentially regulates the transactivation mediated by different NRs. Transient transfection of FKHR into mammalian cells dramatically represses transcription mediated by the ER, glucocorticoid receptor, and progesterone receptor. In contrast, FKHR stimulates rather than represses retinoic acid receptor- and thyroid hormone receptor-mediated transactivation. Most intriguingly, overexpression of FKHR dramatically inhibits the proliferation of ER-dependent MCF-7 breast cancer cells. Therefore, FKHR represents a bifunctional NR intermediary protein that can act as either a coactivator or corepressor, depending on the receptor type.


Asunto(s)
Núcleo Celular/metabolismo , Proteínas de Unión al ADN/química , Rabdomiosarcoma/metabolismo , Factores de Transcripción/química , Secuencia de Aminoácidos , Animales , Western Blotting , Neoplasias de la Mama/metabolismo , Células COS , ADN Complementario/metabolismo , Proteína Forkhead Box O1 , Factores de Transcripción Forkhead , Biblioteca de Genes , Glutatión Transferasa/metabolismo , Humanos , Ligandos , Luciferasas/metabolismo , Ratones , Ratones Desnudos , Datos de Secuencia Molecular , Plásmidos/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Receptores de Estrógenos/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Homología de Secuencia de Aminoácido , Transducción de Señal , Distribución Tisular , Activación Transcripcional , Transfección , Células Tumorales Cultivadas , Técnicas del Sistema de Dos Híbridos
11.
J Clin Oncol ; 19(2): 551-7, 2001 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-11208850

RESUMEN

PURPOSE: Lesion volume is often used as an end point in clinical trials of oncology therapy. We sought to compare the common method of using orthogonal diameters to estimate lesion volume (the diameter method) with a computer-assisted planimetric technique (the perimeter method). METHODS: Radiologists reviewed 825 magnetic resonance imaging studies from 219 patients with glioblastoma multiforme. Each study had lesion volume independently estimated via the diameter and perimeter methods. Cystic areas were subtracted out or excluded from the outlined lesion. Inter- and intrareader variability was measured by using multiple readings on 48 cases. Where serial studies were available in noncystic cases, a mock response analysis was used. RESULTS: The perimeter method had a reduced interreader and intrareader variability compared with the diameter method (using SD of differences): intrareader, 1.76 mL v 7.38 mL (P < .001); interreader, 2.51 mL v 9.07 mL (P < .001) for perimeter and diameter results, respectively. Of the 121 noncystic cases, 23 had serial data. In six (26.1%) of those 23, a classification difference occurred when the perimeter method was used versus the diameter method. CONCLUSION: Variability of measurements was reduced with the computer-assisted perimeter method compared with the diameter method, which suggests that changes in volume can be detected more accurately with the perimeter method. The differences between these techniques seem large enough to have an impact on grading the response to therapy.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Encéfalo/patología , Glioblastoma/diagnóstico , Imagen por Resonancia Magnética , Análisis Numérico Asistido por Computador , Humanos , Modelos Teóricos , Variaciones Dependientes del Observador
12.
Am J Respir Cell Mol Biol ; 24(1): 30-37, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11152647

RESUMEN

Surfactant protein (SP)-B expression is restricted to type II pneumocytes and Clara cells in the lung. Previously, a promoter region of human SP-B gene from -64 to -118 has been identified as critical for the tissue-specific expression of this gene. Two cis-elements for thyroid transcription factor (TTF)-1 and hepatocyte nuclear factor (HNF)-3alpha binding were found within this area. Using an oligonucleotide fragment, we incorporated this region sequence into the promoter of a HIS3 reporter gene in yeast. With this modified yeast a human lung complementary DNA (cDNA) library was screened for DNA-binding proteins, other than TTF-1 and HNF-3alpha, that interacted with this promoter segment. A cDNA clone encoding a novel polypeptide, BR22, was identified that activated the reporter gene expression in yeast. This gene is expressed in many tissues and encodes a protein with bipartite nuclear localization signals. Studies using in vivo yeast two-hybrid analysis, in vitro protein-protein interactions, and coimmunoprecipitation analyses demonstrated that BR22 formed a protein complex with TTF-1. In vivo cotransfection studies further indicated that BR22 could act with TTF-1 to synergistically activate the SP-B promoter in mammalian cells. Our data suggest that BR22 is a TTF-1-associated protein. Through a protein-protein interaction with TTF-1, BR22 can form a complex and activate the human SP-B promoter in vivo.


Asunto(s)
Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Regiones Promotoras Genéticas/genética , Proteolípidos/genética , Surfactantes Pulmonares/genética , Factores de Transcripción/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión/genética , Biblioteca de Genes , Genes Reporteros , Humanos , Pulmón , Especificidad de Órganos/genética , Pruebas de Precipitina , Unión Proteica/genética , Proteolípidos/metabolismo , Surfactantes Pulmonares/metabolismo , Secuencias Reguladoras de Ácidos Nucleicos/genética , Homología de Secuencia de Aminoácido , Factor Nuclear Tiroideo 1 , Activación Transcripcional/genética , Transfección , Técnicas del Sistema de Dos Híbridos
13.
J Biol Chem ; 275(47): 37150-8, 2000 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-10973948

RESUMEN

Protein methylation reactions can play important roles in cell physiology. After labeling intact Saccharomyces cerevisiae cells with S-adenosyl-l-[methyl-(3)H]methionine, we identified a major methylated 49-kDa polypeptide containing [(3)H]methyl groups in two distinct types of linkages. Peptide sequence analysis of the purified methylated protein revealed that it is eukaryotic elongation factor 1A (eEF1A, formerly EF-1alpha), the protein that forms a complex with GTP and aminoacyl-tRNAs for binding to the ribosomal A site during protein translation. Previous studies have shown that eEF1A is methylated on several internal lysine residues to give mono-, di-, and tri-N-epsilon-methyl-lysine derivatives. We confirm this finding but also detect methylation that is released as volatile methyl groups after base hydrolysis, characteristic of ester linkages. In cycloheximide-treated cells, methyl esterified eEF1A was detected largely in the ribosome and polysome fractions; little or no methylated protein was found in the soluble fraction. Because the base-labile, volatile [methyl-(3)H]radioactivity of eEF1A could be released by trypsin treatment but not by carboxypeptidase Y or chymotrypsin treatment, we suggest that the methyl ester is present on the alpha-carboxyl group of its C-terminal lysine residue. From the results of pulse-chase experiments using radiolabeled intact yeast cells, we find that the N-methylated lysine residues of eEF1A are stable over 4 h, whereas the eEF1A carboxyl methyl ester has a half-life of less than 10 min. The rapid turnover of the methyl ester suggests that the methylation/demethylation of eEF1A at the C-terminal carboxyl group may represent a novel mode of regulation of the activity of this protein in yeast.


Asunto(s)
Factor 1 de Elongación Peptídica/biosíntesis , Catálisis , Cromatografía por Intercambio Iónico , Cicloheximida/farmacología , Hidrólisis , Metilación , Peso Molecular , Factor 1 de Elongación Peptídica/química , Procesamiento Proteico-Postraduccional , Inhibidores de la Síntesis de la Proteína/farmacología , Ribosomas/metabolismo , Saccharomyces cerevisiae
14.
Diabetes ; 49(3): 492-9, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10868973

RESUMEN

Polymorphic markers within the CTLA4 gene on chromosome 2q33 have been shown to be associated with type 1 diabetes. Therefore, a gene responsible for the disease (IDDM12) most likely lies within a region of <1-2 cM of CTLA4. To define more precisely the IDDM12 interval, we genotyped a multiethnic (U.S. Caucasian, Mexican-American, French, Spanish, Korean, and Chinese) collection of 178 simplex and 350 multiplex families for 10 polymorphic markers within a genomic interval of approximately 300 kb, which contains the candidate genes CTLA4 and CD28. The order of these markers (D2S346, CD28, GGAA19E07, D2S307, D2S72, CTLA4, D2S105, and GATA52A04) was determined by sequence tagged site content mapping of bacterial artificial chromosome (BAC) and yeast artificial chromosome (YAC) clones. The transmission disequilibrium test (TDT) analyses of our data revealed significant association/linkage with three markers within CTLA4 and two immediate flanking markers (D2S72 and D2S105) on each side of CTLA4 but not with more distant markers including the candidate gene CD28. Tsp analyses revealed significant association only with the three polymorphic markers within the CTLA4 gene. The markers linked and associated with type 1 diabetes are contained within a phagemid artificial chromosome clone of 100 kb, suggesting that the IDDM12 locus is either CTLA4 or an unknown gene in very close proximity.


Asunto(s)
Mapeo Cromosómico , Cromosomas Artificiales de Levadura/genética , Cromosomas Bacterianos/genética , Cromosomas Humanos Par 2/genética , ADN Recombinante/genética , Diabetes Mellitus Tipo 1/genética , Predisposición Genética a la Enfermedad/genética , Inmunoconjugados , Abatacept , Antígenos CD , Antígenos de Diferenciación/genética , Antígeno CTLA-4 , Clonación Molecular , Ligamiento Genético , Marcadores Genéticos , Haplotipos , Humanos , Lugares Marcados de Secuencia , Repeticiones de Trinucleótidos/genética
15.
Pharmacol Toxicol ; 87(6): 286-91, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11140828

RESUMEN

The hepatic disposition of pesticides and neurotoxins may influence susceptibility to Parkinson's disease. Therefore we examined the behaviour of paraquat, dichlorodiphenyltrichloroethane (DDT), malathion and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in perfused rat liver using the multiple indicator-dilution technique. The values for the recovery of paraquat, DDT, malathion and MPTP were 1.05+/-0.12, 0.32+/-0.01, 0.11+/-0.02 and 0.02+/-0.01, respectively. The volumes of distribution were 0.28+/-0.13, 0.69+/-0.12, 3.30+/-0.58 and 5.10+/-6.00 ml/g, respectively. The permeability-surface area products suggest that transport of DDT and MPTP across cell membranes is by simple diffusion. However, there may be a specific influx mechanism for malathion and a specific efflux mechanism for paraquat. There is considerable variability in the hepatic disposition of putative neurotoxins such as MPTP and pesticides. Factors that influence the hepatic disposition of neurotoxins may alter susceptibility to neurotoxic diseases however the effects will be diverse.


Asunto(s)
Hígado/metabolismo , Neurotoxinas/farmacocinética , Plaguicidas/farmacocinética , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/farmacocinética , Animales , Transporte Biológico/efectos de los fármacos , DDT/farmacocinética , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Humanos , Malatión/farmacocinética , Masculino , Paraquat/farmacocinética , Enfermedad de Parkinson/metabolismo , Perfusión , Ratas , Ratas Wistar , Distribución Tisular
16.
Microvasc Res ; 55(3): 201-14, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9657920

RESUMEN

In a novel assay of angiogenesis in the quail chorioallantoic membrane (CAM), we measured vascular pattern and angiogenic rate after homogeneous exposure of the entire vascular tree to recognized modulators of vessel growth. In comparison to phosphate-buffered saline (PBS)-treated controls, the vascular stimulator, basic fibroblast growth factor (bFGF or FGF-2), increased the rate of angiogenesis by a maximum of 72%, whereas a recently discovered angiogenic inhibitor, angiostatin, decreased the rate of vascular growth by a maximum of 68%. The perturbants were applied in PBS to the CAM of 7-day-old embryos (E7) cultured in petri dishes, and the embryos were cultured further until fixation at E8 or E9. For morphometry of the quasi-two-dimensional CAM vasculature, digital images of arterial endpoints from the middle region of the CAM were acquired in grayscale at a magnification of 10x, binarized to black/white, and skeletonized. The pattern of vessel branching was assessed by measurement of the fractal dimension (Df), and vessel density (rhov), with the method of grid intersection. Correlations between these two statistical techniques were linear (r2 ranged from 0.967 to 0.985). For skeletonized images at E9, Df and rhov of bFGF-treated samples were 1.55 +/- 0.01 and 782 +/- 26/cm2, respectively (relative to 1.49 +/- 0.02 and 583 +/- 60/cm2 for controls), and of angiostatin-treated samples, 1.43 +/- 0.02 and 424 +/- 74/cm2 (relative to 1.50 +/- 0.02 and 616 +/- 59/cm2 for controls). To establish normalization values for rates of angiogenesis, we analyzed untreated CAMs of E6 to E12. From E7 to E10 in skeletonized images, Df increased linearly from 1.37 +/- 0.01 to 1.54 +/- 0.01 and rhov from 311 +/- 67 to 746 +/- 124/cm2 (in both cases, r2 = 1.000). Thus, the rates of normal angiogenic growth as measured by Df and rhov were 0.06/day and 138/cm2-day, respectively. From E10 to E12, Df and rhov declined slightly. Differences between the vasculature of untreated and PBS-treated CAMs were statistically insignificant. In conclusion, vascular branching pattern and density in the quail CAM were stimulated by bFGF and inhibited by angiostatin. We quantified these changes with statistical significance by Df and rhov, which are expressed relative to the rates of normal developmental angiogenesis measured for the two parameters in untreated quail embryos.


Asunto(s)
Alantoides/irrigación sanguínea , Corion/irrigación sanguínea , Coturnix/embriología , Factor 2 de Crecimiento de Fibroblastos/farmacología , Neovascularización Fisiológica/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Plasminógeno/farmacología , Alantoides/efectos de los fármacos , Angiostatinas , Animales , Antineoplásicos/farmacología , Pollos , Corion/efectos de los fármacos , Endotoxinas/farmacología , Fractales , Procesamiento de Imagen Asistido por Computador , Ovalbúmina/farmacología
17.
Proc Natl Acad Sci U S A ; 94(22): 12075-80, 1997 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-9342365

RESUMEN

Germ-line mutations of the BRCA1 gene predispose women to early-onset breast and ovarian cancer by compromising the gene's presumptive function as a tumor suppressor. Although the biochemical properties of BRCA1 polypeptides are not understood, their expression pattern and subcellular localization suggest a role in cell-cycle regulation. When resting cells are induced to proliferate, the steady-state levels of BRCA1 increase in late G1 and reach a maximum during S phase. Moreover, in S phase cells, BRCA1 polypeptides are hyperphosphorylated and accumulate into discrete subnuclear foci termed "BRCA1 nuclear dots." BRCA1 associates in vivo with a structurally related protein termed BARD1. Here we show that the steady-state levels of BARD1, unlike those of BRCA1, remain relatively constant during cell cycle progression. However, immunostaining revealed that BARD1 resides within BRCA1 nuclear dots during S phase of the cell cycle, but not during the G1 phase. Nevertheless, BARD1 polypeptides are found exclusively in the nuclear fractions of both G1- and S-phase cells. Therefore, progression to S phase is accompanied by the aggregation of nuclear BARD1 polypeptides into BRCA1 nuclear dots. This cell cycle-dependent colocalization of BARD1 and BRCA1 indicates a role for BARD1 in BRCA1-mediated tumor suppression.


Asunto(s)
Proteína BRCA1/aislamiento & purificación , Proteínas Portadoras/aislamiento & purificación , Ciclo Celular , Núcleo Celular/ultraestructura , Proteínas Supresoras de Tumor , Ubiquitina-Proteína Ligasas , Mama/citología , Compartimento Celular , Células Epiteliales , Femenino , Técnica del Anticuerpo Fluorescente , Fase G1 , Humanos , Fase S
18.
Hum Mol Genet ; 6(8): 1275-82, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9259273

RESUMEN

Linkage disequilibrium (association) analysis was used to evaluate a candidate region near the CTLA4/CD28 genes using a multi-ethnic collection of families with one or more children affected by IDDM. In the data set unique to this study (Spanish, French, Mexican-American, Chinese and Korean), the transmission/disequilibrium test (TDT) revealed a highly significant deviation for transmission of alleles at the (AT)n microsatellite marker in the 3' untranslated region (P = 0.002) and the A/G polymorphism in the first exon (P = 0.00002) of the CTLA4 gene. The overall evidence for transmission deviation of the CTLA4 A/G alleles is also highly significant (P = 0.00005) in the combined data set (669 multiplex and 357 simplex families) from this study and a previous report on families from USA, Italy, UK, Spain and Sardinia. Significant heterogeneity was observed in these data sets. The British, Sardinian and Chinese data sets did not show any deviation for the A/G polymorphism, while the Caucasian-American data set showed a weak transmission deviation. Strong deviation for transmission was seen in the three Mediterranean-European populations (Italian, Spanish and French) (P = 10(-5)), the Mexican-American population (P = 0.002) and the Korean population (P = 0.03). These results suggest that a true IDDM susceptibility locus (designated IDDM12) is located near CTLA4.


Asunto(s)
Antígenos de Diferenciación/genética , Diabetes Mellitus Tipo 1/etnología , Diabetes Mellitus Tipo 1/genética , Inmunoconjugados , Polimorfismo Genético , Abatacept , Alelos , Antígenos CD , Antígeno CTLA-4 , Estudios de Casos y Controles , Etnicidad/genética , Humanos , Desequilibrio de Ligamiento , Repeticiones de Microsatélite
19.
Nucleic Acids Res ; 25(12): 2284-92, 1997 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-9171077

RESUMEN

NonO is an unusual nucleic acid binding protein not only in that it binds both DNA and RNA but that it does so via functionally separable domains. Here we document that NonO enhances the binding of some (E47, OTF-1 and OTF-2) but not all (PEA3) conventional sequence-specific transcription factors to their recognition sites in artificial substrates as well as in an immunoglobulin VHpromoter. We also show that NonO induces the binding of the Ku complex to DNA ends. Ku has no known DNA sequence specificity. These enhancement of binding effects are NonO concentration dependent. Using the E box activity of E47 as a model, kinetic studies demonstrate that the association rate of the protein-DNA complex increases in the presence of NonO while the dissociation rate remains the same, thereby increasing the sum total of the interaction. Oligo competition experiments indicate that NonO does not contact the target DNA in order to enhance the binding activity of DNA binding proteins. Rather, methylation interference analysis reveals that the induced E47 binding-activity has the same DNA-binding sequence specificity as the normal binding. This result suggests that one of the effects of NonO is to induce a true protein-DNA interaction. In this way, it might be possible for NonO to play a crucial role in gene regulation.


Asunto(s)
Antígenos Nucleares , ADN Helicasas , Proteínas de Unión al ADN/metabolismo , ADN/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas de Saccharomyces cerevisiae , Factores de Transcripción/metabolismo , Sitios de Unión , Ciclina D1 , ADN/química , Metilación de ADN , Proteínas de Unión al ADN/biosíntesis , Regulación de la Expresión Génica , Genes de Inmunoglobulinas , Glutatión Transferasa , Factor C1 de la Célula Huésped , Cadenas Pesadas de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Cinética , Autoantígeno Ku , Proteínas Nucleares/metabolismo , Factor 1 de Transcripción de Unión a Octámeros , Sondas de Oligonucleótidos , Pichia , Reacción en Cadena de la Polimerasa , Regiones Promotoras Genéticas , Biosíntesis de Proteínas , Proteínas de Unión al ARN/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , Factores de Transcripción/biosíntesis , Transcripción Genética
20.
J Hepatol ; 26(2): 376-81, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9059960

RESUMEN

BACKGROUND/AIMS: Venous hyporesponsiveness in portal hypertension has been reported previously by us. The present study was undertaken to investigate possible changes of phosphoinositide signal transduction pathway in the portal veins from portal hypertensive rats METHODS: Portal hypertension was induced by partial portal vein ligation. Fourteen days after surgery, portal veins were removed for measurement of [3H]inositol phosphate responses to both receptor- and nonreceptor-mediated stimuli. RESULTS: Basal [3H]inositol phosphate formation was similar between the two groups. Both phenylephrine and angiotensin II stimulated [3H]inositol phosphate formation in portal veins, but the responses were attenuated in the portal hypertensive group. In contrast, the [3H]inositol phosphate formation by nonreceptor-mediated stimuli (GTP gamma S, NaF/AlCl3, and phospholipase C) was similar between the two groups. CONCLUSION: Our results showed that the receptor-mediated [3H]inositol phosphate formation was attenuated, while the non-receptor-mediated formation was unaltered, in the portal vein from portal hypertensive rats.


Asunto(s)
Hipertensión Portal/metabolismo , Fosfatos de Inositol/biosíntesis , Vena Porta/metabolismo , Angiotensina II/farmacología , Animales , AMP Cíclico/fisiología , Relación Dosis-Respuesta a Droga , Proteínas de Unión al GTP/fisiología , Guanosina 5'-O-(3-Tiotrifosfato)/farmacología , Masculino , Ratas , Ratas Sprague-Dawley
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