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1.
Semin Oncol ; 25(2 Suppl 4): 24-32; discussion 45-8, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9578059

RESUMEN

With the use of a cisplatin-based chemotherapy, metastatic testicular cancer has become a model for a highly curable malignant disease. Current data show that 70% to 80% of patients with this disease will achieve long-term survival following cisplatin/etoposide/bleomycin therapy. The role of high-dose chemotherapy with autologous stem cell support is being investigated in metastatic germ cell cancer in attempts to improve outcome for patients whose disease relapses after standard-dose chemotherapy and for those who present initially with advanced metastatic disease. Prognostic categories for patients receiving high-dose salvage chemotherapy have recently been developed: cisplatin-refractory disease, beta-human chorionic gonadotropin values greater than 1,000 U/L, and primary mediastinal germ cell tumors are factors characterizing patients who will derive less benefit from high-dose chemotherapy than those with chemosensitive disease at relapse. While standard-dose salvage chemotherapy achieves only a 20% long-term survival rate, high-dose salvage chemotherapy may yield a cure rate of approximately 40%. A randomized study comparing high-dose therapy with conventional-dose therapy (IT94 coordinated by the European Group for Blood and Marrow Transplantation) in patients with relapsed disease is ongoing to substantiate this observation. The use of dose-intensive therapy as first-line treatment is currently being studied by several institutions. High-dose therapy may be better tolerated when used first line compared with its use in the salvage situation, and may also achieve a rapid initial cell kill before cytostatic drug resistance develops. The German Testicular Cancer Study Group has developed a sequential high-dose combination regimen of cisplatin/etoposide/ifosfamide given with granulocyte colony-stimulating factor and peripheral blood stem cell support for four cycles every 3 weeks. This ongoing study, started in 1990, had accrued 218 patients with advanced testicular germ cell tumors as of June 1997. Of 141 evaluable patients receiving dose levels 1 through 5, 82 (58%) have achieved complete remission with no evidence of disease and 32 (23%) have achieved partial remission with marker normalization. The early death rate was 8%. Overall and event-free survival rates at 2 years are 78% and 73%, respectively, with a projected 5-year overall survival rate of 74%. Despite favorable preliminary results, this approach cannot be considered standard treatment. Currently, high-dose chemotherapy with peripheral blood stem cell transplantation should be administered to patients with testicular cancer only within controlled clinical trials to allow long-term cure rates and treatment-related late side effects to be evaluated.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Germinoma/tratamiento farmacológico , Germinoma/secundario , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Trasplante de Células Madre Hematopoyéticas , Neoplasias Testiculares/tratamiento farmacológico , Ensayos Clínicos como Asunto , Germinoma/terapia , Humanos , Masculino , Pronóstico , Terapia Recuperativa , Tasa de Supervivencia , Neoplasias Testiculares/terapia
2.
J Hypertens ; 19(11): 1957-64, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11677360

RESUMEN

BACKGROUND: Familial hyperkalaemic hypertension (FHH) is a Mendelian form of low-renin hypertension characterized by hyperkalaemia and hyperchloraemic acidosis despite a normal glomerular filtration rate. To date, three different loci have been identified, on chromosomes 1, 17 and 12. OBJECTIVE: To test for genetic linkage between the three FHH loci and three new affected kindreds. DESIGN AND METHODS: Clinical, biological and genetic analyses were made of three kindreds, including 11 affected individuals among 25 members. Genotyping was performed using four series of microsatellite markers spanning the chromosomes 1, 17 and 12 loci, and the thiazide-sensitive Na-Cl cotransporter (SLC12A3) gene. RESULTS: Segregation of the trait in each kindred was compatible with an autosomal transmission, the affected individuals displaying reasonably consistent biochemical abnormalities and the expected variability in arterial hypertension. Multipoint linkage analysis excluded linkage with the four candidate loci in kindreds 1 and 2, but not with the chromosome 1 locus in kindred 3. CONCLUSION: These results demonstrate further genetic heterogeneity and that a fourth gene is responsible for FHH in at least two unrelated kindreds. They suggest a variety of molecular defects leading to FHH.


Asunto(s)
Variación Genética , Hiperpotasemia/complicaciones , Hipertensión/etiología , Hipertensión/genética , Receptores de Droga , Simportadores , Adolescente , Adulto , Anciano , Proteínas Portadoras/genética , Niño , Mapeo Cromosómico , Cromosomas Humanos Par 1/genética , Cromosomas Humanos Par 12/genética , Cromosomas Humanos Par 17/genética , Femenino , Ligamiento Genético , Genotipo , Humanos , Lactante , Masculino , Persona de Mediana Edad , Linaje , Seudohipoaldosteronismo/clasificación , Seudohipoaldosteronismo/genética , Simportadores del Cloruro de Sodio , Miembro 3 de la Familia de Transportadores de Soluto 12
3.
J Hypertens ; 15(12 Pt 2): 1797-801, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9488242

RESUMEN

OBJECTIVE: To describe phenotypes and estimate the prevalence of familial cases of renal artery fibromuscular dysplasia (FMD). PATIENTS AND SETTING: One hundred and four unrelated hypertensive patients (94 women) with renal artery fibromuscular dysplasia documented on angiography and classified as having multifocal or unifocal lesions. Familial cases were defined as those with angiographic evidence of renal artery FMD in at least one sibling. RESULTS: Eighty-one patients had multifocal and 16 had unifocal FMD. Both types of stenosis were present in seven patients. Fifty-four patients had bilateral FMD, including the seven patients with both unifocal and multifocal lesions. The 16 patients with unifocal FMD were younger, more likely to be men, and more commonly had unilateral stenoses, stenoses exceeding 75% and a small ischemic kidney than the 81 patients with multifocal lesions. Eleven cases were identified as familial on the basis of FMD having been documented in at least one sibling (eight sibling pairs and three trios). All probands were women and exhibited multifocal lesions. FMD was more often bilateral in familial than it was in apparently sporadic cases. CONCLUSIONS: Multifocal FMD was mostly found in women and unifocal FMD in young men with more severe stenosis and kidney ischemia. The documented prevalence of familial cases was 11% in this series, the true prevalence being probably higher because only a few siblings were examined by angiography. Familial cases all exhibited the multifocal type and were more commonly bilateral than were sporadic cases.


Asunto(s)
Displasia Fibromuscular/genética , Obstrucción de la Arteria Renal/genética , Angiografía , Femenino , Displasia Fibromuscular/complicaciones , Displasia Fibromuscular/diagnóstico por imagen , Pruebas Genéticas , Humanos , Hipertensión Renal/genética , Isquemia/diagnóstico por imagen , Isquemia/etiología , Riñón/irrigación sanguínea , Masculino , Persona de Mediana Edad , Linaje , Fenotipo , Obstrucción de la Arteria Renal/complicaciones , Obstrucción de la Arteria Renal/diagnóstico por imagen , Estudios Retrospectivos
4.
FEMS Microbiol Lett ; 141(2-3): 129-37, 1996 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-8768514

RESUMEN

The nucleotide sequence of a new Bacillus subtilis gene (amhX) was determined that encodes a protein (AmhX) with strong sequence identity to amidohydrolases from both plant and bacterial species and a carboxypeptidase from the archaeon Sulfolobus sulfataricus. The amhX gene encodes a hydrophilic polypeptide of 383 amino acids with a molecular mass of 41.5 kDa. The amhX gene was overexpressed in E. coli by using the T7 RNA polymerase/promoter system and the transcription initiation sites for the amhX mRNAs in B. subtilis were determined by primer extension analysis. Chromosomal amhX mutations were constructed by marker replacement and the amhX gene was positioned at 25 degrees on the genetic and physical map of the B. subtilis chromosome.


Asunto(s)
Amidohidrolasas/genética , Bacillus subtilis/genética , Mapeo Cromosómico , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Secuencia de Bases , Clonación Molecular , Expresión Génica , Datos de Secuencia Molecular , Proteínas de Plantas/genética , Homología de Secuencia de Aminoácido
5.
Arch Mal Coeur Vaiss ; 93(11 Suppl): 1469-73, 2000 Nov.
Artículo en Francés | MEDLINE | ID: mdl-11190297

RESUMEN

Hypokalaemic hypertension or resistant hypertension justify investigation for primary hyperaldosteronism. The first step of this investigation is to exclude the ingestion of liquorice, alkalis and diuretics. The second is to make sure that the treatment is compatible with the hormonal tests and that the natriuresis and kaliuresis are normal. The diagnosis then depends on an increased plasma or urinary concentration of aldosterone with a low plasma renin activity. The adenoma of Conn is present in 2/3 of cases and surgically curable, and should be distinguished from adrenal hyperplasia which is treatable with distal diuretics. This is a diagnosis which requires computerised tomography or, when inconclusive, demonstration of unilateral secretion of aldosterone. Adrenalectomy, usually by coelioscopy, is indicated in Conn's adenoma when the patient is young and the hypertension severe or recent. Surgical abstention is strongly advised in cases of adrenal hyperplasia.


Asunto(s)
Enfermedades de las Glándulas Suprarrenales/complicaciones , Hiperaldosteronismo/complicaciones , Hipertensión/tratamiento farmacológico , Adenoma/complicaciones , Adenoma/diagnóstico , Adenoma/terapia , Enfermedades de las Glándulas Suprarrenales/diagnóstico , Enfermedades de las Glándulas Suprarrenales/terapia , Adulto , Factores de Edad , Anciano , Diagnóstico Diferencial , Humanos , Hiperaldosteronismo/diagnóstico , Hiperaldosteronismo/terapia , Persona de Mediana Edad , Renina/metabolismo
6.
Arch Mal Coeur Vaiss ; 91(8): 1069-71, 1998 Aug.
Artículo en Francés | MEDLINE | ID: mdl-9749167

RESUMEN

The aim of this study was to conduct a formal pedigree analysis of the involvement of the elastin gene in families. From 140 subjects with renal FMD documented on angiography, family cases with documented renal artery fibromuscular dysplasia (FMD) and to test pedigrees were constructed and familial cases defined by angiographic evidence of FMD in at least one sibling. Familial screening was made either by echodoppler for asymptomatic subjects or by digital intravenous angiography for hypertensive subjects. Linkage analysis at the elastin gene locus was performed in these families with two polymorphic markers: one diallelic RFLP located in exon 16 and one multiallelic CA repeat located in intron 17 of the elastin gene. Fourteen pedigrees (10%) were obtained including nine sibling pairs, four trios and one vertical transmission from a father to his daughter. Most affected subjects were females (84%) but familial cases were more frequently bilateral than sporadic cases (80% vs 49%, p = 0.07). Pedigrees analysis was compatible with an autosomal dominant mode of inheritance and suggested in these families an age and sex-dependent incomplete penetrance model. Linkage analysis resulted in a maximum two-point lod score of 0.06 at theta = 0.20 using the dinucleotide CA repeat. Analysis of the diallelic marker revealed similar frequencies in affected and non affected subjects. This study highlights the role of genetics factors in approximately 10% of FMD cases. The elastin gene does not seem to be involved in the pathogenesis of FMD.


Asunto(s)
Elastina/genética , Displasia Fibromuscular/genética , Obstrucción de la Arteria Renal/genética , Adulto , Anciano , Femenino , Ligamiento Genético , Marcadores Genéticos , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Linaje , Polimorfismo de Longitud del Fragmento de Restricción
7.
Presse Med ; 31(8): 371-8, 2002 Mar 02.
Artículo en Francés | MEDLINE | ID: mdl-11913083

RESUMEN

EXTENSIVE AND COSTLY INVESTIGATIONS: Are not warranted in the vast majority of hypertensive patients. Characteristics identifying the patients at risk for secondary hypertension can be used to define the small percentage of patients with hypertension who require more extensive diagnostic testing and management of their condition. Exposure to certain medicines, foods or drugs may cause reversible rises in blood pressure. Renovascular and adrenal diseases cause curable forms of hypertension. IN MANY CASES, THE PATIENT'S HISTORY: Examination and simple tests can detect such exposures and disorders. Checking for secondary hypertension is therefore an early step required for the management of all patients with hypertension, provided it is based on clinical signs and inexpensive tests. This primary screening cannot exclude the possibility of renovascular or adrenal disease in a small number of asymptomatic patients. The risk of missing a diagnosis is acceptable provided that blood pressure is normalized by non-specific antihypertensive treatment. However, more extensive etiologic investigation is required in patients who subsequently develop resistant hypertension. This secondary screening requires imaging and biochemical tests that are not required for primary screening. CORRECTION OF THE CAUSES: Of secondary forms of hypertension may restore blood pressure to normal. The patient's age affects the reversibility of renovascular and adrenal hypertension after etiologic treatment: the younger the patient, the higher the probability of blood pressure normalization.


Asunto(s)
Enfermedades de las Glándulas Suprarrenales/diagnóstico , Hipertensión Renovascular/diagnóstico , Hipertensión/etiología , Adenoma/complicaciones , Adenoma/diagnóstico , Adenoma/cirugía , Enfermedades de las Glándulas Suprarrenales/cirugía , Enfermedades de las Glándulas Suprarrenales/terapia , Neoplasias de las Glándulas Suprarrenales/complicaciones , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Neoplasias de las Glándulas Suprarrenales/cirugía , Adulto , Factores de Edad , Anciano , Antihipertensivos/uso terapéutico , Diagnóstico Diferencial , Femenino , Humanos , Hiperaldosteronismo/complicaciones , Hiperaldosteronismo/diagnóstico , Hipertensión/diagnóstico , Hipertensión/terapia , Hipertensión Renovascular/terapia , Enfermedad Iatrogénica , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Feocromocitoma/complicaciones , Feocromocitoma/diagnóstico , Feocromocitoma/cirugía , Estudios Prospectivos , Diálisis Renal , Factores de Riesgo
8.
Handchir Mikrochir Plast Chir ; 45(5): 287-92, 2013 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-24089304

RESUMEN

Hidradenocarcinomas are rare, yet highly malignant tumors of eccrine sweat gland origin. Due to its locally aggressive growth and likelihood for metastasis it should be considered as a differential diagnosis especially in case of suspicious intraoperative findings. We report the case of a 73-year-old female patient presenting with a hidradenocarcinoma of the wrist. Treatment of hidradenocarcinomas is similar to the treatment of sarcomas: The first step is an incisional biopsy and obtaining an expert second opinion on the histopathological diagnosis as well as staging. The second step is a clear margin resection of the tumor and the plastic-surgical reconstruction. A long-term follow-up is mandatory to detect potential recurrence or metastasis.


Asunto(s)
Acrospiroma/cirugía , Neoplasias de las Glándulas Sudoríparas/cirugía , Muñeca/cirugía , Acrospiroma/diagnóstico , Acrospiroma/patología , Anciano , Biopsia , Transformación Celular Neoplásica/patología , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Estadificación de Neoplasias , Complicaciones Posoperatorias/etiología , Rango del Movimiento Articular/fisiología , Derivación y Consulta , Colgajos Quirúrgicos/cirugía , Neoplasias de las Glándulas Sudoríparas/diagnóstico , Neoplasias de las Glándulas Sudoríparas/patología , Muñeca/patología
12.
J Biol Chem ; 270(28): 16701-13, 1995 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-7622480

RESUMEN

Exogenously provided glycine betaine can efficiently protect Bacillus subtilis from the detrimental effects of high osmolarity environments. Through functional complementation of an Escherichia coli mutant deficient in glycine betaine uptake with a gene library from B. subtilis, we have identified a multicomponent glycine betaine transport system, OpuA. Uptake of radiolabeled glycine betaine in B. subtilis was found to be osmotically stimulated and was strongly decreased in a mutant strain lacking the OpuA transport system. DNA sequence analysis revealed that the components of the OpuA system are encoded by anoperon (opuA) comprising three structural genes: opuAA, opuAB, and opuAC. The products of these genes exhibit features characteristic for binding protein-dependent transport systems and in particular show homology to the glycine betaine uptake system ProU from E. coli. Expression of the opuA operon is under osmotic control. The transcriptional initiation sites of opuA were mapped by high resolution primer extension analysis, and two opuA mRNAs were detected that differed by 38 base pairs at their 5' ends. Synthesis of the shorter transcript was strongly increased in cells grown at high osmolarity, whereas the amount of the longer transcript did not vary in response to medium osmolarity. Physical and genetic mapping experiments allowed the positioning the opuA operon at 25 degrees on the genetic map of B. subtilis.


Asunto(s)
Bacillus subtilis/metabolismo , Proteínas Bacterianas/metabolismo , Betaína/metabolismo , Proteínas Portadoras/metabolismo , Lipoproteínas/metabolismo , Equilibrio Hidroelectrolítico , Secuencia de Aminoácidos , Proteínas Bacterianas/análisis , Proteínas Bacterianas/genética , Secuencia de Bases , Transporte Biológico , Proteínas Portadoras/análisis , Proteínas Portadoras/genética , Mapeo Cromosómico , Clonación Molecular , Lipoproteínas/análisis , Lipoproteínas/genética , Datos de Secuencia Molecular , Operón
13.
Arch Microbiol ; 170(5): 319-30, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9818351

RESUMEN

All microorganisms possess a positive turgor, and maintenance of this outward-directed pressure is essential since it is generally considered as the driving force for cell expansion. Exposure of microorganisms to high-osmolality environments triggers rapid fluxes of cell water along the osmotic gradient out of the cell, thus causing a reduction in turgor and dehydration of the cytoplasm. To counteract the outflow of water, microorganisms increase their intracellular solute pool by amassing large amounts of organic osmolytes, the so-called compatible solutes. These osmoprotectants are highly congruous with the physiology of the cell and comprise a limited number of substances including the disaccharide trehalose, the amino acid proline, and the trimethylammonium compound glycine betaine. The intracellular amassing of compatible solutes as an adaptive strategy to high-osmolality environments is evolutionarily well-conserved in Bacteria, Archaea, and Eukarya. Furthermore, the nature of the osmolytes that are accumulated during water stress is maintained across the kingdoms, reflecting fundamental constraints on the kind of solutes that are compatible with macromolecular and cellular functions. Generally, compatible solutes can be amassed by microorganisms through uptake and synthesis. Here we summarise the molecular mechanisms of compatible solute accumulation in Escherichia coli and Bacillus subtilis, model organisms for the gram-negative and gram-positive branches of bacteria.


Asunto(s)
Fenómenos Fisiológicos Bacterianos , Transportadoras de Casetes de Unión a ATP/metabolismo , Bacillus subtilis/metabolismo , Betaína/metabolismo , Cationes/farmacocinética , Escherichia coli/metabolismo , Genes Reguladores/fisiología , Glutamatos/farmacocinética , Ácido Glutámico/biosíntesis , Concentración Osmolar , Trehalosa/biosíntesis , Equilibrio Hidroelectrolítico/fisiología
14.
J Oral Rehabil ; 22(9): 691-8, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7490669

RESUMEN

Primary splinting of fixtures with bar attachments has proved to be clinically effective for overdentures on osseointegrated implants in the edentulous mandible. However, in vitro investigations indicate that a more favourable force transfer to the individual fixtures can be attained by secondary splinting of four implants with conical double crowns. This observation could be confirmed in the present study by measurement of implant deflection in a model of the mandible by means of interferometric optical holography. Telescope crowns with conical interface brought about functionally more even movement characteristics of the implants compared to rigid or jointed bar attachments. Moreover, the conical double crowns always ensured a stable position of the denture in contrast to jointed attachments. These results underscore the need to test conical double crowns clinically as anchors for overdentures on osseointegrated implants.


Asunto(s)
Implantación Dental Endoósea , Implantes Dentales , Ajuste de Precisión de Prótesis , Prótesis de Recubrimiento , Oseointegración , Coronas , Pilares Dentales , Diseño de Prótesis Dental , Holografía , Humanos , Interferometría , Arcada Edéntula , Mandíbula , Modelos Anatómicos , Estrés Mecánico , Propiedades de Superficie , Titanio
15.
J Bacteriol ; 176(17): 5364-71, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8071213

RESUMEN

Exogenously provided glycine betaine functions as an efficient osmoprotectant for Bacillus subtilis in high-osmolarity environments. This gram-positive soil organism is not able to increase the intracellular level of glycine betaine through de novo synthesis in defined medium (A. M. Whatmore, J. A. Chudek, and R. H. Reed, J. Gen. Microbiol. 136:2527-2535, 1990). We found, however, that B. subtilis can synthesize glycine betaine when its biosynthetic precursor, choline, is present in the growth medium. Uptake studies with radiolabelled [methyl-14C]choline demonstrated that choline transport is osmotically controlled and is mediated by a high-affinity uptake system. Choline transport of cells grown in low- and high-osmolarity media showed Michaelis-Menten kinetics with Km values of 3 and 5 microM and maximum rates of transport (Vmax) of 10 and 36 nmol min-1 mg of protein-1, respectively. The choline transporter exhibited considerable substrate specificity, and the results of competition experiments suggest that the fully methylated quaternary ammonium group is a key feature for substrate recognition. Thin-layer chromatography revealed that the radioactivity from exogenously provided [methyl-14C]choline accumulated intracellularly as [methyl-14C]glycine betaine, demonstrating that B. subtilis possesses enzymes for the oxidative conversion of choline into glycine betaine. Exogenously provided choline significantly increased the growth rate of B. subtilis in high-osmolarity media and permitted its proliferation under conditions that are otherwise strongly inhibitory for its growth. Choline and glycine betaine were not used as sole sources of carbon or nitrogen, consistent with their functional role in the process of adaptation of B. subtilis to high-osmolarity stress.


Asunto(s)
Bacillus subtilis/fisiología , Betaína/metabolismo , Colina/metabolismo , Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/metabolismo , Transporte Biológico , Clonación Molecular , Medios de Cultivo , Escherichia coli , Cinética , Concentración Osmolar , Cloruro de Sodio/farmacología , Factores de Tiempo
16.
J Bacteriol ; 179(20): 6213-20, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9335265

RESUMEN

The OpuA transport system of Bacillus subtilis functions as a high-affinity uptake system for the osmoprotectant glycine betaine. It is a member of the ABC transporter superfamily and consists of an ATPase (OpuAA), an integral membrane protein (OpuAB), and a hydrophilic polypeptide (OpuAC) that shows the signature sequence of lipoproteins (B. Kempf and E. Bremer, J. Biol. Chem. 270:16701-16713, 1995). The OpuAC protein might thus serve as an extracellular substrate binding protein anchored in the cytoplasmic membrane via a lipid modification at an amino-terminal cysteine residue. A malE-opuAC hybrid gene was constructed and used to purify a lipidless OpuAC protein. The purified protein bound radiolabeled glycine betaine avidly and exhibited a KD of 6 microM for this ligand, demonstrating that OpuAC indeed functions as the substrate binding protein for the B. subtilis OpuA system. We have selectively expressed the opuAC gene under T7 phi10 control in Escherichia coli and have demonstrated through its metabolic labeling with [3H]palmitic acid that OpuAC is a lipoprotein. A mutant expressing an OpuAC protein in which the amino-terminal cysteine residue was changed to an alanine (OpuAC-3) was constructed by oligonucleotide site-directed mutagenesis. The OpuAC-3 protein was not acylated by [3H]palmitic acid, and part of it was secreted into the periplasmic space of E. coli, where it could be released from the cells by cold osmotic shock. The opuAC-3 mutation was recombined into an otherwise wild-type opuA operon in the chromosome of B. subtilis. Unexpectedly, this mutant OpuAC system still functioned efficiently for glycine betaine acquisition in vivo under high-osmolarity growth conditions. In addition, the mutant OpuA transporter exhibited kinetic parameters similar to that of the wild-type system. Our data suggest that the lipidless OpuAC-3 protein is held in the cytoplasmic membrane of B. subtilis via its uncleaved hydrophobic signal peptide.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Bacillus subtilis/metabolismo , Proteínas Bacterianas/metabolismo , Betaína/metabolismo , Proteínas Portadoras/metabolismo , Proteínas de Escherichia coli , Lipoproteínas/metabolismo , Proteínas de Transporte de Membrana , Proteínas de Unión Periplasmáticas , Bacillus subtilis/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/aislamiento & purificación , Transporte Biológico , Proteínas Portadoras/genética , Proteínas Portadoras/aislamiento & purificación , Cromosomas Bacterianos , Escherichia coli/genética , Cinética , Lipoproteínas/genética , Lipoproteínas/aislamiento & purificación , Mutagénesis Sitio-Dirigida , Ácido Palmítico/metabolismo
17.
Z Gesamte Inn Med ; 44(21): 649-52, 1989 Nov 01.
Artículo en Alemán | MEDLINE | ID: mdl-2609700

RESUMEN

The individual valuation of risks in patients with acute myocardial infarction on the basis of a monitoring of the creatine kinase (CK) is made evident as relevant to practice for the basic medical care. Thereby a classification of risk groups on the basis of CKmax (less than or equal to 23; greater than 23 less than or equal to 40; greater than 40 less than or equal to 60; greater than 60 mumol/l.s) is controlled. The measurement of the ejection fraction global was performed also according to risk groups (greater than 60; greater than 45 less than or equal to 60; greater than 30 less than or equal to 45; less than or equal to 30%). Parallel to this a classification of the patients according to the electrocardiogram (non-Q-wave, Q-wave) was retrospectively performed. The anamnestic information Re-AMI was individually taken into consideration for the evaluation of CKmax. In 2.5% of the patients in comparison to the ejection fraction the risk group classification of CKmax was globally carried out into a higher group without an an principal incorrect evaluation of the risk (slight, middle, high) in the first AMI. No patient with middle or high risk in the first AMI was incorrectly grouped according to the risk group CKmax or ejection fraction global.


Asunto(s)
Gasto Cardíaco/fisiología , Creatina Quinasa/sangre , Infarto del Miocardio/diagnóstico , Electrocardiografía , Humanos , Persona de Mediana Edad , Infarto del Miocardio/enzimología , Pronóstico , Factores de Riesgo
18.
Cell Growth Differ ; 10(12): 813-8, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10616906

RESUMEN

The PAX3-FKHR fusion protein of human alveolar rhabdomyosarcoma consists of the DNA-binding domains of PAX3 and the transcriptional activation domain of FKHR. It induces oncogenic transformation in cultures of chicken embryo fibroblasts (CEFs). PAX3-FKHR-transformed CEFs have been kept in continuous culture for more than 1 year; when quiescent, portions of the cultures differentiate into several distinct cell types. Deletion analysis suggests that both DNA binding and transcriptional activation are required for the induction of the PAX3-FKHR-transformed cellular phenotype. Mutant PAX3-FKHR proteins with reduced DNA binding or transactivation induce altered cellular morphologies and growth behavior distinct from that of CEFs expressing wild-type PAX3-FKHR. Mutant proteins that completely lack DNA binding or transactivation potential fail to transform.


Asunto(s)
Transformación Celular Neoplásica , Proteínas de Unión al ADN/metabolismo , Proteínas Oncogénicas/metabolismo , Rabdomiosarcoma Alveolar/genética , Factores de Transcripción/metabolismo , Animales , Embrión de Pollo , ADN/metabolismo , Proteínas de Unión al ADN/genética , Fibroblastos/citología , Proteína Forkhead Box O1 , Factores de Transcripción Forkhead , Humanos , Mutagénesis , Proteínas Oncogénicas/genética , Factor de Transcripción PAX3 , Factores de Transcripción Paired Box , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Eliminación de Secuencia , Factores de Transcripción/genética , Activación Transcripcional
19.
Mol Gen Genet ; 246(6): 783-6, 1995 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-7898450

RESUMEN

The ProP and ProU transport systems of Escherichia coli mediate the uptake of several osmoprotectants including glycine betaine. Here we report that both ProP and ProU are involved in the transport of the potent osmoprotectant proline betaine. A set of isogenic E. coli strains carrying deletions in either the proP or proU loci was constructed. The growth properties of these mutants in high osmolarity minimal media containing 1 mM proline betaine demonstrated that the osmoprotective effect of this compound was dependent on either an intact ProP or ProU uptake system. Proline betaine competes with glycine betaine for binding to the proU-encoded periplasmic substrate binding protein (ProX) and we estimate a KD of 5.2 microM for proline betaine binding. This value is similar to the binding constant of the ProX protein determined previously for the binding of glycine betaine (KD of 1.4 microM). Our results thus demonstrate that the binding-protein-dependent ProU transport system of E. coli mediates the efficient uptake of the osmoprotectants glycine betaine and proline betaine.


Asunto(s)
Sistemas de Transporte de Aminoácidos , Proteínas Bacterianas/metabolismo , Proteínas Portadoras/metabolismo , Proteínas de Escherichia coli , Escherichia coli/metabolismo , Prolina/análogos & derivados , Simportadores , Proteínas Bacterianas/genética , Betaína/metabolismo , Transporte Biológico , Proteínas Portadoras/genética , Eliminación de Gen , Presión Osmótica , Prolina/metabolismo , Unión Proteica
20.
J Biol Chem ; 269(9): 6578-8, 1994 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-8120010

RESUMEN

The Escherichia coli hns gene encodes the abundant nucleoid-associated DNA-binding protein H-NS. Mutations in hns alter the expression of many genes with unrelated functions and result in a derepression of the proU operon (proVWX) without abolishing the osmotic control of its transcription. We have investigated the interactions of H-NS with the proU regulatory region by deletion analysis of cis-acting sequences, competitive gel retardation assays, and DNase I footprinting. The negative effect of H-NS on proU transcription was mediated by cis-acting sequences within proV but did not depend on the presence of a curved DNA segment upstream of the proU-35 region previously characterized as a target for H-NS binding in vitro. We detected a 46-base pair high affinity H-NS binding region downstream of the proU promoter at the 5' end of the proV gene and a complex array of additional H-NS binding sites which suggest the presence of an extended H-NS nucleoprotein complex. Most of the H-NS binding sites were highly A+T-rich and carried stretches of 5 or more consecutive A-T base pairs. The implications of our results for the osmotic regulation of proU transcription are discussed.


Asunto(s)
Sistemas de Transporte de Aminoácidos , Proteínas de la Membrana Bacteriana Externa/metabolismo , Proteínas Bacterianas/biosíntesis , Proteínas Portadoras/biosíntesis , ADN Bacteriano/metabolismo , Proteínas de Unión al ADN/metabolismo , Escherichia coli/metabolismo , Regulación Bacteriana de la Expresión Génica , Operón , Regiones Promotoras Genéticas , Secuencias Reguladoras de Ácidos Nucleicos , Proteínas de la Membrana Bacteriana Externa/biosíntesis , Proteínas de la Membrana Bacteriana Externa/aislamiento & purificación , Secuencia de Bases , Sitios de Unión , ADN Bacteriano/aislamiento & purificación , Proteínas de Unión al ADN/biosíntesis , Proteínas de Unión al ADN/aislamiento & purificación , Escherichia coli/genética , Expresión Génica , Genes Bacterianos , Cinética , Datos de Secuencia Molecular , Mutagénesis Insercional , Plásmidos , Mapeo Restrictivo
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