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2.
Clin Neuropathol ; 27(6): 369-72, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19130732

RESUMEN

Here we report a rare case of cerebellar ganglioglioma accompanied by a large cyst, and present a review of the reported 28 cases with cerebellar ganglioglioma. An otherwise healthy 46-year-old woman complained of gradual headache and truncal ataxia. MRI revealed a huge cystic lesion with a mural nodule in the left cerebellar hemisphere. The tumor was resected totally. Histologically, it was composed of neuronal and glial elements, and was accordingly diagnosed as ganglioglioma.


Asunto(s)
Neoplasias Cerebelosas/patología , Quistes/patología , Ganglioglioma/patología , Neoplasias Cerebelosas/cirugía , Quistes/cirugía , Femenino , Ganglioglioma/cirugía , Humanos , Persona de Mediana Edad
3.
Bone Joint J ; 100-B(8): 1018-1024, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30062951

RESUMEN

Aims: The purpose of this study was to compare two different types of metal-on-metal (MoM) bearing for total hip arthroplasty (THA): one with a large femoral head (38 mm to 52 mm) and the other with a conventional femoral head (28 mm or 32 mm). We compared clinical outcome, blood metal ion levels, and the incidence of pseudotumour in the two groups. Patients and Methods: Between December 2009 and December 2011, 62 patients underwent MoM THA with a large femoral head (Magnum group) and 57 patients an MoM THA with a conventional femoral head (conventional group). Clinical outcome was assessed using the Harris Hip score, University of California, Los Angeles (UCLA) activity score and EuroQol-5D (EQ-5D). Blood metal ion levels were measured and MRI scans were analyzed at a minimum of five years postoperatively. Results: No acetabular component was implanted with more than 50° of inclination in either group. The Harris Hip Score, UCLA activity score, and EQ-5D improved postoperatively in both groups; no significant clinical differences were noted between the groups. The blood cobalt ion levels in the conventional group continued to rise postoperatively to five years while reaching a plateau at two years postoperatively in the Magnum group. At five years, the mean cobalt ion level of 1.16 µg/l (sd 1.32) in the Magnum group was significantly lower than the 3.77 µg/l (sd 9.80) seen in the conventional group (p = 0.0015). The incidence of moderate to severe pseudotumour was 4.7% in the Magnum group and 20.6% in the conventional group. There were no dislocations in the Magnum group and two in the conventional group. One patient in the Magnum group underwent revision for pseudotumour at 4.7 years postoperatively. Conclusion: At five years, a well-positioned large head MoM THA has a significantly lower level of metal ion release and a lower incidence of moderate to severe pseudotumour than a MoM bearing of conventional size. Cite this article: Bone Joint J 2018;100-B:1018-24.


Asunto(s)
Artroplastia de Reemplazo de Cadera/instrumentación , Granuloma de Células Plasmáticas/etiología , Prótesis de Cadera , Prótesis Articulares de Metal sobre Metal , Anciano , Artroplastia de Reemplazo de Cadera/efectos adversos , Femenino , Humanos , Iones/metabolismo , Estimación de Kaplan-Meier , Masculino , Metales/metabolismo , Tempo Operativo , Medición de Resultados Informados por el Paciente , Complicaciones Posoperatorias/etiología , Diseño de Prótesis , Resultado del Tratamiento
4.
J Clin Invest ; 99(10): 2351-7, 1997 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-9153276

RESUMEN

Homeostasis of body fluid is maintained by the kidneys, which contain two million glomeruli for blood filtration. A glomerulus is formed by growth of Bowman's capsule harmonized with a capillary during kidney development. The vascular endothelial growth factor (VEGF) is an essential angiogenic cytokine, and VEGF deficiency is known to be fatal in mice in early embryonic stages. As secretions of VEGF from cultured kidneys vary according to developmental stages, the role of VEGF in kidney development was studied in vivo by blocking the endogenous VEGF activity with antibody in newborn mice, in which most organs are already developed but kidneys are still developing. The antibody-treated animals showed normal growth but systemic edema. Vessel formation in the superficial renal cortex was disturbed, nephrogenic areas were diminished, and the number of developing nephrons decreased significantly. Many abnormal glomeruli, lacking capillary tufts, were observed in the antibody-treated mice, and VEGF expression in their Bowman's capsule showed a compensatory increase. These results suggest that VEGF mediates communication between the Bowman's capsule and capillary endothelial cells for developing a glomerulus as well as promoting nephrogenesis. In conclusion, VEGF is likely to be an essential molecule for kidney development, and especially for glomerulogenesis.


Asunto(s)
Desarrollo Embrionario y Fetal , Factores de Crecimiento Endotelial/biosíntesis , Glomérulos Renales/embriología , Riñón/embriología , Linfocinas/biosíntesis , Nefronas/embriología , Animales , Animales Recién Nacidos , Anticuerpos , Membrana Basal/fisiología , Membrana Basal/ultraestructura , Capilares/embriología , Capilares/fisiología , Embrión de Mamíferos , Factores de Crecimiento Endotelial/metabolismo , Factores de Crecimiento Endotelial/fisiología , Inmunohistoquímica , Riñón/irrigación sanguínea , Riñón/metabolismo , Corteza Renal/irrigación sanguínea , Corteza Renal/embriología , Glomérulos Renales/ultraestructura , Linfocinas/metabolismo , Linfocinas/fisiología , Ratones , Microscopía Electrónica , Técnicas de Cultivo de Órganos , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
5.
Food Chem Toxicol ; 44(4): 455-61, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16198037

RESUMEN

To evaluate the main intake source of arsenic by the villagers from arsenic-affected families in Jalangi and Domkol blocks in Mushidabad district, West Bengal-India, we determined the concentrations of arsenic in tube-well water and in food composites, mainly including vegetables and cereals collected from the surveyed families which were cultivated in that region. The daily dietary intakes of arsenic by the villagers were estimated and the excretions of arsenic through urine and hair were determined. The arsenic concentrations in hair and urine of the studied population living in mild (2.78 microg/L), moderate (30.7 microg/L) and high (118 microg/L) arsenic-affected families were 133, 1,391 and 4,713 microg/kg and 43.1, 244 and 336 microg/L, respectively. The linear regressions show good correlations between arsenic concentrations in water vs hair (r(2)=0.928, p<0.001) and water vs urine (r(2)=0.464, p<0.01). Approximately 29.4%, 58.1% and 62.1% of adult population from mild, moderate and high arsenic-affected families were suffering from arsenical skin manifestations. The mean arsenic concentrations of food composites (vegetables and cereals) in high arsenic-affected families are not significantly different from mild arsenic-affected families. The daily dietary intakes of arsenic from water and food composites of the studied population, living in high, moderate and mild arsenic-affected families were 568, 228 and 137 microg, respectively. The linear regressions show good correlations between arsenic concentrations in hair vs daily dietary intake (r(2)=0.452, p<0.001) and urine vs daily dietary intake (r(2)=0.134, p<0.001). The water for drinking contributed 6.07%, 26.7% and 58.1% of total arsenic in our study from mild, moderate and high arsenic-affected families. The result suggested that the contaminated water from high arsenic-affected families should be the main source for intake of arsenic. On contrary, the contribution of arsenic-contaminated food composites from mild and moderate arsenic-affected families might be the main source for intake of arsenic. The Food and Agriculture Organization/World Health Organization (FAO/WHO) provisional tolerable weekly intake (PTWI) values of arsenic in our study were 3.32, 5.75 and 12.9 microg/kg body weight/day from mild, moderate and high arsenic-affected families, respectively, which is higher than the recommended PTWI value of arsenic (2.1 microg/kg body weight/day).


Asunto(s)
Arsénico/toxicidad , Contaminación de Alimentos/estadística & datos numéricos , Cabello/química , Contaminantes Químicos del Agua/toxicidad , Adulto , Arsénico/orina , Niño , Exposición a Riesgos Ambientales , Monitoreo del Ambiente , Monitoreo Epidemiológico , Femenino , Análisis de los Alimentos , Humanos , India/epidemiología , Masculino , Contaminantes Químicos del Agua/orina , Abastecimiento de Agua
6.
Cancer Res ; 60(11): 2840-4, 2000 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-10850425

RESUMEN

Bone morphogenetic proteins (BMPs) are potential regulators of prostate cancer cell growth and metastasis that signal through an interaction with BMP membrane receptors (BMPRs) type I and type II. In the present study, Western blot and immunohistochemical analysis of BMPRs were carried out in benign and malignant human prostate tissues to explain the loss of BMP response in human prostate cancer cells. The results demonstrated that the benign prostate specimens expressed high levels of all three BMPRs. In normal prostate, BMPRs were localized predominantly to epithelial cells. Among prostate cancer specimens, well-differentiated cancers were positive for the expression of BMPR-II, BMPR-IA, and BMPR-IB, for the most part. In contrast, only 1 of 10 poorly differentiated prostate cancer cases was positive for each of the three BMPRs (P < 0.005 for all three receptors). Taken together, these results indicate that human prostate cancer cells frequently exhibit loss of expression of BMPRs and suggest that loss of BMPRs may play an important role during the progression of prostate cancer.


Asunto(s)
Neoplasias de la Próstata/metabolismo , Proteínas Serina-Treonina Quinasas/biosíntesis , Receptores de Factores de Crecimiento/biosíntesis , Western Blotting , Receptores de Proteínas Morfogenéticas Óseas de Tipo 1 , Receptores de Proteínas Morfogenéticas Óseas de Tipo II , Progresión de la Enfermedad , Células Epiteliales/metabolismo , Humanos , Inmunohistoquímica , Masculino , Próstata/metabolismo , Neoplasias de la Próstata/patología , Factores de Crecimiento Transformadores/metabolismo
7.
Oncogene ; 18(5): 1197-203, 1999 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-10022125

RESUMEN

Recent studies have shown that patients whose bladder cancer exhibit overexpression of RB protein as measured by immunohistochemical analysis do equally poorly as those with loss of RB function. We hypothesized that loss of p16 protein function could be related to RB overexpression, since p16 can induce transcriptional downregulation of RB and its loss may lead to aberrant RB regulation. Conversely, loss of RB function has been associated with high p16 protein expression in several other tumor types. In the present study RB negative bladder tumors also exhibited strong nuclear p16 staining while each tumor with strong, homogeneous RB nuclear staining were p16 negative, supporting our hypothesis. To expand on these immunohistochemical studies additional cases were selected in which the status of the p16 encoding gene had been determined at the molecular level. Absent p16 and high RB protein expression was found in the tumors having loss of heterozygosity within 9p21 and a structural change (mutation or deletion) of the remaining p16 encoding gene allele, confirming the staining results. These results strongly support the hypothesis that the RB nuclear overexpression recently associated with poor prognosis in bladder cancer is also associated with loss of p16 function and implies that loss of p16 function could be equally deleterious as RB loss in bladder and likely other cancers.


Asunto(s)
Inhibidor p16 de la Quinasa Dependiente de Ciclina/aislamiento & purificación , Proteína de Retinoblastoma/aislamiento & purificación , Neoplasias de la Vejiga Urinaria/química , Biopsia , Cromosomas Humanos Par 9/genética , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Cistectomía , Humanos , Inmunohistoquímica , Pérdida de Heterocigocidad , Repeticiones de Microsatélite , Modelos Biológicos , Mutación , Pronóstico , Eliminación de Secuencia , Neoplasias de la Vejiga Urinaria/patología
8.
Biochim Biophys Acta ; 1105(1): 125-30, 1992 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-1567891

RESUMEN

The water-soluble alpha-toxin monomers of Staphylococcus aureus become hexamers forming the transmembrane pore when exposed to the membranes. This pore is freely permeable to small hydrophilic molecules, e.g. carboxyfluorescein, and becomes less permeable in the presence of calcium ions. Calcium ion-mediated decrease of the carboxyfluorescein leakage could not be eliminated by EDTA added in the medium, but the carboxyfluorescein could be freed by EDTA added in the intraliposomal space. This result suggests that the alpha-toxin pore changes its conformation as the calcium ion is bound and that the binding site is exposed to the intraliposomal side of the membrane. The interaction between the alpha-toxin hexamer and 8-anilino-1-naphthalene-sulfonic acid (ANS) was monitored by determining the fluorescence in the presence and absence of calcium chloride. The mean distances between the tryptophan residues of the alpha-toxin hexamer and the bound ANS were calculated to be 1.90 and 1.80 nm in the absence and presence, respectively, of calcium ions. The results showed the calcium ion mediated conformational change of the membrane-embedded alpha-toxin hexamer.


Asunto(s)
Toxinas Bacterianas/farmacología , Calcio/metabolismo , Proteínas Hemolisinas/metabolismo , Membranas/efectos de los fármacos , Staphylococcus aureus/metabolismo , Naftalenosulfonatos de Anilina/química , Toxinas Bacterianas/metabolismo , Cationes Bivalentes , Fluoresceínas/metabolismo , Colorantes Fluorescentes , Liposomas , Membranas/metabolismo , Permeabilidad , Conformación Proteica , Espectrometría de Fluorescencia
9.
Biochim Biophys Acta ; 769(2): 348-56, 1984 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-6320874

RESUMEN

Purified porin OmpF from Escherichia coli outer membrane was chemically modified by acetylation and succinylation of amino groups and by amidation of the carboxyl groups. Native and chemically modified porins were incorporated into lipid bilayer membranes and the permeability properties of the pores were studied. Acetylation and succinylation of the porin trimers had almost no influence on the single channel conductance in the presence of small cations and anions and the cation selectivity remained essentially unchanged as compared with the native porin. Amidation had also only little influence on the single channel conductance and changed the pore conductance at maximum by less than 50%, whereas the cation selectivity of the porin is completely lost after amidation. The results suggest that the structure of the porin pore remains essentially unchanged after chemical modification of the pores and that their cation selectivity is caused by an excess of negatively charged groups inside the pore and/or on the surface of the protein. Furthermore, it seems very unlikely that the pore contains any positively charged group at neutral pH.


Asunto(s)
Escherichia coli/análisis , Membrana Dobles de Lípidos/metabolismo , Proteínas de la Membrana/metabolismo , Acetilación , Amidas/metabolismo , Concentración de Iones de Hidrógeno , Porinas , Succinatos/metabolismo , Ácido Succínico
10.
Biochim Biophys Acta ; 1387(1-2): 65-79, 1998 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-9748507

RESUMEN

Using part of the dnaK gene from Bacillus subtilis as a probe, a 4. 4-kbp SacI-BglII fragment of chromosomal DNA of Bacillus brevis, a protein-hypersecreting bacterium, was cloned. Nucleotide sequencing revealed 3 open reading frames in the order of grpE-dnaK-dnaJ homologues. We purified DnaK protein to homogeneity from B. brevis HPD31 harboring a multi-copy dnaK expression plasmid. Purified DnaK showed ATPase activity which was synergistically stimulated 14-fold by the addition of glutathione S-transferase-DnaJ and glutathione S-transferase-GrpE fusion proteins. DnaK hydrolyzed not only ATP but also CTP, UTP, and GTP at about 40% of the efficiency of ATP. The specific activity of DnaK-ATPase was 7.25x10-3 unit/mg protein (the turnover number against ATP was 0.47 min-1) under our assay conditions. The DnaK dimers dissociated into monomers on addition of ATP, GTP, CTP, UTP and ATPgammaS, but not ADP or AMP. DnaK formed a stable complex with permanently unfolded carboxymethylated alpha-lactalbumin but not with native alpha-lactalbumin, and this complex was dissociated by addition of ATP/Mg. Formation of this complex was inhibited in the presence of inorganic phosphate.


Asunto(s)
Adenosina Trifosfatasas/química , Bacillus/enzimología , Proteínas de Escherichia coli , Proteínas HSP70 de Choque Térmico/química , Chaperonas Moleculares/química , Adenosina Trifosfatasas/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas , Secuencia de Bases , Clonación Molecular , Endopeptidasas/metabolismo , Activación Enzimática/fisiología , Glutatión Transferasa/genética , Proteínas del Choque Térmico HSP40 , Proteínas de Choque Térmico/farmacología , Lactalbúmina/metabolismo , Datos de Secuencia Molecular , Nucleótidos/farmacología , Fosfatos/farmacología , Conformación Proteica , Pliegue de Proteína , Proteínas Recombinantes de Fusión/farmacología , Análisis de Secuencia de ADN , Especificidad por Sustrato
11.
Clin Cancer Res ; 5(9): 2520-5, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10499628

RESUMEN

Transforming growth factor (TGF) beta, a potent growth inhibitor of proliferation in most cells, usually exerts its effects through an interaction with membrane receptors, type I (TbetaR-I) and type II (TbetaR-II). In the present study, the expression of TGF-beta receptors was correlated with tumor grade, pathological stage, and probability of progression and survival in patients with bladder transitional cell carcinoma (TCC). To this end, immunohistochemistry was carried out in specimens obtained from 59 patients who underwent either radical cystectomy or transurethral resection of bladder tumor. Among these patients, 18 (30.5 %) had loss of TbetaR-I expression, whereas 27 (44.0%) had loss of TbetaR-II expression. There was a correlation between the loss of expression of TbetaR-I and TbetaR-II and the tumor grade (P = 0.041 and P = 0.026, respectively). In addition, both pathological and lymph node status also were associated with the loss of TbetaR-I and TbetaR-II expression (P = 0.025 and P = 0.004, respectively). Interestingly though, only the loss of expression of TbetaR-I was associated with an increased probability of tumor progression and a decreased probability of survival (P = 0.0046 and P = 0.0022, respectively). These results suggest that the status of TbetaR-I expression may be a potential prognostic marker in patients with bladder TCC.


Asunto(s)
Receptores de Activinas Tipo I , Carcinoma de Células Transicionales/metabolismo , Proteínas Serina-Treonina Quinasas/biosíntesis , Receptores de Factores de Crecimiento Transformadores beta/biosíntesis , Neoplasias de la Vejiga Urinaria/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Transicionales/patología , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Receptor Tipo I de Factor de Crecimiento Transformador beta , Receptor Tipo II de Factor de Crecimiento Transformador beta , Factores de Riesgo , Análisis de Supervivencia , Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/patología
12.
Endocrinology ; 142(1): 407-13, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11145604

RESUMEN

Secondary hyperparathyroidism, one of the most frequently encountered disorders of the calcium homeostasis, is characterized by an increase in parathyroid epithelial (PT) cell number, which is crucial from a functional viewpoint. However, it is still unknown what factors are involved in PT cell proliferation. Endothelin-1 (ET-1), a vasoconstrictive peptide, has been shown to act as a mitogen in a variety of cell types. Rat PT cells are reported to synthesize ET-1 and possess its receptors. To test the hypothesis that ET-1 plays a role in PT cell proliferation, we used rat test subjects fed a low calcium diet for 8 weeks (low Ca rats). The number of the proliferating PT cells, measured by proliferating cell nuclear antigen immunostaining, was significantly increased, with striking immunoreactivity of ET-1 in the low Ca rats. An endothelin receptor antagonist, bosentan (100 mg/kg.day), prevented any increase in the proliferation of PT cells in the low Ca rats (14.3 +/- 2.7/1000 PT cells with no bosentan; 2.1 +/- 1.3 with bosentan; P < 0.01). These results indicate that ET-1 is involved in PT cell proliferation in vivo and suggest that blocking of ET receptors may become one of the important therapeutic strategies for preventing secondary hyperparathyroidism.


Asunto(s)
Calcio/deficiencia , Antagonistas de los Receptores de Endotelina , Hiperparatiroidismo/fisiopatología , Glándulas Paratiroides/patología , Sulfonamidas/farmacología , Animales , Bosentán , Calcio de la Dieta , División Celular/efectos de los fármacos , Endotelina-1/fisiología , Hiperparatiroidismo/etiología , Hiperparatiroidismo/patología , Masculino , Glándulas Paratiroides/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
13.
J Clin Endocrinol Metab ; 83(6): 2210-3, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9626162

RESUMEN

Liddle's syndrome is an autosomal dominant form of salt sensitive hypertension caused by mutations in the beta or gamma subunit of the epithelial sodium channel. Systematic mutagenesis studies revealed that a conserved PPPXY sequence (PY motif) of the C-terminus of the alpha, beta, or gamma subunits might be involved in the regulation of the channel activity. However, only two missense mutations in the PY motif of the beta subunit have been reported to cause Liddle's syndrome. We sequenced the C-termini of the beta and gamma subunits of the epithelial sodium channel in a Japanese family clinically diagnosed as having Liddle's syndrome and found a new missense mutation in the PY motif of the beta subunit, P615S. Expression studies with P615S mutant in Xenopus oocytes resulted in an about 3-fold increase in the amiloride-sensitive sodium current compared to the wild type (p = 0.001). These findings provide further clinical evidence for the hypothesis that a conserved PY motif may be critically important for the regulation of the epithelial sodium channel.


Asunto(s)
Hipertensión/genética , Mutación Puntual , Canales de Sodio/genética , Adulto , Alelos , Secuencia de Bases , Codón , ADN/química , Epitelio/química , Femenino , Humanos , Masculino , Mutagénesis , Linaje , Reacción en Cadena de la Polimerasa , Prolina/genética , Análisis de Secuencia de ADN , Serina/genética , Canales de Sodio/química , Síndrome
14.
FEBS Lett ; 493(2-3): 134-8, 2001 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-11287010

RESUMEN

Enzymes from extremely halophilic archaea are readily denatured in the absence of a high salt concentration. However, we have observed here that a nucleoside diphosphate kinase prepared from Halobacterium salinarum was active and stable in the absence of salt, though it has the amino acid composition characteristic of halophilic enzymes. Recombinant nucleoside diphosphate kinase expressed in Escherichia coli requires salt for activation in vitro, but once it acquires the proper folding, it no longer requires the presence of salts for its activity and stability.


Asunto(s)
Halobacterium salinarum/enzimología , Nucleósido-Difosfato Quinasa/química , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Cartilla de ADN/genética , Activación Enzimática/efectos de los fármacos , Estabilidad de Enzimas , Escherichia coli/genética , Expresión Génica , Genes Arqueales , Halobacterium salinarum/genética , Datos de Secuencia Molecular , Nucleósido-Difosfato Quinasa/genética , Nucleósido-Difosfato Quinasa/metabolismo , Conformación Proteica/efectos de los fármacos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Cloruro de Sodio/farmacología
15.
Int J Radiat Oncol Biol Phys ; 51(1): 16-22, 2001 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-11516846

RESUMEN

PURPOSE: To determine the relationship of p53, retinoblastoma (RB), and p16 expression between precystectomy transurethral resection bladder (TURB) biopsy and matched cystectomy specimens; and to determine the value of p53 immunoreactivity for predicting progression and survival in patients undergoing radical cystectomy. METHODS AND MATERIALS: We performed p53 immunohistochemical staining on matched archival TURB and cystectomy specimens taken from 40 patients. Twenty-seven and 26 of these patients were also evaluated for RB and p16 expression, respectively. RESULTS: Twenty-eight (70%) of the TURB and 22 (55%) of the cystectomy specimens stained positive for p53. RB and p16 protein expression were altered in 19 (70%) and 19 (73%) of the TURB specimens, respectively, and 19 (70%) and 19 (73%) of the cystectomy specimens, respectively. There was a strong correlation between p53, RB, and p16 expression and TURB and cystectomy specimens (all p < 0.001). In preoperative and postoperative multivariate analyses, biopsy p53 and cystectomy p53 were independently associated with disease progression (p = 0.049 and p = 0.034, respectively) and bladder cancer-related death (p = 0.044 and p = 0.037, respectively). CONCLUSION: p53, RB, and p16 expression patterns on TURB specimens correlate with cystectomy specimens. p53 immunoreactivity is an independent predictor of disease progression and bladder cancer survival. These data support the potential of prognostic staging using immunohistochemical analysis on bladder biopsy specimens prior to neoadjuvant or definitive therapy.


Asunto(s)
Carcinoma de Células Transicionales/química , Inhibidor p16 de la Quinasa Dependiente de Ciclina/análisis , Proteínas de Neoplasias/análisis , Proteína de Retinoblastoma/análisis , Proteína p53 Supresora de Tumor/análisis , Neoplasias de la Vejiga Urinaria/química , Vejiga Urinaria/química , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Biopsia , Carcinoma de Células Transicionales/mortalidad , Carcinoma de Células Transicionales/patología , Cistectomía , Progresión de la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Compuestos Organotiofosforados , Pronóstico , Modelos de Riesgos Proporcionales , Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/mortalidad , Neoplasias de la Vejiga Urinaria/patología
16.
Am J Hypertens ; 6(1): 15-20, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8427657

RESUMEN

To investigate a possible involvement of endogenous erythropoietin (EPO) in the salt sensitivity of blood pressure in essential hypertensive (EHT) patients, plasma EPO concentrations were measured during different salt intakes in 14 patients with EHT. All patients were given low salt (34 mmol NaCl/day) and high salt (342 mmol NaCl/day) diet of 7 days each. The plasma EPO concentrations were significantly higher on the high salt diet than those of low salt diet (23.5 +/- 1.9 v 18.7 +/- 1.8 mIU/ml, mean +/- SD, P < .05). The percentage change of plasma EPO concentration with salt loading correlated positively with hematocrit (Ht) at high salt diet (r = -0.62, P < .02) and tended to be correlated with plasma hemoglobin at high salt diet (r = 0.52, P < .10). These results suggest that the secretion of EPO is increased in response to hemodilution caused by the salt loading and the increased EPO concentration in plasma which may contribute to the increase in blood pressure through an expansion of total blood volume due to an enhanced red cell generation in combination with salt and water retentions.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Eritropoyetina/sangre , Hipertensión/sangre , Cloruro de Sodio/farmacología , Adulto , Aldosterona/sangre , Factor Natriurético Atrial/sangre , Femenino , Humanos , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Concentración Osmolar , Renina/sangre
17.
J Biochem ; 81(5): 1375-81, 1977 May.
Artículo en Inglés | MEDLINE | ID: mdl-19432

RESUMEN

Bacillus cereus strain K-22 produced two distinct omega-amino acid transaminases, one catalyzing the transamination between beta-alanine and pyruvic acid and the other that between gamma-aminobutyric acid and alpha-ketoglutaric aic. The two enzymes were partially purified and separated from each other by various chromatographies. beta-Alanine:pyruvic acid transaminase and gamma-aminobutyric acid:alpha-ketoglutaric acid transaminase were induced by the addition of beta-alanine and gamma-aminobutyric acid, respectively, to the growth medium. beta-Alanine transaminase showed an optimum pH of 10.0 and optimum temperature of 35 degrees C, and its Km values for beta-alanine and pyruvic acid were both 1.1 mM. gamma-Aminobutyric acid, epsilon-aminocaproic acid, 2-aminoethylphosphonic acid, and propylamine showed about 30-40% of the activity of beta-alanine as amino donors, and oxalacetic acid was as good an amino acceptor as pyruvic acid. The optimum pH and temperature of gamma-aminobutyric acid transaminase were 9.0 and 50 degrees C, respectively, and its Km value for gamma-aminobutyric acid was 2.8 mM, while that for alpha-ketoglutaric acid was 2.3 mM. gamma-Aminobutyric acid and delta-aminovaleric acid were good amino donors but other omega-amino acids were virtually inactive with gamma-aminobutyric acid transaminase; alpha-ketoglutaric acid, and to a lesser extent glyoxylic acid, were active amino acceptors. Sulfhydryl reagents specifically activated gamma-aminobutyric acid transaminase.


Asunto(s)
4-Aminobutirato Transaminasa , Alanina Transaminasa , Bacillus cereus/enzimología , Transaminasas , 4-Aminobutirato Transaminasa/aislamiento & purificación , 4-Aminobutirato Transaminasa/metabolismo , Alanina Transaminasa/aislamiento & purificación , Alanina Transaminasa/metabolismo , Aminoácidos , Concentración de Iones de Hidrógeno , Cinética , Relación Estructura-Actividad , Compuestos de Sulfhidrilo/farmacología , Reactivos de Sulfhidrilo/farmacología , Transaminasas/aislamiento & purificación , Transaminasas/metabolismo
18.
Neuroreport ; 10(16): 3315-9, 1999 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-10599838

RESUMEN

To investigate the neural substrate underlying the mechanisms of Kanji and Kana writing, we conducted a PET activation study during mental writing task in eight right-handed normal Japanese subjects. During scans subjects were required to mentally write a Kanji or three Kana letters with their right hand, for each stimulant word presented auditorily. The direct comparisons between Kanji writing and Kana writing revealed that the left posterior inferior temporal gyrus was activated in Kanji writing while the left angular gyrus was activated in Kana writing. In addition, more extensive areas were activated in Kanji writing compared with Kana writing. These results suggest that different respective neural substrates are involved in Kanji and Kana writing respectively.


Asunto(s)
Encéfalo/fisiología , Circulación Cerebrovascular/fisiología , Escritura Manual , Adolescente , Adulto , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Lateralidad Funcional/fisiología , Humanos , Imaginación/fisiología , Masculino , Valores de Referencia , Tomografía Computarizada de Emisión
19.
Hypertens Res ; 23(1): 39-45, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10737134

RESUMEN

Interest in mitochondrial calcium (Ca2+) uptake and release waned as it became apparent that sarcoplasmic reticulum calcium stores dominate the control of cytoplasmic calcium concentration. Our recent demonstration of a very large rise in vascular smooth muscle (VSM) cytoplasmic sodium (Na+) concentration after inhibition of the sodium, potassium-ATPase (sodium pump) led us to several questions. Do VSM mitochondria show Na(+)-dependent Ca2+ release? Are the documented changes in cytoplasmic Na+ concentration sufficient to cause Ca2+ release? Do features of the cardiac mitochondrial exchange system, including differential sensitivity to a number of calcium antagonists and cation specificity, apply to VSM? We isolated mitochondria from bovine aorta and mesenteric arteries and employed arsenazo III as the Ca2+ indicator. Mitochondria from arterial vessels accumulated added calcium (up to 50 nmol Ca2+/mg protein) and released Ca2+ on exposure to Na+. This concentration-dependent relationship was linear from 0 to 10 mM of Na+, and it plateaued between 20 mM and 40 mM of Na+. VSM mitochondria exposed to 20 mM Na+ released 118 +/- 25 nmol Ca2+ per mg mitochondrial protein in 20 min, when a new equilibrium was reached. Lithium (Li+), in contrast to Na+, produced much smaller amounts of Ca2+ release from the VSM mitochondria. Na+-dependent Ca2+ release was antagonized in a concentration-dependent manner by diltiazem (0-320 microM) with a Ki of 10.2 microM. Nifedipine had a lesser effect, and verapamil produced almost no inhibition. VSM mitochondria responses resemble those from heart mitochondria in that Na+-dependent Ca2+ release is present with a similar range of sensitivity to Na+ and a similar pattern of influence of diltiazem, nifedipine and verapamil. However, the influence of Li+ on Ca2+ release was much smaller and the amount of the Ca2+ released was much greater for VSM mitochondria compared with that reported for heart mitochondria. The large amount of Ca2+ released and the range of Na+ concentration that provoked Ca2+ release being within the physiologically achievable range raise the interesting possibility that these mechanisms may modify intramitochondrial cytosolic Ca2+ concentration, and hence could potentially contribute to the contractile response that follows inhibition of the sodium pump.


Asunto(s)
Canales de Calcio/metabolismo , Calcio/metabolismo , Mitocondrias Musculares/metabolismo , Cloruro de Sodio/farmacología , Animales , Aorta/citología , Aorta/metabolismo , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio/efectos de los fármacos , Bovinos , Diltiazem/farmacología , Arterias Mesentéricas/citología , Arterias Mesentéricas/metabolismo , Mitocondrias Musculares/efectos de los fármacos , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , Nifedipino/farmacología
20.
FEMS Microbiol Lett ; 152(2): 321-6, 1997 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-9231426

RESUMEN

We have purified to apparent homogeneity and characterized a molecular chaperonin GroEL homologue (hpGroEL) from a moderately halophilic eubacterium, Pseudomonas sp. #43. Although this halophilic bacterium requires 1-2 M NaCl for growth, hpGroEL did not require a high concentration of salt for its stability, ATPase activity and refold-promoting activity for denatured protein. The ATPase activity was even more halo-sensitive than that of GroEL from Escherichia coli. The hpGroEL protein promotes Mg(2+)-ATP-dependent refolding of urea-denatured alpha-glucosidase in the presence of E. coli-GroES, indicating that chaperonins 60 and 10 isolated from halophilic and nonhalophilic eubacteria, respectively, can cooperate with each other.


Asunto(s)
Chaperonina 60/aislamiento & purificación , Chaperonina 60/metabolismo , Pseudomonas/química , Adenosina Trifosfatasas/metabolismo , Adenosina Trifosfato/metabolismo , Secuencia de Aminoácidos , Chaperonina 10/metabolismo , Chaperonina 60/química , Escherichia coli/química , Datos de Secuencia Molecular , Peso Molecular , Cloruro de Potasio/farmacología , Pliegue de Proteína , Pseudomonas/efectos de los fármacos , Pseudomonas/crecimiento & desarrollo , Alineación de Secuencia , Cloruro de Sodio/farmacología , alfa-Glucosidasas/química
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