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1.
Int J Sports Med ; 30(12): 892-7, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19885780

RESUMEN

Unlike in Europeans and Africans, the relationship between the human guanine nucleotide binding beta polypeptide 3 (GNB3) C825T gene polymorphism (rs5443) and blood pressures is inconsistent in Asians. The aim of the study was to investigate whether the GNB3 genotype demonstrates different associations with resting blood pressure and body fatness across cardio/respiratory fitness (CRF) levels. A total of 727 Korean women aged 31-60 years (mean, 47.8+/-5.4 years) participated in the study. In subgroup analyses of the obese group, TT individuals had significantly higher values of body weight than CC and CT individuals (p=0.006 and p=0.006, respectively) and body mass index (BMI) (p=0.002 and p=0.011, respectively). TT and CT individuals also tended to have higher CRF values than CC individuals. Regression analyses showed that the association between GNB3 genotype and resting blood pressure remained significant after adjustment for age and menopause, but was not significant after additional adjustment for body fatness. In summary, the findings of this study suggest that body fatness and CRF might modify the GNB3-mediated genetic susceptibility to elevated resting blood pressures in middle-aged Korean women.


Asunto(s)
Adiposidad/genética , Presión Sanguínea/genética , Proteínas de Unión al GTP Heterotriméricas/genética , Polimorfismo Genético , Adulto , Pueblo Asiatico/genética , Índice de Masa Corporal , Peso Corporal/genética , Femenino , Predisposición Genética a la Enfermedad , Humanos , Hipertensión/genética , Corea (Geográfico) , Persona de Mediana Edad , Obesidad/genética , Análisis de Regresión
2.
Clin Radiol ; 63(11): 1236-44, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18929041

RESUMEN

AIM: To evaluate the association between computed tomography (CT) detection of early gastric cancer (EGC) and various parameters, including the depth of invasion, lesion extent, morpholgical type, location, and histological type. MATERIALS AND METHODS: One hundred and ten patients with 114 EGCs were preoperatively examined using multidetector CT (MDCT). All patients received 500 ml water as an oral contrast agent approximately 15 min before the examination and an additional 500 ml immediately prior to the study. Portal venous phase, contrast-enhanced, helical scans with multiplanar reformation were obtained. All patients underwent surgery. For location and size of tumour, the CT findings were compared with the histopathological results. The association between CT detection of EGC and various parameters were assessed. In addition, we performed a stepwise forward logistic regression to identify which variables significantly increased the CT detection rate of EGC. RESULTS: The detection rate of all EGCs using MDCT was 36.4%. The detection rate for EGCs confined to the superficial layer (mucosa or SM1) was 14.3%, whereas the detection rate for EGCs that involved the deep layer (SM2 or more than SM2) was 86.5%. All three of the protruded lesions and five of the six excavated lesions were readily detected using CT. Stepwise forward logistic regression showed that the best parameter for CT detection of EGCs was the depth of invasion; more EGCs were detected when the lesion was deep. CONCLUSION: MDCT has advantages in acceptable evaluation of the depth invasion of EGCs. EGC that is undetectable using CT suggests an EGC confined to the superficial layer, whereas EGC detectable using CT suggests deep lesions.


Asunto(s)
Neoplasias Gástricas/diagnóstico por imagen , Neoplasias Gástricas/patología , Adulto , Anciano , Artefactos , Diagnóstico Precoz , Femenino , Mucosa Gástrica/patología , Gastroscopía , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
3.
Clin Radiol ; 63(7): 783-90, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18555036

RESUMEN

AIM: To evaluate the "transient gastric perfusion defect" sign as a way of diagnosing portal hypertensive gastropathy (PHG) on multidetector computed tomography (CT). MATERIALS AND METHODS: Ninety-two consecutive patients with cirrhosis underwent three-phase CT and endoscopy. Endoscopy was performed within 3 days of the CT examination. As controls, 92 patients without clinical evidence of chronic liver diseases who underwent CT and endoscopy were enrolled; the findings at endoscopy were used as a reference standard for patients with PHG. Two radiologists who were unaware of the results of the endoscopy retrospectively interpreted the CT images. PHG was diagnosed on dynamic CT if the transient gastric perfusion defect sign was present. The transient gastric perfusion defect was defined as the presence of transient, segmental or subsegmental hypo-attenuating mucosa in the fundus or body of the stomach on hepatic arterial imaging that returned to normal attenuation on portal venous or equilibrium-phase imaging. The frequency of the transient gastric perfusion defect sign was compared between these two groups using Fisher's exact test. The frequency, sensitivity, specificity, positive predictive values, and negative predictive values of the transient gastric perfusion defect sign were also compared between patients with PHG and without PHG in the cirrhosis group. RESULTS: Nine patients of 92 patients with cirrhosis were excluded because of previous procedure or motion artifact; the remaining 83 patients with cirrhosis were evaluated. In the cirrhosis group, 40 (48.1%) of 83 patients showed the transient gastric perfusion defect sign. In the control group, none of the 92 patients showed the transient gastric perfusion defect sign. In the cirrhotic group, the frequency of the transient gastric perfusion defect sign was significantly higher in the patients with PHG (75%, 36/48) than in patients without PHG (11.4%, 4/35). The sensitivity, specificity, positive predictive values, and negative predictive values of the sign for CT diagnosis of PHG in the cirrhosis group were 75, 88.6, 90, and 72.1% respectively. CONCLUSION: The transient gastric perfusion defect sign could be used as a relatively specific sign of PHG in patients with cirrhosis.


Asunto(s)
Circulación Enterohepática , Arteria Hepática/diagnóstico por imagen , Hipertensión Portal/diagnóstico por imagen , Cirrosis Hepática/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Gastroscopía , Humanos , Hipertensión Portal/complicaciones , Cirrosis Hepática/complicaciones , Masculino , Persona de Mediana Edad , Portografía/métodos , Estudios Retrospectivos , Sensibilidad y Especificidad
4.
Br J Radiol ; 80(953): e91-3, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17638838

RESUMEN

We report a case of calcified endobronchial leiomyoma in the left main bronchus. Leiomyoma of the airways is a rare benign tumour, usually described as a solitary lesion and located in the membranous portion of the lower third of the trachea and rarely in the bronchi. Chest CT showed a well-defined, calcified, polypoid endobronchial mass with a broad stalk in the left main bronchus.


Asunto(s)
Neoplasias de los Bronquios/diagnóstico por imagen , Calcinosis/diagnóstico por imagen , Leiomioma/diagnóstico por imagen , Anciano , Broncoscopía/métodos , Humanos , Masculino , Tomografía Computarizada por Rayos X/métodos , Tuberculosis Pulmonar/diagnóstico por imagen
5.
Neuroscience ; 124(1): 89-104, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-14960342

RESUMEN

Tonicity-responsive enhancer-binding protein (TonEBP) was initially identified as a transcription factor involved in adaptation of renal cells to hypertonicity by activation of osmoprotective genes encoding proteins for accumulation of compatible osmolytes. Since brain osmoadaptation is observed in relationship to neurological disorders resulting from pathological osmotic disbalances of blood plasma we have investigated through immunocytochemistry TonEBP expression in cerebral cortex and hippocampus of normal rat and rats submitted to an acute systemic hypertonicity or to a prolonged systemic hypotonicity. TonEBP-expressing cells were identified using double immunofluorescence and appropriate cell type markers. Their relative proportion was determined by quantitative image analysis. In normal rats TonEBP expressed primarily in neurons where it was strictly located in the cell nucleus but heterogeneously distributed into a nucleoplasmic pool and a granular pool. In animals made acutely hypertonic TonEBP labeling increased dramatically exclusively in the nuclei of neurons and reached a maximum within 1 h. In hypertonic animals TonEBP labeling covered the whole cell nucleus of virtually all neurons, appeared finely punctuated but was no more granular. Optical density of the labeling as determined by image analysis correlated linearly with the increased plasma osmolality. In animals made hypotonic for several days no conspicuous decrease of TonEBP labeling was observed. In normal animals a very minor proportion of non-neuronal cells showed a faint TonEBP nuclear labeling. This proportion increased slightly in hypertonic animals. Nevertheless these non-neuronal TonEBP-positive nuclei which belonged to oligodendrocytes and to a small subpopulation of astrocytes remained always very weakly labeled when compared with neuron nuclei. Brain capillary endothelial cells as well as microglial cells showed no TonEBP-labeling even in hypertonic animals. Our data demonstrate that in brain TonEBP is significantly expressed and tonicity-overexpressed in neurons and accordingly suggest that neurons only among brain cells accumulate compatible osmolytes through TonEBP-mediated activation of osmoprotective genes to adapt to acute systemic hypertonicity.


Asunto(s)
Corteza Cerebral/fisiología , Hipocampo/fisiología , Neuronas/metabolismo , Transactivadores/metabolismo , Equilibrio Hidroelectrolítico/fisiología , Animales , Corteza Cerebral/citología , Ingestión de Líquidos/fisiología , Expresión Génica/fisiología , Hipocampo/citología , Hipernatremia/fisiopatología , Soluciones Hipertónicas/farmacología , Inmunohistoquímica , Masculino , Ratas , Ratas Sprague-Dawley , Sacarosa/farmacología , Factores de Transcripción , Privación de Agua/fisiología , Intoxicación por Agua/fisiopatología
6.
Interv Neuroradiol ; 10(3): 231-4, 2004 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-20587235

RESUMEN

SUMMARY: We report the case of patient with bilateral and symmetrical aneurysms, mirror image, of the distal posterior cerebral artery (PCA) who presented with subarachnoid haemorrhage. The aneurysms were treated by endovascular approach using Guglielmi detachable coils (GDCs). A review of the pathophysiology, clinical manifestations and management of mirror aneurysms is presented and discussed.

7.
Ann Trop Med Parasitol ; 97(5): 481-7, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12930610

RESUMEN

Sera collected in South Korea, from 61 cases of Plasmodium vivax malaria and, as controls, 40 healthy volunteers, were tested in ELISA for IgG or IgM reacting with any of three recombinant P. vivax proteins. The antigens used, representing the parasite's major merozoite surface protein (MSP), circumsporozoite surface protein (CSP) and Duffy-binding protein (DBP), had all been expressed in an Escherichia coli system and purified. The ELISA results were recorded as optical densities (OD). The highest ratio observed between the mean OD for a malaria serum and that for a control serum was that for IgG against MSP, although CSP gave a higher ratio than MSP or DBP in the IgM ELISA. In the ELISA for IgG, the OD for MSP were found to be correlated with those for DBP (r = 0.53; P < 0.5) but the OD for CSP were not correlated with those for MSP or DBP. As the most intense reactions observed were those between the IgG from the malaria sera and the recombinant MSP, the latter antigen may be useful in diagnostic tests and as a component of any vaccine used to protect against P. vivax malaria.


Asunto(s)
Inmunoglobulina G/inmunología , Inmunoglobulina M/inmunología , Malaria Vivax/inmunología , Proteínas Protozoarias/inmunología , Adulto , Animales , Antígenos de Protozoos/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Humanos , Masculino , Proteínas de la Membrana/inmunología , Proteína 1 de Superficie de Merozoito/inmunología , Plasmodium vivax/inmunología , Reacción en Cadena de la Polimerasa/métodos , Receptores de Superficie Celular/inmunología , Proteínas Recombinantes/inmunología
8.
Am J Physiol Cell Physiol ; 280(6): C1465-74, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11350742

RESUMEN

The expression of the osmosensitive sodium/myo-inositol cotransporter (SMIT) is regulated by multiple tonicity-responsive enhancers (TonEs) in the 5'-flanking region of the gene. In response to hypertonicity, the nuclear abundance of the transcription factor TonE-binding protein (TonEBP) is increased, and the transcription of the SMIT gene is induced. Transport system A for neutral amino acids, another osmosensitive mechanism, is progressively stimulated if amino acid substrates are not present in the extracellular compartment. Under this condition, as in hypertonicity, cells shrink and mitogen-activated protein kinases are activated. We demonstrate here that a clear-cut nuclear redistribution of TonEBP, followed by SMIT expression increase and inositol transport activation, is observed after incubation of cultured human fibroblasts in Earle's balanced salts (EBSS), an isotonic, amino acid-free saline. EBSS-induced SMIT stimulation is prevented by substrates of system A, although these compounds do not compete with inositol for transport through SMIT. We conclude that the incubation in isotonic, amino acid-free saline triggers an osmotic stimulus and elicits TonEBP-dependent responses like hypertonic treatment.


Asunto(s)
Aminoácidos/farmacología , Proteínas Portadoras/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas de la Membrana , Piel/citología , Piel/metabolismo , Simportadores , Transactivadores/metabolismo , Adolescente , Transporte Biológico/efectos de los fármacos , Transporte Biológico/fisiología , Núcleo Celular/metabolismo , Tamaño de la Célula/efectos de los fármacos , Tamaño de la Célula/fisiología , Células Cultivadas , Fibroblastos/citología , Fibroblastos/metabolismo , Humanos , Inositol/metabolismo , Soluciones Isotónicas/farmacología , Masculino , Presión Osmótica , Solución Salina Hipertónica/farmacología , Sodio/metabolismo , Factores de Transcripción
9.
Cytotechnology ; 37(3): 179-87, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19002921

RESUMEN

The recombinant a and bsubunits for human coagulation factor XIII were transfected into Chinese hamster ovary (CHO) cells. CHO cells were amplified and selected with methotrexate in adherent cultures containing serum, and CHO 1-62 cells were later selected in protein-free medium. To develop a recombinant factor XIII production process in a suspension culture, we have investigated the growth characteristics of CHO cells and the maintenance of factor XIII expression in the culture medium. Suspension adaptation of CHO cells was performed in protein-free medium, GC-CHO-PI, by two methods, such as serum weaning and direct switching from serum containing media to protein-free media. Although the growth of CHO cells in suspension culture was affected initially by serum depletion, cell specific productivity of factor XIII showed only minor changes by the direct switching to protein-free medium during a suspension culture. As for the long-term stability of factor XIII, CHO 1-62 cells showed a stable expression of factor XIII in protein-free condition for 1000 h. These results indicate that the CHO 1-62cells can be adapted to express recombinant human factor XIII in a stable maimer in suspension culture using a protein-free medium. Our results demonstrate that enhanced cell growth in a continuous manner is achievable for factor XIII production in a protein-free medium when a perfusion bioreactor culture system with a spin filter is employed.

11.
Am J Physiol Renal Physiol ; 278(6): F1006-12, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10836989

RESUMEN

Tonicity-responsive enhancer binding protein (TonEBP) regulates transcription of tonicity responsive genes such as the sodium-myo-inositol cotransporter (SMIT), the sodium-chloride-betaine cotransporter (BGT1), and aldose reductase (AR). To characterize signals that activate TonEBP in Madin-Darby canine kidney (MDCK) cells, the abundance and nuclear distribution of TonEBP were studied after the osmolality of the culture medium was changed. Hypertonicity but not hyperosmolality is effective in activation of TonEBP as expected. Surprisingly, exposure to hypotonic medium leads to a dramatic downregulation of TonEBP both in abundance and nuclear distribution, indicating that under isotonic conditions, TonEBP is at a low-level activated state and can respond to both increase and decrease in tonicity. Additional experiments suggest that cellular ionic strength is the signal that initiates regulation of TonEBP. The increase in abundance of TonEBP is mediated by an increase in mRNA abundance and a parallel increase in synthesis of TonEBP. The stability of TonEBP mRNA is not affected by hypertonicity indicating that transcription plays a major role in the induction of TonEBP by hypertonicity.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Riñón/metabolismo , Proteínas de la Membrana , Simportadores , Factores de Transcripción/metabolismo , Animales , Proteínas Portadoras/genética , Línea Celular , Medios de Cultivo , Perros , Regulación hacia Abajo , Elementos de Facilitación Genéticos , Proteínas Transportadoras de GABA en la Membrana Plasmática , Proteínas de Choque Térmico/genética , Soluciones Hipertónicas , Soluciones Hipotónicas , Concentración Osmolar , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transducción de Señal , Regulación hacia Arriba
12.
AJR Am J Roentgenol ; 174(4): 1013-5, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10749241

RESUMEN

OBJECTIVE: The purpose of this study was to assess the value of the "daughter cyst" sign, a sonographic finding of neonatal ovarian cysts, in differentiating ovarian cysts from other cystic masses in neonates, infants, and young children. SUBJECTS AND METHODS: In a prospective study, 23 neonates, infants, and young children (age range, 1 day to 36 months) with a lower abdominal cystic mass underwent sonography. We defined the daughter cyst sign as the presence of a small cyst along the wall of a cystic mass. The diagnosis of ovarian cyst was made when this sign was present. Detailed pathologic correlation was available in four ovarian cysts. The size, wall thickness, and contents of the cysts were also evaluated. RESULTS: The 23 cystic lesions included ovarian cyst (n = 11), lymphangioma (n = 3), enteric duplication cyst (n = 3), enteric cyst (n = 1), meconium pseudocyst (n = 2), hydrometrocolpos (n = 2), and urachal cyst (n = 1). The daughter cyst sign was seen in nine (82%) of 11 ovarian cysts but in none of the other cystic lesions. Sensitivity, specificity, and positive predictive value of the daughter cyst sign for differentiating ovarian cysts from other cystic lesions were 82%, 100%, and 100%, respectively. The daughter cyst corresponded to an ovarian follicle on pathologic examination. CONCLUSION: The daughter cyst sign is a specific sonographic finding for an ovarian cyst and may be useful in differentiating uncomplicated ovarian cysts from other cystic masses in neonates, infants, and young children.


Asunto(s)
Quistes Ováricos/diagnóstico por imagen , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Lactante , Recién Nacido , Estudios Prospectivos , Ultrasonografía
13.
Am J Physiol Cell Physiol ; 278(2): C323-30, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10666027

RESUMEN

Tonicity-responsive enhancer binding protein (TonEBP) is the transcription factor that regulates tonicity-responsive expression of the genes for the sodium-myo-inositol cotransporter (SMIT) and the sodium-chloride-betaine cotransporter (BGT1). Hypertonicity stimulates the activity of TonEBP due to a combination of increased protein abundance and increased nuclear distribution (proportion of TonEBP that is in the nucleus). We found that inhibitors of proteasome activity markedly reduce the induction of SMIT and BGT1 mRNA in response to hypertonicity. These inhibitors also reduce hypertonicity-induced stimulation of expression of a reporter gene controlled by the tonicity-responsive enhancer. Western and immunohistochemical analyses revealed that the proteasome inhibitors reduce the hypertonicity-induced increase of TonEBP in the nucleus by inhibiting its nuclear redistribution without affecting its abundance. Although the nuclear distribution of TonEBP is sensitive to inhibition of proteasome activity as is that of nuclear factor (NF)-kappaB, the signaling pathways appear to be different in that hypertonicity does not affect the nuclear distribution of NF-kappaB. Conversely, treatment with tumor necrosis factor-alpha increases the nuclear distribution of NF-kappaB but not TonEBP.


Asunto(s)
Cisteína Endopeptidasas/metabolismo , Proteínas de la Membrana , Complejos Multienzimáticos/metabolismo , Simportadores , Transactivadores/metabolismo , Transcripción Genética/fisiología , Animales , Proteínas Portadoras/metabolismo , Línea Celular , Núcleo Celular/química , Núcleo Celular/enzimología , Núcleo Celular/genética , Cisteína Endopeptidasas/efectos de los fármacos , Inhibidores de Cisteína Proteinasa/farmacología , Perros , Elementos de Facilitación Genéticos/fisiología , Expresión Génica/efectos de los fármacos , Expresión Génica/fisiología , Glucano Endo-1,3-beta-D-Glucosidasa/metabolismo , Proteínas de Choque Térmico/metabolismo , Soluciones Hipertónicas/farmacología , Riñón/citología , Leupeptinas/farmacología , Complejos Multienzimáticos/efectos de los fármacos , FN-kappa B/análisis , Complejo de la Endopetidasa Proteasomal , ARN Mensajero/genética , Transactivadores/análisis , Transcripción Genética/efectos de los fármacos
14.
Proc Natl Acad Sci U S A ; 96(5): 2538-42, 1999 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-10051678

RESUMEN

Hypertonicity (most often present as high salinity) is stressful to the cells of virtually all organisms. Cells survive in a hypertonic environment by increasing the transcription of genes whose products catalyze cellular accumulation of compatible osmolytes. In mammals, the kidney medulla is normally hypertonic because of the urinary concentrating mechanism. Cellular accumulation of compatible osmolytes in the renal medulla is catalyzed by the sodium/myo-inositol cotransporter (SMIT), the sodium/chloride/betaine cotransporter, and aldose reductase (synthesis of sorbitol). The importance of compatible osmolytes is underscored by the necrotic injury of the renal medulla and subsequent renal failure that results from the inhibition of SMIT in vivo by administration of a specific inhibitor. Tonicity-responsive enhancers (TonE) play a key role in hypertonicity-induced transcriptional stimulation of SMIT, sodium/chloride/betaine cotransporter, and aldose reductase. We report the cDNA cloning of human TonE binding protein (TonEBP), a transcription factor that stimulates transcription through its binding to TonE sequences via a Rel-like DNA binding domain. Western blot and immunohistochemical analyses of cells cultured in hypertonic medium reveal that exposure to hypertonicity elicits slow activation of TonEBP, which is the result of an increase in TonEBP amount and translocation to the nucleus.


Asunto(s)
Regulación de la Expresión Génica , Médula Renal/fisiología , Transactivadores/genética , Transactivadores/metabolismo , Transcripción Genética , Secuencia de Aminoácidos , Animales , Sitios de Unión , Línea Celular , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Perros , Elementos de Facilitación Genéticos , Biblioteca de Genes , Células HeLa , Humanos , Soluciones Hipertónicas , Riñón/metabolismo , Mamíferos , Datos de Secuencia Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Solución Salina Hipertónica , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Transactivadores/química , Factores de Transcripción , Transfección
15.
Abdom Imaging ; 24(2): 202-4, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10024414

RESUMEN

We report the magnetic resonance appearance of a case of round ligament leiomyoma that presented as a rapid growing inguinal mass in a patient with Mayer-Rokitansky-Kuster-Hauser syndrome.


Asunto(s)
Enfermedades de los Anexos/diagnóstico , Leiomioma/diagnóstico , Imagen por Resonancia Magnética , Ligamento Redondo del Útero/patología , Anomalías Múltiples , Enfermedades de los Anexos/complicaciones , Femenino , Humanos , Leiomioma/complicaciones , Persona de Mediana Edad , Síndrome , Útero/anomalías , Vagina/anomalías
16.
Am J Physiol ; 274(4): F753-61, 1998 04.
Artículo en Inglés | MEDLINE | ID: mdl-9575900

RESUMEN

We have previously identified a tonicity-responsive enhancer (TonE) in the promoter region of the canine BGT1 gene. TonE mediates hypertonicity-induced stimulation of transcription. Here, we characterize TonE and TonE binding proteins (TonEBPs) to provide a biochemical basis for cloning of the TonEBPs. Mutational analysis applied to both hypertonicity-induced stimulation of transcription and TonEBP binding reveals that TonE is 11 base pairs in length, with the consensus sequence of (C/T)GGAAnnn(C/T)n(C/T). Activity of the TonEBPs increases in response to hypertonicity with a time course similar to that of transcription of the BGT1 gene. Studies with inhibitors indicate that translation, but not transcription, is required for activation of the TonEBPs. Phosphorylation is required for the stimulation of transcription but not for activation of DNA binding by the TonEBPs. In vivo methylation by dimethyl sulfate reveals that the TonE site of the BGT1 gene is protected with a time course like that of activity of the TonEBPs and activation of transcription. Ultraviolet cross-linking indicates that the TonEBPs share a DNA binding subunit of 200 kDa.


Asunto(s)
Proteínas Portadoras/genética , Soluciones Hipertónicas/farmacología , Transcripción Genética/efectos de los fármacos , Transcripción Genética/fisiología , Animales , Secuencia de Bases , Línea Celular , Perros , Elementos de Facilitación Genéticos/efectos de los fármacos , Proteínas Transportadoras de GABA en la Membrana Plasmática , Humanos , Riñón/citología , Datos de Secuencia Molecular , Mutación , Estereoisomerismo , Factores de Transcripción/genética
17.
Arch Biochem Biophys ; 347(1): 78-84, 1997 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-9344467

RESUMEN

Ubiquitin-specific protease-6 (UBP6) in Saccharomyces cerevisiae was expressed in Escherichia coli and purified from the cells using 125I-labeled ubiquitin-alphaNH-MHISPPEPESEEEEEHYC as a model substrate. The purified UBP6 behaved as a 58-kDa under both nondenaturing and denaturing conditions, indicating that the enzyme comprises a single polypeptide. It was maximally active at pH levels between 8.5 and 9, but showed little or no activity at pH below 7 and above 9.5. As with other UBPs, its activity was strongly inhibited by sulfhydryl-blocking reagents, such as N-ethylmaleimide, and by ubiquitin-aldehyde. In addition to the model substrate, UBP6 hydrolyzed ubiquitin-alphaNH-protein extensions, such as the ubiquitin-alphaNH-carboxyl extension protein of 80 amino acids and ubiquitin-alphaNH-dihydrofolate reductase, but not poly-His-tagged diubiquitin. It was also capable of releasing free ubiquitin from branched polyubiquitin chains that are ligated to proteins through epsilonNH-isopeptide bonds, although to a limited extent. These results suggest that UBP6 may play an important role in the generation of free ubiquitins and certain ribosomal proteins from ubiquitin-ribosomal fusion proteins as well as in deubiquitination of certain polyubiquitinated proteins targeted for degradation by the 26S proteasomes.


Asunto(s)
Endopeptidasas/aislamiento & purificación , Endopeptidasas/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/enzimología , Ubiquitinas/metabolismo , Secuencia de Aminoácidos , Western Blotting , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Endopeptidasas/química , Endopeptidasas/genética , Escherichia coli/genética , Concentración de Iones de Hidrógeno , Hidrólisis , Datos de Secuencia Molecular , Peso Molecular , Fragmentos de Péptidos/metabolismo , Inhibidores de Proteasas/química , Inhibidores de Proteasas/farmacología , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Especificidad por Sustrato , Ubiquitinas/análogos & derivados , Ubiquitinas/química , Ubiquitinas/farmacología
18.
Radiology ; 204(2): 481-4, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9240539

RESUMEN

PURPOSE: To evaluate with sonography the relationship of the ovary to the peritoneal inclusion cyst. MATERIALS AND METHODS: The medical records, sonograms, and sonographic reports of 15 premenopausal women with surgically proved peritoneal inclusion cysts were examined. Twelve of these cases were examined prospectively. In another prospectively evaluated case, the sonogram was interpreted as revealing a peritoneal inclusion cyst; however, hydrosalpinx was confirmed with surgery. Thirteen women with peritoneal inclusion cysts had undergone pelvic surgery before sonography. Additional examination with computed tomography was performed in three women and with magnetic resonance imaging in another. RESULTS: The ovary was detected on sonograms in 12 of 15 women with peritoneal inclusion cysts. In nine of the 12 women, the ovary was demonstrated to be inside the cyst. Ten of 12 ovaries appeared normal. Cyst diameter ranged from 7.5 to 17.4 cm (mean, 11.6 cm). Sonograms of two cysts demonstrated internal echoes. Septa were seen in 11 of the 15 cysts. Cysts were ovoid in six women and irregular in nine; they were defined by adjacent pelvic structures. CONCLUSION: In premenopausal women with a history of pelvic surgery, the appearance on sonograms of the ovary inside a large, ovoid or irregular, anechoic cyst is characteristic of a peritoneal inclusion cyst.


Asunto(s)
Quistes/diagnóstico por imagen , Ovario/diagnóstico por imagen , Enfermedades Peritoneales/diagnóstico por imagen , Adulto , Femenino , Humanos , Quistes Ováricos/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Estudios Prospectivos , Adherencias Tisulares/diagnóstico por imagen , Ultrasonografía
19.
Biochem J ; 325 ( Pt 2): 325-30, 1997 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-9230110

RESUMEN

We have previously shown that chick muscle extracts contained at least 10 different ubiquitin C-terminal hydrolases (UCHs). Here we report the purification and characterization of one of the UCHs, called UCH-8, with 125I-labelled ubiquitin-alpha-NH-MHISPPEPESEEEEEHYC as a substrate. The purified UCH-8 behaved as a 240 kDa protein on a Superdex-200 column under non-denaturing conditions but as a 130 kDa polypeptide on analysis by PAGE under denaturing conditions, suggesting that the enzyme consists of two identical subunits. Thus this enzyme seems to be distinct in its dimeric nature from other purified UCHs that consist of a single polypeptide, except that UCH-6 is also a homodimer of 27 kDa subunits. UCH-8 was maximally active between pH 7.5 and 8, but showed little or no activity below pH 7 and above pH 9. Like other UCHs it was sensitive to inhibition by thiol-blocking agents such as N-ethylmaleimide, and by ubiquitin aldehyde. The purified UCH-8 hydrolysed not only ubiquitin-alpha-NH-protein extensions, including ubiquitin-alpha-NH-carboxy extension protein of 80 amino acid residues and ubiquitin-alpha-NH-dihydrofolate reductase, but also branched poly-ubiquitin that are ligated to proteins through epsilon-NH-isopeptide bonds. However, it showed little or no activity against poly-His-tagged di-ubiquitin, suggesting that UCH-8 is not involved in the generation of free ubiquitin from the linear poly-ubiquitin precursors. These results suggest that UCH-8 might have an important role in the production of free ubiquitin and ribosomal proteins from their conjugates as well as in the recycling of ubiquitin molecules after the degradation of poly-ubiquitinated protein conjugates by the 26 S proteasome.


Asunto(s)
Isoenzimas/aislamiento & purificación , Músculos Pectorales/enzimología , Tioléster Hidrolasas/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Anticuerpos/inmunología , Cationes/farmacología , Pollos , Cromatografía en Gel , Concentración de Iones de Hidrógeno , Isoenzimas/química , Isoenzimas/metabolismo , Datos de Secuencia Molecular , Peso Molecular , Péptidos/química , Péptidos/metabolismo , Polilisina/farmacología , Inhibidores de Proteasas/farmacología , Especificidad por Sustrato , Tioléster Hidrolasas/química , Tioléster Hidrolasas/metabolismo
20.
J Biochem ; 121(4): 684-9, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9163518

RESUMEN

We have previously shown that chick muscle extracts contain at least 10 different ubiquitin C-terminal hydrolases (UCHs). In the present studies, one of the enzymes, called UCH-1 was partially purified by conventional chromatographic procedures using (125)I-labeled ubiquitin-alphaNH-MHISPPEPESEEEEEHYC as a substrate. The purified enzyme behaved as a 35-kDa protein under both denaturing and nondenaturing conditions, suggesting that it consisted of a single polypeptide chain. It was maximally active at pHs between 8 and 9, but showed little or no activity at pH below 6 and above 11. Like other UCHs, its activity was strongly inhibited by sulfhydryl blocking reagents, such as iodoacetamide, and by ubiquitin-aldehyde. In addition to Ub-PESTc, UCH-1 hydrolyzed ubiquitin-alphaNH-protein extensions, including ubiquitin-alphaNH-carboxyl extension protein of 80 amino acids, ubiquitin-alphaNH-dihydrofolate reductase, and poly-His-tagged di-ubiquitin. This enzyme was also capable of generating free ubiquitin from mono-ubiquitin-epsilonNH-protein conjugates and from branched poly-ubiquitin chains that are ligated to proteins through epsilon NH-isopeptide bonds. These results suggest that UCH-1 may play an important role in the generation of free ubiquitin from ubiquitin-ribosomal protein fusions and linear poly-ubiquitin, as well as in recycling of Ub molecules after degradation of poly-ubiquitinated protein conjugates by the 26S proteasome.


Asunto(s)
Liasas de Carbono-Nitrógeno , Músculo Esquelético/enzimología , Tioléster Hidrolasas/aislamiento & purificación , Tioléster Hidrolasas/metabolismo , Secuencia de Aminoácidos , Animales , Pollos , Cromatografía , Electroforesis , Concentración de Iones de Hidrógeno , Radioisótopos de Yodo , Yodoacetamida/farmacología , Liasas/metabolismo , Datos de Secuencia Molecular , Músculo Esquelético/química , Péptidos/química , Péptidos/metabolismo , Especificidad por Sustrato , Tioléster Hidrolasas/efectos de los fármacos , Ubiquitina Tiolesterasa , Ubiquitinas/metabolismo
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