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1.
Int J Clin Pract ; 59(5): 579-90, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15857355

RESUMEN

Benign prostatic hyperplasia is a common genitourinary disorder that increases in incidence with age. Symptoms of this condition include a weak urinary stream, hesitancy, intermittency and sensations of incomplete emptying, as well as frequency, urgency, urge incontinence and nocturia. These symptoms can be ameliorated successfully by a variety of medical treatments - such as alpha(1)-adrenergic blockade and 5-alpha-reductase inhibition - and surgical therapies - including transurethral resection of the prostate and less-invasive procedures. However, many of the treatments are known to result in sexual dysfunction, which can have a negative impact on the patient's quality of life. This must be considered when the physician seeks to determine the appropriate treatment for an individual patient. Current reports suggest that alpha(1)-adrenergic blockade is most likely to improve lower urinary tract symptoms while resulting in the fewest sexual side-effects; 5-alpha-reductase inhibitors appear to be particularly appropriate in men with large prostates. Among surgical therapies, transurethral resection of the prostate remains the gold standard, but is associated with a high incidence of sexual side-effects, especially retrograde ejaculation. Transurethral incision of the prostate, which is an endoscopic procedure, may be as effective as transurethral resection, but results in fewer side-effects. Minimally invasive procedures, including laser ablation or resection of the prostate, transurethral microwave thermotherapy and transurethral needle ablation, are rapidly evolving technologies that have demonstrated promising results, at least in the short term.


Asunto(s)
Disfunción Eréctil/etiología , Hiperplasia Prostática/cirugía , Calidad de Vida , Inhibidores de 5-alfa-Reductasa , Anciano , Ablación por Catéter , Disfunción Eréctil/tratamiento farmacológico , Humanos , Terapia por Láser , Masculino , Persona de Mediana Edad , Prostatectomía , Hiperplasia Prostática/complicaciones , Resección Transuretral de la Próstata/efectos adversos
2.
Neurosci Lett ; 313(1-2): 73-7, 2001 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-11684343

RESUMEN

The actions of melatonin on high-voltage activated calcium channels (HVACC) and intracellular free Ca(2+) concentration in cultured dorsal root ganglion (DRG) neurones from neonatal rats were investigated using the whole-cell patch clamp and the fura-2 fluorescence ratio Ca(2+)-imaging techniques. HVACC were pharmacologically and biophysically isolated and the effects of melatonin were investigated. Extracellular application of melatonin inhibited HVACC in a dose dependent manner. In calcium imaging experiments, application of extracellular recording medium containing 30 mM KCl evoked increases in intracellular free Ca(2+) that were dependent upon external Ca(2+) ions. This increase was prevented by both low (10 microM) and high dose (100 microM) of melatonin pre-treatment. The results of this study indicate that the pineal hormone melatonin has inhibitory actions on voltage dependent calcium entry in cultured rat DRG neurones.


Asunto(s)
Anticonvulsivantes/farmacología , Canales de Calcio/fisiología , Ganglios Espinales/citología , Melatonina/farmacología , Neuronas Aferentes/fisiología , Animales , Células Cultivadas , Colorantes Fluorescentes , Fura-2 , Potenciales de la Membrana/efectos de los fármacos , Neuronas Aferentes/efectos de los fármacos , Técnicas de Placa-Clamp , Potasio/farmacología , Ratas , Ratas Wistar
3.
Arch Phys Med Rehabil ; 80(9): 1065-71, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10489010

RESUMEN

OBJECTIVES: To investigate the effects of different interferential current (IC) and transcutaneous electrical nerve stimulation (TENS) frequencies on sensory, motor, and pain thresholds. STUDY DESIGN: Single blind, repeated measures design. SETTING: Laboratory. PARTICIPANTS: Women students 18 to 30 years old (n = 24). INTERVENTIONS: Premodulated IC and square-wave TENS pulses (125micros phase duration) were applied over the median nerve at a range of frequencies in all subjects. MAIN OUTCOME MEASURES: The peak current (in milliamperes) was recorded twice at each threshold for each frequency, and averaged. RESULTS: Both IC and TENS displayed a statistically significant effect of frequency for each threshold. However, frequency effects with IC were not well defined and were of small magnitude. Pure 4kHz current (0Hz amplitude modulated frequency) with IC did not produce effects different from those produced when an amplitude modulated frequency was included. With TENS, frequency effects were very clearly observed, with a distinct increase in the current intensity at each threshold as frequency decreased. CONCLUSIONS: It is postulated that the medium frequency component of IC is the main parameter in stimulation, contrary to traditional claims of the amplitude modulated frequency being important. TENS was shown to be a more adaptable method of stimulating these nerve pathways than IC.


Asunto(s)
Estimulación Eléctrica Transcutánea del Nervio/instrumentación , Adolescente , Adulto , Conductividad Eléctrica , Femenino , Humanos , Neuronas Motoras/fisiología , Músculo Esquelético/inervación , Umbral del Dolor/fisiología , Células Receptoras Sensoriales/fisiología , Umbral Sensorial/fisiología , Método Simple Ciego
4.
FEBS Lett ; 452(3): 199-204, 1999 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-10386590

RESUMEN

The protein RPE65 has an important role in retinoid processing and/or retinoid transport in the eye. Retinoids are involved in cell differentiation, embryogenesis and carcinogenesis. Since the kidney is known as an important site for retinoid metabolism, the expression of RPE65 in normal kidney and transformed kidney cells has been examined. The RPE65 mRNA was detected in transformed kidney cell lines including the human embryonic kidney cell line HEK293 and the African green monkey kidney cell lines COS-1 and COS-7 by reverse transcription PCR. In contrast, it was not detected in human primary kidney cells or monkey kidney tissues under the same PCR conditions. The RPE65 protein was also identified in COS-7 and HEK293 cells by Western blot analysis using a monoclonal antibody to RPE65, but not in the primary kidney cells or kidney tissues. The RPE65 cDNA containing the full-length encoding region was amplified from HEK293 and COS-7 cells. DNA sequencing showed that the RPE65 cDNA from HEK293 cells is identical to the RPE65 cDNA from the human retinal pigment epithelium. The RPE65 from COS-7 cells shares 98 and 99% sequence identity with human RPE65 at the nucleotide and amino acid levels, respectively. Moreover, the RPE65 mRNA was detected in three out of four renal tumor cultures analyzed including congenital mesoblastic nephroma and clear cell sarcoma of the kidney. These results demonstrated that transformed kidney cells express this retinoid processing protein, suggesting that these transformed cells may have an alternative retinoid metabolism not present in normal kidney cells.


Asunto(s)
Proteínas/genética , Transcripción Genética , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales , Secuencia de Bases , Células COS , Proteínas Portadoras , Bovinos , Línea Celular Transformada , Chlorocebus aethiops , ADN Complementario , Proteínas del Ojo , Humanos , Riñón , Datos de Secuencia Molecular , Biosíntesis de Proteínas , Proteínas/análisis , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Urodelos , cis-trans-Isomerasas
5.
Int J Clin Exp Hypn ; 44(4): 338-53, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8885532

RESUMEN

Researchers have attempted to find a method that accurately and reliably discriminates hypnotized individuals from those who are simulating hypnosis. Although an extensive literature exists in this area, researchers have failed to identify a discriminator that is consistently successful with a majority of the individuals who are tested. In the current study, 43 hypnotized and 37 simulating participants were categorized on the basis of their scores on the newly created Hypnotic Simulation Index (HSI). Using all 31 items of the HSI as predictors, 94% of the participants were correctly classified. In addition, a reduced set of only 15 items correctly classified 96% of the participants. These results suggest that the HSI is effective in discriminating hypnotized and simulating participants.


Asunto(s)
Hipnosis , Femenino , Humanos , Masculino
7.
In Vitro Cell Dev Biol Anim ; 30A(6): 356-65, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8087302

RESUMEN

Cell cultures were initiated from seven human fetal kidneys that varied in gestational age from 90 days to newborn. The growth medium utilized was a 1:1 mixture of Dulbecco's modified Eagle's and Ham's F12 supplemented with selenium (5 ng/ml), insulin (5 micrograms/ml), transferrin (5 micrograms/ml), hydrocortisone (36 ng/ml), triiodothyronine (4 pg/ml), and epidermal growth factor (10 ng/ml). For all the kidney isolates, initial cell attachment occurred within 12 h through multicell spheroids, and by 24 h a rapidly growing population of cells was obtained. Confluency was reached within 3 to 6 days. A combination of light microscopy, immunohistochemistry, and ultrastructural evaluation was utilized to characterize the resulting cultures as epithelial and homogeneous within each isolate and among the isolates. That is, regardless of gestational age of the fetal kidney used as starting material, an identical or highly similar population of cells was obtained. By light microscopy, the cultures were noted to form very few domes, the number being an indication of transport activity. However, ultrastructural examination revealed that the cells were noted to form domes composed of only a few cells or "micro-domes" that would not be visible by light microscopy. Within the micro-domes as well as other areas of the monolayer an apparent absence of tight junctions was noted by routine transmission electron microscopy. However, by freeze fracture analysis cells were shown to possess sealing strands, the structural component of tight junctions. It is postulated that the tight junctions of fetal epithelial cells are structurally altered as compared to tight junctions in adult renal epithelial cell cultures.


Asunto(s)
Edad Gestacional , Riñón/ultraestructura , Células Cultivadas , Medio de Cultivo Libre de Suero , Epitelio/embriología , Epitelio/enzimología , Epitelio/ultraestructura , Humanos , Inmunohistoquímica , Riñón/embriología , Riñón/enzimología , Microscopía Electrónica , ATPasa Intercambiadora de Sodio-Potasio/metabolismo
8.
Am J Pathol ; 142(3): 893-905, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8384407

RESUMEN

The ability to establish cell cultures representing the epithelial component of Wilms' tumor was determined for 18 cases of classic Wilms' tumors. From these 18 cases only two resulted in the culture of epithelial cells. Although the tumors from both cases were composed of a prominent epithelial component, other classic tumors not producing epithelial cell cultures also possessed appreciable epithelial components. Likewise, heterotransplants of these two primary tumors failed to give rise to epithelial cell cultures, although cultures of the blastemal element were produced. This suggests that Wilms' tumors may be prone to differentiate in different directions at varying times during tumor growth, possibly dependent on local tumor environment. Epithelial cells from these two classic cases were grown in culture in basal medium composed of a 1:1 mixture of Dulbecco's modified Eagle's medium and Ham's F-12 medium, supplemented with selenium, insulin, transferrin, hydrocortisone, tri-iodothyronine, and epidermal growth factor, on a collagen type I matrix with absorbed fetal calf serum proteins. One of the two cases also required the addition of bovine pituitary extract, ethanolamine, prostaglandin E1, and putrescine for optimum growth. Morphological analysis disclosed that the cultured cells were very similar to normal renal tubular cells in culture, except that the cells displayed little evidence for differentiated active ion transport and tended to grow in a multilayered arrangement. The culture of the epithelial cells from classic Wilms' tumors provides a model system for the study of tumor differentiation and progression.


Asunto(s)
Tumor de Wilms/patología , Animales , División Celular , Niño , Preescolar , Epitelio/patología , Epitelio/ultraestructura , Femenino , Humanos , Inmunohistoquímica , Lactante , Masculino , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Trasplante Heterólogo , Células Tumorales Cultivadas , Tumor de Wilms/ultraestructura
9.
Biochem J ; 282 ( Pt 3): 821-8, 1992 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-1554366

RESUMEN

1. Cell-free extracts of all plants tested contained a novel enzyme activity (xyloglucan endotransglycosylase, XET) able to transfer a high-Mr portion from a donor xyloglucan to a suitable acceptor such as a xyloglucan-derived nonasaccharide (Glc4Xyl3GalFuc; XG9). 2. A simple assay for the enzyme, using [3H]XG9 and based on the ability of the [3H]polysaccharide product to bind to filter paper, is described. 3. The enzyme was highly specific for xyloglucan as the glycosyl donor, and showed negligible transglycosylation of other polysaccharides, including CM-cellulose. 4. The Km for XG9 was 50 microM; certain other 3H-labelled xyloglucan oligosaccharides also acted as acceptors, and certain non-radioactive xyloglucan oligosaccharides competed with [3H]XG9 as acceptor; the minimum acceptor structure was deduced to be: [formula: see text] 5. The pH optimum was approx. 5.5 and the enzyme was less than half as active at pH 7.0. The enzyme was slightly activated by Ca2+, Mg2+, Mn2+, spermidine, ascorbate and 2-mercaptoethanol, and inhibited by Ag+, Hg2+, Zn2+ and La3+. 6. XET activity was essentially completely extracted by aqueous solutions of low ionic strength; Triton X-100, Ca2+, La3+, and Li+ did not enhance extraction. Negligible activity was left in the unextractable (cell-wall-rich) residue. 7. The enzyme differed from the major cellulases (EC 3.2.1.4) of pea in: (a) susceptibility to inhibition by cello-oligosaccharides, (b) polysaccharide substrate specificity, (c) inducibility by auxin, (d) requirement for salt in the extraction buffer and (e) activation by 2-mercaptoethanol. XET is therefore concluded to be a new enzyme activity (xyloglucan: xyloglucan xyloglucanotransferase; EC 2.4.1.-). 8. XET was detected in extracts of the growing portions of dicotyledons, monocotyledons (graminaceous and liliaceous) and bryophytes. 9. The activity was positively correlated with growth rate in different zones of the pea stem. 10. We propose that XET is responsible for cutting and rejoining intermicrofibrillar xyloglucan chains and that it thus causes the wall-loosening required for plant cell expansion.


Asunto(s)
Glucanos , Glicosiltransferasas/metabolismo , Proteínas de Plantas/metabolismo , Plantas/enzimología , Xilanos , Secuencia de Carbohidratos , Pared Celular/enzimología , Celulasa/metabolismo , Fabaceae/enzimología , Datos de Secuencia Molecular , Desarrollo de la Planta , Plantas Medicinales , Polisacáridos/metabolismo , Especificidad por Sustrato
10.
S Afr Med J ; 79(5): 271-4, 1991 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-1901428

RESUMEN

Katayama fever or acute schistosomiasis probably occurs more commonly than is recorded. Interviews with a 3-man scuba diving team who had had contact with a large dam in an endemic area of the eastern Transvaal Lowveld at the same time and contact area on the same day during late summer of 1986 are discussed. Two, who had not previously been exposed to infected water, presented with Katayama fever, due to Schistosoma mansoni infection, 21 days after contact and it took 30-36 months for them to recover fully after several treatments. The third patient, a keen water-sportsman and resident in the endemic area for a period of 10 years, presented with a mild infection, probably due to acquired immunity initiated during previous contacts with infected water; he took about a year to recover. The pathogenesis, clinical features, diagnosis and treatment of the 3 cases are described in the light of recent observations made elsewhere on Katayama fever cases and the effects of chemotherapy on the course of illness. The necessity of obtaining basic information on the travel and water-contact activities of patients in order to make a diagnosis is emphasised.


Asunto(s)
Buceo , Esquistosomiasis mansoni/etiología , Enfermedad Aguda , Adulto , Agua Dulce , Homeopatía , Humanos , Masculino , Prurito/etiología , Esquistosomiasis mansoni/epidemiología , Esquistosomiasis mansoni/patología , Esquistosomicidas/uso terapéutico , Sudáfrica/epidemiología , Factores de Tiempo
12.
In Vitro Cell Dev Biol ; 24(6): 593-600, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2455705

RESUMEN

The recognized need for epithelial cell culture models for cystic fibrosis (CF) research has resulted in ongoing efforts to improve normal and CF submandibular duct cell culture capabilities. The duct is most likely the site of the CF defect in this and other exocrine glands. In a previous report conditions required for the successful primary explant culture of normal and CF submandibular glands were outlined; however, terminal keratinization and involution of these cultures were recognized as severe limiting factors to their utilization in CF research. This report explores the effects of calcium concentrations in the medium, growth factor supplements, and matrix components on growth and differentiation of these cultures. Results of the study further confirm the ductal origin of cells in the outgrowth and demonstrate that progressive keratinization is initiated only after cells proliferate beyond the environment of the explant fragment. Keratinization with subsequent multilayering, desmosome formation, and involution in the cell outgrowth are governed in degree by the calcium concentration of the growth medium. Upon reduction of medium calcium to 0.1 mM concentration, the cells proliferate as a monolayer and subculture through 8 to 9 passages and retain the capacity to undergo ductlike differentiation.


Asunto(s)
Calcio/farmacología , Fibrosis Quística/patología , Glándula Submandibular/ultraestructura , Sangre , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Núcleo Celular/ultraestructura , Células Cultivadas , Colágeno , Medios de Cultivo , Desmosomas/ultraestructura , Humanos , Inmunohistoquímica , Queratinas/metabolismo , Laminina , Microscopía Electrónica , Microvellosidades/ultraestructura , Organoides/ultraestructura , Glándula Submandibular/efectos de los fármacos
13.
Arch Surg ; 121(5): 559-64, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-3085636

RESUMEN

The adverse effects of albumin resuscitation on coagulation activity, cardiopulmonary function, and extravascular flux of nonalbumin protein have made fresh-frozen plasma (FFP) an attractive alternate volume expander for hemorrhagic shock. This study addresses the effects of FFP on cardiopulmonary hemodynamics and protein flux. Whole blood was collected three and six weeks before shock, separated into red blood cells (PRBCs) and FFP, and stored. In 24 conditioned splenectomized dogs, resuscitation from reservoir shock of two hours' duration consisted of autologous PRBCs and balanced electrolyte solution (BES) in control dogs and PRBCs, BES, and FFP in plasma-treated dogs. Hemorrhagic shock reduced serum albumin and IgG levels in both groups. Resuscitation with FFP led to a higher cardiac output, left ventricular stroke work (LVSW), and pulmonary capillary wedge pressure (PCWP). The PCWP/LVSW ratio was comparable for both groups. Postshock day 2 serum albumin and IgG levels and lymphatic albumin and IgG concentrations were increased in plasma dogs. Therefore, FFP supplement to PRBC and BES resuscitation does not derange the PCWP/LVSW ratio or reduce intravascular nonalbumin proteins.


Asunto(s)
Proteínas Sanguíneas/análisis , Transfusión de Sangre Autóloga , Hemodinámica , Plasma , Resucitación/métodos , Choque Hemorrágico/terapia , Albúminas/análisis , Animales , Presión Sanguínea , Gasto Cardíaco , Perros , Transfusión de Eritrocitos , Frecuencia Cardíaca , Hematócrito , Cadenas gamma de Inmunoglobulina/análisis , Linfa/análisis , Presión Esfenoidal Pulmonar , Albúmina Sérica/análisis , Choque Hemorrágico/sangre , Choque Hemorrágico/fisiopatología
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