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1.
Acta Radiol ; 44(2): 160-1, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12694101

RESUMO

Adrenal cortical carcinoma (ACC) is a rare malignancy. Patients present either with a functional tumor or secondary to mass effect. In non-functioning tumors, the tumor size often exceeds 5 cm by the time of diagnosis, and tumor thrombus can occur. We report on a case of a small non-functioning ACC causing a large tumor thrombus in the inferior vena cava.


Assuntos
Neoplasias do Córtex Suprarrenal/patologia , Carcinoma Adrenocortical/secundário , Células Neoplásicas Circulantes , Veia Cava Inferior , Humanos , Masculino , Pessoa de Meia-Idade
2.
J Clin Endocrinol Metab ; 86(2): 855-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11158057

RESUMO

Testosterone is converted to dihydrotestosterone by 5 alpha-reductase2 in the prostate. Dihydrotestosterone controls cell division, and interindividual differences in prostatic 5 alpha-reductase 2 expression and activity may be a determinant of the risk of developing prostate cancer. However, little is known about interindividual differences in intraprostatic hormonal activity in vivo. To determine whether 5 alpha-reductase-specific messenger RNA (mRNA) is predictive of 5 alpha-reductase activity in prostatic tissue, we analyzed 30 prostatic tissue specimens from 15 Caucasian patients, 47--82 yr old. The mRNA was measured by RT-PCR. Five specimens consisted of cancer, whereas the remaining 25 were derived from benign prostate hyperplasia (BPH). We found a strong association between enzyme activity at pH 5.5 and the 5 alpha-reductase 2-specific mRNA expression when expressed on the basis of beta-actin [Spearman's rank-correlation coefficient (r(s)) = 0.81; 95% confidence interval, 0.64-0.91; P < 0.0001]. The expression of 5 alpha-reductase 2-specific mRNA in the cancer specimens was significantly lower than in the BPH tissue (P = 0.03). There was no difference in the expression of 5 alpha-reductase 1-specific mRNA in the cancer specimens, compared with BPH (P = 0.56). The strong association between 5 alpha-reductase activity at pH 5.5 and the 5 alpha-reductase 2-specific mRNA expression makes it possible to predict prostatic 5 alpha-reductase activity using core needle biopsies.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Próstata/enzimologia , Hiperplasia Prostática/enzimologia , Neoplasias da Próstata/enzimologia , RNA Mensageiro/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Concentração de Íons de Hidrogênio , Cinética , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/genética , Neoplasias da Próstata/genética , Suécia , População Branca
3.
Eur J Biochem ; 267(23): 6875-82, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11082199

RESUMO

Two cytochalasin B-binding states of the human red blood cell facilitative glucose transporter GLUT1 were studied, one exhibiting one cytochalasin B-binding site on every second GLUT1 monomer (state 1) and the other showing one site per monomer (state 2). Quantitative affinity chromatography of cytochalasin B was performed on (a) biotinylated red blood cells, (b) cytoskeleton-depleted red blood cell membrane vesicles, and (c) GLUT1 proteoliposomes. The cells were adsorbed on streptavidin-derivatized gel beads, and the vesicles and proteoliposomes entrapped in dextran-grafted agarose gel beads. Cytochalasin B binding to free vesicles and proteoliposomes was analyzed by Hummel and Dreyer size-exclusion chromatography and ultracentrifugation. Analysis of the biotinylated cells indicated an equilibrium between the two GLUT1 states. GLUT1 in free membrane vesicles attained state 2, but was converted into state 1 on entrapment of the vesicles. Purification of GLUT1 in the presence of non-ionic detergent followed by reconstitution produced GLUT1 in state 1. This state was maintained after entrapment of the proteoliposomes. Finally, GLUT1 showed slightly higher affinity for cytochalasin B in state 1 than in state 2. In summary, the cytochalasin B-binding state of GLUT1 seemed to be affected by (a) biotinylation of the cell surface, (b) removal of the cytoskeleton at high pH and low ionic strength, (c) interaction between the dextran-grafted agarose gel matrix and the membrane vesicles, and (d) reconstitution to form proteoliposomes.


Assuntos
Citocalasina B/química , Proteínas de Transporte de Monossacarídeos/química , Proteínas de Transporte de Monossacarídeos/metabolismo , Sítios de Ligação , Transporte Biológico , Biotinilação , Cromatografia de Afinidade , Citoesqueleto/metabolismo , Eritrócitos/metabolismo , Transportador de Glucose Tipo 1 , Humanos , Cinética , Modelos Biológicos , Ligação Proteica , Proteolipídeos/metabolismo , Sefarose/metabolismo , Fatores de Tempo , Ultracentrifugação
4.
Acta Radiol ; 41(4): 361-6, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10937759

RESUMO

PURPOSE: The fast helical CT technique allows examination of the kidneys during different phases of contrast medium enhancement. However, every additional phase increases the radiation dosage to the patients. We investigated the detection rate and characterisation of renal lesions during different phases and evaluated them separately, and considered the possibility of excluding phases without loss of important information. MATERIAL AND METHODS: Sixty patients who underwent contrast-enhanced multiphasic renal helical CT examination were included. Every CT phase was evaluated separately. The number of lesions and the characteristics of the lesions were noted and all lesions were viewed together. RESULTS: A total of 153 cysts and 17 solid lesions were detected. The largest and an equal number of cysts (142/143) was detected in the nephrographic and excretory phases. However, the nephrographic phase detected more cortical cysts and the excretory phase detected more sinus cysts. All solid lesions were detected in all phases. Renal parenchymal tumours were best characterised in the cortical phase and angiomyolipomas in the native phase. CONCLUSION: The cortical phase was best for characterisation of renal parenchymal tumours. The nephrographic and excretory phases were best in detecting and characterising renal cysts. The nephrographic phase was the phase giving the least diagnostic information.


Assuntos
Nefropatias/diagnóstico por imagem , Rim/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Doenças Renais Císticas/diagnóstico por imagem , Neoplasias Renais/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade
5.
J Clin Endocrinol Metab ; 82(7): 2210-4, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9215296

RESUMO

Androgens are implicated in the development of prostate cancer (CAP) and benign prostate hyperplasia. The conversion of testosterone to the more potent metabolite dihydrotestosterone by prostatespecific steroid 5 alpha-reductase type 2 (5 alpha-red2) is a key mechanism in the action of androgens in the prostate and is important in the promotion and progression of prostate diseases. Manipulation of the turnover of androgens is thus fundamental in the pharmacological treatment strategy. We have developed a sensitive solution hybridization method for quantification of the gene expression of 5 alpha-red2 in core needle biopsies of the prostate. The 5 alpha-red2-specific messenger RNA (mRNA) levels were measured in 50 human prostate transrectal ultrasound-guided core biopsies obtained from 31 outpatients (median age 72, range 67-88 yr) undergoing biopsy for diagnostic purposes. Significant differences were observed in the gene expression of 5 alpha-red2 between cancerous and noncancerous tissue. In the 14 biopsies judged cancerous, the median 5 alpha-red mRNA levels were 3.5 amol/ng total RNA compared with 12.0 amol/ng total RNA in the biopsies showing no cancer (P = 0.0018). The median 5 alpha-red2 mRNA level in noncancerous tissue was thus 3.4 times higher than in the cancerous specimens.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Biópsia por Agulha/métodos , Hiperplasia Prostática/metabolismo , Neoplasias da Próstata/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/patologia , RNA Mensageiro/metabolismo
6.
Biochim Biophys Acta ; 1325(1): 91-8, 1997 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-9106486

RESUMO

Chromatography on a novel stationary phase, human red cells immobilized in a gel bed, was introduced for analysis of activities of the glucose transporter Glut1 in the cell membrane. A gel containing positively charged ligands was synthesized from derivatized acrylamide monomers. Red cells were immobilized in gel particles which were packed into a column tube for chromatographic analyses over periods of 10-15 days. D-Glucose was separated from L-glucose on a 1.1-ml bed with a retention volume difference of 0.23 ml, approximately equal to the total inner volume of immobilized intact cells and of ghosts probably formed from lysed cells during the immobilization. The separation was suppressed by the glucose-transport inhibitor cytochalasin B. The interactions between D-glucose, the transport inhibitor forskolin and Glut1 were analyzed by quantitative frontal affinity chromatography. The dissociation constants at room temperature were 6.8 mM for D-glucose binding and 1.8 microM for glucose-displaceable binding of forskolin, in good agreement with published values. The results suggest that chromatography on immobilized cells is a potentially useful tool for studies on cellular membrane functions.


Assuntos
Cromatografia/métodos , Eritrócitos/metabolismo , Glucose/metabolismo , Proteínas de Transporte de Monossacarídeos/metabolismo , Resinas Acrílicas , Transporte Biológico , Células Imobilizadas , Colforsina/farmacologia , Glucose/isolamento & purificação , Transportador de Glucose Tipo 1 , Humanos , Proteínas de Transporte de Monossacarídeos/antagonistas & inibidores , Estereoisomerismo
7.
Scand J Urol Nephrol ; 31(6): 529-32, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9458509

RESUMO

In a questionnaire survey of urological departments in Sweden, Denmark, Finland and Norway, 20 episodes of perforation of continent urinary pouches were found to have occurred in 18 patients, representing an incidence of 1.5%. This complication occurred with ileal as well as colonic segments, without predilection. In one case there was perforation of an appendiceal outlet. Noticeable findings were (a) a long delay (median 10h) to treatment and (b) that investigational procedures such as enterocystography and enterocystoscopy were not commonly employed. Treatment of this potentially lethal complication was by oversewing the perforation, and there were no subsequent major complications. This complication should be strongly suspected if a patient with continent urinary reconstruction presents with acute abdominal pain.


Assuntos
Dor Abdominal/etiologia , Complicações Pós-Operatórias , Coletores de Urina/efeitos adversos , Adulto , Idoso , Feminino , Humanos , Laparotomia , Masculino , Pessoa de Meia-Idade , Proctocolectomia Restauradora/efeitos adversos , Ruptura Espontânea , Bexiga Urinária/cirurgia , Neoplasias da Bexiga Urinária/cirurgia
8.
Scand J Urol Nephrol ; 30(6): 473-7, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9008028

RESUMO

Telephone interviews concerning urinary continence and sexual potency in 152 men who had undergone radical prostatectomy for localized cancer were conducted by an investigator who had not been involved in the patients' treatment. The obtained data were compared with the surgeons' recorded follow-up notes. Continence was defined according to ICS criteria and potency as the capacity for vaginal penetration. At the interviews, 74 men (49%) reported total continence and 39 others (26%) were acceptably dry; 32 required more than two small protective pads per day, five had received an artificial sphincter implant and two had supravesical urinary diversion (Kock pouch), making 39 (25%) classified as incontinent. The surgeons' records, however, showed an 89% continence rate and 87% of these men had regained continence within 24 weeks of the operation. Of 134 preoperatively potent men, only 21 (14%) remained potent in the first postoperative year. That earlier reported excellent results regarding continence and potency were not reproduced in our study, possible was partly due to our inclusion of more advanced tumours in somewhat older patients, but the fact that the interviewer was independent of the surgeon significantly influenced the results.


Assuntos
Disfunção Erétil/etiologia , Complicações Pós-Operatórias/etiologia , Prostatectomia , Neoplasias da Próstata/cirurgia , Incontinência Urinária/etiologia , Idoso , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/mortalidade , Taxa de Sobrevida , Coletores de Urina , Esfíncter Urinário Artificial
9.
Biochemistry ; 35(37): 12141-5, 1996 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-8810921

RESUMO

Human red cell membrane vesicles stripped of peripheral proteins and proteoliposomes with reconstituted red cell glucose transporter (Glut1) were sterically immobilized in gel beads by freezethawing. The specific interactions between the transport inhibitor cytochalasin B (CB), D-glucose, and Glut1 were analyzed by quantitative frontal affinity chromatography. The dissociation constants, Kd(CB), for the interaction between CB and Glut1 in vesicles and proteoliposomes were similar, the average value being 92 +/- 5 nM at an ionic strength I of 0.05. Kd(CB) for Glut1 in vesicles decreased with increasing ionic strength to become 46 nM at I = 0.5. The affinity of glucose was significantly higher for Glut1 in vesicles (Kd = 24 +/- 2 mM) than for reconstituted Glut1 (Kd = 37 +/- 2 mM). The frontal analysis allowed determination of the amount of CB binding sites, which was found to be 0.33 +/- 0.06 mol per mole of Glut1 monomer (Mr = 54 000). The CB binding capacity of Glut1 in the vesicles and the proteoliposomes was stable in the presence of dithioerythritol over periods of several weeks at room temperature.


Assuntos
Citocalasina B/metabolismo , Membrana Eritrocítica/metabolismo , Glucose/metabolismo , Proteínas de Transporte de Monossacarídeos/sangue , Proteínas de Transporte de Monossacarídeos/isolamento & purificação , Proteolipídeos/metabolismo , Sítios de Ligação , Cromatografia de Afinidade/métodos , Cromatografia em Gel , Transportador de Glucose Tipo 1 , Humanos , Cinética , Proteínas de Transporte de Monossacarídeos/química , Concentração Osmolar , Ligação Proteica
10.
Biochim Biophys Acta ; 1282(1): 39-47, 1996 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-8679658

RESUMO

The self-association state of the human red cell glucose transporter (Glut1) in octaethylene glycol n-dodecyl ether (C12E8) and n-octyl beta-D-glucopyranoside (OG) solution was analyzed in the presence of reductant by gel filtration with light-scattering, refractivity and absorbance detection, and by ultracentrifugation. The C12E8-Glut1 complex was essentially monomeric, whereas OG-Glut1 also formed dimers and larger oligomers. C12E8-Glut1 retained substantial glucose transport activity even after depletion of endogenous lipids by gel filtration, as shown by reconstitution and transport measurements. Removal of endogenous lipids from OG-Glut1 abolished the activity unless phosphatidylcholine was included in the eluent. The binding of C12E8 and OG to Glut1 was determined by gel filtration with refractivity and absorbance detection or with radioactive tracer to be 1.86 +/- 0.07 and 1.84 +/- 0.09 g/g polypeptide, respectively. A structural model was proposed in which non-ionic detergent forms a semi-elliptical torus (SET) surrounding the transmembrane protein. The torus thickness was assumed to be equal to the radius (short half-axis) of a spherical (oblate ellipsoidal) free detergent micelle and the polar head groups of the detergent molecules were predicted to be situated just outside the hydrophobic surface of the protein. The experimental detergent binding values and those obtained from the SET model together confirmed that Glut1 was monomeric in C12E8 solution and provided constraints on the shape and size of the hydrophobic transmembrane region of Glut1 in alpha-helical and beta-barrel topology models.


Assuntos
Detergentes/metabolismo , Eritrócitos/metabolismo , Proteínas de Membrana/sangue , Proteínas de Transporte de Monossacarídeos/sangue , Transporte Biológico , Cromatografia em Gel , Transportador de Glucose Tipo 1 , Glucosídeos/metabolismo , Humanos , Substâncias Macromoleculares , Matemática , Modelos Químicos , Proteínas de Transporte de Monossacarídeos/química , Polietilenoglicóis/metabolismo , Estrutura Secundária de Proteína , Soluções , Ultracentrifugação
11.
Inflammation ; 18(1): 99-105, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8206648

RESUMO

The production of oxygen metabolites is probably important in cancer cell killing. The production of the superoxide anion, O2-, can be measured by lucigenin-enhanced chemiluminescence (Cl). Previous studies have shown that whole-blood lucigenin-enhanced Cl is increased in cancer patients and that this increase is related to blood monocyte activity. The present investigation confirmed these findings and showed that whole-blood lucigenin-enhanced Cl was elevated in 17 patients with renal cell adenocarcinoma (P < 0.001). The activity of the monocytes was studied more in detail, whereby monocytes were separated into different populations based upon differences in densities, i.e., high-density and low-density monocytes. The cancer patients had a significantly larger proportion of high-density monocytes (P < 0.05) than controls. The lucigenin-enhanced Cl of purified high-density monocytes in controls was significantly higher than that of low-density monocytes (P < 0.01). The authors conclude that the increase in the lucigenin-enhanced Cl of whole blood observed in cancer patients may partly reflect the increased activity of a larger proportion of high-density monocytes in these patients.


Assuntos
Carcinoma de Células Renais/sangue , Monócitos , Acridinas , Adulto , Idoso , Idoso de 80 Anos ou mais , Contagem de Células Sanguíneas , Feminino , Humanos , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Oxirredução , Superóxidos/metabolismo
12.
Biochim Biophys Acta ; 1150(2): 135-46, 1993 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-8347668

RESUMO

The facilitative glucose transporter Glut 1 from human red cells was reconstituted into liposomes that were size-fractionated and immobilized in an octyl sulfide-Sephacryl S-1000 column. D-[14C]Glucose was eluted later than L-[3H]glucose from the Glut 1 liposome column (by delta V microliters), apparently because the D-glucose was transported through the liposomes. The corresponding difference with protein-free liposomes was delta V0. The Glut 1 transport retention chromatographic effect, delta VG = delta V - delta V0, 40-50 microliters at pH 7, was nearly constant at pH 6-10 (400 mM NaCl, 23 degrees C, internal liposome volume approximately 240 microliters) but decreased steeply below pH 5 to become zero at pH 3.6. The decrease corresponded to a pKa of approximately 4.4 and was partly reversible above pH 4.7. Similarly, glucose exchange by non-immobilized freeze-thawed proteoliposomes with Glut 1 slowed down drastically as the pH was lowered from pH 5.5 to 4; and octyl glucoside-solubilized Glut 1 lost half its activity in 15 min at pH 4.5 (low ionic strength, 2 degrees C) as shown by glucose exchange determinations at pH 7.2 The results suggest that Glut 1 is inactivated at low pH upon protonation of carboxylate groups of pKa approximately 4.4-4.8. It seems likely that carboxylate groups form hydrogen bonds to transported D-glucose.


Assuntos
Eritrócitos/metabolismo , Glucose/metabolismo , Lipossomos/metabolismo , Proteínas de Transporte de Monossacarídeos/metabolismo , Proteínas de Transporte/metabolismo , Cromatografia , Humanos
14.
Eur Urol ; 22(4): 271-7, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1283370

RESUMO

The effects of finasteride, a potent 5 alpha-reductase inhibitor, were assessed in patients with benign prostatic hyperplasia. Patients were treated with finasteride or placebo for 24 weeks in a double-blind multicenter study followed by a 12-month open-extension period. After 24 weeks, finasteride-treated patients, when compared to placebo-treated patients, showed a significant reduction in prostate volume (22.5% median decrease) and prostate significant antigen (32.4% median decrease), a significant increase in maximum urinary flow (1.6 ml/s mean increase from baseline) and a significant improvement in their obstructive symptom scores (two-point decrease from baseline). Finasteride was well tolerated, and the improvements in prostate volume, maximum urinary flow rate and obstructive symptom scores observed in the controlled study were maintained throughout the extension study.


Assuntos
Inibidores de 5-alfa Redutase , Androstenos/uso terapêutico , Azasteroides/uso terapêutico , Hiperplasia Prostática/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Di-Hidrotestosterona/metabolismo , Método Duplo-Cego , Finasterida , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Osteocalcina/efeitos dos fármacos , Antígeno Prostático Específico/efeitos dos fármacos , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/fisiopatologia , Países Escandinavos e Nórdicos , Testosterona/metabolismo , Micção/efeitos dos fármacos
15.
J Urol ; 146(1): 24-7, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2056598

RESUMO

To evaluate the influence of the volume of 2% lidocaine jelly as an anesthetic during cystoscopy 241 men and women received either 11 or 20 ml. jelly intraurethrally in a randomized, double-blind fashion. Pain was recorded on a visual analogue scale by the patient and on a 3-level scale by the physician. The pain scores according to the visual analogue scale were significantly higher in the patients given 11 ml. jelly than in those given 20 ml. when all patients in the study were analyzed. There was no significant difference in the visual analogue scale between the 2 treatments in women but a significant difference was noted in men, although in men older than 55 years the difference was not statistically significant. There was general agreement between the visual analogue scale results and the physician scores but the visual analogue scale procedure was more sensitive in detecting differences between treatments. It is suggested that approximately 11 ml. 2% lidocaine jelly is the appropriate volume for women and 20 ml. is the appropriate volume for men during cystoscopy but that the lower volume of jelly may be sufficient in older men.


Assuntos
Anestesia Local/métodos , Cistoscopia/métodos , Lidocaína/administração & dosagem , Dor/prevenção & controle , Envelhecimento , Cistoscópios , Feminino , Géis , Humanos , Lubrificação , Masculino , Dor/diagnóstico , Dor/etiologia , Medição da Dor/métodos , Caracteres Sexuais
17.
Scand J Urol Nephrol Suppl ; 114: 87-90, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3201172

RESUMO

The sensory pathways innervating the male urethra were investigated by recording the sensory thresholds with electrical stimulation. Twenty-six male subjects (age 16 to 73 years) were included in the study. Ring-electrodes mounted on a Foley catheter were used for stimulation in proximal and distal urethra. Square wave pulses (duration 0.5 ms) were delivered with a constant current stimulator at different frequencies and the lowest intensity felt by the subject was defined as the threshold. The sensory thresholds were in the order of 0.5 to 5 mA and decreased with increasing stimulation frequency. All patients described a qualitative difference in the experienced sensation when comparing proximal and distal urethral stimulation. The reason for this is discussed. The possible use of this method as an adjunct to the urodynamic investigation in diagnosing neurogenic lesions is proposed.


Assuntos
Uretra/inervação , Micção , Urodinâmica , Adolescente , Adulto , Vias Aferentes/anatomia & histologia , Idoso , Estimulação Elétrica , Humanos , Masculino , Pessoa de Meia-Idade , Sensação/fisiologia , Limiar Sensorial
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