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J Reventós

Publications and source records attributed to J Reventós.

32 records · Page 2Linked to original sources
PubMed1995

Androgen binding protein is tissue-specifically expressed and biologically active in transgenic mice.

In view of the inconclusive data concerning the role of androgen-binding protein (ABP) in male reproductive physiology, we thought it would be pertinent to make several transgenic mouse lines overexpressing the rat ABP gene to unravel its role in Sertoli cell and epididymal homeostasis. Heterozygote transgenic mouse lines carrying the 5.5 kb ABP rat genomic DNA were produced by pronuclear microinjection. Northern blot analysis showed overexpression of rat ABP (rABP) mRNA in the testis of transgenic mice compared to rat testis control. rABP was appropriately expressed in Sertoli cells as demonstrated by in situ hybridization analysis. Sertoli cell number is increased in the seminiferous tubules of mice overexpressing rABP compared to non-transgenic littermates and scattered Sertoli cells present vacuolated-like cytoplasms, PAS and osmium negative. Compared to the wild type, the transgenic mice exhibited reduced fertility and focal damage in seminiferous epithelium characterized by morphological features compatible with programmed cell death.

Androgen-Binding Protein↗
PubMed1990

Studies on steroid binding proteins in normal tissues and tumor cell lines.

Steroid binding proteins bind steroid hormones with high affinity and their function is to carry those hormones in the extracellular compartment. Since their discovery more than fifty years ago, many reports concerning their physicochemical structures and functions have contributed to the better understanding of those proteins. Recent advances in recombinant DNA technology have led to the availability of molecular probes for these proteins, and new approaches have been used to analyse their gene structures as well as the regulation of their synthesis. In the present report, we will review the new findings of the last five years which include the cloning and sequencing of the cDNAs and genes for corticosteroid binding globulin, testosterone estradiol binding globulin and androgen binding protein, as well as the tissue distribution and regulation of their mRNAs in normal tissues and cancer cell lines.

Androgen-Binding Protein↗
PubMed1976

Hydatid disease of the liver with thoracic involvement.

Eleven patients with hydatid disease of the liver with intrathoracic involvement have been treated at this hospital, and another patient was treated previously elsewhere. The clinical and roentgenologic symptoms depend greatly upon the evolutionary stage of the disease. General conditions are seriously affected in instances of ruptured and infected cysts. When the cysts open into the tracheobronchial tree as a result of coughing up pus in profuse quantities, the general condition may improve to a certain degree, but bronchopulmonary symptoms increase at that moment. An important spitting of bile must alert us to the existence of biliary hypertension. This condition must be treated first to avoid recurrence of the process. According to our experience, surgical treatment is based upon correct drainage of the cystic intrahepatic cavity under the diaphragm, separating the pleural cavity completely from the intrahepatic; excision of the transdiaphragmatic fistulous tract; conservative indications for pulmonary resection, and possible existence of biliary hypertension before and after operation.

Adult↗
PubMedDate not supplied

Analysis of bone alkaline phosphatase as a marker for the diagnosis of osteoporosis in men under androgen ablation.

The objective of this study was to evaluate the usefulness of serum determination of bone alkaline phosphatase (BAP) in the diagnosis of osteoporosis in men with prostate cancer under androgen ablation. Serum levels of BAP and bone mineral density (BMD) were assessed in 110 patients with non-metastatic, treated prostate cancer. Fifty-eight patients were under androgen deprivation during a period between two and 96 months and 52 had been submitted only to radical prostatectomy. Mean serum BAP was 11.8 ng/mL in patients with normal BMD, 16.7 ng/mL in patients with osteopenia (p. 0.058), and 19.3 ng/mL in patients with osteoporosis (p = 0.044). The correlation between serum BAP and BMD was significant (p. 0.006) but with an index of only 0.26. Receiver operating characteristic analysis for the diagnosis of osteoporosis showed an area under the curve of 0.608. None of the cutoff points that provided specificities of 75%, 90% and 95% gave significant distributions. The positive and negative predictive values as well as the odds ratios were not of any clinical usefulness. We conclude that serum BAP should not be considered a good marker for the diagnosis of osteoporosis in men with prostate cancer. Therefore, BAP serum determination cannot replace bone densitometry as a diagnostic tool.

Aged↗
PubMedDate not supplied

Usefulness of prostate-specific antigen nadir as predictor of androgen-independent progression of metastatic prostate cancer.

The objective of this study was to analyze the value of the nadir level of prostate-specific antigen (PSA) to predict androgen-independent progression (AIP) in metastatic prostate cancer patients after androgen deprivation therapy. In a group of 185 metastatic prostate cancer patients who received androgen deprivation therapy serum PSA was determined every three months until AIP occurred. Multiple regression analysis was performed to define independent clinical and PSA-related predictors of AIP. AIP was assumed to be present after two consecutive increases in serum PSA after the PSA nadir. Independent predictors of the duration of AIP-free survival (less than 12 months versus more than 12 months) were the extent of bone involvement (six or fewer hot spots versus more than six) with an odds ratio (O.R.) of 3.95, Gleason score (7 or less versus more than 7) with an O.R. of 3.47, and PSA nadir (2 microg/L or less versus more than 2 microg/L) with an O.R. of 14.63. AIP was independently predicted by the extent of bone involvement with an O.R. of 1.72, Gleason score with an O.R. of 1.74, PSA nadir with an O.R. of 3.22, and time to reach the PSA nadir (9 months or less versus more than 9 months) with an O.R. of 2.84. When patients were stratified according to these predictors, those with three good prognostic factors had a median AIP-free survival of 58 months while those with two, one or no good prognostic factors had a median AIP-free survival of 19 months, 12 months and 7 months, respectively. We conclude that the PSA nadir seems to be a good predictor of AIP in patients with metastatic prostate cancer after androgen deprivation therapy. Time to PSA nadir, extent of bone involvement and Gleason score are also independent predictors. The combination of these prognostic factors allows to stratify metastatic prostate cancer patients for the prediction of AIP.

Adult↗
PubMedDate not supplied

Behavior of free testosterone in patients with prostate cancer on androgen deprivation therapy.

OBJECTIVES: Determination of free testosterone (FT) serum level is an efficient method to evaluate bioavailable testosterone. We analyzed the behavior of serum FT in patients with prostate cancer receiving androgen deprivation therapy (ADT) and correlated FT with total testosterone (TT). We also analyzed the efficiency of both isoforms in the evaluation of the ADT. METHODS: Serum levels of TT and FT were determined in 191 patients with prostate cancer in a cross-sectional study. A subset of 56 patients submitted only to radical prostatectomy served as control group. The remaining 135 patients with advanced prostate cancer on three-month LHRH agonist treatment comprised the study group. The median age of the population was 73 years (range, 53-86 years) and the median time on ADT was 42 months (6-198). RESULTS: A significant correlation and linear regression between TT and FT was observed (r2 0.948). The efficiency of TT and FT to discriminate patients with and without ADT was similar (AUC: 0.993 and 0.995, respectively, p > 0.05). A castration level of serum FT established at 1.7 pg/mL had a sensitivity of 85.9% and a specificity of 100%, which are similar to the sensitivity and specificity of 50 ng/dL of TT. All patients without ADT had levels of serum TT and FT above the castration level. In 19 of the 135 (14.1%) patients on ADT serum TT was above 50 ng/dL. In 12 of these 19 patients (63.2%) serum FT was below 1.7 pg/mL while in seven patients (5.2%) FT was also above the castration level. CONCLUSIONS: The castration level of FT was established at 1.7 pg/mL. Serum TT and TF correlated very well; however, they seemed to provide complementary information in the evaluation of ADT efficiency. 14.1% of the patients on ADT failed to reach the castration level of serum TT; determination of serum FT in these patients would reduce this rate to 5.2%.

Aged↗