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Surgical Castration (surgical + castration)
Selected AbstractsIncreased mite parasitism as a cost of testosterone in male striped plateau lizards Sceloporus virgatusFUNCTIONAL ECOLOGY, Issue 2 2007ROBERT M. COX Summary 1Testosterone (T) co-ordinates the seasonal and sex-specific expression of numerous physiological, behavioural and morphological traits that contribute to male reproductive success. However, increased susceptibility to parasitism has been proposed as a potential cost of elevated plasma T. 2During the spring breeding season, male striped plateau lizards Sceloporus virgatus harbour significantly more ectoparasitic mite larvae (Acari: Trombiculidae) than females. Plasma T levels are also elevated in males at this time, suggesting that sex differences in mite parasitism may be driven by underlying sex differences in circulating T. 3We tested this hypothesis experimentally by manipulating plasma T levels of yearling males via surgical castration and exogenous T implants. Upon recapture of free-living animals, we found significantly fewer mites on castrated males relative to either intact controls or castrated males that received T implants. 4After removing variance attributable to treatment effects, we observed (1) a positive correlation between residual measures of plasma T and mite load, and (2) a negative correlation between residual measures of mite load and growth rate. These correlations suggest a growth cost associated with mite parasitism. 5Previous studies have shown that exogenous T increases parasitism, but ours is one of the few to show that castration also reduces parasitism. This result, coupled with the fact that our induced plasma T levels remain within physiological limits, makes this one of the clearest demonstrations of a functional relationship between T and parasitism in any free-living vertebrate. [source] Hormone escape is associated with genomic instability in a human prostate cancer modelINTERNATIONAL JOURNAL OF CANCER, Issue 5 2009Marie-Emmanuelle Legrier Abstract Lack of hormone dependency in prostate cancers is an irreversible event that occurs through generation of genomic instability induced by androgen deprivation. Indeed, the cytogenetic profile of hormone-dependent (HD) prostate cancer remains stable as long as it received a hormone supply, whereas the profile of hormone-independent (HID) variants acquired new and various alterations. This is demonstrated here using a HD xenografted model of a human prostate cancer, PAC120, transplanted for 11 years into male nude mice and 4 HID variants obtained by surgical castration. Cytogenetic analysis, done by karyotype, FISH, CGH and array-CGH, shows that PAC120 at early passage presents numerous chromosomal alterations. Very few additional alterations were found between the 5th and 47th passages, indicating the stability of the parental tumor. HID variants largely maintained the core of chromosomal alterations of PAC120 , losses at 6q, 7p, 12q, 15q and 17q sites. However, each HID variant displayed a number of new alterations, almost all being specific to each variant and very few shared by all. None of the HID had androgen receptor mutations. Our study indicates that hormone castration is responsible for genomic instability generating new cytogenetic abnormalities susceptible to alter the properties of cancer cell associated with tumor progression, such as increased cell survival and ability to metastasize. © 2008 Wiley-Liss, Inc. [source] Clinical experience of hormone therapy to bone metastatic prostate cancerINTERNATIONAL JOURNAL OF UROLOGY, Issue 5 2006MASAMI WAKISAKA Background:, A novel hormone therapy was instituted against prostate cancer with bone metastases and its therapeutic efficacy was investigated. Methods:, A total of 35 patients who had been pathologically diagnosed with carcinoma of the prostate between January 1994 and December 2003 were entered into the present study. Patients aged over 80 years were excluded from the study. As for the treatment methodology, diethylstilbestrol diphosphate (DES-P) at 500 mg/day was intravenously injected for 20,40 days, followed by monotherapy with an analog of luteinizing hormone-releasing hormone (LHRH). In all subjects, surgical castration was not conducted. The survival rate was analysed according to the method of Kaplan,Meier. Results:, One of the 35 patients was excluded from the study as this patient did not meet the inclusion criteria. There were four patients who dropped out of the study. On histology, 17 patients had moderately differentiated adenocarcinomas and 17 patients had poorly differentiated adenocarcinomas. As for the extent of disease (EOD), the patients were classified as with a score of 1 in 10 patients, 2 in 13 patients, 3 in 7 patients and 4 in 4 patients. The 5-year progression-free survival rate and overall survival rate were 24.3% and 60.6%, respectively. Conclusion:, Our new hormone therapy in the management of prostate cancer metastatic to the bone has demonstrated markedly superior therapeutic results compared to those so far obtained. [source] Comparison of microvessel densities in rat prostate tissues treated with finasteride, bicalutamide and surgical castration: A preliminary studyINTERNATIONAL JOURNAL OF UROLOGY, Issue 2 2005CEVDET KAYA Abstract Background: A group of anti-androgens with different mechanisms of action and adverse effects have been investigated in patients with gross hematuria related to benign prostate hyperplasia; however, there is not yet any consensus about the standard management of these patients. The present study aims to identify if any one type of the hormonal intervention is superior in terms of the suppression of microvessel formation in the prostate. Materials and methods: A total of 28 mature, healthy male Sprague,Dawley rats (300 ± 50 g) were used in this study. The rats were randomly assigned to one of four groups (n = 7 per group). The effects of three different hormonal therapies on angiogenesis and microvascularity in rat ventral prostate were compared. Groups 1 and 2 were treated for 28 days with finasteride and bicalutamide, respectively, and rats from Group 3 underwent surgical castration. Following treatment, all rats included in the study underwent dissection of the ventral prostate and immunohistochemical analysis of microvessel density by factor VIII-related antigen. Results: The mean number of microvessels in the finasteride and bicalutamide groups was 24.5 (±8.44 SE) and 27 (±9.89 SE) respectively. In contrast, the castration and control groups had microvessel numbers of 12.9 (±5.35 SE) and 40.3 (±5.03 SE) respectively. Differences were statistically significant between all three treatment groups and the controls (P < 0.005); the number of microvessels in rat prostate tissues of the control group was significantly higher than the treatment groups. Mean microvessel densities in the bicalutamide and finasteride groups were significantly higher than microvessel densities in the castration group (P < 0.005). There was no statistically significant difference between mean microvessel number in rat prostate tissue treated with finasteride or bicalutamide (P > 0.05). Conclusions: Even though finasteride was not as effective as castration in reducing microvessel number, its effect was equal to that of bicalutamide in terms of suppressing the angiogenesis in prostatic tissue. Based on the findings of the present study, finasteride might offer a viable option in the management of macroscopic hematuria by inhibition of microvessel formation within the prostatic tissue. Further clinical studies are warranted. [source] Replacement of surgical castration by GnRH inhibition for rat prostate androgen receptor preparationsJOURNAL OF APPLIED TOXICOLOGY, Issue 5 2001J. Ashby No abstract is available for this article. [source] On the invisibility of the emasculated (Respond to this article at http://www.therai.org.uk/at/debate)ANTHROPOLOGY TODAY, Issue 1 2010Richard Wassersug Castrating a male by destroying his testicles is a practice that most people assume ended a century or so ago with the collapse of the Chinese and Ottoman Empires and the death of the last castrato in the Vatican choir. However, because advanced prostate cancer is treated by either chemical or surgical castration, there are probably more castrated men alive today than ever before in history. Castration is also used in the western world as either a step in the sexual reassignment of male to female (MtF) transsexuals or rarely to treat recidivist sexual predators. In addition, some men desire emasculation who are neither cancer patients, MtF transsexuals, nor sexual predators. In this essay I argue that the public association of castration with sexual predators and deviant behaviour is so great that men, who require it as a medical treatment for cancer or who seek it for other reasons typically hide from public view. One consequence of the shame associated with castration is that those, who desire emasculation but do not have a diagnosis of cancer, too often subject themselves to risky and illegal amateur surgeries outside the medical system. I argue that for whatever reason a male seeks castration, the overall invisibility of the emasculated in modern society is a disservice. It minimizes the public's understanding of the magnitude of the impact of castration on cancer patients and it inhibits those in need of medical treatment from getting it in an appropriate and timely fashion. [source] | ||||||||||