Effects of long-term administration of androgens and estrogen on rhesus monkey prostate: possible induction of benign prostatic hyperplasia

Rhesus monkeys were used to investigate the role of androgenic steroids and estradiol in the induction of hyperplastic changes in stromal and glandular prostate tissues. Adult male rhesus monkeys were procured from the wild and, after routine quarantine procedures, were randomly divided into 5 groups of 5 animals each. Gluteus maximus muscles were injected with 2.5 mg of androstenedione (Group II), 2.5 mg of dihydrotestosterone (DHT) or 0.25 mg of estradiol (Group II), 2.5 mg androstanediol (Diol; Group IV), or Diol in combination with 0.25 mg of estradiol (Group V). Group I consisted of untreated controls. Animals were injected with steroids 3 times a week for 2 years. Treatment with androstenedione (Group II) resulted in stromal hyperplasia in the caudal lobe and an increase in epithelial cell height in all zones except in the central zone of the caudal lobe. In monkeys treated with DHT and estradiol (Group III), stromal hyperplasia in both lobes, a decrease in tubular size, and degranulation and vacuolation of epithelial cells were noticed. Injection of Diol alone (Group IV) or in combination with estradiol (Group V) resulted in a widening of stroma in the central and peripheral zones of cranial and caudal lobes, whereas the tubular size decreased. Diol also induced epithelial cell hypercellularity in the central and peripheral zones of the caudal lobe and in the peripheral zone of the cranial lobe. Prostate-specific antigen levels in Group IV animals gradually increased from 6 months of treatment and were maximal after 18 months of injections. Serum estradiol levels increased to detectable levels in all groups except Group IV. Serum testosterone levels decreased to very low or undetectable levels in all groups, whereas prostate-specific acid phosphatase increased in all treated groups. Prolactin levels were elevated in all treated groups except in animals injected with androstenedione. These results indicate that repeated long-term injections of androstenedione or DHT and estradiol induced stromal hyperplasia, which may be an estrogen-related effect. Androstanediol-induced hypercellularity and stratification of glandular epithelium is comparable to human prostatic intraepithelial neoplasia. These results also suggest that the rhesus monkey is a suitable animal model for experimental induction of prostate diseases.     

Novel Risk Factors for Progression of Diabetic and Nondiabetic CKD: Findings From the Chronic Renal Insufficiency Cohort (CRIC) Study

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Cause-Specific Deaths in Non–Dialysis-Dependent CKD

CKD is associated with higher risk of death, but details regarding differences in cause-specific death in CKD are unclear. We examined the leading causes of death among a non–dialysis-dependent CKD population using an electronic medical record-based CKD registry in a large healthcare system and the Ohio Department of Health mortality files. We included 33,478 white and 5042 black patients with CKD who resided in Ohio between January 2005 and September 2009 and had two measurements of eGFR<60 ml/min per 1.73 m² obtained 90 days apart. Causes of death (before ESRD) were classified into cardiovascular, malignancy, and non-cardiovascular/non-malignancy diseases and non–disease-related causes. During a median follow-up of 2.3 years, 6661 of 38,520 patients (17%) with CKD died. Cardiovascular diseases (34.7%) and malignant neoplasms (31.8%) were the leading causes of death, with malignancy-related deaths more common among those with earlier stages of kidney disease. After adjusting for covariates, each 5 ml/min per 1.73 m² decline in eGFR was associated with higher risk of death due to cardiovascular disease (hazard ratio [HR], 1.10; 95% confidence interval [95% CI], 1.08 to 1.12) and non-cardiovascular/non-malignancy diseases (HR, 1.12; 95% CI, 1.09 to 1.14) but not to malignancy. In the adjusted models, blacks had overall-mortality hazard ratios similar to those of whites but higher hazard ratios for cardiovascular deaths. Further studies to confirm these findings and explain the mechanisms for differences are warranted. In addition to lowering cardiovascular burden in CKD, efforts to target known risk factors for cancer at the population level are needed.     

Advanced therapeutic endoscopist and inflammatory bowel disease: Dawn of a new role

Endoscopy plays a key role in the diagnosis and treatment of patients with inflammatory bowel disease(IBD).Colonoscopy has been traditionally used in the diagnosis of IBD and helps in determination of an important end point in patient management,"mucosal healing".However,the involvement of an advanced endoscopist has expanded with innovations in therapeutic and newer imaging techniques.Endoscopists are increasingly being involved in the management of anastomotic and small bowel strictures in these patients.The advent of balloon enteroscopy has helped us access areas not deemed possible in the past for dilations.An advanced endoscopist also plays an integral part in managing ileal pouchanal anastomosis complications including management of pouch strictures and sinuses.The use of rectal endoscopic ultrasound has been expanded for imaging of perianal fistulae in patients with Crohn’s disease and appears much more sensitive than magnetic resonance imaging and exam under anesthesia.Advanced endoscopists also play an integral part in detection of dyspla-sia by employing advanced imaging techniques.In fact the paradigm for neoplasia surveillance in IBD is rapidly evolving with advancements in endoscopic imaging technology with pancolonic chromoendoscopy becoming the main imaging modality for neoplasia surveillance in IBD patients in most institutions.Advanced endoscopists are also called upon to diagnose primary sclerosing cholangitis(PSC)and also offer options for endoscopic management of strictures through endoscopic retrograde cholangiopancreatography(ERCP).In addition,PSC patients are at increased risk of developing cholangiocarcinoma with a 20%lifetime risk.Brush cytology obtained during ERCP and use of fluorescence in situ hybridization which assesses the presence of chromosomal aneuploidy(abnormality in chromosome number)are established initial diagnostic techniques in the investigation of patients with biliary strictures.Thus advanced endoscopists play an integral part in the management of IBD patients and our article aims to summarize the current evidence which supports this role and calls for developing and training a new breed of interventionalists who specialize in the management of IBD patients and complications specific to those patients.