Mayo Clinic

About: Mayo Clinic is a healthcare organization based out in Rochester, Minnesota, United States. It is known for research contribution in the topics: Population & Transplantation. The organization has 63387 authors who have published 169578 publications receiving 8114006 citations.

Effect of dutasteride on the risk of prostate cancer.

Abstract: Background We conducted a study to determine whether dutasteride reduces the risk of incident prostate cancer, as detected on biopsy, among men who are at increased risk for the disease. Methods In this 4-year, multicenter, randomized, double-blind, placebo-controlled, parallelgroup study, we compared dutasteride, at a dose of 0.5 mg daily, with placebo. Men were eligible for inclusion in the study if they were 50 to 75 years of age, had a prostate-specific antigen (PSA) level of 2.5 to 10.0 ng per milliliter, and had had one negative prostate biopsy (6 to 12 cores) within 6 months before enrollment. Subjects underwent a 10-core transrectal ultrasound-guided biopsy at 2 and 4 years. Results Among 6729 men who underwent a biopsy or prostate surgery, cancer was detected in 659 of the 3305 men in the dutasteride group, as compared with 858 of the 3424 men in the placebo group, representing a relative risk reduction with dutasteride of 22.8% (95% confidence interval, 15.2 to 29.8) over the 4-year study period (P<0.001). Overall, in years 1 through 4, among the 6706 men who underwent a needle biopsy, there were 220 tumors with a Gleason score of 7 to 10 among 3299 men in the dutasteride group and 233 among 3407 men in the placebo group (P = 0.81). During years 3 and 4, there were 12 tumors with a Gleason score of 8 to 10 in the dutasteride group, as compared with only 1 in the placebo group (P = 0.003). Dutasteride therapy, as compared with placebo, resulted in a reduction in the rate of acute urinary retention (1.6% vs. 6.7%, a 77.3% relative reduction). The incidence of adverse events was similar to that in studies of dutasteride therapy for benign prostatic hyperplasia, except that in our study, as compared with previous studies, the relative incidence of the composite category of cardiac failure was higher in the dutasteride group than in the placebo group (0.7% [30 men] vs. 0.4% [16 men], P = 0.03). Conclusions Over the course of the 4-year study period, dutasteride reduced the risk of incident prostate cancer detected on biopsy and improved the outcomes related to benign prostatic hyperplasia. (ClinicalTrials.gov number, NCT00056407.)

Breast Cancer, Version 3.2020, NCCN Clinical Practice Guidelines in Oncology

Abstract: This selection from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Bladder Cancer focuses on the clinical presentation and workup of suspected bladder cancer, treatment of non-muscle-invasive urothelial bladder cancer, and treatment of metastatic urothelial bladder cancer because important updates have recently been made to these sections. Some important updates include recommendations for optimal treatment of non-muscle-invasive bladder cancer in the event of a bacillus Calmette-Guerin (BCG) shortage and details about biomarker testing for advanced or metastatic disease. The systemic therapy recommendations for second-line or subsequent therapies have also been revised. Treatment and management of muscle-invasive, nonmetastatic disease is covered in the complete version of the NCCN Guidelines for Bladder Cancer available at NCCN.org. Additional topics covered in the complete version include treatment of nonurothelial histologies and recommendations for nonbladder urinary tract cancers such as upper tract urothelial carcinoma, urothelial carcinoma of the prostate, and primary carcinoma of the urethra.

Mutations of the gene encoding the protein kinase A type I-α regulatory subunit in patients with the Carney complex

Abstract: Carney complex (CNC) is a multiple neoplasia syndrome characterized by spotty skin pigmentation, cardiac and other myxomas, endocrine tumours and psammomatous melanotic schwannomas. CNC is inherited as an autosomal dominant trait and the genes responsible have been mapped to 2p16 and 17q22-24 (refs 6, 7). Because of its similarities to the McCune-Albright syndrome and other features, such as paradoxical responses to endocrine signals, genes implicated in cyclic nucleotide-dependent signalling have been considered candidates for causing CNC (ref. 10). In CNC families mapping to 17q, we detected loss of heterozygosity (LOH) in the vicinity of the gene (PRKAR1A) encoding protein kinase A regulatory subunit 1-alpha (RIalpha), including a polymorphic site within its 5' region. We subsequently identified three unrelated kindreds with an identical mutation in the coding region of PRKAR1A. Analysis of additional cases revealed the same mutation in a sporadic case of CNC, and different mutations in three other families, including one with isolated inherited cardiac myxomas. Analysis of PKA activity in CNC tumours demonstrated a decreased basal activity, but an increase in cAMP-stimulated activity compared with non-CNC tumours. We conclude that germline mutations in PRKAR1A, an apparent tumour-suppressor gene, are responsible for the CNC phenotype in a subset of patients with this disease.

Updated Data on Proximal Femur Bone Mineral Levels of US Adults

Abstract: This paper describes data on bone mineral levels in the proximal femur of US adults based on the nationally representative sample examined during both phases of the third National Health and Nutrition Examination Survey (NHANES III, 1988–94), and updates data previously presented from phase 1 only. The data were collected from 14646 men and women aged 20 years and older using dual-energy X-ray absorptiometry, and included bone mineral density (BMD), bone mineral content (BMC) and area of bone scanned in four selected regions of interest (ROI) in the proximal femur: femur neck, trochanter, intertrochanter and total. These variables are provided separately by age and sex for non-Hispanic whites (NHW), non-Hispanic blacks (NHB) and Mexican Americans (MA). NHW in the southern United States had slightly lower BMD levels than NHW in other US regions, but these differences were not sufficiently large to prevent pooling of the data. The updated data provide valuable reference data on femur bone mineral levels of noninstitutionalized adults. The updated data on BMD for the total femur ROI of NHW have been selected as the reference database for femur standardization efforts by the International Committee on Standards in Bone Measurements.

Mechanical and Chemical Unfolding of a Single Protein: A Comparison

Abstract: Is the mechanical unraveling of protein domains by atomic force microscopy (AFM) just a technological feat or a true measurement of their unfolding? By engineering a protein made of tandem repeats of identical Ig modules, we were able to get explicit AFM data on the unfolding rate of a single protein domain that can be accurately extrapolated to zero force. We compare this with chemical unfolding rates for untethered modules extrapolated to 0 M denaturant. The unfolding rates obtained by the two methods are the same. Furthermore, the transition state for unfolding appears at the same position on the folding pathway when assessed by either method. These results indicate that mechanical unfolding of a single protein by AFM does indeed reflect the same event that is observed in traditional unfolding experiments. The way is now open for the extensive use of AFM to measure folding reactions at the single-molecule level. Single-molecule AFM recordings have the added advantage that they define the reaction coordinate and expose rare unfolding events that cannot be observed in the absence of chemical denaturants.