Effect of normobaric hypoxia on the testis in a murine model

High‐altitude hypoxia generates spermiogram impairment due to germinal epithelium, Leydig cells, sperm and seminal plasma alterations, but precise mechanisms involved are unknown. The objective of this work was to analyse the effect of normobaric hypoxia on the morphology of testicular interstitium and some associated molecular and hormonal factors. Twenty‐four mice were exposed to normobaric hypoxia (8.1% inspired oxygen fraction) during 20 days. The effects on body weight, testicular weight, vascularisation, testosterone, HIF1‐α and VEGF were analysed at different periods of exposure and compared to controls. Hypoxic mice had lower body weight than mice kept in normoxia. Testicular weight raised significantly the 1st day, but remained normal during the rest of experiment. Number of blood vessels per field and mean diameter of vessels were higher in hypoxic mice. Plasmatic and testicular testosterone raised during first 24 h of hypoxia, but decreased on the 5th day. Vascular/interstitial ratio (proportion of interstice occupied by blood vessels) duplicated at the end of the experiment. Most substantial early effects of hypoxia were testicular oedema, increase in number and diameter of blood vessels and elevation of plasmatic and testicular testosterone. Normobaric hypoxia generates similar effects to those induced by hypobaric hypoxia.     

Phagocytic NADPH oxidase overactivity underlies oxidative stress in metabolic syndrome

Oxidative stress plays a critical role in the pathogenesis of atherosclerosis in patients with metabolic syndrome. This study aimed to investigate whether a relationship exists between phagocytic NADPH oxidase activity and oxidative stress and atherosclerosis in metabolic syndrome patients. The study was performed in 56 metabolic syndrome patients (metabolic syndrome group), 99 patients with one or two cardiovascular risk factors (cardiovascular risk factor group), and 28 healthy subjects (control group). NADPH oxidase expression and activity was augmented (P < 0.05) in metabolic syndrome compared with cardiovascular risk factor and control groups. Insulin was enhanced (P < 0.05) in metabolic syndrome patients compared with cardiovascular risk factor and control groups and correlated with NADPH oxidase activity in the overall population. Insulin stimulated NADPH oxidase activity; this effect was abolished by a specific protein kinase C inhibitor. Oxidized LDL and nitrotyrosine levels and carotid intima-media thickness were increased (P < 0.05) in the metabolic syndrome group compared with cardiovascular risk factor and control groups and correlated with NADPH oxidase activity in the overall population. These findings suggest that phagocytic NADPH oxidase overactivity is involved in oxidative stress and atherosclerosis in metabolic syndrome patients. Our findings also suggest that hyperinsulinemia may contribute to oxidative stress in metabolic syndrome patients through activation of NADPH oxidase.     

Number needed to treat: a useful new method of assessing the magnitude of treatment effect and its application to the management of diabetic retinopathy.

The magnitude of treatment effect from randomized controlled trials can be measured in various ways. The number needed to treat is a recently described measure that has been shown to offer several advantages in the clinical interpretation and application of reported treatment effects. It quantifies the number of patents that must be treated in order to prevent one patient from developing the specified outcome. The methods necessary to calculate traditional measures of treatment effect, as well as the number needed to treat, are outlined using the management of diabetic retinopathy as an example. The uses and limitations of the number needed to treat are also discussed.     

Digital imaging of the chest

During the past several years, image acquisition in nuclear medicine, computed tomography, ultrasonography, subtraction angiography, and magnetic resonance has been by digitization. Despite these advances, research in the development of digital imaging in conventional radiography has lagged behind. Although studies with a variety of digital techniques have been carried out on several fronts, we still do not possess a method that has captured the imagination of the majority of radiologists and other physicians to a point where it could replace conventional screen-film imaging. This article reviews the current status and general principles of the technology, focusing on the four digital radiographic techniques that have shown the greatest promise - film digitization, an image intensifier - based system, photostimulable phosphor plates, and a scanned projection system. The physical aspects of each of the four systems and the clinical results that have been reported to date, as well as the advantages and disadvantages of each system, are presented.     

Efficacy of rituximab in an aggressive form of multicentric Castleman disease associated with immune phenomena

Multicentric Castleman disease (MCD) is an uncommon lymphoproliferative disorder for which the best therapeutic option is not yet well established. Immune-related disorders are rare complications of MCD. We report on an MCD case in a 23-year-old patient with extensive abdominal involvement and associated immune hemolytic anemia and Raynaud phenomenon. He was negative for human immunodeficiency virus (HIV) and human herpesvirus-8 (HHV-8). After 8 courses of the anti-CD20 monoclonal antibody (rituximab), the patient achieved complete remission. Interestingly, Raynaud phenomenon disappeared under treatment and no new hemolytic events occurred. Anti-CD20 antibody treatment could be an attractive therapeutic approach for MCD, mainly when immune-related disorders are associated.     

Urinary tract infection due to Corynebacterium urealyticum in kidney transplant recipients: an underdiagnosed etiology for obstructive uropathy and graft dysfunction-results of a prospective cohort study.

BACKGROUND: Corynebacterium urealyticum is a cause of urinary tract infection and encrusting cystitis or pyelitis. Information about this infection in renal transplant recipients is based on case reports. We communicate the first prospective epidemiological study for this population. METHODS: We selected a cohort of 163 renal transplant recipients who were screened for urinary tract infection due to C. urealyticum. Long-term incubation and special media were used for culture of C. urealyticum. The cohort was observed for a mean of 26.2 months (standard deviation, 8.7; range, 1-36 months). Risk factors and outcomes were assessed. RESULTS: At baseline, 16 (9.8%) of 163 patients had C. urealyticum bacteriuria (6 were asymptomatic, 9 had acute cystitis, and 1 had encrusting pyelitis). Independent risk factors (assessed by multivariate analysis) for urinary tract C. urealyticum infection were: antibiotic administration during the previous month (odds ratio, 8.04; 95% confidence interval, 1.57-41.06; P = .012), history of nephrostomy (odds ratio, 51.59; 95% confidence interval, 3.62-736.06; P = .004), and skin colonization (odds ratio, 208.35; 95% confidence interval, 21.54-2015.22; P< .001). Presence of urinary tract infection symptoms for >1 month (odds ratio, 27.7; 95% confidence interval, 2.55-300.5; P = .006) and obstructive uropathy (odds ratio 25.9; 95% confidence interval, 4.43-152.31; P < .001) were more frequent during follow-up in patients with C. urealyticum bacteriuria. CONCLUSIONS: When specifically tested for, C. urealyticum bacteriuria is more prevalent than previously thought in renal transplant recipients, and it is closely related to obstructive uropathy. Future studies are necessary to establish the relevance of treating the infection during follow-up after renal transplantation.