Turbulent urinary flow in the urethra could be a causal factor for benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH) is the most common form of prostate disease in middle-aged and elderly men, and leads to severe impairment later in life. Despite its significant impact on public health, the underlying cause of BPH is yet to be determined. This hypothesis proposes a new causal factor for BPH. Applying concepts of dynamics of fluids to the process of urination it could be stated that a turbulent urinary flow through the passage of the urethra. The turbulent urinary flow in the urethra applies pressure and stretch forces to the surrounding tissue. This stimulus repeated over time and coupled with age-related changes of the urethral tissue could contribute to the development of BPH. In support of this hypothesis, several mechanotransduction studies have shown that vibration and pressure forces applied to different cell tissues can provoke cellular and molecular changes. Another supportive data is the presence of the hyperplasic reaction surrounding the urethra specifically located in the transition zone, the only zone where BPH develops. It is crucial to identify causal factors to understanding the disease and to determine effective primary prevention strategies. Future studies of the dynamics of fluids in the urethra are warranted. The finding of significant forces transmitted to the periurethral tissue from a turbulent urinary flow could give us the clue to the underlying cause of BPH. If this hypothesis proves to be valid there are several primary prevention measures that could be implemented to impede the development of BPH. Educational intervention measures in younger populations to avoid frequent urinary retention and active urination (process of forcing the urine through the urethra at a high velocity) could be considered. Studies of the impact of turbulence in the standing vs. sitting position during urination in men should also be considered.     

Effects of NH4Cl-induced systemic metabolic acidosis on kidney mitochondrial coupling and calcium transport in rats.

BACKGROUND: We have previously shown that chronic metabolic acidosis, induced in rats by NH(4)Cl feeding, leads to nephron hypertrophy and to a decreased water-salt reabsorption by the kidneys. Since mitochondria are the main source of metabolic energy that drives ion transport in kidney tubules, we examined energy-linked functions (respiration, electrochemical membrane potential and coupling between respiration and ADP phosphorylation) in mitochondria isolated from rat kidney and liver at 48 h after metabolic acidosis induced by NH(4)Cl. METHODS: Mitochondria isolated from the kidneys and liver of metabolic acidotic rats, induced by NH(4)Cl, was used to study of the oxygen consumption by Clark-type electrode, mitochondrial electrical transmembrane potential estimated by the safranine O method and the variations in free medium Ca(2+) concentrations examined by absorbance spectrum of Arsenazo III set at the 675-685 nm wavelength pair. RESULTS: Whole kidney and liver mitochondria isolated from 48 h acidotic rats presented higher resting respiration, lower respiratory control and a lower ADP/O ratio than controls. These differences in mitochondrial coupling, between respiration and oxidative phosphorylation (ATP synthesis), were totally corrected when experiments were carried out in the presence of carboxyatractyloside, GDP and BSA, indicating that mitochondrial uncoupling proteins are more active in acidotic rat kidneys. Interestingly, determination of Ca(2+) transport demonstrated a faster rate of initial Ca(2+) uptake by acidotic kidney mitochondria, which resulted in a lower concentration of extra-mitochondrial Ca(2+) under steady-state conditions (Ca(2+) set point) when compared with control mitochondria. In contrast, there were no significant differences in the rates of Na(+) or ruthenium red induced Ca(2+) efflux. CONCLUSIONS: We suggest that the mild uncoupling and higher Ca(2+) accumulation represents an adaptation of the mitochondria to cope with conditions of oxidative stress and high cytosolic Ca(2+), which are associated with a decreased efficiency of oxidative phosphorylation that may explain, at least in part, the striking natriuresis observed under chronic acidosis. Finally, there were no changes in Ca(2+) transport or coupling in liver mitochondria isolated from the acidotic rats.     

Laparoscopic live donor nephrectomy in patients surgically treated for morbid obesity

In the past, morbid obesity was considered a relative contraindication to renal donation; however, more recent publications have shown that laparoscopic renal surgery is safe and effective for obese donor nephrectomy. We report the performance of a bariatric surgery before the kidney donation in 2 patients in order to improve their medical condition and to reduce their surgical risk to the transplantation procedure. After bariatric surgery, both donors lost more than 30% of their initial corporal weight and their donation procedure was successfully performed, with uneventful postoperative courses.     

Enhanced insulin secretion and glucose tolerance in rats exhibiting low plasma free fatty acid levels and hypertriglyceridaemia due to congenital albumin deficiency

Congenitally analbuminaemic individuals and rats (NARs) exhibit several metabolic abnormalities, including hypertriglyceridaemia and plasma free fatty acid deficiency. Our aim was to study glucose homeostasis and insulin secretion in NARs. Plasma concentrations of lipids, glucose and insulin and secretion of insulin from the pancreatic islets were measured in female NARs and control animals (Sprague-Dawley rats; SDRs). Glucose homeostasis tests were also performed. Plasma glucose levels were similar between NARs and SDRs, irrespective of feeding status. However, fed insulinaemia was ～37% higher (P 0.05) in NARs than in SDRs. The NARs displayed a markedly increased glucose tolerance, i.e. the integrated glycaemic response was one-third that of the control animals. Enhanced glucose tolerance was associated with threefold higher insulinaemia at peak glycaemia after a glucose load than in the control animals. Similar peripheral insulin sensitivity was observed between groups. Isolated pancreatic islets from NARs secreted significantly more insulin than islets from SDRs in response to a wide range of glucose concentrations (2.8-33.3 mm). Despite having similar liver glycogen contents in the fully fed state, NARs had ～40% (P 0.05) lower glycogen contents than SDRs after 6 h fasting. The injection of a gluconeogenic substrate, pyruvate, elicited a faster rise in glycaemia in NARs compared with SDRs. Overall, NARs displayed enhanced glucose tolerance, insulin secretion and gluconeogenic flux. The higher glucose tolerance in NARs compared with SDRs is attributed to enhanced islet responsiveness to secretagogues, while peripheral insulin sensitivity seems not to be involved in this alteration. We propose that the enhanced glucose metabolism is a chronic compensatory adaptation to decreased free fatty acid availability in NARs.     

Prevalence of oral anticoagulation in atrial fibrillation

OBJECTIVES:

Atrial fibrillation is the most common sustained arrhythmia and is associated with poor outcomes, including stroke. The ability of anticoagulation therapy to reduce the risk of stroke has been well established; however, the prevalence of anticoagulation therapy use in the Public Health System is unknown. The aim of this study is to evaluate both the prevalence of anticoagulation therapy among patients with atrial fibrillation and the indications for the treatment.

METHODS:

In this cross-sectional study, we included consecutive patients who had atrial fibrillation documented by an electrocardiogram performed between September 2011 and March 2012 at a university hospital of the Public Health System. The variables analyzed included the risk of a thromboembolic event and/or bleeding, the use of antiplatelet or anticoagulation therapy, the location where the electrocardiogram report was initially reviewed and the specialty of the physician who initially reviewed it.

RESULTS:

We included 162 patients (mean age 68.9 years, 56% men). Hypertension (90.1%), heart failure (53.4%) and stroke (38.9%) were the most prevalent diseases found. Only 50.6% of the patients knew that they had atrial fibrillation. Regarding the use of therapy, only 37.6% of patients classified as high risk according to the CHADS2 scores and 35.5% according to the CHA2DS2VASc used oral anticoagulation. A presumptive diagnosis of heart failure and the fact that the electrocardiogram was evaluated by a cardiologist were the only independent predictors of the use of anticoagulants.

CONCLUSIONS:

Our study found a low prevalence of oral anticoagulation therapy among patients with atrial fibrillation and an indication for stroke prophylaxis for the use of this therapy, including among those with high CHADS2 and CHA2DS2VASc scores.     

The combination of mifepristone and misoprostol for the termination of pregnancy

The combination of 200 mg of mifepristone followed by 25 μg to 800 μg (depending on gestational age) of misoprostol has been shown to be effective for the termination of pregnancy throughout gestation. The dose of misoprostol should be reduced as gestational age increases. Mifepristone is not indicated for induction of labor with a live fetus because there are no data to confirm that it does not have a possible deleterious fetal effect. The course of treatment and prerequisites for medical abortion and recommended mifepristone and misoprostol regimens for different gestational ages are described, along with the side effects, management of complications, and postabortion care. The use of the mifepristone-misoprostol combination regimen for induction of labor in cases of fetal death is also described.     

Maternal near miss and maternal death in the World Health Organization��s 2005 global survey on maternal and perinatal health

Objective

To develop an indicator of maternal near miss as a proxy for maternal death and to study its association with maternal factors and perinatal outcomes.

Methods

In a multicenter cross-sectional study, we collected maternal and perinatal data from the hospital records of a sample of women admitted for delivery over a period of two to three months in 120 hospitals located in eight Latin American countries. We followed a stratified multistage cluster random design. We assessed the intra-hospital occurrence of severe maternal morbidity and the latter’s association with maternal characteristics and perinatal outcomes.

Findings

Of the 97 095 women studied, 2964 (34 per 1000) were at higher risk of dying in association with one or more of the following: being admitted to the intensive care unit (ICU), undergoing a hysterectomy, receiving a blood transfusion, suffering a cardiac or renal complication, or having eclampsia. Being older than 35 years, not having a partner, being a primipara or para > 3, and having had a Caesarean section in the previous pregnancy were factors independently associated with the occurrence of severe maternal morbidity. They were also positively associated with an increased occurrence of low and very low birth weight, stillbirth, early neonatal death, admission to the neonatal ICU, a prolonged maternal postpartum hospital stay and Caesarean section.

Conclusion

Women who survive the serious conditions described could be pragmatically considered cases of maternal near miss. Interventions to reduce maternal and perinatal mortality should target women in these high-risk categories.