Rabbit esophageal cells possess an Na+,H+ antiport

The development of esophagitis is the result of hydrogen ion diffusion into the mucosa leading to cellular acidification and necrosis. In these studies, whether esophageal cells possess transport system(s) that can respond to cytoplasmic acidification was assessed; specifically, whether esophageal cells possess an Na+,H+ antiport was determined. Nucleated esophageal cells were isolated from rabbit esophagi using a trypsin-digestion technique that yielded 5-8 x 10(6) cells per esophagus, of which 74% +/- 3% were basal and 26% +/- 8% were squamous. Trypan blue was excluded by 95% +/- 2% of the cells. Cytoplasmic pH (pHi) was measured using the pH-sensitive fluorescence dye 2',7'-bis(2-carboxyethyl)-5 (and -6) carboxyfluorescein acetoxymethyl ester. Cells were acidified to the desired pHi by suspension in solutions with varying external pH (pHo) in the presence of nigericin. When cells acidified to pHi 6.3 were suspended in a choline chloride solution (pHo 7.4), cytoplasmic pHi did not increase. In contrast, Nao+ caused a concentration-dependent increase in the rate of cytoplasmic alkalinization with saturation occurring above 50 mmol/L Nao+. The transporter behaved according to first-order Michaelis-Menten type kinetics with respect to external Na+ and had an apparent Km for Nao+ of 38.4 mmol/L. In contrast, the transporter behaved with greater than first-order kinetics with respect to external Na+ and had an apparent Km for Nao+ of 38.4 mmol/L. In contrast, the transporter behaved with greater than first-order kinetics with respect to cytoplasmic hydrogen ion concentration. Amiloride (10(-4) mol/L) caused a reversible inhibition of Na(+)-dependent alkalinization. Amiloride-sensitive cytoplasmic alkalinization was not observed when either cholineo or Ko+ was substituted for Nao+, while Lio+ resulted in alkalinization that was 60% +/- 8% of that seen with equimolar concentrations of Nao+. The basal pHi of cells suspended in a bicarbonate-free 130 mmol/L NaCl solution (pHo 7.4) averaged 7.42 +/- 0.03 (n = 10); amiloride (10(-4) mmol/L caused the basal pHi to decrease to 7.26 +/- 0.05 (n = 10; P less than 0.0025). When cells were suspended in a choline chloride (pHo 7.4) solution, pHi averaged 7.29 +/- 0.06 (n = 10) (P less than 0.0025 compared with Nao+). These studies indicate that nucleated esophageal cells obtained from rabbits possess an amiloride-sensitive Na+,H+ antiport that functions to regulate basal pHi and responds to intracellular acidification.     

Epidemiology of football injuries in Asia: A prospective study in Qatar

ObjectivesTo investigate the incidence, characteristics and patterns of football injuries at club level in Qatar.DesignProspective cohort study.MethodsData were prospectively collected from the first division football league clubs in Qatar, in accordance with the international consensus statement on football injury epidemiology. An injury was defined as any physical complaint sustained during football activity resulting in the inability to participate fully in the next training or match. Individual injuries and exposure of each player were recorded by the medical staff of each team over one season.ResultsA total of 217 injuries were recorded, with an injury rate during matches of 14.5/1000 h (95% CI: 11.6–18.0) compared with 4.4/1000 h during training sessions (95% CI: 3.7–5.2). More than one third of all injuries were muscle strains (36.4%). Hamstring strains (54.4% of all muscle strains) exhibited a higher incidence than all other injury types (p < 0.001). The thigh was the most frequent injury location (41.9%, p < 0.001). Reinjuries (15% of total injuries) were mainly comprised of muscle strains associated with a higher severity compared with new injuries.ConclusionsDespite the different environmental, social and cultural setting, our findings are comparable with previous data from European club football, confirming the previous finding at national team level that there are no regional peculiarities of football injuries in this part of the Asiatic continent.The relatively high overuse injury incidence rate and the high recurrence rate for (severe) thigh muscle strains, especially during games, warrants prevention strategies.     

Small bowel transplantation

Many patients die each year lacking only a functional small bowel to survive. The minimum amount of small intestinal absorptive surface required to sustain life varies from patient to patient. Prolonged survival with oral alimentation alone has been reported in a few patients with an intact duodenum and as little as 15-45 cm of residual jejunum. However, without long-term total parenteral nutrition (TPN), prolonged patient survival is the exception rather than the rule. Chronic parenteral nutrition is associated with complications, including sepsis, venous thrombosis, metabolic disorders and liver dysfunction. From studies of patients currently on long-term TPN, it would appear that there are between two and three patients per million of population per year who develop irreversible small bowel failure. It is estimated that 20 new patients/year in the UK receiving home TPN would be potential candidates for small bowel transplantation.     

Prognosis of patients with acute renal failure requiring dialysis: results of a multicenter study

Despite several decades of clinical experience, the mortality rate for patients with acute renal failure (ARF) requiring dialysis remains high, and the evaluation of the patients prognosis has been difficult. To date, the Acute Physiology and Chronic Health Evaluation II (APACHE II) scoring system has been used more frequently for prediction in studies of ARF than any other scoring system, but has not been prospectively validated in controlled multicenter studies of this entity. In a multicenter, prospective, controlled trial evaluating the use of biocompatible hemodialysis membranes (BCMs) in patients with ARF, we evaluated the extent to which the APACHE II scoring system, based on the physiological variables in the 24 hours before the onset of dialysis and the presence or absence of oliguria, is predictive of outcome. Analysis of survival and recovery of renal function for the 153 patients treated in this study show that APACHE II scores are predictive both of survival and recovery of renal function, whether analyzed separately by type of dialysis membrane used (BCM or bioincompatible [BICM]) or for both groups combined (all P < 0.01). There was no evidence of a significant center effect or interaction of APACHE II score with dialysis membrane in our study. After adjusting for the APACHE II score, there was a positive effect of the BCM on both probability of survival (P < 0.05) and recovery of renal function (P < 0.01). In patients dialyzed with BCMs, oliguria at onset of dialysis had an adverse effect on both survival and recovery of renal function (both P < 0.01). Receiver operator curves (ROCs) using APACHE II score and the use of BCMs in nonoliguric patients yielded a statistically significant improvement versus the use of APACHE II score alone in the area under the curve (AUC) for survival (0.747 to 0.801; P < 0.05) and recovery of renal function (0.712 to 0.775; P < 0.05). We conclude that the use of the APACHE II score determined at the time of initiation of dialysis for patients with ARF is a statistically significant predictor of patient survival and recovery of renal function. The use of the APACHE II score measured at the time of dialysis initiation, especially when modified by the presence or absence of oliguria, should help in predicting outcome when evaluating interventions for patients with ARF.     

Cerebellar abscesses secondary to occipital dermoid cyst with dermal sinus: case report

BACKGROUND: Hydrocephalus and cerebellar abscesses as the principal manifestations of posterior fossa dermoid cyst are rare. In addition, extradural dermoid cyst of the posterior fossa has been described in only 9 cases in the literature. We present an unusual case of obstructive hydrocephalus due to cerebellar abscesses induced by an adjacent extradural dermoid cyst with complete occipital dermal sinus. CASE DESCRIPTION: A 14-month-old child presented with acute raised intracranially pressure, seizures, and meningitis. Neuroradiological studies revealed cerebellar cysts with ring enhancement associated with a contiguous occipital cyst, with compression of the adjacent cisterns and the fourth ventricle causing hydrocephalus. The diagnosis of cerebellar abscesses with congenital occipital defect was briefly entertained. The patient was treated by radical excision of the occipital cyst with hair contents, the dermal sinus, and the abscesses through a suboccipital approach, followed by systemic antibiotic therapy with a good outcome. Pathologic examination revealed a dermoid cyst. CONCLUSION: Posterior fossa dermoid cyst should be considered in all children with occipital skin lesions, especially dermal sinus. CT scan and MRI are the methods of choice for further investigation of suspect congenital dermal lesions. Neurosurgical treatment of these malformations should be planned early to prevent the high incidence of infections such as bacterial meningitis and cerebellar abscess. Clinical presentation, diagnostic evaluation, and treatment of these rare lesions are reviewed.     

Human scalp recorded sigma activity is modulated by slow EEG oscillations during deep sleep

The EEG during deep sleep exhibits a distinct cortically generated slow oscillation of around and below 1 Hz which can be distinguished from other delta (0.5-3.5 Hz) activity. Intracranial studies showed that this slow oscillation triggers and groups cortical network firing. In the present study, we examined whether the phases of the slow oscillation during sleep stage 4 are correlated with the magnitude of sigma (12-16 Hz) and gamma (> 20 Hz) scalp activity. For this purpose, 10-min segments of uninterrupted stage 4 sleep EEG from 9 subjects were analyzed by applying wavelet techniques. We found that scalp recorded sigma, but not gamma, activity is modulated by the phases of the slow oscillation during deep sleep. Enhancement of sigma activity was observed to be triggered by the peak of the surface positive slow wave component, whereas reduction of sigma activity started around the peak of the negative component.