Effects of acute brainstem compression on auditory brainstem response in the guinea pig

BACKGROUND: The purpose of this study was to establish the norm for parameters of auditory brainstem response (ABR) in the guinea pig and to investigate if acute brainstem compression results in significant changes to these parameters. METHODS: Thirty-six guinea pigs with positive Preyer's reflex were anesthetized. A craniectomy was performed to remove the right occipital bone and the dura mater was opened to expose the brain, cerebellum and cerebellopontine angle (CPA). A small inflatable balloon was placed into the CPA precisely and slowly. ABR was recorded before incision of the skin as a baseline value, after placement and after inflation of the balloon with water at 0.1-ml intervals. RESULTS: Five stable peaks were recorded in 27 experimental animals. When the balloon was inflated with 0.1 ml water, the absolute latency (AL) of peaks IV and V and the interpeak latency (IPL) of peaks III and IV, and IV and V were prolonged. The amplitude ratios (AR) of peaks II, III, IV and V to peak I decreased. Inflation of the balloon with 0.2 ml of water caused further elongation of ALs of peaks IV and V and decreases in each AR. When the balloon volume increased to 0.3 ml, peak V became unrecognizable and peaks III and IV showed significant elongation of AL; peaks I and II did not show significant change in ALs. Further increase of the balloon volume to 0.4 ml resulted in disappearance of peaks III, IV and V; AL of peak II was also elongated. However, the amplitude and AL of peak I remained unchanged. Similar changes were observed in IPLs. CONCLUSIONS: This study establishes the norm of parameters of ABR in guinea pigs and demonstrates that acute brainstem compression causes elongation of ALs and IPLs of peaks II, III, IV and V. This suggests that peaks II, III, IV and V come from the brainstem and that peak I is not generated from the brainstem in the guinea pig.     

Recommendations for handling of pediatric liver biopsy specimens

The coronary endothelium plays a central role in the modulation of coronary vascular tone via the production and release of vasoactive mediators. A number of cardiovascular disease states are associated with coronary endothelial dysfunction, which results in an imbalance between vasoactive substances. Endothelin is a potent vasoconstrictor produced by the coronary endothelium and has been implicated in the pathogenesis of coronary endothelial dysfunction. This review examines the relationship between endothelin and coronary endothelial dysfunction as it occurs in a number of cardiovascular disease states and explores potential therapeutic options.     

WHOLE SOYBEANS AS A MEANS OF INCREASING PROTEIN AND CALORIES IN MAIZE-BASED DIETS

Studies have indicated that one factor responsible for protein-calorie malnutrition in children is the deficiency of good-quality protein and calories in their habitual diets. Previous investigations attempted to solve the problem by means of supplementation with good-quality protein, but this research has not considered direct correction of the calorie deficit. Thus studies were carried out to improve both the protein quality and calorie content with a single food: soybean, added and processed together with maize. Two types of food preparations were studied: tortillas made from 85% maize and 15% whole soybeans (processed together by the lime-cooking treatment used for maize) which when compared to the usual one, had a higher protein and calorie content, and was very acceptable in both appearance and taste. Higher levels of soybean mixed with maize were also tested to develop food preparations with higher concentrations of both calories and protein. These were also processed by the lime-cooking treatment. From these tests a mixture of soybean and maize in the proportion 28g soybean to 72g maize gave a food preparation with 18% protein, 10% fat and a high-protein quality as measured by its PER. The use of higher soybean levels did not improve protein quality, and the yields of the resultant products decreased.     

Mechanisms for oliguria in acute renal failure

Equations previously developed to describe the enterohepatic circulation of the major biliary bile acids in man (Gastroenterology 67:887, 1974) were modified in order to predict the effect on biliary bile acid composition and pattern of amino acid conjugation after prototypic perturbations of the enterohepatic circulation in man. For the steroid moiety, the effects of bile acid feeding, increased recycling frequency, decreased intestinal conservation, and increased dehydroxylation were simulated. For the glycine or taurine moiety, the effect of increased deconjugation or preferential loss of one of the amino acid moieties was simulated. For the steroid moiety, the steady state biliary bile acid composition reflects the balance between input and conservation for each bile acid. Similarly, the distribution of bile acids between glycine and taurine conjugates reflects the balance between conjugation and conservation for each amino acid moiety. Because these values may vary widely and independently, analysis of biliary bile acid composition in terms of the steroid moiety or the glycine-taurine ratio per se cannot be used to infer the relative rates of input or conjugation.     

Generalized equations for predicting body density of women

Previous research with women has shown that body composition regression equations derived from anthropometric variables were population specific. This study sought to derive generalized equations for women differing in age and body composition. The hydrostatic method was used to determine body density (BD) and percent fat (%F) on 249 women in 18 to 55 years (X = 31.4 +/- 10.8 yrs) and 4 to 44 %F (X = 24.1 +/-7.2 %F). Skinfold fat (S), gluteal circumference (C) and age were independent variables. The quadratic form of the sum of three, four and seven S in combination with age and gluteal C produced multiple correlations that ranged from 0.842 to 0.867 with standard errors of 3.6 to 3.8 %F. The equations were cross-validated on a different sample of 82 women with similar age and %F characteristics. The correlations between predicted and hydrostatically determined %F ranged from 0.815 to 0.820 with standard errors of 3.7 to 4.0 %F. This study showed that valid generalized body composition equations could be derived for women varying in age and body composition, but care need to be exercised with women over an age of forty.     

Brugia malayi in a cervical smear

A microfilaria, identified as that of Brugia malayi, was found in a routine cervical smear from a healthy, 38-year-old female Malaysian aborigine.     

Operations in concomitant diseases of the abdominal organs

Under consideration are one-moment operations for associated lesions of abdominal organs. Based on the experience with 103 such operations, the authors subdivided patients into two groups: emergency operated patients and those in whom planned interventions were performed. It is believed by the authors, that a careful clinical preoperative examination of the latter and methodical revision of abdominal organs in urgent laparotomies make it possible to reveal an associated pathology of abdominal organs and to perform a radical one-moment operative procedure.