Technical advances in the Senning operation

Since March 1978, 59 patients with transposition of the great arteries (TGA) ranging in age from 2 months to 6 years have undergone the Senning operation. Forty-six patients (77.9%) had transposition with intact ventricular septum, 8 of them with patent ductus arteriosus; 8 patients (13.5%) had TGA with ventricular septal defect (VSD), 3 of them with previously performed banding; 4 patients (6.7%) had TGA with VSD and pulmonary stenosis (PS), and one (1.6%) had TGA with PS. Prior to correction, 38 cases had undergone a Rashkind septotomy and 15 had had a previous Blalock-Hanlon septectomy. During this time we have introduced some technical modifications of the original Senning operation: (A) right atrial incision, (B) large left atrial wall window, (C) infrasinal suture of the left atrial flap, (D) avoidance of damage to the hypothetical anterior atrioventricular conduction bundle, and recently, in 12 patients, we have used (E) an inverted left atrial appendage as an interatrial flap. There were 9 hospital deaths (15.2%) caused by low cardiac output (4 cases), severe hypoxemia and low cardiac output (4 cases) and one patient with pulmonary venous drainage obstruction died following reoperation. Two patients developed neurological complications that disappeared without sequela. Another complication was a right chylothorax (4 patients), which improved without the necessity of surgical repair. Eighteen patients developed a junctional rhythm for a period over 24 hours. We think that the technical modifications which we present here, partially contribute to improving the Senning operation.     

Risk-stratified nosocomial infection surveillance in a neonatal intensive care unit: Report on 24 months of surveillance

Objective : To document the nosocomial infection rate in a single neonatal intensive care unit (NICU) in terms of patient workload and device utilization.
Methodology : Nosocomial infections have been identified and documented by the methodology described by the National Nosocomial Infection Surveillance System (NNIS), Centres for Disease Control, Atlanta. In addition, antibiotic usage has been surveyed in the NICU and standardized measures of patient exposure to antibiotics stratified by birthweight and gestational age have been described.
Results : Overall nosocomial infection rates compared favourably with the published NNIS figures at 6.2 infections per 100 admissions or 4.8 per 1000 patient days. Infection rates were significantly higher in lower birthweight groups. Device-related infection rates in each birthweight cohort were also very close to published figures and varied less with birthweight group. Antibiotic exposure averaged 12% of total admission days, less than previously published data.
Conclusions : The NNIS system is applicable to Australian NICU and provides an effective tool for monitoring infection episodes.     

Inhibition of purine catabolism by benzbromarone in isolated rat liver cells. Comparison with allopurinol and probenecid

Benzbromarone, a potent uricosuric agent, inhibited allantoin production in isolated hepatocytes at concentrations half to ten times greater than therapeutic plasma levels of the drug. In addition, the drug at these concentrations also markedly inhibited xanthine oxidase (EC 1.2.1.37), an enzyme involved in the regulation of this pathway. We found that allopurinol is several times superior to benzbromarone in the lowering of allantoin production (if they are compared in terms of their relative therapeutic levels), and that probenecid had no effect on it.     

Lipid composition, fluidity and enzymatic activities of rat liver plasma and mitochondrial membranes in dietary obese rats

Total lipids and fatty acid composition were determined in liver plasma and mitochondrial membranes from control and dietary obese rats after 4 weeks of the experimental period. The lipid composition of liver plasma and mitochondrial membranes showed an increase of triacylglycerols in obese rats. The liver plasma membranes showed a decrease of saturated/unsaturated fatty acid ratio and an increase of (n-6) polyunsaturated fatty acids, whereas the (n-3) polyunsaturated acids were decreased. Contrary to what occurs with plasma membranes, few modifications were observed in mitochondrial membranes. Changes of the fatty acid composition of the phospholipid bilayer are of potentially great importance in structural and functional parameters of membrane. Fluidity of liver plasma membranes of dietary obese rats was highly increased, while the mitochondrial ones remained unchanged. These results can be well explained by the decreased saturated/unsaturated fatty acid ratio. A significant decrease of (Na+-K+) ATPase activity (a membrane bound enzyme) was found in plasma membranes of dietary obese rats. Mitochondrial enzymatic activities and oxidative phosphorylation showed few changes except a small, but significant decrease of state 3 respiratory rate. In this study we also determined the fatty acid composition of all the foods offered to animals and their daily intakes in order to discuss their possible influence on changes in structural and functional membrane parameters.     

消旋棉酚拆分的研究——Ⅳ.苏(-)或(+)-1-(对硝基苯基)-1,3-二羟基丙胺-2为拆分剂

本文介绍以光学活性苏-1-(对硝基苯基)-1,3-二羟基丙胺-2为拆分剂,与消旋棉酚缩合,用常压柱色谱或溶剂结晶法分离得到两个光学纯的非对映体,然后分别水解得(+)和(-)-棉酚。     

Proton spectroscopic imaging (Dixon method) of the liver: clinical utility

The contribution of proton spectroscopic (PS) imaging to magnetic resonance (MR) imaging of the liver was assessed at 0.5 T in 55 patients with known or suspected hepatic malignancy. PS images were compared subjectively with T1- and T2-weighted spin-echo (SE) images for hepatic lesion detection and conspicuity. For hepatic metastases (n = 27), PS images were equal to T1-weighted images in lesion detection in 17 patients but showed fewer lesions in five patients and false-negative results in two. When compared with T2-weighted images, PS images depicted more lesions in six patients, an equal number of lesions in 18, and fewer lesions in two. Hepatomas (n = 8) were detected with each sequence in all patients. Hepatomas were often more conspicuous on PS images than on T2-weighted images; they were of equal conspicuity on PS and T1-weighted images in most cases. Whereas fatty infiltration (n = 16) appeared on PS images as areas of low signal intensity similar to that of paraspinal muscle, it produced no detectable abnormality on either T1- or T2-weighted images. PS imaging is inferior to T1-weighted SE imaging in the detection of hepatic metastases. The major role of PS imaging at intermediate field strength is to differentiate focal fatty infiltration from hepatic metastases.     

Malignant jejunal strictures after Whipple procedure: stenting with large-bore tubes and use of combined transhepatic and peroral approach

Malignant strictures of the afferent jejunal limbs are difficult to treat. Surgical revision and chronic external drainage, two commonly used palliative procedures, have significant associated morbidity. A combined transhepatic and peroral approach was used to stent malignant jejunal strictures in two patients, allowing antegrade internal drainage of biliary and pancreatic secretions. Excellent palliation was achieved, and there were no associated complications.     

Intracerebral pneumatocele: CT findings

Two cases of intracerebral pneumatocele following trauma are presented. One to two months after initial treatment both patients had deteriorating neurologic status. The diagnosis was made by radiography. When a pneumatocele is suspected clinically, computed tomography can play a vital role in determining the precise location of the gas collection, its relationship to the fracture site, and the amount of mass effect on the brain.