Selective sensitivity of synaptosomal membrane function to cerebral cortical hypoxia in newborn piglets

The effect of hypoxia on the structure and function of the synaptosomal membranes and myelin fraction (glial cells, neuronal cell bodies and axonal membranes) was investigated by measuring Na⁺,K⁺-ATPase activity and levels of lipid peroxidation products in cerebral cortical synaptosomal membranes and myelin fractions obtained from newborn piglets. Hypoxic hypoxia was induced and cerebral hypoxia was documented as a decrease in the ratio of phosphocreatine to inorganic phosphate (PCr/Oi) using³¹P-NMR spectroscopy. PCr/Pi decreased from baseline of2.93 ± 0.76to0.61 ± 0.36 during hypoxia. The synaptosomal membrane Na⁺,K⁺-ATPase activity decreased from a control value of56.6 ± 3.7to40.4 ± 6.0 μgmol Pi/mg protein/h during hypoxia. The level of conjugated dienes increased from zero (reference value) to4.5 ± 2.7 nmol/mg lipid and the level of fluorescent compounds increased from23.5 ± 2.2to92.6 ± 46.4 ng quinine sulfate/mg lipid in the synaptosomal membranes during hypoxia. No change in myelin fraction Na⁺,K⁺-ATPase activity or levels of lipid peroxidation products were noted. These data indicate that sunaptosomal membranes, rich in polyunsaturated fatty acids, are more susceptible to oxygen free radical mediated lipid peroxidative damage during hypoxia.     

Validation of surgical site infection surveillance in orthopedic procedures

BACKGROUND: Valid data are essential for a national surveillance system of nosocomial infections. METHODS: In 8 hospitals conducting surgical site infection (SSI) surveillance for orthopedic procedures, a validation team performed a blinded retrospective chart review (10 operations with reported infections, 40 without) and interviewed infection control nurses. RESULTS: In total, 397 patient charts were reviewed. Positive and negative predictive values for routine surveillance were 94% (95% CI: 89%-99%) and 99% (95% CI: 99%-100%), respectively. When these results were applied to the aggregated surveillance data (403 infections, 10,068 noninfections), sensitivity was 75% (95% CI: 56%-93%) and specificity 100% (95% CI: 97%-100%). The following case finding methods were used: ward visits (in 7/8 hospitals), microbiology reports (5/8), ward notifications by link nurses (8/8), and other nursing (7/8) and medical (5/8) staff. The wound culture rate ranged from 9 to 67 per 1000 patient-days. All hospitals carried out postdischarge surveillance on readmission and all but 1 at follow-up visits and by an additional questionnaire. CONCLUSION: Most SSIs reported by the hospitals were true infections, showing that, when an SSI was reported, the definitions were correctly implemented. Some SSIs were missed, which might be due to weaknesses in case finding. Variation in diagnostic practices may also affect SSI rates.     

Healing of subcapital femoral osteotomies fixed with self-reinforced poly-L-lactide screws: an experimental long-term study in sheep

Subcapital femoral osteotomies of ten young adult sheep were fixed with two bioabsorbable, self-reinforced, poly- L-lactide (SR-PLLA) lag screws of 4.5 mm in diameter. At 3 weeks radiographs were taken to check the reduction and fixation achieved. After follow-up periods of 12 weeks, 1 year and 3 years with three sheep in each group, and of 7 years and 4 months with one sheep, the sheep were killed, and the healing of the osteotomies, degradation and tissue response of the implants were examined radiographically, histologically and microradiographically. All osteotomies healed with a firm bony union. There was no dislocation or wound infection. Histologically, there was no marked tissue response in the bone tissue. At 12 weeks the implants were grossly intact, at 1 year granulation tissue and new bone formation had started to penetrate into the implant, and at 3 years the implant area was mostly replaced by connective tissue and new bone, but implant material was still seen as little islands surrounded by some lymphocytes. At 7 years and 4 months, the implant material had been degraded and replaced by tight bone. Self-reinforced poly- L-lactide lag screws seem to possess adequate mechanical properties and good biocompatibility for this demanding fixation.     

Community-acquired methicillin-resistant Staphylococcus aureus,Finland

Methicillin-resistant Staphylococcus aureus (MRSA) is no longer only hospital acquired. MRSA is defined as community acquired if the MRSA-positive specimen was obtained outside hospital settings or within 2 days of hospital admission, and if it was from a person who had not been hospitalized within 2 years before the date of MRSA isolation. To estimate the proportion of community-acquired MRSA, we analyzed previous hospitalizations for all MRSA-positive persons in Finland from 1997 to 1999 by using data from the National Hospital Discharge Register. Of 526 MRSA-positive persons, 21% had community-acquired MRSA. Three MRSA strains identified by phage typing, pulsed-field gel electrophoresis, and ribotyping were associated with community acquisition. None of the strains were multiresistant, and all showed an mec hypervariable region hybridization pattern A (HVR type A). None of the epidemic multiresistant hospital strains were prevalent in nonhospitalized persons. Our population-based data suggest that community-acquired MRSA may also arise de novo, through horizontal acquisition of the mecA gene.     

Hirschsprung's disease in cartilage-hair hypoplasia has poor prognosis

Purpose: Cartilage-hair hypoplasia (CHH) is a chondrodysplasia with growth failure, impaired immunity, and high incidence of Hirschsprung disease (HD). This study describes the outcome of CHH patients with HD. Methods: Among 147 patients with CHH, 13 were identified to have HD. Their medical records were analyzed for treatment, outcome, and complications of HD and compared with a control group of 169 patients with HD but not CHH. Results: Eight CHH patients had classic HD with rectosigmoid involvement, 2 had long segment colonic disease, and 3 patients had total colonic aganglionosis. Six of the 13 CHH patients (46%) had episodes of enterocolitis before the first surgery. Enterocolitis was complicated by colonic perforation in 2 cases. Eleven CHH patients (85%) had at least one episode of postoperative enterocolitis. Five patients (38%) with CHH and HD had died; 4 of enterocolitis-related septic infection and one of non-Hodgkin's lymphoma. In the control group, preoperative enterocolitis occurred in 14% and postoperative enterocolitis in 8%. Two controls (1.2%) had died. Conclusions: HD associated with CHH has poor prognosis in terms of postoperative morbidity and risk of death. These patients require particular attention during postoperative follow-up to detect potentially lethal complications.     

Autologous stem cell transplantation in patients with mantle cell lymphoma

High-dose therapy followed by autologous stem cell transplantation (ASCT) has been considered a potential treatment approach in order to improve the poor prognosis in mantle cell lymphoma (MCL), but its role has not yet been clearly established. We analyzed retrospectively the outcome and prognostic factors in 48 consecutive patients with MCL scheduled for ASCT in five transplant centers. In 14 patients (29%), a sufficient amount of stem cells could not be collected. Mobilization failure was associated with female sex, blastoid cytology, and low hemoglobin level. Altogether 35 patients underwent ASCT, 24 patients as part of the first-line treatment and 11 patients later. After transplantation 28 patients (80%) remained in or achieved remission. Two patients died of transplant-related complications. During the median follow-up time of 38 months, nine patients have relapsed. The median event-free survival (EFS) was 39 months. Age over 60 years and elevated C-reactive protein level at diagnosis were associated with poorer outcome after transelantation. ASCT is an effective treatment in MCL with a high response rate and a longer survival than seen in conventionally treated patients. However, no plateau was seen in the EFS curve after ASCT. Whether cure Can be achieved in a proportion of patients with ASCT is currently unknown and should be studied in larger patient series with a longer follow-up.     

Risperidone as an antidote to hallucinogenics -should it be prescribed?

A novel clinical and ethical problem is discussed. There are patients who want to use atypical neuroleptics as a self-administered antidote to illicit drugs. Copyright 2000 John Wiley & Sons, Ltd.