Effects of Pravastatin on Plasma Lipid Concentrations in Poloxamer 407-Induced Hyperlipidemic Rats

A new animal model of hyperlipidemia is being developed using the nonionic surfactant poloxamer 407 (P-407). We investigated the impact of pravastatin on P-407-induced hyperlipidemia. Twenty rats received P-407 300 mg intraperitoneally to induce hyperlipidemia, and 20 control rats received saline injection. Pravastatin was administered orally to an equal number of rats in both groups using three different regimens. A fourth group did not receive pravastatin. At 24 hours after injection, total cholesterol levels in two of the pravastatin groups were 28% and 34% lower than those in animals that did not receive pravastatin (p≤0.01). At 48 hours, triglyceride levels were significantly lower in all pravastatin groups (21–44%) versus animals not receiving pravastatin. Pravastatin diminished the effects of P-407 on lipoproteins. This new animal model may be useful in screening for investigational antihyperlipidemic agents.     

Kyphoplastie und Vertebroplastie bei Frakturen im hohen Lebensalter

Kyphoplasty and vertebroplasty are two minimally invasive percutaneous techniques used for treatment of osteoporotic vertebral compression fractures in the thoracic and lumbar spine. The injection of polymethylmetacrylate (PMMA) is often a final attempt at therapeutic treatment of complications due to such fractures. Vertebroplasty involves injection of cement via one or both pedicles under high pressure, thus filling and stabilizing the vertebra without reduction of fracture. Extravertebral cement leakage is a common complication: an intact posterior wall normally prevents cement leakage into the epidural space. Kyphoplasty involves transpedicular inflation of balloon tamps, thus creating a cavity which is then filled with PMMA under low pressure. Restoration of vertebral height is possible and the potential for extravertebral cement leakage lessened.     

Lymphoscintigraphy as a predictor of lymphatic drainage from cutaneous melanoma

Background: If cutaneous lymphoscintigraphy (CL) is accurate in predicting the draining lymph node basins at risk from primary axial melanomas, then regional metastases should only occur in those lymph node basins identified by CL. Methods: This study is a retrospective review of patients undergoing CL for primary axial melanomas from June 1, 1985, until June 31, 1992. Data retrieved included age, gender, number of basins identified, location of basins identified, management of basins, recurrence in lymphatics, development of distant disease, and long-term follow-up. Results: A total of 181 patients underwent elective LND, and 48 patients (27%) had melanoma in the nodes within the dissected basin. Of these 181 patients, seven developed nodal metastases as their site of first recurrence. All seven recurrences were seen at sites dissected or at sites indicated by CL, which the primary surgeon elected not to treat initially. Of the 116 patients observed, 16 (14%) developed lymph node metastases as their first site of recurrence. Fifteen of these 16 patients had their site of lymph node metastases predicted by CL. In this study, CL predicted 98.6% of all lymph node metastases. Conclusions: The high overall reliability of CL as demonstrated by long-term follow-up indicates that the information obtained by CL can be reliably used to guide intervention. Initial evaluation of patients with high-risk cutaneous melanomas at sites with ambiguous lymphatic drainage must include CL in order to determine the draining lymph node basins and to plan therapy. Presented at the 47th Annual Cancer Symposium of The Society of Surgical Oncology, Houston, Texas, March 17–20, 1994.     

Severe acute myocardial infarction during a staphylococcal septicemia with meningoencephalitis

We report the first case of lethal intracranial haemorrhage complicating a treatment by rt-PA in a patient presenting with a simultaneous staphylococcal septicemia with meningoencephalitis and an acute myocardial infarction with cardiogenic shock. The presence of microvascular lesions in the central nervous system seems to be important risk factor for intracranial haemorrhage and we recommend extreme caution in the use of thrombolytic treatment in septicemic patients with acute myocardial infarction, particularly when neurological symptoms are present.     

INTRA-AORTIC BALLOON RUPTURE CAUSING FEMORAL ENTRAPMENT

Rupture of an intra-aortic balloon counterpulsator (IABCP) demands immediate removal. We report a case of thrombus formation within a Datascope IABCP secondary to IABCP rupture, necessitating surgical exploration for removal. There is a disturbing pattern of balloon ruptures with this type of IABCP.     

Health and health services among the Navajo Indians

The Navajo are the largest Indian tribe in the continental U.S. with a population in 1986 estimated at 171,097. The Navajo Nation (Reservation) is located along the borders where Arizona, New Mexico, Colorado and Utah meet. Social and economic changes have accrued among the Navajo at a rapid rate during this century. At present, revenues are derived from oil, coal and uranium and from federal grants and contracts. High unemployment rates have been a major problem among the Navajo.This article reviews health, disease and health care among the present day Navajo. Mortality rates from accidents and suicide are disproportionately high and have as their causes longstanding social and behavioral problems. Although there has been a sharp decline in morbidity and mortality from infectious diseases, there are still major environmental health problems.Sixten S.R. Haraldson, Dr. Med, M.P.H. is Professor of International Development, Clark University and a former Director of the Nordic School of Public Health, Sweden. Address request for reprints to: Dr. Sixten S.R. Haraldson P.O. Box 5, 432 03 Traslovslage, Sweden.The author made study visits to Indian reservations in Arizona in the U.S. in 1974, 1984 and 1985, and had valuable discussions with Catherine Fleshman, M.P.H., B.A. and Kenneth Fleshman, M.D. Both have extensively dealt with health problems among the Navajos and other Native Americans. Dr. Fleshman has practiced clinical medicine and public health with the Indian Health Service for thirty years. Ms. Fleshman is presently conducting health care management implementation studies for a southern Arizona tribe. I am most grateful for their assistance with statistical information and with their unique personal experience.     

Analysis of Various Creatinine Clearance Formulas in Predicting Gentamicin Elimination in Patients With Low Serum Creatinine

Predicted gentamicin elimination rate constants (k_els) using creatinine clearance (C1_cr) estimates from seven equations were compared with k_els calculated from steady-state serum gentamicin concentrations in 186 hospitalized patients. In predicting k_el, the equations varied significantly in precision (mean absolute percentage error), and were particularly imprecise among patients with serum creatinine values of 71 μmol/L or less. Significant differences in bias (mean prediction error) were also observed. All equations using serum creatinine as an element showed improved precision, and most showed reduced bias when a minimum value of 71 μmol/L was used. The Cockcroft-Gault normalized to 72 kg and the Hull equations are among the simplest to calculate and, when using a minimum serum creatinine of 71 μmol/L, had significantly greater precision and less bias than several of the equations. We recommend one of these two methods for predicting gentamicin k_el in patients with low serum creatinine values.     

Licensing and control authority batch release of influenza vaccine in Germany in accordance with EEC regulations

The epidemiological situation calls for almost yearly changes in the antigenic composition of influenza vaccine, thus necessitating fresh licensing procedures. Since the time for bringing a new vaccine onto the market should be relatively short, the following work of all parties involved must be done expeditiously: 1) WHO recommendations on new virus strains and their subsequent adaptation by the EEC (February/March); 2) Distribution of the new virus strains to the International Reference Centers for Influenza in the UK and USA (February/ March); the centers later issue reference materials for the determination of the haemagglutinin antigen concentration (April/May); 3) Production and testing of seed virus by manufacturers, as well as validation of the producer's inactivation process for the new virus strains (May/June); 4) Licensing of the vaccines by the National Control Authority (Paul-Ehrlich-Institute) (June/July); in the case of previously licensed products, the procedure is limited essentially to the approval of the detailed protocol of production and tests on the new virus strains, clinical studies not being required before licensing because of a lack of time; 5) Paul-Ehrlich-Institute's test for batch release, according to Directive 89/342/EEC, besides protocol approval, conducts material testing of the endotoxin and antigen content of each vaccine lot; the assay for the antigen quantification is especially laborious and sometimes must be repeated because of test invalidity.