Gene delivery to glioma cells in rat brain by grafting of a retrovirus packaging cell line

Retrovirus vectors only integrate into the genome of dividing cells and can thus be used to selectively infect tumor cells in the adult rat brain. Gene delivery was assessed by using the retrovirus BAG vector, which bears the Escherichia coli lacZ gene under the MoMLV LTR promoter-enhancer element, and by histochemical staining for bacterial beta-galactosidase activity. Direct injection of this vector (90-900 cfu) into the adult rat brain, with or without prior inoculation of C6 glioma cells (2 x 10(5) cells) resulted in labeling of only a few cells as assessed 1 week later. When the psi 2-BAG packaging line was grafted into the brain, labeled psi 2-BAG cells could be found after 1 day, but not after 5 days, following grafting, suggesting that the grafted cells had been rejected and that no endogenous cells had integrated released vector, or that expression of lacZ had been turned off. In contrast, when the psi 2-BAG packaging line was grafted into a brain region, which had been inoculated previously with rat C6 glioma cells (2 x 10(5) cells), beta-galactosidase labeling of these tumor cells, identified by immunocytochemistry for glial fibrillary acidic protein and S100, could be demonstrated 10 days later. Thus, grafting of retrovirus packaging lines into adult brain provides a mean to infect tumor cells in situ. The grafted packaging cells may continue to release retrovirus particles for an extended period, thus infecting more cells at the stage of division appropriate for viral integration, as compared to inoculation of the virus alone. Grafting of retrovirus packaging cell lines could be used to selectively deliver "killer" or "suppressor" genes to tumor cells in the brain to curtail their growth.     

Detection and survival of Listeria monocytogenes in milk and dairy products

Detection of L. monocytogenes in raw and pasteurized milk, Zabady, Karish, Domiati and Romi cheeses were done in this study using direct and cold enrichment methods. Out of 140 samples 3 samples were positive by cold enrichment and they were 2 of raw milk and one of Domiati cheese. Survival of L. monocytogenes was studied during heat treatment of milk by the sealed tube method of inactivation and it was found that L. monocytogenes inactivated completely at 60 degrees C for 15 minutes. There was a statistically inverse correlation between time of storage of dairy products and viable cell count of L. monocytogenes. PH played an important role in survival of that pathogen.     

Influence of surgery on renal amyloidosis

It is well known that renal amyloidosis (RA) leads to ESRD in a few years. This evolution may be accelerated by several factors such as steroids, renal vein thrombosis, infections or surgery. We report 22 patients (14M,8F) mean age = 41.6 years (13-72) with RA in whom surgery revealed or aggravated renal disease. The group I includes 15 patients with no previous history of renal disease and who developed oedema few days after surgery with acute renal failure in 5 of them. Proteinuria was present in all the cases with a nephrotic syndrome in 10. Percutaneous kidney biopsy (KB) showed renal amyloidosis in all patients (AA+ = 8 cases, AA- = 3 cases). Only 9 patients were followed-up (mean period = 40 months): 2 patients are stationary; 1 is on complete remission 2 are on HD and 4 died. The group II includes 7 patients with a previous history of nephropathy (Histologically proven amyloidosis: 3 CRF = 1, Oedema: 3). All these patients developed oedema few days after surgery with acute RF in 4 patients. KB performed in all of them showed RA (AA+ = 33, AA- = 1). 6 patients were followed up for a mean period of 11 months: 5 died, 1 patient is on HD. The influence of surgery on renal amyloidosis is often unforeseeable. It may have no effect on renal disease, but very often it reveals RA and sometimes dramatically aggravates the course of the disease with occurrence of irreversible CRF. The pathogenic role of surgery on RA is discussed.     

Primitive intracranial ependymomas. Salah-Aza?z institute experience]

PURPOSE: - To assess the outcome and prognostic factors of patients with primitive intracranial ependymomas treated at the department of radiotherapy of Salah-Aza?z Institute. METHODS AND MATERIAL: - Between 1972 and 1997, 31 patients aged one to 53 years received postoperative radiotherapy. There were 16 males and 15 females. Location of tumor was infratentorial in 24 cases and supratentoriel in seven cases. Surgical treatment consisted of complete resection in 14, incomplete resection in 13 and unknown type in four patients. All patients were treated with radiotherapy to the craniospinal axis in 26 cases, whole brain in five cases. RESULTS: - Five years survival rate was 63%. For infratentorial tumors, two patients failed locally, two patients failed locally and at distance and four patients failed only at distance, while one patient with supratentorial tumor relapsed locally. Age, performances status, tumor site, gender and extent of surgery had no impact on survival. The treatment field extent was the only variable predictive of outcome. Patients treated with craniospinal irradiation had a survival rate of 86% compared with 37,5% for patients treated with whole brain irradiation. CONCLUSION:- Infratentorial ependymomas seem to have a worse prognosis than supratentorial ones. Irradiation field extent should be correlated to prognostic factors.     

Primary intramedullary ependymomas: retrospective study of 16 cases]

PURPOSE: To review the radiotherapy department experience in treating primary spinal cord ependymomas (PSCE), analyse prognostic factors and provide treatment recommendations regarding literature review. MATERIALS AND METHODS: Sixteen patients with PSCE received postoperative radiotherapy between 1972 and 1997. There were 10 male and 6 female patients with a mean age of 34 years (range 2-63). Surgery was gross total resection in 2 cases, subtotal resection in 9, biopsy in 4 and of unknown type in one patient. All patients were treated with radiotherapy to the craniospinal axis (4 cases), spinal cord (1 case) and to the site of primary tumour in 11 cases. RESULTS: Five year-survival rate was 73%. Two patients had recurrent tumours within the primary site. Gender, extent of surgery and treatment field extent were not prognostic factors. Histologic type was the only variable predictive of outcome. Patients with myxopapillary type had a 5-year survival rate of 100% compared with 47% for those with other histology types. CONCLUSION: We conclude that aggressive surgery is not necessary in the management of PSCE, localised field radiotherapy is associated with favourable outcome, and tumour grade is an important prognostic factor.     

Therapy of heart failure

The incidence and prevalence of heart failure is on the rise. It has become the single most expensive health care item in the United States and the number one discharge diagnosis in the elderly. The goals of therapy include both prevention and treatment of heart failure. In recent years research studies and randomized clinical trials have revolutionized the understanding of the pathophysiology and treatment of this disease. This article focuses on the medical management of chronic systolic heart failure based on the pathophysiology of the disease. Systolic heart failure is characterized by a decrease in left ventricular function and cardiac output, which results in activation of several neurohormonal compensatory systems. The long term effects of this neurohormonal activation leads to further deterioration of cardiac function. The use of hydralazine and nitrates to reduce the systemic vascular resistance was the first to show an improvement in mortality and morbidity. Then angiotensin converting enzyme inhibitors, by inhibiting the renin angiotensin system, demonstrated a greater improvement in mortality and morbidity. More recently the inhibition of the sympathetic stimulation with beta-blockers has been shown to have an additive effect on morbidity and mortality in combination with angiotensin-converting enzyme inhibitors. Digoxin and diuretics remain important for improving symptoms and decreasing hospitalizations but have not been shown to decrease mortality. The most recent advance in the treatment of cardiac failure is the demonstration that the aldosterone antagonists, spironolactone decreases morbidity and mortality.     

Biochemical study on the hypoglycemic effects of onion and garlic in alloxan-induced diabetic rats.

The present study was carried out to investigate the effects of onion (Allium cepa Linn) and garlic (Allium sativum Linn) juices on biochemical parameters, enzyme activities and lipid peroxidation in alloxan-induced diabetic rats. Alloxan was administered as a single dose (120 mg/kg BW) to induce diabetes. A dose of 1 ml of either onion or garlic juices/100 g body weight (equivalent to 0.4 g/100 g BW) was orally administered daily to alloxan-diabetic rats for four weeks. The levels of glucose, urea, creatinine and bilirubin were significantly (p<0.05) increased in plasma of alloxan-diabetic rats compared to the control group. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), and alkaline and acid phosphatases (AlP, AcP) activities were significantly (p<0.05) increased in plasma and testes of alloxan-diabetic rats, while these activities were decreased in liver compared with the control group. Brain LDH was significantly (p<0.05) increased. The concentration of thiobarbituric acid reactive substances and the activity of glutathione S-transferase in plasma, liver, testes, brain, and kidney were increased in alloxan-diabetic rats. Treatment of the diabetic rats with repeated doses of either garlic or onion juices could restore the changes of the above parameters to their normal levels. The present results showed that garlic and onion juices exerted antioxidant and antihyperglycemic effects and consequently may alleviate liver and renal damage caused by alloxan-induced diabetes.     

Release performance of a poorly soluble drug from a novel, Eudragit-based multi-unit erosion matrix

Mechanisms governing the release of drugs from controlled delivery systems are mainly diffusion, osmosis and erosion. For poorly soluble drugs, the existing mechanisms are limited to osmosis and matrix erosion, that are commonly observed in single unit matrix dosage forms. This study reports formulation and dissolution performance of Eudragit L 100 55 and Eudragit S 100 based multi-unit controlled release system of a poorly soluble thiazole based leukotriene D(4) antagonist, that was obtained by an extrusion/spheronization technique. Effect of triethyl citrate, that was incorporated in the matrix, on the dissolution performance of the drug was also evaluated. In vitro matrix erosion and drug release from the pellets were determined by the use of USP Dissolution Apparatus I, pH 6.8 phosphate buffer, gravimetry and UV spectrophotometry, respectively. Results obtained demonstrated that matrix erosion and drug release occurred simultaneously from the pellets. Pellets eroded with a consequent reduction in size without any change in the pellet geometry for over 12 h. Matrix erosion and drug release followed zero order kinetics. Data obtained strongly suggested a polymer controlled, surface erosion mechanism.