Israel Medical Association Journal

Background: The transfer of therapeutic genes into malignant brain tumors has been the subject of intense pre­clinical and clinical research in recent years. Most approaches have used direct intratumoral placement of a variety of vectors and genes, such as retroviruses or adenoviruses carrying drug-susceptibility genes, modified replication-competent herpes virus, and several vectors carrying tumor suppressor genes such as the p53 gene. However, clinical results have so far been disappointing, mainly due to the limited ability to effectively distribute the genetic material into the target cell population. Accordingly, alternative delivery approaches into the central nervous system, e.g., intravascular, are under investigation. Genetic vectors administered intravascularly are unlikely to penetrate the blood-brain barrier and transfer a gene into brain or tumor parenchyma. However, intravascular delivery of vectors may target endothelial cells lining the blood vessels of the brain. Since endothetial cells participate in a variety of physiological and pathological processes in the brain, their modulation by gene transfer may be used for a variety of therapeutic purposes. Angiogenically stimulated endothelial cells within tumors replicate rapidly and hence may become targets for retroviral-mediated gene transfer.

Objective: To assess the anti-tumor effect of transferring a drug-susceptibility gene into endothelial cells of the tumor vasculature.

Methods: As a model for this approach we delivered concentrated retroviral vectors carrying a drug-susceptibility gene via the internal carotid artery of rats with malignant brain tumors. The safety and efficacy of this approach, without and with subsequent treatment with a pro-drug (ganciclovir). was evaluated.

Results: No acute or long-term toxicity was observed after intraarterial infusion of the vector. Treatment with ganciclovir resulted in variable hemorrhagic necrosis of tumors, indicating preferential transduction of the angiogenically stimulated tumor vasculature. This was accompanied by severe toxicity caused by subarachnoid hemorrhage and intracerebral hemorrhage in vascular territories shared by the tumor and adjacent brain.

Conclusion: The data indicate that endothelial cells can be targeted by intraarterial delivery of retroviral vectors and can be used for devising new gene therapy strategies for the treatment of brain tumors.

The novel neuropeptides hypocretin/orexin have recently been located on the lateral hypothalamus cells. This system has been linked to the regulation of both feeding and sleep, and recent studies have found an association between a defect in these neuropeptides and narcolepsy. We conducted a MED­LINE review of all the articles published since the discovery of hypocretin/orexin peptides, narrowing the field to the relation­ship between these neuropeptides and sleep. The finding of a deletion in the transcription of the hypocretin receptor 2 gene in narcoleptic Doberman pinschers and the development of a knockout of the hypocretin gene in mice pointed to the relevance of this system in the sleep-wake cycle. We provide further evidence of the role of the hypocretin/orexin system in narcolepsy and in sleep regulation and present an integrative model of the pathophysiology of narcolepsy. The discovery of the link between these peptides and narcolepsy opens new avenues to both the understanding of sleep mechanisms and therapeutic implications for sleep disorders.

Background: Familial Mediterranean fever is a genetic disorder manifested by recurrent attacks of peritonitis, pleuritis and arthritis, and characterized by clinical, histological and laboratory evidence for localized and systemic inflammation. Colchicine treatment usually prevents the attacks and the associated inflammation. Inflammation of atherosclerosis and ischemic heart disease.

Objective: To study the effect of inflammation and its prevention on occurrence of IHD, using FMF as a model.

Methods and Patients: We studied the presence of IHD and its risk factors in 290 FMF patients aged 40 years or more, and in two control groups – 233 spouses of the FMF patients’ and 126 patients with inflammatory diseases obtained from other outpatient clinics. FMF patients were also compared with age and gender-matched individuals from the population reference data of the Israel Ministry of Health.

Results: The prevalence of IHD in FMF patients was significantly lower than in the group of controls from other outpatient clinics (15.5% vs. 30.2% P< 0.05) and comparable with their spouses (11.2%) and with the matched general population in Israel (16%).

Conclusion: These findings suggest that despite the evidence of recurrent inflammation, colchicines-treated FMF patients are not more predisposed to IHD than the normal population.

Objective: To evaluate the feasibility of using combined clinical and histomorphometric features to construct a prognostic score for the individual patient with localized renal cell carcinoma.

Patients and Methods: We studied 39 patients with pT1 and pT2 RCC who underwent radical nephrectomy between 1974 and 1983. Univariate and multivariate analyses were used to determine the association between various prognostic features and patient survival.

Results: The most important and independent predictors of survival were tumor angiogenesis (P=0.009), nuclear DNA ploidy (P=0.0071), mean nuclear area (P=0.013), and mean elongation factor (P=0.0346). Combination of these variables enabled prediction of outcome for the individual patient at a sensitivity and specificity of 78% and 89% respectively.

Conclusion: Our results indicate that no single parameter can accurately predict the outcome for patients with localized RCC. Combination of neovascularity, DNA content and morphometric shape descriptors enabled a more precise stratification of the patients into different risk categories.
 

Background: Secundum atrial septal defect is a common congenital heart defect that causes right heart volume overload and produces symptoms usually after the third decade of life. Treatment until the last few years has been open heart surgery.

Objective: To review our early experience with transcatheter closure of ASD2 using the Amplatzer septal occluder.

Methods: Between November 1999 and February 2000, 20 children and young adults with a median age of 9.1 years (4.2-35.1 years) were referred for transcatheter closure of ASD2. Diagnosis was established by transthoracic echocardiography. Implantation was performed under general anesthesia through the femoral vein with the guidance of transesophageal echocardiography and fluoroscopy. Femoral arterial puncture was performed for blood pressure monitoring during the procedure. The device size chosen was similar to the balloon-stretched diameter of the ASD2.

Results: Implantation was completed successfully in 18 patients. Two patients were referred for elective surgery: one had an unsuitable anatomy for transcatheter closure by TEE in the catheterization laboratory and the device could not implanted properly, the other patient had a large multiperforated septal aneurysm that was retrieved. Mean ASD2 diameter by TTE and TEE was similar (13.9 + 3 mm, 13.4 + 3.5 mm) and mean stretched diameter was 18.3 + 4.3 mm. Mean Qp:Qs (pulmonary flow: systemic flow) was 2.2 + 0.6. Mean fluoroscopy time for the procedure was 14.8 + 4.8 minutes.

The patients were discharged the day after the procedure.

Four patients had a tiny leak immediately post-procedure, and none had a leak at one month follow-up. The only complication was a small pseudoaneurysm of the femoral artery in one patient, that resolved spontaneously.

Conclusion: Transcatheter closure of ASD2 with the Amplatzer septal occluder is a safe and effective alternative to surgical closure. Long-term outcome has to be evaluated.

Objective: To investigate whether cigarette smoking has an additive effect on the clinical presentation and course of disease in Helicobacter pylori-positive dyspeptic patients.

Patients and Methods: The study group comprised 596 consecutive H. pylori-positive dyspeptic patients (334 males and 262 females, mean age 50.6, range 12--81 years). Following upper gastrointestinal endoscopy, patients were subdivided by diagnosis as follows: Non-ulcer patient group (n=312: gastritis 193, duodenitis 119), gastric ulcer (n=19), and duodenal ulcer (n=265). H. pylori infection was confirmed by histology and/or rapid urease test. In addition, 244 patients had a positive 14C-urea breath test prior to antimicrobial treatment. The patients' medical history and smoking habits were obtained using a detailed questionnaire completed by the patients and their referring physicians.

Results: There were 337 non-smoking patients, 148 current smokers and 111 past smokers. Gastric and duodenal ulcers were significantly less prevalent in non-smokers than in current or past smokers (gastric 1.8%, 4.1%, 6.3%; duodenal 39.8%, 50%, 51.4%, respectively) (P0.05). The incidence of gastrointestinal bleeding was significantly lower in non-smokers than in current or past smokers (7.1%, 8.1% and 20.7%, respectively) (P0.05). Bacterial density, as assessed by the UBT value in 244 patients, was higher in non-smokers (mean 352.3273 units) than in past smokers (mean 320.8199) or current-smokers (mean 229.9162) (P0.05). Logistic regression analysis revealed that male gender, current smoking, and immigration from developing countries were all significant independent risks for developing duodenal ulcer, while only past smoking was associated with a higher rate of upper gastrointestinal bleeding in the past.

Conclusions: In H. pylori-positive dyspeptic patients, current smoking as well as male gender and immigration from developing countries are associated with an increased risk for duodenal ulcer. This effect does not seem to be related to the bacterial density or increased urease activity of H. pylori organisms.

Objective: To investigate the clinical, laboratory and radiological findings of the disease.

Methods: During the years 1995-88 five patients with primary epiploic appendigitis were diagnosed at our institution. The clinical, laboratory and imaging results were summarized and compared to previously reported series. Emphasis was placed on the computed tomography findings, which are the gold standard for diagnosis.

Results: All our patients (two males and three females, mean age 47 years) presented with left lower quadrant abdominal pain. CT proved to be the imaging modality of choice in all patients by showing a pericolic fatty mass with an increased attenuation as compared to normal abdominal fat. In all cases the mass was surrounded by a high attenuation rim, and focal stranding of the fat was observed. In no case was there thickening of the adjacent bowel wall. This serves as an important, and previously unreported, clue for diagnosis.

Conclusion: Primary epiploic appendagitis is a relatively rare condition that may be clinically misdiagnosed, resulting in unnecessary surgical intervention. Judicious interpretation of CT may lead to early diagnosis and ensure proper conservative treatment.