Israel Medical Association Journal

Sex steroid hormones (estrogens, progestagens and androgens) have been associated with healthy and neoplastic pancreatic biology, although the precise significance of the findings has not been well established. Receptors for the three different types of SSH are expressed in normal and tumoral pancreatic tissue with varying profiles related to cell origin (exocrine or endocrine), to type of neoplasm. and probably even to tumoral behavior. The activity of specific enzymes involved in the synthesis and transformation of SSH are increased in some neoplastic pancreatic tissues, which may influence the circulating concentrations of these hormones, such as the low serum testosterone: dihydrotestosterone ratio described in male patients with pancreatic carcinoma. Different patterns of age and gender-related incidence and growth of neoplasms have been identified. Experimental studies have shown that pancreatic carcinogenesis is promoted or inhibited by SSH. At present, the data supporting hormonal manipula­tion for the treatment of these tumors are non-conclusive. Normal and tumoral pancreatic tissues may be regarded as a target for SSH and an additional site of biosynthesis. The influence of these hormones on physiological activities is not well known but should be further explored. The study of SSH in pancreatic neoplasms will provide clues about its origin, development, tumoral behavior, prognosis and more specific hormonal therapy. We review here the evidence favoring the role of SSH and their possible clinical implications in pancreatic function.

Background: Congenital subependymal pseudocysts are incidental findings that are found in 05-5.2% of neonates during postmortem examination or head ultrasonography. In our institution we detected 10 neonates with CSEPC.

Objective: To investigate associated etiological factors, morphologic characteristics and outcome of CSEPC.

Methods: We performed a meta-analysis of the literature on CSEPC (1967-98), including our 10 cases.

Results: A total of 256 cases of CSEPC were analyzed. Ultrasound diagnosed 77.6% of CSEPC 48.8% were bilateral and 53.4% were located in the caudothalamic groove or head of caudate nucleus. Altogether, 93.5% resolved during 1-12 months of ultrasonographic follow-up. Compared to the general neonatal population, the following features were more prevalent in the CSEPC population: prematurity, maternal vaginal bleeding, preeclamptic toxemia, intrauterine growth restriction, asphyxia, fetal cytomegalovirus and rubella infec­tions, congenital malformations, chromosomal aberrations, infant mortality, and neurodevelopmental handicap. The risk for neurodevelopmental handicap was significantly higher when CSEPC were associated with fetal infections, IUGR, malformations and chromosomal aberrations, or persistence of CSEPC during follow-up. CSEPC infants without any of these four conditions had a low risk for neurodevelopmental handi­cap.

Conclusions: CSEPC are morphologic features of various underlying conditions encountered in the fetus. Association of CSEPC with IUGR, fetal infections, malformations and chromosomal aberrations or persistence of CSEPC indicates a higher risk for future neurodevelopmental handicaps, probably because of the deleterious effects on the fetal brain that are inherent in these conditions. A favorable outcome is expected in the absence of these risk factors.
 

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.

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.
 

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.

Background: Tumor necrosis factor is associated with various local and systemic inflammatory sequelae following snakebite. Xanthine oxidase is a principal mediator of remote tissue injury (e.g., lungs, heart, liver).

Objective: To investigate in a snakebite-like animal model the as yet unexplored role of TNF and XO in mediating organ damage following snakebite.

Methods: Sprague-Dawley rats were injected intramuscularly with a non-lethal 500 g/kg dose of Vipera aspis venom (n=10) or saline (n=10). Blood pressure and heart rate were continuously monitored, TNF- was measured in the blood, and total XO + xanthine dehydrogenase activity was assessed in various tissues. Lung histology and permeability indices were analyzed.

Results: Venom injection caused a significant (P0.05) reduction in both heart rate and invasive arterial pressure. The blood circulating TNF levels were significantly higher in the intoxicated group (P0.05 vs. saline group), with changes seen at 30 minutes from intoxication in both groups. Total XO + XDH activity in the kidney, lung and liver of the venom-injected group was significantly (P0.05) higher than in the saline group, while the activity in the heart was similar.

Conclusions: The mediation of remote organ and hemodynamic changes following intramuscular injection of a non-lethal dose of Vipera aspis venom can be attributed partly to TNF and partly to XO. More research is needed to better understand the role of either compound and the time frame of their activity before specific antagonists can be introduced for snakebite management.