Israel Medical Association Journal

Background: Previous data showed that new recombi­nant hepatitis B virus vaccine, which contains the S-protein component of the HBV surface together with the Pre-S₁ and Pre-S₂, is considerably more immunogenic than a second-generation recombinant I-IBV vaccine.

Objectives:To compare the immunogenicity and safety of a novel recombinant HBV vaccine S1, Pre-S₁ and Pre-S₂ protein components of the hepatitis B surface antigen - Bio­TM

Hep^TM 10 לg dose, to a licensed vaccine containing only the S-protein component - Engerix-B, 20 לg dose.

Methods: A prospective randomized study included 524 adults - 260 in the Bio-Hep group and 264 in the Engerix-B group. Both vaccines were administered in a three-dose regimen given at 0, 1 and 6 months, and adverse events were recorded on a diary card 5 days after each vaccination. lmmunogenicity was tested by measuring anti-hepatitis B surface antibody.

Results: One month after the third injection, 98% of the BioHep^TM subjects were found to be seroprotected vs. 85.1% of the Engerix-B group. In addition, the geometric mean titers were 2,203 mlU/ml and 326 mlU/ml in the Bio-Hep-B and Engerix-B groups respectively. An immunogenic advantage of Bio-Hep-B was suggested by the rapid onset of antibody response - 66.5% were seroconverted one month after the first injection as compared to 19.3% in the Engerix-B group. No unexpected adverse events were observed, and the recorded events were mild in both groups.

Conclusions: BioHepTM, a novel recombinant HBV vaccine containing 5, Pre-S₁ and Pre-S₂ protein components. at a lower dose, is safe and more immunogenic than the conventional HBV vaccine that contains only S protein.

Background: The impact of repeated surgical resection on the survivorship of patients with malignant astrocytomas is an issue of some controversy in the medical literature.

Objectives: To clarify this issue through a retrospective analysis of treatment outcomes in a brain tumor clinic.

Methods: The patient records from the Brain Tumor Clinic at Hahnemann University Hospital for the period 1988 to 2000 were reviewed. From these, 112 cases of glioblastoma multiforme and 50 cases of anaplastic astrocytoma were chosen for analysis.

Results: The group of patients with glioblastomas showed a median survival of 415 days. When analyzed as subgroups based on the number of surgical resections, the median survival was 393 days in the group with biopsy only, 380 days in the group with one surgical resection, and 548 days in the group with two or three resections. Using the Kaplan-Meier method to generate survival plots and the log rank test to compare groups, repeat debulking was found to be a significant predictor of survival (P= 0.1 73). The group of patients with anaplastic astrocytomas showed a median survival of 1,311 days. When analyzed by subgroups, the patients with biopsy only had a median survival of 544 days, those with one debulking 1,589 days and those with two or three debulkings 1,421 days. There was a trend toward increased survival with debulking and the log rank test again showed statistical significance (P 0.1998).

Conclusions: This study indicates that repeated surgical resections offer increased survival for both glioblastomas and anaplastic astrocytomas.
 

Background: High dose interleukin-2 therapy, adminis­tered in bolus, is considered to be a reasonable treatment option in a selected group of patients with metastatic malignant melanoma.

Objectives: To present our experience using this mode of therapy in 21 patients with metastatic melanoma.

Materials and Methods: The 21 patients in our study group comprised 13 men and 8 women with a mean age of 46 years (range 29-63). Their metastatic disease was present in all extracranial sites, dermal and sub-dermal metastases being the most common (15 patients had at least one site, in addition to other locations of metastases). Patients with intracranial disease were excluded due to the poor effectivity of IL-2 at this site. Treatment comprised a course of 2 weeks of therapy with a 1 week rest interval between. Radiological and physical evaluation was performed 6-8 weeks after the first course. If a response was achieved a second course of therapy was given. Patients received up to 14 planned doses of IL-2 in each week, 720,000 lU/kg of IL-2 per dose iv. in 15 minutes. All treatments were given in the surgical ward, and only one patient was hospitalized in the intensive care unit.

Results: Of the 21 patients, one had a complete response that has lasted for 17 months and 5 patients had a partial response (range 3 months to 3 years). One patient died during treatment, and one patient who refused further treatment because of no response died a few days after completion of treatment. Prior to therapy three of the responders had received autologous vaccines with good immunological response (P=0.115). Toxic side effects were significant, but they were treated successfully with no residual damage.

Conclusions: High dose IL-2 can be administered safely in a surgical department. The response rates achieved in this series justify the use of high dose IL-2 in a selected group of patients. To improve response rates, a combination of auto­logous vaccines prior to high dose IL-2 may be recommended.

Knowledge on the pathophysiology of irritable bowel syndrome has evolved, beginning with disturbances in motility to visceral hypersensitivity, and ultimately to alterations in brain-gut bi­directional communication, where neurotransmitters such as serotonin play a key role. Recently, a multicomponent disease model that integrates all these alterations was proposed. This model is divided into physiological, cognitive, emotional and behavioral components that explain the gastrointestinal as well as the constitutional symptoms. In recent years there has been an explosion of research together with new developments in pharmacological treatments for lBS that support each compo­nent of this model. This review presents recent data in favor of these alterations in IBS.

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.

Objectives: To analyze the incidence of mesothelioma in Israel during the years 1960-96, and to project its trend for the following years.

Methods: We conducted a population-based study of the incidence of mesothelioma reported to the Israel Cancer Registry during 1960-96. Time trends were analyzed from data on the annual import of asbestos to Israel, which may indicate the magnitude of past exposure. Based on these findings, trends in the incidence of mesothelioma in Israel were projected for the subsequent years.

Results: A total of 327 cases of mesothelioma were reported to the Israel Cancer Registry during the study period. The incidence in Jews was higher than in Arabs (age-standardized incidence rate 2.64 vs. 1.35 per million/year, respectively). Among the Jewish population, Israeli-born males and males born in Europe and America showed the highest incidence (ASR 4.23 and 4.15 per million/year, respectively). Israeli-born males were 20 years younger than Jewish males born elsewhere. The incidence was twice as high among males than females and increased sevenfold from its nadir (1.17 per million/year) in 1978--80 to its peak (8.5 per million/year) in 1993-96. During a similar period the incidence among females increased from 0.33 to 2.56 per million/year. The incidence in both sexes does not appear to level off. The large wave of immigration from the former Soviet Union that began in 1989 only partly accounts for the increased incidence in 1993-96. The time trend in the incidence of mesothelioma in both sexes parallels the use of asbestos in Israel, which peaked in the years 1976-78.

Conclusions: The incidence of mesothelioma in Israel has increased sharply in recent years, unrelated to a wave of immigration from East Europe, and is predicted to continue to rise for another 10-15 years.

Background: A previous study on Hodgkin's lymphoma in southern Israel found that Bedouin patients had an increased rate of Epstein-Barr virus expression in their tumor cells.

Objectives: To determine the influence of the patients' communities on the pattern of disease in HL.

Methods: We compared the clinical features, demographic data, stage at diagnosis, treatment modality and outcome, as well as laboratory findings, in four community-based subgroups. These groups comprised kibbutz residents (n=11), Bedouin (n=19), new immigrants from the former USSR (n=22), and town-dwellers (n=82).

Results: The Bedouin patients differed significantly from the new immigrants and town-dwellers, particularly regarding the rate of EBV sequences in the tumor tissues, and a poorer response to treatment. The kibbutz patients did not differ significantly from the other populations regarding most of the parameters studied, but showed an intermediate expression of EBV antigens compared to Bedouin patients and the rest of the cohort.

Conclusions: This study indicates that HL may behave differently in different population groups in a given geographic area. Notably, the Bedouin patients showed markedly different clinical and biological patterns of this malignancy. 

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HL= Hodgkin's lymphoma

EBV= Epstein-Barr virus

Background: Spectral analysis of heart rate variability has been shown to be a reliable non-invasive test for quantitative assessment of cardiovascular autonomic regulatory responses, providing a window reflecting the interaction of sympathetic and parasympathetic tone. Alterations in autonomic function are associated with a variety of physiologic and pathophysiologic processes and may contribute substantially to morbidity and mortality. Our previous study shows that patients with post-traumatic stress disorder have significantly lower HRV compared to controls, reflecting a basal autonomic state characterized by increased sympathetic and decreased parasympathetic tone.

Objectives: To apply this tool to PTSD patients treated with selective serotonin re-uptake inhibitors in order to assess the impact of such treatment on the autonomic dysregulation characterizing these patients.

Methods: Standardized heart rate analysis was carried out in nine PTSD patients treated with SSRI agents and compared to that in a matched control group of nine healthy volunteers and in nine untreated PTSD patients, based on a 15 minute resting electrocardiogram.

Results: Our preliminary results show that the HRV parameters indicating autonomic dysregulation, which characterize PTSD patients at rest, are normalized in responding patients by use of SSRIs. Neither the clinical implications of these findings nor their physiological mechanisms are clear at present, although we presume that they reflect a central effect, since the peripheral autonomic effects of SSRIs are relatively negligible.   

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HRV = heart rate variability

PTSD = post-traumatic stress disorder

SSRI = selective serotonin re-uptake inhibitor