Israel Medical Association Journal

Background: Infectious agents are important in the pathogenesis of autoimmune disease since they are a major part of the environmental trigger of autoimmunity. A negative relationship between latitude and infectious disease species richness has been suggested.

Objectives: To examine whether their prevalence differs in two latitudinally different populations.

Methods: The prevalence of infections with Toxoplasma gondii, rubella virus, cytomegalovirus, Epstein-Barr virus and Treponema pallidum was compared between subjects from Italy and Colombia.

Results: We found high titers of antibodies against four of five microorganisms tested, Toxoplasma gondii (50.8%), rubella virus (German measles) (75%), cytomegalovirus (86.3%), Epstein-Barr virus (83.3%) and Treponema pallidum (6.3%) in completely healthy individuals from a tropical country (Colombia) and a European country (Italy). Differences between two groups of volunteers were noted regarding two infectious agents. The prevalence of immunoglobulin G anti-rubella antibodies was significantly higher among Italian subjects (85% vs. 67.9%, P = 0.002), whereas antibodies against CMV[1] were less prevalent among Italian as compared to Colombian subjects (77% vs. 92.9%, P < 0.001).

Conclusions: These differences might also result in a different tendency towards development of autoimmune diseases associated with these infectious agents in different populations.

Background: Surgery for spinal stenosis is a frequent procedure in elderly patients. Presentation, hospital course and outcome of disease, including pain perception, may vary among patients of different ethnic origin.

Objectives: To evaluate whether differences in various medical indicators can explain differences in pain perception between two ethnic groups

Methods: We conducted a case-control study on the experience of two spinal units treating a mixed Arab and Jewish population, and compared the data on 85 Arab and 189 Jewish patients undergoing spinal lumbar surgery.

Results: Arab patients were younger (P = 0.027), less educated (P < 0.001), had a higher body mass index (P = 0.004) and included a higher proportion of diabetics (P = 0.013). Preoperative pain intensity (P = 0.023) and functional disability (P = 0.005) were more prominent, and factors associated with pre- or postoperative pain perception differed between the two ethnic groups. Despite these differences, results on follow-up were similar with respect to pain perception and level of disability.

Conclusions: A better understanding of ethnic differences is crucial for predicting surgery outcomes.

Background: Catheter ablation is assuming a larger role in the management of patients with cardiac arrhythmias. Conventional fluoroscopic catheter mapping has limited spatial resolution and involves prolonged fluoroscopy. The non-fluoroscopic electroanatomic mapping technique (CARTO) has been developed to overcome these drawbacks.

Objectives: To report the early and late outcome in patients with different arrhythmias treated with radiofrequency ablation combined with the CARTO mapping and navigation system.

Methods: The study cohort comprised 125 consecutive patients with different cardiac arrhythmia referred to our center from January 1999 to July 2005 for mapping and/or ablation procedures using the CARTO system. Forty patients (32%) had previous failed conventional ablation or mapping procedures and were referred by other centers. The arrhythmia included atrial fibrillation (n=13), atrial flutter (n=38), atrial tachycardia (n=25), ventricular tachycardia (n=24), arrhythmogenic right ventricular dysplasia (n=9), and supraventricular tachycardia (n=16).

Results: During the study period, a total of 125 patients (mean age 49 ± 19 years, 59% males) underwent electrophysiological study and electroanatomic mapping of the heart chambers. Supraventricular arrhythmias were identified in 92 patients (73 %) and ventricular arrhythmias in 33 (27%). Acute and late success rates, defined as termination of the arrhythmia without anti-arrhythmic drugs, were 87% and 76% respectively. One patient (0.8%) developed a clinically significant complication.

Conclusions: The CARTO system advances our understanding of arrhythmias, and increases the safety, efficacy and efficiency of radiofrequency ablation.

Background: The Muslim Circassians in Israel represent a unique ethnic community, distinct from Jews and Arabs. This endogamous group has a limited genetic variability that allows studying risk factors associated with type 2 diabetes.

Objectives: To estimate the prevalence of type 2 diabetes among Israeli Circassians and its correlation to obesity and genetic susceptibility.

Methods: Israeli Circassian women (n=450) and men (n=289) older than 35 were included in the study. They were classified as having or not having diabetes, and their risk factors, including hypertension, body mass index, family history of diabetes, and laboratory tests, were examined retrospectively.

Results: The age-adjusted prevalence of diabetes among the 739 participants was 12% (men 14.6%, women 10.7%). It was higher among those with BMI[1] > 30 than in those with lower BMI and a family history of diabetes without high BMI. But the risk of diabetes with BMI > 30 plus a family history was three times higher than when these factors were missing (odds ratio 2.96, 95% confidence interval 1.30–6.6). Multivariate analysis, however, found familial history of diabetes to be the strongest risk factor, independent of obesity (OR[2] 2.47, 95% CI[3] 1.45–4.20).

Conclusions: The results yielded by this homogeneous Circassian population, sharing the same environmental influences and having an endogamous pattern of marriage, suggest a role of genetic risk factors for diabetes. Israeli Circassians are suitable for additional genetic studies that may lead to the identification of susceptibility genes for type 2 diabetes.

The adult human heart has limited regenerative capacity and, therefore, functional restoration of the damaged heart presents a great challenge. Despite the progress achieved in the pharmacological and surgical treatment of degenerative myocardial diseases, they are still considered a major cause of morbidity and mortality in the western world. Repopulation of the damaged heart with cardiomyocytes represents a novel conceptual therapeutic paradigm but is hampered by the lack of sources for human cardiomyocytes. The recent derivation of pluripotent human embryonic stem cell lines may provide a solution for this cell sourcing problem. This review will focus on the derivation of the hESC[1] lines, their mechanism of self-renewal, and their differentiation to cardiomyocytes. The possible signals and cues involved in the commitment and early differentiation of cardiomyocytes in this model will be discussed as well as the molecular, structural and electrophysiologic characteristics of the generated hESC-derived cardiomyocytes. Finally, the hurdles and challenges toward fully harnessing the potential clinical applications of these unique cells will be described.

The ubiquitin-proteasome pathway has a central role in selective degradation of intracellular proteins. Among the key proteins degraded by the system are those involved in the control of inflammation, cell cycle regulation and gene expression. With numerous important cellular pathways affected, derangements in the ubiquitin system were shown to result in a variety of human diseases including malignancies, neurodegenerative diseases and hereditary syndromes, and proteasome inhibition was implicated as a potential treatment for cancer and inflammatory conditions. Two proteasome inhibitors are currently under clinical evaluation for multiple myeloma and acute ischemic stroke. The ubiquitin system also has an important function in the immune and inflammatory response. It is involved in antigen processing and presentation to cytotoxic T cells, and the activation of nuclear factor-kappa B – the central transcription factor of the immune system. Since the proteasome is the central source of antigenic peptides that are presented to the immune system, some viruses, such as the Epstein-Barr virus, developed escape mechanisms that manipulate the ubiquitin-proteasome system in order to persist in the infected host. Understanding the mechanisms underlying the production of viral antigens by the ubiquitin-proteasome system may have therapeutic applications such as future development of vaccines.