The lethal poisoning of Alexander Litvinenco with the radioactive element polonium-210, and the risk that many civilians (including Israeli citizens) who were in the same location in London at the same time were exposed to radiation, was an unprecedented event in the western world. This was only the second known death due to ²¹⁰Po[1], a natural alpha radiation-emitting element. A task team was created to handle the event. The team comprised representatives from the Ministry of Health's advisory committee for radiological events (which includes the Israel Defense Force, the Israeli Atomic Energy Commission and the Ministry of Environmental Protection), the Public Health Services Central District, and a public relations expert. Forty-seven people were located and underwent an epidemiological inquiry, and urine samples for detection of ²¹⁰Po were sent abroad to a specialized laboratory. The radiotoxicological results were analyzed and evaluated by the expert team and follow-up recommendations were made. This unfamiliar and potentially stressful scenario was handled successfully by a multi-organizational multidisciplinary task team. The joint work of the task team was a real-life "exercise" simulating a radiological event in Israel. This team has recommended further evaluation of various vital missions in the event of any possible future radiological event, with special emphasis on a proactive communication approach to the media and the public.

Background: Syncope is a common clinical problem that often remains undiagnosed despite extensive and expensive diagnostic evaluation.

Objectives: To assess the diagnostic evaluation, costs and prognosis of patients hospitalized for syncope in a tertiary referral center according to discharge diagnosis.

Methods: We retrospectively reviewed the medical records of patients with a diagnosis of syncope discharged from a tertiary referral center in 1999. In addition, mortality data were obtained retrospectively a year after discharge for each patient.

Results: The study group comprised 376 patients. Discharge etiologies were as follows: vasovagal 26.6%, cardiac 17.3%, neurological 4.3%, metabolic 0.5%, unexplained 47.3%, and other 4%. A total of 345 patients were admitted to the internal medicine department, 28 to the intensive cardiac care unit, and 3 to the neurology department. Cardiac and neurological tests were performed more often than other tests, with a higher yield in patients with cardiac and neurological etiologies respectively. The mean evaluation cost was 11,210 ± 8133 shekels, and was higher in the ICCU[1] than in internal medicine wards (19,210 ± 11,855 vs. 10,443 ± 7314 shekels, respectively; P = 0.0015). Mean in-hospital stay was 4.9 ± 4.2 days, which was longer in the ICCU than in medicine wards (7.2 ± 5.6 vs. 4.6 ± 3.5 days, respectively; P = 0.024). Short-term mortality rates (30 days after discharge) and long-term mortality rates (1 year after discharge) were 1.9% and 8.8% respectively, and differed according to discharge etiology. LTM[2] rates were significantly higher in patients discharged with cardiac, neurological and unknown etiologies (not for vasovagal), compared with the general population of Israel (1 year mortality rate for the age-adjusted [65 years] general population = 2.2%). The LTM rate was higher in patients discharged with a cardiac etiology than in those with a non-cardiac etiology (15.4% vs. 7.4%, P = 0.04). Higher short and long-term mortality rates were associated with higher evaluation costs.

Conclusions: Hospitalization in a tertiary referral center for syncope is associated with increased mortality for most etiologies (except vasovagal), cardiac more than non-cardiac. Despite high costs of inpatient evaluation, associated with more diagnostic tests, longer in-hospital stay and higher mortality rates, nearly half of the patients were discharged undiagnosed. Outpatient evaluation should be considered when medically possible.

Background: Standard CD44 and its alternatively spliced variants were found to be associated with the metastatic potential of tumor cells and with cell migration of autoimmune inflammatory cells, including cells involved in experimental insulin-dependent diabetes mellitus.

Objectives: To investigate whether induction of anti-CD44 immune reactivity, through cDNA vaccination, could attenuate IDDM[1] in a transfer model of NOD mice.

Methods: Our vaccination technique involved the insertion of CD44s[2] or CD44v[3] cDNA into a silicone tube filled with a 2.5 cm long segment of hydroxylated-polyvinyl acetate wound dressing sponge (forming a virtual lymph node) which was implanted under the skin of male NOD recipients reconstituted with diabetogenic spleen cells of female NOD donors. The VLN[4] were implanted 20 days before and 3 days after cell transfer.

Results: In contrast to control groups of recipient mice, recipients vaccinated with VLN loaded with CD44v or CD44s cDNAs developed resistance to IDDM almost to the same extent. Our results suggest that the gene vaccination effect was mediated by anti-CD44 antibody rather than by cellular immunity. Histopathological examinations revealed a significant protection of pancreatic islets in the DNA-vaccinated recipients, whereas the islets of control recipients of diabetogenic cells were almost totally destroyed.

Conclusions: These findings may open new opportunities for IDDM therapy in the future.

Background: The presence of anti-cyclic citrullinated peptide autoantibody is highly specific for rheumatoid arthritis. Certain HLA-DR4 (HLA-DRB1*04) alleles, also known as the "shared epitope," are associated with increased susceptibility to RA[1]. In addition, these alleles may also have relevance for disease outcome. Anti-CCP[2] antibody positivity has been associated with the presence of HLA-DR4 alleles in patients with RA. However, there is little information available regarding any relationship between quantitative anti-CCP production (serum anti-CCP concentrations) and the shared epitope.

Objectives: To determine the association between anti-CCP antibody production and various HLA-DRB1 alleles.

Methods: Serum anti-CCP, rheumatoid factor and C-reactive protein levels were assessed in 53 RA patients. All these patients underwent HLA-DRB1 genotyping.

Results: Of the 53 patients 33 (62%) were positive for anti-CCP antibody. We found significant correlations between anti-CCP and RF[3] positivity (chi-square = 6.717, P < 0.01), as well as between anti-CCP and HLA-DRB1*04 positivity (chi-square = 5.828, P < 0.01). There was no correlation between RF positivity and serum levels, CRP[4] serum levels and HLA-DRB1*04 positivity. When quantitatively comparing serum anti-CCP levels with shared epitope positivity, patients carrying one or two copies of HLA-DRB1*04 alleles had significantly higher anti-CCP concentrations (530.0 ± 182.6 U/ml) compared to DRB1*04-negative patients (56.8 ± 27.4 U/ml) (P < 0.01). There was no difference in serum anti-CCP antibody concentrations between patients carrying only one HLA-DRB1*01 allele but no HLA-DRB1*04 allele (12.0 ± 8.6 U/ml) in comparison to SE[5]-negative patients (76.8 ± 56.2 U/ml). Regarding non-SE HLA-DRB1 genotypes, all 6 patients (100%) carrying DRB1*15 alleles and 6 of 7 (85%) patients carrying DRB1*13 were anti-CCP positive. In addition, patients with HLA-DRB1*13 (282.5 ± 23.8 U/ml) and DRB1*15 (398.7 ± 76.2 U/ml) produced significantly more anti-CCP than did any other non-SE HLA-DRB1 subtypes (P < 0.01).

Conclusions: There is significant association between anti-CCP and RF, as well as between anti-CCP and SE positivity in RA. In addition, the presence of one or two copies of HLA-DRB1*04 alleles has been associated with higher serum anti-CCP antibody levels. Thus, patients carrying HLA-DRB1*04 alleles exhibited an overall tenfold increase in serum anti-CCP antibody levels in comparison to HLA-DRB1*04-negative subjects. Increased anti-CCP production may also be associated with other non-SE HLA-DRB1 genotypes, such as DRB1*13 or DRB1*15. In reports by other investigators, both anti-CCP concentrations

The antiphospholipid syndrome is characterized by recurrent fetal loss, venous and/or arterial thrombosis, and thrombocytopenia associated with elevated titers of lupus anticoagulant and anticardiolipin antibodies. Although thrombosis is the characteristic vascular involvement in APS[1], the development of vascular aneurysms in patients with APS has been reported. We describe four patients with established APS, who developed abdominal aortic aneurysm, and review the literature on previous published cases of arterial aneurysms developing in patients with APS. In addition, we discuss the possible pathophysiological association between APS and the development of this vascular abnormality.

The most troublesome complication of acute pericarditis is recurrent episodes of pericardial inflammation, which occur in 15–32% of cases. It was recently found that viral infection has a major role, but in many cases the cause is unknown. The optimal method for prevention has not been fully established; accepted modalities include non-steroidal anti-inflammatory drugs, corticosteroids, immunosuppressive agents, and pericardiectomy. Based on the proven efficacy of colchicine in familial Mediterranean fever, several small and large-scale international clinical trials have shown the beneficial effect of colchicine therapy in preventing recurrent pericarditis. Indeed, colchicines-treated patients consistently display significantly fewer recurrences, longer symptom-free periods, and even when attacks occur they are weaker and shorter in nature. It was also found that pretreatment with corticosteroids substantially attenuates the efficacy of colchicine, as evidenced by significantly more recurrences and longer therapy periods. Colchicine is a safe and effective modality for the treatment and prevention of recurrent pericarditis, especially as an adjunct to other modalities, since it provides a sustained benefit superior to all current modalities. The safety profile seems superior to other drugs such as corticosteroids and immunosuppressive drugs.

Chronic fatigue syndrome is a heterogeneous disorder with unknown pathogenesis and etiology, characterized by disabling fatigue, difficulty in concentration and memory, and concomitant skeletal and muscular pain. Several mechanisms have been suggested to play a role in CFS[1], such as excessive oxidative stress following exertion, immune imbalance characterized by decreased natural killer cell and macrophage activity, immunoglobulin G subclass deficiencies (IgG-1[2], IgG-3) and decreased serum concentrations of complement component. Autoantibodies were also suggested as a possible factor in the pathogenesis of CFS. Recent studies indicate that anti-serotonin, anti-microtubule-associated protein 2 and anti-muscarinic cholinergic receptor 1 may play a role in the pathogenesis of CFS. It has been demonstrated that impairment in vasoactive neuropeptide metabolism may explain the CFS symptoms

Treatment of vasculitides has progressed markedly over the past few decades. Recent therapeutic strategies in severe and refractory anti-neutrophil cytoplasmic antibodies-associated vasculitides include immunomodulating methods (e.g., plasma exchanges), products (such as intravenous immunoglobulins) and, more recently, new agents called biotherapies. Some of them (e.g., anti-tumor necrosis factor-alpha and anti-CD20 monoclonal antibodies) have achieved promising results and are now often used to treat severe cases.

Background: In the course of occurrence of cerebral infarction, cerebral hemorrhage and subarachnoidal hemorrhage episodes, periodicities resembling those found in the solar and geomagnetic activity were found by Kováč and Mikulecký (2005).

Objectives: To investigate putative relationships between two indices of solar activity and one index of geomagnetic activity on one side and the occurrence of cerebral infarction on the other.

Methods: In addition to the 192 monthly cases out of 6100 new cases of cerebral infarction that occurred between January 1989 and December 2004, monthly averages for Wolf numbers, solar flares index and Ap index were included in the analysis. The cross-correlation between each cosmo-geophysical variable on the one hand and the number of new cases of the disease on the other was computed. The quadratic regression with the chosen time delay was also studied using, separately, the Wolf numbers, solar flares and Ap index as the explanatory variable and the number of cases of cerebral infarction as the responding variable.

Results: Significantly negative correlation coefficients between the monthly means of the Wolf numbers, of solar flares and of Ap index on the one hand and monthly numbers of new cases of the disease on the other were found for the delays between -6 and +17 months. The cross-regression results for the delay of +5 months (infarction delayed after each cosmo-geophysical variable by 5 months) displayed a linear decrease except for the Wolf numbers where the parabolic decrease of cases was significant.

Conclusions: An increased intensity of the studied cosmo-geophysical parameters appears to be significantly connected with decreased occurrence of cerebral infarctions, and vice versa. This effect seems to last up to 17 months. The results are supported by a few similar findings in the literature. Putative cosmo-biomedical connections warrant further study to verify them in larger samples and longer time scales. If confirmed, their mechanisms should be elucidated.