Israel Medical Association Journal

Background: The co-morbidity of human immunodeficiency virus and other sexually transmitted diseases in Israel has not been established. 

Objectives: To compare the prevalence of STDs [1]among HIV[2]-positive patients to HIV-negative patients visiting an STD clinic in northern Israel. 

Methods: Between December 2000 and December 2001, 176 HIV-positive individuals (53% males) were screened and compared to 200 HIV-seronegative individuals (76% males). Demographics, symptomatology and risk factors were obtained via questionnaire. First-void urine samples were tested for the detection of Chlamydia trachomatis and Neisseria gonorrhoeae. Serum was tested for type-specific herpes simplex virus-2, hepatitis B and syphilis. 

Results: Relative to the seronegative STD patients, HIV-positive patients exhibited significantly greater risk-reducing sexual behaviors such as consistent condom use [29/86 (33.7%) vs. 16/187 (8.6%), P < 0.001], and abstinence in the previous 6 months [43/125 (34%) vs. 7/185 (3.8%), P < 0.001]. Nevertheless, STD prevalence was higher among HIV-positive than HIV-negative patients (79.5% vs. 37.5%, P < 0.001). HSV[3]-2, syphilis and HBV[4] were more common among HIV-positive than HIV-negative patients [120/175 (68.8%)] vs. 18/200 (9%), P < 0.001)], [43/161 (26.7%) vs. 0%, P < 0.001)], [13/171 (7.6%) vs. 3/200 (1.5%), P < 0.01)], respectively. In contrast, Chlamydia and gonorrhea were more commonly found in HIV-negative patients than HIV-positive patients [3/176 (1.7%) vs.13/200 (6.5%), P < 0.05] vs. [0% vs.5/200 (2.5%), P < 0.05], respectively. 

Conclusion: Despite the low risk sexual behavior of Israeli HIV patients, they had a high prevalence of chronic STDs (e.g., HSV-2, HBV and syphilis). The lower prevalence of Chlamydia and gonorrhea among HIV-immunosuppressed patients may be attributed to routine antibiotic prophylaxis against opportunistic infections. Nevertheless, as advocated by international health organizations, it appears prudent to recommend the routine screening of these asymptomatic HIV-positive patients for STD pathogens. 

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.

Human embryonic stem cells may serve as a potentially endeless source of  transplantable cells to treat various neurologic disorders. Accumulating data have shown the therapeutic value of various neural precursor cell types in experimental models of neurologic diseases. Tailoring cell therapy for specific disorders requires the generation of cells that are committed to specific neural lineages. To this end, protocols have been developed recently for the derivation of dopaminergic neurons, spinal motor neurons and oligodendrocytes from hESC[1]. These protocols recapitulate normal development in culture conditions. However, a novel concept emerging from these studies is that the beneficial effect of transplanted stem cells is not only via cell replacement in damaged host tissue, but also by trophic and protective effects, as well as by an immunomodulatory effect that down-regulates detrimental brain inflammation.

Objective: To determine breast-feeding patterns and the association between sociodemographic characteristics and breast-feeding in the Tel Aviv district.

Methods: The mothers of infants aged 2, 4, 6 and 12 months, attending 59 well-baby clinics in the Tel Aviv district, were interviewed by telephone. Singleton infants who weighed less than 2,000 g and multiple-gestation infants were excluded from the study. The questions covered background data, sociodemographic characteristics of the family, and breast-feeding practices. Stepwise logistic regression was used to analyze the association between breast-feeding and various sociodemographic characteristics.

Results: Altogether, 78.5% of the mothers (1,307/1,665) initiated breast-feeding. The rate of breast-feeding at 2, 4, 6 and 12 months was 55.8, 36.8, 29.9 and 11.8%, respectively. Only 35.8% of the infants at 2 months and 11.2% at 6 months were exclusively breast-fed. The mean duration of breast-feeding was 5.2 ± 0.2 months. Grand multiparas (≥5 children) had a significantly higher rate of breast-feeding than women with one to four children (P < 0.001). More likely to breast-feed for 2 weeks or longer were women married to Yeshiva students (odds ratio = 5.3), women with ≥13 years education (OR[1] = 2.1), and women on maternity leave (OR = 1.6). The predictors for breast-feeding for 6 months or longer were similar.

Conclusions: Although the rate of breast-feeding initiation in central Israel was 78.5%, only 29.9% of the mothers continue to breast-feed for 6 months. Already at a young age, an appreciable number of breast-fed infants receive infant formula. Breast-feeding promotion should focus on less educated women, homemakers, and families with one to four children.

Background: Visceral leishmaniasis was first reported in Israel (then Palestine) in 1929. In the 1960s and 1970s, it was endemic to northern Israel, but only partial data about the disease have been gathered since then.

Objective: To investigate the epidemiologic trends of visceral leishmaniasis in Israel from 1960 to 2000, and to delineate some clinical features of the infection.

Methods: Data were collected from hospital charts, scientific publications, and reports of the Ministry of Health and the Kuvin Center for the Study of Infectious and Tropical Diseases.

Results: During the last four decades, 87 cases of visceral leishmaniasis were diagnosed in Israel, 76 of them (87%) in children. All 54 patients diagnosed in the 1960s occurred in the northern part of the country. The rate of infection declined significantly in the 1970s (5 cases) and then increased slightly in the 1980s (11 cases) and 1990s (17 cases). More than 50% of the cases in the 1990s were in central Israel. Children accounted for 100% of cases in the 1960s but only 58% in the 1990s. The main clinical features of the patients diagnosed in the last decade were fever, weight loss, hepatosplenomegaly and pancytopenia. Three of the adults were co-infected with human immunodeficiency virus.

Discussion: The decline in the incidence of visceral leishmaniasis in the 1970s and the slight increase in the 1980s and 1990s can be attributed to changes in the animal reservoir and vectors, and in the immunity status of part of the population exposed to Leishmania.

Conclusions: Visceral leishmaniasis has reemerged in Israel. This mandates better control of the animal reservoir and vectors and increased awareness of this infection.

Background: The humanized SCID mouse model is an attractive tool for testing gene therapy to combat human immunodeficiency virus infection in vivo.

Objectives: To devise a more specific gene therapy directed against HIV, replacing the formerly used interferon with either soluble CD4 molecule immunoadhesin (sCD4-IgG) and/or anti-gp41 monoclonal antibody (2F5), or negative transdominants (Tat, Rev).

Methods: Human monocytoid cell line (U937) was transfected with IFNa[1], b or g genes. 3T3 murine fibroblastic cell line was transfected with sCD4-IgG or 2F5, or both genes, and a human T4 cell line (CEM) was grafted to SCID mice. Negative transdominant genes (Tat, Rev or both) were also transduced in CEM T cell line. Animals were then challenged with HIV-1[2]. Viral load was followed.

Results: IFNa or b were potent anti-HIV, reducing viral load in vivo and inhibiting reverse transcriptase activity in human-removed cells from animals. sCD4-IgG immunoadhesin and gp41 monoclonal antibody resulted in a dramatic reduction of HIV-1 cellular and plasmatic viral load in humanized SCID mice. The simultaneous introduction of negative Tat and Rev genes resulted in a synergistic inhibition of HIV-1 replication in vivo.

Conclusions: Despite the marked reduction of HIV-1 propagation by IFN genes or by negative Tat and Rev transdominants, the gene therapy using soluble CD4 immunoadhesin or anti-gp41 was a more efficient preventive treatment against HIV infection.

Only one case of a cow infected with bovine spongiform encephalopathy has been reported in Israel. Its publication, in 2002, caused both public and professional concern. The inevitable health policy question raised was whether or not to recommend against consuming beef and what public health measures should be taken. In this article we describe the prion diseases among animals and humans, their interaction and the precautionary procedures that were carried out by the state Veterinary Services and the Ministry of Health since 1988. The BSE[1] case (a 10 year old dairy cow) is believed to be the result of local consumption of infected food with mammalian meat and bone meal more than a decade earlier. The risk assessment took into consideration that no cases of vCJD (a new variant of Creutzfeldt-Jacob disease) have ever been diagnosed in Israel, as well as the low risk of contamination of the meat due to the religious method of slaughtering performed in the country. The policy decision was to implement a contingency plan prepared in advance. Israel was reclassified from the level II category of geographic risk where BSE is unlikely but not excluded in the herds, to level III, where BSE is likely but not confirmed, or confirmed at a lower level. No undue damage to the meat industry has occurred. By the end of 2002, despite the examination of more than 3,800 brains from slaughtered cows older than 3 years, no other cases of BSE have been detected.

Background: Experimental and clinical protocols are being developed for the cryopreservation of human hematopoietic progenitor cells. However, the effect of these procedures on the potential for HPC[1] to repopulate bone marrow is unknown.

Objectives: To examine the effect of cryopreservation on the ability of fetal human liver HPC, which include CD34+ cells and long-term culture-initiating cells, to repopulate immunodeficient non-obese diabetic/severe combined immunodeficiency mouse bone marrow.

Methods: Groups of sublethally irradiated NOD[2]/SCID[3] mice were injected intravenously with cryopreserved or freshly isolated fetal human liver HPC.

Results: Seven weeks after transplantation, flow cytometric analysis of bone marrow samples showed that mice that received the transplanted cells (either cryopreserved or freshly isolated) demonstrated both lymphoid and myeloid differentiation as well as the retention of a significant fraction of CD34+ cells. Conclusions: Cryopreserved fetal human liver-derived HPC appear to be capable of initiating human cell engraftment in NOD/SCID mouse bone marrow and open the possibility of using cryopreserved fetal human liver HPC for gene manipulation, gene transfusion therapy, and transplantation purposes.

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[1] HPC = hematopoietic progenitor cells

[2] NOD = non-obese diabetic

[3] SCID = severe combined immunodeficiency

Background: Decreased heparan sulfate proteoglycan content of the glomerular basement membrane has been described in proteinuric patients with diabetic nephropathy. Heparanase is an endo-b-D-glucuronidase that cleaves negatively charged heparan sulfate side chains in the basement membrane and extracellular matrix.

Objectives: To investigate whether urine from type I diabetic patients differs in heparanase activity from control subjects and whether resident glomerular cells could be the source of urinary heparanase.

Methods: Using soluble ³⁵S-HSPG[1] and sulfate-labeled extracellular matrix we assessed heparanase activity in human glomerular epithelial cells, rat mesangial cells, and urine from 73 type I diabetic patients. Heparanase activity resulted in the conversion of a high molecular weight sulfate-labeled HSPG into heparan sulfate degradation fragments as determined by gel filtration analysis.

Results: High heparanase activity was found in lysates of both epithelial and mesangial cells. Immunohistochemical staining localized the heparanase protein to both glomeruli capillaries and tubular epithelium. Heparanase activity was detected in the urine of 16% and 25% of the normoalbuminuric and microalbuminuric diabetic patients, respectively. Urine from 40 healthy individuals did not posses detectable heparanase. Urinary heparanase activity was associated with worse glycemic control.

Conclusion: We suggest that heparanase enzyme participates in the turnover of glomerular HSPG. Hyperglycemia enhances heparanase activity and/or secretion in some diabetic patients, resulting in the loss of albumin permselective properties of the GBM[2].

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[1] HSPG = heparan sulfate proteoglycan

[2] GBM = glomerular basement membrane