Israel Medical Association Journal

Background: Genetic factors have been shown to play a major role in the development of peak bone mass, with hereditability accounting for about 50-85% of the variance in bone mass. Numerous candidate genes were proposed to be involved in osteoporosis, but the precise genes and their relative contribution remain unknown.

Objectives: To gain insight into the genetic basis of idiopathic low bone mineral density in Israeli patients by analyzing the impact of two candidate genes: polymorphism of the vitamin D receptor gene and polymorphism A986s in the calcium-sensing receptor gene.

Methods: We analyzed 86 Jewish Israeli patients with LBMD[1]: 38 premenopausal women and 48 men, and compared the allelic pattern distribution with that of the general population (126 men and 112 women). Genotyping of the VDR[2] gene was performed in three polymorphic sites using restriction enzymes, and allelic analysis of A986s polymorphism in the CaSR[3] gene was performed using the denaturing gradient gel electrophoresis technique.  

Reaults: In LBMD women the distributions of VDR alleres in Apal polymorphism were AA=7/28, Aa=16/28 and aa=5/28; in TaqI polymorphism TT=10/31, Tt=16/31 and tt=5/31; and in BsmI polymorphism BB=7/32, Bb=14/32 and 11/32. In LBMD men the distributions were AA=17/39, Aa=21/39 and aa=1/39; in TaqI polymorphism TT=12/42, Tt=23/42 and tt=7/42; and in BsmI polymorphism BB=12/41 Bb=18/41 and bb=11/41. The distributions of all these polymorphisms in the control groups were not significantly different. Adjusting for the independent age and gender parameters confirmed that these three polymorphisms of the VDR gene did not have a significant effect on bone mineral density. Thirty percent (24/79) of LBMD patients of either sex displayed heterozygosity of the CaSR A986s polymorphism, compared with 40 of 203 controls (19.7%) (P=0.059). Adjusting for age and gender in these patients revealed a significant difference in the femoral neck BMD[4] between homozygotes and heterozygotes (P=0.002). The age at menarche of the LBMD women was found to predict 61% of the variance of femoral neck BMD.

Conclusions: In Israeli Jewish men and premenopausal women VDR gene alleles do not seem to be associated with lower lumbar spine or femoral neck BMD. A trend towards heterozygosity for a CaSR polymorphism missense mutation was noted in the LBMD patients. Age at menarche in the LBMD women was found to be an important predictor of BMD. A significant difference was found between LBMD women and healthy control women towards heterozygosity for a CaSR polymorphism, as well between homozygotes and heterozygotes for a CaSR polymorphism in BMD. The significance of these findings and their applicability to a larger population awaits further studies.

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Background: Matrix metalloproteinases are proteolytic enzymes that degrade extracellular matrix components. Numerous studies have demonstrated that individual MMPs[1] play a crucial role in tumor invasion and metastasis.

Objective: To examine the expression of MMPs and their inhibitor TIMP-2 in neoplastic and normal thyroid tissues.

Methods: We examined 33 cases of thyroid tumor (papillary, follicular and medullary carcinoma, follicular adenoma and multinodular goiter). MMP protein content and activity were measured by enzyme-linked immunosorbent assay and gel zymography. Immunohistochemistry was also performed.

Results: The thyroid tissues examined secreted MMP-2 and 9 as well as TIMP-2, but only MMP-2 was significantly higher in papillary carcinoma cases compared to the adjacent normal tissue or to the other tumor entities. Increased MMP-2 immunohistochemical staining was demonstrated in the neoplastic papillary epithelial component. No significant difference was seen between papillary carcinomas with lymph node metastases and those without.

Conclusions: Increased MMP-2 expression may be useful as a diagnostic marker to differentiate papillary carcinoma from other thyroid neoplasms, but it cannot serve as a useful prognostic marker.

Southern Sinai, a mountainous desolated arid area, is inhabited by Bedouin nomad tribes composed of Arabic-speaking Moslems. Until the Six Day War between Egypt and Israel in 1967, healthcare services in the region were based on traditional medicine performed by the Darvish, a local healer. Over the course of Israeli rule (1967-1982) an elaborate healthcare service was established and maintained, providing modern, up to date, comprehensive medical services that were available to all free of charge.

Background: Recent years have brought significant progress to the development of hormonal therapies for the treatment of breast cancer. Several new agents have been approved for the treatment of breast cancer in the metastatic setting, among which is the new non-steroidal aromatase inhibitor, anastrozole, introduced for clinical use in Israel in March 1997.

Objectives: To evaluate the response rate and survival duration of patients treated with anastrozole for metastatic breast cancer, who had previously received at least one line of hormonal therapy.

Methods: Anastrozole was administered to 37 patients with metastatic breast cancer. The median age was 64 years. Estrogen receptor was positive in 20 patients, negative in 10 and unknown in 7. All patients were previously treated with tamoxifen in the adjuvant setting or as first-line hormonal therapy for metastatic disease. Anastrozole was given orally, 1 mg/day. Response was evaluated 2 months after the initiation of treatment and reevaluated every 2 months. Therapy was given until disease progression. Ten ER[1]-negative patients were excluded from the final analysis.

Results: Twenty-seven patients were eligible for response and toxicity analysis. The median follow-up was 20 months. One patient (3.7%) achieved complete response and remains free of disease 28 months after start of therapy. No partial responses were seen. Twenty patients (74%) had stable disease. Two year actuarial survival was 57%. Median survival was 26.5 months after starting therapy and median progression free survival was 11 months. The toxicity was mild: one patient (3.7%) complained of weight gain and one patient (3.7%) had mild fatigue.

Conclusion: Although the response rate was low, hormonal therapy with anastrozole seems to be beneficial in terms of disease stabilization, freedom from progression, and overall survival without serious toxicity.  

Recent data have shed significant new light on the structural and functional development of the kidneys, as well as on a rare congenital form of bilateral renal hypoplasia called congenital oligomeganephronia. In this renal disorder, few greatly enlarged and hard-working nephrons are found that will ultimately sclerose and lead to end-stage renal failure during early childhood. At the same time it has been recognized that the number of nephrons in the kidneys of various animal species and humans is correlated to renal mass. Therefore, premature babies and/or infants small for gestational age due to intrauterine malnutrition will be born with relatively small kidneys and a certain nephron deficit, a condition called congenital oligonephropathy. Extensive worldwide epidemiologic studies have now shown that these premature or SGA[1] infants have a high incidence of cardiovascular disease, hypertension, hyperlipidemia, diabetes and renal failure in adulthood. Although the pathophysiologic mechanisms responsible for these complications of premature birth are not entirely understood, it has become clear that the described association may pose a possible health problem in the adult population. This review describes the background of COMN[2] and CON[3] as well as the evidence that has accumulated on the adult complications of the latter. In addition, some thoughts are presented on the importance of identifying subjects possibly affected by CON, such that early recognition may alter the ultimate outcome.

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Background: Leptin is a 16 kDa hormone synthesized by adipocytes and involved in body weight regulation.

Objectives: To determine serum leptin concentrations in heart, liver and kidney transplant recipients.

Methods: We investigated 57 patients: 18 male heart transplant recipients (age 25-69 years) at 1-66 months after transplantation, 6 female and 8 male liver transplant recipients (age 33-70) at 11-73 months after transplantation, and 10 female and 15 male kidney transplant recipients (age 20-61) at 3-138 months after transplantation. All recipients were receiving immunosuppressive therapy, including prednisone 0-20 mg/day, azathioprine 75-125 mg/day, cyclosporin 100-250 mg/day or tacrolimus 2-10 mg/day. The results were compared to those of 10 female and 10 male healthy controls. Morning serum concentrations of leptin were measured with a commercial radioimmunoassay (Linco Research Inc., USA), and serum insulin and cortisol levels were measured by radioimmunoassay.

Results: Patients (both men and women) after heart, liver and kidney transplantation exhibited significantly higher serum concentrations of leptin and leptin/body mass index ratios than controls. Serum leptin concentrations were significantly higher in women than in men and correlated very significantly with BMI[1] in all cases. The multivariate stepwise analyses showed that among parameters including BMI, gender, age, time after transplantation, prednisone dose, hematocrit, serum concentrations of glucose, albumin, creatinine, cortisol and insulin, only BMI, gender, cortisol and insulin were significant independent determinants of serum leptin levels in these patients.

Conclusions: This is the first report showing that, in addition to body mass index and gender, basal cortisol and insulin levels affect the hyperleptinemia in transplant patients. The clinical relevance of hyperleptinemia in these patients will require further investigation.

Severe combined immunodeficiencies represent a heterogeneous group of hereditary defects of the immune system that affect both T and B cells and whose etiology has only recently begun to be understood. A portion of these SCID patients bear a defect in either of the two recombination-activating genes, Rag-1 or Rag-2, while others have mutations in a newly identified gene, Artemis. Omenn syndrome is an unusual severe immunodeficiency with T cells but no B cells, and peculiar features also due to a defect in Rag-1 or Rag-2 genes. All these three forms are characterized by an impairment of the VDJ recombination, the process that insures the somatic diversification of immunoglobulin and T cell receptor-encoding genes. Recent findings have enabled us to better understand the pathophysiology of these three immunodeficiencies, which affect the V(D)J recombination process to a different extent and in different ways.

The notion of health used in medicine may have important implications, such as guiding the allocation of medical resources. This paper explores the notion of health through an overview and conceptual analysis of various notions of health found in modern medical and the philosophical literature. It argues that health is characterized either positively or negatively (per exclusion), and either mechanistically (as the set of common or ideal states of a species) or holistically (as unimpaired self-organization of organisms). The paper concludes that a sound notion of health characterizes health negatively and holistically, assimilating mechanism as a good approximation in simple cases.

Background: The Bloom syndrome gene, BLM, was mapped to 15q26.1 and its product was found to encode a RecQ DNA helicase. The Fanconi anemia complementation group C gene was mapped to chromosome 9q22.3, but its product function is not sufficiently clear. Both are recessive disorders associated with an elevated predisposition to cancer due to genomic instability. A single predominant mutation of each disorder was reported in Ashkenazi Jews: 2281delATCTGAinsTAGATTC for Bloom syndrome (BLM-ASH) and IVS4+4A®T for Fanconi anemia complementation group C.

Objectives: To provide additional verification of the mutation rate of BLM and FACC[1] in unselected Ashkenazi and non-Ashkenazi populations analyzed at the Sheba Medical Center, and to trace the origin of each mutation.

Methods: We used polymerase chain reaction to identify mutations of the relevant genomic fragments, restriction analysis and gel electrophoresis. We then applied the Pronto^TM kit to verify the results in 244 samples and there was an excellent match.

Results: A heterozygote frequency of 1:111 for BLM-ASH and 1:92 for FACC was detected in more than 4,000 participants, none of whom reported a family history of the disorders. The Pronto^TM kit confirmed all heterozygotes. Neither of the mutations was detected in 950 anonymous non-Ashkenazi Jews. The distribution pattern of parental origin differed significantly between the two carrier groups, as well as between each one and the general population.

Conclusions: These findings as well as the absence of the mutations in non-Ashkenazi Jews suggest that: a) the mutations originated in the Israelite population that was exiled from Palestine by the Roman Empire in 70 AD and settled in Europe (Ashkenazi), in contrast to those who remained; and b) the difference in origin distribution of the BS[2] and FACC mutations can be explained by either a secondary migration of a subgroup with a subsequent genetic drift, or a separate geographic region of introduction for each mutation.

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[1] FACC = Fanconi anemia complementation group C