Biomedical subjects

Reuvit Halperin

Publications and source records attributed to Reuvit Halperin.

23 records · Page 2Linked to original sources

PubMed2002

Articular cartilage reconstruction using xenogeneic epiphyses slices.

Reconstruction of articular cartilage defects using adult osteochondral allografts is an established clinical procedure, whose principal drawback is lack of lateral integration of the grafts to the surrounding tissue. Autologous chondrocytes transplantation is a sophisticated technique requiring cell culture and a staged operation. Its main draw back is the lack of mechanical strength early on. This study was conducted in order to evaluate the possibility of using embryonal epiphyses as a cartilage reconstruction tissue. A xenogeneic human to rabbit sub-acute osteochondral defect model was designed to evaluate the possibility of allogeneic implantation in humans. The following procedures were perfomed (n = 5): transplantation of 1. live epiphyses 2. live epiphyses with autogeneic periosteum 3. de-vitalized epiphyses and 4. devitalized epiphyses with autogeneic articular chondrocytes. A fifth control group did not receive any implant. Animals in groups 1 and 2 had a viable reconstruction of the articular surface with little evidence of rejection and without pannus formation. Animals in groups 3 and 4 became severely arthritic and the graft was resorbed. Nitric oxide synthase accumulation was reduced in group 1 and 2 as compared to groups 3, 4, and 5, indicating a joint preserving function of the epiphyseal grafts. Epiphyseal grafts appear to be a feasible procedure for reconstruction of articular cartilage defects even in a xenogeneic model.

Journal Article↗

PubMed2002

Fetal survival in the rat as affected by intrauterine injection of serum containing antiphospholipid antibodies.

PROBLEM: We wanted to study and examine whether the detrimental effect of antiphospholipid antibodies on gestation is locally derived. Therefore, we established an experimental rat model, enabling to study the intrauterine effect of serum, containing antiphospholipid antibodies, in vivo. METHODS: Sera were obtained from five women, having anticardiolipin antibody and lupus anticoagulant, and presenting with antiphospholipid antibody syndrome. Pooled serum of 150 microL was injected into unilateral uterine horn of each rat on days L2-L7 of rat pregnancy. The contralateral uterine horn was used for injection of 150 microL normal serum or physiologic saline as a control. The rats were sacrificed on day L14, and the uterus of each rat was inspected for the presence of live and resorbed fetuses. RESULTS: A significant effect on fetal resorption and viability was observed following the intrauterine injection of antiphospholipid positive serum (APL positive serum), as compared with the intrauterine injection of normal serum or saline. A significant increase in fetal resorption rate and decrease in fetal viability was noted following the injection of APL positive serum on day L6 (P = 0.005 and 0.004, respectively) and day L7 (P = 0.003 and 0.003, respectively) as compared with normal serum. A comparison with the contralateral injection of saline demonstrated a significant effect of the APL positive serum also following the intrauterine injection on days L3 and L5. CONCLUSIONS: The current study provides an experimental rat model, which can be employed to study the local intrauterine effect of APL positive serum on pregnancy outcome and to further assess the efficacy of various treatment modalities.

Animals↗

PubMedDate not supplied

Apoptosis-related proteins (Fas, Fas ligand, bcl-2 and p53) in different types of human breast tumors.

The aim of this study was to evaluate the possible role of apoptosis-related proteins (ARP: Fas and Fas ligand, bcl-2, p53) in the progress of tumorigenesis in breast cancer. Epithelial tumor cells and lymphocytes were analyzed immunohistochemically for the rate of lymphoid infiltration and presence of ARP in 50 human breast tumors of different types. The tumors included: i) fibrocystic disease (n=12); ii) benign fibroadenoma (n=11); iii) carcinoma in situ (n=8); iv) invasive ductal carcinoma with high lymphoid infiltration (n=12); and v) invasive ductal carcinoma with lymphoid depletion (n=7). Both fibrocystic disease and fibroadenomas had low amounts of lymphocytes and very little lymphoid infiltration. In cancer in situ, expansion of lymphoid infiltrates and increased density of lymphocytes resulted in a rise in the total number of lymphocytes, reflecting intensification of the immune response. In carcinomas with high lymphoid infiltration, a significant increase in the number of Fas and FasL and p53-positive cells was found. The number of bcl-2-positive tumor cells in these tumors was not changed, whereas the number of bcl-2-positive lymphocytes decreased. In carcinomas with lymphoid depletion, the opposite picture was found as a result of deep subcompensation of the lymph system. ARP are present in a significantly higher number of lymphocytes than of the epithelial tumor cells. This indicates that the cells initiating apoptosis in tumors are themselves damaged by the process. The intense apoptosis in lymphocytes in malignant tumors may be one of the reasons for the progress of breast tumors.

Apoptosis↗

PubMedDate not supplied

The role of lymphocytes and macrophages in human breast tumorigenesis: an immunohistochemical and morphometric study.

The objective of the present study was to analyze the function of lymphoid elements in the tumorigenesis of human breast cancer, similar to their elucidation in human ovarian cancer in our previous work. The lymphocytic and macrophageal content of lymphocytes and macrophages was analyzed immunohistochemically and morphometrically in 49 human breast tumors of different types. The following types of tumors were studied: 1) fibrocystic disease, 2) fibroadenoma, 3) carcinoma in situ, 4) infiltrating ductal and lobular carcinoma with high lymphoid infiltration, and 5) infiltrating ductal and lobular carcinoma with lymphoid depletion. The first two had little lymphoid infiltration and few lymphocytes (mainly T cells), while carcinoma in situ had extensive lymphoid infiltration and increased lymphocytic density, the consequence of a sharp rise in total lymphocytes reflecting the intensified immune response. In ductal and lobular infiltrating carcinoma with high infiltration, T cells were in large excess of B cells (81% and 87% vs. 11%) and CD8+ lymphocytes were the predominant type of T cells (up to 90%), in both tumoral parenchyma and stroma. In infiltrating carcinoma with lymphoid depletion, the total lymphocyte and macrophage count and areas of lymphoid infiltrates decreased, relative to highly infiltrated carcinomas, as signs of deep subcompensation of the lymphoid system. The host's reaction to disease was reflected in high correlations between the densities of the lymphoid cellular elements as tumorigenesis evolved. We suggest that the stromal immunocompetent cells are a reservoir of T killers that eventually cross into the parenchyma and join T helpers and B lymphocytes in the immune antitumor response. In later stages of cancer the response is exhausted, as manifested in lymphoid subcompensation.

Breast Neoplasms↗

PubMedDate not supplied

Diagnostic hysteroscopy as a primary tool in a basic infertility workup.

OBJECTIVE: To assess the value of diagnostic hysteroscopy in a primary workup of infertility. METHODS: We performed a retrospective analysis (Canadian Task Force Classification II-2) of 221 infertile patients referred to the Outpatient Center for Uterine Cavity Evaluation and the Tel-Aviv University affiliated Assaf Harofe Medical Center for evaluation of the uterine cavity. Patients underwent a diagnostic office hysteroscopy. RESULTS: Hysteroscopy revealed an abnormal uterine cavity in 30% of women evaluated for either primary or secondary infertility. No significance was found regarding the total number of intrauterine pathologies when comparing the groups of primary versus secondary infertility. CONCLUSION: Routine diagnostic hysteroscopy should be part of an infertility workup in primary and secondary infertility.

Adolescent↗