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1.
2.
Efrat Rorman Chen Stein Zamir Irena Rilkis Hilla Ben-David 《Reproductive toxicology (Elmsford, N.Y.)》2006,21(4):458
Toxoplasma gondii (T. gondii) is the cause of toxoplasmosis. Primary infection in an immunocompetent person is usually asymptomatic. Serological surveys demonstrate that world-wide exposure to T. gondii is high (30% in US and 50–80% in Europe). Vertical transmission from a recently infected pregnant woman to her fetus may lead to congenital toxoplasmosis. The risk of such transmission increases as primary maternal infection occurs later in pregnancy. However, consequences for the fetus are more severe with transmission closer to conception. The timing of maternal primary infection is, therefore, critically linked to the clinical manifestations of the infection. Fetal infection may result in natural abortion. Often, no apparent symptoms are observed at birth and complications develop only later in life. The laboratory methods of assessing fetal risk of T. gondii infection are serology and direct tests.Screening programs for women at childbearing age or of the newborn, as well as education of the public regarding infection prevention, proved to be cost-effective and reduce the rate of infection.The impact of antiparasytic therapy on vertical transmission from mother to fetus is still controversial. However, specific therapy is recommended to be initiated as soon as infection is diagnosed. 相似文献
3.
Leon Ardekian Efrat Oved-Peleg Eli E Mactei Micha Peled 《Journal of oral and maxillofacial surgery》2006,64(2):277-282
PURPOSE: Augmentation of the maxillary sinus floor is a well-documented technique and is generally accepted as a pure implantology procedure to facilitate placement of dental implants in the posterior atrophic maxilla. The objective of this report was to evaluate the significance of the sinus membrane perforations on the incidence, complications, and success rate of this procedure. PATIENTS AND METHODS: Patients who received sinus floor augmentation and simultaneous placement of dental implant were included in this study. Subgroup I consisted of patients who had their sinus membrane perforated and repaired during the procedure with resorbable membrane. Subgroup II consisted of patients whose Schneiderian membrane was not perforated during the procedure. The patients were followed between 1 to 4 years after augmentation. RESULTS: All perforations were classified as class II or III. The success rate of the implants in the perforation group was 94.4%, and that for the nonperforation group was 93.9%. The difference between the 2 study groups was statistically not significant. A significant statistical correlation was found between the residual ridge height and the membrane perforation (P < .01). CONCLUSIONS: Mainly due to technical difficulties, maxillary sinus membrane perforation occurs more frequently with a small height of residual alveolar bone. In this study, no statistical difference was observed in the success rate of the immediate implants placed with sinus bone grafting in patients whose membrane was perforated versus those patients in whom an intact membrane was maintained. 相似文献
4.
5.
Sexual dimorphism of pancreatic beta-cell degeneration in transgenic mice expressing an insulin-ras hybrid gene 总被引:3,自引:0,他引:3
S Efrat 《Endocrinology》1991,128(2):897-901
The human H-ras oncogene induces cell degeneration and diabetes when expressed in pancreatic beta-cells in transgenic mice. The disease develops predominantly in male mice between 5-8 months of age. Most transgenic female mice do not manifest this phenotype, even at much greater ages. However, ovariectomy induces female beta-cell degeneration similar to that in the males. In contrast, castration or the presence of the testicular feminization mutation do not alter the course of the disease in males. Treatment of males and ovariectomized females with estrogen prevents the development of diabetes. These results suggest that testicular androgens and a functional testosterone receptor are not required for the increased susceptibility of male beta-cells to the effects of the Ras oncoprotein, and that the relative resistance of female beta-cells is mediated by estrogen. In addition, a genetic component of female beta-cell resistance to Ras is revealed by crossing the transgenic mice with C3HeB/FeJ mice, which results in a pronounced increase in the incidence of female diabetes. 相似文献
6.
Apoptotic defects and impaired clearance of cellular debris are considered key events in the development of autoimmunity,
as they can contribute to autoantigen overload, and may initiate an autoimmune response. The pentraxins are a group of highly
conserved proteins including the short pentraxins, C-reactive protein (CRP) and serum amyloid-P (SAP), and the long pentraxin-3
(PTX3), which are all involved in innate immunity and in acute-phase responses. Mannan-binding lectin (MBL) is an activator
of the complement system, and Apolipoprotein A-1 (Apo A-1) is pivotal in the cholesterol homeostasis and has anti-inflammatory
properties. In addition to their role in innate immunity and inflammation, each of these five proteins participates in the
removal of damaged and apoptotic cells. In this review, we discuss the clinical significance of different levels of these
proteins, their role in the induction or protection from autoimmunity, and the presence of specific autoantibodies against
them in the different autoimmune diseases. 相似文献
7.
Margalith M Chatlynne LG Fuchs E Owen C Lee CR Yermiyahu T Whitman JE Ablashi DV 《Journal of acquired immune deficiency syndromes (1999)》2003,34(5):500-505
OBJECTIVE: To compare the prevalence of antibodies to human herpesvirus 8 (HHV-8) or Kaposi sarcoma-associated herpesvirus among Israeli and Ethiopian subjects. METHODS: Serum samples were obtained from 98 Israeli Jewish students aged 18-30 years, 100 HIV-1-seronegative Ethiopian immigrants to Israel of the same age, and 100 HIV-1-seronegative Ethiopian children 1-12 years old upon their arrival in southern Israel. Plasma samples were obtained from 3 hospitalized patients with multicentric Castleman disease (MCD) as positive controls. All serum samples were tested for antibodies to both latent and lytic antigens. Antibodies to the lytic antigens and the latency-associated nuclear antigen (LANA) of HHV-8 were detected by enzyme linked immunosorbent assay and by immunofluorescence assay. HHV-8 DNA from serum or plasma samples was detected by polymerase chain reaction analysis. RESULTS: Antibodies to HHV-8 LANA were detected in 2.9% of the Israeli subjects aged 18-30 years and in 26% of the Ethiopian subjects from both age groups tested. Antibodies to the lytic antigens were detected in all 3 MCD patients, in 4% of the Ethiopian children, and in 2% of the 18- to 30-year-old Ethiopians. No antibodies to the lytic antigens were detected in the Israeli students. HHV-8 DNA was detected in all 3 MCD patients and in 2 of 4 of the Ethiopian children positive for the lytic antigens. CONCLUSIONS: HHV-8 is highly prevalent in Ethiopian immigrants to Israel as compared with Israeli students. Antibodies to HHV-8 in Ethiopia are acquired before puberty. The results of this study indicate the association of HHV-8 with MCD, as has been documented by many other researchers. 相似文献
8.
Tea Kalebic Jeannette E. Williams James E. Talmadge Chien-Song Kao-Shan Betsy Kravitz Kimberly Locklear Gene P. Siegal Lance A. Liotta Mark E. Sobel Patricia S. Steeg 《Clinical & experimental metastasis》1988,6(4):301-318
Tumor cell invasion of basement membranes is required at several steps in the process of metastasis. To study the genetic and biochemical events mediating invasion, a variant cell line (TK) was selected from the metastatic M2 K1735 murine melanoma cell line. A novel selection procedure was used, based onin vitro andin vivo invasion and growth upon basement membrane and stroma. Additionally, two extrapulmonary metastases of the TK cell line, TK-Eve and TK-Liver, were established as cell lines and characterized. The TK cell line demonstrates greater metastatic potentialin vivo and invasive abilityin vitro than the parent M2 cell line, confirming the validity of the selection procedure. In addition, the M2 and TK cell lines were examined for other cell functions involved in the metastatic process. Cellular growth rates and sensitivity to T lymphocyte and natural killer cell lysis were not determining factors in the metastatic potentials of the M2 and selected cell lines; possible macrophage contribution to metastatic behavior was noted. [35S]methionine pulse labeling of protein synthesis and karyotypic analysis confirm the close relationship of parental and selected cell lines.Supported by contract NDI-23910.Supported by ACS Institution Grant IN-15-Y and NIH Grant MRC-5T34-GM08037.Was a fellow of the Jane Coffin Childs Memorial Fund for Medical Research. This investigation has been aided by a grant from the Jane Coffin Childs Memorial Fund for Medical Research. Also supported by NIH Postdoctoral Fellowship #HD06423. 相似文献
9.
Goldberg I Gilburd B Kravitz MS Kivity S Chaim BB Klein T Schiffenbauer Y Trubniykovr E Brenner S Shoenfeld Y 《Clinical & developmental immunology》2005,12(1):85-90
Background: There are several mechanisms to describe allergic drug
reactions yet the methods to diagnose them are limited.
Objective: To compare several conventional clinical and laboratory
methods to diagnose skin reactions to drugs
to a new method of diagnosing drug reactions by the CellScan system.
Methods: The study entailed 21 patients who were diagnosed as
suffering from drug eruptions, and 105 healthy controls with no history of drug
allergy. The drugs were classified into two groups according to suspicion of
causing drug allergy: high and low. Most of the patients were on more than
one drug, leading to 41 patient-drug interactions (assays). Histamine
releasing test (HRT), interferon (INF)-γ releasing test and CellScan
examination were performed on lymphocytes of the patients and controls.
Results: The HRT was interpreted as positive in 9 out of 18 (50%)
patients and in 13 out of 35 (37%) assays. Based on the INF-γ releasing test,
positive results were observed in 16 out of 21 (76%) patients and in 24 out of 41
(59%) assays. In the CellScan test (CST), positive results were observed in 17
out of 21 (81%) patients and in 29 out of 41 (71%) assays. The rate of identifying
the drug for eruption in the high suspicion level drugs was 9 out of 22 (41%)
assays in the HRT, 20 out of 24 (83%) assays in the INF-γ releasing test, and 21
out of 24 (87%) studies with the CellScan method. The rate of determining of
the drug that caused the eruption in the low suspicion level drugs was 4 out of
13 (31%) in the HRT, 4 out of 17 (24%) assays in the INF-γ releasing test, and 8
out of 17 (47%) analyses in the CST. When examined
in the CellScan, 99 out of 105 (94%) controls were interpreted as negative.
Conclusion: This preliminary study indicates that the CellScan seems to
be an easy and promising method for the detection of drugs responsible for
adverse skin reactions. In contrast to the HRT and to the Interferon-γ secretion
test, the CellScan method is characterized by its ability to track and monitor
the reaction of individual cells. By measuring the kinetic parameters of selected
cells before and after adding the suspected drug, we were able to identify
the culprit drug. The CellScan method had the highest sensitivity, and the
interferon-γ secretion test had the highest specificity for detection of the culprit
drug. In contrast, the analysis of 105
normal control sera disclosed a high specificity of 94% for the CellScan method. 相似文献
10.
Shunt nephritis syndrome consists of glomerulonephritis, mixed cryoglobulinemia, and persistent bacteremia. A 37-year-old woman with a prior history of a ventriculoatrial shunt presented complaining of urticaria. A skin biopsy specimen from one lesion showed findings consistent with vasculitis. Because microscopic hematuria was seen on urinalysis, systemic disease was suspected. The ensuing diagnostic workup revealed the syndrome of "shunt nephritis." To our knowledge, cutaneous findings of urticaria and vasculitis have not been previously reported in this interesting syndrome. 相似文献