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Dive into the research topics where Vivian Barak is active.

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Featured researches published by Vivian Barak.


Tumor Biology | 2005

Tumor Markers in Breast Cancer – European Group on Tumor Markers Recommendations

Rafael Molina; Vivian Barak; Arie van Dalen; Michael J. Duffy; R. Einarsson; Massimo Gion; Helena Goike; Rolf Lamerz; Marius Nap; György Sölétormos; Petra Stieber

Recommendations are presented for the routine clinical use of serum and tissue-based markers in the diagnosis and management of patients with breast cancer. Their low sensitivity and specificity preclude the use of serum markers such as the MUC-1 mucin glycoproteins (CA 15.3, BR 27.29) and carcinoembryonic antigen in the diagnosis of early breast cancer. However, serial measurement of these markers can result in the early detection of recurrent disease as well as indicate the efficacy of therapy. Of the tissue-based markers, measurement of estrogen and progesterone receptors is mandatory in the selection of patients for treatment with hormone therapy, while HER-2 is essential in selecting patients with advanced breast cancer for treatment with Herceptin (trastuzumab). Urokinase plasminogen activator and plasminogen activator inhibitor 1 are recently validated prognostic markers for lymph node-negative breast cancer patients and thus may be of value in selecting node-negative patients that do not require adjuvant chemotherapy.


Annals of the New York Academy of Sciences | 2007

Novel biomarkers in autoimmune diseases : Prolactin, ferritin, vitamin D, and TPA levels in autoimmune diseases

Hedi Orbach; Gisele Zandman-Goddard; Howard Amital; Vivian Barak; Zoltán Szekanecz; Gabriella Szücs; Katalin Dankó; Endre V. Nagy; Tünde Csépány; Jozélio Freire de Carvalho; Andrea Doria; Yehuda Shoenfeld

Abstract:  The development of autoimmune diseases may be influenced by hormonal, immunomodulatory, and metabolic pathways. Prolactin (PRL), ferritin, vitamin D, and the tumor marker tissue polypeptide antigen (TPA) were measured in autoimmune diseases: systemic lupus erythematosus (SLE), systemic sclerosis (SSc), rheumatoid arthritis (RA), polymyositis (PM), dermatomyositis (DM), multiple sclerosis (MS), autoimmune thyroid diseases, and antiphospholipid syndrome. Hyperprolactinemia (HPRL) was detected in 24% of PM patients, in 21% of SLE patients, in 6.7% of MS patients, 6% of RA patients, and in 3% of SSc patients. Hyperferritinemia was detected in 23% of SLE patients, 15% of DM patients, 8% of MS patients, and 4% of RA patients. The patients had relatively low levels of 25 OH Vitamin D: the average results (mean ± SD) were between 9.3 ± 4.4 to 13.7 ± 7.1 ng/mL in the different diseases, while the 25 OH Vitamin D concentrations less than 20 ng/mL are regarded as deficient. TPA levels were in the same range of the controls, elevated only in SLE. HPRL, hyperferritinemia, hypovitaminosis D, and TPA levels did not correlate with SLE activity elevated levels of rheumatoid factor or anti‐CCP antibodies in RA. HPRL, hyperferritinemia, and hypovitaminosis D have different immunological implications in the pathogenesis of the autoimmune diseases. Preventive treatment with vitamin D or therapy for HPRL with dopamine agonists, may be considered in certain cases. Hyperferritinemia may be used as an acute‐phase reactant marker in autoimmune diseases mainly SLE. TPA may be used to indicate the tendency for malignancies.


The American Journal of Medicine | 1998

Prevalence of Hypophosphatemia in Sepsis and Infection: The Role of Cytokines ☆

Vivian Barak; Audrey Schwartz; Inna Kalickman; Benjamin Nisman; Gaby Gurman; Yehuda Shoenfeld

BACKGROUND Sepsis occurs following the presence of bacteria in the circulation and is associated with fever, hyperthermia, and hypotension. Hypophosphatemia develops in the early stages of sepsis. High levels of inflammatory cytokines also characterize early sepsis. AIM The aim of the present study was to correlate hypophosphatemia with cytokines and cytokine receptor levels during early sepsis. We aimed to reestablish the results obtained from patients in an in vivo experimental model, in order to understand the mechanism of hypophosphatemia induction in early sepsis. METHODS Ninety-nine patients were enrolled in this study and their clinical condition was classified as the presence of infection, sepsis, and bacterial growth in blood cultures. Phosphate levels and cytokine levels were recorded. In order to determine whether hypophosphatemia is correlated to the increased inflammatory cytokines, we injected normal mice with recombinant cytokines and studied their effect on phosphate levels. RESULTS Our results revealed that 80% of the septic patients had hypophosphatemia associated with very high levels of tumor necrosis factor (TNF)alpha and interleukin (IL)-6 and of soluble IL receptor (sIL)-2R and IL-6R, especially in those patients with positive blood cultures. Injection of IL-6, TNFalpha and IL-1beta in mice markedly decreased the phosphate serum levels. CONCLUSIONS Significant associations were demonstrated between high levels of inflammatory cytokines and their receptors and between serum phosphate levels, especially in patients with positive blood culture. Our results point to a correlation between the high inflammatory cytokines levels and hypophosphatemia during early sepsis. Cytokine levels and hypophosphatemia may be included in sepsis evaluation and prognosis. Anticytokine strategies might, therefore, reverse hypophosphatemia and other parameters of sepsis.


Cancer | 1998

Evaluation of tissue polypeptide specific antigen, CYFRA 21-1, and carcinoembryonic antigen in nonsmall cell lung carcinoma

Benjamin Nisman; Joel Lafair; Norman Heching; Olga Lyass; Mario Baras; Tamar Peretz; Vivian Barak

Recently developed tissue polypeptide specific antigen (TPS) and CYFRA 21‐1 assays determine the soluble cytokeratin 18 and 19 fragments, respectively, in serum. The authors compared the value of TPS, CYFRA 21‐1, and carcinoembryonic antigen (CEA) for the diagnosis, staging, prognosis, and monitoring of patients with nonsmall cell lung carcinoma (NSCLC).


Cancer | 2002

Evaluation of urine CYFRA 21-1 for the detection of primary and recurrent bladder carcinoma

Benjamin Nisman; Vivian Barak; Amos Shapiro; Dragan Golijanin; Tamar Peretz; Dov Pode

The urinary concentration of soluble cytokeratin 19 fragments, measured by the CYFRA 21‐1 assay, may be used for the noninvasive, early detection of bladder carcinoma.


Clinical Chemistry | 2015

Validation of New Cancer Biomarkers: A Position Statement from the European Group on Tumor Markers

Michael J. Duffy; Catharine M. Sturgeon; György Sölétormos; Vivian Barak; Rafael Molina; Daniel F. Hayes; Eleftherios P. Diamandis; Patrick M. Bossuyt

BACKGROUND Biomarkers are playing increasingly important roles in the detection and management of patients with cancer. Despite an enormous number of publications on cancer biomarkers, few of these biomarkers are in widespread clinical use. CONTENT In this review, we discuss the key steps in advancing a newly discovered cancer candidate biomarker from pilot studies to clinical application. Four main steps are necessary for a biomarker to reach the clinic: analytical validation of the biomarker assay, clinical validation of the biomarker test, demonstration of clinical value from performance of the biomarker test, and regulatory approval. In addition to these 4 steps, all biomarker studies should be reported in a detailed and transparent manner, using previously published checklists and guidelines. Finally, all biomarker studies relating to demonstration of clinical value should be registered before initiation of the study. SUMMARY Application of the methodology outlined above should result in a more efficient and effective approach to the development of cancer biomarkers as well as the reporting of cancer biomarker studies. With rigorous application, all stakeholders, and especially patients, would be expected to benefit.


Radiation Oncology | 2010

Cytokines levels, Severity of acute mucositis and the need of PEG tube installation during chemo-radiation for head and neck cancer - a prospective pilot study

Amichay Meirovitz; Michal Kuten; Salem Billan; Roxolyana Abdah-Bortnyak; Anat Sharon; Tamar Peretz; Mordechai Sela; Moshe Schaffer; Vivian Barak

BackgroundThe purpose of this pilot study was to detect a correlation between serum cytokine levels and severity of mucositis, necessitating installation of a percutaneous endoscopic gastrostomy tube (PEG) in head and neck (H&N) cancer patients receiving combined chemo-radiation therapy.Patients and MethodsFifteen patients with H&N epithelial cancer were recruited to this study. All patients received radiotherapy to the H&N region, with doses ranging from 50-70 Gy. Chemotherapy with cisplatin, carboplatin, 5-fluorouracil and taxanes was given to high-risk patients, using standard chemotherapy protocols. Patients were evaluated for mucositis according to WHO common toxicity criteria, and blood samples were drawn for inflammatory (IL-1, IL-6, IL-8, TNF-α) and anti-inflammatory (IL-10) cytokine levels before and during treatment.ResultsA positive correlation was found between IL-6 serum levels and severity of mucositis and dysphagia; specifically, high IL-6 levels at week 2 were correlated with a need for PEG tube installation. A seemingly contradictory correlation was found between low IL-8 serum levels and a need for a PEG tube.ConclusionThese preliminary results, indicating a correlation between IL-6 and IL-8 serum levels and severity of mucositis and a need for a PEG tube installation, justify a large scale study.


Annals of Neurology | 2012

Losartan, a therapeutic candidate in congenital muscular dystrophy: Studies in the dy2J/dy2J Mouse

M. Elbaz; Nurit Yanay; Shlomit Aga-Mizrachi; Z. Brunschwig; Ibaa Kassis; Keren Ettinger; Vivian Barak; Yoram Nevo

Lamininα2‐deficient congenital muscular dystrophy type 1A (MDC1A) is a cureless disease associated with severe disability and shortened lifespan. Previous studies have shown reduced fibrosis and restored skeletal muscle remodeling following treatment with losartan, an angiotensin II type I receptor blocker. We therefore evaluated the effect of losartan treatment in the dy2J/dy2J mouse model of MDC1A.


Journal of Autoimmunity | 2009

Serum inflammatory cytokines, complement components, and soluble interleukin 2 receptor in primary biliary cirrhosis

Vivian Barak; Carlo Selmi; M. Schlesinger; Miri Blank; Nancy Agmon-Levin; I. Kalickman; M. E. Gershwin; Yehuda Shoenfeld

Primary biliary cirrhosis (PBC) is a chronic cholestatic autoimmune liver disease characterized by selective destruction of the intrahepatic bile ducts and highly specific serum anti-mitochondrial autoantibodies (AMA). Several studies have attempted to determine the cytokine pattern characterizing PBC, yet no definitive data have been gathered. The present study was designed to evaluate pro-inflammatory cytokines (IL-1beta, IL-6, TNFalpha), soluble IL-2 receptor (sIL-2R, e.g. soluble CD25), and complement components (C1q, C3, factor B, properdin) levels in sera from 84 patients with PBC and 41 controls. PBC was characterized by significantly higher levels of all pro-inflammatory cytokines when compared to controls; these included IL-1beta (433.3 +/- 13.2 vs. 316.6 +/- 14.7 pg/ml, P < 0.001), IL-6 (701 +/- 17.4 vs. 158 +/- 22.5 pg/ml, P < 0.001), TNFalpha (3.38 +/- 0.6 pg/ml vs. undetectable, P = 0.001), and sIL-2R (1527.1 +/- 106 vs. 566.4 +/- 28.7 U/ml, P < 0.001). Similarly, all complement components were also significantly higher in PBC compared to control sera. In conclusion, PBC sera manifest higher levels of sIL-2R and complement components and this may reflect a perpetuated immune activation. As expected, we also report that all major pro-inflammatory cytokine levels are enhanced in PBC. Further longitudinal analyses could demonstrate a correlation between these markers and disease stage or inflammatory activity, to predict histological staging, disease activity, and response to treatment.


Fertility and Sterility | 1992

Interleukin-1: local production and modulation of human granulosa luteal cells steroidogenesis

Vivian Barak; Peter Yanai; Abraham J. Treves; Isaac Roisman; Alexander Simon; Neri Laufer

OBJECTIVES To investigate the possibility of local interleukin-1 (IL-1) and IL-1 inhibitor production by human granulosa and cumulus cells and to assess their direct effects on the steroidogenesis of these cells in vitro. DESIGN Prospective study. PARTICIPANTS Normal ovulatory women undergoing ovulation induction for in vitro fertilization. INTERVENTION Pretreatment of patients with gonadotropin-releasing hormone analogue, human menopausal gonadotropin, and human chorionic gonadotropin (hCG). MAIN OUTCOME MEASURES Retrieval and isolation of granulosa luteal cells and follicular fluid (FF). Granulosa luteal cells and cumulus cells cultured and analyzed by fluorescent activated cell sorter. Follicular fluid separated and bioassayed for IL-1 and IL-1 inhibitory activity. Steroid measurement performed. Interleukin-1 inhibitor purified. Interleukin-1 and IL-1 inhibitor bioassay performed. Statistical analysis made and interpreted. RESULTS Interleukin-1, but not IL-1 specific inhibitory activity, was found in granulosa and cumulus cell cultures and also in FF, only after its purification on a high-pressure liquid chromatography column. Under nonstimulated conditions, neither IL-1 nor IL-1 inhibitor had any effect on basal progesterone (P) or estradiol (E2) secretion. However, IL-1 inhibitor demonstrated significant (P < 0.01) inhibition of hCG-stimulated P secretion (from 200 to 110 ng/10,000 cells per 24 hours). In addition, IL-1 demonstrated a significant (P < 0.05) and dose-dependent inhibition of hCG-stimulated E2 production (from 6,832 +/- 460 to 4,237 +/- 141 pg/10,000 cells per 24 hours). CONCLUSIONS Interleukin-1 may exert a significant local autocrine regulatory role in the human ovary.

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Inna Kalickman

Hebrew University of Jerusalem

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Jacob Pe'er

Hebrew University of Jerusalem

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Benjamin Nisman

Hebrew University of Jerusalem

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Shahar Frenkel

Hebrew University of Jerusalem

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Tamar Peretz

Hebrew University of Jerusalem

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Yoram Abramov

Hebrew University of Jerusalem

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Peter Yanai

Hebrew University of Jerusalem

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