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Dive into the research topics where Ram Reifen is active.

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Featured researches published by Ram Reifen.


Allergy | 2002

Food allergy is a matter of geography after all: sesame as a major cause of severe IgE-mediated food allergic reactions among infants and young children in Israel.

Ilan Dalal; Inga Binson; Ram Reifen; Z. Amitai; T. Shohat; S. Rahmani; Arie Levine; Ami Ballin; Eli Somekh

Objective: To determine the prevalence, importance, and the order of frequency of IgE‐mediated food allergens among infants and young children in Israel.


Nutrition Reviews | 2008

Update on alpha-linolenic acid

Aliza H. Stark; M.A. Crawford; Ram Reifen

Consumption of omega 3 fatty acids is known to have health benefits. For many years, the importance of the only member of the omega 3 family considered to be essential, alpha-linolenic acid (ALA), has been overlooked. Current research indicates that ALA, along with its longer chain metabolites, may play an important role in many physiological functions. Potential benefits of ALA include cardioprotective effects, modulation of the inflammatory response, and a positive impact on both central nervous system function and behavior. Recommended levels for ALA intake have been set, yet the possible advantages of its consumption are just being revealed.


Journal of Gastroenterology | 2004

5-ASA and lycopene decrease the oxidative stress and inflammation induced by iron in rats with colitis.

Ram Reifen; Andreea Nissenkorn; Z. Matas; Yoram Bujanover

BackgroundSupplementation of 5-aminosalicylic acid (5-ASA) and of iron are among the principal therapies in patients with inflammatory bowel disease. Therapeutic iron, as well as heme iron from chronic mucosal bleeding, can increase iron-mediated oxidative stress in colitis. This study was designed to examine the influence of iron supplementation on histological expression and oxidative status relative to 5-ASA treatment and antioxidant treatment.MethodsColitis was induced using the iodoacetamide rat model, and rats were divided into different dietary groups of 6 rats each: 1, normal chow diet (control); 2, diet supplemented with iron; 3, iron supplementation and lycopene; 4, iron and Β-carotene; 5, 5-ASA; 6, 5-ASA and lycopene; 7, 5-ASA and iron; 8, 5-ASA, iron, and lycopene. The animals were killed after 3 days and the weight of the ulcerated area recorded. Mucosal specimens were histologically evaluated. Myeloperoxidase (MPO) was measured to evaluate inflammatory status (U/g). Malondialdehyde (MDA) was measured in colonic tissue (µmol/g) and superoxide dismutase (SOD) in erythrocytes to assess the degree of tissue oxidative stress.ResultsSignificantly more severe colitis, including necrosis, ulceration, and hemorrhage, was seen in colonic biopsies of rats with colitis when iron was supplemented. This pathology was attenuated when iron was given in combination with 5-ASA and/or lycopene. There was no significant benefit from adding Β-carotene.ConclusionsIron supplementation can amplify the inflammatory response and subsequent mucosal damage in a rat model of colitis. We suggest that the resultant oxidative stress generated by iron supplementation leads to the extension and propagation of crypt abscesses, either through direct membrane disruption by lipid peroxidation or through the generation of secondary toxic oxidants. Simultaneous treatment with 5-ASA and/or lycopene minimizes the potential hazard of iron. Therefore, we suggest giving iron supplementation with 5-ASA or lycopene or both.


Proceedings of the Nutrition Society | 2002

Vitamin A as an anti-inflammatory agent

Ram Reifen

Vitamin A is necessary for normal differentiation of epithelial tissues, the visual process and reproduction, and is vital for the optimal maintenance and functioning of the innate and adaptive immune system. Vitamin A deficiency is one of the most profuse nutritional deficiencies worldwide. It is associated with increased susceptibility to infectious diseases in both man and animal models. Vitamin A also has a role as an anti-inflammatory agent. Supplementation with vitamin A has been found to be beneficial in a number of inflammatory conditions, including skin disorders such as acne vulgaris, broncho-pulmonary dysplasia and some forms of precancerous and cancer states. The present review suggests that vitamin A deficiency induces inflammation and aggravates existing inflammatory states. Supplementation with vitamin A in selected cases could ameliorate inflammation. The two main mechanisms which appear to be involved in the prevention of disease are the effects of vitamin A on the immune system and the effect on epithelial integrity.


Digestive Diseases and Sciences | 2000

Iron supplementation may aggravate inflammatory status of colitis in a rat model.

Ram Reifen; Z. Matas; Lilian Zeidel; Zippi Berkovitch; Yoram Bujanover

Iron supplementation is one of the principal therapies in inflammatory bowel disease. Iron is a major prooxidative agent; therefore therapeutic iron as well as heme iron from chronic mucosal bleeding can increase the iron-mediated oxidative stress in colitis by facilitating the Fenton reaction, namely production of hydroxyl radicals. In the present study colitis was induced in the iodoacetamide rat model. Forty male Whistar rats were divided into four groups, each group receiving a different diet regimen in parallel with colitis induction: Malondialdehyde was measured to assess the degree of tissue oxidative stress. There were microscopic changes, and significantly more severe colitis was seen in colonic biopsies when iron was supplemented. It was concluded that iron supplementation can amplify the inflammatory response and enhance the subsequent mucosal damage in a rat model of colitis. We suggest that the resultant oxidative stress generated by iron supplementation leads to the extension and propagation of crypt abscesses.


Journal of Hepatology | 2002

Pyrrolidine dithiocarbamate protects against thioacetamide-induced fulminant hepatic failure in rats

Rafael Bruck; Hussein Aeed; Ron Schey; Zipora Matas; Ram Reifen; Gidi Zaiger; Ayala Hochman; Yona Avni

BACKGROUND/AIMS Reactive oxygen species and nuclear factor kappa B (NF-kappaB) activation have been implicated in the pathogenesis of cell injury in experimental models of liver damage. The aim of the present study was to examine whether pyrrolidine dithiocarbamate (PDTC), an anti oxidant and inhibitor of NF-kappaB activation, would prevent hepatic damage induced in a rat model of thioacetamide (TAA)-induced liver failure. METHODS Fulminant hepatic failure was induced in the control and treatment groups by two intraperitoneal injections of TAA (either 300 or 400 mg/kg) at 24-h intervals. In the treatment groups, rats were treated also with PDTC (60 mg/kg/24 h, i.p.), initiated 24 h prior to TAA. RESULTS Liver enzymes, blood ammonia, and hepatic levels of thiobarbituric acid reactive substances (P<0.001) and protein carbonyls (P<0.05) were significantly lower in rats treated with PDTC compared to TAA only. Liver histology and the survival rate in the PDTC-treated rats were also improved (P<0.01 compared to TAA only). NF-kappaB activation, 2 and 6 h after TAA administration, was inhibited by PDTC. CONCLUSIONS In a rat model of fulminant hepatic failure, the administration of PDTC attenuated liver damage and improved survival. This effect may be due to decreased oxidative stress and inhibition of NF-kappaB activation.


Pediatrics | 2010

Effect of Music by Mozart on Energy Expenditure in Growing Preterm Infants

Ronit Lubetzky; Francis B. Mimouni; Shaul Dollberg; Ram Reifen; Gina Ashbel; Dror Mandel

OBJECTIVE: The rate of weight gain in preterm infants who are exposed to music seems to improve. A potential mechanism could be increased metabolic efficiency; therefore, we conducted this study to test the hypothesis that music by Mozart reduces resting energy expenditure (REE) in growing healthy preterm infants. DESIGN. A prospective, randomized clinical trial with crossover was conducted in 20 healthy, appropriate-weight-for-gestational-age, gavage-fed preterm infants. Infants were randomly assigned to be exposed to a 30-minute period of Mozart music or no music on 2 consecutive days. Metabolic measurements were performed by indirect calorimetry. RESULTS: REE was similar during the first 10-minute period of both randomization groups. During the next 10-minute period, infants who were exposed to music had a significantly lower REE than when not exposed to music (P = .028). This was also true during the third 10-minute period (P = .03). Thus, on average, the effect size of music on REE is a reduction of ∼10% to 13% from baseline, an effect obtained within 10 to 30 minutes. CONCLUSIONS: Exposure to Mozart music significantly lowers REE in healthy preterm infants. We speculate that this effect of music on REE might explain, in part, the improved weight gain that results from this “Mozart effect.”


Pediatric Allergy and Immunology | 2003

The pattern of sesame sensitivity among infants and children.

Ilan Dalal; Inga Binson; Arie Levine; Eli Somekh; Ami Ballin; Ram Reifen

Recently, we found sesame to be a major cause of severe IgE‐mediated food allergic reactions among infants and young children in Israel. The purpose of this study was to describe the different patterns of sesame sensitivity. We have identified three subgroups among our patients (n = 32). Group I (n = 23, M/F; 14/9) consisted of cases with IgE‐mediated sesame allergy. The mean age of the first allergic reaction was 11.7 months. Although the main clinical manifestation was urticaria/angiedema (n = 14, 60%), anaphylaxis was the presenting symptom in seven (30%) patients; all of them were younger than 1 year. Sixteen (70%) were found to be allergic to other foods, and other atopic diseases were identified in 18 (78%) patients. Three patients ‘outgrew’ their allergy within 1–2 years. Group II (n = 2) included cases in whom sesame allergy was ruled out based on a negative skin prick test (SPT) together with a negative open oral challenge. Group III (n = 7) consisted of patients that were found to be SPT positive for sesame as part of a screening for other food allergies. Although sesame products have become fashionable in westernized countries, early exposure may cause sesame to share eventually the same ‘noteriety and fate’ as peanut – a major cause of severe food allergic reactions.


International Journal of Std & Aids | 1997

Infection with HIV, syphilis and hepatitis B in Ethiopia: a survey in blood donors

S I Rahlenbeck; G Yohannes; K Molla; Ram Reifen; A Assefa

Sera of all male donors appearing at the blood bank of a regional hospital in Northwest Ethiopia in 1994 (n=1022) and 1995 (n=1164), were screened for the presence of human immunodeficiency virus (HIV-1) and treponemal antibodies. Additionally, screening for hepatitis B surface antigen (HBsAg) was carried out on 549 consecutive sera. In 1995, the crude seroprevalence of HIV-1 infection and syphilis was 16.7% and 12.8%. Seroprevalence of HBsAg was 14.4%. HIV and syphilis seroprevalence was highest in soldiers (30.6% and 20.9%) and daily workers (18.8% and 13.5%), and lowest in farmers (8% and 6.7%). However, farmers had the highest rate of HBsAg (18.8%). HIV-positive donors had an increased risk for being positive for syphilis antibodies (OR=3.69, 95% CI=2.69-4.96), but not for HBsAg (OR=0.79, 95% CI=0.361.67). The data indicate that (i) the HIV epidemic has not yet reached a plateau phase in Ethiopia, and (ii) the transmission and epidemiology of HBsAg in Ethiopia is different from that of HIV and syphilis.


British Poultry Science | 2000

Vitamin A deficiency interferes with proliferation and maturation of cells in the chicken small intestine

Z. Uni; Gidi Zaiger; O. Gal-Garber; M. Pines; I. Rozenboim; Ram Reifen

1. The effect of vitamin A on the small intestine was examined in vitamin-A-deficient meat-type chickens. 2. Maturation and activity of the small intestinal cells were assayed by detection of proliferating cells with proliferating cells nuclear antigen, goblet cells with Alcian blue, mature cells with alkaline phosphatase and extent of RNA expression with dot blot analysis. 3. Vitamin A deficiency caused hyperproliferation of enterocytes, a decrease in the number of goblet cells, decreased alkaline phosphatase activity and decreased expression of 2 brush-border enzymes. 4. Our findings suggest that the absence of vitamin A interferes with the normal growth rate in chickens because it influences functionality of the small intestine by altering proliferation and maturation of cells in the small intestinal mucosa.

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Zvi Zadik

Kaplan Medical Center

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Zipi Berkovich

Hebrew University of Jerusalem

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Amnon Zung

Hebrew University of Jerusalem

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Z. Uni

Hebrew University of Jerusalem

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Shimrit Bar-El Dadon

Hebrew University of Jerusalem

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Aliza H. Stark

Hebrew University of Jerusalem

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David Branski

Hebrew University of Jerusalem

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Einat Amit-Romach

Hebrew University of Jerusalem

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Oren Tirosh

Hebrew University of Jerusalem

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Zippi Berkovich

Hebrew University of Jerusalem

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