Publications by authors named "Rotman H"

At 28 days post-infection autoinfective third-stage larvae (L3a) of Strongyloides stercoralis occurred in jirds infected with 10,000 infective third-stage (L3i). Previously in the jird model of strongyloidiasis, autoinfection had been seen in immunologically immature or immunosuppressed jirds only. The heavily infected jirds described herein had a strong anti-L3i immune response at the same time the living L3a were found in their tissues.

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A leading candidate for a vaccine targeted at the erythrocytic stages of plasmodial parasite development is the merozoite surface protein-1 (MSP-1). We have previously shown that the carboxyl-terminal region of MSP-1 derived from Plasmodium yoelii yoelii 17XL, expressed as a fusion protein with glutathione S-transferase (GST-PYC2), can immunize mice against an otherwise lethal homologous challenge infection. This protection has been shown to be predominantly mediated by antibodies.

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The mechanisms by which Abs mediate protection during blood-stage malaria infections is controversial, with some evidence pointing to the direct effect of Abs on parasite invasion and growth, while other studies suggest that Abs act in cooperation with monocytes to achieve parasite inhibition. To determine whether the effector phase of protection in vivo to the rodent parasite Plasmodium yoelii yoelii requires Fc receptor bearing cells, we passively transferred immune sera into FcR gamma-chain knockout mice. Inflammatory macrophages from these knockout mice were unable to mediate phagocytosis or Ab-dependent cell-mediated cytotoxicity (ADCC) through Fc gamma RI, Fc gamma RII, or Fc gamma RIII.

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Host-adapted, transformed, Strongyloides stercoralis third-stage larvae (L3+) were previously found to be antigenically different from free-living, infective, third-stage larvae (L3). These antigenic differences were reproduced by transformation of free-living larvae in tissue culture medium at 37 C over 24 hr. Transformed L3 of both derivations were given as challenge infections in diffusion chambers to naive mice and mice immunized with S.

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Strongyloidiasis is an intestinal disease that can last for decades due to the occurrence of autoinfective larvae (L3a) in an infected person, which contribute to the maintenance of the population of adult worms in the intestine. The goal of the present study was to determine if L3a are susceptible to the protective immunity that targets the infective stage of the worm, the third-stage larvae (L3). Mice immunized and challenged with Strongyloides stercoralis L3 kill more than 90% of challenge larvae contained within diffusion chambers.

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Background: Inhibition of constitutively expressed cyclooxygenase (Cox-1) is thought to play an important role in the gastrointestinal toxicity of nonsteroidal anti-inflammatory drugs (NSAID), while their therapeutic action may be due to inhibition of the enzyme Cox-2, which is specifically expressed at sites of inflammation. NSAIDs with high affinity and specifity for Cox-2 hold the promise of maintaining efficacy without the gastrointestinal side effects of conventional NSAIDs.

Methods: We assessed the gastrointestinal tolerability of flosulide (20 mg twice a day), a highly selective Cox-2 inhibitor with that of naproxen (500 mg twice a day), which has equal affinity for Cox-1 and -2 in 19 patients with osteoarthrosis in a randomized, double blind, crossover endoscopy study.

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The goal of the present study was to determine if immune-mediated killing of S. stercoralis L3 in mice could be modulated by shifting from a Th-2 to a Th-1 type immune response. L3 killing in immunized mice was ablated in CD4+ T cell-depleted animals, but not in CD8+ T cell-depleted or beta 2-microglobulin-deficient mice.

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We have previously shown that C6 cells expressing an antisense insulin-like growth factor I receptor (IGF-IR) RNA are no longer tumorigenic in syngeneic rats, protecting them from subsequent subcutaneous tumor challenge and causing regression of established subcutaneous tumors. In the present study, we have investigated the efficacy of this strategy on intracerebrally implanted C6 rat glioblastoma cells. We demonstrate that C6 cells expressing an antisense IGF-IR RNA implanted for 24 h in the subcutaneous tissue of the rats are able to elicit an anti-tumor response in the brain, leading to complete brain tumor regression and long-term survival of the rats.

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Mice immunized against Strongyloides stercoralis L3 were shown to kill greater than 90% of challenge larvae contained within diffusion chambers. The objective of the present study was to identify the host components responsible for immunity. Serum from unprotected, control mice and protected, immune mice in doses of 25-500 microliters was transferred into naive mice at the same time and location as larval challenge.

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Challenge worm survival was significantly reduced when BALB/cByJ mice were vaccinated against Strongyloides stercoralis infective third stage larvae (L3) regardless of whether the challenge infections consisted of systemically migrating L3 or L3 implanted in diffusion chambers. The only cell type that increased in number in diffusion chambers in immunized mice, 1 week after booster immunizations, was the eosinophil, and maximal levels of eosinophils were coincident with parasite killing. Mice were treated with mAb to eliminate IL-5 or granulocytes to assess the role that eosinophils play in larval killing.

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Immunization of mice with irradiated Onchocerca volvulus infective stage larvae (L3) has been demonstrated to confer protection against challenge infections with these larvae. Additionally, cytokine level measurements and cytokine depletion studies have shown that both IL-4 and IL-5 are important in generating a protective immune response against O. volvulus challenge infections, thus suggesting a dependency of protective immunity on IgG1, IgE and/or eosinophils.

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Jirds support the entire life-cycle of Strongyloides stercoralis. We therefore used this host as a model to define the mechanism of the immune response to a challenge infection, as well as the parasite stage effected by the response. Jirds given a primary infection of S.

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We have investigated whether there is a quantitative relationship between the insulin-like growth factor I receptor (IGF-IR), the extent of apoptosis in vivo, and tumorigenesis. C6 rat glioblastoma cells were treated with increasing concentrations of antisense oligodeoxynucleotides to the IGF-IR RNA. The extent of apoptosis in vivo is correlated to the decrease in IGF-IR levels and, in turn, tumorigenesis in nude mice is correlated to the fraction of surviving cells.

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The role of the insulin-like growth factor I receptor (IGF-IR) in programmed cell death has been investigated in vivo in a biodiffusion chamber, where the extent of cell death could be determined quantitatively. We found that a decrease in the number of IGF-IRs causes massive apoptosis in vivo in several transplantable tumors, either from humans or rodents. Conversely, an overexpressed IGF-IR protects cells from apoptosis in vivo.

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A murine model system was developed to study the induction and mechanism of protective immunity to L3 of Strongyloides stercoralis. L3 were implanted in BALB/cByJ mice in diffusion chambers constructed with 0.1- or 2.

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In a randomized, double-blind, parallel-group, multicenter study, the efficacy and tolerability of diclofenac dispersible were compared with placebo in the treatment of acute soft-tissue injuries. Patients seen within 48 hours of a soft-tissue injury received either diclofenac dispersible 50 mg or placebo three times daily for 3 to 7 days, with paracetamol allowed as a rescue analgesic. Of a total of 253 recruited patients.

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The analgesic efficacy and patient acceptability of soluble aspirin and diclofenac dispersible were compared in patients with postoperative pain after removal of impacted third molars. A total of 136 patients were randomly allocated to receive soluble aspirin 600 mg tds or diclofenac dispersible 50 mg tds after extraction under local anaesthesia of impacted third molars on one side of the mouth. The medication, which was both patient and operator blind, was reversed after extraction of the contralateral third molars 3 weeks later, the patients acting as their own controls in assessing postoperative pain, pain relief, and interincisal opening.

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Titres of antibodies against hepatitis A virus (HAV) were determined in patients, in donors, and in volunteers after active, passive, and combined immunization. Highest titres were found in recently infected persons: in 109 IgM anti-HAV positive persons, the geometric mean titre (GMT) was 15,400 mIU/ml. The GMT in 265 anti-HAV positive blood donors was 10,700 mIU/ml.

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A patient is described who underwent percutaneous transluminal angioplasty, through a brachial approach, of a high grade stenosis at the proximal portion of the left subclavian artery 1.5 years after coronary artery bypass grafting including left internal mammary to left anterior descending artery anastomosis. Symptoms of class IV angina, vertebrobasilar insufficiency and occupational arm claudication that developed after bypass surgery were promptly relieved after balloon dilation.

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The efficacy and tolerability of a new dispersible formulation of diclofenac were evaluated in a randomized, double-blind, placebo-controlled, multi-centre study in patients aged 60 to 80 years suffering from osteoarthritis. A total of 314 elderly patients with a mean age of 68.9 years received either 50 mg diclofenac dispersible or placebo 3-times daily for a period of 4 weeks, with paracetamol being allowed as rescue analgesic for both treatment groups.

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Effects of the nonsteroidal anti-inflammatory drug, diclofenac, on stimulated monocyte superoxide production were assessed directly in vitro and following treatment of patients with rheumatoid arthritis ex vivo. Diclofenac inhibited superoxide generation provoked by serum treated zymosan (STZ) and fluoride anion (F) but not by phorbol myristate acetate (PMA) in vitro. Following patient therapy, inhibition of superoxide production occurred when STZ and PMA, but not F were used as stimuli.

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A paraplegic patient who underwent the placement of Greenfield filters to prevent pulmonary emboli had one of the filters migrate proximally to the junction of the inferior vena cava and right atrium, then into the right atrium a few months later. This resulted in an acute myocardial infarction by apparently causing an intimal dissection of the posterior descending artery. Treatment, follow-up and causes of filter migration are discussed.

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