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N Sharon

Publications and source records attributed to N Sharon.

300 records · Page 17Linked to original sources
PubMed1966

Polysaccharides.

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Animals↗
PubMedDate not supplied

Safe as mother's milk: carbohydrates as future anti-adhesion drugs for bacterial diseases.

The majority of infectious diseases are initiated by adhesion of pathogenic organisms to the tissues of the host. In many cases, this adhesion is mediated by lectins present on the surface of the infectious organism that bind to complementary carbohydrates on the surface of the host tissues. Lectin-deficient mutants often lack ability to initiate infection. Soluble carbohydrates recognized by the bacterial lectins block the adhesion of the bacteria to animal cells in vitro. Moreover, they have also been shown to protect against experimental infection by lectin-carrying bacteria in different organs of mammals such as mice, rabbits, calves and monkeys. In a phase II clinical trial, a pentasaccharide shown to have anti-adhesive activity against Streptococcus pneumoniae and Hemophilus influenzae in vitro failed to protect young children from nasopharyngeal colonization with these organisms and from developing otitis media. This could be because insufficient drug was delivered via nasal spray, because bacteria express multiple specificities, the inhibition of which may require a cocktail of oligosaccharides, or because children have different carbohydrate receptors from those of adults. The results of a clinical trial in which N-acetylneuraminyl(alpha2-3)lactose was administered orally to Helicobacter pylori positive patients in an effort to reduce or eradicate bacterial colonization, are awaited with interest. Although the high cost of production of the required oligosaccharides is falling with the recent introduction of enzymatic methods of synthesis, new technologies, in particular the use of engineered bacteria, promise to lower it even further. Attachment of the oligosaccharides to soluble polymeric carriers will increase greatly their effectiveness as antiadhesion agents. There is no doubt that anti-adhesive oligosaccharides will in the near future join the arsenal of drugs for the therapy of bacterial diseases.

Adult↗
PubMedDate not supplied

Suppression of bacterial adherence by subminimal inhibitory concentrations of beta-lactam and aminoglycoside antibiotics.

Nonseptate filaments of Escherichia coli obtained by growth of a temperature-sensitive mutant of the organism at its restrictive temperature in the absence of antibiotics or at its permissive temperature in the presence of approximately one-half the MIC of penicillin (27 micrograms/ml; MIC of penicillin, 50 micrograms/ml) lacked the ability both to bind to mannose and to adhere to host tissues. Addition of low concentrations (0.5-10 micrograms/ml) of streptomycin to cultures of E. coli resulted in marked suppression of the mannose-binding and adhering ability of streptomycin-sensitive E. coli (MIC, 30 micrograms/ml). In contrast, up to 5,000 microgram of streptomycin/ml had no effect on an isogenic streptomycin-resistant mutant of E. coli (MIC, 20,000 micrograms/ml). No concentration of penicillin or streptomycin that was tested was able to suppress either the mannose-binding or the adhering ability of E. coli once those activities had been acquired by the organism. These results suggest that subminimal inhibitory concentrations of antibiotics suppress the ability of bacteria to adhere to cells.

Adhesiveness↗
PubMedDate not supplied

Chromosomal translocation (1:13) in a case of alveolar rhabdomyosarcoma.

PURPOSE: To describe a patient with a variant translocation (1;13)(p36;q14) in an alveolar rhabdomyosarcoma and compare the clinical course with four other cases. PATIENTS AND METHODS: A 10-year-old girl presented with multiple masses involving the thigh, abdomen, chest wall, and scalp with pleural effusion and edema of the lower extremities. RESULTS: A bone marrow biopsy, aspirate, and biopsy of the thigh mass all showed tumor invasion. Histopathology and cytogenetics of the thigh mass revealed an alveolar rhabdomyosarcoma with a t(1;13)(p36q14) variant. There was no response to aggressive therapy and the patient died within 3 weeks of admission. CONCLUSION: Variant t(1;13)(p36;q14) has now been described in 5 cases of rhabdomyosarcoma, and may define a subset of patients with extensive disease at diagnosis unresponsive to current therapeutic modalities.

Child↗
PubMedDate not supplied

Helicobacter pylori-associated gastric lymphoma in a girl.

We present a case of a 14-year-old girl with gastric large cell lymphoma. The girl's lymphoma was characterized by the presence of mucosa-associated lymphoid tissue. Infection with Helicobacter pylori (HP) was ascertained at the time of diagnosis. The girl was successfully treated by a combination of chemotherapy (MACOP-B) and anti-HP drugs (omeprazole plus amoxicillin). Thrombus of the inferior vena cava, a rare complication, evolved during treatment.

Adolescent↗