Class A dioscorins of various yam species suppress ovalbumin-induced allergic reactions.

CONTEXT: Dioscorins, the primary storage proteins in yam tubers, of different species exhibited varying immunomodulatory activities in mice. We inferred that this might be attributed to the various isoforms in the yam tubers. OBJECTIVE: We aimed to investigate the antiallergic potential of the Class A dioscorins of various yam species using the ovalbumin (OVA)-induced murine allergy model. MATERIALS AND METHODS: We purified the recombinant Class A dioscorins (rDioscorins) of various yam species from Escherichia coli and evaluated their antiallergic potential by enzyme-linked immunosorbent assay. RESULTS: The Class A rDioscorins of various yam species suppressed allergic reactions by significantly decreasing the serum IgE and histamine levels. The serum IFN-γ and IgG2a levels significantly increased in all rDioscorin-treated mice. The splenocytes of the rDioscorin-treated mice also exhibited upregulated IFN-γ secretion in response to ConA stimulation. By contrast, the serum IL-5 levels decreased to basal levels in mice treated with Class A rDioscorins and the amount of IL-5 produced by splenocytes decreased in response to ConA stimulation. DISCUSSION: The Class A rDioscorins suppress allergic reactions, possibly through modulating an imbalanced Th1/Th2 immune response to OVA by promoting Th1 cell responses. Furthermore, the Class A rDioscorins of various yam species exhibited similar immunomodulatory activities in OVA-sensitized mice, which were different from the activities demonstrated by native dioscorins, suggesting that distinct immunomodulatory effects of native dioscorins on mice were attributed to the various isoforms in the yam tubers. CONCLUSION: The Class A dioscorins of various yam species exhibit antiallergic activity and are potential immunotherapeutic agents for treating IgE-mediated hypersensitivity.

Comparison of acute lobar nephronia and uncomplicated urinary tract infection in children.

BACKGROUND/PURPOSE: This aim of this study was to assess the clinical manifestations, the microorganisms involved and their antibiotic resistance in children hospitalized due to acute lobar nephronia (ALN) and non-ALN community-acquired urinary tract infections (UTIs). METHODS: We retrospectively reviewed the records of 265 previously healthy children hospitalized due to a first-episode of community-acquired febrile UTI between July 2004 and June 2007. Based on the results of renal ultrasonography and computed tomography, they were divided into ALN and non-ALN groups. Their demographic and clinical characteristics, distribution of microorganisms, and their antimicrobial resistance were analyzed. RESULTS: Of the total number of cases of children admitted with a first-episode community-acquired UTI, 19.2% (n=51) were diagnosed as ALN. Children with ALN were older (1.86 years vs. 0.81 years; p < 0.01), had longer periods of fever before admission (4.7 days vs. 1.4 days; p < 0.01), higher peak body temperatures (39.5°C vs. 38.9°C; p < 0.01), higher white cell counts (18.86 × 10(9)/L vs. 15.08 × 10(9)/L; p < 0.01) and higher C-reactive protein levels (9.0 mg/dL vs. 3.5 mg/dL; p < 0.01) compared with non-ALN children. Fever also persisted for longer after the start of antibiotic treatment in the ALN children (2.7 days vs. 1.4 days: p < 0.01) and they required longer hospital stays and incurred higher medical costs. The major pathogen found in ALN was E. coli (90%). The E. coli isolated from ALN children was more resistant to cotrimoxazole and ciprofloxacin than those from non-ALN children. CONCLUSION: ALN is not uncommon in children with a first-episode febrile UTI. They have a prolonged clinical course, higher inflammatory parameters, longer hospital stays and incur higher medical costs. E. coli is the major pathogen isolated from these children.