Toxicity of legume seeds to rhizobia: Selective marker for strain identification and selection of toxin-free seeds

Seeds of legume species Argyrolobium flaccidum, Desmodium elegans, D. tortuosum, Indigofera gangetica, Lespedeza stenocarpa and Sesbania sesban have been evaluated for the toxicity to rhizobia for the first time. Legume species differ in quantity and quality of released seed toxins to which the symbiotic bacteria respond differentially. Therefore, seed toxicity may be used as a selectable taxonomic marker for the strainal identification of rhizobia. Seed toxins are located in seed coat and are thermolabile to some extent. The seed genotypes, within the species, differ in toxicity and such polymorphism can be used in the selection of toxin-free seeds. Seed surface-disinfection procedures involving subsequent soaking and washing with water are the most useful methods for reducing the seed toxins. The seed toxins from I. gangetica inhibited the growth of its homologous strain but did not affect nodulation and symbiotic parameters. Various seed-toxin-producing legume species did not affect nodulation and symbiotic efficiency and effectiveness.     

The nonspecific symptom screening method. Detection of nonpsychotic morbidity based on nonspecific symptoms

Detection of nonpsychotic morbidity in primary care patients presenting with nonspecific and somatic symptoms has been difficult because of several factors related to the patients, primary care clinicians, and working conditions of the over-crowded clinic. The available standardized screening questionnaires do not overcome many of these difficulties when used for routine clinical purposes. A screening method based only on nonspecific symptoms, which could be easily incorporated into the routine initial clinical work-up of a patient, was developed in this study and has been found to have good validity and reliability for screening nonpsychotic morbidity. The method of construction of the screen and its clinical applicability and limitations are discussed.     

Efficacy and safety of ezetimibe coadministered with pravastatin in patients with primary hypercholesterolemia: a prospective, randomized, double-blind trial.

AIMS: To evaluate the efficacy and safety of ezetimibe 10 mg administered with pravastatin in patients with primary hypercholesterolemia. METHODS AND RESULTS: After dietary stabilization, 2-12 week screening/washout period, and 4-week, single-blind, placebo lead-in period, 538 patients with baseline LDL-C > or =3.8 to < or =6.5 mmol/l and TG < or =4.0 mmol/l were randomized to one of eight possible treatments administered daily for 12 weeks: ezetimibe 10mg; pravastatin 10, 20, or 40 mg; ezetimibe 10 mg plus pravastatin 10, 20, or 40 mg; or placebo. The primary efficacy endpoint was percent reduction in LDL-C from baseline to study endpoint for ezetimibe 10 mg plus pravastatin (pooled doses) compared to pravastatin alone (pooled doses) and ezetimibe alone. The combined use of ezetimibe and pravastatin resulted in significant incremental reductions in LDL-C and TG compared to pooled pravastatin alone (p<0.01). Coadministration therapy reduced LDL-C by 34-41%, TG by 21-23%, and increased HDL-C by 7.8-8.4%, depending on the dose of pravastatin. The combined regimen was well tolerated, with a safety profile similar to pravastatin alone and placebo. CONCLUSIONS: When coadministered with pravastatin, ezetimibe provided significant incremental reductions in LDL-C and TG and was well tolerated with a safety profile similar to pravastatin alone.     

Development of immunofiltration assay by light addressable potentiometric sensor with genetically biotinylated recombinant antibody for rapid identification of Venezuelan equine encephalitis virus

A genetically biotinylated single chain fragment variable antibody (scFv) against Venezuelan equine encephalitis virus (VEE) was applied in a system consisting of an immunofiltration enzyme assay (IFA) with a light addressable potentiometric sensor (LAPS) for the rapid identification of VEE. The IFA involved formation of an immunocomplex sandwich consisting of VEE, biotinylated antibody, fluoresceinated antibody and streptavidin, capture of the sandwich by filtration on biotinylated membrane, and labeling of the sandwich by anti-fluorescein urease conjugate. The concentration ratio of biotinylated to fluoresceinated antibodies was investigated and optimized. By the IFA/LAPS assay, the limit of detection (LOD) of VEE was approximately 30 ng/ml, similar to that achieved when chemically biotinylated monoclonal antibody (mAb) was applied. Total assay variance of the IFA/LAPS assay for both intra- and inter-assay precision was less than 20%. Assay accuracy was measured by comparing VEE concentrations estimated by IFA/LAPS standard curve to those obtained by conventional protein assay. VEE concentrations were found to differ by no more than 10%. The IFA/LAPS assay sensitivity was approximately equal to that of a conventional enzyme-linked immunosorbent assay (ELISA) utilizing polystyrene plates and a chromogenic substrate; however, less time and effort were required for performance of the IFA/LAPS assay. More importantly, use of genetically biotinylated scFv in the IFA/LAPS assay obviates the need for chemical biotinylation of antibody with resultant possible impairment of the antigen-binding site. Furthermore, the potential for batch-to-batch variability resulting from inequality in the number of biotin molecules labeled per antibody molecule is eliminated.     

Association of HLA antigens with differential responsiveness toMycobacterium w vaccine in multibacillary leprosy patients

Leprosy patients undergoing phase II trials in two hospitals of New Delhi, India, were HLA typed to see the association of HLA with differential responsiveness toMycobacterium w vaccine. The vaccine comprises an atypical, nonpathogenic mycobacterium,Mycobacterium w, which has cross-reactive antigens withM. leprae. Multibacillary patients who are lepromin negative are vaccinated at an interval of 3 months. Considerable improvement is evident in the patients in terms of a decline in bacterial indices and histopathological and immunological upgrading. But all the patients do not respond to the vaccine in the same manner; some are slow responders, while others are good responders. HLA-A28 and DQw3 (DQw8+9) were found to be associated with slow responsiveness, while DQw1 and DQw7 were found to be associated with a more rapid responsiveness to theM. w vaccine. However, these associations were not significant afterP correction for the number of antigens tested for each locus except for HLA-DQw3 (DQw8 and DQw9) and DQw7. DQw7, a new defined split of HLA-DQw3, seems to be associated with the responsiveness toM. w vaccine.     

Production of interleukin-1 and tumor necrosis factor by bone marrow-derived macrophages: effect of cisplatin and lipopolysaccharide

Mature macrophages derived in vitro from bone marrow progenitors under the influence of either L929 CM (a source of M-CSF) or GM-CSF have been shown to differ morphologically and functionally. Treatment of these bone marrow-derived macrophages with cisplatin or LPS resulted in the expression of enhanced tumoricidal activity and the production of significant amounts of extracellular and membrane-associated IL-1 and TNF. rGM-CSF-derived bone marrow macrophages produced higher amounts of TNF and IL-1 activity than L929CM-derived macrophages. Untreated bone marrow-derived macrophages showed little IL-1 and TNF activity. Bone marrow macrophages cultured with medium alone also did not respond to cisplatin or LPS for the production of IL-1 and TNF. Neutralization studies with anti-IL-1 and anti-TNF antibodies inhibited the IL-1 and TNF activity of bone marrow-derived macrophages. These results suggest that cisplatin or LPS treatment of murine bone marrow-derived macrophages results in increased expression of both released and membrane-associated IL-1 and TNF.     

Ascorbic acid metabolism in rats and guinea pigs after the administration of ethanol

Ascorbic acid metabolism was studied in guinea pigs and rats after the administration of ethanol and a high dose of ascorbic acid (AA). Male guinea pigs were maintained for 30 days as follows: (1) controls (1 mg AA/100 g body wt.); (2) ethanol (1 mg AA/100 g body wt. + 900 mg ethanol/100 g body wt); (3) ascorbic acid (25 mg AA/100 g body wt.); (4) ascorbic acid + ethanol (25 mg AA/100 g body wt. + 900 mg ethanol/100 g body wt.). Rats were also grouped into four groups as in the case of guinea pigs, but the dose of AA was 200 mg/100 g body weight. Rats adjusted to ethanol intoxication by enhancing the biosynthesis of ascorbate as evidenced by elevated activity of L-gulono lactone oxidase (GLO). Hence ascorbate levels were not lowered in rats after administration of alcohol. However, alcohol administration lowered tissue levels of ascorbate in guinea pigs. But the supplementation of ascorbate along with alcohol raised the tissue level of this vitamin. Guinea pigs responded to the ascorbate deficiency during alcohol administration by lowering the degradation of ascorbate, as seen by the lower activity of the degrading enzyme gulono lactone hydrolase. It is concluded that on the administration of alcohol, guinea pigs are dependent upon additional exogenous supplies of ascorbic acid, whereas rats are not.