Seed coat tannins and bruchid resistance in stored cowpea seeds

Seeds of wild species and varieties of Vigna were screened for their tannins and α‐amylase inhibitor contents as defensive compounds against cowpea weevil. Seed coats contained condensed tannins that were positively correlated to their colour but not to their resistance against the insect. The α‐amylase inhibitors were present in different amount in cotyledons of all species analysed. Amongst the cultivated lines assayed, Vigna unguiculata TVu 2027, an accession identified as moderately resistant, was found to contain the higher amount of α‐amylase inhibitor. When wild species were considered, V luteola and V vexillata (two resistant species) showed the highest content of α‐amylase inhibitors. In addition, two cultivated accessions (Vita 7 and IT 84E‐1‐108) of cowpea seeds, both classified as susceptible accessions, showing a different degree of bruchid damage in storage, were also analysed. No α‐amylase inhibitory activity was found in cotyledons of undamaged Vita 7 seeds, while the seed coat tannin content was found to be 13 times higher in undamaged Vita 7 seeds than in IT 84E‐1‐108 infested seeds. These latter results support the hypothesis that seed coat tannins must also be considered in biochemical defence mechanisms, which can deter, poison or starve bruchid larvae that feed on cowpea seeds. Copyright © 2004 Society of Chemical Industry     

CdO-based nanostructures as novel CO(2) gas sensors

Crystalline Cd(OH)(2)/CdCO(3) nanowires, having lengths in the range from 0.3 up to several microns and 5-30 nm in diameter, were synthesized by a microwave-assisted wet chemical route and used as a precursor to obtain CdO nanostructures after a suitable thermal treatment in air. The morphology and microstructure of the as-synthesized and annealed materials have been investigated by scanning electron microscopy, transmission electron microscopy, x-ray diffraction and thermogravimetry-differential scanning calorimetry. The change in morphology and electrical properties with temperature has revealed a wire-to-rod transformation along with a decreases of electrical resistance. Annealed samples were printed on a ceramic substrate with interdigitated contacts to fabricate resistive solid state sensors. Gas sensing properties were explored by monitoring CO(2) in synthetic air in the concentration range 0.2-5 v/v% (2000-50?000 ppm). The effect of annealing temperature, working temperature and CO(2) concentration on sensing properties (sensitivity, response/recovery time and stability) were investigated. The results obtained demonstrate that CdO-based thick films have good potential as novel CO(2) sensors for practical applications.     

Bacteriocin-producing Enterococcus casseliflavus IM 416K1, a natural antagonist for control of Listeria monocytogenes in Italian sausages ("cacciatore")

The bacteriocinogenic Enterococcus casseliflavus IM 416K1 (Bac+) isolated from Italian sausages or its bacteriocin Enterocin 416K1, with strong anti-listerial activity, were used in trials to evaluate the effect on Listeria monocytogenes NCTC 10888 in artificially inoculated Italian sausages ("cacciatore"). In trials with Enterocin 416K1 added, L. monocytogenes showed a significant reduction as compared to the control inoculated with L. monocytogenes alone. The elimination of L. monocytogenes was only obtained in sausages added with E. casseliflavus IM 416K1 Bac+.     

Mapping of genes predisposing to idiopathic generalized epilepsy

Idiopathic generalized epilepsy (IGE) is characterized by recurring generalized seizures in the absence of detectable brain lesions and/or metabolic abnormalities. Twin and family studies suggest that genetic factors play a key part in IGE. A multilocus model appears to best fit the observed inheritance patterns. Mapping of IGE-related genes has been previously attempted using parametric methods, with conflicting results. In particular, recent evidence argues both for and against a chromosome 6p locus (EJM1) for juvenile myoclonic epilepsy, a subtype of IGE. We have approached the problem of mapping IGE loci using non-parametric methods, which have recently been successful for other complex diseases. No evidence for linkage to chromosome 6p was obtained. However, we obtained evidence for involvement of a locus at chromosome 8q24, close to the marker D8S256. The same 8q24 region was previously implicated in families with benign neonatal familial convulsions (BNFC), a generalized epilepsy syndrome that is inherited as a simple dominant mendelian trait. There is an apparent conserved syntenic group of genes in human 8q24 and a region of mouse chromosome 15, which harbors the stargazer (stg) locus. Homozygous mutant mice at the stg locus show a form of generalized epilepsy that resembles human absence epilepsy. Our findings may have implications for a locus on 8q24 predisposing to IGE.     

Effect of propionyl-l-carnitine and enalapril on cardiac function of pressure-overloaded rats during increase in load

The c-met oncogene encodes the receptor for hepatocyte growth factor/scatter factor, a potent mitogen for epithelial cells that also promotes cell motility and invasiveness. We have studied the changes of c-met gene expression that occur during the progression of colorectal tumors. Sixteen adenomas, 123 primitive carcinomas, and 25 liver metastases were examined. In several instances it was possible to compare same-patient samples of normal colon mucosa against primary tumor and primary carcinoma against synchronous metastasis. The expression of the c-met gene was increased from 5- to 50-fold in about 50% of tumors, at any stage of progression, and in 70% of liver metastases. Overexpression was associated with amplification of the c-met gene in only 10% of carcinomas, but in 8 of 9 metastases examined. These data suggest that overexpression of the c-met oncogene contributes a selective growth advantage to neoplastic colorectal cells at any stage of tumor progression. Moreover, amplification appears to give a further selective advantage for the acquisition of metastatic potential.     

Randomized trial of CVPP for three versus six cycles in favorable-prognosis and CVPP versus AOPE plus radiotherapy in intermediate-prognosis untreated Hodgkin's disease

PURPOSE: To evaluate in a randomized trial the impact of three versus six cycles of cyclophosphamide, vinblastine, procarbazine, and prednisone (CVPP) chemotherapy in favorable-prognosis and CVPP versus doxorubicin, vincristine, prednisone, and etoposide (AOPE) plus involved-field radiotherapy (RT) in intermediate-prognosis previously untreated Hodgkin's disease. PATIENTS AND METHODS: Of 256 patients evaluated, 80 with a favorable prognosis according to a prognostic index designed by the Grupo Argentina de Tratamiento de Leucemia Aguda (GATLA) were randomized to three versus six cycles of CVPP without RT and 176 with intermediate risk to CVPP versus AOPE, both for six cycles with RT between the third and fourth cycles of 30 Gy to the involved areas at diagnosis. CVPP consisted of intravenous (I.V.) cyclophosphamide and vinblastine on days 1 and 8, and oral procarbazine and prednisone on days 1 to 14, every 28 days. AOPE consisted of I.V. doxorubicin and vincristine on day 1, oral prednisone on days 1 to 5, and I.V. etoposide on days 1 and 3, every 28 days. RESULTS: Complete remission was obtained in 39 of 41 (95%) patients treated with three cycles of CVPP and 36 of 39 (92%) treated with six cycles in the favorable-risk group (difference not significant [NS]). In the intermediate-risk group, 89 of 92 (97%) treated with CVPP plus RT versus 75 of 84 (89%) treated with AOPE plus RT achieved a complete remission (P = .05). At 60 months, the event-free survival (EFS) and overall survival rates in the favorable-risk group were 80% and 91% for CVPP x 3 and 84% and 97% for CVPP x 6, respectively (P = NS). In the intermediate-risk group, 60-month EFS rate for CVPP plus RT was 85%, compared with 66% for AOPE plus RT (P = .009). The overall survival rate was 95% versus 87% respectively (P = .157). CONCLUSION: Three cycles of CVPP without RT are equally effective as six cycles in the favorable-risk group. However, in the intermediate-group, CVPP plus RT is superior to AOPE plus RT, with significantly fewer events before and after induction (P = .009), without a difference in overall survival.     

Full-wave analysis of photonic bandgap integrated optical components by the TLM-IE method

This paper presents the full-wave analysis of commonly encountered optical periodic structures by the novel transmission-line matrix/integral equation (TLM-IE) method. The TLM-IE is a three-dimensional full-wave hybrid technique that combines the advantages of the numerical TLM method in dense finite regions and those of the IE method in open regions where simple Green functions are available. The pre- and postprocessing tools of the TLM-IE solver provide visualization and physical insight into the dynamics of electromagnetic propagation in such devices. The aim of this effort is twofold: 1) to analyze the diffraction and reflection characteristics of photonic bandgap gratings and 2) to define optimization guidelines for the Q factor of integrated dielectric resonators.     

Hydrogenation of phenol to cyclohexanone over Pd/MgO

Hydrogenation of phenol to cyclohexanone has been investigated in the temperature range 160–250°C on a series of Pd/MgO catalysts. At 160°C the orders of reaction were found on all catalysts to be about ?1 with respect to phenol and about + 1 with respect to hydrogen. On the basis of the kinetic results it is suggested that the rate determining step is the surface reaction between phenol and hydrogen adsorbed on the catalyst. An increase in the reaction temperature decreases the rate of reaction. This has been explained through a change of the orders of reaction which increase with temperature. Palladium dispersion does not influence the reaction mechanism. The specific activity was found to be independent of palladium particle size.