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603.
Using the Adeno-associated virus (AAV) as a gene
delivery vehicle, we have constructed a recombinant
vector containing the full length rat preproinsulin
gene (vLP-1). Utilizing the well described non-obese
diabetic (NOD) mouse model, an experimental
group (n=10) of animals were intramuscularly (IM)
injected with 107 rAAV virions containing the
insulin gene and compared to a mock-injected control
group (n=10). Blood glucose (glc) was then
measured weekly for 16 weeks. Data showed that
the experimental group contained 70% euglycemic
animals (defined as glc <200mg/dL) versus 10% of
the control animals (P<.05) at 14 weeks. Mean
weight in the treated group was greater than the
untreated group. Insulin mRNA was detected at the
injection site of all of the treated animals, but not
controls. Complete destruction of islets was confirmed
by histology ruling out the possibility of
spontaneous reversal of insulinitis. We conclude
that IM delivery of the insulin gene in the NOD
mouse was able to prevent clinical DM up to 14
weeks in a majority of treated animals. Our experimental
data suggests that gene therapy may be an
alternative treatment for IDDM in the future. 相似文献
604.
Abstract Field observations were carried out between 2002 and 2005 on bio‐ecology of white grubs infesting teak (Tectona grandis Linn. f.) seedlings at Ramdongari Forest Nursery, Forest Development Corporation of Maharashtra, Nagpur in central India. The study collected the data required for an integrated pest management strategy against the white grubs. The species damaging teak seedlings were Holotrichia rustica (Burmeister) and H. mucida Gyllenhal. The beetles (adults) of both these species began to emerge just after the pre‐monsoon showers and when the relative humidity had risen rapidly over several days, but before the first monsoon rains. While the adults fed and mated on naturally growing bushes of Ziziphus jujuba, Z. mauritiana, Z. xylopyra, Acacia leucophloea and A. catechu immediately after the emergence from the teak beds in the nursery, the immature stages (grubs) of both species fed on roots of the teak seedling, leading to plant death. This is the first report of (i) damage caused to teak seedlings by grubs of H. rustica and H. mucida, and (ii) of Z. jujuba and Z. mauritiana being hosts for the beetles of H. mucida and H. rustica. It is also the first detailed report on the field bio‐ecology of the H. rustica and H. mucida as major pests of teak. White grubs are among the toughest‐to‐manage pests of economic importance and information presented here on the pest incidence and damage of H. rustica and H. mucida is important to researchers and nursery field managers for the management of these pests on teak. 相似文献
605.
pH-Dependence of hydrolytic activity of trypsin has been studied in cationic reverse micellar system of cetyltrimethylammonium bromide (CTAB) in (50% v/v) chloroform/isooctane using a positively charged substrate Nα-benzoyl-L-arginine ethyl ester (BAEE). The pH of the medium was varied from 4.0 to 8.5 with addition of 0.025 M citrate-phosphate buffer containing 1 mM CaCl2. Optimum pH for maximum enzyme activity, pHopt in reverse micelles is found to be similar to that observed in bulk aqueous solution (8.0–8.5). However, changes in activity of trypsin (kcat) as a function of water content W0 (W0 = [H2O]/[CTAB]) in reverse micelles are found to be pH dependent. At low pH (4.0) and low water content (W0 = 5) the enzyme is more active in reverse micelles than in bulk aqueous solution by a factor of 2. This ‘superactivity’ is lost at higher W0 values and the kcat in reverse micelles is found to be similar to that observed in aqueous bulk. At pH 5, the enzyme activity is found to be independent of W0 while at pH 6.0–6.5 the enzyme activity is low at W0 5 and increases with water content to a constant value which is still 50% lower than that in aqueous buffer. Above pH 7, the Wo-activity profile becomes distinctly bell shaped with W0 optimum around 10–15. The enzyme activity at optimum W0 is close to that observed in aqueous bulk. 相似文献