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21.
Baculovirus chitinase gene (chiA) is a late gene essential for liquefying the host insect at a late stage of infection for its hydrolyzing chitin function. In a previous report, baculovirus ChiA has been shown to offer many interesting new opportunities for pest control. Recently, a putative chiA gene was identified in the Korean isolate of the Spodoptera litura nucleopolyhedorvirus (SpliMNPV‐K1) genome. The open reading frame (ORF) contains 1692 nucelotides and encodes a protein of 563 amino acids with a predicted molecular weight of about 62.6 kDa. To study the insecticidal activity of ChiA from SpliMNPV‐K1, we constructed a recombinant AcMNPV, Ap‐SlChiA, which is designed to express the ChiA under the control of a polyhedrin promoter. Western blot analysis indicated that ChiA was successfully expressed by this recombinant virus. Chitinase assay revealed that the chitobiosidase and endochitinase activity of the recombinant virus was 2.5‐ and 3.9‐flods higher than those of wild‐type AcMNPV, respectively. In addition, the recombinant virus showed higher evident insecticidal activity against 3rd instar larvae of Spodotera exigua than that of the AcMNPV. These results suggest that the chiA gene from SpliMNPV‐K1 could be successfully applied to improve pathogenicity of baculoviruses.  相似文献   
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Kwon Y  Chi P  Roh DH  Klein H  Sung P 《DNA Repair》2007,6(10):1496-1506
Rad54, a member of the Swi2/Snf2 protein family, works in concert with the RecA-like recombinase Rad51 during the early and late stages of homologous recombination. Rad51 markedly enhances the activities of Rad54, including the induction of topological changes in DNA and the remodeling of chromatin structure. Reciprocally, Rad54 promotes Rad51-mediated DNA strand invasion with either naked or chromatinized DNA. Here, using various Saccharomyces cerevisiae rad51 and rad54 mutant proteins, mechanistic aspects of Rad54/Rad51-mediated chromatin remodeling are defined. Disruption of the Rad51-Rad54 complex leads to a marked attenuation of chromatin remodeling activity. Moreover, we present evidence that assembly of the Rad51 presynaptic filament represents an obligatory step in the enhancement of the chromatin remodeling reaction. Interestingly, we find a specific interaction of the N-terminal tail of histone H3 with Rad54 and show that the H3 tail interaction domain resides within the amino terminus of Rad54. These results suggest that Rad54-mediated chromatin remodeling coincides with DNA homology search by the Rad51 presynaptic filament and that this process is facilitated by an interaction of Rad54 with histone H3.  相似文献   
24.
Hypothalamic inflammation has been known as a contributor to high-fat diet (HFD)-induced insulin resistance and obesity. Myeloid-specific sirtuin 1 (SIRT1) deletion aggravates insulin resistance and hypothalamic inflammation in HFD-fed mice. Neurogranin, a calmodulin-binding protein, is expressed in the hypothalamus. However, the effects of myeloid SIRT1 deletion on hypothalamic neurogranin has not been fully clarified. To investigate the effect of myeloid SIRT1 deletion on food intake and hypothalamic neurogranin expression, mice were fed a HFD for 20 weeks. Myeloid SIRT1 knockout (KO) mice exhibited higher food intake, weight gain, and lower expression of anorexigenic proopiomelanocortin in the arcuate nucleus than WT mice. In particular, KO mice had lower ventromedial hypothalamus (VMH)-specific neurogranin expression. However, SIRT1 deletion reduced HFD-induced hypothalamic neurogranin. Furthermore, hypothalamic phosphorylated AMPK and parvalbumin protein levels were also lower in HFD-fed KO mice than in HFD-fed WT mice. Thus, these findings suggest that myeloid SIRT1 deletion affects food intake through VMH-specific neurogranin-mediated AMPK signaling and hypothalamic inflammation in mice fed a HFD.  相似文献   
25.
We cloned and expressed a full-length cDNA encoding a phospholipase D of type alpha (PLDalpha) from cabbage. Analysis of the cDNA predicted an 812-amino-acid protein of 92.0 kDa. The deduced amino acid sequence of cabbage PLD has 83% and 80% identity with Arabidopsis PLDalpha and castor bean PLD, respectively. Expression of this cDNA clone in E. coli shows a functional PLD activity similar to that of the natural PLD.  相似文献   
26.
Radical paring of the cleft edge during a primary cleft operation or repeated secondary surgeries can result in tightness of the upper lip. The degree of the resulting side-to-side tension can vary, from mild cases for which improvement is sought through realignment of the misplaced oral sphincter muscle in secondary revision, to severe cases for which the possibility of a lip switch flap must be considered. When the lip tightness accompanies more than three-quarters loss of the Cupid's bow, an Abbé flap is an alternative. However, the lip switch flap is far from ideal, in both artistic and functional perspectives, and should be avoided if at all possible in mild to moderate degrees of lip tightness. This study presents a method of correcting horizontal cleft upper lip tightness, especially of the vermilion. The method involves local transfer of an inferiorly based rectangular flap from the relatively redundant upper two-thirds to the lower one-third of the upper lip and vermilion. Primary indications for the technique include vermilion tightness with half to three-quarters loss of Cupid's bow. The method has the advantage of supplementing the horizontal lip dimension on the cleft side and restoring a natural Cupid's bow, thereby repositioning the shifted philtral column and adding fullness to the lower one-third of the upper lip. Incorporation of the upper lip scar in the rectangular flap removes ugly scars and spares the lower lip from surgical violation. The orbicularis sphincter function, as seen in facial animation, was well regained. Twenty unilateral and three bilateral cases with a maximal follow-up period of 4.5 years are presented.  相似文献   
27.
Bacillus thuringiensis 656-3, isolated from a soil sample collected at mushroom houses, showed high toxicity to mushroom flies, Lycoriella mali and Coboldia fuscipes. B. thuringiensis 656-3 produced bipyramidal inclusions and reacted with the H antiserum of B. thuringiensis subsp. morrisoni (H8a8b). The plasmid and protein profiles of B. thuringiensis 656-3 were similar to those of its reference strain, subsp. morrisoni PG-14. However, PCR analysis using cry gene primers showed that B. thuringiensis 656-3, unlike its reference strain, had cry4A, cry4B, cry10A, cry11A, and cry1Ac genes, suggesting that B. thuringiensis 656-3 was a unique strain with respect to gene type. In addition, B. thuringiensis 656-3 showed a high level of toxicity against mushroom flies, L. mali and C. fuscipes.  相似文献   
28.
We report full-term development of nuclear transfer embryos following nuclear exchange at the 2-cell stage. Nuclei from 2-cell rat embryos were transferred into enucleated 2-cell embryos and developed to term after transfer to recipients (NT2). Pronuclear exchange in zygotes was used for comparison (NT1). Zygotes and 2-cell embryos were harvested from 4-week-old female Sprague-Dawley rats. Nuclear transfer was performed by transferring the pronuclei or karyoplasts into the perivitelline space of recipient embryos followed by electrofusion to reconstruct embryos. Fused couplets were cultured for 4 or 24 h before being transferred into day 1 pseudopregnant recipients (Hooded Wistar) at the 1- or 2-cell stage. In vitro culture was also carried out to check the developmental competence of the embryos. In vitro development to the blastocyst stage was not significantly different between the two groups (NT1, 34.3%; NT2, 45.0%). Two of three recipients from NT1 and two of five recipients from NT2 became pregnant. Six pups (3 from NT1, 3 from NT2) were delivered from the four foster mothers. Three female pups survived; 2 from NT1 and 1 from NT2. At 2 months of age these pups appeared healthy, and were mated with Sprague-Dawley males. One rat derived from NT1 delivered 15 pups (5 males, 10 females) as did the rat from NT2 (7 males, 8 females). Our results show that by using karyoplasts from 2-cell stage embryos as nuclear donors and reconstructing them with enucleated 2-cell embryos, healthy rats can be produced.  相似文献   
29.
Pituitary adenylate cyclase activating polypeptide (PACAP) was first isolated from ovine hypothalamus and is known to act as a tropic factor in various cells. Recent report revealed the expression of PACAP and the PACAP type I (PAC(1)) receptor in human and rat placentas at term. Placenta is a critical organ that synthesizes several growth and angiogenic factors for its own growth as well as fetal development. However, there is little information regarding the expression pattern and cellular localization of PACAP and PAC(1) during pregnancy. The aim of this study was to define the expression and distribution of PACAP and PAC(1) receptor mRNAs in the rat placenta during pregnancy. PACAP and PAC(1) receptor mRNAs were expressed in decidual cells, chorionic vessels, and stromal cells of the chorionic villi. Interestingly, the expression of these genes varied with the day of gestation. For example, PACAP and PAC(1) receptor mRNAs expressed in decidual cells on day 13.5 and 15.5, their expression was strong in chorionic vessels and stromal cells of the chorionic villi within the labyrinth zone on day 17.5, 19.5, and 21.5. In fact, as gestation advanced, the expression of PACAP and PAC(1) receptor mRNAs in the decidua cells disappeared, as their high expression became evident in the chorionic vessels and stromal cells of the chorionic villi. Our finding that PACAP and the PAC(1) receptor are co-localized and their genes seemingly co-regulated within specific placental areas, strongly suggest that this peptide may play an important role, as an autoregulator or pararegulator via its PAC(1) receptor, in physiological functioning of the placenta for gestational maintenance.  相似文献   
30.
Total ear reconstruction by the use of contralateral temporoparietal fascial free flap and autogenous costal cartilage was performed in 16 patients presenting with a devascularized temporoparietal region resulting from trauma or prior surgery. The microsurgical success rate was 87.5 percent (14 of 16 transplants). On evaluation of the final aesthetic result in 11 patients followed up for more than 3 years, nine patients were graded good-to-excellent and two patients exhibited fair-to-poor results. Despite the relatively long operating hours and the comparatively low microsurgical success rate, ear reconstruction by autogenous tissue transplantation has proved to be an encouraging and worthwhile experience. This article presents the clinical cases and discusses the technical details.  相似文献   
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