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1.
By immunological and biochemical methods a biotin-binding protein, distinct from avidin, has been shown to be present in chicken egg white. This vitamin-binding protein (Mr 67,000) bound [14C]biotin, displayed thermally induced biotin exchange reaction and exhibited gross immunological cross-reactivity with the purified yolk biotin-binding protein. In vitro labelling of soluble proteins with radioactive amino acids in the oviduct tissue explants from estrogenised chicks revealed that approx. 2% of the total radioactive proteins was immunoprecipitated with anti-yolk biotin-binding protein antibodies. The protein could be purified to homogeneity by employing ion-exchange chromatography on DEAE-cellulose and biotin-AH Sepharose affinity chromatography. The purified protein specifically bound [14C]biotin, and exhibited complete immunological homology with the yolk biotin-binding protein but not with avidin. Its electrophoretic mobility (at pH 8.3), acidic nature, biotin-binding characteristics, immunological cross-reactivity and tryptic peptide maps were very similar to that of yolk biotin-binding protein, and not avidin.  相似文献   
2.
Baculovirus recombinants expressing a neurotoxin gene,tox34,from the straw itch mitePyemotes triticihave been previously shown to paralyze or kill insects approximately 50% faster than wild-type. We constructed a series of recombinants of the baculovirusAutographa californicanucleopolyhedrovirus which expressedtox34with different signal sequences or were controlled by different promoters to evaluate their influence on toxin expression in cell culture and in insects. Heterologous signal sequences provided no significant increase in the overall levels of the maturetox34gene product, Tox34, secreted into the tissue culture media from infected cells and no improvement in the time required for paralysis of insect hosts. The time required for paralysis was promoter-dependent; the late 6.9K DNA binding protein gene promoter was generally the most effective promoter, although an insect HSP70 promoter was equally or more effective in one of the species.  相似文献   
3.
Ilisha kampeni (Pisces Clupeidae) is described based on new material from Bombay and Kakinada. The species was originally described as Pellona kampeni from Java and Borneo. Samples of I. kampeni from Bombay (west coast) and Kakinada (east coast) are compared, using t test and Chi-square test for meristic characters and multivariate analysis for body measurements. Significant differences observed in 6 of the 12 meristic characters and all the 6 body measurements indicate that the samples from Bombay and Kakinada belong to different stocks.  相似文献   
4.
Novel 1,2-diaryl-1-ethanone 1 and pyrazolo [4,3-c] quinoline-4-one 2, with pharmacophores different from the known COX inhibitors were identified as selective COX-2 inhibitors. The communication briefly describes SAR of both the series.  相似文献   
5.
Several 2,3-diaryl pyrazines and quinoxalines with 4-sulfamoyl (SO(2)NH(2))/methylsulfonyl (SO(2)Me)-phenyl pharmacophores have been synthesized and evaluated for the cyclooxygenase (COX-1/COX-2) inhibitory activity. Smaller groups such as methoxy, methyl and fluoro when substituted at/around position-4 of the adjacent phenyl ring, have great impact on the selective COX-2 inhibitory activity of the series. Many potential compounds were obtained from a brief structure-activity relationship (SAR) study. Two of these, compounds 11 and 25 exhibited excellent in vivo activity in the established animal model of inflammation. Since compound 25 possessed an amenable sulfonamide group, two of its prodrugs 48 and 49 were also synthesized. Both of them have excellent in vivo potential, and represent a new class of COX-2 inhibitor.  相似文献   
6.
We describe an approach to analyzing single- and multiunit (ensemble) discharge patterns based on information-theoretic distance measures and on empirical theories derived from work in universal signal processing. In this approach, we quantify the difference between response patterns, whether time-varying or not, using information-theoretic distance measures. We apply these techniques to single- and multiple-unit processing of sound amplitude and sound location. These examples illustrate that neurons can simultaneously represent at least two kinds of information with different levels of fidelity. The fidelity can persist through a transient and a subsequent steady-state response, indicating that it is possible for an evolving neural code to represent information with constant fidelity.  相似文献   
7.
In our endeavor to design and synthesize novel anticancer agents, a new series of indoloquinazoline compounds were prepared and tested initially for anticancer activity in vitro against a panel of human cancer cell lines. Most of these compounds exhibited cytotoxic activity in in vitro screens. Compounds were selected and further evaluated using a modified Hollow Fiber Assay for their preliminary in vivo activity against 12 cell lines implanted in the subcutaneous and intraperitoneal compartments in mice. The results indicate that these compounds may constitute a new class of anticancer agents.  相似文献   
8.
To improve efficiency of transgenesis, we compared M16 and CZB embryo culture media, supporting development to blastocysts of FVB/N mouse pronuclear-eggs, microinjected with enhanced green fluorescent protein (EGFP) transgene. When EGFP-injected-eggs were cultured (120 hr), blastocyst development was significantly (P < 0.03) higher in M16 medium (72.5 +/- 2.4%) than that in CZB (13.2 +/- 4.3%) or CZBG (CZB with 5.6 mM glucose at 48 hr culture) (62.1 +/- 3.7%) media. Blastocyst development of noninjected embryos was higher in M16 (92.0 +/- 2.6%) and CZBG (83.9 +/- 3.9%) media than in CZB (31.9 +/- 2.8%) medium (P < 0.0001). However, percentages of morulae at 72 hr were comparable in all treatments. Developed blastocysts were better in M16 than in CZB or CZBG media. Consistent with this, mean cell number per blastocyst, developed from injected embryos, was significantly (P < 0.002) higher in M16 medium (79.6), than those in CZB (31.3) or CZBG media (60.7); similar with noninjected embryos. Cell allocation to trophectoderm (TE) and inner cell mass (ICM), i.e., TE:ICM ratio, for injected blastocysts in M16 (3.0) was less than (P < 0.05) those in CZB (4.2) and CZBG (4.4) media; similar with noninjected blastocysts. Moreover, blastocysts, developed in M16 and CZBG media, hatched, attached, and exhibited trophoblast outgrowth; 18% of them showed EGFP-expression. Importantly, blastocysts from M16 medium produced live transgenic "green" pups (11%) following embryo transfer. Taken together, our results indicate that supplementation of glucose, at 48 hr of culture (CZBG), is required for morula to blastocyst transition; M16 medium, containing glucose from the beginning of culture, is superior to CZB or CZBG for supporting development of biologically viable blastocysts from EGFP-transgene-injected mouse embryos.  相似文献   
9.
Caspases are cysteine proteases essential to apoptosis. We have identified two families of caspase-like proteins, Paracaspases (found in metazoans and Dictyostelium) and metacaspases (found in plants, fungi, and protozoa). Metazoan paracaspase prodomains contain a death domain and immunoglobulin domains. Several plant metacaspase prodomains contain zinc finger motifs resembling those in the plant hypersensitive response/cell death protein Isd-1. The human paracaspase prodomain binds Bcl10, a protein involved in the t(1;14)(p22;q32) translocation of mucosa-associated lymphoid tissue (MALT) lymphoma. Another MALT lymphoma translocation, t(11;18)(q21;q21), fuses the IAP-2 gene to the MLT1/MALT1 locus, which encodes the human paracaspase. We find that this fusion activates NF-kappaB and that the caspase domain is required for this function, since mutation of the conserved catalytic cysteine attenuates NF-kappaB activation.  相似文献   
10.
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