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61.
62.
Halieutopsis bathyoreos Bradbury, 1988 (Lophiiformes: Ogcocephalidae), previously described only on the basis of the holotype (62.6mm in standard length) from the central North Pacific, is redescribed on the basis of the holotype and six additional specimens (41.2–68.7mm in standard length) collected from the western South Pacific, off Papua New Guinea, and the western North Pacific, including the Japanese Archipelago. Halieutopsis bathyoreos is distinguished from its congeners by having a shelflike rostrum extending anteriorly well beyond the mouth, a dorsal escal lobe slightly bisected ventrally, an illicial cavity square in outline and completely visible in ventral view, and lacking tubercles on the ventral surface of the disk. The following characters are newly added to the diagnoses of this species: rostrum width 21–29% of head length, tubercles on the dorsal surface of the disk about half the diameter of those on the lateral margin, and 13–15 large lateral-line scales on the tail.  相似文献   
63.
Poly[(R)-3-hydroxybutyrate] (PHB) depolymerases adsorbed on poly(L-lactide) (PLLA) thin film were directly observed by atomic force microscopy (AFM). A PLLA thin film of 100 nm thickness was prepared on a silicon wafer by spin-cast method. The PLLA thin film was treated at 220 degrees C and quenched to room temperature, resulting in the formation of a completely amorphous film with a smooth surface. Then, the PHB depolymerases from Pseudomonas stutzeri YM1006 and Ralstonia pickettii T1 were dispersed on the amorphous PLLA thin film. Direct AFM observation has revealed that the PHB depolymerases bind in an elliptic shape on the surface of the PLLA thin film and that a small ridge is created around each enzyme molecule. After removal of the enzymes with 40% ethanol aqueous solution, small hollows were found on the PLLA thin film. These results suggest that a PHB depolymerase interacts with polyester molecules during their adsorption to make a hollow on the substrate surface.  相似文献   
64.
A series of novel curcumin analogs were synthesized and screened for anti-cancer and anti-angiogenesis activities at Emory University and at the National Cancer Institute (NCI). These compounds are symmetrical alpha,beta-unsaturated and saturated ketones. The majority of the analogs demonstrated a moderate degree of anti-cancer activity. Compounds 10, 11, and 14 exhibited a high degree of cytotoxicity in the NCI in vitro anti-cancer cell line screen. In addition, this screen revealed that these compounds inhibit tumor cell growth with a higher potency than the commonly used chemotherapeutic drug, cisplatin. In independent in vitro screens conducted at Emory, the same compounds plus 4, 5, 8, 9, and 13 exhibited a high degree of cytotoxicity to tumor cells. Analogs that were effective in the anti-cancer screens were also effective in in vitro anti-angiogenesis assays. Compounds 4, 9, 11, and 14 were most effective in the anti-angiogenesis assays run at Emory. In the assays conducted by the NCI, compound 14 was almost as potent as the anti-angiogenic drug TNP-470, which has undergone clinical trials. Based on the favorable in vitro anti-cancer and anti-angiogenesis results with 14, further in vivo tests were conducted. This compound effectively reduced the size of human breast tumors grown in female athymic nude mice and showed little toxicity. This data, coupled with the remarkable in vitro data, suggests that compound 14 may potentially be an effective chemotherapeutic agent. As a follow-up, a 3D quantitative structure relationship based on 14 has been developed. It shows a cross-validated r2(q2) and a predictive r2(p2) = 0.71. COMPARE analysis suggests the compound to be a possible RNA/DNA antimetabolite, but also implies that the compound's cytotoxicity may arise from a presently unknown mechanism.  相似文献   
65.
Methionine aminopeptidase, known to be encoded by single genes in prokaryotes, is a cobalt-dependent enzyme that catalyzes the removal of N-terminal methionine residues from nascent polypeptides. Three ORFs encoding putative methionine aminopeptidases from the genome of cyanobacterium Synechocystis sp. strain PCC6803, designated as slr0786 (map-1), slr0918 (map-2) and sll0555 (map-3) were cloned and expressed in Escherichia coli. The purified recombinant proteins encoded by map-1 and map-3 had much higher methionine aminopeptidase activity than the recombinant protein encoded by map-2. Comparative analysis revealed that the three recombinant enzymes differed in their substrate specificity, divalent ion requirement, pH, and temperature optima. The broad activities of the iso-enzymes are discussed in light of the structural similarities with other peptidase families and their levels of specificity in the cell. Potential application of cyanobacterial MetAPs in the production of recombinant proteins used in medicine is proposed. This is the first report of a prokaryote harboring multiple methionine aminopeptidases.Abbreviations map Gene encoding methionine aminopeptidase - MetAP Methionine aminopeptidase - eMetAP-Ia Escherichia coli methionine aminopeptidase type Ia - yMetAP-Ib Yeast methionine aminopeptidase type Ib - yMetAP-IIa Yeast methionine aminopeptidase type IIa - hMetAP-IIb Human methionine aminopeptidase type IIb - pfMetAP–IIa Pyrococcus furiosis methionine aminopeptidase type Ia - bst MetAP-Ia Bacillus stearothermophilus methionine aminopeptidase type Ia - c1MetAP-Ia Cyanobacterial methionine aminopeptidase type Ia encoded by map-1 - c2MetAP-Ia Cyanobacterial methionine aminopeptidase type Ia encoded by map-2 - c3MetAP-Ib Cyanobacterial methionine aminopeptidase type Ib, ncoded by map-3  相似文献   
66.
We previously demonstrated that sustained disturbance of endothelium-dependent vasorelaxation and poor distal runoff in ischemic limbs were critical factors affecting the neointimal development of autologous vein grafts (VGs). Also, we recently showed the superior therapeutic potential of basic fibroblast growth factor (bFGF/FGF-2) boosted by the recombinant Sendai virus (SeV) for severe limb ischemia compared with that of vascular endothelial growth factor. Here, the effect of FGF-2 on neointimal hyperplasia of VGs was examined in a rabbit model of poor-runoff limbs. Two weeks after initial surgery for the induction of poor-runoff, SeV-expressing human FGF-2 (SeV-hFGF2) or that encoding firefly luciferase (109 plaque-forming units/head) was injected into the thigh and calf muscle. At that time, the femoral vein was implanted in the femoral artery in an end-to-end manner in some groups. FGF-2 gene-transferred limbs demonstrated significantly increased blood flow assessed not only by laser Doppler flow image but also by ultrasonic transit-time flowmeter (USTF). USTF also showed a significant increase in the blood flow ratio of the deep femoral artery to external iliac artery, indicating that collateral flow was significantly restored in the thigh muscles (P < 0.01). Reduction of neointimal hyperplasia was also observed in the VGs treated by SeV-hFGF2; these grafts demonstrated significant restoration of endothelium-dependent vasorelaxation. These findings thus extend the indications of therapeutic angiogenesis using SeV-hFGF2 to include not only limb salvage but also prevention of late graft failure.  相似文献   
67.
CD4(+)CD25(+) regulatory T cells in normal animals are engaged in the maintenance of immunological self-tolerance and prevention of autoimmune disease. However, accumulating evidence suggests that a fraction of the peripheral CD4(+)CD25(-) T cell population also possesses regulatory activity in vivo. Recently, it has been shown glucocorticoid-induced TNFR family-related gene (GITR) is predominantly expressed on CD4(+)CD25(+) regulatory T cells. In this study, we show evidence that CD4(+)GITR(+) T cells, regardless of the CD25 expression, regulate the mucosal immune responses and intestinal inflammation. SCID mice restored with the CD4(+)GITR(-) T cell population developed wasting disease and severe chronic colitis. Cotransfer of CD4(+)GITR(+) population prevented the development of CD4(+)CD45RB(high) T cell-transferred colitis. Administration of anti-GITR mAb-induced chronic colitis in mice restored both CD45RB(high) and CD45RB(low) CD4(+) T cells. Interestingly, both CD4(+)CD25(+) and CD4(+)CD25(-) GITR(+) T cells prevented wasting disease and colitis. Furthermore, in vitro studies revealed that CD4(+)CD25(-)GITR(+) T cells as well as CD4(+)CD25(+)GITR(+) T cells expressed CTLA-4 intracellularly, showed anergic, suppressed T cell proliferation, and produced IL-10 and TGF-beta. These data suggest that GITR can be used as a specific marker for regulatory T cells controlling mucosal inflammation and also as a target for treatment of inflammatory bowel disease.  相似文献   
68.
We describe the development of novel lentivirus vectors based on simian immunodeficiency virus from African green monkey (SIVagm) pseudotyped with Sendai virus (SeV) envelope glycoproteins. SeV fusion (F) and hemagglutinin-neuraminidase (HN) proteins were successfully incorporated into the SIVagm-based vector by truncation of the cytoplasmic tail of the F protein and by addition of the cytoplasmic tail of SIVagm transmembrane envelope protein to the N terminus of the HN protein. As with the vesicular stomatitis virus G glycoprotein-pseudotyped vector, the mutant SeV F- and HN-pseudotyped SIVagm vector was able to transduce various types of animal and human cell lines. Furthermore, the vector was able to transduce an enhanced green fluorescent protein reporter gene into polarized epithelial cells of rat trachea from the apical and basolateral sides. Therefore, SeV F- and HN-pseudotyped SIVagm vectors have considerable potential for effective use in gene therapy for various therapies, including respiratory diseases.  相似文献   
69.
Polycation liposome-mediated gene transfer in vivo   总被引:2,自引:0,他引:2  
The polycation liposome (PCL), a recently developed gene transfer system, is simply prepared by a modification of liposomes with cetylated polyethylenimine (PEI), and shows remarkable transgene efficiency with low cytotoxicity. In the present study, we investigated the applicability of PCLs for in vivo gene transfer, since the PCL-mediated transgene efficiency was found to be maintained in the presence of serum. PCLs composed of dioleoylphosphatidylethanolamine (DOPE) with 5 mol% cetyl PEI (PEI average mr. wt. 1800), were superior for transfection to those of dipalmitoylphosphatidylcholine (DPPC) and cholesterol (2:1 as molar ratio) with 5 mol% cetyl PEI in vitro, although the latter PCLs were more efficient for gene transfer in vivo. PCL-DNA complexes were injected into mice via a tail or the portal vein, with the DNA being a plasmid encoding green fluorescent protein (GFP) or luciferase; and the expression was monitored qualitatively or quantitatively, respectively. Tail vein injection resulted in high expression of both GFP and luciferase genes in lung, and portal vein injection resulted in high expression of both genes in the liver. Concerning the gene delivery efficiency, the PCL was found to be superior to PEI or cetyl PEI alone. The optimal conditions for in vivo transfection with PCLs were also examined.  相似文献   
70.
Membrane-bound glucose dehydrogenase (mGDH) in Escherichia coli is one of the pivotal pyrroloquinoline quinone (PQQ)-containing quinoproteins coupled with the respiratory chain in the periplasmic oxidation of alcohols and sugars in Gram-negative bacteria. We compared mGDH with other PQQ-dependent quinoproteins in molecular structure and attempted to trace their evolutionary process. We also review the role of residues crucial for the catalytic reaction or for interacting with PQQ and discuss the functions of two distinct domains, radical formation in PQQ, and the presumed existence of bound quinone in mGDH.  相似文献   
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