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991.
A potentially heptadentate ligand H3L (N,N′-bis(2-hydroxybenzyl)-1,3-bis[(2-aminoethyl)amino]-2-propanol) and its two Ni(II) complexes, [Ni(H2L)H2O](H2O)3ClO4 (1) and [Ni(H2L)(H2O)](H2O)Cl (2) were prepared and characterized. X-ray structural analyses indicate that complex 1 has a distorted octahedral coordination geometry, with four amine N atoms of H2L− defining the equatorial plane, one aqua O atom and one phenoxo O atom of the ligand occupying two axial positions, respectively. The Ni(II) center of 2 has coordination geometry similar to that of 1. IR and electronic spectra of 1 and 2 are in agreement with their crystal structural features. Approximately along the ab plane, 2D supramolecular structure of 1 is assembled through multiple hydrogen bonds between hydroxy groups of the ligands, coordinated and crystal lattice H2O and π-π stacking interactions between adjacent phenyl rings of the ligands, while for that of 2, probably along the a axis, 1D chain structure is also formed by multiple hydrogen bonds, but lack of π-π stacking interactions. 相似文献
992.
Limited Protection from a Pathogenic Chimeric Simian-Human Immunodeficiency Virus Challenge following Immunization with Attenuated Simian Immunodeficiency Virus 下载免费PDF全文
Mark G. Lewis Jake Yalley-Ogunro Jack J. Greenhouse Terry P. Brennan Jennifer Bo Jiang Thomas C. VanCott Yichen Lu Gerald A. Eddy Deborah L. Birx 《Journal of virology》1999,73(2):1262-1270
Two live attenuated single-deletion mutant simian immunodeficiency virus (SIV) constructs, SIV239Δnef and SIVPBj6.6Δnef, were tested for their abilities to stimulate protective immunity in macaques. During the immunization period the animals were examined for specific immune responses and virus growth. Each construct generated high levels of specific immunity in all of the immunized animals. The SIV239Δnef construct was found to grow to high levels in all immunized animals, with some animals remaining positive for virus isolation and plasma RNA throughout the immunization period. The SIVPBj6.6Δnef was effectively controlled by all of the immunized animals, with virus mostly isolated only during the first few months following immunization and plasma RNA never detected. Following an extended period of immunization of over 80 weeks, the animals were challenged with a pathogenic simian-human immunodeficiency virus (SHIV) isolate, SIV89.6PD, by intravenous injection. All of the SIV239Δnef-immunized animals became infected with the SHIV isolate; two of five animals eventually controlled the challenge and three of five animals, which failed to check the immunizing virus, progressed to disease state before the unvaccinated controls. One of five animals immunized with SIVPBj6.6Δnef totally resisted infection by the challenge virus, while three others limited its growth and the remaining animal became persistently infected and eventually died of a pulmonary thrombus. These data indicate that vaccination with attenuated SIV can protect macaques from disease and in some cases from infection by a divergent SHIV. However, if animals are unable to control the immunizing virus, potential damage that can accelerate the disease course of a pathogenic challenge virus may occur. 相似文献
993.
Vieira AR Avila JR Daack-Hirsch S Dragan E Félix TM Rahimov F Harrington J Schultz RR Watanabe Y Johnson M Fang J O'Brien SE Orioli IM Castilla EE Fitzpatrick DR Jiang R Marazita ML Murray JC 《PLoS genetics》2005,1(6):e64
Nonsyndromic or isolated cleft lip with or without cleft palate (CL/P) occurs in wide geographic distribution with an average birth prevalence of 1/700. We used direct sequencing as an approach to study candidate genes for CL/P. We report here the results of sequencing on 20 candidate genes for clefts in 184 cases with CL/P selected with an emphasis on severity and positive family history. Genes were selected based on expression patterns, animal models, and/or role in known human clefting syndromes. For seven genes with identified coding mutations that are potentially etiologic, we performed linkage disequilibrium studies as well in 501 family triads (affected child/mother/father). The recently reported MSX1 P147Q mutation was also studied in an additional 1,098 cleft cases. Selected missense mutations were screened in 1,064 controls from unrelated individuals on the Centre d'Étude du Polymorphisme Humain (CEPH) diversity cell line panel. Our aggregate data suggest that point mutations in these candidate genes are likely to contribute to 6% of isolated clefts, particularly those with more severe phenotypes (bilateral cleft of the lip with cleft palate). Additional cases, possibly due to microdeletions or isodisomy, were also detected and may contribute to clefts as well. Sequence analysis alone suggests that point mutations in FOXE1, GLI2, JAG2, LHX8, MSX1, MSX2, SATB2, SKI, SPRY2, and TBX10 may be rare causes of isolated cleft lip with or without cleft palate, and the linkage disequilibrium data support a larger, as yet unspecified, role for variants in or near MSX2, JAG2, and SKI. This study also illustrates the need to test large numbers of controls to distinguish rare polymorphic variants and prioritize functional studies for rare point mutations. 相似文献
994.
应用均匀设计、二次多项式逐步回归分析对烟管菌(Bjerkandera adusta)WZFF.W-Y11产漆酶液态发酵培养基进行优化。结果表明,培养基组成为麸皮水解液1%、淀粉24.0 g/L、葡萄糖24.0 g/L、豆饼粉4.8 g/L、NH4Cl 3.2g/L、KH2PO4 3.2 g/L、MgSO4·7H2O 0.2 g/L、CuSO4 ·5H2O 0.006 g/L,起始pH6.5,在28℃、150r/min、250mL的摇瓶培养条件下可以稳定地获得9672U/L的漆酶活力。 相似文献
995.
Cinnamate 4-hydroxylase (C4H), a monooxygenase in the plant phenylpropanoid pathway, was assayed for its ability to hydroxylate 29 substrate analogues. Nine of the tested analogues with various aromatic side chains, including 3-coumaric acid, were metabolized by C4H. Seven products from these reactive analogues were characterized using LC/MS, 1H NMR and 13C NMR spectroscopic analysis. For example, caffeic acid was the product of 3-coumaric acid. The products 4-hydroxy-2-chlorocinnamic acid and 4-hydroxy-2-ethoxycinnamic acid are novel compounds that have not been previously reported. The kinetic parameters of C4H towards these analogues were determined. 相似文献
996.
Jiang Q Huang J Li WQ Cavinato T Keller JR Durum SK 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(1):228-234
Signals from the IL-7R are uniquely required for T cell development and maintenance, despite the resemblance of IL-7R to other cytokine receptors and the apparent sharing of common signaling pathways. This unique requirement could either reflect unique expression of IL-7R or IL-7, or it could indicate that the IL-7R delivers unique signals. To determine whether the IL-7R provided unique signals, we exchanged its intracellular domain with that of other cytokine receptors: IL-4R, IL-9R, and prolactin receptor (PRLR). Chimeric receptors were used to reconstitute development of IL-7R(-/-) hemopoietic progenitors by transducing the receptors in retroviral vectors. Whereas IL-7R(-/-) thymocytes are arrested at the double-negative stage, IL-4R, IL-9R, or PRLR all imparted some progression to the double-positive stage. IL-4R and PRLR gave only small numbers of thymocytes, whereas IL-9R gave robust alphabeta T cell development and reconstitution of peripheral CD4 and CD8 cells, indicating that it can duplicate many of the functions of IL-7R. However, IL-9R failed to reconstitute rearrangement of the TCRgamma locus or development of gammadelta T cells. Thus, the IL-7R signals required in the alphabeta T cell lineage (such as survival and proliferation) are not unique to this receptor, whereas rearrangement of the TCRgamma locus may require a signal that is not shared by other receptors. 相似文献
997.
998.
Phenyllactic acid (PLA) is a novel antimicrobial compound derived from phenylalanine (Phe). Lactobacillus sp. SK007, having high PLA-producing ability, was isolated from Chinese traditional pickles. When 6.1 mM phenylpyruvic acid
(PPA) was used to replace Phe as substrate at the same concentration, PLA production increased 14-fold and the fermentation
time decreased from 72 h to 24 h with growing cells. With resting cells, however, 6.8 mM PLA could be obtained as optimal
yield using the following conditions: 12 mM PPA, 55 mM glucose, pH 7.5, 35°C and 4 h. 相似文献
999.
1000.
Peroxisome proliferator activated receptor-gamma (PPAR-gamma) mediates the action of gamma linolenic acid in breast cancer cells 总被引:6,自引:0,他引:6
Jiang WG Redfern A Bryce RP Mansel RE 《Prostaglandins, leukotrienes, and essential fatty acids》2000,62(2):119-127
Gamma linolenic acid (GLA) is a polyunsaturated fatty acid, which induces cytotoxicity and regulates cell adhesion in cancer cells. The molecular mechanism of these actions is not clear. We have shown that GLA acts via peroxisome proliferator activated receptors (PPARs), by stimulating their phosphorylation and translocation to the nucleus. Removing PPAR gamma with antisense oligos abolished the effect of GLA on the expression of adhesion molecules and tumour suppressor genes, whereas removal of PPAR alpha had no effect. Tissues from patients with breast cancer showed a reduction of expression of both PPARs in cancer tissues, as compared with normal. Thus, PPAR gamma serves as the receptor for GLA in the regulation of gene expression in breast cancer cells. 相似文献