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991.
992.
SAR around 4,6-diaminopyrimidine derivatives allowed the discovery of the first potent dual M(3) antagonists and PDE4 inhibitors. Various chemical modulations around that scaffold led to the discovery of ucb-101333-3 which is characterized by the most interesting profile on both targets.  相似文献   
993.
Carnitine biosynthesis from lysine and methionine involves five enzymatic reactions. γ-butyrobetaine hydroxylase (BBH; EC 1.14.11.1) is the last enzyme of this pathway. It catalyzes the reaction of hydroxylation of γ-butyrobetaine to carnitine. The cDNA encoding this enzyme has been isolated and characterized. The cDNA contained an open reading frame of 1161 bp encoding a protein of 387 amino acids with a deduced molecular weight of 44.5 kDa. The sequence of the cDNA showed an important homology with the human cDNA recently isolated. Northern analysis showed γ-butyrobetaine hydroxylase expression in the liver and in some extend in the testis and the epididymis. During this study, it also appeared that BBH mRNA expression was undetectable by Northern analysis during the perinatal period. During the development of the rat, the amount of BBH mRNA appeared after the weaning of the young rat and reached a maximal expression at the adult stage.  相似文献   
994.
Starch is subjected to chemical treatments such as cross-linking or hydroxypropylation to meet the material requirements for food uses or controlled release in the pharmaceutical industries. In this work, two types of cross-linking formulations have been employed for the preparation of high amylose starch for use as an excipient for sustained drug release. The structural differences and chain dynamics of the modified starches in the dry and hydrated states have been compared by the use of variable contact time cross polarization-magic angle spinning solid state (13)C NMR spectroscopy.  相似文献   
995.

Objective

The aim of our study was to assess a possible association between plasma inflammatory biomarkers (CRP, IL-6, soluble CD14) and the extent of fibrosis or cirrhosis using a FibroScan® in HIV/HCV co-infected patients.

Methods

This cross-sectional study assessed 60 HIV/HCV co-infected patients who had paired plasma samples and FibroScan® values available. All included patients were controlled for HIV infection (HIV-1 RNA <50 copies/mL) and had detectable HCV RNA levels. Levels of three biomarkers were measured in all samples using commercial ELISA kits. Multivariate logistic regression models identified factors associated with the METAVIR stages of fibrosis (F0–F2 vs. F3–F4).

Results

In univariate logistic regression analyses, in addition to sCD14 (odds ratio [OR] = 3.23, 95% confidence interval [95%CI] = 1.30–7.97, P = 0.01), aspartate aminotransferase (AST), alanine aminotransferase, platelet counts, and CD4 cell counts were associated with the stage of liver fibrosis and, thus, were introduced into the model. However, only AST (OR = 1.06, 95%CI = 1.02–1.10, P = 0.0009) was independently associated with F3–F4 stage liver fibrosis.

Conclusions

In our study of HIV/HCV co-infected patients, sCD14 plasma level, a biomarker of monocyte activation, was not independently associated with the F3–F4 stage of liver fibrosis. We hypothesize that the higher levels of inflammation markers observed in HIV/HCV co-infected patients, compared to HCV mono-infected patients, prevent this association being observed within this population.  相似文献   
996.
Polar cells have been described as pairs of specific follicular cells present at each pole of Drosophila egg chambers. They are required at different stages of oogenesis for egg chamber formation and establishment of both the anteroposterior and planar polarities of the follicular epithelium. We show that definition of polar cell pairs is a progressive process since early stage egg chambers contain a cluster of several polar cell marker-expressing cells at each pole, while as of stage 5, they contain invariantly two pairs of such cells. Using cell lineage analysis, we demonstrate that these pre-polar cell clusters have a polyclonal origin and derive specifically from the polar cell lineage, rather than from that giving rise to follicular cells. In addition, selection of two polar cells from groups of pre-polar cells occurs via an apoptosis-dependent mechanism and is required for correct patterning of the anterior follicular epithelium of vitellogenic egg chambers.  相似文献   
997.
998.
The effects of Bax (full-length, FL, and C-terminal truncated, DeltaC) on respiration rate, membrane potential, MgATPase activity and kinetics of regulation of respiration were studied in isolated rat heart mitochondria and permeabilized cardiomyocytes. The results showed that while both Bax-FL and Bax-DeltaC permeabilized the outer mitochondrial membrane, released cytochrome c and reduced the respiration rate, the latter could be fully restored by exogenous cytochrome c only in the case of Bax-DeltaC, but not in presence of Bax-FL. In addition, Bax-FL but not Bax-DeltaC increased the MgATPase activity, and their effects on the mitochondrial membrane potential were quantitatively different. None of these effects was sensitive to cyclosporin A (CsA).It is concluded that Bax-FL affects both the outer and the inner mitochondrial membranes by: (1) opening large pores in the outer membrane; (2) inhibiting some segments of the respiratory chain in the inner membrane; and (3) uncoupling the inner mitochondrial membrane by increasing proton leak without opening the permeability transition pore (PTP).  相似文献   
999.
Maternal homozygosity for three independent mutant hecate alleles results in embryos with reduced expression of dorsal organizer genes and defects in the formation of dorsoanterior structures. A positional cloning approach identified all hecate mutations as stop codons affecting the same gene, revealing that hecate encodes the Glutamate receptor interacting protein 2a (Grip2a), a protein containing multiple PDZ domains known to interact with membrane-associated factors including components of the Wnt signaling pathway. We find that grip2a mRNA is localized to the vegetal pole of the oocyte and early embryo, and that during egg activation this mRNA shifts to an off-center vegetal position corresponding to the previously proposed teleost cortical rotation. hecate mutants show defects in the alignment and bundling of microtubules at the vegetal cortex, which result in defects in the asymmetric movement of wnt8a mRNA as well as anchoring of the kinesin-associated cargo adaptor Syntabulin. We also find that, although short-range shifts in vegetal signals are affected in hecate mutant embryos, these mutants exhibit normal long-range, animally directed translocation of cortically injected dorsal beads that occurs in lateral regions of the yolk cortex. Furthermore, we show that such animally-directed movement along the lateral cortex is not restricted to a single arc corresponding to the prospective dorsal region, but occur in multiple meridional arcs even in opposite regions of the embryo. Together, our results reveal a role for Grip2a function in the reorganization and bundling of microtubules at the vegetal cortex to mediate a symmetry-breaking short-range shift corresponding to the teleost cortical rotation. The slight asymmetry achieved by this directed process is subsequently amplified by a general cortical animally-directed transport mechanism that is neither dependent on hecate function nor restricted to the prospective dorsal axis.  相似文献   
1000.
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