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11.
BACKGROUND: Cleft lip (CL) with or without palate (CLP) and isolated cleft palate (CP) are etiologically complex diseases with interactions among various environmental and genetic factors. The aim of the current study was to identify association with genetic markers and phenotypic craniofacial data in patients with CL/CLP/CP parents. METHODS: Posteroanterior and lateral digital radiographs of the cranium were obtained from 74 parents of patients with CL/CLP/CP. One hundred seventy‐three patients with CL/CLP/CP and 190 controls were enrolled in the study for the association test. Five genetic markers of the IRF6 gene and 14 markers of the 19q13 locus were genotyped. Linear regression analysis was performed for the relationship of cephalometric measurements with genotype data adjusted for age, gender, and cleft type. Chi‐square and transmission disequilibrium tests were performed to evaluate differences in alleles of the BCL3 gene. Positive findings were replicated in an independent sample (n = 95) of patients with CL/CLP/CP parents. RESULTS: Genetic markers of the BCL3 gene at 19q13, rs7257231, and rs1979377 in the familial association test and rs10401176 in the case‐control association test, were associated with craniofacial phenotype. Carriers of BCL3 allele rs7257231T had longer posterior cranial bases than noncarriers (padjusted = 0.0028), and in the familial‐based association test showed the statistically strongest relationship (padjusted = 0.05) to phenotype. Relation of rs7257231 to facial formation was confirmed in the replication group (p = 0.0024). CONCLUSIONS: The results indicate that BCL3, which has functions related to cell adhesion and whose downregulation can cause disruption of ectodermal development, is likely to be important in facial formation. Birth Defects Research (Part A), 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
12.
Altered glyoxalase‐1 (GLO‐1) activity and expression is associated with the development of late diabetic complications, malignancy and oxidative stress‐ and aging‐related diseases. In the present study, we developed a flow cytometry method for GLO‐1 detection in human leukocytes isolated from peripheral blood samples to investigate GLO‐1 expression in leukocyte subsets from type 1 and 2 diabetes mellitus patients (n = 11) and healthy subjects (n = 8). The flow cytometry analysis of GLO‐1 in leukocytes showed that expression index of GLO‐1‐positive cells was slightly increased in mononuclear leukocytes from diabetic patients. This result correlated with the increase in GLO‐1 activity in the whole blood samples of type 2 diabetes patients. In conclusion, the present study demonstrates that flow cytometry is suitable for the detection of the GLO‐1 enzyme in human leukocytes and that this method could be used to investigate the fast adaptation of the glyoxalase system related to the pathogenesis of late complications of diabetes mellitus and other glycation stress‐related disorders. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
13.
Whereas hepatocytes secrete the major human plasma high density lipoproteins (HDL)-protein, apo A-I, as lipid-free and lipidated species, the biogenic itineraries of apo A-II and apo E are unknown. Human plasma and HepG2 cell-derived apo A-II and apo E occur as monomers, homodimers and heterodimers. Dimerization of apo A-II, which is more lipophilic than apo A-I, is catalyzed by lipid surfaces. Thus, we hypothesized that lipidation of intracellular and secreted apo A-II exceeds that of apo A-I, and once lipidated, apo A-II dimerizes. Fractionation of HepG2 cell lysate and media by size exclusion chromatography showed that intracellular apo A-II and apo E are fully lipidated and occur on nascent HDL and VLDL respectively, while only 45% of intracellular apo A-I is lipidated. Secreted apo A-II and apo E occur on small HDL and on LDL and large HDL respectively. HDL particles containing both apo A-II and apo A-I form only after secretion from both HepG2 and Huh7 hepatoma cells. Apo A-II dimerizes intracellularly while intracellular apo E is monomeric but after secretion associates with HDL and subsequently dimerizes. Thus, HDL apolipoproteins A-I, A-II and E have distinct intracellular and post-secretory pathways of hepatic lipidation and dimerization in the process of HDL formation. These early forms of HDL are expected to follow different apolipoprotein-specific pathways through plasma remodeling and reverse cholesterol transport.  相似文献   
14.
We reported previously that the incorporation of sugars intoglycosphingolipids (GSL) is diminished in SW13 cells that lacka vimentin intermediate filament (IF) network (vim–) comparedto vim+ cells. To further analyze the nature of this abnormality,we double-labeled cells with 3H-serine and l4C-sugars. Therewas no difference between vim+ and vim– cells in the incorporationof serine into GSL, although the usual difference in sugar incorporationwas observed. This indicated that the defect in vim– cellswas not in the incorporation of sugars into ceramide synthesizedde novo by acylation of sphinganine (pathway 1). Sugars canalso be incorporated into ceramide synthesized from sphingosinethat is derived from catabolism of sphin-golipids (pathway 2),and into GSL that recycle through the Golgi apparatus from endosomes(pathway 3). The amount of galactose and glucosamine incorporatedinto GSL in these three pathways was analyzed by the use oftwo inhibitors of sphingolipid biosynthesis. ß-Chloroala-nineinhibits the de novo synthesis of sphinganine (pathway 1), andfumonisin Bl inhibits the acylation of sphinganine and sphingosine(pathways 1 and 2). We were surprised to observe that in bothvim+ and vim– cells only 20–40% of sugar incorporationinto GSL took place in pathway 1, and 60–80% of sugarincorporation took place in the recycling pathways. Moreover,in contrast to larger GSL, GlcCer was not synthesized in pathway3. Our observations indicate that vimentin IF facilitate therecycling of GSL and sphingosine, and that the differences betweenvim+ and vim– cells are predominantly in pathways 2 and3. Furthermore, although it is generally believed that virtuallyall GSL are synthesized in the de novo pathway, these data indicatethat the recyling pathways predominate in the incorporationof sugars into GSL in SW13 cells. glycosphingolipid biosynthesis intermediate filaments SW13 cells sphingolipid recycling vimentin  相似文献   
15.
The mitochondrial fraction of diethylstilbestrol-treated rat uteri, known to contain an estrogen-induced peroxidase, was able to catalyze the release of 3H2O from either [2-3H]- or [4-3H]estradiol. Hydrogen peroxide added to this system increased the yield of 3H2O but had no effect on mitochondrial preparations from ovariectomized rat uteri having only very low peroxidase activity. The reaction was inhibited by catalase and also occurred with lactoperoxidase in the presence of H2O2 but 2-hydroxyestradiol was not detected in any of these experiments. Under similar conditions, tyrosinase catalyzed the formation of the catechol estrogen with loss of 3H from [2-3H]- or [2,4,6,7-3H]- but not [4-3H]- or [6,7-3H]estradiol. It is proposed that the formation of 3H2O from 3H-labeled estradiol in the estrogen-treated rat uterus may occur by a peroxidative mechanism which does not necessarily result in hydroxylation of the steroid.  相似文献   
16.
Electron Microscopy of Herpes Simplex Virus: I. Entry   总被引:45,自引:31,他引:14  
Although capsids of herpes simplex virus were encountered within phagocytic vesicles, they were more commonly observed free within the cytoplasm. Stages in the release of virus from vesicles were not seen. There appeared to be five distinct steps in the process whereby the virus initiates infection: attachment, digestion of the viral envelope, digestion of the cell wall, passage of the capsid directly into the cytoplasm, and digestion of the capsid with release of the core. Antibody probably interferes with the first two stages.  相似文献   
17.
A strategy allowing both stereocontrol and control over structural isomer formation has been defined for the antimalarial flindersial alkaloids. The recently reported flinderoles were demonstrated to be derived from the natural product borrerine. The structural isomers of flinderoles, the borreverines, were also produced in vitro along with the flinderoles through the dimerization of borrerine in acidic conditions. This result is thought to replicate the biosynthesis of these compounds. Flinderoles A, B, and C, desmethylflinderole C, isoborreverine, and dimethylisoborreverine can each be synthesized in three steps from tryptamine. Furthermore, progress toward a concise enantioselective synthesis of flinderoles A, B, and C is described. This work includes enantioselective conjugate addition to an unprotected indole‐appended enone. Chirality 27:14–17, 2015. © 2013 Wiley Periodicals, Inc.  相似文献   
18.
Small, dense, electronegative low density lipoprotein [LDL(-)] is increased in patients with familial hypercholesterolemia and diabetes, populations at increased risk for coronary artery disease. It is present to a lesser extent in normolipidemic subjects. The mechanistic link between small, dense LDL(-) and atherogenesis is not known. To begin to address this, we studied the composition and dynamics of small, dense LDL(-) from normolipidemic subjects. NEFA levels, which correlate with triglyceride content, are quantitatively linked to LDL electronegativity. Oxidized LDL is not specific to small, dense LDL(-) or lipoprotein [a] (i.e., abnormal lipoprotein). Apolipoprotein C-III is excluded from the most abundant LDL (i.e., that of intermediate density: 1.034 < d < 1.050 g/ml) but associated with both small and large LDL(-). In contrast, lipoprotein-associated phospholipase A(2) (LpPLA(2)) is highly enriched only in small, dense LDL(-). The association of LpPLA(2) with LDL may occur through amphipathic helical domains that are displaced from the LDL surface by contraction of the neutral lipid core.  相似文献   
19.
Thaumatin-like proteins (TLPs) are pathogenesis-related proteins, which are involved in plant defense responses to pathogen infection. Expression of the Pinus sylvestris L. TLP gene is up-regulated by methyl jasmonate treatment and inoculation with Heterobasidion annosum. A full-length Pinus taeda TLP gene sequence was used to design PCR primers for amplification of the full-length TLP gene from P. sylvestris. A putative 705-bp open reading frame of TLP gene was cloned into Escherichia coli cells, and then subcloned into the overexpression vector pET100 using BL21 Star expression bacteria. Optimization of the expression of recombinant TLP was achieved by decreasing both expression temperature and IPTG concentration. The purified 24.6-kDa TLP shows antimicrobial activity against 12 fungal species.  相似文献   
20.
Early forms of high-density lipoproteins (HDL), nascent HDL, are formed by the interaction of apolipoprotein AI with macrophage and hepatic ATP-binding cassette transporter member 1. Various plasma activities convert nascent to mature HDL, comprising phosphatidylcholine (PC) and cholesterol, which are selectively removed by hepatic receptors. This process is important in reducing the cholesterol burden of arterial wall macrophages, an important cell type in all stages of atherosclerosis. Interaction of apolipoprotein AI with dimyristoyl (DM)PC forms reconstituted (r)HDL, which is a good model of nascent HDL. rHDL have been used as an antiathersclerosis therapy that enhances reverse cholesterol transport in humans and animal models. Thus, identification of the structure of rHDL would inform about that of nascent HDL and how rHDL improves reverse cholesterol transport in an atheroprotective way. Early studies of rHDL suggested a discoidal structure, which included pairs of antiparallel helices of apolipoprotein AI circumscribing a phospholipid bilayer. Another rHDL model based on small angle neutron scattering supported a double superhelical structure. Herein, we report a cryo-electron microscopy-based model of a large rHDL formed spontaneously from apolipoprotein AI, cholesterol, and excess DMPC and isolated to near homogeneity. After reconstruction we obtained an rHDL structure comprising DMPC, cholesterol, and apolipoprotein AI (423:74:1 mol/mol) forming a discoidal particle 360 Å in diameter and 45 Å thick; these dimensions are consistent with the stoichiometry of the particles. Given that cryo-electron microscopy directly observes projections of individual rHDL particles in different orientations, we can unambiguously state that rHDL particles are protein bounded discoidal bilayers.  相似文献   
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