938 resultados para Recombinant human BMP-7
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A 37-year-old woman was admitted to hospital and over the next 5 days developed a progressive encephalitis. Nuchal skin biopsy, analyzed using a Rabies TaqMan(C) PCR, demonstrated rabies virus RNA. She had a history in keeping with exposure to rabies whilst in South Africa, but had not received pre- or post-exposure prophylaxis. She was treated with a therapeutic coma according to the
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Using an antiserum raised to the C-terminal region of neuropeptide Y (NPY) which does not cross-react with pancreatic polypeptide (PP), immunoreactivity has been detected in two different endocrine tumours of the human pancreas in concentrations permitting isolation and structural analysis. In a clinically-typical gastrinoma, resected from the head of pancreas, the concentration of NPY immunoreactivity was 3.4 nmol/g. Reverse phase HPLC analysis of extracts of this tumour resolved a single immunoreactive peptide coeluting with synthetic human NPY. The molecular mass of the isolated peptide, determined by mass spectroscopy, was 4270 Da, which was in close agreement with that derived from the deduced primary structure of human tumour NPY (4271.7 Da), obtained by gas-phase sequencing. A somatostatinoma, resected from the region of the ampulla of Vater, contained 3.8 nmol/g of NPY immunoreactivity and isolation of this immunoreactive peptide followed by structural analyses, indicated a molecular structure consistent with NPY 3-36. These data suggest that NPY immunoreactivity detected in human pancreatic endocrine tumours is molecularly heterogenous, a finding which may be of relevance in the symptomatology of such tumours as attenuation of the N-terminus of this peptide generates receptor selectivity.
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Abstract Background IL-31 is a novel cytokine that has been implicated in allergic diseases such as atopic dermatitis and more recently asthma. While IL-31 has been well studied in skin conditions such as atopic dermatitis, little is known about the role IL-31 plays in asthma and specifically the differentiation process of the bronchial epithelium, which is central to the pathogenesis of allergic asthma. Methods We examined the effects of IL-13 (20 ng/ml), IL-31 (20 ng/ml) and an IL-13/IL-31 combination stimulation (20 ng/ml each) on the in vitro mucociliary differentiation of paediatric bronchial epithelial cells (PBECs) from healthy patients (n=6). IL-31 receptor (IL-31-RA) expression, markers of differentiation (goblet and ciliated cells), transepithelial electrical resistance (TEER), quantification of goblet and ciliated cells, real time PCR for MUC5AC, ELISA for VEGF, EGF and MCP-1 (CCL-2) and ELISA for MUC5AC were assessed. Results We found that well-differentiated PBECs expressed IL-31-RA however it's expression did not increase upon stimulation with IL-31 or either of the other treatments. TEER indicated good formation of tight junctions which was found to be similar across all treatment groups (p=0.9). We found that IL-13 alone significantly reduced the number of ciliated cells compared with unstimulated (IL-13 stimuation: mean=4.8% (SD=2.5); unstimulated: mean=15.9%, (SD=7.4), p
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In this paper, we present a Statistical Shape Model for Human Figure Segmentation in gait sequences. Point Distribution Models (PDM) generally use Principal Component analysis (PCA) to describe the main directions of variation in the training set. However, PCA assumes a number of restrictions on the data that do not always hold. In this work, we explore the potential of Independent Component Analysis (ICA) as an alternative shape decomposition to the PDM-based Human Figure Segmentation. The shape model obtained enables accurate estimation of human figures despite segmentation errors in the input silhouettes and has really good convergence qualities.
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We have cloned and studied the expression in Escherichia coli K-12 of chromosomal rfb genes determining the biosynthesis of the O7 lipopolysaccharide (LPS) antigen from E. coli K1 strain VW187. Two E. coli K-12 strains carrying recombinant cosmids gave positive coagglutination reactions with protein A-rich staphylococcal particles bearing an O7-specific rabbit polyclonal antiserum. Silver-stained polyacrylamide gels of total membranes extracted with hot phenol showed O side chain material which had O7 specificity as determined by immunoblotting experiments. However, the amount of O7 LPS expressed in E. coli K-12 was considerably lower than that produced by the wild-type strain VW187. Deletion and transposition experiments identified a region of about 17 kilobase pairs which is essential for the expression of O7 LPS. The existence of homologies between the O7 LPS genes and other E. coli O side chain genes was investigated by Southern blot hybridization experiments. An O7-specific probe fragment of 15 kilobase pairs did not hybridize to genomic DNA digests of E. coli strains belonging to several different O types, demonstrating that the O7 LPS genes are unique.
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We have cloned chromosomal genes determining the aerobactin iron transport system from the Escherichia coli K1 strain VW187. Mapping and hybridization experiments showed that the VW187 aerobactin region was identical to that of the plasmid ColV-K30. However, in the E. coli K-12 background, the biosynthesis of both siderophore and ferric aerobactin receptor encoded by the VW187-derived recombinant plasmids was not repressed by iron to the same extent found when a recombinant plasmid derived from pColV-K30 was used. RNA-DNA dot-blot hybridization experiments demonstrated that the aerobactin-specific mRNA synthesized by the VW187-derived clones was not iron regulated in E. coli K-12. In contrast, the synthesis of aerobactin and its receptor in strain VW187 was completely repressed by iron regardless of whether the recombinant plasmids originated from VW187 or pColV-K30. Similar results were obtained with gene fusions in which a promoterless lac operon was placed under the control of aerobactin promoter regions of either chromosome- or plasmid-mediated aerobactin systems. DNA sequencing of the chromosomal aerobactin promoter region showed changes in bases located immediately upstream to the -35 region compared with the corresponding region in pColV-K30, which is known to be part of the binding site for the Fur repressor protein.
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IQGAPs are cytoskeletal scaffolding proteins which collect information from a variety of signalling pathways and pass it on to the microfilaments and microtubules. There is a well-characterised interaction between IQGAP and calmodulin through a series of IQ-motifs towards the middle of the primary sequence. However, it has been shown previously that the calponin homology domain (CHD), located at the N-terminus of the protein, can also interact weakly with calmodulin. Using a recombinant fragment of human IQGAP1 which encompasses the CHD, we have demonstrated that the CHD undergoes a calcium ion-dependent interaction with calmodulin. The CHD can also displace the hydrophobic fluorescent probe 1-anilinonaphthalene-8-sulphonate from calcium-calmodulin, suggesting that the interaction involves non-polar residues on the surface of calmodulin. Molecular modelling identified a possible site on the CHD for calmodulin interaction. The physiological significance of this interaction remains to be discovered.
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Umbilical cord blood-derived endothelial colony-forming cells (UCB-ECFC) show utility in neovascularization, but their contribution to osteogenesis has not been defined. Cocultures of UCB-ECFC with human fetal-mesenchymal stem cells (hfMSC) resulted in earlier induction of alkaline phosphatase (ALP) (Day 7 vs. 10) and increased mineralization (1.9×; p <.001) compared to hfMSC monocultures. This effect was mediated through soluble factors in ECFC-conditioned media, leading to 1.8-2.2× higher ALP levels and a 1.4-1.5× increase in calcium deposition (p <.01) in a dose-dependent manner. Transcriptomic and protein array studies demonstrated high basal levels of osteogenic (BMPs and TGF-ßs) and angiogenic (VEGF and angiopoietins) regulators. Comparison of defined UCB and adult peripheral blood ECFC showed higher osteogenic and angiogenic gene expression in UCB-ECFC. Subcutaneous implantation of UCB-ECFC with hfMSC in immunodeficient mice resulted in the formation of chimeric human vessels, with a 2.2-fold increase in host neovascularization compared to hfMSC-only implants (p = .001). We conclude that this study shows that UCB-ECFC have potential in therapeutic angiogenesis and osteogenic applications in conjunction with MSC. We speculate that UCB-ECFC play an important role in skeletal and vascular development during perinatal development but less so in later life when expression of key osteogenesis and angiogenesis genes in ECFC is lower.
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In reconstructive surgery, skeletal muscle may endure protracted ischemia before reperfusion, which can lead to significant ischemia/reperfusion injury. Ischemic postconditioning induced by brief cycles of reperfusion/reocclusion at the end of ischemia has been shown to salvage skeletal muscle from ischemia/reperfusion injury in several animal models. However, ischemic postconditioning has not been confirmed in human skeletal muscle. Using an established in vitro human skeletal muscle hypoxic conditioning model, we tested our hypothesis that hypoxic postconditioning salvages ex vivo human skeletal muscle from hypoxia/reoxygenation injury and the mechanism involves inhibition of opening of the mitochondrial permeability transition pore (mPTP) and preservation of ATP synthesis. Muscle strips (~0.5×0.5×15mm) from human rectus abdominis muscle biopsies were cultured in Krebs-Henseleit-HEPES buffer, bubbled with 95%N(2)/5%CO(2) (hypoxia) or 95%O(2)/5%CO(2) (reoxygenation). Samples were subjected to 3h hypoxia/2h reoxygenation. Hypoxic postconditioning was induced by one or two cycles of 5min reoxygenation/5min hypoxia after 3h hypoxia. Muscle injury, viability and ATP synthesis after 2h of reoxygenation were assessed by measuring lactate dehydrogenase (LDH) release, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) reduction and ATP content, respectively. Hypoxic postconditioning or treatment with the mPTP-opening inhibitors Cyclosporine A (CsA, 5×10(-6)M) or N-Methyl-4-isoleucine Cyclosporine (NIM811, 5×10(-6)M) 10min before reoxygenation decreased LDH release, increased MTT reduction and increased muscle ATP content (n=7 patients; P
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Congenital Adrenal Hyperplasia (CAH) is a family of autosomal recessive disorders involving impaired synthesis of cortisol from cholesterol by adrenal cortex. The predominant causes of the disorder are mutations in the CYP21A2 gene that encodes a Cytochrome P450 21-hydroxylase enzyme, which is central to steroidogenesis. The severity of the disease depends upon the extent of impaired enzymatic activity and can be classified under severe Classical form or the mild Non-Classical form, Molecular characterisation of CYP21A2 mutations can be used to predict clinical phenotype and disease severity based upon changes it brings in 21-hydroxylase enzyme structure. A humanized model of CYP21A2 has been used to map and investigate the structural role of all known disease-causing mutations. A structural explanation of clinical manifestation allows us to put forward criteria that might allow the prediction of clinical severity of the disease.
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We report the largest market basket survey of arsenic (As) in U.S. rice to date. Our findings show differences in transitional-metal levels between polished and unpolished rice and geographical variation in As and selenium (Se) between rice processed in California and the South Central U.S. The mean and median As grain levels for the South Central U.S. were 0.30 and 0.27 µg As g-1, respectively, for 107 samples. Levels for California were 41% lower than the South Central U.S., with a mean of 0.17 µg As g-1 and a median of 0.16 µg As g-1 for 27 samples. The mean and median Se grain levels for the South Central U.S. were 0.19 µg Se g-1. Californian rice levels were lower, averaging only 0.08 and 0.06 µg Se g-1 for mean and median values, respectively. The difference between the two regions was found to be significant for As and Se (General Linear Model (GLM):? As p < 0.001; Se p < 0.001). No statistically significant differences were observed in As or Se levels between polished and unpolished rice (GLM:? As p = 0.213; Se p = 0.113). No significant differences in grain levels of manganese (Mn), cobalt (Co), copper (Cu), or zinc (Zn) were observed between California and the South Central U.S. Modeling arsenic intake for the U.S. population based on this survey shows that for certain groups (namely Hispanics, Asians, sufferers of Celiac disease, and infants) dietary exposure to inorganic As from elevated levels in rice potentially exceeds the maximum intake of As from drinking water (based on consumption of 1 L of 0.01 mg L-1 In. As) and Californian state exposure limits. Further studies on the transformation of As in soil, grain As bioavailability in the human gastrointestinal tract, and grain elemental speciation trends are critical.
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IFN-ß, IL-27, and IL-10 have been shown to exert a range of similar immunoregulatory effects in murine and human experimental systems, particularly in Th1- and Th17-mediated models of autoimmune inflammatory disease. In this study we sought to translate some of our previous findings in murine systems to human in vitro models and delineate the interdependence of these different cytokines in their immunoregulatory effects. We demonstrate that human IL-27 upregulates IL-10 in T cell-activated PBMC cultures and that IFN-ß drives IL-27 production in activated monocytes. IFN-ß-driven IL-27 is responsible for the upregulation of IL-10, but not IL-17 suppression, by IFN-ß in human PBMCs. Surprisingly, IL-10 is not required for the suppression of IL-17 by either IL-27 or IFN-ß in this model or in de novo differentiating Th17 cells, nor is IL-27 signaling required for the suppression of experimental autoimmune encephalomyelitis (EAE) by IFN-ß in vivo. Furthermore, and even more surprisingly, IL-10 is not required for the suppression of Th17-biased EAE by IL-27, in sharp contrast to Th1-biased EAE. In conclusion, IFN-ß and IL-27 both induce human IL-10, both suppress human Th17 responses, and both suppress murine EAE. However, IL-27 signaling is not required for the therapeutic effect of IFN-ß in EAE. Suppression of Th17-biased EAE by IL-27 is IL-10-independent, in contrast to its mechanism of action in Th1-biased EAE. Taken together, these findings delineate a complex set of interdependent and independent immunoregulatory mechanisms of IFN-ß, IL-27, and IL-10 in human experimental models and in murine Th1- and Th17-driven autoimmunity.
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Essential to the conduct of epidemiologic studies examining aflatoxin exposure and the risk of heptocellular carcinoma, impaired growth, and acute toxicity has been the development of quantitative biomarkers of exposure to aflatoxins, particularly aflatoxin B-1. In this study, identical serum sample sets were analyzed for aflatoxin-albumin adducts by ELISA, high-performance liquid chromatography (HPLC) with fluorescence detection (HPLC-f), and HPLC with isotope dilution mass spectrometry (IDMS). The human samples analyzed were from an acute aflatoxicosis outbreak in Kenya in 2004 (n = 102) and the measured values ranged from 0.018 to 67.0, nondetectable to 13.6, and 0.002 to 17.7 ng/mg albumin for the respective methods. The Deming regression slopes for the HPLC-f and ELISA concentrations as a function of the IDMS concentrations were 0.71 (r(2) = 0.95) and 3.3 (r(2) = 0.96), respectively. When the samples were classified as cases or controls, based on clinical diagnosis, all methods were predictive of outcome (P < 0.01). Further, to evaluate assay precision, duplicate samples were prepared at three levels by dilution of an exposed human sample and were analyzed on three separate days. Excluding one assay value by ELISA and one assay by HPLC-f, the overall relative SD were 8.7%, 10.5%, and 9.4% for IDMS, HPLC-f, and ELISA, respectively. IDMS was the most sensitive technique and HPLC-f was the least sensitive method. Overall, this study shows an excellent correlation between three independent methodologies conducted in different laboratories and supports the validation of these technologies for assessment of human exposure to this environmental toxin and carcinogen.
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Fumonisins are mycotoxins produced by Fusarium spp. and commonly contaminate maize and maize products worldwide. Fumonisins are rodent carcinogens and have been associated with human esophageal cancer. However, the lack of a valid exposure biomarker has hindered both the assessment of human exposure and the evaluation of disease risk. A sensitive liquid chromatography-mass spectrometry method to measure urinary fumonisin B1 (FB1) following extraction on Oasis MAX cartridges was established and applied to urine samples from women in a cohort recruited in Morelos County, Mexico. Urinary FB1 was compared with dietary information on tortilla consumption. FB1 recovery in spiked samples averaged 94% as judged by deuterium-labeled FB1 internal standard. Urinary FB1 was determined in 75 samples from women selected based on low, medium, or high consumption of maize-based tortillas. The geometric mean (95% confidence interval) of urinary FB1 was 35.0 (18.8-65.2), 63.1 (36.8-108.2), and 147.4 (87.6-248.0) pg/mL and the frequency of samples above the detection limit (set at 20 pg FB1/mL urine) was 45%, 80%, and 96% for the low, medium, and high groups, respectively. Women with high intake had a 3-fold higher average FB1 levels compared with the "low intake" group (F = 7.3; P = 0.0015). Urinary FB1 was correlated with maize intake (P-trend = 0.001); the correlation remained significant after adjusting for age, education, and place of residence. This study suggests that measurement of urinary FB1 is sufficiently sensitive for fumonisin exposure assessment in human populations and could be a valuable tool in investigating the associated health effects of exposure.
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Rationale: Histone deacetylase (HDAC)7 is expressed in the early stages of embryonic development and may play a role in endothelial function.
Objective: This study aimed to investigate the role of HDAC7 in endothelial cell (EC) proliferation and growth and the underlying mechanism.
Methods and Results: Overexpression of HDAC7 by adenoviral gene transfer suppressed human umbilical vein endothelial cell (HUVEC) proliferation by preventing nuclear translocation of ß-catenin and downregulation of T-cell factor-1/Id2 (inhibitor of DNA binding 2) and cyclin D1, leading to G1 phase elongation. Further assays with the TOPFLASH reporter and quantitative RT-PCR for other ß-catenin target genes such as Axin2 confirmed that overexpression of HDAC7 decreased ß-catenin activity. Knockdown of HDAC7 by lentiviral short hairpin RNA transfer induced ß-catenin nuclear translocation but downregulated cyclin D1, cyclin E1 and E2F2, causing HUVEC hypertrophy. Immunoprecipitation assay and mass spectrometry analysis revealed that HDAC7 directly binds to ß-catenin and forms a complex with 14-3-3 e, ?, and ? proteins. Vascular endothelial growth factor treatment induced HDAC7 degradation via PLC?-IP3K (phospholipase C?–inositol-1,4,5-trisphosphate kinase) signal pathway and partially rescued HDAC7-mediated suppression of proliferation. Moreover, vascular endothelial growth factor stimulation suppressed the binding of HDAC7 with ß-catenin, disrupting the complex and releasing ß-catenin to translocate into the nucleus.
Conclusions: These findings demonstrate that HDAC7 interacts with ß-catenin keeping ECs in a low proliferation stage and provides a novel insight into the mechanism of HDAC7-mediated signal pathways leading to endothelial growth