Phenotypic correction of von Willebrand disease type 3 blood-derived endothelial cells with lentiviral vectors expressing von Willebrand factor

Science.gov (United States)

De Meyer, Simon F.; Vanhoorelbeke, Karen; Chuah, Marinee K.; Pareyn, Inge; Gillijns, Veerle; Hebbel, Robert P.; Collen, Désiré; Deckmyn, Hans; VandenDriessche, Thierry

2006-01-01

Von Willebrand disease (VWD) is an inherited bleeding disorder, caused by quantitative (type 1 and 3) or qualitative (type 2) defects in von Willebrand factor (VWF). Gene therapy is an appealing strategy for treatment of VWD because it is caused by a single gene defect and because VWF is secreted into the circulation, obviating the need for targeting specific organs or tissues. However, development of gene therapy for VWD has been hampered by the considerable length of the VWF cDNA (8.4 kb [kilobase]) and the inherent complexity of the VWF protein that requires extensive posttranslational processing. In this study, a gene-based approach for VWD was developed using lentiviral transduction of blood-outgrowth endothelial cells (BOECs) to express functional VWF. A lentiviral vector encoding complete human VWF was used to transduce BOECs isolated from type 3 VWD dogs resulting in high-transduction efficiencies (95.6% ± 2.2%). Transduced VWD BOECs efficiently expressed functional vector-encoded VWF (4.6 ± 0.4 U/24 hour per 106 cells), with normal binding to GPIbα and collagen and synthesis of a broad range of multimers resulting in phenotypic correction of these cells. These results indicate for the first time that gene therapy of type 3 VWD is feasible and that BOECs are attractive target cells for this purpose. PMID:16478886

Association of Single Nucleotide Polymorphisms in the ST3GAL4 Gene with VWF Antigen and Factor VIII Activity.

Science.gov (United States)

Song, Jaewoo; Xue, Cheng; Preisser, John S; Cramer, Drake W; Houck, Katie L; Liu, Guo; Folsom, Aaron R; Couper, David; Yu, Fuli; Dong, Jing-Fei

2016-01-01

VWF is extensively glycosylated with biantennary core fucosylated glycans. Most N-linked and O-linked glycans on VWF are sialylated. FVIII is also glycosylated, with a glycan structure similar to that of VWF. ST3GAL sialyltransferases catalyze the transfer of sialic acids in the α2,3 linkage to termini of N- and O-glycans. This sialic acid modification is critical for VWF synthesis and activity. We analyzed genetic and phenotypic data from the Atherosclerosis Risk in Communities (ARIC) study for the association of single nucleotide polymorphisms (SNPs) in the ST3GAL4 gene with plasma VWF levels and FVIII activity in 12,117 subjects. We also analyzed ST3GAL4 SNPs found in 2,535 subjects of 26 ethnicities from the 1000 Genomes (1000G) project for ethnic diversity, SNP imputation, and ST3GAL4 haplotypes. We identified 14 and 1,714 ST3GAL4 variants in the ARIC GWAS and 1000G databases respectively, with 46% being ethnically diverse in their allele frequencies. Among the 14 ST3GAL4 SNPs found in ARIC GWAS, the intronic rs2186717, rs7928391, and rs11220465 were associated with VWF levels and with FVIII activity after adjustment for age, BMI, hypertension, diabetes, ever-smoking status, and ABO. This study illustrates the power of next-generation sequencing in the discovery of new genetic variants and a significant ethnic diversity in the ST3GAL4 gene. We discuss potential mechanisms through which these intronic SNPs regulate ST3GAL4 biosynthesis and the activity that affects VWF and FVIII.

Association of Single Nucleotide Polymorphisms in the ST3GAL4 Gene with VWF Antigen and Factor VIII Activity.

Directory of Open Access Journals (Sweden)

Jaewoo Song

Full Text Available VWF is extensively glycosylated with biantennary core fucosylated glycans. Most N-linked and O-linked glycans on VWF are sialylated. FVIII is also glycosylated, with a glycan structure similar to that of VWF. ST3GAL sialyltransferases catalyze the transfer of sialic acids in the α2,3 linkage to termini of N- and O-glycans. This sialic acid modification is critical for VWF synthesis and activity. We analyzed genetic and phenotypic data from the Atherosclerosis Risk in Communities (ARIC study for the association of single nucleotide polymorphisms (SNPs in the ST3GAL4 gene with plasma VWF levels and FVIII activity in 12,117 subjects. We also analyzed ST3GAL4 SNPs found in 2,535 subjects of 26 ethnicities from the 1000 Genomes (1000G project for ethnic diversity, SNP imputation, and ST3GAL4 haplotypes. We identified 14 and 1,714 ST3GAL4 variants in the ARIC GWAS and 1000G databases respectively, with 46% being ethnically diverse in their allele frequencies. Among the 14 ST3GAL4 SNPs found in ARIC GWAS, the intronic rs2186717, rs7928391, and rs11220465 were associated with VWF levels and with FVIII activity after adjustment for age, BMI, hypertension, diabetes, ever-smoking status, and ABO. This study illustrates the power of next-generation sequencing in the discovery of new genetic variants and a significant ethnic diversity in the ST3GAL4 gene. We discuss potential mechanisms through which these intronic SNPs regulate ST3GAL4 biosynthesis and the activity that affects VWF and FVIII.

Effects of Endovascular Interventions on vWF and Fb Levels in Type 2 Diabetic Patients with Peripheral Artery Disease.

Science.gov (United States)

Yao, Hua-Qiang; Wang, Fu-Jun; Kang, Zhen

2016-05-01

von Willebrand Factor (vWF) and fibrinogen (Fb) are associated with hypercoagulability and thrombosis, which are the pathology and symptom of arterial disease. This research aims to study the effects of endovascular interventions on blood vWF and Fb levels in patients with diabetic peripheral artery disease (PAD). Totally, 66 type 2 diabetic patients with PAD (intervention group) and 26 type 2 diabetic patients without PAD (control group) were enrolled. These patients are matched at gender, age, and diabetes duration. For PAD patients, percutaneous interventions (balloon dilation or stent implantation) were performed, and blood samples were collected before, during, and after interventions. Then, enzyme-linked immunosorbent assay and prothrombin time-derived method were used to detect the levels of vWF and Fb, respectively. For intervention group, vWF and Fb levels in distal ischemic regions (vWF: 231.3%, Fb: 4.97 g/L) were significantly higher than that in nonischemic regions (vWF: 147.6%, Fb: 3.91 g/L, P value Fb levels were significantly increased (vWF: 299.2%, Fb: 5.69 g/L, P value Fb levels reached a peak (vWF: 199.3%, Fb: 4.96 g/L) and then decreased gradually to lower than the preinterventional levels (vWF: 148.3%, Fb: 3.88 g/L, P value Fb in the first week postintervention, leading to endothelial dysfunction and blood hypercoagulability. It suggested endothelial function protection and anticoagulant therapies should be applied to diabetic PAD patients after interventions. Copyright © 2016 Elsevier Inc. All rights reserved.

VWF mutations and new sequence variations identified in healthy controls are more frequent in the African-American population.

Science.gov (United States)

Bellissimo, Daniel B; Christopherson, Pamela A; Flood, Veronica H; Gill, Joan Cox; Friedman, Kenneth D; Haberichter, Sandra L; Shapiro, Amy D; Abshire, Thomas C; Leissinger, Cindy; Hoots, W Keith; Lusher, Jeanne M; Ragni, Margaret V; Montgomery, Robert R

2012-03-01

Diagnosis and classification of VWD is aided by molecular analysis of the VWF gene. Because VWF polymorphisms have not been fully characterized, we performed VWF laboratory testing and gene sequencing of 184 healthy controls with a negative bleeding history. The controls included 66 (35.9%) African Americans (AAs). We identified 21 new sequence variations, 13 (62%) of which occurred exclusively in AAs and 2 (G967D, T2666M) that were found in 10%-15% of the AA samples, suggesting they are polymorphisms. We identified 14 sequence variations reported previously as VWF mutations, the majority of which were type 1 mutations. These controls had VWF Ag levels within the normal range, suggesting that these sequence variations might not always reduce plasma VWF levels. Eleven mutations were found in AAs, and the frequency of M740I, H817Q, and R2185Q was 15%-18%. Ten AA controls had the 2N mutation H817Q; 1 was homozygous. The average factor VIII level in this group was 99 IU/dL, suggesting that this variation may confer little or no clinical symptoms. This study emphasizes the importance of sequencing healthy controls to understand ethnic-specific sequence variations so that asymptomatic sequence variations are not misidentified as mutations in other ethnic or racial groups.

Dogs with hearth diseases causing turbulent high-velocity blood flow have changes in patelet function and von Willebrand factor multimer distribution

DEFF Research Database (Denmark)

Tarnow, Inge; Kristensen, Annemarie Thuri; Olsen, Lisbeth Høier

2005-01-01

The purpose of this prospective study was to investigate platelet function using in vitro tests based on both high and low shear rates and von Willebrand factor (vWf) multimeric composition in dogs with cardiac disease and turbulent high-velocity blood flow. Client-owned asymptomatic, untreated d...

Soluble multimer of recombinant endostatin expressed in E. coli has anti-angiogenesis activity

International Nuclear Information System (INIS)

Wei Dongmei; Gao Yan; Cao Xiangrong; Zhu Nianchun; Liang Jianfu; Xie Weiping; Zhen Mingying; Zhu Minsheng

2006-01-01

The bioactivity, refolding, and multimer formation of endostatin, particularly of recombinant endostatin produced from bacteria, are proved challenging for clinical application. In order to determine the biological activity of recombinant endostatin multimer, first, we expressed endostatin in Escherichia coli and purified it with ion-exchange chromatography. The purified active protein could elicit multimer formation spontaneously, but still has comparable activity. Aim to determine the anti-angiogenic activity of multimer endostatin, by use of RP-HPLC, we then successfully separated endostatin monomer and multimer for subjecting to anti-angiogenesis assay. The results from CAM (chorioallantoic membrane) inhibition assay showed that both monomer and multimer suppressed CAM vascularization significantly. At the dosage of 0.8 μg, inhibition rates of multimeric and monomeric proteins were about 58% and 38%, respectively. Multimeric endostatin exerted a higher activity than monomeric endostatin (p 0.05), although both of them show a high inhibition effect in contrast to control. The results from HUVEC proliferation assay also showed similar effects at dosages of 0.6 and 1.6 μg/ml, multimer exerted a higher activity on inhibition of HUVEC proliferation comparing with monomer (p < 0.05). In conclusion, our results suggest that endostatin multimer has a comparable or higher bioactivity and multimerization will not affect its bioactivity, implying that endostatin activity is insensitive to structure conformation contributed by disulfide bonds

Conceção, desenvolvimento e implementação de projetos multimédia no Laboratório de Artes Visuais e Multimédia

OpenAIRE

Freitas, Nicole Mendes de

2012-01-01

Dissertação de Mestrado em Comunicação e Multimédia Este documento relata o trabalho realizado no estágio curricular ao longo do 2º ano do Mestrado de Comunicação e Multimédia (MCM), no âmbito da unidade curricular Projeto/Dissertação. O estágio decorreu no Laboratório de Artes Visuais e Multimédia (LAVM), da Escola de Ciências e Tecnologia (ECT), da Universidade de Trás-os-Montes e Alto Douro (UTAD). Surgindo como componente conclusiva do Mestrado, o estágio curricular no LAVM permitiu...

A 12.3-kb Duplication Within the VWF Gene in Pigs Affected by Von Willebrand Disease Type 3

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Stefanie Lehner

2018-02-01

Full Text Available Von Willebrand Disease (VWD type 3 is a serious and sometimes fatal hereditary bleeding disorder. In pigs, the disease has been known for decades, and affected animals are used as models for the human disease. Due to the recessive mode of inheritance of VWD type 3, severe bleeding is typically seen in homozygous individuals. We sequenced the complete porcine VWF (Von Willebrand Factor complementary DNA (cDNA and detected a tandem duplication of exons 17 and 18, causing a frameshift and a premature termination codon (p.Val814LeufsTer3 in the affected pig. Subsequent next generation sequencing on genomic DNA proved the existence of a 12.3-kb tandem duplication associated with VWD. This duplication putatively originates from porcine Short Interspersed Nuclear Elements (SINEs located within VWF introns 16 and 18 with high identity. The premature termination truncates the VWF open reading frame by a large part, resulting in an almost entire loss of the mature peptide. It is therefore supposed to account for the severe VWD type 3. Our results further indicate the presence of strong, nonsense-mediated decay in VWF messenger RNA (mRNA containing the duplication, which was supported by the almost complete absence of the complete VWF protein in immunohistochemistry analysis of the VWD-affected pig. In the past, differentiation of wild-type and heterozygous pigs in this VWD colony had to rely on clinical examinations and additional laboratory methods. The present study provides the basis to distinguish both genotypes by performing a rapid and simple genetic analysis.

Probing ADAMTS13 substrate specificity using phage display.

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Karl C Desch

Full Text Available Von Willebrand factor (VWF is a large, multimeric protein that regulates hemostasis by tethering platelets to the subendothelial matrix at sites of vascular damage. The procoagulant activity of plasma VWF correlates with the length of VWF multimers, which is proteolytically controlled by the metalloprotease ADAMTS13. To probe ADAMTS13 substrate specificity, we created phage display libraries containing randomly mutated residues of a minimal ADAMTS13 substrate fragment of VWF, termed VWF73. The libraries were screened for phage particles displaying VWF73 mutant peptides that were resistant to proteolysis by ADAMTS13. These peptides exhibited the greatest mutation frequency near the ADAMTS13 scissile residues. Kinetic assays using mutant and wild-type substrates demonstrated excellent agreement between rates of cleavage for mutant phage particles and the corresponding mutant peptides. Cleavage resistance of selected mutations was tested in vivo using hydrodynamic injection of corresponding full-length expression plasmids into VWF-deficient mice. These studies confirmed the resistance to cleavage resulting from select amino acid substitutions and uncovered evidence of alternate cleavage sites and recognition by other proteases in the circulation of ADAMTS13 deficient mice. Taken together, these studies demonstrate the key role of specific amino acids residues including P3-P2' and P11', for substrate specificity and emphasize the importance in flowing blood of other ADAMTS13-VWF exosite interactions outside of VWF73.

Relationship between ADAMTS13 activity, von Willebrand factor antigen levels and platelet function in the early and late phases after TIA or ischaemic stroke.

Science.gov (United States)

McCabe, Dominick J H; Murphy, Stephen J X; Starke, Richard; Harrison, Paul; Brown, Martin M; Sidhu, Paul S; Mackie, Ian J; Scully, Marie; Machin, Samuel J

2015-01-15

Reduced ADAMTS13 activity is seen in thrombotic thrombocytopenic purpura (TTP), and may lead to accumulation of prothrombotic ultra-large von Willebrand factor (ULVWF) multimers in vivo. ADAMTS13 activity and its relationship with VWF antigen (VWF:Ag) levels and platelet function in 'non-TTP related' TIA or ischaemic stroke has not been comprehensively studied. In this prospective pilot observational analytical case-control study, ADAMTS13 activity and VWF:Ag levels were quantified in platelet poor plasma in 53 patients in the early phase (≤ 4 weeks) and 34 of these patients in the late phase (≥ 3 months) after TIA or ischaemic stroke on aspirin. Data were compared with those from 22 controls not on aspirin. The impact of ADAMTS13 on platelet function in whole blood was quantified by measuring Collagen-ADP (C-ADP) and Collagen-Epinephrine closure times on a platelet function analyser (PFA-100(®)). Median ADAMTS13 activity was significantly reduced in the early phase (71.96% vs. 95.5%, P TIA or stroke compared with controls (86.3% vs. 95.5%, P=0.19). There was a significant inverse relationship between ADAMTS13 activity and VWF:Ag levels in the early phase (r=-0.31; P=0.024), but not in the late phase after TIA or stroke (P=0.74). There was a positive correlation between ADAMTS13 activity and C-ADP closure times in early phase patients only, likely mediated via VWF:Ag levels. ADAMTS13 activity is reduced and VWF:Ag expression is increased within 4 weeks of TIA or ischaemic stroke onset, and can promote enhanced platelet adhesion and aggregation in response to stimulation with collagen and ADP via VWF-mediated pathways. These data improve our understanding of the dynamic haemostatic and thrombotic profiles of ischaemic cerebrovascular disease (CVD) patients, and are important in view of the potential future role that ADAMTS13 may have to play as an anti-thrombotic agent in CVD. Copyright © 2014 Elsevier B.V. All rights reserved.

Technological advances in diagnostic testing for von Willebrand disease: new approaches and challenges.

Science.gov (United States)

Hayward, C P M; Moffat, K A; Graf, L

2014-06-01

Diagnostic tests for von Willebrand disease (VWD) are important for the assessment of VWD, which is a commonly encountered bleeding disorder worldwide. Technical innovations have been applied to improve the precision and lower limit of detection of von Willebrand factor (VWF) assays, including the ristocetin cofactor activity assay (VWF:RCo) that uses the antibiotic ristocetin to induce plasma VWF binding to glycoprotein (GP) IbIXV on target platelets. VWF-collagen-binding assays, depending on the type of collagen used, can improve the detection of forms of VWD with high molecular weight VWF multimer loss, although the best method is debatable. A number of innovations have been applied to VWF:RCo (which is commonly performed on an aggregometer), including replacing the target platelets with immobilized GPIbα, and quantification by an enzyme-linked immunosorbent assay (ELISA), immunoturbidimetric, or chemiluminescent end-point. Some common polymorphisms in the VWF gene that do not cause bleeding are associated with falsely low VWF activity by ristocetin-dependent methods. To overcome the need for ristocetin, some new VWF activity assays use gain-of-function GPIbα mutants that bind VWF without the need for ristocetin, with an improved precision and lower limit of detection than measuring VWF:RCo by aggregometry. ELISA of VWF binding to mutated GPIbα shows promise as a method to identify gain-of-function defects from type 2B VWD. The performance characteristics of many new VWF activity assays suggest that the detection of VWD, and monitoring of VWD therapy, by clinical laboratories could be improved through adopting newer generation VWF assays. © 2014 John Wiley & Sons Ltd.

Probing ADAMTS13 Substrate Specificity using Phage Display

Science.gov (United States)

Desch, Karl C.; Kretz, Colin; Yee, Andrew; Gildersleeve, Robert; Metzger, Kristin; Agrawal, Nidhi; Cheng, Jane; Ginsburg, David

2015-01-01

Von Willebrand factor (VWF) is a large, multimeric protein that regulates hemostasis by tethering platelets to the subendothelial matrix at sites of vascular damage. The procoagulant activity of plasma VWF correlates with the length of VWF multimers, which is proteolytically controlled by the metalloprotease ADAMTS13. To probe ADAMTS13 substrate specificity, we created phage display libraries containing randomly mutated residues of a minimal ADAMTS13 substrate fragment of VWF, termed VWF73. The libraries were screened for phage particles displaying VWF73 mutant peptides that were resistant to proteolysis by ADAMTS13. These peptides exhibited the greatest mutation frequency near the ADAMTS13 scissile residues. Kinetic assays using mutant and wild-type substrates demonstrated excellent agreement between rates of cleavage for mutant phage particles and the corresponding mutant peptides. Cleavage resistance of selected mutations was tested in vivo using hydrodynamic injection of corresponding full-length expression plasmids into VWF-deficient mice. These studies confirmed the resistance to cleavage resulting from select amino acid substitutions and uncovered evidence of alternate cleavage sites and recognition by other proteases in the circulation of ADAMTS13 deficient mice. Taken together, these studies demonstrate the key role of specific amino acids residues including P3-P2’ and P11’, for substrate specificity and emphasize the importance in flowing blood of other ADAMTS13–VWF exosite interactions outside of VWF73. PMID:25849793

Discontinuation of antithrombotic therapy for a year or more in patients with continuous-flow left ventricular assist devices.

Science.gov (United States)

Pereira, Naveen L; Chen, Dong; Kushwaha, Sudhir S; Park, Soon J

2010-10-01

The recommended anticoagulation regimen during continuous-flow axial left ventricular assist device (LVAD) support is aspirin and warfarin with a targeted international normalized ratio of 2.0-3.0. We report two patients in whom recurrent gastrointestinal bleeding during LVAD support necessitated discontinuation of this anti-thrombotic regimen for a year or more. Despite this, neither patients developed thrombotic complications during 29 patient-months of follow-up. An acquired von Willebrand factor (VWF) abnormality reflected by the absence or decreased abundance of the highest molecular weight multimers was demonstrated in both patients. The gold standard test for platelet function, light transmission platelet aggregometry was measured in one patient and was normal, indicative that the predominant abnormality in the coagulation profile of these patients is an acquired VWF syndrome. Clinical trials are required to address the question whether it is safe to discontinue anticoagulation in LVAD patients with acquired VWF abnormalities.

O turning point da grande reportagem multimídia

OpenAIRE

Longhi, Raquel Ritter; Universidade Federal de Santa Catarina / Campus Reitor João David Ferreira Lima. Florianópolis, Santa Catarina. Brasil. CEP: 88049-900 Tel: (48) 3721.9000

2015-01-01

Este artigo analisa o estado da arte da grande reportagem multimídia no jornalismo online, atentando para um momento que se pode definir como “turning point”, ou ponto de virada desse tipo de formato noticioso. A partir de uma sistematização da evolução dos formatos expressivos multimidiáticos da notícia no jornalismo digital, o artigo identifica três momentos principais dessa trajetória: o slide-show noticioso, no início dos anos 2000; os especiais multimídia, de meados de 2000 a 2011 e a gr...

Next-generation detection of antigen-responsive T cells using DNA barcode-labeled peptide-major histocompatibility complex I multimers

DEFF Research Database (Denmark)

Bentzen, Amalie Kai; Marquard, Andrea Marion; Lyngaa, Rikke Birgitte

2016-01-01

sample using >1000 different peptide-MHC multimers labeled with individual DNA barcodes.After isolation of MHC multimer binding T cells their recognition are revealed by amplification andsequencing of the MHC multimer-associated DNA barcodes. The relative frequency of the sequencedDNA barcodes...... originating from a given peptide-MHC motif relates to the size of the antigenresponsiveT cell population. We have demonstrated the use of large panels of >1000 DNA barcodedMHC multimers for detection of rareT cell populations of virus and cancer-restricted origin in various tissues and compared...

Aging and ABO blood type influence von Willebrand factor and factor VIII levels through interrelated mechanisms.

Science.gov (United States)

Albánez, S; Ogiwara, K; Michels, A; Hopman, W; Grabell, J; James, P; Lillicrap, D

2016-05-01

Essentials von Willebrand factor (VWF) and factor VIII (FVIII) levels are modulated by age and ABO status. The effect of aging and ABO blood type on VWF and FVIII was assessed in 207 normal individuals. Aging and ABO blood type showed combined and bidirectional influences on VWF and FVIII levels. Aging and ABO blood type influence VWF levels through both secretion and clearance mechanisms. Background The effect of aging and ABO blood type on plasma levels of von Willebrand factor (VWF) and factor VIII (FVIII) have been widely reported; however, a comprehensive analysis of their combined effect has not been performed and the mechanisms responsible for the age-related changes have not been determined. Objectives To assess the influence of aging and ABO blood type on VWF and FVIII levels, and to evaluate the contribution of VWF secretion and clearance to the age-related changes. Methods A cross-sectional observational study was performed in a cohort of 207 normal individuals, whose levels of VWF, FVIII, VWF propeptide (VWFpp), VWFpp/VWF:Ag ratio and blood type A antigen content on VWF (A-VWF) were quantified. Results Aging and ABO blood type exerted interrelated effects on VWF and FVIII plasma levels, because the age-related increase in both proteins was significantly higher in type non-O individuals (β = 0.011 vs. 0.005). This increase with age in non-O subjects drove the differences between blood types in VWF levels, as the mean difference increased from 0.13 U/mL in the young to 0.57 U/mL in the old. Moreover, A-VWF was associated with both VWF antigen (β = 0.29; 95% confidence interval [CI], 0.09, 0.50) and VWF clearance (β = -0.15; 95% CI, -0.25, -0.06). We also documented an effect of ABO blood type on VWF secretion with aging, as old individuals with blood type non-O showed higher levels of VWFpp (mean difference 0.29 U/mL). Conclusions Aging and ABO blood type have an interrelated effect on VWF and FVIII levels, where the effect of one is significantly

Antibody Stabilization of Peptide–MHC Multimers Reveals Functional T Cells Bearing Extremely Low-Affinity TCRs

DEFF Research Database (Denmark)

Tungatt, Katie; Bianchi, Valentina; Crowther, Michael D

2015-01-01

Fluorochrome-conjugated peptide-MHC (pMHC) multimers are commonly used in combination with flow cytometry for direct ex vivo visualization and characterization of Ag-specific T cells, but these reagents can fail to stain cells when TCR affinity and/or TCR cell-surface density are low. pMHC multim...

Influences of ABO blood group, age and gender on plasma coagulation factor VIII, fibrinogen, von Willebrand factor and ADAMTS13 levels in a Chinese population.

Science.gov (United States)

Wang, Zongkui; Dou, Miaomiao; Du, Xi; Ma, Li; Sun, Pan; Cao, Haijun; Ye, Shengliang; Jiang, Peng; Liu, Fengjuan; Lin, Fangzhao; Zhang, Rong; Li, Changqing

2017-01-01

ABO blood group is a hereditary factor of plasma levels of coagulation factor VIII (FVIII) and von Willebrand factor (VWF). Age and gender have been shown to influence FVIII, VWF, fibrinogen (Fbg), and ADAMTS13 (A disintegrin and metalloprotease with thrombospondin type 1 motif, 13). We investigated the effects of ABO type, age, and gender on plasma levels of FVIII, Fbg, VWF, and ADAMTS13 in a Chinese population. A total of 290 healthy volunteers were eligible for this study. ABO blood group was determined by indirect technique. FVIII:C and Fbg were measured by clotting assays. VWF antigen (VWF:Ag), collagen-binding activity (VWF:CBA), and ADAMTS13 antigen were assessed by ELISA, whereas VWF ristocetin cofactor activity (VWF:Rcof) was performed by agglutination of platelets with ristocetin. Mean FVIII:C and VWF levels (VWF:Ag, VWF:CBA, and VWF:Rcof) were significantly higher in non-O than in O type subjects ( p  blood group, age, and gender showed different effects on plasma levels of FVIII:C, Fbg, VWF:Ag, VWF:CBA, VWF:Rcof, and ADAMTS13 antigen. These new data on a Chinese population are quite helpful to compare with other ethnic groups.

Du laboratoire audio au laboratoire multimédia

Directory of Open Access Journals (Sweden)

Béatrice Vautherin

2000-01-01

Full Text Available Les évolutions technologiques récentes amènent les enseignants de langues à faire des choix pour intégrer les outils multimédias dans leur pratique. Les investissements qu'implique cette modernisation, tant en termes de budgets qu'en termes de formation des utilisateurs, nécessitent que ces choix soient éclairés. La complexité du domaine appelle la fédération des compétences et la circulation de l'information pour surmonter les obstacles les plus fréquents. On trouvera ci-dessous une contribution à ce débat sous la forme d'un état des lieux dans une université spécialisée dans les langues et de l'examen détaillé d'un aspect particulier assez épineux, mais incontournable, la création de cours multimédias à partir de matériau pédagogique existant.

High-throughput discovery of T cell epitopes in type 1 diabetes using DNA barcode labelledpeptide-MHC multimers

DEFF Research Database (Denmark)

Lyngaa, Rikke Birgitte; Bentzen, Amalie Kai; Overgaard, A. Julie

2016-01-01

applying a novel technology where the selection of MHC-multimer binding T cells is followed by amplification and sequencing of MHC multimer-associated DNA barcodes revealing their recognition. This technique enables simultaneous detection of >1000 specificities. Identifying post translational modifications...

Performance related factors are the main determinants of the von Willebrand factor response to exhaustive physical exercise

NARCIS (Netherlands)

J.E. van Loon (Janine ); M.A.H. Sonneveld (Michelle); S.F.E. Praet (Stephan); M.P.M. de Maat (Moniek); F.W.G. Leebeek (Frank)

2014-01-01

textabstractBackground: Physical stress triggers the endothelium to release von Willebrand Factor (VWF) from the Weibel Palade bodies. Since VWF is a risk factor for arterial thrombosis, it is of great interest to discover determinants of VWF response to physical stress. We aimed to determine the

Um guia de recomendações para o emprego de dados multimídia em sites web

OpenAIRE

Correa, Rodrigo Stéfani

2002-01-01

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência da Computação. Com a evolução do suporte tecnológico da Web/Internet, surgiram diversos sites web multimídia. Atualmente existem poucos trabalhos voltados à orientação dos desenvolvedores quanto ao uso adequado dos dados multimídia. Este trabalho propõe um guia de recomendações para o emprego de dados multimídia para auxiliar o projeto de sites web. Para alcançar os obj...

Increased active von Willebrand factor during disease development in the aging diabetic patient population.

Science.gov (United States)

Chen, Shuang Feng; Xia, Zuo Li; Han, Ji Ju; Wang, Yi Ting; Wang, Ji Yue; Pan, Shao Dong; Wu, Ya Ping; Zhang, Bin; Li, Guang Yao; Du, Jing Wei; Gao, Hen Qiang; de Groot, Philip G; de Laat, Bas; Hollestelle, Martine J

2013-02-01

Type 2 diabetes is known to cause endothelial activation resulting in the secretion of von Willebrand factor (VWF). We have shown that levels of VWF in a glycoprotein Ib-binding conformation are increased in specific clinical settings. The aim of the current study is to investigate whether active VWF levels increase during aging and the development of diabetes within the population of patients suffering from type 2 diabetes. Patients and controls were divided into two groups based on age: older and younger than 60 years of age. VWF antigen, VWF propeptide, VWF activation factor and total active VWF were measured. Patients older than 60 years of age had increased levels of total active VWF, VWF activation factor and VWF propeptide compared to younger patients and controls. All measured VWF parameters were associated with age in diabetic patients. Total active VWF and VWF propeptide correlated with the period of being diagnosed with diabetes. Regression analyses showed that especially the VWF activation factor was strongly associated with diabetes in patients older than 60 years of age. In conclusion, we found that the conformation of VWF could be involved in the disease process of diabetes and that the VWF in a glycoprotein Ib-binding conformation could play a role as risk marker during the development of diabetes in combination with an increase in age. Our study shows that the active quality of VWF was more important than the quantity.

Performance related factors are the main determinants of the von Willebrand factor response to exhaustive physical exercise.

Directory of Open Access Journals (Sweden)

Janine E van Loon

Full Text Available Physical stress triggers the endothelium to release von Willebrand Factor (VWF from the Weibel Palade bodies. Since VWF is a risk factor for arterial thrombosis, it is of great interest to discover determinants of VWF response to physical stress. We aimed to determine the main mediators of the VWF increase by exhaustive physical exercise.105 healthy individuals (18-35 years were included in this study. Each participant performed an incremental exhaustive exercise test on a cycle ergometer. Respiratory gas exchange measurements were obtained while cardiac function was continuously monitored. Blood was collected at baseline and directly after exhaustion. VWF antigen (VWF:Ag levels, VWF collagen binding (VWF:CB levels, ADAMTS13 activity and common variations in Syntaxin Binding Protein-5 (STXBP5, rs1039084 and rs9399599, Syntaxin-2 (STX2, rs7978987 and VWF (promoter, rs7965413 were determined.The median VWF:Ag level at baseline was 0.94 IU/mL [IQR 0.8-1.1] and increased with 47% [IQR 25-73] after exhaustive exercise to a median maximum VWF:Ag of 1.38 IU/mL [IQR 1.1-1.8] (p<0.0001. VWF:CB levels and ADAMTS13 activity both also increased after exhaustive exercise (median increase 43% and 12%, both p<0.0001. The strongest determinants of the VWF:Ag level increase are performance related (p<0.0001. We observed a gender difference in VWF:Ag response to exercise (females 1.2 IU/mL; males 1.7 IU/mL, p = 0.001, which was associated by a difference in performance. Genetic variations in STXBP5, STX2 and the VWF promoter were not associated with VWF:Ag levels at baseline nor with the VWF:Ag increase.VWF:Ag levels strongly increase upon exhaustive exercise and this increase is strongly determined by physical fitness level and the intensity of the exercise, while there is no clear effect of genetic variation in STXBP5, STX2 and the VWF promoter.

Performance related factors are the main determinants of the von Willebrand factor response to exhaustive physical exercise.

Science.gov (United States)

van Loon, Janine E; Sonneveld, Michelle A H; Praet, Stephan F E; de Maat, Moniek P M; Leebeek, Frank W G

2014-01-01

Physical stress triggers the endothelium to release von Willebrand Factor (VWF) from the Weibel Palade bodies. Since VWF is a risk factor for arterial thrombosis, it is of great interest to discover determinants of VWF response to physical stress. We aimed to determine the main mediators of the VWF increase by exhaustive physical exercise. 105 healthy individuals (18-35 years) were included in this study. Each participant performed an incremental exhaustive exercise test on a cycle ergometer. Respiratory gas exchange measurements were obtained while cardiac function was continuously monitored. Blood was collected at baseline and directly after exhaustion. VWF antigen (VWF:Ag) levels, VWF collagen binding (VWF:CB) levels, ADAMTS13 activity and common variations in Syntaxin Binding Protein-5 (STXBP5, rs1039084 and rs9399599), Syntaxin-2 (STX2, rs7978987) and VWF (promoter, rs7965413) were determined. The median VWF:Ag level at baseline was 0.94 IU/mL [IQR 0.8-1.1] and increased with 47% [IQR 25-73] after exhaustive exercise to a median maximum VWF:Ag of 1.38 IU/mL [IQR 1.1-1.8] (pexercise (median increase 43% and 12%, both pexercise (females 1.2 IU/mL; males 1.7 IU/mL, p = 0.001), which was associated by a difference in performance. Genetic variations in STXBP5, STX2 and the VWF promoter were not associated with VWF:Ag levels at baseline nor with the VWF:Ag increase. VWF:Ag levels strongly increase upon exhaustive exercise and this increase is strongly determined by physical fitness level and the intensity of the exercise, while there is no clear effect of genetic variation in STXBP5, STX2 and the VWF promoter.

Safety, tolerability, pharmacokinetics and pharmacodynamics of anti-VWF nanobody® ALX-0681 after single and multiple subcutaneous administrations to healthy volunteers

NARCIS (Netherlands)

Abd-Elaziz, Khalid; Kamphuisen, Pieter W; Lyssens, Christophe; Reuvers, Mariska; Den Daas, Izaak; Van Bockstaele, Femke; Vercruysse, Kristof; Ulrichts, Hans; Baumeister, Judith; Crabbe, Patricia; Compernolle, Veerle; Holz, Josefin-Beate

2009-01-01

ALX-0681 is a humanized bivalent Nanobody®, that binds to the A1 domain of von Willebrand factor (vWF) and hence blocks its interaction with platelet receptor GPIb-IX-V. Given its mode of action, ALX-0681 could provide an alternative treatment option for thrombotic thrombocytopenic purpura (TTP), a

Storage of factor VIII variants with impaired von Willebrand factor binding in Weibel-Palade bodies in endothelial cells.

Directory of Open Access Journals (Sweden)

Maartje van den Biggelaar

Full Text Available BACKGROUND: Point mutations resulting in reduced factor VIII (FVIII binding to von Willebrand factor (VWF are an important cause of mild/moderate hemophilia A. Treatment includes desmopressin infusion, which concomitantly increases VWF and FVIII plasma levels, apparently from storage pools containing both proteins. The source of these VWF/FVIII co-storage pools and the mechanism of granule biogenesis are not fully understood. METHODOLOGY/PRINCIPAL FINDINGS: We studied intracellular trafficking of FVIII variants implicated in mild/moderate hemophilia A together with VWF in HEK293 cells and primary endothelial cells. The role of VWF binding was addressed using FVIII variants displaying reduced VWF interaction. Binding studies using purified FVIII proteins revealed moderate (Arg2150His, Del2201, Pro2300Ser to severe (Tyr1680Phe, Ser2119Tyr VWF binding defects. Expression studies in HEK293 cells and primary endothelial cells revealed that all FVIII variants were present within VWF-containing organelles. Quantitative studies showed that the relative amount of FVIII storage was independent of various mutations. Substantial amounts of FVIII variants are co-stored in VWF-containing storage organelles, presumably by virtue of their ability to interact with VWF at low pH. CONCLUSIONS: Our data suggest that the potential of FVIII co-storage with VWF is not affected in mild/moderate hemophilia A caused by reduced FVIII/VWF interaction in the circulation. These data support the hypothesis that Weibel-Palade bodies comprise the desmopressin-releasable FVIII storage pool in vivo.

A critical assessment for the value of markers to gate-out undesired events in HLA-peptide multimer staining protocols

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Odunsi Kunle

2011-07-01

Full Text Available Abstract Background The introduction of antibody markers to identify undesired cell populations in flow-cytometry based assays, so called DUMP channel markers, has become a practice in an increasing number of labs performing HLA-peptide multimer assays. However, the impact of the introduction of a DUMP channel in multimer assays has so far not been systematically investigated across a broad variety of protocols. Methods The Cancer Research Institute's Cancer Immunotherapy Consortium (CRI-CIC conducted a multimer proficiency panel with a specific focus on the impact of DUMP channel use. The panel design allowed individual laboratories to use their own protocol for thawing, staining, gating, and data analysis. Each experiment was performed twice and in parallel, with and without the application of a dump channel strategy. Results The introduction of a DUMP channel is an effective measure to reduce the amount of non-specific MULTIMER binding to T cells. Beneficial effects for the use of a DUMP channel were observed across a wide range of individual laboratories and for all tested donor-antigen combinations. In 48% of experiments we observed a reduction of the background MULTIMER-binding. In this subgroup of experiments the median background reduction observed after introduction of a DUMP channel was 0.053%. Conclusions We conclude that appropriate use of a DUMP channel can significantly reduce background staining across a large fraction of protocols and improve the ability to accurately detect and quantify the frequency of antigen-specific T cells by multimer reagents. Thus, use of a DUMP channel may become crucial for detecting low frequency antigen-specific immune responses. Further recommendations on assay performance and data presentation guidelines for publication of MULTIMER experimental data are provided.

Adaptive evolution of the venom-targeted vWF protein in opossums that eat pitvipers.

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Sharon A Jansa

Full Text Available The rapid evolution of venom toxin genes is often explained as the result of a biochemical arms race between venomous animals and their prey. However, it is not clear that an arms race analogy is appropriate in this context because there is no published evidence for rapid evolution in genes that might confer toxin resistance among routinely envenomed species. Here we report such evidence from an unusual predator-prey relationship between opossums (Marsupialia: Didelphidae and pitvipers (Serpentes: Crotalinae. In particular, we found high ratios of replacement to silent substitutions in the gene encoding von Willebrand Factor (vWF, a venom-targeted hemostatic blood protein, in a clade of opossums known to eat pitvipers and to be resistant to their hemorrhagic venom. Observed amino-acid substitutions in venom-resistant opossums include changes in net charge and hydrophobicity that are hypothesized to weaken the bond between vWF and one of its toxic snake-venom ligands, the C-type lectin-like protein botrocetin. Our results provide the first example of rapid adaptive evolution in any venom-targeted molecule, and they support the notion that an evolutionary arms race might be driving the rapid evolution of snake venoms. However, in the arms race implied by our results, venomous snakes are prey, and their venom has a correspondingly defensive function in addition to its usual trophic role.

Regulation of plasma von Willebrand factor [version 1; referees: 3 approved

Directory of Open Access Journals (Sweden)

Karl C Desch

2018-01-01

Full Text Available Von Willebrand factor (VWF is a multimeric plasma glycoprotein that plays a central role in the initiation of blood coagulation. Through interactions between its specific functional domains, the vascular wall, coagulation factor VIII, and platelet receptors, VWF maintains hemostasis by binding to platelets and delivering factor VIII to the sites of vascular injury. In the healthy human population, plasma VWF levels vary widely. The important role of VWF is illustrated by individuals at the extremes of the normal distribution of plasma VWF concentrations where individuals with low VWF levels are more likely to present with mucocutaneous bleeding. Conversely, people with high VWF levels are at higher risk for venous thromboembolic disease, stroke, and coronary artery disease. This report will summarize recent advances in our understanding of environmental influences and the genetic control of VWF plasma variation in healthy and symptomatic populations and will also highlight the unanswered questions that are currently driving this field of study.

Profile of von Willebrand factor antigen and von Willebrand factor propeptide in an overall TIA and ischaemic stroke population and amongst subtypes.

Science.gov (United States)

Tobin, W O; Kinsella, J A; Kavanagh, G F; O'Donnell, J S; McGrath, R T; Tierney, S; Egan, B; Feeley, T M; Coughlan, T; Collins, D R; O'Neill, D; Murphy, Sjx; Lim, S J; Murphy, R P; McCabe, Djh

2017-04-15

Von Willebrand factor propeptide (VWF:Ag II) is proposed to be a more sensitive marker of acute endothelial activation than von Willebrand factor antigen (VWF:Ag). Simultaneous data on VWF:Ag and VWF:Ag II profiles are very limited following TIA and ischaemic stroke. In this prospective, observational, case-control study, plasma VWF:Ag and VWF:Ag II levels were quantified in 164 patients≤4weeks of TIA or ischaemic stroke (baseline), and then ≥14days (14d) and ≥90days (90d) later, and compared with those from 27 healthy controls. TIA and stroke subtyping was performed according to the TOAST classification. The relationship between VWF:Ag and VWF:Ag II levels and platelet activation status was assessed. 'Unadjusted' VWF:Ag and VWF:Ag II levels were higher in patients at baseline, 14d and 90d than in controls (p≤0.03). VWF:Ag levels remained higher in patients than controls at baseline (p≤0.03), but not at 14d or 90d after controlling for differences in age or hypertension, and were higher in patients at baseline and 90d after controlling for smoking status (p≤0.04). 'Adjusted' VWF:Ag II levels were not higher in patients than controls after controlling for age, hypertension or smoking (p≥0.1). Patients with symptomatic carotid stenosis (N=46) had higher VWF:Ag and VWF:Ag II levels than controls at all time-points (p≤0.002). There was no significant correlation between platelet activation status and VWF:Ag or VWF:Ag II levels. VWF:Ag and VWF:Ag II levels are increased in an overall TIA and ischaemic stroke population, especially in patients with recently symptomatic carotid stenosis. VWF:Ag II was not superior to VWF:Ag at detecting acute endothelial activation in this cohort and might reflect timing of blood sampling in our study. Copyright © 2017 Elsevier B.V. All rights reserved.

Active Von Willebrand Factor, thrombocytopenia and thrombosis

NARCIS (Netherlands)

Hulstein, J.J.J.

2006-01-01

Platelets and von Willebrand factor (VWF) are unable to interact in circulation. To induce an interaction, a conversion of VWF to a platelet-binding conformation is required. At higher shear stresses, the first step in thrombus formation is binding of VWF to the subendothelium. This results in

Detection of von Willebrand factor and tissue factor in platelets-fibrin rich coronary thrombi in acute myocardial infarction.

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Yamashita, Atsushi; Sumi, Takahiro; Goto, Shinya; Hoshiba, Yasunari; Nishihira, Kensaku; Kawamoto, Riichirou; Hatakeyama, Kinta; Date, Haruhiko; Imamura, Takuroh; Ogawa, Hisao; Asada, Yujiro

2006-01-01

The rapid closure of coronary arteries due to occlusive thrombi is the major cause of acute myocardial infarction. However, the mechanisms of coronary thrombus formation have not been elucidated. We immunohistochemically assessed the localizations and their changes over time of glycoprotein IIb/IIIa, fibrin, von Willebrand factor (vWF), and tissue factor (TF), after the onset of chest pain (platelets, fibrin, vWF, and TF from the early phase of onset, and glycoprotein IIb/IIIa and fibrin were closely associated with vWF and TF, respectively. vWF and/or TF may contribute to occlusive thrombus formation and be novel therapeutic candidates for treating patients with coronary thrombosis.

Covalently linked multimers of gold nanoclusters Au102(p-MBA)44 and Au∼250(p-MBA)n.

Science.gov (United States)

Lahtinen, Tanja; Hulkko, Eero; Sokołowska, Karolina; Tero, Tiia-Riikka; Saarnio, Ville; Lindgren, Johan; Pettersson, Mika; Häkkinen, Hannu; Lehtovaara, Lauri

2016-11-10

We present the synthesis, separation, and characterization of covalently-bound multimers of para-mercaptobenzoic acid (p-MBA) protected gold nanoclusters. The multimers were synthesized by performing a ligand-exchange reaction of a pre-characterized Au 102 (p-MBA) 44 nanocluster with biphenyl-4,4'-dithiol (BPDT). The reaction products were separated using gel electrophoresis yielding several distinct bands. The bands were analyzed by transmission electron microscopy (TEM) revealing monomer, dimer, and trimer fractions of the nanocluster. TEM analysis of dimers in combination with molecular dynamics simulations suggest that the nanoclusters are covalently bound via a disulfide bridge between BPDT molecules. The linking chemistry is not specific to Au 102 (p-MBA) 44 . The same approach yields multimers also for a larger monodisperse p-MBA-protected cluster of approximately 250 gold atoms, Au ∼250 (p-MBA) n . While the Au 102 (p-MBA) 44 is not plasmonic, the Au ∼250 (p-MBA) n nanocluster supports localized surface plasmon resonance (LSPR) at 530 nm. Multimers of the Au ∼250 (p-MBA) n exhibit additional transitions in their UV-vis spectrum at 630 nm and 810 nm, indicating the presence of hybridized LSPR modes. Well-defined structures and relatively small sizes make these systems excellent candidates for connecting ab initio theoretical studies and experimental quantum plasmonics. Moreover, our work opens new possibilities in the controlled synthesis of advanced monodisperse nanocluster superstructures.

O multimédia ao serviço das indústrias criativas e culturais

OpenAIRE

Tenazinha, Ana Mafalda Sousa Ligeiro Guerreiro, 1988-

2013-01-01

Dissertação de mestrado em Comunicação Multimédia, Universidade Lusíada de Lisboa, 2013. Exame público realizado em 27 de Junho de 2013. As inovações trazidas ao contexto digital e o multimédia em particular trouxeram múltiplas alterações ao modo de vida contemporâneo. Estas alterações, que se reflectiram directamente na mudança de hábitos sociais e de consumo, trouxeram consigo a reformulação de processos de produção, distribuição e divulgação de bens e serviços em geral. Esta inves...

An ELISA for the quantitation of von Willebrand Factor

DEFF Research Database (Denmark)

Vinholt, Pernille Just; Overgaard, Martin; Diederichsen, Axel Cosmus Pyndt

2013-01-01

for measurement of von Willebrand factor-osteoprotegerin complex (VWF:OPG) in human plasma. Furthermore, the significance of VWF:OPG complex as a marker of cardiovascular disease (CVD) was evaluated. PATIENTS/METHODS: A sandwich ELISA for quantification of VWF:OPG was developed using a polyclonal rabbit anti...... with and without documented coronary calcification (total n=118). RESULTS AND CONCLUSIONS: The assay detected VWF:OPG complexes in human plasma, while no significant signal was observed when testing solutions containing VWF or recombinant OPG alone. Importantly, the ELISA assay was able to detect in vitro formed...

Relationship between ABO blood groups and von Willebrand factor, ADAMTS13 and factor VIII in patients undergoing hemodialysis.

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Rios, Danyelle R A; Fernandes, Ana Paula; Figueiredo, Roberta C; Guimarães, Daniela A M; Ferreira, Cláudia N; Simões E Silva, Ana C; Carvalho, Maria G; Gomes, Karina B; Dusse, Luci Maria Sant' Ana

2012-05-01

Several studies have demonstrated that non-O blood groups subjects present an increased VTE risk as compared to those carrying O blood group. The aim of this study was to investigate the ABO blood groups influence on factor VIII (FVIII) activity, von Willebrand factor (VWF), and ADAMTS13 plasma levels in patients undergoing hemodialysis (HD). Patients undergoing HD (N=195) and 80 healthy subjects (control group) were eligible for this cross-sectional study. The ABO blood group phenotyping was performed by the reverse technique. FVIII activity was measured through coagulometric method, and VWF and ADAMTS13 antigens were assessed by ELISA. FVIII activity and VWF levels were significantly higher and ADAMTS13 levels was decreased in HD patients, as compared to healthy subjects (P blood groups showed a significant increase in FVIII activity (P = 0.001) and VWF levels (P blood group. However, no significant difference was observed in ADAMTS13 levels (P = 0.767). In the control group, increased in FVIII activity (P = 0.001) and VWF levels (P = 0.002) and decreased in ADAMTS13 levels (P = 0.005) were observed in subjects carrying non-O blood groups as compared to carriers of O blood group.Our data confirmed that ABO blood group is an important risk factor for increased procoagulant factors in plasma, as FVIII and VWF. Admitting the possible role of kidneys in ADAMTS13 synthesis or on its metabolism, HD patients were not able to increase ADAMTS13 levels in order to compensate the increase of VWF levels mediated by ABO blood groups. Considering that non-O blood groups constitute a risk factor for thrombosis, it is reasonable to admit that A, B and AB HD patients need a careful and continuous follow-up in order to minimize thrombotic events.

Association of ABO blood groups with von Willebrand factor, factor VIII and ADAMTS-13 in patients with lung cancer.

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Liu, Xia; Chen, Xiaogang; Yang, Jiezuan; Guo, Renyong

2017-09-01

Coagulative and fibrinolytic disorders appear to be associated with the development of lung cancer. The aim of the present study was to determine plasma levels of von Willebrand factor (VWF) and a disintegrin and metalloproteinase with a thrombospondin type 1 motif 13 (ADAMTS-13), and factor VIII (FVIII) activity, in association with O and non-O blood groups in patients with lung cancer. Plasma levels of VWF and ADAMTS-13, and FVIII activity were measured in 115 patients with lung cancer and 98 healthy subjects. Phenotyping of the ABO blood groups was also performed for the two groups. Significantly increased VWF levels and FVIII activity, as well as significantly decreased ADAMTS-13 levels, were observed in patients with distant metastasis as compared with those without distant metastasis and the healthy controls. Plasma VWF levels and FVIII activity were significantly increased in subjects with non-O type blood compared with those with type O blood in the two groups. However, a significant decrease in ADAMTS-13 levels was observed only in the control group among those with non-O type blood, compared with those with type O blood. The results of the present study indicate that increased VWF and decreased ADAMTS-13 levels facilitate the invasiveness and metastasis of lung cancer. Non-O blood groups constitute a risk factor for increased VWF and FVIII in plasma. Continued monitoring of VWF and ADAMTS-13 levels, and of FVIII activity in patients with lung cancer with distinct blood groups may help to minimize the incidence of thrombotic events and improve assessment of disease progression.

Reduced ADAMTS13 activity is associated with thrombotic risk in systemic lupus erythematosus.

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Martin-Rodriguez, S; Reverter, J C; Tàssies, D; Espinosa, G; Heras, M; Pino, M; Escolar, G; Diaz-Ricart, M

2015-10-01

Severe deficiency of ADAMTS13 activity leads to von Willebrand factor (VWF) ultralarge multimers with high affinity for platelets, causing thrombotic thrombocytopenic purpura. Other pathological conditions with moderate ADAMTS13 activity exhibit a thrombotic risk. We examined the ADAMTS13 activity in systemic lupus erythematosus (SLE) and its value as a thrombotic biomarker. ADAMTS13 activity, VWF antigen and multimeric structure, and vascular cell adhesion molecule 1 (VCAM-1) were measured in plasma samples from 50 SLE patients and 50 healthy donors. Disease activity (systemic lupus erythematosus disease activity index; SLEDAI) and organ damage (systemic lupus international collaborating clinics) scores, thrombotic events, antiphospholipid syndrome (APS) and antiphospholipid antibodies (aPLs) were registered. SLE patients showed decreased ADAMTS13 activity and high VWF levels compared with controls (66 ± 27% vs. 101 ± 8%, P 60%, 60-40% and <40%), comparative analysis showed significant association between ADAMTS13 activity and SLEDAI (P < 0.05), presence of aPLs (P < 0.001), APS (P < 0.01) and thrombotic events (P < 0.01). Reduced ADAMTS13 activity together with increased VWF levels were especially notable in patients with active disease and with aPLs. ADAMTS13 activity, in combination with other laboratory parameters, could constitute a potential prognostic biomarker of thrombotic risk in SLE. © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

[Homocysteine and von Willebrand factor in chronic alcoholism].

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Koriakin, A M; Epifantseva, N N; Dadyka, I V; Gorbatovskiĭ, Ia A

2010-04-01

The levels of homocysteine (HC) and von Willebrand factor (VWF) as cardiovascular risk factors were studied in patients with Stage II chronic alcoholism. Forty-one men with Stage II chronic alcoholism without clinical signs of somatic and infectious diseases were examined. Their median age was 37 (range 32-40) years; the alcoholization period was 12 (range 8-17) years. Plasma HC and VWF (amount and activity) levels were determined. In 63.4% of chronic alcoholic patients, HC levels was twice as high as in the controls; in 80.6%, both the content and activity of VWF were increased. There was no correlation between the levels of HC and VWF. Vascular endothelial damage concurrent with hyperhomocysteinemia increases a cardiovascular risk in patients with Stage II chronic alcoholism.

Factors influencing the recycling rate under the volume-based waste fee system in South Korea.

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Park, Seejeen

2018-04-01

Since the early 2000s, the Republic of Korea (South Korea) has maintained its top-rank status for its municipal solid waste (MSW) recycling rate among OECD (Organization for Economic Cooperation and Development) member countries. The volume-based waste fee system (VWF) has been considered to be the major factor contributing to the high recycling performance, and extant research has verified the positive relationship between VWF adoption and the MSW recycling rate. Nevertheless, there exists a gap in the literature, as past research has focused more on testing the positive effects of VWF rather than on investigating the determinants of recycling rates after the adoption of VWF. The current study seeks to address this gap by investigating the various factors that affect recycling rates under the VWF system. More specifically, using data from 16 regions in South Korea over a period of 11 years, this study empirically tests the effects of VWF pricing, the citizen cost burden ratio for the VWF system, and pro-environmental behavior related to VWF on the recycling rate. The findings indicate that economic incentives such as cost savings on VWF plastic bag purchases and reduced burden from paying VWF expenses result in higher recycling rates. The findings also demonstrate that pro-environmental behavior in the VWF context positively affects the recycling rate. Copyright © 2018 Elsevier Ltd. All rights reserved.

von Willebrand factor, Jedi knight of the bloodstream.

Science.gov (United States)

Springer, Timothy A

2014-08-28

When blood vessels are cut, the forces in the bloodstream increase and change character. The dark side of these forces causes hemorrhage and death. However, von Willebrand factor (VWF), with help from our circulatory system and platelets, harnesses the same forces to form a hemostatic plug. Force and VWF function are so closely intertwined that, like members of the Jedi Order in the movie Star Wars who learn to use "the Force" to do good, VWF may be considered the Jedi knight of the bloodstream. The long length of VWF enables responsiveness to flow. The shape of VWF is predicted to alter from irregularly coiled to extended thread-like in the transition from shear to elongational flow at sites of hemostasis and thrombosis. Elongational force propagated through the length of VWF in its thread-like shape exposes its monomers for multimeric binding to platelets and subendothelium and likely also increases affinity of the A1 domain for platelets. Specialized domains concatenate and compact VWF during biosynthesis. A2 domain unfolding by hydrodynamic force enables postsecretion regulation of VWF length. Mutations in VWF in von Willebrand disease contribute to and are illuminated by VWF biology. I attempt to integrate classic studies on the physiology of hemostatic plug formation into modern molecular understanding, and point out what remains to be learned. © 2014 by The American Society of Hematology.

Investigación intervención y enfoque multimétodo en Ciencias Humanas y educación matemática

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Henry de Jesús Gallardo Pérez

2017-10-01

Full Text Available El artículo tiene como objetivo asociar la investigación intervención y el mentoring implementada en ciencias humanas en la educación matemática, así mismo analiza el multimétodo como enfoque de investigación en educación matemática. La investigación implementa microproyectos y mentoring, la información se analiza a través de triangulación de métodos de análisis factorial e investigación intervención. Resultados: cognición social, interacción empática, adicciones, apoyo padres son factores asociados a pensamiento matemático, intervención a través de apoyo psicopedagógico mejoró desarrollo del pensamiento. Conclusión: La investigación intervención como método dentro del enfoque multimétodo presenta una alternativa de acercamiento a la comprensión de las situación educativa y de los diferentes factores asociados para desde allí formular propuestas que permitan al estudiante alcanzar un nivel competente en el aprendizaje, comprensión y aplicación de las matemáticas que responda positivamente a su actuar en su mundo natural.

Clinical experience with Optivate®, high-purity factor VIII (FVIII) product with von Willebrand factor (VWF) in young children with haemophilia A.

Science.gov (United States)

Matysiak, M; Bobrowska, H; Balwierz, W; Chybicka, A; Kowalczyk, J R; Shaikh-Zaidi, R; Gillanders, K; Dash, C H

2011-09-01

Optivate® is a high-purity FVIII/VWF product. Its safety, tolerability and efficacy in subjects ≥ 12 years have been demonstrated. This study was undertaken to assess Optivate® in children with haemophilia A. Twenty-five children, including one PUP (previously untreated patient), aged 1-6 years (mean 4.67 years) were treated with Optivate® for 26 weeks. Inhibitors were assessed every 3 months and viral status at the study start and end. Prophylaxis was used by five boys and on demand by twenty. The mean number of bleeds in the study was lower compared to the same period pre-study (12.0/child vs. 16.2/child), with fewer bleeds (P related events (5%), all were mild and non-serious. There were no clinically significant changes in vital signs, viral transmissions or inhibitors. In young children Optivate® was well tolerated, safe and efficacious. © 2011 Blackwell Publishing Ltd.

Dynamics of von Willebrand factor reactivity in sickle cell disease during vaso-occlusive crisis and steady state

NARCIS (Netherlands)

Sins, J. W.R.; Schimmel, Marein; Luken, Brenda M.; Nur, Erfan; Zeerleder, S.; van Tuijn, Charlotte F. J.; Brandjes, Dees P. M.; Kopatz, W. F.; Urbanus, R. T.; Meijers, Joost C. M.; Biemond, B. J.; Fijnvandraat, K.

2017-01-01

Essentials The role of von Willebrand Factor (VWF) in the pathophysiology of sickle cell disease is unclear. We assessed markers of VWF during admission for vaso-occlusive crisis (VOC) and steady state. VWF reactivity was higher during VOC and was associated with inflammation and neutrophil

Endothelial activation markers (VCAM-1, vWF in patients with chronic hepatitis C and insulin resistance

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T. V. Antonova

2012-01-01

Full Text Available Blood markers of endothelial activation (sVCAM-1, vWF: Ag in patients with chronic hepatitis C in the presence of insulin resistance, metabolic syndrome and its components had been evaluated. The study included 69 patients with chronic hepatitis C with oligosymptomatic the disease. In one third of cases of chronic hepatitis C (33.3% showed improvement in the blood content of sVCAM-1 and / or vWF: Ag. In patients with chronic hepatitis C with insulin resistance, metabolic syndrome significantly more often found signs adhesion of endothelial dysfunction (increased blood concentrations of sVCAM-1 than in patients without these disorders. Found that in patients with severe hepatic fibrosis in patients with chronic hepatitis C blood concentration sVCAM-1 is significantly higher compared to patients with early stages of fibrosis (F0-F2, including those in patients without insulin resistance. These data suggest the multivariate development of endothelial dysfunction in chronic hepatitis C.

Narrativas multimídia de aprendizagem de língua inglesa

OpenAIRE

Menezes, Vera

2010-01-01

Este texto apresenta um estudo sobre narrativas multimídia de aprendizagem de língua inglesa, com foco principal nas representações visuais, tendo como suporte teórico a semiótica visual (Kress & van Leeuwen, 2006), a teoria multimodal da comunicação (Kress & van Leeuwen, 2001), a teoria da avaliatividade (Martin & White, 2005) e a teoria das mesclagens conceituais (Fauconnier & Turner, 2002). Foram selecionados Excertos e imagens de um corpus de 20 narrativas, produzidas por alunos do curso ...

N1421K mutation in the glycoprotein Ib binding domain impairs ristocetin- and botrocetin-mediated binding of von Willebrand factor to platelets

DEFF Research Database (Denmark)

Lanke, E.; Kristoffersson, A.C.; Isaksson, C.

2008-01-01

, moderately decreased plasma factor VIII (FVIII) and VWF levels, and disproportionately low-plasma VWF:RCo levels. The patients were found to be heterozygous for the novel N1421K mutation, caused by a 4263C > G transversion in exon 28 of the VWF gene coding for the A1 domain. Botrocetin- and ristocetin-mediated...... binding of plasma VWF to GPIb were reduced in the patients. In vitro mutagenesis and expression in COS-7 cells confirmed the impairment of the mutant in botrocetin- and ristocetin-mediated VWF binding to GPIb. VWF collagen binding capacity was unaffected in plasma from the heterozygous individuals as well...

Increased metastatic potential of tumor cells in von Willebrand factor-deficient mice.

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Terraube, V; Pendu, R; Baruch, D; Gebbink, M F B G; Meyer, D; Lenting, P J; Denis, C V

2006-03-01

The key role played by von Willebrand factor (VWF) in platelet adhesion suggests a potential implication in various pathologies, where this process is involved. In cancer metastasis development, tumor cells interact with platelets and the vessel wall to extravasate from the circulation. As a potential mediator of platelet-tumor cell interactions, VWF could influence this early step of tumor spread and therefore play a role in cancer metastasis. To investigate whether VWF is involved in metastasis development. In a first step, we characterized the interaction between murine melanoma cells B16-BL6 and VWF in vitro. In a second step, an experimental metastasis model was used to compare the formation of pulmonary metastatic foci in C57BL/6 wild-type and VWF-null mice following the injection of B16-BL6 cells or Lewis lung carcinoma cells. In vitro adhesion assays revealed that VWF is able to promote a dose-dependent adhesion of B16-BL6 cells via its Arg-Gly-Asp (RGD) sequence. In the experimental metastasis model, we found a significant increase in the number of pulmonary metastatic foci in VWF-null mice compared with the wild-type mice, a phenotype that could be corrected by restoring VWF plasma levels. We also showed that increased survival of the tumor cells in the lungs during the first 24 h in the absence of VWF was the cause of this increased metastasis. These findings suggest that VWF plays a protective role against tumor cell dissemination in vivo. Underlying mechanisms remain to be investigated.

Of von Willebrand factor and platelets.

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Bryckaert, Marijke; Rosa, Jean-Philippe; Denis, Cécile V; Lenting, Peter J

2015-01-01

Hemostasis and pathological thrombus formation are dynamic processes that require multiple adhesive receptor-ligand interactions, with blood platelets at the heart of such events. Many studies have contributed to shed light on the importance of von Willebrand factor (VWF) interaction with its platelet receptors, glycoprotein (GP) Ib-IX-V and αIIbβ3 integrin, in promoting primary platelet adhesion and aggregation following vessel injury. This review will recapitulate our current knowledge on the subject from the rheological aspect to the spatio-temporal development of thrombus formation. We will also discuss the signaling events generated by VWF/GPIb-IX-V interaction, leading to platelet activation. Additionally, we will review the growing body of evidence gathered from the recent development of pathological mouse models suggesting that VWF binding to GPIb-IX-V is a promising target in arterial and venous pathological thrombosis. Finally, the pathological aspects of VWF and its impact on platelets will be addressed.

Elevated plasma factor VIII enhances venous thrombus formation in rabbits: contribution of factor XI, von Willebrand factor and tissue factor.

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Sugita, Chihiro; Yamashita, Atsushi; Matsuura, Yunosuke; Iwakiri, Takashi; Okuyama, Nozomi; Matsuda, Shuntaro; Matsumoto, Tomoko; Inoue, Osamu; Harada, Aya; Kitazawa, Takehisa; Hattori, Kunihiro; Shima, Midori; Asada, Yujiro

2013-07-01

Elevated plasma levels of factor VIII (FVIII) are associated with increased risk of deep venous thrombosis. The aim of this study is to elucidate how elevated FVIII levels affect venous thrombus formation and propagation in vivo. We examined rabbit plasma FVIII activity, plasma thrombin generation, whole blood coagulation, platelet aggregation and venous wall thrombogenicity before and one hour after an intravenous infusion of recombinant human FVIII (rFVIII). Venous thrombus induced by the endothelial denudation of rabbit jugular veins was histologically assessed. Thrombus propagation was evaluated as indocyanine green fluorescence intensity. Argatroban, a thrombin inhibitor, and neutralised antibodies for tissue factor (TF), factor XI (FXI), and von Willebrand factor (VWF) were infused before or after thrombus induction to investigate their effects on venous thrombus formation or propagation. Recombinant FVIII (100 IU/kg) increased rabbit plasma FVIII activity two-fold and significantly enhanced whole blood coagulation and total plasma thrombin generation, but did not affect initial thrombin generation time, platelet aggregation and venous wall thrombogenicity. The rFVIII infusion also increased the size of venous thrombus 1 hour after thrombus induction. Argatroban and the antibodies for TF, FXI or VWF inhibited such enhanced thrombus formation and all except TF suppressed thrombus propagation. In conclusion, elevated plasma FVIII levels enhance venous thrombus formation and propagation. Excess thrombin generation by FXI and VWF-mediated FVIII recruitment appear to contribute to the growth of FVIII-driven venous thrombus.

Space and Time Resolved Detection of Platelet Activation and von Willebrand Factor Conformational Changes in Deep Suspensions.

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Biasetti, Jacopo; Sampath, Kaushik; Cortez, Angel; Azhir, Alaleh; Gilad, Assaf A; Kickler, Thomas S; Obser, Tobias; Ruggeri, Zaverio M; Katz, Joseph

2017-01-01

Tracking cells and proteins' phenotypic changes in deep suspensions is critical for the direct imaging of blood-related phenomena in in vitro replica of cardiovascular systems and blood-handling devices. This paper introduces fluorescence imaging techniques for space and time resolved detection of platelet activation, von Willebrand factor (VWF) conformational changes, and VWF-platelet interaction in deep suspensions. Labeled VWF, platelets, and VWF-platelet strands are suspended in deep cuvettes, illuminated, and imaged with a high-sensitivity EM-CCD camera, allowing detection using an exposure time of 1 ms. In-house postprocessing algorithms identify and track the moving signals. Recombinant VWF-eGFP (rVWF-eGFP) and VWF labeled with an FITC-conjugated polyclonal antibody are employed. Anti-P-Selectin FITC-conjugated antibodies and the calcium-sensitive probe Indo-1 are used to detect activated platelets. A positive correlation between the mean number of platelets detected per image and the percentage of activated platelets determined through flow cytometry is obtained, validating the technique. An increase in the number of rVWF-eGFP signals upon exposure to shear stress demonstrates the technique's ability to detect breakup of self-aggregates. VWF globular and unfolded conformations and self-aggregation are also observed. The ability to track the size and shape of VWF-platelet strands in space and time provides means to detect pro- and antithrombotic processes.

Elevated Factor VIII and von Willebrand Factor Levels Predict Unfavorable Outcome in Stroke Patients Treated with Intravenous Thrombolysis

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Noémi Klára Tóth

2018-01-01

Full Text Available IntroductionPlasma factor VIII (FVIII and von Willebrand factor (VWF levels have been associated with the rate and severity of arterial thrombus formation and have been linked to outcomes following thrombolytic therapy in acute myocardial infarction patients. Here, we aimed to investigate FVIII and VWF levels during the course of thrombolysis in acute ischemic stroke (AIS patients and to find out whether they predict long-term outcomes.Materials and methodsStudy population included 131 consecutive AIS patients (median age: 69 years, 60.3% men who underwent i.v. thrombolysis with recombinant tissue plasminogen activator (rt-PA. Blood samples were taken on admission, 1 and 24 h after rt-PA administration to measure FVIII activity and VWF antigen levels. Neurological deficit of patients was determined according to the National Institutes of Health Stroke Scale (NIHSS. ASPECT scores were assessed using computer tomography images taken before and 24 h after thrombolysis. Intracranial hemorrhage was classified according to the European Cooperative Acute Stroke Study (ECASS II criteria. Long-term functional outcome was determined at 90 days after the event by the modified Rankin scale (mRS.ResultsVWF levels on admission were significantly elevated in case of more severe AIS [median and IQR values: NIHSS <6:189.6% (151.9–233.2%; NIHSS 6–16: 199.6% (176.4–250.8%; NIHSS >16: 247.8% (199.9–353.8%, p = 0.013]; similar, but non-significant trend was observed for FVIII levels. FVIII and VWF levels correlated well on admission (r = 0.748, p < 0.001 but no significant correlation was found immediately after thrombolysis (r = 0.093, p = 0.299, most probably due to plasmin-mediated FVIII degradation. VWF levels at all investigated occasions and FVIII activity before and 24 h after thrombolysis were associated with worse 24 h post-lysis ASPECT scores. In a binary backward logistic regression analysis including age, gender

Modeling Shear Induced Von Willebrand Factor Binding to Collagen

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Dong, Chuqiao; Wei, Wei; Morabito, Michael; Webb, Edmund; Oztekin, Alparslan; Zhang, Xiaohui; Cheng, Xuanhong

2017-11-01

Von Willebrand factor (vWF) is a blood glycoprotein that binds with platelets and collagen on injured vessel surfaces to form clots. VWF bioactivity is shear flow induced: at low shear, binding between VWF and other biological entities is suppressed; for high shear rate conditions - as are found near arterial injury sites - VWF elongates, activating its binding with platelets and collagen. Based on parameters derived from single molecule force spectroscopy experiments, we developed a coarse-grain molecular model to simulate bond formation probability as a function of shear rate. By introducing a binding criterion that depends on the conformation of a sub-monomer molecular feature of our model, the model predicts shear-induced binding, even for conditions where binding is highly energetically favorable. We further investigate the influence of various model parameters on the ability to predict shear-induced binding (vWF length, collagen site density and distribution, binding energy landscape, and slip/catch bond length) and demonstrate parameter ranges where the model provides good agreement with existing experimental data. Our results may be important for understanding vWF activity and also for achieving targeted drug therapy via biomimetic synthetic molecules. National Science Foundation (NSF),Division of Mathematical Sciences (DMS).

Multiple functions of the von Willebrand Factor A domain in matrilins: secretion, assembly, and proteolysis

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Kanbe Katsuaki

2008-06-01

Full Text Available Abstract The von Willebrand Factor A (vWF A domain is one of the most widely distributed structural modules in cell-matrix adhesive molecules such as intergrins and extracellular matrix proteins. Mutations in the vWF A domain of matrilin-3 cause multiple epiphyseal dysplasia (MED, however the pathological mechanism remains to be determined. Previously we showed that the vWF A domain in matrilin-1 mediates formation of a filamentous matrix network through metal-ion dependent adhesion sites in the domain. Here we show two new functions of the vWF A domain in cartilage-specific matrilins (1 and 3. First, vWF A domain regulates oligomerization of matrilins. Insertion of a vWF A domain into matrilin-3 converts the formation of a mixture of matrilin-3 tetramer, trimer, and dimer into a tetramer only, while deletion of a vWF A domain from matrilin-1 converts the formation of the native matrilin-1 trimer into a mixture of trimer and dimer. Second, the vWF A domain protects matrilin-1 from proteolysis. We identified a latent proteolytic site next to the vWF A2 domain in matrilin-1, which is sensitive to the inhibitors of matrix proteases. Deletion of the abutting vWF A domain results in degradation of matrilin-1, presumably by exposing the adjacent proteolytic site. In addition, we also confirmed the vWF A domain is vital for the secretion of matrilin-3. Secretion of the mutant matrilin-3 harbouring a point mutation within the vWF A domain, as occurred in MED patients, is markedly reduced and delayed, resulting from intracellular retention of the mutant matrilin-3. Taken together, our data suggest that different mutations/deletions of the vWF A domain in matrilins may lead to distinct pathological mechanisms due to the multiple functions of the vWF A domain.

Complexity in Acid–Base Titrations: Multimer Formation Between Phosphoric Acids and Imines

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Malm, Christian; Kim, Heejae; Wagner, Manfred

2017-01-01

Abstract Solutions of Brønsted acids with bases in aprotic solvents are not only common model systems to study the fundamentals of proton transfer pathways but are also highly relevant to Brønsted acid catalysis. Despite their importance the light nature of the proton makes characterization of acid–base aggregates challenging. Here, we track such acid–base interactions over a broad range of relative compositions between diphenyl phosphoric acid and the base quinaldine in dichloromethane, by using a combination of dielectric relaxation and NMR spectroscopy. In contrast to what one would expect for an acid–base titration, we find strong deviations from quantitative proton transfer from the acid to the base. Even for an excess of the base, multimers consisting of one base and at least two acid molecules are formed, in addition to the occurrence of proton transfer from the acid to the base and simultaneous formation of ion pairs. For equimolar mixtures such multimers constitute about one third of all intermolecular aggregates. Quantitative analysis of our results shows that the acid‐base association constant is only around six times larger than that for the acid binding to an acid‐base dimer, that is, to an already protonated base. Our findings have implications for the interpretation of previous studies of reactive intermediates in organocatalysis and provide a rationale for previously observed nonlinear effects in phosphoric acid catalysis. PMID:28597513

Complexity in Acid-Base Titrations: Multimer Formation Between Phosphoric Acids and Imines.

Science.gov (United States)

Malm, Christian; Kim, Heejae; Wagner, Manfred; Hunger, Johannes

2017-08-10

Solutions of Brønsted acids with bases in aprotic solvents are not only common model systems to study the fundamentals of proton transfer pathways but are also highly relevant to Brønsted acid catalysis. Despite their importance the light nature of the proton makes characterization of acid-base aggregates challenging. Here, we track such acid-base interactions over a broad range of relative compositions between diphenyl phosphoric acid and the base quinaldine in dichloromethane, by using a combination of dielectric relaxation and NMR spectroscopy. In contrast to what one would expect for an acid-base titration, we find strong deviations from quantitative proton transfer from the acid to the base. Even for an excess of the base, multimers consisting of one base and at least two acid molecules are formed, in addition to the occurrence of proton transfer from the acid to the base and simultaneous formation of ion pairs. For equimolar mixtures such multimers constitute about one third of all intermolecular aggregates. Quantitative analysis of our results shows that the acid-base association constant is only around six times larger than that for the acid binding to an acid-base dimer, that is, to an already protonated base. Our findings have implications for the interpretation of previous studies of reactive intermediates in organocatalysis and provide a rationale for previously observed nonlinear effects in phosphoric acid catalysis. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

von Willebrand factor as a novel noninvasive predictor of portal hypertension and esophageal varices in hepatitis B patients with cirrhosis.

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Wu, Hao; Yan, Shiping; Wang, Guangchuan; Cui, Shaobo; Zhang, Chunqing; Zhu, Qiang

2015-01-01

At present, there is no perfect noninvasive method to assess portal hypertension and esophageal varices. Early predicting esophageal varices can provide evidence for managing cirrhotic patients. We aimed to further investigate von Willebrand factor (vWF) as a noninvasive predictor of portal hypertension, especially of esophageal varices. A total of 60 hepatitis B patients with cirrhosis and 45 healthy subjects were enrolled in this study. Levels of six markers were examined. All patients underwent hepatic venous pressure gradient (HVPG) and esophagogastroduodenoscopy. We evaluated the performance of six factors for diagnosis of portal hypertension and esophageal varices. The vWF levels in liver tissues were observed by immunohistochemistry. Correlations between the level of vWF in liver tissues and HVPG and between levels of vWF in tissues and plasma were examined. Cutoff values of plasma vWF (1510.5 mU/mL and 1701 mU/mL) showed high positive predictive value (PPV, 90.2% and 87.5%) in predicting clinically significant portal hypertension and severe portal hypertension. Cutoff values of vWF (1414 mU/ml and 1990 mU/mL, PPV 90.3% and 86.3%, respectively) were provided to detect the presence and degree of esophageal varices. Linear correlations were observed between levels of vWF in liver tissues and HVPG (r(2) = 0.552, p portal hypertension and esophageal varices in hepatitis B patients with cirrhosis. Increased levels of vWF in liver tissues may induce the elevated plasma vWF levels, but molecular mechanism is needed for further study.

The important role of von Willebrand factor in platelet-derived FVIII gene therapy for murine hemophilia A in the presence of inhibitory antibodies.

Science.gov (United States)

Shi, Q; Schroeder, J A; Kuether, E L; Montgomery, R R

2015-07-01

Our previous studies have demonstrated that targeting FVIII expression to platelets results in FVIII storage together with von Willebrand factor (VWF) in platelet α-granules and that platelet-derived FVIII (2bF8) corrects the murine hemophilia A phenotype even in the presence of high-titer anti-FVIII inhibitory antibodies (inhibitors). To explore how VWF has an impact on platelet gene therapy for hemophilia A with inhibitors. 2bF8 transgenic mice in the FVIII(-/-) background (2bF8(tg+/-) F8(-/-) ) with varying VWF phenotypes were used in this study. Animals were analyzed by VWF ELISA, FVIII activity assay, Bethesda assay and tail clip survival test. Only 18% of 2bF8(tg+/-) F8(-/-) VWF(-/-) animals, in which VWF was deficient, survived the tail clip challenge with inhibitor titers of 3-8000 BU mL(-1) . In contrast, 82% of 2bF8(tg+/-) F8(-/-) VWF(+/+) mice, which had normal VWF levels, survived tail clipping with inhibitor titers of 10-50,000 BU mL(-1) . All 2bF8(tg+/-) F8(-/-) VWF(-/-) mice without inhibitors survived tail clipping and no VWF(-/-) F8(-/-) mice survived this challenge. Because VWF is synthesized by endothelial cells and megakaryocytes and is distributed in both plasma and platelets in peripheral blood, we further investigated the effect of each compartment of VWF on platelet-FVIII gene therapy for hemophilia A with inhibitors. In the presence of inhibitors, 42% of animals survived tail clipping in the group with plasma-VWF and 50% survived in the platelet-VWF group. VWF is essential for platelet gene therapy for hemophilia A with inhibitors. Both platelet-VWF and plasma-VWF are required for optimal platelet-derived FVIII gene therapy for hemophilia A in the presence of inhibitors. © 2015 International Society on Thrombosis and Haemostasis.

HTML5 e as possibilidades narrativas jornalísticas na infografia multimídia

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Walter Teixeira Lima Junior

2015-12-01

Full Text Available O artigo propõe o estudo comparativo dos infográficos multimídia produzidos pelos sites Clarín.com, da Argentina e Folha.com, do Brasil. A pesquisa tem como objetivo verificar e analisar como esses dois importantes veículos de comunicação online da América Latina têm utilizado a tecnologia HTML5 e suas possibilidades interativas na narrativa jornalística. Para tanto, a análise vai se ater à infografia multimídia, que tem passado por profundas mudanças tecnológicas, alterando o formato e o conteúdo da notícia. Para abordar as possibilidades narrativas das tecnologias Flash e HTLM5 na produção de infográficos interativos, o trabalho compara as seções Infográficos, veiculada pela Folha.com, e Especiales Multimedia, do Clarín.com. O estudo, quantitativo e qualitativo, verificou quais recursos narrativos e informativos, ferramentas e tecnologias de linguagem de programação para Internet foram utilizados pelos dois meios de comunicação, com base no modelo de análise proposto por Alberto Cairo no livro Infografia 2.0.

Hemorrhoids screening and treatment prior to LVAD: is it a necessity?

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Skouri, Hadi; Shurrab, Mohammed; Zahnan, Jad; Deeba, Samer; Sfeir, Pierre; Gharzuddin, Walid; Haj-Yahia, Saleem

2016-04-12

Continuous-flow left ventricle assist devices (CF-LVADs) has become an essential modality in the management of stage D heart failure (HF) with significant improvement in survival and quality of life. Due to the durability of such devices and long term support complications such as bleeding and aortic insufficiency has emerged. Bleeding accounts for more than 20 % with the majority being from the gastrointestinal tract. The increase of bleeding tendency are mainly attributed to the loss of large von Willebrand's Factor (vWF) multimers due to shear stress with the chronic intake of anticoagulants. We are reporting two cases of patients with Stage D HF and history of hemorrhoids presenting for LVAD implantation. Many efforts that decrease bleeding related to CF-LVADs will be discussed with focus on hemorrhoids.

Molecular cloning of the human gene for von Willebrand factor and identification of the transcription initiation site

International Nuclear Information System (INIS)

Collins, C.J.; Underdahl, J.P.; Levene, R.B.; Ravera, C.P.; Morin, M.J.; Dombalagian, M.J.; Ricca, G.; Livingston, D.M.; Lynch, D.C.

1987-01-01

A series of overlapping cosmid genomic clones have been isolated that contain the entire coding unit of the human gene for van Willebrand factor (vWf), a major component of the hemostatic system. The cloned segments span ≅ 175 kilobases of human DNA sequence, and hybridization analysis suggest that the vWf coding unit is ≅150 kilobases in length. Within one of these clones, the vWF transcription initiation site has been mapped and a portion of the vWf promoter region has been sequenced, revealing a typical TATA box, a downstream CCAAT box, and a perfect downstream repeat of the 8 base pairs containing the transcription start site. Sequencing of a segment of another genomic clone has revealed the vWF translation termination codon. Where tested, comparative restriction analysis of cloned and chromosomal DNA segments strongly suggests that no major alterations occurred during cloning and that there is only one complete copy of the vWf gene in the human haploid genome. Similar analyses of DNA from vWf-producing endothelial cells and nonexpressing leukocytes suggest that vWf gene expression is not accompanied by gross genomic rearrangements. In addition, there is significant homology of C-terminal coding sequences among the vWf genes of several vertebrate species

Nicolas Guichon, Langues et TICE. Méthodologie de conception multimédia

OpenAIRE

Frost, Dan

2014-01-01

Nicolas Guichon est enseignant-chercheur en anglais et en didactique des langues au centre de langues de l’université Lumière (Lyon 2). Il est concepteur du logiciel Virtual Cabinet, responsable de l’enseignement TICE du master « Didactique des langues et TICE » et membre de l’équipe Plurilinguisme et multimédia (ENS de Lyon). Cet ouvrage est le fruit de son expérience dans le domaine des recherches, du développement et de l’enseignement dans l’univers des TICE et de l’apprentissage des langu...

Exercise-induced shear stress is associated with changes in plasma von Willebrand factor in older humans.

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Gonzales, Joaquin U; Thistlethwaite, John R; Thompson, Benjamin C; Scheuermann, Barry W

2009-07-01

Shear stress is the frictional force of blood against the endothelium, a stimulus for endothelial activation and the release of von Willebrand factor (vWF). This study tested the hypothesis that the increase in shear stress associated with exercise correlates with plasma vWF. Young (n = 14, 25.7 +/- 5.4 years) and older (n = 13, 65.6 +/- 10.7 years) individuals participated in 30 min of dynamic handgrip exercise at a moderate intensity. Brachial artery diameter and blood flow were measured using ultrasound Doppler and blood samples were collected before, immediately after, and following 30 min of recovery from exercise with plasma levels of vWF. Plasma levels of vWF increased (P exercise. The change in plasma vWF was linearly correlated with the increase in shear stress during exercise in older individuals (post-exercise: r = 0.78, 30 min recovery: r = 0.77, P < 0.01), but no association was found in the young individuals. These changes in plasma levels of vWF in humans suggest that aging influences endothelial activation and hemostasis.

Von Willebrand Factor as a Novel Player in Valvular Heart Disease: From Bench to Valve Replacement.

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Gragnano, Felice; Crisci, Mario; Bigazzi, Maurizio Cappelli; Bianchi, Renatomaria; Sperlongano, Simona; Natale, Francesco; Fimiani, Fabio; Concilio, Claudia; Cesaro, Arturo; Pariggiano, Ivana; Diana, Vincenzo; Limongelli, Giuseppe; Cirillo, Plinio; Russo, Mariagiovanna; Golia, Enrica; Calabrò, Paolo

2018-02-01

von Willebrand Factor (vWF) is a well-known mediator of hemostasis and vascular inflammation. Its dynamic modulation in the bloodstream, according to hemodynamic conditions, makes it an appealing biomarker in patients with valvular heart disease (VHD). Recent studies highlight the close connection between vWF and VHD, with possible implications in the pathogenesis of VHD, promoting valve aging and calcification or favoring the development of infective endocarditis. Moreover, vWF has been recently proposed as a new diagnostic and prognostic tool in patients with valve stenosis or regurgitation, showing a strict correlation with severity of valve disease, outcome, and bleeding (Heyde syndrome). A novel role for vWF is also emerging in patients undergoing percutaneous or surgical valve repair/replacement to select and stratify patients, evaluate periprocedural bleeding risk, and detect procedural complications. We also report our single-center experience, suggesting, for the first time, possible clinical implications for vWF in percutaneous mitral valve repair (MitraClip). This review summarizes recent advances in the role of vWF in VHD with an updated overview going from bench to operating room.

Cloning of the cDNA for murine von Willebrand factor and identification of orthologous genes reveals the extent of conservation among diverse species.

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Chitta, Mohan S; Duhé, Roy J; Kermode, John C

2007-05-01

Interaction of von Willebrand factor (VWF) with circulating platelets promotes hemostasis when a blood vessel is injured. The A1 domain of VWF is responsible for the initial interaction with platelets and is well conserved among species. Knowledge of the cDNA and genomic DNA sequences for human VWF allowed us to predict the cDNA sequence for murine VWF in silico and amplify its entire coding region by RT-PCR. The murine VWF cDNA has an open reading frame of 8,442 bp, encoding a protein of 2,813 amino acid residues with 83% identity to human pre-pro-VWF. The same strategy was used to predict in silico the cDNA sequence for the ortholog of VWF in a further six species. Many of these predictions diverged substantially from the putative Reference Sequences derived by ab initio methods. Our predicted sequences indicated that the VWF gene has a conserved structure of 52 exons in all seven mammalian species examined, as well as in the chicken. There is a minor structural variation in the pufferfish Takifugu rubripes insofar as the VWF gene in this species has 53 exons. Comparison of the translated amino acid sequences also revealed a high degree of conservation. In particular, the cysteine residues are conserved precisely throughout both the pro-peptide and the mature VWF sequence in all species, with a minor exception in the pufferfish VWF ortholog where two adjacent cysteine residues are omitted. The marked conservation of cysteine residues emphasizes the importance of the intricate pattern of disulfide bonds in governing the structure of pro-VWF and regulating the function of the mature VWF protein. It should also be emphasized that many of the conserved features of the VWF gene and protein were obscured when the comparison among species was based on the putative Reference Sequences instead of our predicted cDNA sequences.

Lei da gravitação universal e os satélites: uma abordagem histórico-temática usando multimídia

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Elvis Vilela Rodrigues

2012-01-01

Full Text Available Examina-se, neste artigo, o desenvolvimento de aulas de Física em que, usando-se uma multimídia, a Lei da Gravitação Universal é abordada de forma contextualizada a partir da História da Ciência e de um tema atual (os satélites. O objetivo foi examinar como estudantes de Ensino Médio aceitam e se envolvem nesse estudo. Usando uma abordagem metodológica qualitativa, a multimídia apresenta o que são e como funcionam os satélites artificiais, trazendo uma narrativa histórica desde as ideias de movimento do sistema planetário de Ptolomeu até as de Isaac Newton sobre o movimento dos corpos, culminando na Lei da Gravitação Universal. Entrevistas, observações de sala de aula e documentos produzidos pelos estudantes mostram que as imagens, os filmes e os textos contidos na multimídia enriquecem, de modo significativo, o conteúdo, facilitando o entendimento de conceitos da Física. A contextualização histórico-temática, por sua vez, produz maior envolvimento dos alunos no estudo da Física.

Differential effects of endurance training and weight loss on plasma adiponectin multimers and adipose tissue macrophages in younger, moderately overweight men

DEFF Research Database (Denmark)

Auerbach, Pernille; Nordby, Pernille; Bendtsen, Line Quist

2013-01-01

in obese subjects which may be due to modulations of inflammatory pathways. In this randomized clinical trial we investigated the separate effects of endurance training-induced weight loss, diet-induced weight loss and endurance training per se (without weight loss) on plasma adiponectin multimer...... composition (Western blotting) and adipose tissue macrophage content (immunohistochemistry) in young, moderately overweight men. Weight loss and endurance training per se decreased whole body fat percentage in an additive manner. No intervention-induced changes were observed for plasma total adiponectin....... Surprisingly, endurance training, irrespectively of any associated weight loss, shifted the adiponectin multimer distribution towards a lower molecular weight (21% decrease in HMW/LMW, P=0.015) whereas diet-induced weight loss shifted the distribution towards a higher molecular weight (42% increase in HMW...

Unconjugated Bilirubin Inhibits Proteolytic Cleavage of von Willebrand Factor by ADAMTS13 Protease

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Lu, Rui-Nan; Yang, Shangbin; Wu, Haifeng M.; Zheng, X. Long

2015-01-01

Summary Background Bilirubin is a yellow breakdown product of heme catabolism. Increased serum levels of unconjugated bilirubin are conditions commonly seen in premature neonates and adults with acute hemolysis including thrombotic microangiopathy. Previous studies have shown that unconjugated bilirubin lowers plasma ADAMTS13 activity, but the mechanism is not fully understood. Objectives The study is to determine whether unconjugated bilirubin directly inhibits the cleavage of von Willebrand factor (VWF) and its analogs by ADAMTS13. Methods Fluorogenic, SELDI-TOF mass spectrometric assay, and Western blotting analyses were employed to address this question. Results Unconjugated bilirubin inhibits the cleavage of F485-rVWF73-H, D633-rVWF73-H, and GST-rVWF71-11K by ADAMTS13 in a concentration-dependent manner with a half-maximal inhibitory concentration (IC50) of ~13 μM, ~70 μM, and ~17 μM, respectively. Unconjugated bilirubin also dose-dependently inhibits the cleavage of multimeric VWF by ADAMTS13 under denaturing conditions. The inhibitory activity of bilirubin on the cleavage of D633-rVWF73-H and multimeric VWF, but not F485-rVWF73-H, was eliminated after incubation with bilirubin oxidase that converts bilirubin to biliverdin. Furthermore, plasma ADAMTS13 activity in patients with hyperbilirubinemia is lower prior to than after treatment with bilirubin oxidase. Conclusions unconjugated bilirubin directly inhibits ADAMTS13’s ability to cleave both peptidyl and native VWF substrates in addition to its interference with certain fluorogenic assays. Our findings may help proper interpretation of ADAMTS13 results under pathological conditions. Whether elevated serum unconjugated bilirubin has an adverse effect in vivo remains to be determined in our future study. PMID:25782102

Evaluation of von Willebrand factor during pregnancy, lactation and oestrous cycle in bitches affected and unaffected by von Willebrand disease.

Science.gov (United States)

Mattoso, C R S; Takahira, R K; Beier, S L; Araujo, J P; Corrente, J E

2013-06-01

Plasmatic concentrations of von Willebrand Factor (vWF) increase during pregnancy in humans and dogs; however the mechanism of such increase is still not well defined. The aims of this study were: (i) to evaluate changes in vWF concentration during pregnancy and during the subsequent oestrous cycle in bitches affected and unaffected by von Willebrand Disease (vWD); (ii) to correlate the vWF levels and cortisol levels in both groups. Seven vWD affected (GI) and nine unaffected (GII) bitches were used. The animals were assessed during pregnancy, parturition, lactation and non-gestational oestrous cycle in 11 moments (Pregnancy 1, Pregnancy 2, Parturition, Lactation 1, Lactation 2, Lactation 3, Anestrus, Proestrus, Oestrus, Diestrus 1, and Diestrus 2). The following tests were performed; measurement of von Willebrand factor antigen (vWF:Ag), albumin and cortisol. In both groups, vWF concentration remained stable during the non-gestational oestrous cycle, but increased during pregnancy, with the highest value observed at parturition. Increases of 70% and 124% in vWF were seen in GI and GII, respectively, compared to anestrus. No correlation was found between vWF and cortisol. Values of vWF:Ag changed during pregnancy, with a peak at parturition, both in vWD affected and unaffected animals. Values of vWF were not altered in the different phases of the oestrous cycle following pregnancy in both groups. Evaluation of vWF during pregnancy can cause false negative results for vWD, but assessment can be performed at any point in the oestrous cycle of non-pregnant bitches. © 2012 Blackwell Verlag GmbH.

Automated Analysis of Flow Cytometry Data to Reduce Inter-Lab Variation in the Detection of Major Histocompatibility Complex Multimer-Binding T Cells

DEFF Research Database (Denmark)

Pedersen, Natasja Wulff; Chandran, P. Anoop; Qian, Yu

2017-01-01

Manual analysis of flow cytometry data and subjective gate-border decisions taken by individuals continue to be a source of variation in the assessment of antigen-specific T cells when comparing data across laboratories, and also over time in individual labs. Therefore, strategies to provide...... automated analysis of major histocompatibility complex (MHC) multimer-binding T cells represent an attractive solution to decrease subjectivity and technical variation. The challenge of using an automated analysis approach is that MHC multimer-binding T cell populations are often rare and therefore...... laboratories. We used three different methods, FLOw Clustering without K (FLOCK), Scalable Weighted Iterative Flow-clustering Technique (SWIFT), and ReFlow to analyze flow cytometry data files from 28 laboratories. Each laboratory screened for antigen-responsive T cell populations with frequency ranging from 0...

Insulin resistance is accompanied by increased von Willebrand factor levels in nondiabetic women: a study of offspring of type 2 diabetic subjects compared to offspring of nondiabetic subjects

DEFF Research Database (Denmark)

Foss, Anne-Catherine; Vestbo, Else; Frøland, Anders

2002-01-01

OBJECTIVES: To examine whether levels of von Willebrand factor (vWF), fibrinogen and fibronectin are related to a parental history of type 2 diabetes and to determine possible explanatory factors for high versus low vWF and fibrinogen. DESIGN: Cross-sectional study. SUBJECTS, MAIN OUTCOME MEASURE...

Site-specific deletions of chromosomally located DNA segments with the multimer resolution system of broad-host-range plasmid RP4

DEFF Research Database (Denmark)

Sternberg, Claus; Eberl, Leo; Sanchezromero, Juan M.

1995-01-01

The multimer resolution system (mrs) of the broad-host-range plasmid RP4 has been exploited to develop a general method that permits the precise excision of chromosomal segments in a variety of gram-negative bacteria. The procedure is based on the site-specific recombination between two directly ...

Evidence that the rabbit proton-peptide co-transporter PepT1 is a multimer when expressed in Xenopus laevis oocytes.

Science.gov (United States)

Panitsas, Konstantinos-E; Boyd, C A R; Meredith, David

2006-04-01

To test whether the rabbit proton-coupled peptide transporter PepT1 is a multimer, we have employed a combination of transport assays, luminometry and site-directed mutagenesis. A functional epitope-tagged PepT1 construct (PepT1-FLAG) was co-expressed in Xenopus laevis oocytes with a non-functional but normally trafficked mutant form of the same transporter (W294F-PepT1). The amount of PepT1-FLAG cRNA injected into the oocytes was kept constant, while the amount of W294F-PepT1 cRNA was increased over the mole fraction range of 0 to 1. The uptake of [(3)H]-D: -Phe-L: -Gln into the oocytes was measured at pH(out) 5.5, and the surface expression of PepT1-FLAG was quantified by luminometry. As the mole fraction of injected W294F-PepT1 increased, the uptake of D: -Phe-L: -Gln decreased. This occurred despite the surface expression of PepT1-FLAG remaining constant, and so we can conclude that PepT1 must be a multimer. Assuming that PepT1 acts as a homomultimer, the best fit for the modelling suggests that PepT1 could be a tetramer, with a minimum requirement of two functional subunits in each protein complex. Western blotting also showed the presence of higher-order complexes of PepT1-FLAG in oocyte membranes. It should be noted that we cannot formally exclude the possibility that PepT1 interacts with unidentified Xenopus protein(s). The finding that PepT1 is a multimer has important implications for the molecular modelling of this protein.

Inhibition of Hb Binding to GP1bα Abrogates Hb-Mediated Thrombus Formation on Immobilized VWF and Collagen under Physiological Shear Stress.

Science.gov (United States)

Annarapu, Gowtham K; Singhal, Rashi; Peng, Yuandong; Guchhait, Prasenjit

2016-01-01

Reports including our own describe that intravascular hemolysis increases the risk of thrombosis in hemolytic disorders. Our recent study shows that plasma Hb concentrations correlate directly with platelet activation in patients with paroxysmal nocturnal hemoglobinuria (PNH). The binding of Hb to glycoprotein1bα (GP1bα) increases platelet activation. A peptide AA1-50, designed from N-terminal amino acid sequence of GP1bα significantly inhibits the Hb binding to GP1bα as well as Hb-induced platelet activation. This study further examined if the Hb-mediated platelet activation plays any significant role in thrombus formation on subendothelium matrix under physiological flow shear stresses and the inhibition of Hb-platelet interaction can abrogate the above effects of Hb. Study performed thrombus formation assay in vitro by perfusing whole blood over immobilized VWF or collagen type I in presence of Hb under shear stresses simulating arterial or venous flow. The Hb concentrations ranging from 5 to 10 μM, commonly observed level in plasma of the hemolytic patients including PNH, dose-dependently increased thrombus formation on immobilized VWF under higher shear stress of 25 dyne/cm2, but not at 5 dyne/cm2. The above Hb concentrations also increased thrombus formation on immobilized collagen under both shear stresses of 5 and 25 dyne/cm2. The peptide AA1-50 abrogated invariably the above effects of Hb on thrombus formation. This study therefore indicates that the Hb-induced platelet activation plays a crucial role in thrombus formation on immobilized VWF or collagen under physiological flow shear stresses. Thus suggesting a probable role of this mechanism in facilitating thrombosis under hemolytic conditions.

Association of von Willebrand factor blood levels with exercise hypertension.

Science.gov (United States)

Nikolic, Sonja B; Adams, Murray J; Otahal, Petr; Edwards, Lindsay M; Sharman, James E

2015-05-01

A hypertensive response to moderate intensity exercise (HRE) is associated with increased cardiovascular risk. The mechanisms of an HRE are unclear, although previous studies suggest this may be due to haemostatic and/or haemodynamic factors. We investigated the relationships between an HRE with haemostatic and hemodynamic indices. Sixty-four participants (57 ± 10 years, 71 % male) with indication for exercise stress testing underwent cardiovascular assessment at rest and during moderate intensity exercise, from which 20 participants developed an HRE (defined as moderate exercise systolic BP ≥ 170 mmHg/men and ≥ 160 mmHg/women). Rest, exercise and post-exercise blood samples were analysed for haemostatic markers, including von Willebrand factor (vWf), and haemodynamic measures of brachial and central blood pressure (BP), aortic stiffness and systemic vascular resistance index (SVRi). HRE participants had higher rest vWf compared with normotensive response to exercise (NRE) participants (1,927 mU/mL, 95 % CI 1,240-2,615, vs. 1,129 mU/mL, 95 % CI 871-1,386; p = 0.016). vWf levels significantly decreased from rest to post-exercise in HRE participants (p = 0.005), whereas vWf levels significantly increased from rest to exercise in NRE participants (p = 0.030). HRE participants also had increased triglycerides, rest BP, aortic stiffness and exercise SVRi (p HRE at moderate intensity.

Utilização de uma ferramenta multimídia para identificação de Artrópodes: avaliação de estudantes do Ensino Fundamental

Directory of Open Access Journals (Sweden)

Tiago José Benedito Eugênio

2012-01-01

Full Text Available No presente artigo apresentamos um modelo de montagem e produção de um CD-ROM com recursos para identificação de 22 animais, que disponibiliza, para o aluno, uma chave multimídia para identificação de artrópodes. Tratamos de avaliar esta chave multimídia como ferramenta didática em quatro turmas (sétimo, oitavo e nono ano do Ensino Fundamental de uma escola privada do município de Parnamirim, RN. A avaliação foi dividida em duas etapas: avaliação através de questionário imediatamente após o contato com a chave multimídia, e comparação entre as notas obtidas em exames por escrito de alunos que tiveram e não tiveram contato com a ferramenta didática. Ao todo, 89 alunos participaram das duas etapas da avaliação. Constatamos, de forma geral, uma avaliação positiva e um desempenho significativamente maior dos alunos que interagiram com a ferramenta didática no exame por escrito.

A BENCHMARKING ANALYSIS FOR FIVE RADIONUCLIDE VADOSE ZONE MODELS (CHAIN, MULTIMED_DP, FECTUZ, HYDRUS, AND CHAIN 2D) IN SOIL SCREENING LEVEL CALCULATIONS

Science.gov (United States)

Five radionuclide vadose zone models with different degrees of complexity (CHAIN, MULTIMED_DP, FECTUZ, HYDRUS, and CHAIN 2D) were selected for use in soil screening level (SSL) calculations. A benchmarking analysis between the models was conducted for a radionuclide (99Tc) rele...

Activation of pathways involved in HUVEC apoptosis and proliferation. Sex hormones agonist related. Effect of hormones on von Willebrand factor and ADAMTS 13 release

OpenAIRE

Powazniak, Yanina

2008-01-01

El VWF es una glicoproteína adhesiva, sintetizada en las CE y megacariocitos. Se sintetiza en forma monomérica, luego se organiza en dímeros y se multimeriza. El VWF media la adhesión de plaquetas al subendotelio vascular dañado y lel transporte del factor FVIII. La ADAMTS13, proteasa que cliva al VWF, pertenece a la familia de metaloproteasas ADAMTS, llamadas así por la combinación característica de una desintegrina y una metaloproteasa con motivos trombospondina tipo 1. La ADAMTS13 es sinte...

Establishment and characterization of a new and stable collagen-binding assay for the assessment of von Willebrand factor activity

Science.gov (United States)

Ni, Y; Nesrallah, J; Agnew, M; Geske, F J; Favaloro, E J

2013-01-01

Introduction Laboratory diagnosis of von Willebrand disease (VWD) requires determination of both von Willebrand factor (VWF) protein levels and activity. Current VWF activity tests include the ristocetin cofactor assay and the collagen-binding assay (VWF:CB). The goal of this investigation is to characterize a new collagen-binding assay and to determine its effectiveness in identifying VWD. Methods Analytical studies were carried out to characterize the performance of a new VWF:CB ELISA. Additionally, samples from a normal population were tested as were well-characterized type 1 and type 2 VWD samples. Results Repeatability and within-laboratory precision studies resulted in coefficients of variation (CVs) of ≤11%. A linear range of 1–354% (0.01–3.54 IU/mL) was determined, along with a limit of detection and a lower limit of quantitation of 1.6% and 4.0% (0.016 and 0.04 IU/mL), respectively. Samples tested from apparently healthy individuals resulted in a normal range of 54–217% (0.54–2.17 IU/mL). Known VWD type 1 and type 2 samples were also analyzed by the ELISA, with 99% of samples having VWF:CB below the normal reference range and an estimated 96% sensitivity and 87% specificity using a VWF collagen-binding/antigen cutoff ratio of 0.50. Conclusion This new VWF:CB ELISA provides an accurate measure of collagen-binding activity that aids in the diagnosis and differentiation of type 1 from type 2 VWD. PMID:23107512

Differential effects of the loss of intrachain- versus interchain-disulfide bonds in the cystine-knot domain of von Willebrand factor on the clinical phenotype of von Willebrand disease

NARCIS (Netherlands)

Tjernberg, Pernilla; Vos, Hans L.; Spaargaren-van Riel, Caroline C.; Luken, Brenda M.; Voorberg, Jan; Bertina, Rogier M.; Eikenboom, Jeroen C. J.

2006-01-01

Von Willebrand factor (VWF) contains a large number of cysteine residues, which all form disulfide bonds. Mutations of cysteines located in the cystine-knot (CK) domain of VWF have been identified in both qualitative type 2A (IID) and quantitative type 3 von Willebrand disease (VWD). Our objective

CMV-specific T cell isolation from G-CSF mobilized peripheral blood: depletion of myeloid progenitors eliminates non-specific binding of MHC-multimers.

Science.gov (United States)

Beloki, Lorea; Ciaurriz, Miriam; Mansilla, Cristina; Zabalza, Amaya; Perez-Valderrama, Estela; Samuel, Edward R; Lowdell, Mark W; Ramirez, Natalia; Olavarria, Eduardo

2014-11-19

Cytomegalovirus (CMV)-specific T cell infusion to immunocompromised patients following allogeneic Hematopoietic Stem Cell Transplantation (allo-HSCT) is able to induce a successful anti-viral response. These cells have classically been manufactured from steady-state apheresis samples collected from the donor in an additional harvest prior to G-CSF mobilization, treatment that induces hematopoietic stem cell (HSC) mobilization to the periphery. However, two closely-timed cellular collections are not usually available in the unrelated donor setting, which limits the accessibility of anti-viral cells for adoptive immunotherapy. CMV-specific cytotoxic T cell (CTL) manufacture from the same G-CSF mobilized donor stem cell harvest offers great regulatory advantages, but the isolation using MHC-multimers is hampered by the high non-specific binding to myeloid progenitors, which reduces the purity of the cellular product. In the present study we describe an easy and fast method based on plastic adherence to remove myeloid cell subsets from 11 G-CSF mobilized donor samples. CMV-specific CTLs were isolated from the non-adherent fraction using pentamers and purity and yield of the process were compared to products obtained from unmanipulated samples. After the elimination of unwanted cell subtypes, non-specific binding of pentamers was notably reduced. Accordingly, following the isolation process the purity of the obtained cellular product was significantly improved. G-CSF mobilized leukapheresis samples can successfully be used to isolate antigen-specific T cells with MHC-multimers to be adoptively transferred following allo-HSCT, widening the accessibility of this therapy in the unrelated donor setting. The combination of the clinically translatable plastic adherence process to the antigen-specific cell isolation using MHC-multimers improves the quality of the therapeutic cellular product, thereby reducing the clinical negative effects associated with undesired

Von Willebrand factor indicates bacterial translocation, inflammation, and procoagulant imbalance and predicts complications independently of portal hypertension severity.

Science.gov (United States)

Mandorfer, M; Schwabl, P; Paternostro, R; Pomej, K; Bauer, D; Thaler, J; Ay, C; Quehenberger, P; Fritzer-Szekeres, M; Peck-Radosavljevic, M; Trauner, M; Reiberger, T; Ferlitsch, A

2018-04-01

Elevated plasma von Willebrand factor antigen (vWF) has been shown to indicate the presence of clinically significant portal hypertension, and thus, predicts the development of clinical events in patients with cirrhosis. To investigate the impact of bacterial translocation and inflammation on vWF, as well as the association between vWF and procoagulant imbalance. Moreover, we assessed whether vWF predicts complications of cirrhosis, independent of the severity of portal hypertension. Our study population comprised 225 patients with hepatic venous pressure gradient (HVPG) ≥ 10 mm Hg without active bacterial infections or hepatocellular carcinoma. vWF correlated with markers of bacterial translocation (lipopolysaccharide-binding protein [LBP; ρ = 0.201; P = 0.021]), inflammation (interleukin 6 [IL-6; ρ = 0.426; P protein [CRP; ρ = 0.249; P protein C ratio; ρ = 0.507; P model for transplant-free mortality. Finally, the independent prognostic value of vWF/CRP groups for mortality was confirmed by competing risk analysis. Our results demonstrate that vWF is not only a marker of portal hypertension but also independently linked to bacterial translocation, inflammation and procoagulant imbalance, which might explain its HVPG-independent association with most clinical events. Prognostic groups based on vWF/CRP efficiently discriminate between patients with a poor 5-year survival and patients with a favourable prognosis. © 2018 John Wiley & Sons Ltd.

Large-scale detection of antigen-specific T cells using peptide-MHC-I multimers labeled with DNA barcodes

DEFF Research Database (Denmark)

Bentzen, Amalie Kai; Marquard, Andrea Marion; Lyngaa, Rikke Birgitte

2016-01-01

-major histocompatibility complex (MHC) multimers labeled with individual DNA barcodes to screen >1,000 peptide specificities in a single sample, and detect low-frequency CD8 T cells specific for virus- or cancer-restricted antigens. When analyzing T-cell recognition of shared melanoma antigens before and after adoptive...... cell therapy in melanoma patients, we observe a greater number of melanoma-specific T-cell populations compared with cytometry-based approaches. Furthermore, we detect neoepitope-specific T cells in tumor-infiltrating lymphocytes and peripheral blood from patients with non-small cell lung cancer...

Data analysis as a source of variability of the HLA-peptide multimer assay

DEFF Research Database (Denmark)

Gouttefangeas, Cécile; Chan, Cliburn; Attig, Sebastian

2015-01-01

by laboratories performing ex vivo T cell immune monitoring. In particular, analysis currently relies on a manual, step-by-step strategy employing serial gating decisions based on visual inspection of one- or two-dimensional plots. It is therefore operator dependent and subjective. In the context of continuing......Multiparameter flow cytometry is an indispensable method for assessing antigen-specific T cells in basic research and cancer immunotherapy. Proficiency panels have shown that cell sample processing, test protocols and data analysis may all contribute to the variability of the results obtained...... efforts to support inter-laboratory T cell assay harmonization, the CIMT Immunoguiding Program organized its third proficiency panel dedicated to the detection of antigen-specific CD8(+) T cells by HLA-peptide multimer staining. We first assessed the contribution of manual data analysis to the variability...

No evidence for a direct effect of von Willebrand factor's ABH blood group antigens on von Willebrand factor clearance

NARCIS (Netherlands)

Groeneveld, D J; van Bekkum, T; Cheung, K L; Dirven, R J; Castaman, G; Reitsma, P H; van Vlijmen, B; Eikenboom, J

BACKGROUND: One of the major determinants of von Willebrand factor (VWF) plasma levels is ABO blood group status, and individuals with blood group O have ~ 25% lower plasma levels. The exact mechanism behind this relationship remains unknown, although effects on clearance have been postulated.

La eficiencia teórica y metodológica de los diseños multimétodo

Directory of Open Access Journals (Sweden)

JOAN M. VERD

2008-01-01

Full Text Available En los últimos años, el ya viejo debate en torno a la articulación metodológica se ha centrado con fuerza en las implicaciones de las investigaciones multimétodo o basadas en la mezcla de métodos (métodos mixtos. En este contexto se ha reflexionado con cierta profundidad, especialmente en el ámbito anglosajón, respecto a las ventajas metodológicas que aportan este tipo de diseños, aunque bastante menos respecto a los beneficios que se aportan a la reflexión teórica. Partiendo de la premisa de que este tipo de diseño no debe entenderse como una vía de escape a la realidad multiparadigmática de la investigación sociológica, el artículo defiende que el diseño multimétodo es más eficiente teórica y metodológicamente que los diseños exclusivamente cuantitativos o cualitativos. Utilizando la terminología de Creswell, se argumenta que la eficiencia metodológica se consigue especialmente con los diseños de carácter secuencial, mientras que la eficiencia teórica se consigue especialmente con los diseños de carácter concurrente, sobre todo en su vertiente anidada. Estos argumentos se refuerzan con ejemplos de una investigación que los dos autores han terminado recientemente, centrada en la realidad juvenil catalana.

One-pot preparation of conducting composite containing abundant amino groups on electrode surface for electrochemical detection of von willebrand factor

Science.gov (United States)

Wang, Wen; Ma, Chao; Li, Yi; Liu, Baihui; Tan, Liang

2018-03-01

A one-pot protocol based on cyclic voltammetric scan was employed to prepare new conducting composite that was abundant in amino groups. The scanning electron microscope, atomic force microscope, X-ray photoelectron spectroscopy and infrared spectrum characterization demonstrate that poly(azure A), gold nanoparticles, chitosan and cysteine were immobilized simultaneously on glassy carbon electrode surface. Von Willebrand factor (vWF) antibody (Ab) was subsequently assembled by using glutaraldehyde to construct the Ab/composite-modified electrode. The capture of vWF could inhibit the charge transfer between the ferri-/ferrocyanide probe and the electrode and exert the negative effect on the electrochemical response of the dye polymer in the conducting composite due to the strong steric hindrance effect. The DPV peak current change before and after the immunoreaction was found to be proportional to the logarithm of the vWF concentration from 0.001 to 100 μg mL-1 with a detection limit of 0.4 ng mL-1. The proposed label-free electrochemical method was employed in the investigation on the release of vWF by oxidation-injured vascular endothelial cells. The experimental results exhibit that the vWF content in growth medium was increased when the oxidation injury of the cells was intensified in the presence of H2O2.

Produção de multimídia e acessibilidade em cursos de aprendizagem a distância

OpenAIRE

Amorim, Joni A.; Silva, Mariana da Rocha C.

2009-01-01

Estudantes online que são surdos podem encontrar diferentes barreiras em cursos baseados na Web incluindo falta de imagens relacionadas ao conteúdo em páginas tomadas por texto. As diferentes barreiras podem diminuir a compreensão para pessoas cuja primeira língua seja a linguagem de sinais ao invés da linguagem escrita, um desafio para pesquisadores e professores interessados em desenvolver conteúdo multimídia. A combinação de texto, imagem, áudio e vídeo foi potencializada devido à convergê...

Exercise-induced shear stress is associated with changes in plasma von Willebrand factor in older humans

OpenAIRE

Gonzales, Joaquin U.; Thistlethwaite, John R.; Thompson, Benjamin C.; Scheuermann, Barry W.

2009-01-01

Shear stress is the frictional force of blood against the endothelium, a stimulus for endothelial activation and the release of von Willebrand factor (vWF). This study tested the hypothesis that the increase in shear stress associated with exercise correlates with plasma vWF. Young (n = 14, 25.7 ± 5.4 y) and older (n = 13, 65.6 ± 10.7 y) individuals participated in 30 min of dynamic handgrip exercise at a moderate intensity. Brachial artery diameter and blood flow were measured using ultrasou...

Storage and regulated secretion of factor VIII in blood outgrowth endothelial cells

NARCIS (Netherlands)

van den Biggelaar, M.; Bouwens, E.A.M.; Kootstra, N.A.; Hebbel, R.P.; Voorberg, J.; Mertens, K.

2009-01-01

Background Gene therapy provides an attractive alternative for protein replacement therapy in hemophilia A patients. Recent studies have shown the potential benefit of directing factor (F)VIII gene delivery to cells that also express its natural carrier protein von Willebrand factor (VWF). In this

Storage and regulated secretion of factor VIII in blood outgrowth endothelial cells

NARCIS (Netherlands)

van den Biggelaar, Maartje; Bouwens, Eveline A. M.; Kootstra, Neeltje A.; Hebbel, Robert P.; Voorberg, Jan; Mertens, Koen

2009-01-01

Gene therapy provides an attractive alternative for protein replacement therapy in hemophilia A patients. Recent studies have shown the potential benefit of directing factor (F)VIII gene delivery to cells that also express its natural carrier protein von Willebrand factor (VWF). In this study, we

Effects on coagulation factor production following primary hepatomitogen-induced direct hyperplasia.

Science.gov (United States)

Tatsumi, Kohei; Ohashi, Kazuo; Taminishi, Sanae; Takagi, Soichi; Utoh, Rie; Yoshioka, Akira; Shima, Midori; Okano, Teruo

2009-11-14

To investigate the molecular mechanisms involved in coagulation factor expression and/or function during direct hyperplasia (DH)-mediated liver regeneration. Direct hyperplasia-mediated liver regeneration was induced in female C57BL/6 mice by administering 1,4-bis[2-(3,5-dichloropyridyloxy)] benzene (TCPOBOP), a representative hepatomitogen. Mice were weighed and sacrificed at various time points [Day 0 (D0: prior to injection), 3 h, D1, D2, D3, and D10] after TCPOBOP administration to obtain liver and blood samples. Using the RNA samples extracted from the liver, a comprehensive analysis was performed on the hepatic gene expression profiling of coagulation-related factors by real-time RT-PCR (fibrinogen, prothrombin, factors V, VII, VIII, IX, X, XI, XII, XIIIbeta, plasminogen, antithrombin, protein C, protein S, ADAMTS13, and VWF). The corresponding plasma levels of coagulation factors (fibrinogen, prothrombin, factors V, VII, VIII, IX, X, XI, XII, XIII, and VWF) were also analyzed and compared with their mRNA levels. Gavage administration of TCPOBOP (3 mg/kg body weight) resulted in a marked and gradual increase in the weight of the mouse livers relative to the total body weight to 220% by D10 relative to the D0 (control) ratios. At the peak of liver regeneration (D1 and D2), the gene expression levels for most of the coagulation-related factors (fibrinogen, prothrombin, factors V, VII, VIII, IX, XI, XII, XIIIbeta, plasminogen, antithrombin, protein C, ADAMTS13, VWF) were found to be down-regulated in a time-dependent manner, and gradually recovered by D10 to the basal levels. Only mRNA levels of factor X and protein S failed to show any decrease during the regenerative phase. As for the plasma levels, 5 clotting factors (prothrombin, factors VIII, IX, XI, and XII) demonstrated a significant decrease (Pfactors, factor IX and factor XI showed the most dramatic decline in their activities by about 50% at D2 compared to the basal levels, and these reductions in

Effects of coagulation factors and inflammatory cytokines on ...

African Journals Online (AJOL)

Tropical Journal of Pharmaceutical Research April 2016; 15 (4): 827-831. ISSN: 1596-5996 (print); ... fibrinogen (Fg) and von Willebrand factor (vWF) in plasma were analyzed by enzyme-linked ... determined by Western blot analysis. Inflammatory ... Currently, coronary heart disease (CHD) has become one .... membrane.

Testosterone and acute stress are associated with fibrinogen and von Willebrand factor in African men: the SABPA study.

Science.gov (United States)

Malan, Nicolaas T; von Känel, Roland; Schutte, Alta E; Huisman, Hugo W; Schutte, Rudolph; Smith, Wayne; Mels, Carina M; Kruger, Ruan; Meiring, Muriel; van Rooyen, Johannes M; Malan, Leoné

2013-10-12

Low testosterone, acute and chronic stress and hypercoagulation are all associated with hypertension and hypertension-related diseases. The interaction between these factors and future risk for coronary artery disease in Africans has not been fully elucidated. In this study, associations of testosterone, acute cardiovascular and coagulation stress responses with fibrinogen and von Willebrand factor in African and Caucasian men in a South African cohort were investigated. Cardiovascular variables were studied by means of beat-to-beat and ambulatory blood pressure monitoring. Fasting serum-, salivary testosterone and citrate coagulation markers were obtained from venous blood samples. Acute mental stress responses were evoked with the Stroop test. The African group demonstrated a higher cardiovascular risk compared to Caucasian men with elevated blood pressure, low-grade inflammation, chronic hyperglycemia (HbA1c), lower testosterone levels, and elevated von Willebrand factor (VWF) and fibrinogen levels. Blunted testosterone acute mental stress responses were demonstrated in African males. In multiple regression analyses, higher circulating levels of fibrinogen and VWF in Africans were associated with a low T environment (R(2) 0.24-0.28; p≤0.01), but only circulating fibrinogen in Caucasians. Regarding endothelial function, a low testosterone environment and a profile of augmented α-adrenergic acute mental stress responses (diastolic BP, D-dimer and testosterone) were associated with circulating VWF levels in Africans (Adj R(2) 0.24; pstress, salivary testosterone, D-dimer and vascular responses existed in African males in their association with circulating VWF but no interdependence of the independent variables occurred with fibrinogen levels. © 2013.

D-dimer, factor VIII and von Willebrand factor predict a non-dipping pattern of blood pressure in hypertensive patients.

Science.gov (United States)

Agorasti, Athanasia; Trivellas, Theodoros; Mourvati, Efthimia; Papadopoulos, Vasilios; Tsatalas, Konstantinos; Vargemezis, Vasilios; Passadakis, Ploumis

2013-06-01

The aim of this study is to assess whether the haemostatic markers D-dimer, factor VIII (FVIII) and von Willebrand factor (VWF) are predictive of non-dipping status in treated hypertensive patients; so, as easy available laboratory data can predict non-dipping pattern and help with the selection of the patients whom circadian blood pressure should be re-examined. Forty treated hypertensive patients with essential hypertension were included in the study. Twenty-four-hour ambulatory blood pressure monitoring was performed in all patients. Daytime and nocturnal average systolic, diastolic and mean blood pressures were calculated. Patients were characterised as "non-dippers" on the basis of a less than 10 % decline in nocturnal blood pressure (BP); either systolic or diastolic or mean (MAP). D-dimer as marker of fibrinolytic function, FVIII activity and VWF antigen as marker of endothelial dysfunction were measured on plasma. The predictive efficiency was analysed by receiver operating characteristic (ROC) curves. Youden index was used for the estimation of the cut-off points and the associated values for sensitivity and 1-specificity. Plasma levels of D-dimer, FVIII and VWF were significantly higher in non-dippers as compared with dippers, irrespective of the classification used (BP index); all P AUC(ROC) = 0.697, 0.715 and 0.774), FVIII (AUC(ROC) = 0.714, 0.692 and 0.755) and VWF (AUC(ROC) = 0.706, 0.740 and 0.708) in distinguishing non-dipping pattern (systolic, diastolic or mean) in the study population; all P 168 ng/ml (sensitivity/1-specificity for systolic BP non-dippers of 0.789/0.381, for diastolic BP non-dippers 0.923/0.444 and for MAP non-dippers 0.875/0.375). In conclusion, D-dimer has a good predictive value for non-dipping pattern and the decision for the 24-h ambulatory blood pressure re-monitoring among dippers could rely on its values.

Pattern of von Willebrand factor in hypertensive patients in Lagos, Nigeria

Directory of Open Access Journals (Sweden)

Ann Abiola Ogbenna

2018-01-01

Full Text Available Background and Objective: Hypertension alone accounts for 50% of death from stroke. Its ability to induce endothelial dysfunction leads to the release of von Willebrand factor (vWF, a prothrombotic glycoprotein. The increase secretion of vWF may account for increased risk of stroke in hypertensive disorders. This study aimed to determine the vWF:antigen (Ag levels among hypertensives and assess its relationship with blood pressure and occurrence of stroke in hypertensives. Subjects and Methods: The study included 66 hypertensives, 33 with stroke (HS and 33 without stroke (HWS, and 33 controls matched for age and sex. Structured questionnaires were used to obtain biodata and clinical information. Blood pressure was taken after 15 min rest. Four milliliters of blood was collected into 0.1 ml of 3.2% trisodium citrate for vWF:Ag assay and 4 ml into K-ethylenediaminetetraacetic acid anticoagulant bottles for blood grouping and erythrocyte sedimentation rate. Data were analyzed with SPSS version 21. Confidence interval was set at 95%. Results: Mean vWF:Ag levels were significantly higher in hypertensives compared with nonhypertensives (P = 0.005, but no statistically significant difference was observed between HS and HWS (P = 0.874. A positive correlation of vWF with systolic blood pressure was observed (r = 0.335, P = 0.001. Conclusion: Our study suggests that higher systolic blood pressure is associated with higher levels of endothelial activation and release of vWF.

Beneficial Effects of High-Density Lipoproteins on Acquired von Willebrand Syndrome in Aortic Valve Stenosis.

Science.gov (United States)

Gebhard, C; Maafi, F; Stähli, B E; Bonnefoy, A; Gebhard, C E; Nachar, W; de Oliveira Moraes, A Benjamim; Mecteau, M; Mihalache-Avram, T; Lavoie, V; Kernaleguen, A E; Shi, Y; Busseuil, D; Chabot-Blanchet, M; Perrault, L P; Rhainds, D; Rhéaume, E; Tardif, J C

2018-02-01

 Infusions of apolipoprotein A-I (apoA-I), the major protein component of high-density lipoproteins (HDL), result in aortic valve stenosis (AVS) regression in experimental models. Severe AVS can be complicated by acquired von Willebrand syndrome, a haemorrhagic disorder associated with loss of high-molecular-weight von Willebrand factor (vWF) multimers (HMWM), the latter being a consequence of increased shear stress and enhanced vWF-cleaving protease (ADAMTS-13) activity. Although antithrombotic actions of HDL have been described, its effects on ADAMTS-13 and vWF in AVS are unknown.  We assessed ADAMTS-13 activity in plasma derived from a rabbit model of AVS ( n  = 29) as well as in plasma collected from 64 patients with severe AVS (age 65.0 ± 10.4 years, 44 males) undergoing aortic valve replacement (AVR). In both human and rabbit AVS plasma, ADAMTS-13 activity was higher than that in controls ( p  AVS patients had less HMWM than controls (66.3 ± 27.2% vs. 97.2 ± 24.1%, p  AVS rabbits as compared with the placebo group (2.0 ± 0.5 RFU/sec vs. 3.8 ± 0.4 RFU/sec, p  AVS ( r  = -0.3, p  = 0.045).  Our data indicate that HDL levels are associated with reduced ADAMTS-13 activity and increased HMWM. HDL-based therapies may reduce the haematologic abnormalities of the acquired von Willebrand syndrome in AVS. Schattauer GmbH Stuttgart.

ADAMTS13 Gene Mutations in Children with Hemolytic Uremic Syndrome

Science.gov (United States)

Choi, Hyoung Soo; Cheong, Hae Il; Kim, Nam Keun

2011-01-01

We investigated ADAMTS13 activity as well as the ADAMTS13 gene mutation in children with hemolytic uremic syndrome (HUS). Eighteen patients, including 6 diarrhea-negative (D-HUS) and 12 diarrhea-associated HUS (D+HUS) patients, were evaluated. The extent of von Willebrand factor (VWF) degradation was assayed by multimer analysis, and all exons of the ADAMTS13 gene were PCR-amplified using Taq DNA polymerase. The median and range for plasma activity of ADAMTS13 in 6 D-HUS and 12 D+HUS patients were 71.8% (22.8-94.1%) and 84.9% (37.9-119.9%), respectively, which were not statistically significantly different from the control group (86.4%, 34.2-112.3%) (p>0.05). Five ADAMTS13 gene mutations, including 2 novel mutations [1584+2T>A, 3941C>T (S1314L)] and 3 polymorphisms (Q448E, P475S, S903L), were found in 2 D-HUS and one D+HUS patients, which were not associated with deficiency of ADAMTS13 activity. Whether these mutations without reduced ADAMTS13 activity are innocent bystanders or predisposing factors in HUS remains unanswered. PMID:21488199

Réflexions linguistiques et sémiologiques pour une écriture didactique du multimédia de langues Linguistic and "semiologic" reflections to set out a multimedia approach for foreign languages teaching and learning

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Anne-Laure Foucher

1998-06-01

Full Text Available Dans une combinaison originale de domaines souvent envisagés de manière fermée que sont la didactique des langues, la linguistique, la sémiologie et l'ALAO (Apprentissage des Langues Assisté par Ordinateur, nous mettons en avant la nécessité de concevoir l'image multimédia comme un objet composite, lieu véritable d'interactions entre modes iconique, auditif et linguistique. De cette option théorique découle, selon nous, une philosophie qui préside à la conception d'un multimédia pour l'apprentissage des langues. Nous en donnons les grandes lignes sous forme de jalons méthodologiques destinés à une écriture du multimédia en langues.Assuming CALL to need language didactics, assuming didactics to need linguistics and CALL to need minimal " semiologic " reflections, we show how is profitable to adopt a didactic point of view linking linguistic and semiologic aspects in order to examine the contributions to learning of a multimedia approach for foreign languages. To complete these theorical considerations, we propose to set out methodological advice to design a multimedia approach for language learning and teaching.

Application of a molecular diagnostic algorithm for haemophilia A and B using next-generation sequencing of entire F8, F9 and VWF genes.

Science.gov (United States)

Bastida, Jose Maria; González-Porras, Jose Ramon; Jiménez, Cristina; Benito, Rocio; Ordoñez, Gonzalo R; Álvarez-Román, Maria Teresa; Fontecha, M Elena; Janusz, Kamila; Castillo, David; Fisac, Rosa María; García-Frade, Luis Javier; Aguilar, Carlos; Martínez, María Paz; Bermejo, Nuria; Herrero, Sonia; Balanzategui, Ana; Martin-Antorán, Jose Manuel; Ramos, Rafael; Cebeiro, Maria Jose; Pardal, Emilia; Aguilera, Carmen; Pérez-Gutierrez, Belen; Prieto, Manuel; Riesco, Susana; Mendoza, Maria Carmen; Benito, Ana; Hortal Benito-Sendin, Ana; Jiménez-Yuste, Víctor; Hernández-Rivas, Jesus Maria; García-Sanz, Ramon; González-Díaz, Marcos; Sarasquete, Maria Eugenia

2017-01-05

Currently, molecular diagnosis of haemophilia A and B (HA and HB) highlights the excess risk-inhibitor development associated with specific mutations, and enables carrier testing of female relatives and prenatal or preimplantation genetic diagnosis. Molecular testing for HA also helps distinguish it from von Willebrand disease (VWD). Next-generation sequencing (NGS) allows simultaneous investigation of several complete genes, even though they may span very extensive regions. This study aimed to evaluate the usefulness of a molecular algorithm employing an NGS approach for sequencing the complete F8, F9 and VWF genes. The proposed algorithm includes the detection of inversions of introns 1 and 22, an NGS custom panel (the entire F8, F9 and VWF genes), and multiplex ligation-dependent probe amplification (MLPA) analysis. A total of 102 samples (97 FVIII- and FIX-deficient patients, and five female carriers) were studied. IVS-22 screening identified 11 out of 20 severe HA patients and one female carrier. IVS-1 analysis did not reveal any alterations. The NGS approach gave positive results in 88 cases, allowing the differential diagnosis of mild/moderate HA and VWD in eight cases. MLPA confirmed one large exon deletion. Only one case did have no pathogenic variants. The proposed algorithm had an overall success rate of 99 %. In conclusion, our evaluation demonstrates that this algorithm can reliably identify pathogenic variants and diagnose patients with HA, HB or VWD.

Decrease of hemostatic cardiovascular risk factors by aggressive vs. conventional atorvastatin treatment in patients with Type 2 diabetes mellitus.

NARCIS (Netherlands)

Ree, M.A. van de; Maat, M.P. de; Kluft, C.; Meinders, A.E.; Princen, H.M.; Huisman, M.V.

2003-01-01

BACKGROUND: Patients with Type 2 diabetes mellitus have increased levels of hemostatic risk variables for cardiovascular disease, such as fibrinogen, von Willebrand factor (VWF), factor (F)VIIa, d-dimer and plasminogen activator inhibitor-1 (PAI-1). OBJECTIVES: To evaluate the effect of aggressive

Next-generation detection of antigen-responsive T cells using DNA barcode-labeled peptidemajor histocompatibility complex I multimers

DEFF Research Database (Denmark)

Bentzen, Amalie Kai; Marquard, Andrea Marion; Lyngaa, Rikke Birgitte

2016-01-01

diversity of T cell recognition in humans. Consequently it has been impossible to comprehensively analyze T cell responsiveness in cancer, infectious and autoimmune diseases. We present and validate a novel technology that enables parallel detection of numerous different peptide-MHC responsive T cells...... with combinatorial encoding of fluorescent-labeled MHC multimers. Finally, we have demonstrated that this technology can be applied for multiplex T cell detection both in limited biological samples, such as uncultured tumor material, and for simultaneous assessment of target recognition and functional capability...... of T cells. This technology enables true high-throughput detection of antigen-responsive T cells and will advance our understanding of immune recognition from model antigens to genomewide immune assessments on a personalized basis....

Interference from lupus anticoagulant on von Willebrand factor measurement in splenic marginal zone lymphoma

DEFF Research Database (Denmark)

Vinholt, Pernille J; Nybo, Mads

2015-01-01

We present a case concerning a patient with splenic marginal zone lymphoma (SMZL) and isolated prolonged activated partial thromboplastin time (aPTT) caused by lupus anticoagulant. Von Willebrand factor (VWF) activity and antigen were immeasurable by latex particle immunoturbidimetric assays...

Thrombomodulin, von Willebrand factor and E-selectin as plasma markers of endothelial damage/dysfunction and activation in pregnancy induced hypertension.

Science.gov (United States)

Nadar, Sunil K; Al Yemeni, Eman; Blann, Andrew D; Lip, Gregory Y H

2004-01-01

Endothelial disturbance (whether activation, dysfunction or damage) is a likely pathogenic mechanism in pre-eclampsia and pregnancy-induced hypertension (PIH). We set out to determine which of three plasma markers of endothelial disturbance, indicating endothelial activation (E-selectin) or damage/dysfunction (von Willebrand factor (vWf), soluble thrombomodulin), would provide the best discriminator of PIH compared to normotensive pregnancy. Cross-sectional study of 36 consecutive women with PIH (age 31+/-6 years) and 36 consecutive women with normotensive pregnancies (age 29+/-5 years) of similar parity. Plasma levels of vWf, E-selectin and thrombomodulin were measured using ELISA. As expected, women with PIH had significantly higher levels of plasma vWf (by 19%, p=0.003), E-selectin (by 40%, p<0.001) and thrombomodulin (by 61%, p=0.01) than normotensive women. However, on stepwise multiple regression analysis, only thrombomodulin was an independent significant predictor of the presence of PIH (p=0.023). We conclude that although vWf, E-selectin and thrombomodulin are all raised in PIH, only thrombomodulin was independently associated with PIH. This molecule could potentially be useful in monitoring and in providing clues in aetiology and pathophysiology, and may have implications for the clinical complications associated with PIH.

Produção de multimídia e acessibilidade em cursos de aprendizagem a distância/Multimedia production and accessibility on distance learning courses

Directory of Open Access Journals (Sweden)

Joni A. Amorim

2009-06-01

Full Text Available Estudantes online que são surdos podem encontrar diferentes barreiras em cursos baseados na Web incluindo falta de imagens relacionadas ao conteúdo em páginas tomadas por texto. As diferentes barreiras podem diminuir a compreensão para pessoas cuja primeira língua seja a linguagem de sinais ao invés da linguagem escrita, um desafio para pesquisadores e professores interessados em desenvolver conteúdo multimídia. A combinação de texto, imagem, áudio e vídeo foi potencializada devido à convergência digital e passa a caracterizar os textos virtuais. O uso de multimídia agora permite diferentes efeitos na elaboração de significados. Nesta perspectiva de mudanças constantes, este artigo busca discutir alguns dos muitos desafios para o oferecimento de Cursos de Graduação em larga escala, apresentando algumas das características dos Cursos de Graduação em Letras-Libras. Também se discute a acessibilidade de conteúdo educacional digital multimídia no contexto de um projeto em andamento na UNICAMP.Online students who are deaf may encounter different barriers on Web based courses including lack of content-related images in pages full of text. The different barriers can slow comprehension for people whose first language may be a sign language instead of a written language, a challenge for researchers and teachers interested in developing multimedia content. The intermix of text, image, audio, and video has been increased due to the digital convergence and characterize the virtual texts. Multimedia usage now brings different effects on meaning making. In this perspective, this paper intends to discuss some of the many challenges in the offer of large scale undergraduate courses presenting some characteristics of a course on the Brazilian Sign Language. The paper discusses educational digital multimedia content accessibility in the context of an ongoing project at UNICAMP.

Dynamics of von Willebrand factor reactivity in sickle cell disease during vaso-occlusive crisis and steady state

NARCIS (Netherlands)

Sins, J. W. R.; Schimmel, M.; Luken, B. M.; Nur, E.; Zeerleder, S. S.; van Tuijn, C. F. J.; Brandjes, D. P. M.; Kopatz, W. F.; Urbanus, R. T.; Meijers, J. C. M.; Biemond, B. J.; Fijnvandraat, K.

2017-01-01

Background: Endothelial activation plays a central role in the pathophysiology of vaso-occlusion in sickle cell disease (SCD), facilitating adhesive interactions with circulating blood cells. Upon activation, various adhesive molecules are expressed, including von Willebrand factor (VWF). Increased

Neuropeptide delivery to the brain: a von Willebrand factor signal peptide to direct neuropeptide secretion

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de Backer Marijke WA

2010-08-01

Full Text Available Abstract Background Multiple neuropeptides, sometimes with opposing functions, can be produced from one precursor gene. To study the roles of the different neuropeptides encoded by one large precursor we developed a method to overexpress minigenes and establish local secretion. Results We fused the signal peptide from the Von Willebrand Factor (VWF to a furin site followed by a processed form of the Agouti related protein (AgRP, AgRP83-132 or α-melanocyte stimulating hormone. In vitro, these minigenes were secreted and biologically active. Additionally, the proteins of the minigenes were not transported into projections of primary neurons, thereby ensuring local release. In vivo administration of VWF-AgRP83-132 , using an adeno-associated viral vector as a delivery vehicle, into the paraventricular hypothalamus increased body weight and food intake of these rats compared to rats which received a control vector. Conclusions This study demonstrated that removal of the N-terminal part of full length AgRP and addition of a VWF signal peptide is a successful strategy to deliver neuropeptide minigenes to the brain and establish local neuropeptide secretion.

Functional variation in the arginine vasopressin 2 receptor as a modifier of human plasma von Willebrand factor levels

DEFF Research Database (Denmark)

Nossent, Anne Yaël; Robben, J H; Deen, P M T

2010-01-01

SUMMARY OBJECTIVES: Stimulation of arginine vasopressin 2 receptor (V2R) with arginine vasopressin (AVP) results in a rise in von Willebrand factor (VWF) and factor VIII plasma levels. We hypothesized that gain-of-function variations in the V2R gene (AVPR2) would lead to higher plasma levels of V...

Von Willebrand Factor Gene Variants Associate with Herpes simplex Encephalitis.

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Nada Abdelmagid

Full Text Available Herpes simplex encephalitis (HSE is a rare complication of Herpes simplex virus type-1 infection. It results in severe parenchymal damage in the brain. Although viral latency in neurons is very common in the population, it remains unclear why certain individuals develop HSE. Here we explore potential host genetic variants predisposing to HSE. In order to investigate this we used a rat HSE model comparing the HSE susceptible SHR (Spontaneously Hypertensive Rats with the asymptomatic infection of BN (Brown Norway. Notably, both strains have HSV-1 spread to the CNS at four days after infection. A genome wide linkage analysis of 29 infected HXB/BXH RILs (recombinant inbred lines-generated from the prior two strains, displayed variable susceptibility to HSE enabling the definition of a significant QTL (quantitative trait locus named Hse6 towards the end of chromosome 4 (160.89-174Mb containing the Vwf (von Willebrand factor gene. This was the only gene in the QTL with both cis-regulation in the brain and included several non-synonymous SNPs (single nucleotide polymorphism. Intriguingly, in human chromosome 12 several SNPs within the intronic region between exon 43 and 44 of the VWF gene were associated with human HSE pathogenesis. In particular, rs917859 is nominally associated with an odds ratio of 1.5 (95% CI 1.11-2.02; p-value = 0.008 after genotyping in 115 HSE cases and 428 controls. Although there are possibly several genetic and environmental factors involved in development of HSE, our study identifies variants of the VWF gene as candidates for susceptibility in experimental and human HSE.

Elevated levels of von Willebrand factor and high mobility group box 1 (HMGB1) are associated with disease severity and clinical outcome of scrub typhus.

Science.gov (United States)

Chen, Hongliu; Ning, Zong; Qiu, Ying; Liao, Yuanli; Chang, Haihua; Ai, Yuanyuan; Wei, Yinghua; Deng, Yiming; Shen, Ying

2017-08-01

This study aimed to investigate whether von Willebrand factor (vWF) and high mobility group box 1 (HMGB1) are associated with the severity and clinical outcome of scrub typhus and to seek novel biomarkers for surveillance and prediction of the prognosis of this infection. Serum concentrations of vWF and HMGB1 were measured twice by ELISA for scrub typhus patients (n=103), once prior to doxycycline therapy and then on day 7 of doxycycline therapy; concentrations were measured once for healthy controls (n=32). Among the total 103 patients enrolled, 38 had disease complicated by multiple organ dysfunction syndrome (MODS). Serum concentrations of vWF and HMGB1 were significantly higher in all the patients than in the healthy controls, both prior to doxycycline treatment and on day 7 of doxycycline treatment (pscrub typhus (area under the curve (AUC)=0.864, p=0.001, and AUC=0.862, p=0.001, respectively). Elevated levels of vWF and HMGB1 are associated with the severity and clinical outcome of scrub typhus. These represent possible new biomarkers for use in the assessment and prognostic prediction of this infection. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Projet de conception d'un Espace multimédia à la Bibliothèque de la Ville de La Chaux-de-Fonds

OpenAIRE

Emmenegger, Isabelle; Schmutz, Thomas; Cotting, Patrick

2017-01-01

Cette étude a pour objectif de servir de base de travail pour la création et le développement d'un Espace multimédia à la Bibliothèque de la Ville de La Chaux-de-Fonds (BVCF). Elle décrit l'environnement général (contexte, état des lieux) des bibliothèques de lecture publique en Suisse et dans le monde, et aborde les problématiques des nouvelles technologies de l'information et de la communication (NTIC), des nouvelles pratiques de consommation de biens culturels audiovisuels ainsi que celles...

Modelo computacional para o gerenciamento de dados e exames de pacientes para o acompanhamento remoto por meio de conferência multimídia Computational model for data and patients' exams management for remote follow-up by multimedia conferences

Directory of Open Access Journals (Sweden)

Huei Diana Lee

2010-12-01

Full Text Available OBJETIVO: Desenvolver um modelo computacional para aquisição, gerenciamento e armazenamento de dados e exames de pacientes, e definir uma arquitetura de conferência multimídia para o acompanhamento remoto de exames. MATERIAIS E MÉTODOS: Definiu-se uma arquitetura computacional para a aquisição de exames a partir de equipamentos hospitalares, e para o armazenamento e gerenciamento de dados e exames de pacientes foram utilizados o servidor de aplicações Jboss, o sistema gerenciador de banco de dados MySQL, o servidor de páginas Apache e o framework Jboss-Seam para o desenvolvimento de aplicações. Para a conferência multimídia, foi aplicado um estudo de caso utilizando a arquitetura Openmeetings. RESULTADOS: Foram definidos modelos computacionais para o gerenciamento consistente e seguro de dados e exames de pacientes e estudou-se uma arquitetura para conferência multimídia. CONCLUSÃO: Os modelos computacionais, o protótipo implementado e a arquitetura de conferência multimídia avaliada poderão ser aplicados em situações reais da área médica, contribuindo para o acompanhamento remoto de pacientes.OBJECTIVE: To develop a computational model for acquisition, management and storing data and patients' exams, and to define a multimedia conference architecture to remote patients' follow-up. MATERIALS AND METHODS: A computational architecture was defined to acquire exams' information from hospital equipment and to store and manage patients' data and exams using the JBoss application server, the MySql database manager system, the Apache web page server and the Jboss Seam framework for application development. For multimedia conference, a case study using the Openmeetins architecture was performed. RESULTS: computational models intended to the consistent and safe management of data and patients' exams were defined and a multimedia conference architecture was studied. CONCLUSION: The computational models, the prototype developed and

Von Willebrand's disease: case report and review of literature.

Science.gov (United States)

Echahdi, Hanae; El Hasbaoui, Brahim; El Khorassani, Mohamed; Agadr, Aomar; Khattab, Mohamed

2017-01-01

Von Willebrand Disease (VWD) is the most common human inherited bleeding disorder due to a defect of Von Willebrand Factor (VWF), which a glycoprotein crucial for platelet adhesion to the subendothelium after vascular injury. VWD include quantitative defects of VWF, either partial (type 1 with VWF levels < 50 IU/dL) or virtually total (type 3 with undetectable VWF levels) and also qualitative defects of VWF (type 2 variants with discrepant antigenic and functional VWF levels). The most bleeding forms of VWD usually do not concern type 1 patients with the mildest VWF defects (VWF levels between 30 and 50IU/dL). Von willebrand factor is a complex multimeric protein with two functions: it forms a bridge between the platelets and areas of vascular damage and it binds to and stabilizes factor VIII, which is necessary for the clotting cascade. By taking a clinical history of bleeding (mucocutaneous bleeding symptoms suggestive of a primary haemostatic disorder, a quantitative or qualitative abnormality of VWF is possible) it is important to think about VWD and to make the appropriate diagnosis. If the VWD is suspected diagnostic tests should include an activated partial thromboplastin time, bleeding time, factor VIII: C Ristocetin cofactor and vWF antigen. Additional testing of ristocetin induced plattlet adhesion (RIPA) the multimeric structure and collagen binding test and genanalysis allow diagnosing the different types of von. Willebrand Disease. The treatment of choice in mild forms is the synthetic agent desmopressin. In patients with severe type 1, type 2B, 2N and type 3 or in people who do not response to desmopressin, the appropriate treatment is a factor VIII concentrate that is rich of VWF. We report a case of infant in 27-month-old boy who had been referred due to haemorrhagic shock. His birth histories, his familie's social history and developmental milestones were unremarkable. He was born at full term with no antenatal or perinatal complications. Prior to

Estratégias comunicacionais de Serralves: do espaço físico ao espaço multimédia

OpenAIRE

Ramos, Ana Sofia Silva

2012-01-01

O presente estudo visa a análise das estratégias comunicacionais do Museu de Arte Contemporânea de Serralves (MACS) através da observação da articulação entre o espaço expositivo e os espaços multimédia criados pela instituição. Esta tese pretende investigar a importância dos espaços de exposição, físico e digital, e de que forma estes se tornam ambientes dinamizadores de novas experiências e interpretações das obras por parte do público. Nesse sentido, dar-se­á ênfase à análise das car...

Usos e apropriações de multimídias na educação para a biodiversidade em escolas de Belém/PA

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Mayara Santos Maciel

2016-01-01

Full Text Available Esta pesquisa, realizada no âmbito do Programa de Capacitação Institucional através do Museu Paraense Emilio Goeldi/MCTI, identificou as percepções sobre o conceito de biodiversidade em duas comunidades escolares de Ensino Fundamental e Médio da cidade de Belém do Pará - Brasil, vinculadas aos sistemas municipal e estadual de ensino, a saber: Fundação Centro de Referência em Educação Ambiental Professor Eidorfe Moreira e Escola Estadual de Ensino Fundamental e Médio Vilhena Alves. Também identificou como as Tecnologias da Informação e da Comunicação e multimídias atuam como mediadoras dos processos de ensino e aprendizado sobre biodiversidade nestas comunidades. Como metodologia foi utilizada a pesquisa-ação com observação participante (PERUZZO, 2003 e entrevistas em profundidade do tipo semi-abertas com questões semi-estruturadas (Duarte, 2009. Concluiu-se que o conceito de biodiversidade deve ser melhor trabalhado em âmbito escolar, de uma forma estruturada e com o auxílio pedagógico das TICs, cujo uso educativo deve ser favorecido com melhores investimentos na educação pública, principalmente na formação e sensibilização de professores para o uso pedagógico das TICs e multimídias.

LMI Based Robust Blood Glucose Regulation in Type-1 Diabetes Patient with Daily Multi-meal Ingestion

Science.gov (United States)

Mandal, S.; Bhattacharjee, A.; Sutradhar, A.

2014-04-01

This paper illustrates the design of a robust output feedback H ∞ controller for the nonlinear glucose-insulin (GI) process in a type-1 diabetes patient to deliver insulin through intravenous infusion device. The H ∞ design specification have been realized using the concept of linear matrix inequality (LMI) and the LMI approach has been used to quadratically stabilize the GI process via output feedback H ∞ controller. The controller has been designed on the basis of full 19th order linearized state-space model generated from the modified Sorensen's nonlinear model of GI process. The resulting controller has been tested with the nonlinear patient model (the modified Sorensen's model) in presence of patient parameter variations and other uncertainty conditions. The performance of the controller was assessed in terms of its ability to track the normoglycemic set point of 81 mg/dl with a typical multi-meal disturbance throughout a day that yields robust performance and noise rejection.

The primary haemostasis is more preserved in thrombocytopenic patients with liver cirrhosis than cancer

DEFF Research Database (Denmark)

Vinholt, Pernille Just; Alnor, Anne B; Nybo, Mads

2018-01-01

aggregation using impedance aggregometry (Multiplate Analyzer), von Willebrand factor antigen (VWF:Ag), VWF:ristocetin-cofactor activity (VWF:RCo), activated partial thromboplastin time (aPTT), coagulation factor VIII, fibrinogen, and thrombin generation in adult hospitalized patients with platelet count less...... in patients with cirrhosis than cancer, 416 AU × min (IQR 257-676) versus 145 AU × min (IQR 50-326) for collagen-induced platelet aggregation, P time (aPTT), coagulation factor VIII, or thrombin generation between the patient groups...

Architecture and Assembly of HIV Integrase Multimers in the Absence of DNA Substrates*

Science.gov (United States)

Bojja, Ravi Shankar; Andrake, Mark D.; Merkel, George; Weigand, Steven; Dunbrack, Roland L.; Skalka, Anna Marie

2013-01-01

We have applied small angle x-ray scattering and protein cross-linking coupled with mass spectrometry to determine the architectures of full-length HIV integrase (IN) dimers in solution. By blocking interactions that stabilize either a core-core domain interface or N-terminal domain intermolecular contacts, we show that full-length HIV IN can form two dimer types. One is an expected dimer, characterized by interactions between two catalytic core domains. The other dimer is stabilized by interactions of the N-terminal domain of one monomer with the C-terminal domain and catalytic core domain of the second monomer as well as direct interactions between the two C-terminal domains. This organization is similar to the “reaching dimer” previously described for wild type ASV apoIN and resembles the inner, substrate binding dimer in the crystal structure of the PFV intasome. Results from our small angle x-ray scattering and modeling studies indicate that in the absence of its DNA substrate, the HIV IN tetramer assembles as two stacked reaching dimers that are stabilized by core-core interactions. These models of full-length HIV IN provide new insight into multimer assembly and suggest additional approaches for enzyme inhibition. PMID:23322775

Single molecule force spectroscopy data and BD- and MD simulations on the blood protein von Willebrand factor

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Sandra Posch

2016-09-01

Full Text Available We here give information for a deeper understanding of single molecule force spectroscopy (SMFS data through the example of the blood protein von Willebrand factor (VWF. It is also shown, how fitting of rupture forces versus loading rate profiles in the molecular dynamics (MD loading-rate range can be used to demonstrate the qualitative agreement between SMFS and MD simulations. The recently developed model by Bullerjahn, Sturm, and Kroy (BSK was used for this demonstration. Further, Brownian dynamics (BD simulations, which can be utilized to estimate the lifetimes of intramolecular VWF interactions under physiological shear, are described. For interpretation and discussion of the methods and data presented here, we would like to directly point the reader to the related research paper, “Mutual A domain interactions in the force sensing protein von Willebrand Factor” (Posch et al., 2016 [1]. Keywords: Atomic force microscopy, Single molecule force spectroscopy, Molecular dynamics simulation, Brownian dynamics simulation, von Willebrand factor

Mechanical circulatory support is associated with loss of platelet receptors glycoprotein Ibα and glycoprotein VI.

Science.gov (United States)

Lukito, P; Wong, A; Jing, J; Arthur, J F; Marasco, S F; Murphy, D A; Bergin, P J; Shaw, J A; Collecutt, M; Andrews, R K; Gardiner, E E; Davis, A K

2016-11-01

Essentials Relationship of acquired von Willebrand disease (VWD) and platelet dysfunction is explored. Patients with ventricular assist devices and on extracorporeal membrane oxygenation are investigated. Acquired VWD and platelet receptor shedding is demonstrated in the majority of patients. Loss of platelet adhesion receptors glycoprotein (GP) Ibα and GPVI may increase bleeding risk. Background Ventricular assist devices (VADs) and extracorporeal membrane oxygenation (ECMO) are associated with bleeding that is not fully explained by anticoagulant or antiplatelet use. Exposure of platelets to elevated shear in vitro leads to increased shedding. Objectives To investigate whether loss of platelet receptors occurs in vivo, and the relationship with acquired von Willebrand syndrome (AVWS). Methods Platelet counts, coagulation tests and von Willebrand factor (VWF) analyses were performed on samples from 21 continuous flow VAD (CF-VAD), 20 ECMO, 12 heart failure and seven aortic stenosis patients. Levels of platelet receptors were measured by flow cytometry or ELISA. Results The loss of high molecular weight VWF multimers was observed in 18 of 19 CF-VAD and 14 of 20 ECMO patients, consistent with AVWS. Platelet receptor shedding was demonstrated by elevated soluble glycoprotein (GP) VI levels in plasma and significantly reduced surface GPIbα and GPVI levels in CF-VAD and ECMO patients as compared with healthy donors. Platelet receptor levels were also significantly reduced in heart failure patients. Conclusions These data link AVWS and increased platelet receptor shedding in patients with CF-VADs or ECMO for the first time. Loss of the platelet surface receptors GPIbα and GPVI in heart failure, CF-VAD and ECMO patients may contribute to ablated platelet adhesion/activation, and limit thrombus formation under high/pathologic shear conditions. © 2016 International Society on Thrombosis and Haemostasis.

Towards personalised therapy for von Willebrand disease: a future role for recombinant products.

Science.gov (United States)

Favaloro, Emmanuel J

2016-05-01

von Willebrand disease (VWD) is reportedly the most common bleeding disorder and is caused by deficiencies and/or defects in the adhesive plasma protein von Willebrand factor (VWF). Functionally, normal VWF prevents bleeding by promoting both primary and secondary haemostasis. In respect to primary haemostasis, VWF binds to both platelets and sub-endothelial matrix components, especially collagen, to anchor platelets to damaged vascular tissue and promote thrombus formation. VWF also stabilises and protects factor VIII in the circulation, delivering FVIII to the site of injury, which then facilitates secondary haemostasis and fibrin formation/thrombus stabilisation. As a result of this, patients with VWD suffer a bleeding diathesis reflective of a primary defect caused by defective/deficient VWF, which in some patients is compounded by a reduction in FVIII. Management of VWD, therefore, chiefly entails replacement of VWF, and sometimes also FVIII, to protect against bleeding. The current report principally focuses on the future potential for "personalised" management of VWD, given the emerging options in recombinant therapies. Recombinant VWF has been developed and is undergoing clinical trials, and this promising therapy may soon change the way in which VWD is managed. In particular, we can envisage a personalised treatment approach using recombinant VWF, with or without recombinant FVIII, depending on the type of VWD, the extent of deficiencies, and the period and duration of treatment.

Protéolyse du facteur Willebrand et cardiopathies à forces de cisaillement élevées : nouvelles approches diagnostiques et thérapeutiques

OpenAIRE

Rauch , Antoine

2014-01-01

In the first part of the thesis, we describe a novel approach based on antibody-based therapy to prevent the acquired von Willebrand factor (VWF) degradation observed in continuous-flow mechanical circulatory assist device therapy. Via a murine monoclonal antibody directed against VWF D4 domain and thus interfering with VWF-ADAMTS13 binding, a partial inhibition of VWF degradation is observed in whole blood using an ex vivo circulatory assist device model. In the second part of the thesis, we...

Análisis multimétrico para evaluar contaminación en el río Lerma y lago de Chapala, México

OpenAIRE

López-Hernández, Martín; Ramos-Espinosa, María Guadalupe; Carranza-Fraser, Jorge

2007-01-01

Las técnicas para monitorear la calidad del agua deben ser de bajo costo y considerar varios parámetros para un análisis más eficiente de datos. En este estudio se propone la aplicación de un sistema multimétrico para la bioevaluación de la contaminación en condiciones de sequía (mayo), lluvia (julio) y postlluvia (noviembre) en el cauce principal de la cuenca Lerma-Chapala. La bioevaluación incluyó siete determinaciones fisicoquímicas para el cálculo de un Índice de Calidad del Agua (ICA), u...

Produção de multimídia e acessibilidade em cursos de aprendizagem a distânciaMultimedia production and accessibility on distance learning courses

OpenAIRE

Amorim, Joni A.; Silva, Mariana da Rocha C.

2009-01-01

Estudantes online que são surdos podem encontrar diferentes barreiras em cursos baseados na Web incluindo falta de imagens relacionadas ao conteúdo em páginas tomadas por texto. As diferentes barreiras podem diminuir a compreensão para pessoas cuja primeira língua seja a linguagem de sinais ao invés da linguagem escrita, um desafio para pesquisadores e professores interessados em desenvolver conteúdo multimídia. A combinação de texto, imagem, áudio e vídeo foi potencializada devido à convergê...

Clinical and laboratory variability in a cohort of patients diagnosed with type 1 VWD in the United States.

Science.gov (United States)

Flood, Veronica H; Christopherson, Pamela A; Gill, Joan Cox; Friedman, Kenneth D; Haberichter, Sandra L; Bellissimo, Daniel B; Udani, Rupa A; Dasgupta, Mahua; Hoffmann, Raymond G; Ragni, Margaret V; Shapiro, Amy D; Lusher, Jeanne M; Lentz, Steven R; Abshire, Thomas C; Leissinger, Cindy; Hoots, W Keith; Manco-Johnson, Marilyn J; Gruppo, Ralph A; Boggio, Lisa N; Montgomery, Kate T; Goodeve, Anne C; James, Paula D; Lillicrap, David; Peake, Ian R; Montgomery, Robert R

2016-05-19

von Willebrand disease (VWD) is the most common inherited bleeding disorder, and type 1 VWD is the most common VWD variant. Despite its frequency, diagnosis of type 1 VWD remains the subject of debate. In order to study the spectrum of type 1 VWD in the United States, the Zimmerman Program enrolled 482 subjects with a previous diagnosis of type 1 VWD without stringent laboratory diagnostic criteria. von Willebrand factor (VWF) laboratory testing and full-length VWF gene sequencing was performed for all index cases and healthy control subjects in a central laboratory. Bleeding phenotype was characterized using the International Society on Thrombosis and Haemostasis bleeding assessment tool. At study entry, 64% of subjects had VWF antigen (VWF:Ag) or VWF ristocetin cofactor activity below the lower limit of normal, whereas 36% had normal VWF levels. VWF sequence variations were most frequent in subjects with VWF:Ag <30 IU/dL (82%), whereas subjects with type 1 VWD and VWF:Ag ≥30 IU/dL had an intermediate frequency of variants (44%). Subjects whose VWF testing was normal at study entry had a similar rate of sequence variations as the healthy controls (14%). All subjects with severe type 1 VWD and VWF:Ag ≤5 IU/dL had an abnormal bleeding score (BS), but otherwise BS did not correlate with VWF:Ag. Subjects with a historical diagnosis of type 1 VWD had similar rates of abnormal BS compared with subjects with low VWF levels at study entry. Type 1 VWD in the United States is highly variable, and bleeding symptoms are frequent in this population. © 2016 by The American Society of Hematology.

Evaluation of a multimedia online tool for teaching bronchial hygiene to physical therapy students Avaliação de um recurso multimídia para ensino de higiene brônquica para estudantes de fisioterapia

Directory of Open Access Journals (Sweden)

Cibele C. B. Marques da Silva

2012-02-01

Full Text Available BACKGROUND: Advances in information technology have been widely used in teaching health care professionals. The use of multimedia resources may be important for clinical learning and we are not aware of previous reports using such technology in respiratory physical therapy education. Objectives: Our approach was to evaluate a conventional bronchial hygiene techniques (BHTs course with an interactive online environment, including multimedia resources. METHODS: Previous developed audiovisual support material comprised: physiology, physiopathology and BHTs, accessible to students through the Internet in conjunction with BHTs classes. Two groups of students were compared and both attended regular classes: the on-line group (n=8 received access to online resources, while the control group (n=8 received conventional written material. Student's performance was evaluated before and after the course. RESULTS: A preliminary test (score 0 to 10 was applied before the beginning of the course, showing that the initial knowledge of both groups was comparable [online, 6.75 (SD=0.88 vs. control, 6.125 (SD=1.35; p>0.05]. Two weeks after the end of the course, a second test showed that the online group performed significantly better than the control group [respectively, 7.75 (SD=1.28 vs. 5.93 (SD=0.72; p>0.05]. CONCLUSIONS: The use of a multimedia online resource had a positive impact on student's learning in respiratory therapy field in which instrumental and manual resources are often used and can be explored using this technology.CONTEXTUALIZAÇÃO: As novas tecnologias da informação têm sido amplamente utilizadas no ensino em saúde. O uso de recursos multimídia pode ser importante para o aprendizado clínico, no entanto não há descrição na literatura da aplicação e relevância desses recursos para o ensino de fisioterapia respiratória. OBJETIVOS: Avaliar o impacto de um recurso didático multimídia no ensino de manobras de higiene brônquica (MHB

Mostra fotográfica multimídia: espaços de aprendizagem inovadora em educação ambiental

Directory of Open Access Journals (Sweden)

Clarissa Felkl Prevedello

2017-08-01

Full Text Available Este artigo se refere ao projeto de extensão Mostra Fotográfica Multimídia “Visitando a Cooperativa FRAGET-COOTAFRA”, idealizado pelo Núcleo de Gestão Ambiental Integrada da Reitoria do Instituto Federal Sul-rio-grandense. A proposta teve como objetivo de promover situações de aprendizagem inovadoras sobre a importância socioambiental das cooperativas de reciclagem.  A Mostra foi composta por imagens que retratam o dia a dia da Cooperativa, os processos por onde passa cada tipo de resíduo e as pessoas que lá trabalham e que tiram seu sustento da reciclagem. Registros de som do ambiente interno da Cooperativa também fizeram parte da Mostra, propondo maior ambientação dos visitantes ao tema das fotografias, juntamente com imagens registradas pelos próprios cooperativados, revelando seus pontos de vista sobre o trabalho que realizam.

High circulating osteoprotegerin levels are associated with non-zero blood groups.

Science.gov (United States)

Nagy, Elod Erno; Varga-Fekete, Timea; Puskas, Attila; Kelemen, Piroska; Brassai, Zoltan; Szekeres-Csiki, Katalin; Gombos, Timea; Csanyi, Maria Csilla; Harsfalvi, Jolan

2016-05-26

Osteoprotegerin (OPG) and von Willebrand factor (VWF) form complex within endothelial cells and following secretion. The nature of blood group antigens strongly influences the levels of circulating VWF, but there is no available data concerning its ascendancy on OPG levels. We aimed to assess the relationship of AB0 blood groups with OPG, VWF levels (VWF: Ag) and collagen binding activity (VWF: CB) in peripheral arterial disease (PAD) patients. Functional and laboratory parameters of 105 PAD patients and 109 controls were examined. Results of OPG, VWF: Ag, VWF: CB (ELISA-s) were analysed by comparative statistics, together with clinical data. OPG levels were higher in patients than in controls (4.64 ng/mL vs. 3.68 ng/mL, p blood groups compared to 0-groups both in patients and controls (4.95 ng/mL vs. 3.90 ng/mL, p = 0.012 and 4.09 ng/mL vs. 3.40 ng/mL, p = 0.002). OPG levels are associated to blood group phenotypes and higher in non-0 individuals. Increased OPG levels in PAD characterize disease severity. The significant correlation between OPG and VWF:CB might have functional importance in an atherothrombosis-prone biological environment.

Diagnosis and management of von Willebrand disease: a developing country perspective.

Science.gov (United States)

Nair, Sukesh Chandran; Viswabandya, Auro; Srivastava, Alok

2011-07-01

Special challenges exist in the management of patients with von Willebrand disease (VWD) because of limitations in diagnostic facilities and therapeutic options. However, even within these limitations, it is possible to establish comprehensive services for this condition. Our data show that among 202 patients with VWD, 107 were type 3, 62 were type 1, and the others different categories of type 2. Basic tests such as bleeding time and activated partial thromboplastin time with factor (F)VIII coagulant are able to diagnose most of those with severe disease. We have been able to adapt the specific tests such as von Willebrand factor (VWF) ristocetin cofactor and VWF antigen from the tedious batched manual methods to cost-effective automated methods on advanced coagulometers. Discriminatory tests such as VWF collagen binding, VWF:FVIIIB, ristocetin-induced platelet agglutination (RIPA) are done in batches. Therapeutic options and for the treatment of bleeding include desmopressin, cryoprecipitate, and intermediate purity VWF-containing clotting factor concentrates. Tranexamic acid is also widely used as well as hormonal therapy for menorrhagia. We have also shown that modest doses of intermediate purity FVIII (Koate DVI; Talecris Biotherapeutics, Raleigh, NC, USA) at 35 IU/kg preoperatively and 10 to 20 IU/kg after that are sufficient for surgical hemostasis in these patients. © Thieme Medical Publishers.

Distribution of von Willebrand factor levels in young women with and without bleeding symptoms: influence of ABO blood group and promoter haplotypes

DEFF Research Database (Denmark)

Lethagen, S.; Hillarp, A.; Ekholm, C.

2008-01-01

menstrual cycle, or the use of oral contraceptives. No case fulfilled the diagnostic criteria for VWD. In conclusion, low VWF:RCo was significantly more frequent in females with bleeding symptoms. However, we found no case fulfilling strict diagnostic criteria for VWD. The ABO blood group was a strong....... It was the objective of the present study to evaluate the distribution of VWF levels in young females with or without bleeding symptoms in this population, and the influence of ABO blood group and promoter haplotypes on VWF levels and to identify a possible increased prevalence of VWD in females with bleeding symptoms...

"Amor e sexo: mitos, verdades e fantasias": jovens avaliam potencial de material multimídia educativo em saúde "Love and sex: myths, truths and fantasies": youth evaluation of the multimedia resource as educational health material

Directory of Open Access Journals (Sweden)

Sonia Maria Figueira Mano

2009-01-01

Full Text Available A educação sexual na escola é prática defendida e prescrita pelo Ministério da Educação nos Parâmetros Curriculares Nacionais como eixo transversal ao currículo. O tema é complexo e a proposta expressa demandas específicas, como a formação dos professores e materiais educativos adequados. O Museu da Vida, COC/Fiocruz, desenvolveu o multimídia «Amor e sexo: mitos, verdades e fantasias» e, neste artigo, apresenta a avaliação efetuada por 36 alunos do Ensino Médio de escolas públicas do Rio de Janeiro sobre o produto. A avaliação permitiu identificar o multimídia como recurso educativo capaz de promover o tema sexualidade em situações de aprendizagem. Um recurso do multimídia, denominado Caderno de Perguntas, mostrou-se como espaço de interlocução entre os jovens, permitindo troca anônima de dúvidas e ideias, e alimentando um banco de dados que permite aos professores e pesquisadores conhecerem melhor o pensamento dos adolescentes.Sex education in schools is advised and agreed as a universal theme in the National Curriculum of the Brazilian Education Ministry. This subject is complex and the proposal expresses specific needs, such as teacher training and the support of educational materials. The Museum of Life, COC/Fiocruz, developed the multimedia resource, "Love and Sex: myths, truths and fantasies" and this study presents the results of the evaluation made by 36 high school students from public schools, in Rio de Janeiro about the multimedia resource. The evaluation identified it as an educational resource, able to promote dialogue and support the the theme sexuality in teaching situations. A multimedia resource, called Answers Notebook, gives a dialogue space between adolescents, allowing anonymity in the exchange of doubts and ideas, and feeding into a database that allow teachers and professionals to know better how adolescents think.

Selective Protein Extraction from Chlorobium tepidum Chlorosomes Using Detergents. Evidence That CsmA Forms Multimers and Binds Bacteriochlorophyll a

DEFF Research Database (Denmark)

Bryant, Donald A; Vassilieva, Elena V; Frigaard, Niels-Ulrik

2002-01-01

and location of this BChl a are not yet clearly understood. Chlorosomes were treated with sodium dodecyl sulfate (SDS), Lubrol PX, or Triton X-100, separately or in combination with 1-hexanol, and the extracted components were separated from the residual chlorosomes by ultrafiltration on centrifugal filters....... When chlorosomes were treated with low concentrations of SDS, all proteins except CsmA were extracted. However, this treatment did not significantly alter the size and shape of the chlorosomes, did not extract the BChl a, and caused only minor changes in the absorption spectrum of the chlorosomes....... Cross-linking studies with SDS-treated chlorosomes revealed the presence of multimers of the major chlorosome protein, CsmA, up to homooctamers. Extraction of chlorosomes with SDS and 1-hexanol solubilized all ten chlorosome envelope proteins as well as BChl a. Although the size and shape...

Complement activation, endothelial dysfunction, insulin resistance and chronic heart failure

DEFF Research Database (Denmark)

Bjerre, M.; Kistorp, C.; Hansen, T.K.

2010-01-01

CRP), endothelial activation (soluble E-selectin, sEsel)), endothelial damage/dysfunction (von Willebrand factor, vWf) and insulin resistance (IR) and prognosis in CHF remains unknown. Design. We investigated the association(s) between plasma sMAC, hsCRP, sEsel, vWf and IR (assessed by homeostatic model assessment...

Von Willebrand disease protects against arterial thrombosis

NARCIS (Netherlands)

Sanders, Y.V.; Eikenboom, J.C.; De Wee, E.M.; Van Der Bom, J.G.; Cnossen, M.H.; Degenaar-Dujardin, M.E.; Fijnvandraat, K.; Kamphuisen, P.W.; Laros-Van Gorkum, B.A.; Meijer, K.; Mauser -Bunschoten, E.P.; Leebee k, F.W.

Background and Aims: Von Willebrand disease (VWD) is caused by reduced levels of or dysfunctional von Willebrand factor (VWF) and is characterized by a bleeding tendency. It is well known that individuals with high VWF levels have a higher risk for arterial thrombosis. Although it has never been

Analysis of expression of von Willebrand factor, endothelin-1, vascular endothelial growth factor in Budd-Chiari syndrome with membranous obstruction

International Nuclear Information System (INIS)

Han Xinqiang; Zu Maoheng

2011-01-01

Objective: To investigate whether the injured vascular endothelial plays an important role in the membranous formation of the inferior vena cava (IVC). Methods: There were 40 cases of membranous obstruction of inferior vena cava (MOVC) in the experimental group and 40 arrhythmic inpatients in the control group from affiliated hospital. There were 23 males and 17 females in experimental group while 21 males and 19 females in control group, and the age were (41.8±8.1) yrs and (43.2± 7.6) yrs respectively. All of them had no anti-coagulation (clotting) drug history and smoking history, no hypertension, no pulmonary artery hypertension, no coronary heart disease, no valvular disease, no myocardial disease, no blood disease, no diabetes, no connective tissue disease and malignancy, and liver and renal function must be normal. And then the serum concentrations of von Willebrand factor (vWF), endothelin-l (ET-1), vascular endothelial growth factor (VEGF) were defined by enzyme-linked immunosorbent assay (ELISA). The results were analyzed with independent sample t-test. Results: In MOVC patients, the serum concentrations of vWF, ET-1 and VEGF [(37.8±6.6) μg/L, (31.9± 6.0) ng/L, (20.84±5.78) μg/L] were higher than those in the control group [(3.3±1.3) μg/L, (5.3±1.8) ng/L, (4.2±1.2) μg/L. t=32.65, 26.70, 17.85, P<0.01, respectively]. Conclusions: The injury of vascular endothelium is related to the formation of membrane in the IVC. (authors)

The Molecular Genetics of von Willebrand Disease

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Ergül Berber

2012-12-01

Full Text Available Quantitative and/or qualitative deficiency of von Willebrand factor (vWF is associated with the most common inherited bleeding disease von Willebrand disease (vWD. vWD is a complex disease with clinical and genetic heterogeneity. Incomplete penetrance and variable expression due to genetic and environmental factors contribute to its complexity. vWD also has a complex molecular pathogenesis. Some vWF gene mutations are associated with the affected vWF biosynthesis and multimerization, whereas others are associated with increased clearance and functional impairment. Moreover, in addition to a particular mutation, type O blood may result in the more severe phenotype. The present review aimed to provide a summary of the current literature on the molecular genetics of vWD.

The molecular genetics of von Willebrand disease.

Science.gov (United States)

Berber, Ergül

2012-12-01

Quantitative and/or qualitative deficiency of von Willebrand factor (vWF) is associated with the most common inherited bleeding disease von Willebrand disease (vWD). vWD is a complex disease with clinical and genetic heterogeneity. Incomplete penetrance and variable expression due to genetic and environmental factors contribute to its complexity. vWD also has a complex molecular pathogenesis. Some vWF gene mutations are associated with the affected vWF biosynthesis and multimerization, whereas others are associated with increased clearance and functional impairment. Moreover, in addition to a particular mutation, type O blood may result in the more severe phenotype. The present review aimed to provide a summary of the current literature on the molecular genetics of vWD. None declared.

Van Willebrand's disease in the Western Cape

African Journals Online (AJOL)

agglutinate normal platelets but does not have an effect on platelets from patients with VWD. The ristocetin co-factor. (RiCo~ assay measures the ability of plasma to agglutinate fixed platelets and is therefore regarded as an indirect measure of VWF activity. Qualitative analysis of VWF antigen. 0JWF-Ag) is required for ...

Characterisation of adiponectin multimers and the IGF axis in humans with a heterozygote mutation in the tyrosine kinase domain of the insulin receptor gene

DEFF Research Database (Denmark)

Højlund, Kurt; Beck-Nielsen, Henning; Flyvbjerg, Allan

2012-01-01

Objective: Low levels of adiponectin, IGF-binding protein (IGFBP)-1, and IGFBP-2, and high levels of leptin correlate with several indices of insulin resistance and risk of type 2 diabetes. However, in insulin receptoropathies plasma adiponectin is paradoxically increased despite severe insulin...... resistance, whereas the IGF-axis is sparsely described. Here, we aimed to characterize the multimeric distribution of adiponectin and the IGF-axis in humans with a heterozygous INSR mutation (Arg1174Gln).Methods: Blood samples obtained in six Arg1174Gln-carriers and 10 lean, healthy controls before and after...... an euglycemic-hyperinsulinemic clamp were examined for plasma adiponectin multimers, leptin, total IGF-I, IGF-II, free IGF-I, IGFBP-1 and IGFBP-2.Results: Despite 10-fold elevated fasting insulin and marked insulin resistance in Arg1174Gln-carriers, the levels of total adiponectin, leptin, IGFBP-1 and IGFBP-2...

Purification and characterization of factor VIII 1,689-Cys: a nonfunctional cofactor occurring in a patient with severe hemophilia A.

Science.gov (United States)

O'Brien, D P; Tuddenham, E G

1989-06-01

We have purified the factor VIII from a CRM+ Hemophilia A plasma (90 U/dL VIII:Ag but 0 U/dL VIII:C) and analyzed the protein before and after thrombin activation by Western blotting with monoclonal antibodies (MoAbs). Normal or patient citrated plasma was ultracentrifuged, cryo-ethanol-precipitated and chromatographed on Sepharose 6B. The void volume fractions were reduced and subjected to ion exchange chromatography yielding material of specific activity approximately 1,000 U/mg protein (VIII:C or VIII:Ag). Factor VIII purified in this way from normal plasma is fully activatable by thrombin with proteolytic fragmentation as previously described by F. Rotblat et al (Biochemistry 24: 4294, 1985). Factor VIII 1,689-Cys has the normal distribution of factor VIII light and heavy chains prior to thrombin activation. After exposure to thrombin the heavy chain polypeptides were fully proteolysed but the light chain was totally resistant to cleavage. This is consistent with the demonstration in the patient's leucocyte DNA of a C to T transition in codon 1,689 converting Arg to Cys at the light chain thrombin cleavage site as previously described by J. Gitschier et al (Blood 72:1022, 1988). Uncleaved light chain of Factor VIII 1,689-Cys is not released from von Willebrand factor (vWF) by thrombin, but this is not the sole cause of the functional defect since the protein purified free of vWF has no coagulant activity. We conclude that the functional defect in factor VIII 1,689-Cys is a consequence of failure to release the acidic peptide from the light chain upon thrombin activation.

Paciente portadora de doença de von Willebrand submetida a cirurgia da valva mitral: uma estratégia para o controle da coagulopatia Patient with von Willebrand disease undergoing mitral valve repair: a strategy for the control of the coagulopathy

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Ally Nader Roquetti Saroute

2007-01-01

Full Text Available Relatamos o caso de uma mulher de 60 anos portadora da doença de von Willebrand tipo I, submetida a cirurgia da valva mitral. A paciente necessitou de cuidados especiais em razão da coagulopatia e foi necessária a utilização de concentrado de fator VIII (VIIIf e fator de von Willebrand (vWf antes, durante e depois da cirurgia. Não houve complicações durante e após a cirurgia. Nove meses depois, a paciente encontra-se assintomática. A correção para valores adequados de VIIIf e vWf permitiu a realização da cirurgia com segurança.We report a case of a 60 year-old woman with von Willebrand disease type I that was submitted to a mitral valve repair. The patient needed special care due coagulopathy and needed VIII factor (VIIIf and von Willebrand factor (vWf, before, during and after surgery. There was no complication during or after surgery. Patient is asymptomatic nine months postoperatively. The correction of VIIIf and vWf allowed the realization of a safety surgery.

Material educacional multimídia interativo sobre movimentos de massa: produção e uso em sala de aula

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Mirley Ribeiro Moreira

2015-06-01

Full Text Available O artigo descreve experiência de produção do material educacional multimídia interativo em código aberto, que objetiva estudar movimentos de massa. A investigação foi realizada por meio da observação do uso de CD educacional em sala de aula, apresentado em turmas de graduação de Ciências da Terra e Engenharia, e aplicação de questionários. Os dados foram graficamente catalogados. Os resultados obtidos sinalizaram que a produção de CDs educacionais facilita a compreensão e fixação da matéria, pois a interatividade desperta a curiosidade dos alunos e promove maior atenção e concentração. Um desafio na utilização do material é a necessidade de mudar o perfil do professor: se por um lado os avanços tecnológicos exigem que ele tenha respostas rápidas, precisas e imediatas para alunos com grande quantidade de informação e acostumados à velocidade da internet, por outro lado muitos docentes ainda se mostram refratários às mudanças, insistindo no estereótipo da relação professor-aluno.

Development of a lectin binding assay to differentiate between recombinant and endogenous proteins in pharmacokinetic studies of protein-biopharmaceuticals.

Science.gov (United States)

Weber, Alfred; Minibeck, Eva; Scheiflinger, Friedrich; Turecek, Peter L

2015-04-10

Human glycoproteins, expressed in hamster cell lines, show similar glycosylation patterns to naturally occurring human molecules except for a minute difference in the linkage of terminal sialic acid: both cell types lack α2,6-galactosyl-sialyltransferase, abundantly expressed in human hepatocytes and responsible for the α2,6-sialylation of circulating glycoproteins. This minute difference, which is currently not known to have any physiological relevance, was the basis for the selective measurement of recombinant glycoproteins in the presence of their endogenous counterparts. The assay is based on using the lectin Sambucus nigra agglutinin (SNA), selectively binding to α2,6-sialylated N-glycans. Using von Willebrand factor (VWF), factor IX (FIX), and factor VIIa (FVIIa), it was demonstrated that (i) the plasma-derived proteins, but not the corresponding recombinant proteins, specifically bind to SNA and (ii) this binding can be used to deplete the plasma-derived proteins. The feasibility of this approach was confirmed in spike-recovery studies for all three recombinant coagulation proteins in human plasma and for recombinant VWF (rVWF) in macaque plasma. Analysis of plasma samples from macaques after administration of recombinant and a plasma-derived VWF demonstrated the suitability and robustness of this approach. Data showed that rVWF could be selectively measured without changing the ELISAs and furthermore revealed the limitations of baseline adjustment using a single measurement of the predose concentration only. The SNA gel-based depletion procedure can easily be integrated in existing procedures as a specific sample pre-treatment step. While ELISA-based methods were used to measure the recombinant coagulation proteins in the supernatants obtained by depletion, this procedure is applicable for all biochemical analyses. Copyright © 2015 Elsevier B.V. All rights reserved.

ENDOTHELIUM LESION MARKERS AND THROMBOCYTE AGGREGATION IN CHRONIC HEPATITIS AND HEPATIC CIRRHOSIS

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A. P. Shchekotova

2012-01-01

Full Text Available Aim — to estimate endothelium lesion, quantity and thrombocyte aggregation function correlation in viral chronic hepatitis C (CHC and hepatic cirrhosis (HC.Materials and methods. 50 CHC patients and 28 HC patients were examined. Using IFA method the total nitric oxide, endothelin‑1, vasculoendothelial growth factor levels, Willebrand factor (vWF activity were investigated, blood plasma desquamated endotheliocyte (DEC number was calculated with Hladovec method, 1978, thrombocyte aggregation (TA with ADP, collagen, ristocetine was determined.Results. DEC and vWF demonstrated correlation in CHC (p = 0.014 and HC (p = 0.000004. In HC patients reliable correlation of all the investigated indices of endothelium lesion with the thrombocyte number and TA was detected, but in CHC patients no correlations were revealed. Thus, significant elevation of TA with ristocetine was noted only in CHC. Decrease in thrombocyte amount among CHC patients and,especially in HC, and heightened vWF activity could change true TA indices. The corrected TA, whose indices in hepatic diseases significantlyincreased, was calculated taking into account the correction factor vWF / thrombocytes that in CHC did not differ from that of healthy patients and in HC was essentially higher.Conclusion. Endothelium dysfunction markers in CH and HC demonstrate correlation with thrombocyte reduction and TA elevation. Determinationof corrected TA permits to reveal disturbances of thrombocyte hemostasis in the form of elevated aggregation in all CHC and HC patients.

The VITRO Score (Von Willebrand Factor Antigen/Thrombocyte Ratio as a New Marker for Clinically Significant Portal Hypertension in Comparison to Other Non-Invasive Parameters of Fibrosis Including ELF Test.

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Stephanie Hametner

Full Text Available Clinically significant portal hypertension (CSPH, defined as hepatic venous pressure gradient (HVPG ≥10 mmHg, causes major complications. HVPG is not always available, so a non-invasive tool to diagnose CSPH would be useful. VWF-Ag can be used to diagnose. Using the VITRO score (the VWF-Ag/platelet ratio instead of VWF-Ag itself improves the diagnostic accuracy of detecting cirrhosis/ fibrosis in HCV patients.This study tested the diagnostic accuracy of VITRO score detecting CSPH compared to HVPG measurement.All patients underwent HVPG testing and were categorised as CSPH or no CSPH. The following patient data were determined: CPS, D'Amico stage, VITRO score, APRI and transient elastography (TE.The analysis included 236 patients; 170 (72% were male, and the median age was 57.9 (35.2-76.3; 95% CI. Disease aetiology included ALD (39.4%, HCV (23.4%, NASH (12.3%, other (8.1% and unknown (11.9%. The CPS showed 140 patients (59.3% with CPS A; 56 (23.7% with CPS B; and 18 (7.6% with CPS C. 136 patients (57.6% had compensated and 100 (42.4% had decompensated cirrhosis; 83.9% had HVPG ≥10 mmHg. The VWF-Ag and the VITRO score increased significantly with worsening HVPG categories (P<0.0001. ROC analysis was performed for the detection of CSPH and showed AUC values of 0.92 for TE, 0.86 for VITRO score, 0.79 for VWF-Ag, 0.68 for ELF and 0.62 for APRI.The VITRO score is an easy way to diagnose CSPH independently of CPS in routine clinical work and may improve the management of patients with cirrhosis.

Effects of breed, gender, exercise and white-coat effect on markers of endothelial function in dogs

DEFF Research Database (Denmark)

Moesgaard, Sophia Gry; Holte, A.V.; Mogensen, T.

2007-01-01

This study examines how systemic biomarkers of endothelial function and nitric oxide metabolism are affected by exercise in dogs. Furthermore, breed variation and white-coat effect have been tested by sampling three different dog breeds both in their home and in a clinical setting. Short......-term exercise increased plasma nitrate and nitrite (NOx) and von Willebrand factor (vWf). There was significant difference between Pointers and the small dog breeds Cairn Terriers and Cavalier King Charles Spaniels in the general plasma levels of vWf and asymmetric dimethylarginine (ADMA9. NOx and vWf were...... significantly higher when the sample was taken in the laboratory cf. at home, whereas ADMA and L-arginine were significantly lower. In conclusion, both short-term exercise and white-coat effect influence several plasma markers of endothelial function depending also on the breed and gender of the dogs...

Biomarkers of coagulation, fibrinolysis, endothelial function, and inflammation in arterialized venous blood

DEFF Research Database (Denmark)

Gram, Anne Sofie; Skov, Jane; Ploug, Thorkil

2014-01-01

Effects of venous blood arterialization on cardiovascular risk markers are still unknown. We evaluated biomarkers of inflammation, coagulation, fibrinolysis, and endothelial function in arterialized compared with regular venous blood. Cubital venipunctures were obtained from 10 healthy volunteers....... Arterialization was generated by 10 min heating of the contralateral hand. Concentrations of albumin, C-reactive protein (CRP), tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor type 1 (PAI-1), and von Willebrand factor (vWF) were measured by validated assays. Concentrations of albumin......, CRP, and vWF were significantly lower in arterialized than in venous blood (albumin: 43.8 g/l and 44.8 g/l, P = 0.02). Differences in CRP and vWF became insignificant after adjusting for albumin. The endogenous thrombin potential (ETP) was significantly higher in arterialized than in venous blood...

Procoagulant reactivity to laboratory acute mental stress in Africans and Caucasians, and its relation to depressive symptoms: the SABPA study.

Science.gov (United States)

von Känel, R; Hamer, M; Malan, N T; Scheepers, K; Meiring, M; Malan, L

2013-11-01

The risk of cardiovascular disease is dramatically increasing in Africans (black). The prothrombotic stress response contributes to atherothrombotic disease and is modulated by depressive symptoms. We examined coagulation reactivity to acute mental stress and its relation to psychological well-being in Africans relative to Caucasians (white). A total of 102 African and 165 Caucasian school teachers underwent the Stroop Color-Word Conflict test. Circulating levels of von Willebrand factor (VWF) antigen, fibrinogen, and D-dimer were measured before and after the Stroop. Cardiovascular reactivity measures were also obtained. All participants completed the Patient Health Questionnaire-9 and the General Health Questionnaire-28 for the assessment of depressive symptoms and total psychological distress, respectively. After controlling for covariates, resting levels of VWF, fibrinogen, and D-dimer were higher in Africans than in Caucasians (all p-values ≤0.006). Depressive symptoms and psychological distress were not significantly associated with resting coagulation measures. Stress reactivity in VWF (pstress when compared with Caucasians. Ethnic differences in the vascular adrenergic stress response might partially explain this finding. Depressive symptoms were associated with exaggerated VWF reactivity in Africans relative to Caucasians. The clinical implications of these findings for Africans need further study.

Quality of Clotting Factor Activity in Fresh Frozen Plasma at Thaw with a Microwave System and after Storage at 4 degrees C for 48 Hours.

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Kuta, Piotr; Hauck-Dlimi, Barbara; Strobel, Julian; Zimmermann, Robert; Eckstein, Reinhold

2016-01-01

Uncontrolled hemorrhage in polytrauma patients usually results in rapid need of blood products. Despite the shorter thawing times of microwave devices for heating fresh frozen plasma (FFP), their use has remained controversial, and just a few laboratory analyses have been published on this topic. The aim of this study was to analyse the quality of clotting factors immediately after thawing FFP with a microwave device and after 48-hour post thaw storage at 4 degrees C. 24 FFP units of all four ABO blood groups (six of each blood group) were thawed with a Transfusio-therm 2000 and later stored at 4 degrees C for 48 hours. Samples were drawn aseptically and investigated on various clotting factors and protein proteases (fibrinogen, antithrombin, FII, FV, FVII, FVIII, FIX, FX, FXI, FXIII, vWF antigen and activity, protein S, and protein C) using standard coagulation and chromogenic assays immediately after thawing and again after a 48-hour storage period at 4 degrees C. All units were tested for both anaerobic and aerobic microbial contamination using standard operating procedures immediately after thawing. After thawing, all coagulation factors and protein protease activities were within normal ranges. Blood group O individuals had approximately 25% lower plasma levels of vWF antigen and activity. After a 48-hour storage period at 4 degrees C, FVIII and FIX activities declined significantly in all blood groups, whereas the remaining clotting factors remained comparably stable. Immediately after rapid thawing using a microwave system, all FFP units contained adequate coagulation factor activities to maintain hemostatic activity at the time of product thaw. The post thaw refrigerated storage caused an anticipated decrease in factor VIII and IX activities, but retained normal coagulation factor levels of many plasma proteins. Therefore we conclude that the Transfusio-therm 2000 has no clinically significant influence on the activity of clotting factors and plasma

Correlation between expressions of hypoxia -inducible factor (HIF-1α, blood vessels density, cell proliferation, and apoptosis intensity in canine fibromas and fibrosarcomas

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Madej Janusz A.

2014-03-01

Full Text Available The study aimed to demonstrate the expression of hypoxia-inducible factor (HIF-1α in soft tissue mesenchymal tumours (fibroma and fibrosarcoma in dogs. An attempt was made to correlate the obtained results with density of blood vessels (expression of von Willebrand Factor, vWF, expression of Ki-67 proliferation antigen, and with intensity of apoptosis in studied tumours. The study was performed on paraffin sections of 15 fibromas and 40 fibrosarcomas sampled from 55 female dogs aged 6 to 16 years. Immunohistochemical staining against HIF-1α, vWF, and Ki-67 was performed. Apoptosis was detected with the use of TUNEL reaction. A significantly higher HIF-1α expression was noted in fibrosarcomas in comparison to fibromas (P < 0.0001. HIF-1α expression in fibromas manifested strong positive correlation with tumour vascularity (r = 0.67, P = 0.007. Moreover, HIF-1α expression in fibrosarcomas manifested a moderate positive correlation with tumour malignancy grade (r = 0.44, P = 0.004, tumour vascularity (r = 0.52, P < 0.001, Ki-67 antigen expression (r = 0.42; P = 0.007, and TUNELpositive cells (r = 0.37, P = 0.017. Expression of HIF-1α was detected in 86.7% of fibroma type tumours and in 100% of fibrosarcomas. In all studied tumours expression of HIF-1α manifested positive correlation with the density of blood vessels, and in fibrosarcomas it correlated also with malignancy grade, intensity of Ki-67 expression, and with intensity of apoptosis in tumour cells.

Translational Medicine Advances in von Willebrand Disease

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Lillicrap, David

2014-01-01

Following the recognition of von Willebrand disease (VWD) in 1926 and the cloning of the gene for von Willebrand factor (VWF) in 1985, significant advances have been made in our fundamental knowledge of both the disease and the protein. Some of this new knowledge has also begun to impact the clinical management of VWD. First, the progressive increase in our understanding of the molecular genetic basis of VWD has resulted in rational applications of molecular testing to complement the current range of phenotypic tests for VWD. These molecular genetic strategies are most effectively directed at the prenatal diagnosis of type 3 VWD and confirmatory testing for types 2B and 2N disease. In contrast, the use of molecular testing to clarify the diagnosis of type 1 VWD is of marginal benefit, at best. In terms of VWD therapies, a new recombinant VWF concentrate has recently completed successful clinical trials and is now awaiting more widespread application. There have even been some pre-clinical successes with VWF gene transfer although the clinical rationale for this therapeutic strategy needs careful consideration. Much more remains to be learnt about the biology of VWF and further translational advances for the enhancement of VWD care will inevitably be realized. PMID:23809112

A variational Bayes discrete mixture test for rare variant association.

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Logsdon, Benjamin A; Dai, James Y; Auer, Paul L; Johnsen, Jill M; Ganesh, Santhi K; Smith, Nicholas L; Wilson, James G; Tracy, Russell P; Lange, Leslie A; Jiao, Shuo; Rich, Stephen S; Lettre, Guillaume; Carlson, Christopher S; Jackson, Rebecca D; O'Donnell, Christopher J; Wurfel, Mark M; Nickerson, Deborah A; Tang, Hua; Reiner, Alexander P; Kooperberg, Charles

2014-01-01

Recently, many statistical methods have been proposed to test for associations between rare genetic variants and complex traits. Most of these methods test for association by aggregating genetic variations within a predefined region, such as a gene. Although there is evidence that "aggregate" tests are more powerful than the single marker test, these tests generally ignore neutral variants and therefore are unable to identify specific variants driving the association with phenotype. We propose a novel aggregate rare-variant test that explicitly models a fraction of variants as neutral, tests associations at the gene-level, and infers the rare-variants driving the association. Simulations show that in the practical scenario where there are many variants within a given region of the genome with only a fraction causal our approach has greater power compared to other popular tests such as the Sequence Kernel Association Test (SKAT), the Weighted Sum Statistic (WSS), and the collapsing method of Morris and Zeggini (MZ). Our algorithm leverages a fast variational Bayes approximate inference methodology to scale to exome-wide analyses, a significant computational advantage over exact inference model selection methodologies. To demonstrate the efficacy of our methodology we test for associations between von Willebrand Factor (VWF) levels and VWF missense rare-variants imputed from the National Heart, Lung, and Blood Institute's Exome Sequencing project into 2,487 African Americans within the VWF gene. Our method suggests that a relatively small fraction (~10%) of the imputed rare missense variants within VWF are strongly associated with lower VWF levels in African Americans.

Risk of hearing loss among workers with vibration-induced white fingers.

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Pettersson, Hans; Burström, Lage; Hagberg, Mats; Lundström, Ronnie; Nilsson, Tohr

2014-12-01

We examined the risk of hearing loss for workers who use hand-held vibrating tools with vibration-induced white fingers (VWF) compared to workers without VWF. Data on 184 participants from a 21-year cohort were gathered with questionnaires and measurements. The effects on hearing status of VWF, hand-arm vibration exposure, smoking habits, age and two-way interactions of these independent variables were examined with binary logistic regression. Analyses were made for the right hand and ear as well as for the hand with VWF and the ear with worse categorized hearing status. Workers with VWF in their right hand had an increased risk of hearing loss (odds ratio 2.2-2.3) in the right ear. Workers with VWF in any hand did not have any increased risk of hearing loss in the ear with worse hearing status. This study supports the hypothesis that VWF increases the risk of hearing loss among workers who use hand-held vibrating tools in a noisy environment. © 2014 Wiley Periodicals, Inc.

Nitric oxide level and von Willebrand factor (vWF) secretion are not ...

African Journals Online (AJOL)

Jane

2011-08-15

Aug 15, 2011 ... potassium channels; RBECs, rat brain capillary endothelial cells. and transport of ... addition, adenine nucleotides modulate the release of endothelial-derive ..... A cellular model of endothelial cell ischemia. J Surg Res. 44(5): ...

Consumption of nattokinase is associated with reduced blood pressure and von Willebrand factor, a cardiovascular risk marker: results from a randomized, double-blind, placebo-controlled, multicenter North American clinical trial

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Jensen GS

2016-10-01

Full Text Available Gitte S Jensen,1 Miki Lenninger,1 Michael P Ero,2 Kathleen F Benson,1 1NIS Labs, Klamath Falls, OR, 2Machaon Diagnostics, Inc., Oakland, CA, USA Objective: The objective of this study is to evaluate the effects of consumption of nattokinase on hypertension in a North American hypertensive population with associated genetic, dietary, and lifestyle factors. This is in extension of, and contrast to, previous studies on Asian populations.Materials and methods: A randomized, double-blind, placebo-controlled, parallel-arm clinical study was performed to evaluate nattokinase (NSK-SD, a fermented soy extract nattō from which vitamin K2 has been removed. Based on the results from previous studies on Asian populations, 79 subjects were enrolled upon screening for elevated blood pressure (BP; systolic BP ≥130 or diastolic BP ≥90 mmHg who consumed placebo or 100 mg nattokinase/d for the 8-week study duration. Blood collections were performed at baseline and 8 weeks for testing plasma renin activity, von Willebrand factor (vWF, and platelet factor-4. Seventy-four people completed the study with good compliance.Results: Consumption of nattokinase was associated with a reduction in both systolic and diastolic BP. The reduction in systolic BP was seen for both sexes but was more robust in males consuming nattokinase. The average reduction in diastolic BP in the nattokinase group from 87 mmHg to 84 mmHg was statistically significant when compared to that in the group consuming placebo, where the average diastolic BP remained constant at 87 mmHg (P<0.05, and reached a high level of significance for males consuming nattokinase, where the average diastolic BP dropped from 86 mmHg to 81 mmHg (P<0.006. A decrease in vWF was seen in the female population consuming nattokinase (P<0.1. In the subpopulation with low plasma renin activity levels at baseline (<0.29 ng/mL/h, an increase was seen for 66% of the people after 8-week consumption of nattokinase (P

Labor management in a patient with on willebrand

International Nuclear Information System (INIS)

Saaqib, S.

2007-01-01

von Willebrand disease (VWD) is an inherited bleeding disorder involving a deficiency or abnormal function of a blood clotting protein called von Willebrand factor (VWF). Deficiency of VWF, therefore, shows primarily in organs with small blood vessels such as the skin, the gastrointestinal tract and the uterus. This case report describes management of a patient presenting with type II von Willebrand disease in labor. She had history of lifethreatening hemorrhage from an operation for deviated nasal septum and had a risk of severe postpartum hemorrhage (PPH) within 48 hours of delivery, which was avoided by appropriate planning and timely management. (author)

Circulating Endothelial Cells in Patients with Heart Failure and Left Ventricular Dysfunction

Science.gov (United States)

Martínez-Sales, Vicenta; Sánchez-Lázaro, Ignacio; Vila, Virtudes; Almenar, Luis; Contreras, Teresa; Reganon, Edelmiro

2011-01-01

Introduction and Aims: Acute and chronic heart failure may manifest different degrees of endothelial damage and angiogenesis. Circulating endothelial cells (CEC) have been identified as marker of vascular damage. The aim of our study was to evaluate the evolution of the CEC at different stages of patients with heart failure. We also investigated a potential correlation between CEC and markers of vascular damage and angiogenesis. Methods: We studied 32 heart failure patients at hospital admission (acute phase) and at revision after 3 months (stable phase) and 32 controls. Circulating markers of endothelial damage (CEC; von Willebrand factor, vWF and soluble E-selectin, sEsel) and angiogenesis (vascular endothelial growth factor, VEGF and thrombospondin-1) were quantified. Results: Levels of CEC, vWF, sEsel and VEGF are significantly higher in heart failure patients than in controls. Levels of CEC (36.9 ± 15.3 vs. 21.5 ± 10.0 cells/ml; p < 0.001), vWF (325 ± 101 vs. 231 ± 82%; p < 0.001) and VEGF (26.3 ± 15.2 vs. 21.9 ± 11.9 ng/ml; p < 0.001) are significantly higher in the acute phase than in the stable phase of heart failure. CEC levels correlate with vWF and VEGF. Results show than 100% of patients in acute phase and 37.5% in stable phase have levels of CEC higher than the 99th percentile of the distribution of controls (16 cells/ml). Therefore, increases in CEC represent a relative risk of 9.5 for heart failure patients suffering from acute phase. Conclusions: CEC, in addition to being elevated in heart failure, correlate with vWF levels, providing further support for CEC as markers of endothelial damage. Levels of CEC are associated with the acute phase of heart failure and could be used as a marker of the worsening in heart failure. PMID:21897001

Consumption of nattokinase is associated with reduced blood pressure and von Willebrand factor, a cardiovascular risk marker: results from a randomized, double-blind, placebo-controlled, multicenter North American clinical trial.

Science.gov (United States)

Jensen, Gitte S; Lenninger, Miki; Ero, Michael P; Benson, Kathleen F

2016-01-01

The objective of this study is to evaluate the effects of consumption of nattokinase on hypertension in a North American hypertensive population with associated genetic, dietary, and lifestyle factors. This is in extension of, and contrast to, previous studies on Asian populations. A randomized, double-blind, placebo-controlled, parallel-arm clinical study was performed to evaluate nattokinase (NSK-SD), a fermented soy extract nattō from which vitamin K2 has been removed. Based on the results from previous studies on Asian populations, 79 subjects were enrolled upon screening for elevated blood pressure (BP; systolic BP ≥130 or diastolic BP ≥90 mmHg) who consumed placebo or 100 mg nattokinase/d for the 8-week study duration. Blood collections were performed at baseline and 8 weeks for testing plasma renin activity, von Willebrand factor (vWF), and platelet factor-4. Seventy-four people completed the study with good compliance. Consumption of nattokinase was associated with a reduction in both systolic and diastolic BP. The reduction in systolic BP was seen for both sexes but was more robust in males consuming nattokinase. The average reduction in diastolic BP in the nattokinase group from 87 mmHg to 84 mmHg was statistically significant when compared to that in the group consuming placebo, where the average diastolic BP remained constant at 87 mmHg ( P nattokinase, where the average diastolic BP dropped from 86 mmHg to 81 mmHg ( P nattokinase ( P nattokinase ( P nattokinase consumption in a North American population is associated with beneficial changes to BP in a hypertensive population, indicating sex-specific mechanisms of action of nattokinase's effect on vWF and hypertension.

[Prevalence and risk factors of extra-coronary artery disease in patients with diabetes which confirmed atherosclerosis of coronary arteries].

Science.gov (United States)

Gracheva, S A; Biragova, M S; Glazunova, A M; Klefortova, I I; Melkozerov, K V; Shamkhalova, M Sh; Dzhavelidze, M I; Soldatova, T V; Il'in, A V; Deev, A D; Shestakova, M V; Tugeeva, E F; Buziashvili, Iu I

2014-01-01

To assess prevalence and risk factors of extra-coronary artery disease (peripheral artery (PA) disease (D) of lower extremities (LE), brachiocephalic arterial (BCA) stenosis (S), renal arterial (RA) S in type 1 and 2 (T1 and T2) diabetes (D) patients (P) with confirmed atherosclerosis of coronary arteries (CA). 100 P (48 with T2D, 18 with T1D, 34 without diabetes - PWD), with hemodynamically significant atherosclerosis of CA confirmed by coronary angiography. All patients underwent duplex ultrasonography of PA LE, BCA, RA. Other studies included assessment of clinical characteristics and measurement of the following parameters: profibrogenic cytokines (transforming growth factor [TGF] beta1, matrix metalloproteinase 9 [MMP9], monocyte chemotactic protein-1 [MCP-1], regulated on activation normal T-cell expressed and secreted [RANTES), markers of endothelial dysfunction (von Willebrand factor [VWF], homocystein [HCYST], plasminogen activator inhibitor-1 [PAI-1], vascular cell adhesion molecule [VCAM], soluble intercellular adhesion molecules-1 [sICAM], vascular endothelial growth factor [VEGF], asymmetric dimethylarginine [ADMAD, N-terminal fragment of pro-brain natriuretic peptide (NT-pro BNP), fibroblast growth factor 23 (FGF-23), and fibrinogen. Portions of P with multivessel CA disease were similar in all three groups (T1D - 88.9, T2D - 85.5, WD - 82.3%). Coexistence of atherosclerosis in 2 or more vascular beds was identified in 85.3% of T2D and in 50% of WD P (p = 0.005). In T1D group 61.1 and 11.1% of P had atherosclerosis in 2 and 3 vascular beds, respectively. Levels of profibrogenic cytokines and factors of endothelial activation (RANTES, MMP-9, PAI-I, VCAM, sICAM, ADMA) were significantly higher in P with diabetes vs P WD. P with diabetes and multifocal atherosclerosis demonstrated significant increases of CRP, fibrinogen, NT-proBNP, VWF, PAI-1, ADMA, sICAM, and decrease of GFR compared with P with atherosclerosis in 1 vascular bed. Logistic regression

Immunohistochemical expression of tenascin in melanocytic tumours of dogs.

Science.gov (United States)

Sevastre, B; van Ederen, A M; Terlou, M; Gruys, E; Nederbragt, H

2007-01-01

The aim of this study was to investigate tenascin-C (TN) immunolabelling and labelling for endothelium by von Willebrand Factor (vWF) in melanocytic tumours of dogs as compared with normal tissues, to evaluate the TN distribution in these types of tumours and to investigate whether a relation could be established between TN and angiogenesis in different types of tumour. Samples of normal dog skin (n=8), benign skin melanocytomas (n=10), malignant oral melanomas (n=9) and malignant toe melanomas (n=5) were studied. The percentages of TN and vWF immunolabelling per total microscopical area were analysed by morphometric methods. In normal skin, TN was found at dermo-epidermal junctions, around hair follicles, in the smooth muscles of hair follicles, and in the walls of blood vessels. TN immunolabelling (distribution and intensity) in melanocytomas was comparable with that found in normal skin. In melanomas, TN expression was considerably increased, its intensity in toe melanomas being twice that observed in oral melanomas. The degree of TN immunolabelling was not related to the histological malignancy of the melanomas. In melanomas, TN was found in the connective tissue surrounding the tumour cell nests and in narrow stromal strands inside the tumour. Regions infiltrated with lymphocytes were devoid of TN. The presence of TN around capillaries in melanocytomas and melanomas was investigated by double-immunolabelling (for TN and vWF). The intensity of vWF and TN immunolabelling was higher in melanomas than in melanocytomas, and higher in toe melanomas than in oral melanomas; however, no clear relation between TN expression and immunolabelling for vWF was found.

Von Willebrand's disease in the German shepherd dog : clinical communication

Directory of Open Access Journals (Sweden)

R.G. Lobetti

2000-07-01

Full Text Available Two litters of Germanshepherd dogs were evaluated for a haemorrhagic tendency that was characterised by excessive bleeding from the umbilicus at birth, haemorrhage and haematoma formation at vaccination, excessive bruising, and lameness due to haemarthrosis. Platelet counts, clotting times and Von Willebrand's factor (VWF assays were assessed in all dogs. Factor VIII determination was performed in 1 puppy and its parents. Based on the clotting times and VWF assay, 6 puppies (4 male and 2 female showed type I Von Willebrand's disease (VWD, 5 (4 male and 1 female possible type II VWD, and 4 were unaffected. One puppy with possible type II VWD had very low factor VIII activity; its sire had a normal factor activity, whereas the dam was in the low-normal range. This article reports type I and possible type II VWD in 2 related litters of German shepherd dogs, the latter being rare in German shepherd dogs.

Three months of strictly controlled daily endurance exercise reduces thrombin generation and fibrinolytic risk markers in younger moderately overweight men

DEFF Research Database (Denmark)

Gram, Anne Sofie; Bladbjerg, Else-Marie; Skov, Jane

2015-01-01

-PA), plasminogen activator inhibitor type 1 (PAI-1), and von Willebrand factor (vWF). RESULTS: We observed significant within-group decreases in ETP (MOD 7 %; HIGH 6 %) and in t-PA (MOD 22 %; HIGH 21 %) and PAI-1 (MOD 16 %; HIGH 32 %) in both training groups, and no changes in the CON group. At 3 months, between......-group differences were observed for ETP (p = 0.016) and t-PA (p = 0.012) due to significantly lower values in MOD and HIGH compared with CON. Borderline significant between-group differences were observed for PAI-1 (p = 0.082). A significant increase was observed in vWF in HIGH, but with no between...

Clinical and laboratory diagnosis of von Willebrand disease: A synopsis of the 2008 NHLBI/NIH guidelines

Science.gov (United States)

Nichols, William L.; Rick, Margaret E.; Ortel, Thomas L.; Montgomery, Robert R.; Sadler, J. Evan; Yawn, Barbara P.; James, Andra H.; Hultin, Mae B.; Manco-Johnson, Marilyn J.; Weinstein, Mark

2017-01-01

Von Willebrand factor (VWF) mediates blood platelet adhesion and accumulation at sites of blood vessel injury, and also carries coagulation factor VIII (FVIII) that is important for generating procoagulant activity. Von Willebrand disease (VWD), the most common inherited bleeding disorder, affects males and females, and reflects deficiency or defects of VWF that may also cause decreased FVIII. It may also occur less commonly as an acquired disorder (acquired von Willebrand syndrome). This article briefly summarizes selected features of the March 2008 evidence-based clinical and laboratory diagnostic recommendations from the National Heart, Lung, and Blood Institute (NHLBI) Expert Panel for assessment for VWD or other bleeding disorders or risks. Management of VWD is also addressed in the NHLBI guidelines, but is not summarized here. The VWD guidelines are available at the NHLBI Web site (http://www.nhlbi.nih.gov/guidelines/vwd). PMID:19415721

Expression, purification, and characterization of protective MPT64 antigen protein and identification of its multimers isolated from nontoxic Mycobacterium tuberculosis H37Ra.

Science.gov (United States)

Chu, Teng-Ping J; Yuann, Jeu-Ming P

2011-05-01

MPT64, a secreted protein of Mycobacterium tuberculosis (MTB), stimulates the immune reactions within cells and is a protective antigen that is lost by the bacilli Calmette-Guérin (BCG) vaccine during propagation. To minimize the toxicity caused by MTB, we used the MPT64 gene encoded by nontoxic H37Ra MTB to carry out genetic expansion via polymerase chain reaction and gene clone MPT64. The plasmid DNA encoded MPT64 was expressed at 20°C for 22 H, and a large quantity of MPT64 was obtained. In the absence of urea, MPT64 multimers with subunits being covalently connected via disulfide bonds were detected by Western blot showing strong protein-protein interactions, as evidenced by the formation of MPT64 tetramers. Finally, with urea of decreasing concentrations, we refolded MPT64 purified in the presence of urea and determined its secondary structures using circular dichroism. MPT64 was found to contain 2.2% α-helix, 50.9% β-sheet, 19.5% turn, and 27.4% random coil. The molecular weight of MPT64 was determined by a matrix-assisted laser desorption ionization-time of flight mass spectrometer and found to be 23,497 Da, very close to the theoretical molecular weight of MPT64. The results presented here provide a sound basis for future biochemical and biophysical studies of MPT64 or any other proteins encoded by nontoxic H37Ra MTB. Copyright © 2011 International Union of Biochemistry and Molecular Biology, Inc.

Endothelial markers in malignant vascular tumours of the liver: superiority of QB-END/10 over von Willebrand factor and Ulex europaeus agglutinin 1.

Science.gov (United States)

Anthony, P P; Ramani, P

1991-01-01

A new monoclonal antibody, QB-END/10, raised against the CD34 antigen in human endothelial cell membranes and haemopoietic progenitor cells, was studied for its usefulness as a marker of neoplastic vascular cells in 21 angiosarcomas and seven malignant haemangioendotheliomas of the liver. QB-END/10 was both more sensitive and more specific than Von Willebrand factor (VWF) and Ulex europaeus 1 agglutinin (UEA-1) in labelling endothelial cells and it did not cross react with epithelia as UEA-1 often does. Staining was uniformly strong and clear in all histological variants of these two tumours. QB-END/10 should prove particularly useful in the differential diagnosis of malignant vascular tumours of the liver.

Mechanism study of endothelial protection and inhibits platelet activation of low molecular weight fucoidan from Laminaria japonica

Science.gov (United States)

Chen, Anjin; Zhang, Fang; Shi, Jie; Zhao, Xue; Yan, Meixing

2016-10-01

Several studies have indicated that fucoidan fractions with low molecular weight and different sulfate content from Laminaria japonica could inhibit the activation of platelets directly by reducing the platelet aggregation. To explore the direct effect of LMW fucoidan on the platelet system furthermore and examine the possible mechanism, the endothelial protection and inhibits platelet activation effects of two LMW fucoidan were investigated. In the present study, Endothelial injury model of rats was made by injection of adrenaline (0.4 mg kg-1) and human umbilical vein endothelial cells were cultured. vWF level was be investigated in vivo and in vitro as an important index of endothelial injury. LMW fucoidan could significantly reduce vWF level in vascular endothelial injury rats and also significantly reduce vWF level in vitro. The number of EMPs was be detected as another important index of endothelial injury. The results showed that LMW fucoidan reduced EMPs stimulated by tumor necrosis factor. In this study, it was found that by inhibiting platelet adhesion, LMW fucoidan played a role in anti-thrombosis and the specific mechanism of action is to inhibit the flow of extracellular Ca2+. All in a word, LMW fucoidan could inhibit the activation of platelets indirectly by reducing the concentration of EMPs and vWF, at the same time; LMW fucoidan inhibited the activation of platelets directly by inhibiting the flow of extracellular Ca2+.

Noise-induced hearing loss and combined noise and vibration exposure.

Science.gov (United States)

Turcot, A; Girard, S A; Courteau, M; Baril, J; Larocque, R

2015-04-01

While there is a wide body of literature addressing noise-induced hearing loss (NIHL) and hand-arm vibration syndrome (HAVS) independently, relatively few studies have considered the combined effects of noise and vibration. These studies have suggested an increased risk of NIHL in workers with vibration white finger (VWF), though the relationship remains poorly understood. To determine whether hearing impairment is worse in noise-exposed workers with VWF than in workers with similar noise exposures but without VWF. The Quebec National Institute of Public Health audiometric database was used in conjunction with work-related accident and occupational diseases data from the Quebec workers' compensation board to analyse differences in audiometry results between vibration-exposed workers in the mining and forestry industries and the overall source population, and between mining and forestry workers with documented VWF and those without VWF. The International Organization for Standardization (ISO) 7029 standards were used to calculate hearing loss not attributable to age. 15751 vibration-exposed workers were identified in an overall source population of 59339. Workers with VWF (n = 96) had significantly worse hearing at every frequency studied (500, 1000, 2000 4000 Hz) compared with other mining and forestry workers without VWF. This study confirms previous findings of greater hearing loss at higher frequencies in workers with VWF, but also found a significant difference in hearing loss at low frequencies. It therefore supports the association between combined noise and hand-arm vibration (HAV) exposure and NIHL. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Biomarkers of endothelial dysfunction are elevated and related to prognosis in chronic heart failure patients with diabetes but not in those without diabetes

DEFF Research Database (Denmark)

Kistorp, C.; Chong, A.Y.; Gustafsson, F.

2008-01-01

Biomarkers of endothelial dysfunction, such as soluble E-selectin, and von Willebrand factor (vWf) are elevated in patients with chronic heart failure (CHF). The impact of diabetes mellitus (DM) on these biomarkers, and their relation to prognosis remains unknown....

Teoría de la carga cognitiva, diseño multimedia y aprendizaje: un estado del arte (Cognitive Load Theory, Design and Multimedia Learning: A State of the Art (Théorie de la charge cognitive, dessin multimédia et apprentissage: un état de l′art (Teoria da carga cognitiva, desenho multimídia e aprendizagem: um estado da arte

Directory of Open Access Journals (Sweden)

Luis Alejandro Andrade Lotero

2012-12-01

Full Text Available ResumenEn este artículo de revisión se presenta un resumen de la Teoría de la Carga Cognitiva y la Teoría Cognitiva del Aprendizaje Multimedia. Se dan algunos ejem- plos de investigaciones empíricas y se reflexiona acerca del valor explicativo de estas teorías del aprendizaje. Se exponen diez principios para el diseño de material instruccional. No obstante, otras investigaciones han encontrado limitaciones en el uso y práctica de estas teorías. Se refieren principalmente a la medición de la carga cognitiva, a la experiencia, al conocimiento previo de los aprendices y a la motivación y aspectos afectivos que intervienen en el proceso de aprendizaje.AbstractIn this review article is a summary of the Cognitive Load Theory and Cognitive Theory of Multimedia Lear- ning. Some examples of empirical research and considerations on the explanatory value of these learning theories are given, and ten principles for designing instructional material are shown. However, other research has found limitations in the use and practice of these theories. They mainly concern the measurement of cognitive load, experience and prior knowledge of the learners, as well as motivation and emotional aspects in- volved in the learning process.RésuméDans cet article de révision on pré- sente un résumé de la théorie de la charge cognitive et la théorie cogniti- ve de l'apprentissage multimédia. On fournit des exemples de recherches empiriques et on fait une réflexion par rapport à l'importance explica- tive de ces théories d’apprentissage. On présente dix principes pour le dessin du matériel d'instruction. Mal- gré les recherches qu'ont trouvé des limitations dans l'usage et la pratique de ces théories. Elles font référence, notamment à la mesure de la charge cognitive, à l'expérience et la con- naissance préalable des apprentis et aussi à la motivation et aux aspects affectifs qui intervient dans le pro- cessus de l

IMPACTO VISUAL NA IMPRENSA DIGITAL: uma pesquisa espanhola empírica

Directory of Open Access Journals (Sweden)

Joan Francesc Fondevila Gascón

2011-02-01

Full Text Available A inclusão da fonte visual (fotografia e vídeo no jornalismo digital
está ganhando importância na área da multimídia. Os recursos principais da imprensa digital são a multimídia, o hipertexto e a interatividade. A multimídia está num processo inicial de evolução. A missão desta pesquisa é observar empiricamente o uso dos recursos visuais pela imprensa digital pure player. Estes meios de comunicação tentam aproveitar as novas possibilidades multimídia na elaboração e apresentação dos conteúdos. Analisamos empiricamente a inclusão de vídeo e de fotografia na estrutura multimídia (texto, fotografia, vídeo, áudio, infografismo e programas de animação em quatro jornais digitais (Libertad Digital e El Plural, em espanhol, e Vilaweb.cat e e-Noticies, em catalão analisados por gêneros jornalísticos.

Spectroscopic properties of reaction center pigments in photosystem II core complexes: revision of the multimer model.

Science.gov (United States)

Raszewski, Grzegorz; Diner, Bruce A; Schlodder, Eberhard; Renger, Thomas

2008-07-01

Absorbance difference spectra associated with the light-induced formation of functional states in photosystem II core complexes from Thermosynechococcus elongatus and Synechocystis sp. PCC 6803 (e.g., P(+)Pheo(-),P(+)Q(A)(-),(3)P) are described quantitatively in the framework of exciton theory. In addition, effects are analyzed of site-directed mutations of D1-His(198), the axial ligand of the special-pair chlorophyll P(D1), and D1-Thr(179), an amino-acid residue nearest to the accessory chlorophyll Chl(D1), on the spectral properties of the reaction center pigments. Using pigment transition energies (site energies) determined previously from independent experiments on D1-D2-cytb559 complexes, good agreement between calculated and experimental spectra is obtained. The only difference in site energies of the reaction center pigments in D1-D2-cytb559 and photosystem II core complexes concerns Chl(D1). Compared to isolated reaction centers, the site energy of Chl(D1) is red-shifted by 4 nm and less inhomogeneously distributed in core complexes. The site energies cause primary electron transfer at cryogenic temperatures to be initiated by an excited state that is strongly localized on Chl(D1) rather than from a delocalized state as assumed in the previously described multimer model. This result is consistent with earlier experimental data on special-pair mutants and with our previous calculations on D1-D2-cytb559 complexes. The calculations show that at 5 K the lowest excited state of the reaction center is lower by approximately 10 nm than the low-energy exciton state of the two special-pair chlorophylls P(D1) and P(D2) which form an excitonic dimer. The experimental temperature dependence of the wild-type difference spectra can only be understood in this model if temperature-dependent site energies are assumed for Chl(D1) and P(D1), reducing the above energy gap from 10 to 6 nm upon increasing the temperature from 5 to 300 K. At physiological temperature, there are

Endothelial dysfunction, ambulatory pulse pressure and albuminuria are associated in Type 2 diabetic subjects

DEFF Research Database (Denmark)

Knudsen, Søren Tang; Jeppesen, Peter; Frederiksen, Christian Alcaraz

2007-01-01

as three urinary albumin/creatinine ratios. Von Willebrand factor (vWF), fibrinogen, E-selectin and soluble intercellular adhesion molecule 1 (ICAM-1) were measured in plasma. RESULTS: Thirty-four patients had normoalbuminuria (group N) and 12 had micro- or macroalbuminuria (group A). PP levels increased...

Influence of atrial fibrillation on plasma von willebrand factor, soluble E-selectin, and N-terminal pro B-type natriuretic peptide levels in systolic heart failure.

Science.gov (United States)

Freestone, Bethan; Gustafsson, Finn; Chong, Aun Yeong; Corell, Pernille; Kistorp, Caroline; Hildebrandt, Per; Lip, Gregory Y H

2008-05-01

Endothelial dysfunction is present in patients with heart failure (HF) due to left ventricular systolic dysfunction, as well as in patients with atrial fibrillation (AF) who have normal cardiac function. It is unknown whether AF influences the degree of endothelial dysfunction in patients with systolic HF. We measured levels of plasma von Willebrand factor (vWF) and E-selectin (as indexes of endothelial damage/dysfunction and endothelial activation, respectively; both enzyme-linked immunosorbent assay) in patients with AF and HF (AF-HF), who were compared to patients with sinus rhythm and HF (SR-HF), as well as in age-matched, healthy, control subjects. We also assessed the relationship of vWF and E-selectin to plasma N-terminal pro B-type natriuretic peptide (NTpro-BNP), a marker for HF severity and prognosis. One hundred ninety patients (73% men; mean age, 69.0 +/- 10.1 years [+/- SD]) with systolic HF were studied, who were compared to 117 healthy control subjects: 52 subjects (27%) were in AF, while 138 subjects (73%) were in sinus rhythm. AF-HF patients were older than SR-HF patients (p = 0.046), but left ventricular ejection fraction and New York Heart Association class were similar. There were significant differences in NT-proBNP (p NT-proBNP (p NT-proBNP levels (Spearman r = 0.139; p = 0.017). There is evidence of greater endothelial damage/dysfunction in AF-HF patients when compared to SR-HF patients. The clinical significance of this is unclear but may have prognostic value.

Histones link inflammation and thrombosis through the induction of Weibel-Palade body exocytosis.

Science.gov (United States)

Michels, A; Albánez, S; Mewburn, J; Nesbitt, K; Gould, T J; Liaw, P C; James, P D; Swystun, L L; Lillicrap, D

2016-11-01

Essentials Dysregulated DNA and histone release can promote pathological immunothrombosis. Weibel-Palade bodies (WPBs) are sentinel-like organelles that respond to proinflammatory stimuli. Histones induce WPB exocytosis in a caspase, calcium and charge-dependent mechanism. A targetable axis may exist between DNA/histones and WPBs in inflammation and immunothrombosis. Background Damage-associated molecular patterns (DAMPs), including molecules such as DNA and histones, are released into the blood following cell death. DAMPs promote a procoagulant phenotype through enhancement of thrombin generation and platelet activation, thereby contributing to immunothrombosis. Weibel-Palade bodies (WPBs) are dynamic endothelial cell organelles that contain procoagulant and proinflammatory mediators, such as von Willebrand factor (VWF), and are released in response to cell stresses. VWF mediates platelet adhesion and aggregation, and has been implicated as a procoagulant component of the innate immune response. Objective To determine the influence of histones and DNA on WPB release, and characterize their association in models of inflammation. Methods We treated C57BL/6J mice and cultured endothelial cells with histones (unfractionated, lysine-rich or arginine-rich) and DNA, and measured WPB exocytosis. We used inhibitors to determine a mechanism of histone-induced WPB release in vitro. We characterized the release of DAMPs and WPBs in response to acute and chronic inflammation in human and murine models. Results and conclusions Histones, but not DNA, induced the release of VWF (1.46-fold) from WBPs and caused thrombocytopenia (0.74-fold), which impaired arterial thrombus formation in mice. Histones induced WPB release from endothelial cells in a caspase-dependent, calcium-dependent and charge-dependent manner, and promoted platelet capture in a flow chamber model of VWF-platelet string formation. The levels of DAMPs and WPB-released proteins were elevated during inflammation

Responses of sympathetic nervous system to cold exposure in vibration syndrome subjects and age-matched healthy controls.

Science.gov (United States)

Nakamoto, M

1990-01-01

Plasma norepinephrine and epinephrine in vibration syndrome subjects and age-matched healthy controls were measured for the purpose of estimating the responsibility of the sympathetic nervous system to cold exposure. In preliminary experiment, it was confirmed that cold air exposure of the whole body was more suitable than one-hand immersion in cold water. In the main experiment, 195 subjects were examined. Sixty-five subjects had vibration syndrome with vibration-induced white finger (VWF + group) and 65 subjects had vibration syndrome without VWF (VWF- group) and 65 controls had no symptoms (control group). In the three groups, plasma norepinephrine levels increased during cold air exposure of whole body at 7 degrees +/- 1.5 degrees C. Blood pressure increased and skin temperature decreased during cold exposure. Percent increase of norepinephrine in the VWF+ group was the highest while that in VWF- group followed and that in the control group was the lowest. This whole-body response of the sympathetic nervous system to cold conditions reflected the VWF which are characteristic symptoms of vibration syndrome. Excluding the effects of shivering and a cold feeling under cold conditions, it was confirmed that the sympathetic nervous system in vibration syndrome is activated more than in the controls. These results suggest that vibration exposure to hand and arm affects the sympathetic nervous system.

Relationships of inflammatory and haemostatic markers with social class: results from a population-based study of older men.

Science.gov (United States)

Ramsay, Sheena; Lowe, Gordon D O; Whincup, Peter H; Rumley, Ann; Morris, Richard W; Wannamethee, S Goya

2008-04-01

Haemostatic and inflammatory markers have been hypothesised to mediate the relationship of social class and cardiovascular disease (CVD). We investigated whether a range of inflammatory/haemostatic markers are associated with social class independent of chronic diseases and behavioural risk factors in a population-based sample of 2682 British men aged 60-79 without a physician diagnosis of CVD, diabetes or musculoskeletal disease requiring anti-inflammatory medications. Men in lower social classes had higher mean levels of C-reactive protein, fibrinogen, interleukin-6, white blood cell count, von Willebrand factor (vWF), factor VIII, activated protein C (APC) resistance, plasma viscosity, fibrin D-dimer and platelet count, compared to higher social class groups; but not of tissue plasminogen activator antigen, haematocrit or activated partial prothrombin time. After adjustment for behavioural risk factors (smoking, alcohol, physical activity and body mass), the associations of social class with vWF, factor VIII, APC resistance, plasma viscosity, and platelet count though weakened, remained statistically significant, while those of other markers were considerably attenuated. In this study of older men without CVD, the social gradient in inflammatory and haemostatic markers was substantially explained by behavioural risk factors. The effect of socio-economic gradient on the factor VIII-vWF complex, APC resistance, plasma viscosity and platelet count merits further study.

A case of refractory thrombotic thrombocytopenic purpura treated ...

African Journals Online (AJOL)

Background. Thrombotic thrombocytopenic purpura (TTP) is a rare, life-threaten- ing disorder that occurs due to deficiency of ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member. 13), which is a von Willebrand factor (VWF) cleaving protein.[1]. The absent or severely reduced activity ...

Platelets in thrombosis and hemostasis: old topic with new mechanisms.

Science.gov (United States)

Wang, Yiming; Andrews, Marc; Yang, Yan; Lang, Sean; Jin, Joseph W; Cameron-Vendrig, Alison; Zhu, Guangheng; Reheman, Adili; Ni, Heyu

2012-12-01

Platelets are small anucleate cells generated from megakaryocytes in the bone marrow. After being released into the circulation, platelets play key roles in the surveillance of vascular injury, and can quickly adhere and aggregate at the site of injury, which are critical events for vascular repair and hemostasis. However, the same biological processes of platelet adhesion and aggregation may also cause thrombotic disorders. The formation of a platelet plug at sites of atherosclerotic lesion rupture is the most common mechanism leading to myocardial or cerebral infarction. Platelet-related deep vein thrombosis is also one of the leading causes of mortality worldwide. The contribution of several platelet receptors and their ligands has been highlighted in these processes. In platelet adhesion, particularly at high shear stress, GPIbα-von Willebrand factor (VWF) interaction may initiate this event, which is followed by GPVI signalling and firm platelet adhesion mediated by members of the integrin family, such as β3 (αIIbβ3) and β1 (α2β1, α5β1) integrins. In platelet aggregation, although GPIbα-VWF, P selectin-sulfatides, and other molecules, may be involved, the process is mainly mediated by β3 (αIIbβ3) integrin and its ligands, such as fibrinogen and VWF. It is intriguing that platelet adhesion and aggregation still occur in mice lacking both fibrinogen and VWF, suggesting that other unforeseen molecule(s) may also be important in these processes. Identification and characterization of these molecules will enrich our knowledge in the basic science of hemostasis and thrombosis, and may lead to the development of new therapies against bleeding disorders and thrombotic diseases.

Sirtuin1 single nucleotide polymorphism (A2191G is a diagnostic marker for vibration-induced white finger disease

Directory of Open Access Journals (Sweden)

Voelter-Mahlknecht Susanne

2012-10-01

Full Text Available Abstract Background Vibration-induced white finger disease (VWF, also known as hand-arm vibration syndrome, is a secondary form of Raynaud’s disease, affecting the blood vessels and nerves. So far, little is known about the pathogenesisof the disease. VWF is associated with an episodic reduction in peripheral blood flow. Sirtuin 1, a class III histone deacetylase, has been described to regulate the endothelium dependent vasodilation by targeting endothelial nitric oxide synthase. We assessed Sirt1single nucleotide polymorphisms in patients with VWF to further elucidate the role of sirtuin 1 in the pathogenesis of VWF. Methods Peripheral blood samples were obtained from 74 patients with VWF (male 93.2%, female 6.8%, median age 53 years and from 317 healthy volunteers (gender equally distributed, below 30 years of age. Genomic DNA was extracted from peripheral blood mononuclear cells and screened for potential Sirt1single nucleotide polymorphisms. Four putative genetic polymorphisms out of 113 within the Sirt1 genomic region (NCBI Gene Reference: NM_012238.3 were assessed. Allelic discrimination was performed by TaqMan-polymerasechainreaction-based allele-specific genotyping single nucleotide polymorphism assays. Results Sirt1single nucleotide polymorphism A2191G (Assay C_25611590_10, rs35224060 was identified within Sirt1 exon 9 (amino acid position 731, Ile → Val, with differing allelic frequencies in the VWF population (A/A: 70.5%, A/G: 29.5%, G/G: 0% and the control population (A/A: 99.7%, A/G: 0.3%, G/G: 0.5%, with significance levels of P U test (two-tailed P t-test and Chi-square test with Yates correction (all two-tailed: P Conclusion We identified theSirt1A2191Gsingle nucleotide polymorphism as a diagnostic marker for VWF.

Early intraoperative blood collection does not affect complete blood counts, von Willebrand factor or factor VIII levels in normal children.

Science.gov (United States)

Darwish, Hanni; Mundell, Gillianne; Engen, Dale; Lillicrap, David; Silva, Mariana; James, Paula

2011-01-01

Obtaining blood from children for research studies can be difficult, particularly for controls. One solution is to obtain samples during elective surgery; however, consideration must be given to the potential effects of the timing of phlebotomy. Ten children were recruited and phlebotomy was carried out during a preoperative clinic visit and intraoperatively immediately after the induction of anesthesia but before the start of surgery. CBCs, VWF, and FVIII levels were measured at both time points and no significant differences were seen. This negative result may be beneficial to pediatric research by suggesting that early intraoperative blood collection for controls does not affect the results.

Thrombin Generating Capacity and Phenotypic Association in ABO Blood Groups.

Science.gov (United States)

Kremers, Romy M W; Mohamed, Abdulrahman B O; Pelkmans, Leonie; Hindawi, Salwa; Hemker, H Coenraad; de Laat, H Bas; Huskens, Dana; Al Dieri, Raed

2015-01-01

Individuals with blood group O have a higher bleeding risk than non-O blood groups. This could be explained by the lower levels of FVIII and von Willebrand Factor (VWF) levels in O individuals. We investigated the relationship between blood groups, thrombin generation (TG), prothrombin activation and thrombin inactivation. Plasma levels of VWF, FVIII, antithrombin, fibrinogen, prothrombin and α2Macroglobulin (α2M) levels were determined. TG was measured in platelet rich (PRP) and platelet poor plasma (PPP) of 217 healthy donors and prothrombin conversion and thrombin inactivation were calculated. VWF and FVIII levels were lower (75% and 78%) and α2M levels were higher (125%) in the O group. TG is 10% lower in the O group in PPP and PRP. Less prothrombin was converted in the O group (86%) and the thrombin decay capacity was lower as well. In the O group, α2M plays a significantly larger role in the inhibition of thrombin (126%). In conclusion, TG is lower in the O group due to lower prothrombin conversion, and a larger contribution of α2M to thrombin inactivation. The former is unrelated to platelet function because it is similar in PRP and PPP, but can be explained by the lower levels of FVIII.

Optimisation of the Factor VIII yield in mammalian cell cultures by reducing the membrane bound fraction

DEFF Research Database (Denmark)

Kolind, Mille Petersen; Nørby, Peder Lisby; Berchtold, Martin Werner

2011-01-01

and forms the tenase complex together with clotting Factor IX. In vitro, during serum free production of recombinant FVIII (rFVIII), production cells also expose PS, and since vWF is not present to hinder interaction of secreted rFVIII with PS, rFVIII is partly associated with the cell membrane...... of active membrane bound rFVIII to the culture medium. Moreover, the attachment of rFVIII to cell membranes of un-transfected HEK293 cells was studied in the presence of compounds that competes for interactions between rFVIII and PS. Competitive assays between iodinated rFVIII (¹²5I-rFVIII) and annexin V...... or ortho-phospho-L-serine (OPLS) demonstrated that annexin V and OPLS were able to reduce the membrane bound fraction of rFVIII by 70% and 30%, respectively. Finally, adding OPLS to CHO cells stably expressing FVIII increased the yield by 50%. Using this new knowledge, the recovery of rFVIII could...

Effects of virtual water flow on regional water resources stress: A case study of grain in China.

Science.gov (United States)

Sun, Shikun; Wang, Yubao; Engel, Bernie A; Wu, Pute

2016-04-15

Scarcity of water resources is one of the major challenges in the world, particularly for the main water consumer, agriculture. Virtual water flow (VWF) promotes water redistribution geographically and provides a new solution for resolving regional water shortage and improving water use efficiency in the world. Virtual water transfer among regions will have a significant influence on the water systems in both grain export and import regions. In order to assess the impacts of VWF related grain transfer on regional water resources conditions, the study takes mainland China as study area for a comprehensive evaluation of virtual water flow on regional water resources stress. Results show that Northeast China and Huang-Huai-Hai region are the major grain production regions as well as the major virtual water export regions. National water savings related to grain VWF was about 58Gm(3), with 48Gm(3) blue water and 10Gm(3) green water. VWF changes the original water distribution and has a significant effect on water resources in both virtual water import and export regions. Grain VWF significantly increased water stress in grain export regions and alleviated water stress in grain import regions. Water stress index (WSI) of Heilongjiang and Inner Mongolia has been increased by 138% and 129% due to grain export. Stress from water shortages is generally severe in export regions, and issues with the sustainability of grain production and VWF pattern are worthy of further exploration. Copyright © 2016 Elsevier B.V. All rights reserved.

Mechanical Dissociation of Platelet Aggregates in Blood Stream

Science.gov (United States)

Hoore, Masoud; Fedosov, Dmitry A.; Gompper, Gerhard; Complex; Biological Fluids Group Team

2017-11-01

von Willebrand factor (VWF) and platelet aggregation is a key phenomenon in blood clotting. These aggregates form critically in high shear rates and dissolve reversibly in low shear rates. The emergence of a critical shear rate, beyond which aggregates form and below which they dissolve, has an interesting impact on aggregation in blood flow. As red blood cells (RBCs) migrate to the center of the vessel in blood flow, a RBC free layer (RBC-FL) is left close to the walls into which the platelets and VWFs are pushed back from the bulk flow. This margination process provides maximal VWF-platelet aggregation probability in the RBC-FL. Using mesoscale hydrodynamic simulations of aggregate dynamics in blood flow, it is shown that the aggregates form and grow in RBC-FL wherein shear rate is high for VWF stretching. By growing, the aggregates penetrate to the bulk flow and get under order of magnitude lower shear rates. Consequently, they dissolve and get back into the RBC-FL. This mechanical limitation for aggregates prohibits undesired thrombosis and vessel blockage by aggregates, while letting the VWFs and platelets to aggregate close to the walls where they are actually needed. The support by the DFG Research Unit FOR 1543 SHENC and CPU time Grant by the Julich Supercomputing Center are acknowledged.

Évaluer l'impact des stéréotypes dans les supports multimédia Evaluating the impact of stereotypes in multimedia tools

Directory of Open Access Journals (Sweden)

Joëlle Aden

2006-12-01

Full Text Available La navigation sur Internet offre aux enseignants de langues vivantes un kaléidoscope de supports authentiques variés, qui reflète des points de vues multi perspectivistes sur les réalités socioculturelles des groupes qui utilisent la langue apprise. La navigation est probablement un des usages du multimédia les plus développés dans l'enseignement de masse en langues. Il suffit, pour s'en convaincre, de parcourir les méthodes éditées ces cinq dernières années pour voir que l'outil multimédia est surtout sollicité pour faire des recherches sur des thèmes étudiés en classe et de nombreux travaux ont mis en avant le potentiel de cet outil. Dans les classes, l'idée selon laquelle il est indispensable de laisser les élèves naviguer sans guidage dans l'hypertexte a très vite cédé la place à la nécessité de réduire l'accès aux ressources Internet à l'intérieur de cadres contraints, en général à partir de sites présélectionnés à cet effet en vue de réaliser des tâches dans la langue d'étude. Aujourd'hui, dans la formation en langue des enseignants, deux types de dispositifs Tice (technologies de l'information et de la communication pour l'éducation occupent la première place : les cyberenquêtes (webquests et les échanges par courrier électronique, mais à nouveau, les limites des cyberenquêtes sont perceptibles, elles recréent des contraintes formelles dans lesquelles on force les repérages. Dans cet article, nous nous intéresserons à un dispositif[1] intégrant des activités plus libres de navigation et de choix de supports vidéo que nous avons réintégré dans une démarche culturelle en classe. Nous considérerons la façon dont la variété de ces supports, libres et contraints, influe sur la construction des repères identitaires des élèves. Nous étudierons ce phénomène en lien avec les mécanismes cognitifs et socio discursifs que les apprenants mettent en œuvre lorsqu'ils sont exposés �

Pseudo (Platelet-type von Willebrand disease in pregnancy: a case report

Directory of Open Access Journals (Sweden)

Grover Neetu

2013-01-01

Full Text Available Abstract Background Pseudo (platelet-type-von Willebrand disease is a rare autosomal dominant bleeding disorder caused by an abnormal function of the glycoprotein lb protein; the receptor for von Willebrand factor. This leads to an increased removal of VWF multimers from the circulation as well as platelets and this results in a bleeding diathesis. Worldwide, less than 50 patients are reported with platelet type von Willebrand disease (PT-VWD. Case presentation We describe the management of platelet type von Willebrand disease in pregnancy of a 26 year old Caucasian primigravida. The initial diagnosis was made earlier following a significant haemorrhage post tonsillectomy several years prior to pregnancy. The patient was managed under a multidisciplinary team which included obstetricians, haematologists, anaesthetists and neonatologists. Care plans were made for the ante- natal, intra-partum and post-partum periods in partnership with the patient. The patient’s platelet count levels dropped significantly during the antenatal period. This necessitated the active exclusion of other causes of thrombocytopenia in pregnancy. A vaginal delivery was desired and plans were made for induction of labour at 38 weeks of gestation with platelet cover in view of the progressive fall of the platelet count. The patient however went into spontaneous labour on the day of induction. She was transfused two units of platelets before delivery. She had an unassisted vaginal delivery of a healthy baby. The successful antenatal counselling has encouraged the diagnosis of the same condition in her mother and sister. We found this to be a particularly interesting case as well as challenging to manage due to its rarity. Psuedo von Willebrand disease in pregnancy can be confused with a number of other differential diagnoses, such as gestational thrombocutopenia, idiopathatic thrombocytopenia, thrombotic thrombocytopenic purpura and pre-eclampsia; all need consideration

Ayurgenomics: Understanding human individuality through ...

Indian Academy of Sciences (India)

mitali

Knowledge. VATA. PITTA. KAPHA. Stratification of Healthy based on prakriti. Axes of variation in Prakriti. EGLN1-HIF axis in. HAA/HAPE/asthma. Hypoxia responsiveness. (EGLN1 –HIF1-vWF). Hypoxia axis differentially regulated in VADU cohort. Hypoxia and Hemostasis axes linked through Prakriti. VWF levels also differ.

Platelet aggregation, secretion, and coagulation changes in children with asthma.

Science.gov (United States)

Buyukyilmaz, Gonul; Soyer, Ozge U; Buyuktiryaki, Betul; Alioglu, Bulent; Dallar, Yildiz

2014-10-01

The chronic inflammation in asthma evolves by cells including eosinophils, mast cells and lymphocytes. Despite their principal function in hemostasis, platelets contribute to pathogenesis of asthma that activation of platelets occurs following antigen provocation and during asthma attack. Our aim was to evaluate the platelet functions and other hemostatic features of children with asthma, both during symptom-free period and asthma attack. We enrolled patients with asthma attack (n = 33), mild intermittent asthma (n = 18), mild persistent asthma (n = 15) and healthy children (n = 20). Demographic characteristics and disease-related features were noted. Platelet aggregation and secretion tests (expressed as ATP release) were performed by lumiaggregometer method by stimulation with collagen, epinephrine, ADP, thrombin, ristocetin and arachidonic acid. Plasma levels of D-dimer, factor VIII (FVIII) and von Willebrand factor (vWF) were assessed. There were no differences in platelet aggregation induced by agonists between study groups. ATP release from platelets of patients with asthma exacerbation induced by ADP was lower compared with mild intermittent asthma (P asthma attack than mild intermittent (P = 0.039) and mild persistent asthma (P = 0.011) and controls (P = 0.018). vWF measurements were higher in children with asthma attack than other study groups (P = 0.001). However, FVIII was increased in patients with severe asthma attack. Asthma is a disease in which many immune cells play a role, one of which is the platelet. Distinctions in platelet secretion profiles and plasma levels of vWF and FVIII provide evidence that coagulation mechanisms might be critical for asthma pathogenesis.

Monomer-dimer control of the ColE1 P(cer) promoter.

Science.gov (United States)

Chatwin, H M; Summers, D K

2001-11-01

XerCD-mediated recombination at cer converts multimers of plasmid ColE1 to monomers, maximizing the number of independently segregating molecules and minimizing the frequency of plasmid loss. In addition to XerCD, recombination requires the accessory factors ArgR and PepA. The promoter P(cer), located centrally within cer, is also required for stable plasmid maintenance. P(cer) is active in plasmid multimers and directs transcription of a short RNA, Rcd, which appears to inhibit cell division. It has been proposed that Rcd is part of a checkpoint which ensures that multimer resolution is complete before the cell divides. This study has shown that ArgR does not act as a transcriptional repressor of P(cer) in plasmid monomers. P(cer) is unusual in that the -35 and -10 hexamers are separated by only 15 bp and this study has demonstrated that increasing this to a more conventional spacing results in elevated activity. An increase to 17 bp resulted in a 10- to 20-fold increase in activity, while smaller effects were seen when the spacer was increased to 16 bp or 18 bp. These observations are consistent with the hypothesis that P(cer) activation involves realignment of the -35 and -10 sequences within a recombinational synaptic complex. This predicts that a 17 bp spacer promoter derivative should be down-regulated by plasmid multimerization, and this is confirmed experimentally.

Multimer Formation Explains Allelic Suppression of PRDM9 Recombination Hotspots

Czech Academy of Sciences Publication Activity Database

Baker, C.L.; Petkova, P.; Walker, M.; Flachs, Petr; Mihola, Ondřej; Trachtulec, Zdeněk; Petkov, P.M.; Paigen, K.

2015-01-01

Roč. 11, č. 9 (2015), e1005512-e1005512 ISSN 1553-7390 R&D Projects: GA ČR GAP305/10/1931; GA ČR(CZ) GA14-20728S; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:68378050 Keywords : recombination * PRDM9 * allelic competition Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 7.528, year: 2014

Radioimmunoassay for platelet activation specific protein GMP-140 on the platelet surface and in plasma

International Nuclear Information System (INIS)

Wu Guoxin; Li Jianyong; Ruan Changgeng

1991-08-01

Using monoclonal antibody (McAb) SZ-51 which is specific for an alpha-granule membrane protein (GMP-140) on the surface of human activated platelets, the platelet GMP-140 expression in fixed whole blood was measured by direct radioimmunoassay and GMP-140 microparticles in plasma was measured by sandwich method. The GMP-140 molecules per platelet or milliliter (mL) were calculated for the following subjects; acute myocardial infarction; cerebro thrombosis; diabetic mellitus; asthma attack; epidemic hemorrhagic fever etc.. By comparing with the concentration of thromboxane B 2 (TXB 2 ) and von Willebrand factor (vWF) in plasma, it is confirmed that the measurement of GMP-140 molecules is better than that of TXB 2 and vWF. It is a sensitive and specific method for evaluating the platelet activation degree in vivo. The establishment of this method will be useful to diagnosing the thrombotic disorders and studying the pathogenesis of some other diseases

Thrombus Formation at High Shear Rates.

Science.gov (United States)

Casa, Lauren D C; Ku, David N

2017-06-21

The final common pathway in myocardial infarction and ischemic stroke is occlusion of blood flow from a thrombus forming under high shear rates in arteries. A high-shear thrombus forms rapidly and is distinct from the slow formation of coagulation that occurs in stagnant blood. Thrombosis at high shear rates depends primarily on the long protein von Willebrand factor (vWF) and platelets, with hemodynamics playing an important role in each stage of thrombus formation, including vWF binding, platelet adhesion, platelet activation, and rapid thrombus growth. The prediction of high-shear thrombosis is a major area of biofluid mechanics in which point-of-care testing and computational modeling are promising future directions for clinically relevant research. Further research in this area will enable identification of patients at high risk for arterial thrombosis, improve prevention and treatment based on shear-dependent biological mechanisms, and improve blood-contacting device design to reduce thrombosis risk.

Effect of continuous positive airway pressure ventilation on prethrombotic state in patients with obstructive sleep apnea-hypopnea syndrome

International Nuclear Information System (INIS)

Guo Dianbao; Chen Xiangkun; Sheng Chunyong; Zhang Yingying

2009-01-01

To investigate the prethrombotic state (PTS) in patients with obstructive sleep apnea syndrome (OS-AS) and the effect of continuous positive airway pressure ventilation (CPAP) on their PTS, the blood samples of 49 patients with OSAS were taken before treatment and on day 30 after treatment respectively. The platelet aggregation ( PAG), P-selections, endothdlin-1 (ET-1) and plasma vom willebrand factor (vWF) in 49 patients and 42 health controls were detected by radioimmunoassay and enzyme-immunoassay. The results showed that the PAG, P-selections, ET-1 and vWF in patients with OSAS before treatment were significantly higher than those after treatment and in control group (P 0.05). The results indicate that there were PTS in most patients with OSAS before treatment. The activity of platelet could be corrected, and the function of endotheliocyte could be repaired after CPAP treatment. It had certain effect in lightening the clinical symptoms. (authors)

Development, validation and application of a micro-liquid chromatography-tandem mass spectrometry based method for simultaneous quantification of selected protein biomarkers of endothelial dysfunction in murine plasma.

Science.gov (United States)

Suraj, Joanna; Kurpińska, Anna; Olkowicz, Mariola; Niedzielska-Andres, Ewa; Smolik, Magdalena; Zakrzewska, Agnieszka; Jasztal, Agnieszka; Sitek, Barbara; Chlopicki, Stefan; Walczak, Maria

2018-02-05

The objective of this study was to develop and validate the method based on micro-liquid chromatography-tandem mass spectrometry (microLC/MS-MRM) for simultaneous determination of adiponectin (ADN), von Willebrand factor (vWF), soluble form of vascular cell adhesion molecule 1 (sVCAM-1), soluble form of intercellular adhesion molecule 1 (sICAM-1) and syndecan-1 (SDC-1) in mouse plasma. The calibration range was established from 2.5pmol/mL to 5000pmol/mL for ADN; 5pmol/mL to 5000pmol/mL for vWF; 0.375pmol/mL to 250pmol/mL for sVCAM-1 and sICAM-1; and 0.25pmol/mL to 250pmol/mL for SDC-1. The method was applied to measure the plasma concentration of selected proteins in mice fed high-fat diet (HFD), and revealed the pro-thrombotic status by increased concentration of vWF (1.31±0.17 nmol/mL (Control) vs 1.98±0.09 nmol/mL (HFD), p <0.05) and the dysregulation of adipose tissue metabolism by decreased concentration of ADN (0.62±0.08 nmol/mL (Control) vs 0.37±0.06 nmol/mL (HFD), p <0.05). In conclusion, the microLC/MS-MRM-based method allows for reliable measurements of selected protein biomarkers of endothelial dysfunction in mouse plasma. Copyright © 2017 Elsevier B.V. All rights reserved.

Biomarkers of drug-induced vascular injury

International Nuclear Information System (INIS)

Brott, D.; Gould, S.; Jones, H.; Schofield, J.; Prior, H.; Valentin, J.P; Bjurstrom, S.; Kenne, K.; Schuppe-Koistinen, I.; Katein, A.; Foster-Brown, L.; Betton, G.; Richardson, R.; Evans, G.; Louden, C.

2005-01-01

In pre-clinical safety studies, drug-induced vascular injury is an issue of concern because there are no obvious diagnostic markers for pre-clinical or clinical monitoring and there is an intellectual gap in our understanding of the pathogenesis of this lesion. While vasodilatation and increased shear stress appear to play a role, the exact mechanism(s) of injury to the primary targets, smooth muscle and endothelial cells are unknown. However, evaluation of novel markers for potential clinical monitoring with a mechanistic underpinning would add value in risk assessment and management. This mini review focuses on the progress to identify diagnostic markers of drug-induced vascular injury. Von Willebrand factor (vWF), released upon perturbation of endothelial cells, is transiently increased in plasma prior to morphological evidence of damage in dogs or rats treated with vascular toxicants. Therefore, vWF might be a predictive biomarker of vascular injury. However, vWF is not an appropriate biomarker of lesion progression or severity since levels return to baseline values when there is morphological evidence of injury. A potential mechanistically linked biomarker of vascular injury is caveolin-1. Expression of this protein, localized primarily to smooth muscle and endothelial cells, decreases with the onset of vascular damage. Since vascular injury involves multiple mediators and cell types, evaluation of a panel rather than a single biomarker may be more useful in monitoring early and severe progressive vascular injury

INCREASED VASOOCCLUSIVE CRISIS IN “O” BLOOD GROUP SICKLE CELL DISEASE PATIENTS: ASSOCIATION WITH UNDERLYING THROMBOSPONDIN LEVELS.

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M. Al Huneini

2017-04-01

Full Text Available Abstract: Objectives: To explore the incidence of vaso-occlusive crisis (VOC in Blood Group “O” sickle cell disease (SCD patients, and correlate it with the blood group and thrombospondin (TSP levels. Methods: In 89 consecutive SCD patients, blood samples were obtained for vWF antigen, collagen binding activity, blood group typing, C-reactive protein, variant hemoglobin analysis (HPLC, Serum TSP 1 and TSP 2 levels, complete blood counts, liver function tests, LDH and renal function tests during VOC episodes and in steady state conditions. Results: In the steady state SCD patients (n=72, “O” blood group patients (n=37 showed significantly higher median serum TSP 1 and TSP 2 levels than the non “O” blood group patients [n=35] [p <0.05, Mann-Whitney test], with an inverse relation between VWF:Ag, Factor VIII:C and TSP levels. Furthermore, the serum TSP 1 and TSP 2 levels were significantly higher in patients presenting with acute VOC [n=17], and in those with repeated VOC’s (group 1, n=16 especially amongst those patients with blood group “O” [p, <0.05, Mann-Whitney test]. Conclusions: The study shows that there was an inverse relation between TSP and vWF levels, in blood group “O” SCD patients with an upregulation of the TSP levels. Expectedly, during active VOC crisis, the TSP 1 and TSP 2 levels were significantly elevated.    Key Words: VOC; SCD; TSP; vWD; Blood groups

High-affinity, noninhibitory pathogenic C1 domain antibodies are present in patients with hemophilia A and inhibitors

Science.gov (United States)

Batsuli, Glaivy; Deng, Wei; Healey, John F.; Parker, Ernest T.; Baldwin, W. Hunter; Cox, Courtney; Nguyen, Brenda; Kahle, Joerg; Königs, Christoph; Li, Renhao; Lollar, Pete

2016-01-01

Inhibitor formation in hemophilia A is the most feared treatment-related complication of factor VIII (fVIII) therapy. Most inhibitor patients with hemophilia A develop antibodies against the fVIII A2 and C2 domains. Recent evidence demonstrates that the C1 domain contributes to the inhibitor response. Inhibitory anti-C1 monoclonal antibodies (mAbs) have been identified that bind to putative phospholipid and von Willebrand factor (VWF) binding epitopes and block endocytosis of fVIII by antigen presenting cells. We now demonstrate by competitive enzyme-linked immunosorbent assay and hydrogen-deuterium exchange mass spectrometry that 7 of 9 anti-human C1 mAbs tested recognize an epitope distinct from the C1 phospholipid binding site. These mAbs, designated group A, display high binding affinities for fVIII, weakly inhibit fVIII procoagulant activity, poorly inhibit fVIII binding to phospholipid, and exhibit heterogeneity with respect to blocking fVIII binding to VWF. Another mAb, designated group B, inhibits fVIII procoagulant activity, fVIII binding to VWF and phospholipid, fVIIIa incorporation into the intrinsic Xase complex, thrombin generation in plasma, and fVIII uptake by dendritic cells. Group A and B epitopes are distinct from the epitope recognized by the canonical, human-derived inhibitory anti-C1 mAb, KM33, whose epitope overlaps both groups A and B. Antibodies recognizing group A and B epitopes are present in inhibitor plasmas from patients with hemophilia A. Additionally, group A and B mAbs increase fVIII clearance and are pathogenic in a hemophilia A mouse tail snip bleeding model. Group A anti-C1 mAbs represent the first identification of pathogenic, weakly inhibitory antibodies that increase fVIII clearance. PMID:27381905

25-Hydroxyvitamin D and pre-clinical alterations in inflammatory and hemostatic markers: a cross sectional analysis in the 1958 British Birth Cohort.

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Elina Hyppönen

Full Text Available BACKGROUND: Vitamin D deficiency has been suggested as a cardiovascular risk factor, but little is known about underlying mechanisms or associations with inflammatory or hemostatic markers. Our aim was to investigate the association between 25-hydroxyvitamin D [25(OHD, a measure for vitamin D status] concentrations with pre-clinical variations in markers of inflammation and hemostasis. METHODOLOGY/PRINCIPAL FINDINGS: Serum concentrations of 25(OHD, C-reactive protein (CRP, fibrinogen, D-dimer, tissue plasminogen activator (tPA antigen, and von Willebrand factor (vWF were measured in a large population based study of British whites (aged 45 y. Participants for the current investigation were restricted to individuals free of drug treated cardiovascular disease (n = 6538. Adjusted for sex and month, 25(OHD was inversely associated with all outcomes (p or =75 nmol/l compared to < 25 nmol/l. D-dimer concentrations were lower for participants with 25(OHD 50-90 nmol/l compared to others (quadratic term p = 0.01. We also examined seasonal variation in hemostatic and inflammatory markers, and evaluated 25(OHD contribution to the observed patterns using mediation models. TPA concentrations varied by season (p = 0.02, and much of this pattern was related to fluctuations in 25(OHD concentrations (p < or =0.001. Some evidence of a seasonal variation was observed also for fibrinogen, D-dimer and vWF (p < 0.05 for all, with 25(OHD mediating some of the pattern for fibrinogen and D-dimer, but not vWF. CONCLUSIONS: Current vitamin D status was associated with tPA concentrations, and to a lesser degree with fibrinogen and D-dimer, suggesting that vitamin D status/intake may be important for maintaining antithrombotic homeostasis.

[Expression profiles and bioinformatic analysis of miRNA in human dental pulp cells during endothelial differentiation].

Science.gov (United States)

Gong, Qimei; Jiang, Hongwei; Wang, Jinming; Ling, Junqi

2014-05-01

To investigate the differential expression profile and bioinformatic analysis of microRNA (miRNA) in human dental pulp cells (DPC) during endothelial differentiation. DPC were cultured in endothelial induction medium (50 µg/L vascular endothelial growth factor, 10 µg/L basic fibroblast growth factor and 2% fetal calf serum) for 7 days. Meanwhile non-induced DPC were used as control.Quantitative real-time PCR (qRT-PCR) was applied to detect vascular endothelial marker genes [CD31, von Willebrand factor (vWF) and vascular endothelial-cadherin (VE-cadherin)] and in vitro tube formation on matrigel was used to analyze the angiogenic ability of differentiated cells. And then miRNA expression profiles of DPC were examined using miRNA microarray and then the differentially expressed miRNA were validated by qRT-PCR. Furthermore, bioinformatic analysis was employed to predict the target genes of miRNA and to analyze the possible biological functions and signaling pathways that were involved in DPC after induction. The relative mRNA level of CD31, vWF and VE-cadherin in the control group were (3.48 ± 0.22) ×10(-4), (3.13 ± 0.31) ×10(-4) and (39.60 ± 2.36) ×10(-4), and (19.57 ± 2.20) ×10(-4), (48.13 ± 0.54) ×10(-4) and (228.00 ± 8.89) ×10(-4) in the induced group. The expressions of CD31, vWF and VE-cadherin were increased significantly in endothelial induced DPC compared to the control group (P functions, such as the regulation of transcription, cell motion, blood vessel morphogenesis, angiogenesis and cytoskeletal protein, and signaling pathways including the mitogen-activated protein kinase (MAPK) and the Wnt signaling pathway. The differential miRNA expression identified in this study may be involved in governing DPC endothelial differentiation, thus contributing to the future research on regulatory mechanisms in dental pulp angiogenesis.

Bleeding score in Type 1 von Willebrand disease patients using the ISTH-BAT questionnaire.

Science.gov (United States)

Pathare, A; Al Omrani, S; Al Hajri, F; Al Obaidani, N; Al Balushi, B; Al Falahi, K

2018-04-01

Bleeding assessment tools have evolved in the last decade to standardize the assessment of the severity of bleeding symptom in a consistent way. In 2010, the International Society on Thrombosis and Hemostasis-Bleeding Assessment Tool (ISTH-BAT) was developed and validated. Our aim was to administer ISTH-BAT questionnaire to the Omani patients with type 1 VWD and obtain the bleeding score (BS). We also studied the severity of their bleeding symptoms and correlated it with the BS as well as with the laboratory parameters. Forty-eight type I VWD index cases and 52 normal subjects were interviewed and the ISTH-BAT questionnaire administered. The BS was calculated based on a history of bleeding symptoms from 12 different sites according to the standard ISTH-BAT questionnaire. Laboratory parameters were obtained from patient's medical records. The mean age of this cohort was 27 years (range, 6-49) with 60% being females. The median time to administer this questionnaire was 10 minutes with an interquartile range (IQR) from 8 to 17 minutes. Overall, the median BS was 7 (IQR; 2,11) although individual scores ranged between 0 and 36. The BS was negatively correlated with VWF: Ag, VWF: RCo, and VWF: CB and the Spearman's correlation coefficient "rho" was, respectively, -0.15, -0.08, and -0.22. The ISTH-BAT BS is designed to reflect the severity of bleeding. Our results demonstrate the inherent variability of this bleeding pattern. We also found that the ISTH-BAT BS significantly correlated with VWF: Ag and VWF: CB. © 2017 John Wiley & Sons Ltd.

The relationship of vascular endothelial marker and endothelium-dependent vasodilatation in patients with essential hypertension

International Nuclear Information System (INIS)

Chen Yongjian; Zhou Yonglie; Hu Qingfeng; Qiu Liannv

2009-01-01

Objective: To explore the relationship of vascular endothelial marker and endothelium-dependent vasodilatation in patients with essential hypertension (EH). Methods: Plasma endothlium (ET-1) (with RIA) and von Willber factor (vWF)(with ELISA) levels were measured both before and after 12 wks' treatment in 56 patients with essential hypertension and 32 controls. The brachial artery endothelium-dependent vasodilatation function was examined with high resolving color doppler ultra-sonography. The 56 patients with EH were of two groups A. high and very high risk, n=26 B. low and moderate risk, n=30. Results: Plasma levels of ET-1, vWF in patients with EH as a whole were significantly higher than those in controls group [(53.3±16.2)pg/ml vs(42.5±8.5)pg/ml, (158.2±28.6)% vs(130.6±35.2)%], endothelium-dependent vasodilatation function wasmuch reduced in patients with EH(7.5±4.2)% vs controls(12.3±4.3)%. Among the patients, values in Group A were significantly different from those in Group B. After treatment for 12 weeks, plasma ET-1 and vWF and endothelium-dependent vasodilatation function were significantly improved. There was negative correlation between vascular endothelial marker levels and endothelium-dependent vasodilatation function. Conclusion: The endothelium-dependent vasodilatation function was impaired and plasma ET-1 and vWF levels were increased in patients with EH, the endothelial dysfunction was closely associated with the risk level of EH. Vascular endothelial markers were useful indicators for evaluation of the endothelium-dependent vasodilatation function. (authors)

Effects of Partially Ionised Medical Oxygen, Especially with O2•−, in Vibration White Finger Patients

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Slavomír Perečinský

2014-05-01

Full Text Available A major symptom of hand-arm vibration syndrome is a secondary Raynaud’s phenomenon—vibration white finger (VWF—which results from a vasospasm of the digital arteries caused by work with vibration devices leading to occupational disease. Pharmacotherapy of VWF is often ineffective or has adverse effects. The aim of this work was to verify the influence of inhalation of partially ionized oxygen (O2•− on peripheral blood vessels in the hands of patients with VWF. Ninety one (91patients with VWF underwent four-finger adsorption plethysmography, and the pulse wave amplitude was recorded expressed in numeric parameters—called the native record. Next, a cold water test was conducted following with second plethysmography. The patients were divided in to the three groups. First and second inhaled 20-min of ionized oxygen O2•− or oxygen O2 respectively. Thirth group was control without treatment. All three groups a follow-up third plethysmography—the post-therapy record. Changes in the pulse wave amplitudes were evaluated. Inpatients group inhaling O2•− a modest increase of pulse wave amplitude was observed compared to the native record; patients inhaling medical oxygen O2 and the control showed a undesirable decline of pulse wave amplitude in VWF fingers. Strong vasodilatation were more frequent in the group inhaling O2•− compare to O2 (p < 0.05. Peripheral vasodilatation achieved by inhalation of O2•− could be used for VWF treatment without undesirable side effect in hospital as well as at home environment.

Characterization of the third component of complement (C3) after activation by cigarette smoke

International Nuclear Information System (INIS)

Kew, R.R.; Ghebrehiwet, B.; Janoff, A.

1987-01-01

Activation of lung complement by tobacco smoke may be an important pathogenetic factor in the development of pulmonary emphysema in smokers. We previously showed that cigarette smoke can modify C3 and activate the alternative pathway of complement in vitro. However, the mechanism of C3 activation was not fully delineated in these earlier studies. In the present report, we show that smoke-treated C3 induces cleavage of the alternative pathway protein, Factor B, when added to serum containing Mg-EGTA. This effect of cigarette smoke is specific for C3 since smoke-treated C4, when added to Mg-EGTA-treated serum, fails to activate the alternative pathway and fails to induce Factor B cleavage. Smoke-modified C3 no longer binds significant amounts of [ 14 C]methylamine (as does native C3), and relatively little [ 14 C]methylamine is incorporated into its alpha-chain. Thus, prior internal thiolester bond cleavage appears to have occurred in C3 activated by cigarette smoke. Cigarette smoke components also induce formation of noncovalently associated, soluble C3 multimers, with a Mr ranging from 1 to 10 million. However, prior cleavage of the thiolester bond in C3 with methylamine prevents the subsequent formation of these smoke-induced aggregates. These data indicate that cigarette smoke activates the alternative pathway of complement by specifically modifying C3 and that these modifications include cleavage of the thiolester bond in C3 and formation of noncovalently linked C3 multimers

Evolutionary history of the most speciose mammals: molecular phylogeny of muroid rodents.

OpenAIRE

Michaux, Johan; Reyes, A.; Catzeflis, F.

2001-01-01

Phylogenetic relationships between 32 species of rodents representing 14 subfamilies of Muridae and four subfamilies of Dipodidae were studied using sequences of the nuclear protein-coding genes Lecithin Cholesterol Acyl Transferase (LCAT) and von Willebrand Factor (vWF). An examination of some evolutionary properties of each data matrix indicates that the two genes are rather complementary, with lower rates of nonsynonymous substitutions for LCAT. Both markers exhibit a wide range of GC3 per...

Presentation of the Multimédia Game "Geolover" Concept, to Educational Enchancement of the Geolocical Heritage of the Following Regions: "Ilha do Fogo" (Cabo-Verde), Seridó (Brasil), Sabugal (Portugal) and Açores (Portugal)

Science.gov (United States)

Cabral, João; Gomes, Ana; Alfama, Vera; Oliveira, Sirlene; Pinharandas, Carlos; Fonseca, Pedro; Campos, José; Nobre, José

2013-04-01

"Geolover" - Presentation of the multimédia game concept, to educational enchancement of the geolocical heritage of the following regions: : "Ilha do Fogo" (Cabo-Verde), Seridó (Brasil), Sabugal and Açores (Portugal). "Geolover" is a multitouch game, played by four players simultaneously, identified by 4 mascots and using as sceneries, the four regions landscapes, aimed to the young people with ages between 8 and 12 years old. The main objective is value the geological heritage of the Ilha do Fogo (Cabo Verde), Seridó in State of Rio Grande do Norte (Brasil) , Sabugal in Beira Alta province (Portugal) and Arquipélago dos Açores (Portuguese autonomous region). These regions have a great geological heritage like volcanology, plutonic rocks, sedimentar formations, metamorphic, paleontologic, mineralogic, geomorphologic, hydric and mining resources. Such heritage is being used in the different regions has base of studies to senior scientists and were used to great scientific researches. The diversified and distinguished cultural heritage of these four regions is referenced and it's a value to the union of the students from these three continents, with the Portuguese language as communication tool. The variety of the geological wealth and cultural of these regions, results in the common objective of their valuing like Geoparks. His creation on these three regions is a strategy with a great relevance to the socio-economic development. With the creation of this game, we promote the union of these 3 countries from these three continents, the universal values of the heritage richness that are offered by our planet.

FUNCTIONAL STATE OF THE MICROCIRCULATION OF THE SKIN ACCORDING TO LASER DOPPLER FLOWMETRY IN PATIENTS WITH ATRIAL FIBRILLATION WHO UNDERWENT CARDIOEMBOLIC STROKE

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I. A. Zolotovskaya

2017-01-01

Full Text Available Aim. To evaluate the features of blood flow at the level of the microcirculatory bed of the skin (MC in the conditions of comorbid pathology and increased coagulation potential of the blood in patients with atrial fibrillation (AF.Material and methods. The following groups were formed by random sampling: the main (group 1, n=50 group of patients with paroxysmal or persistent form of AF, after cardioembolic stroke. The comparison group (group 2, n=50 consisted of patients with paroxysmal or persistent AF without a history of stroke. The control group (group 3, n=50 – patients comparable on the basic parameters of patients from groups 1 and 2, but without AF and stroke. The plasma levels of von Willebrand factor (vWF, tissue plasminogen activator inhibitor-1 (PAI-1, antithrombin III (AT III and plasminogen were determined. All MC parameters were studied with a single-channel laser cutaneous blood flow analyzer for the general practitioner "LAKK-OP" in the area of the finger pad during the period, when a patient had sinus rhythm.Results. The obtained results indicate the disorders of microcirculation processes in patients with AF after stroke, which are expressed in decrease in tissue perfusion, specific oxygen consumption (I and relative perfusion of the microcirculation saturation (Sm. Significantly higher levels of vWF, PAI-1 and low levels of AT III were observed in patients with AF and stroke than these in the group of patients with AF. It was found that Sm in patients of the group 1 statistically significantly correlated with vWF (r=-0.61; p=0.0032, plasminogen (r=0.45; p=0.0084, PAI-1 (r=-0.43; p=0.0027 and AT III (r=0.49; p=0.0065.Conclusion. The revealed disorders of microcirculatory processes are significantly related with the disturbances of the hemostatic function of the endothelium. From the pathophysiological point of view, that is one of the negative risk factors of the development of recurrent thrombus formation.

Protein mobilities and P-selectin storage in Weibel-Palade bodies.

Science.gov (United States)

Kiskin, Nikolai I; Hellen, Nicola; Babich, Victor; Hewlett, Lindsay; Knipe, Laura; Hannah, Matthew J; Carter, Tom

2010-09-01

Using fluorescence recovery after photobleaching (FRAP) we measured the mobilities of EGFP-tagged soluble secretory proteins in the endoplasmic reticulum (ER) and in individual Weibel-Palade bodies (WPBs) at early (immature) and late (mature) stages in their biogenesis. Membrane proteins (P-selectin, CD63, Rab27a) were also studied in individual WPBs. In the ER, soluble secretory proteins were mobile; however, following insertion into immature WPBs larger molecules (VWF, Proregion, tPA) and P-selectin became immobilised, whereas small proteins (ssEGFP, eotaxin-3) became less mobile. WPB maturation led to further decreases in mobility of small proteins and CD63. Acute alkalinisation of mature WPBs selectively increased the mobilities of small soluble proteins without affecting larger molecules and the membrane proteins. Disruption of the Proregion-VWF paracrystalline core by prolonged incubation with NH(4)Cl rendered P-selectin mobile while VWF remained immobile. FRAP of P-selectin mutants revealed that immobilisation most probably involves steric entrapment of the P-selectin extracellular domain by the Proregion-VWF paracrystal. Significantly, immobilisation contributed to the enrichment of P-selectin in WPBs; a mutation of P-selectin preventing immobilisation led to a failure of enrichment. Together these data shed new light on the transitions that occur for soluble and membrane proteins following their entry and storage into post-Golgi-regulated secretory organelles.

Plasma concentration of selected biochemical markers of endothelial dysfunction in women with various severity of chronic venous insufficiency (CVI-A pilot study.

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Magdalena Budzyń

Full Text Available Although the endothelial dysfunction is considered to be implicated in the pathogenesis of chronic venous insufficiency (CVI the endothelial status in patients with venous disorders is still not fully evaluated. Therefore the aim of the study was to measure the concentration of selected markers of endothelial dysfunction: von Willebrand factor (vWf, soluble P-selectin (sP-selectin, soluble thrombomodulin (sTM and soluble VE-cadherin (sVE-cadherin in CVI women who constitute the most numerous group of patients suffering from venous disease.Forty four women with CVI were involved in the study and divided into subgroups based on CEAP classification. Concentration of vWf, sP-selectin, sTM and sVE-cadherin were measured and compared with those obtained in 25 healthy age and sex-matched women.It was found that the concentration of sTM increased and sVEcadherin decreased along with disease severity in CVI women. A significant rise of sTM was observed especially in CVI women, with the highest inflammation status reflected by hsCRP or elastase concentration, and in CVI women with a high oxidative stress manifested by an increased plasma MDA. A significant fall of circulating sVE-cadherin was reported in CVI women with moderate to highest intensity of inflammation and oxidative stress. There was no change in vWF and sP-selectin concentration at any stage of CVI severity.The results of the present study demonstrate the presence of endothelial dysfunction in women suffering from CVI which seems to progress with the disease severity and may be associated with inflammation and enhanced oxidative stress.

Epidemiologic features of von Willebrand's disease in Doberman pinschers, Scottish terriers, and Shetland sheepdogs: 260 cases (1984-1988)

Science.gov (United States)

Brooks, M; Dodds, W J; Raymond, S L

1992-04-15

During a study period from 1985 through 1988, plasma von Willebrand's factor antigen (vWF:Ag) concentration was measured as a marker for prevalence of the von Willebrand's disease (vWD) trait in Doberman Pinschers (doberman, n = 5,554), Scottish Terriers (scottie, n = 1,363), and Shetland Sheepdogs (sheltie, n = 4,279). Significant increase in prevalence of the trait was seen in scotties and shelties during this period. In 1988, 73% of dobermans, 30% of scotties, and 28% of shelties tested had abnormal vWF:Ag concentration (less than 50% vWF:Ag). We found significant differences between breeds with respect to age and vWF:Ag concentration of clinically affected dogs at time of diagnosis. The affected dobermans were older (doberman mean age, 4.6 years; scottie mean age, 1.7 years; sheltie mean age, 1.9 years) and had higher concentration of plasma vWF:Ag (doberman mean vWF:Ag, 15%; scottie mean vWF:Ag, 0%; sheltie mean vWF:Ag, 8%). Bleeding in affected dogs of all 3 breeds was observed predominantly from mucosal surfaces and from cutaneous sites of surgery or trauma. The most common site of mucosal bleeding in scotties and shelties was oral or nasal cavity, and in dobermans was the urogenital tract. Differences in clinical manifestations of vWD in purebred dogs may reflect heterogeneous defects within the vWF gene, causing a variety of abnormalities in production, structure, and function of vWF protein. Analogous to vWD in human beings, acquired deficiencies of vWF may also contribute to the clinical variability of vWD in dogs.

In silico particle margination in blood flow

OpenAIRE

Müller, Kathrin

2015-01-01

A profound knowledge of margination, the migration of blood components to the vessel wall in blood flow, is required in order to understand the genesis of various diseases, as e.g., cardiovascular diseases or bleeding disorders. Margination of particles is a pre-condition for potential adhesion. Adhesion to the vessel wall is required for platelets, the protein von Willebrand factor (VWF), but also for drug and imaging agent carriers in order to perform their particular tasks. In the haemosta...

Sélection de parutions

Directory of Open Access Journals (Sweden)

2006-12-01

Full Text Available Si vous souhaitez soumettre une analyse d'ouvrage concernant le domaine des TIC et des langues, contactez-moi : foucher@lrl.univ-bpclermont.fr Paola NobiliOltre il libro di testo. Multimedialità e nuovi contesti per apprendere le lingueRoma : Carocci Faber, 2006ISBN : 88-7766-287-416,50 € Nicolas GuichonLangues et TICE - Méthodologie de conception multimédiaParis : Ophrys, collection Autoformation et Enseignement Multimédia, 2006ISBN : 2-7080-1155-3236 pages22 € Benoît HabertInstruments et re...

Analysis of the initiating events in HIV-1 particle assembly and genome packaging.

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Sebla B Kutluay

2010-11-01

Full Text Available HIV-1 Gag drives a number of events during the genesis of virions and is the only viral protein required for the assembly of virus-like particles in vitro and in cells. Although a reasonable understanding of the processes that accompany the later stages of HIV-1 assembly has accrued, events that occur at the initiation of assembly are less well defined. In this regard, important uncertainties include where in the cell Gag first multimerizes and interacts with the viral RNA, and whether Gag-RNA interaction requires or induces Gag multimerization in a living cell. To address these questions, we developed assays in which protein crosslinking and RNA/protein co-immunoprecipitation were coupled with membrane flotation analyses in transfected or infected cells. We found that interaction between Gag and viral RNA occurred in the cytoplasm and was independent of the ability of Gag to localize to the plasma membrane. However, Gag:RNA binding was stabilized by the C-terminal domain (CTD of capsid (CA, which participates in Gag-Gag interactions. We also found that Gag was present as monomers and low-order multimers (e.g. dimers but did not form higher-order multimers in the cytoplasm. Rather, high-order multimers formed only at the plasma membrane and required the presence of a membrane-binding signal, but not a Gag domain (the CA-CTD that is essential for complete particle assembly. Finally, sequential RNA-immunoprecipitation assays indicated that at least a fraction of Gag molecules can form multimers on viral genomes in the cytoplasm. Taken together, our results suggest that HIV-1 particle assembly is initiated by the interaction between Gag and viral RNA in the cytoplasm and that this initial Gag-RNA encounter involves Gag monomers or low order multimers. These interactions per se do not induce or require high-order Gag multimerization in the cytoplasm. Instead, membrane interactions are necessary for higher order Gag multimerization and subsequent

The Estrogen Receptor-β Expression in De Quervain’s Disease

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Po-Chuan Shen

2015-11-01

Full Text Available Stenosing tenosynovitis of the first dorsal compartment of the wrist (a.k.a. de Quervain’s disease is common but how estrogen is involved is still unknown. We previously reported that inflammation was involved in the pathogenesis of this ailment. In the present study, we extended our investigation of estrogen receptor (ER-β expression to determine whether estrogen is involved in the pathogenesis of de Quervain’s. Intraoperative retinaculum samples were collected from 16 patients with the ailment. Specimens were histologically graded by collagen structure and immunohistochemically evaluated by quantifying the expression of ER-β, interleukin (IL-1β and IL-6 (inflammatory cytokines, cyclooxygenase (COX-2 (an inflammatory enzyme, and vascular endothelial growth factor (VEGF, and Von Willebrand’s factor (vWF. De Quervain’s occurs primarily in women. The female:male ratio in our study was 7:1. We found that ER-β expression in the retinaculum was positively correlated with disease grade and patient age. Additionally, disease severity was associated with inflammatory factors—IL-1β and IL-6, COX-2, and VEGF and vWF in tenosynovial tissue. The greater the levels of ER-β expression, tissue inflammation, and angiogenesis are, the more severe de Quervain’s disease is. ER-β might be a useful target for novel de Quervain’s disease therapy.

Abnormal megakaryocyte development and platelet function in Nbeal2(-/-) mice.

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Kahr, Walter H A; Lo, Richard W; Li, Ling; Pluthero, Fred G; Christensen, Hilary; Ni, Ran; Vaezzadeh, Nima; Hawkins, Cynthia E; Weyrich, Andrew S; Di Paola, Jorge; Landolt-Marticorena, Carolina; Gross, Peter L

2013-11-07

Gray platelet syndrome (GPS) is an inherited bleeding disorder associated with macrothrombocytopenia and α-granule-deficient platelets. GPS has been linked to loss of function mutations in NEABL2 (neurobeachin-like 2), and we describe here a murine GPS model, the Nbeal2(-/-) mouse. As in GPS, Nbeal2(-/-) mice exhibit splenomegaly, macrothrombocytopenia, and a deficiency of platelet α-granules and their cargo, including von Willebrand factor (VWF), thrombospondin-1, and platelet factor 4. The platelet α-granule membrane protein P-selectin is expressed at 48% of wild-type levels and externalized upon platelet activation. The presence of P-selectin and normal levels of VPS33B and VPS16B in Nbeal2(-/-) platelets suggests that NBEAL2 acts independently of VPS33B/VPS16B at a later stage of α-granule biogenesis. Impaired Nbeal2(-/-) platelet function was shown by flow cytometry, platelet aggregometry, bleeding assays, and intravital imaging of laser-induced arterial thrombus formation. Microscopic analysis detected marked abnormalities in Nbeal2(-/-) bone marrow megakaryocytes, which when cultured showed delayed maturation, decreased survival, decreased ploidy, and developmental abnormalities, including abnormal extracellular distribution of VWF. Our results confirm that α-granule secretion plays a significant role in platelet function, and they also indicate that abnormal α-granule formation in Nbeal2(-/-) mice has deleterious effects on megakaryocyte survival, development, and platelet production.

Numerical modelling of mine workings: annual update 1999/2000.

CSIR Research Space (South Africa)

De wet Strydom, JP

2000-08-01

Full Text Available .1.2 Hand-arm vibration syndrome Probably the most important pathology associated with HAV is the vascular disorder hand-arm vibration syndrome, also known as Raynaud's phenomenon or Vibration White Finger (VWF). VWF is a vascular disorder that was first... one or more white fingers, 87% had feelings of numbness, tingling or cramps in their hands, and 82% had musculo-skeletal complaints. Measured exposure levels varied from 4 to 60 m/s2 (not weighted), depending on the tool type used. Moon et al...

Data on the purification and crystallization of the loss-of-function von Willebrand disease variant (p.Gly1324Ser of the von Willebrand factor A1 domain

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James C. Cambell

2016-06-01

In this data article we describe the production, quality control and crystallization of the p.Gly1324Ser vWD variant of the A1 domain of VWF. p.Gly1324Ser A1 was expressed in Escherichia coli as insoluble inclusion bodies. After the preparation of the inclusion bodies, the protein was solubilized, refolded, purified by affinity chromatography and crystallized. The crystal structure of the p.Gly1324Ser mutant of the A1 domain is deposited at the Protein Data Bank PDB: 5BV8

Evaluation of Energy Balance on Human Telomerase Reverse Transcriptase (hTERT) Alternative Splicing by Semi-quantitative RT-PCR in Human Umbilical Vein Endothelial Cells.

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Behjati, Mohaddeseh; Hashemi, Mohammad; Kazemi, Mohammad; Salehi, Mansoor; Javanmard, Shaghayegh Haghjooy

2017-01-01

Decreased high-energy phosphate level is involved in endothelial cell injury and dysfunction. Reduced telomerase activity in endothelial cells in parallel with reduced energy levels might be due to altered direction of alternative splicing machine as a complication of depleted energy during the process of atherosclerosis. Isolated human umbilical vein endothelial cells (HUVECs) were treated for 24 hours by oligomycine (OM) and 2-deoxy glucose (2-DG). After 24 hours, the effect of energy depletion on telomerase splicing pattern was evaluated using RT-PCR. Indeed, in both treated and untargeted cells, nitric oxide (NO) and von Willebrand factor (vWF) were measured. ATP was depleted in treated cells by 43.9% compared with control group. We observed a slight decrease in NO levels ( P = 0.09) and vWF ( P = 0.395) in the setting of 49.36% ATP depletion. In both groups, no telomerase gene expression was seen. Telomerase and housekeeping gene expression were found in positive control group (colon cancer tissue) and sample tissue. The absence of telomerase gene expression in HUVECs might be due to the mortality of these cells or the low level of telomerase gene expression in these cells under normal circumstances.

Percutaneous coronary intervention and the management of acute coronary syndromes in patients with von Willebrand disease.

Science.gov (United States)

Rathore, Sulaiman; Deleon, Dexter; Akram, Hafsa; Sane, David; Ball, Timothy

2013-04-01

Von Willebrand disease (vWD) results from quantitative or qualitative deficiency of von Willebrand factor (vWF). The occurrence of myocardial infarction is very rare in patients with vWD. A few case reports of acute coronary syndrome (ACS) in vWD patients are present in the literature, but no definite management recommendations are available for such patients. We report a case of successful percutaneous coronary intervention (PCI) with bare-metal stent (BMS) implantation in a 46-year-old woman with type 1 vWD and history of coronary artery disease (CAD). She received periprocedural dual-antiplatelet therapy for 2 weeks and then continued aspirin without any bleeding complications. The optimal management of patients with vWD and ACS is complex and presents a therapeutic challenge. We propose that dual-antiplatelet therapy can be used safely in most vWD patients presenting with ACS as most of them are type 1 vWD. PCI with BMS can be done safely. Long-term management of these patients requires a systemic approach including hematological consultation, ascertaining vWF levels, as well as patient education and close outpatient follow-up.

Disseny i optimització metològica de sistemes telemàtics interactius per a la millora de la docència universitària : l'entorn BSCW i nous recursos docents

OpenAIRE

Llitjós Viza, Anna

2011-01-01

Aquest projecte de dos anys de durada, ha tingut com a objectius: el disseny i la creació de recursos multimèdia, així com, l’optimització de metodologies d'aplicació de sistemes telemàtics interactius per a la millora de la docència universitària. Com a entorn telemàtic s’ha utilitzat la plataforma de treball cooperatiu BSCW (Basic Support for Cooperative Work). S'ha dissenyat i produït un recurs multimèdia enfocat a l'alumnat de l'assignatura troncal Ciències naturals i la se...

PO-58 - Cardiovascular risk profile in survivors of adult cancer - results from the general population study.

Science.gov (United States)

Panova-Noeva, M; Hermanns, I M; Schulz, A; Laubert-Reh, D; Zeller, T; Blankenberg, S; Spronk, H M; Münzel, T; Lackner, K J; Ten Cate, H; Wild, P S

2016-04-01

The advancements in cancer treatment and detection of early cancer have resulted in steady increase of adult cancer survivors over the years. However, due to the long term toxic effects of chemotherapy and radiotherapy, the incidence of cardiovascular diseases (CVD) is increasing in survivors. Identifying risk factors and interventions to reduce the excess burden of CVD in this vulnerable population is urgently needed. To investigate the cardiovascular risk factors (CVRFs), inflammation and coagulation profile in cancer survivors from a large population-based study. Presence of CVRFs and laboratory markers have been compared in individuals with (n=1,359) and without (n=13,626) history of cancer. Standard laboratory profile, including blood glucose and lipid profile, has been evaluated in 15,010 individuals from the Gutenberg Health Study (GHS). Coagulation factors, D-dimer and von Willebrand factor (vWF) activity were available in N=4,993. The individuals with history of cancer were older compared to no history of cancer with mean age of 61,5years and 54.4years, respectively (pprofile showed cancer survivors with lower erythrocyte, platelet and white blood cell counts and higher C-reactive protein (CRP), glucose, HbA1c and triglycerides levels (pprofile in individuals with history of cancer from a well characterized population-representative adult sample. It gives evidence for higher prevalence of CVRFs, particularly diabetes in this vulnerable population. Markers of inflammation as CRP and fibrinogen and vWF activity were higher in cancer survivors independent of the cardiovascular risk profile. These results underline the increased risk of CVD and need for development of cardio-oncology programs offering cardiovascular prevention. © 2016 Elsevier Ltd. All rights reserved.

Bleeding from gastrointestinal angioectasias is not related to bleeding disorders - a case control study

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Lärfars Gerd

2010-09-01

Full Text Available Abstract Background Angioectasias in the gastrointestinal tract can be found in up to 3% of the population. They are typically asymptomatic but may sometimes result in severe bleeding. The reasons for why some patients bleed from their angioectasias are not fully understood but it has been reported that it may be explained by an acquired von Willebrand syndrome (AVWS. This condition has similar laboratory findings to congenital von Willebrand disease with selective loss of large von Willebrand multimers. The aim of this study was to find out if AVWS or any other bleeding disorder was more common in patients with bleeding from angioectasias than in a control group. Methods We compared bleeding tests and coagulation parameters, including von Willebrand multimers, from a group of 23 patients with anemia caused by bleeding from angioectasias, with the results from a control group lacking angioectasias. Results No significant differences between the two groups were found in coagulation parameters, bleeding time or von Willebrand multimer levels. Conclusion These results do not support a need for routine bleeding tests in cases of bleeding from angioectasias and do not show an overall increased risk of AVWS among these patients.

Purification and characterization of a heteromultimeric glycoprotein from Artocarpus heterophyllus latex with an inhibitory effect on human blood coagulation.

Science.gov (United States)

Siritapetawee, Jaruwan; Thammasirirak, Sompong

2011-01-01

Plant latex has many health benefits and has been used in folk medicine. In this study, the biological effect of Artocarpus heterophyllus (jackfruit) latex on human blood coagulation was investigated. By a combination of heat precipitation and ion-exchange chromatography, a heat stable heteromultimeric glycoprotein (HSGPL1) was purified from jackfruit milky latex. The apparent molecular masses of the monomeric proteins on SDS/PAGE were 33, 31 and 29 kDa. The isoelectric points (pIs) of the monomers were 6.63, 6.63 and 6.93, respectively. Glycosylation and deglycosylation tests confirmed that each subunit of HSGPL1 formed the native multimer by sugar-based interaction. Moreover, the multimer of HSGPL1 also resisted 2-mercaptoethanol action. Peptide mass fingerprint analysis indicated that HSGPL1 was a complex protein related to Hsps/chaperones. HSGPL1 has an effect on intrinsic pathways of the human blood coagulation system by significantly prolonging the activated partial thrombin time (APTT). In contrast, it has no effect on the human extrinsic blood coagulation system using the prothrombin time (PT) test. The prolonged APTT resulted from the serine protease inhibitor property of HSGPL1, since it reduced activity of human blood coagulation factors XI(a) and α-XII(a).

Abnormal megakaryocyte development and platelet function in Nbeal2−/− mice

Science.gov (United States)

Lo, Richard W.; Li, Ling; Pluthero, Fred G.; Christensen, Hilary; Ni, Ran; Vaezzadeh, Nima; Hawkins, Cynthia E.; Weyrich, Andrew S.; Di Paola, Jorge; Landolt-Marticorena, Carolina; Gross, Peter L.

2013-01-01

Gray platelet syndrome (GPS) is an inherited bleeding disorder associated with macrothrombocytopenia and α-granule-deficient platelets. GPS has been linked to loss of function mutations in NEABL2 (neurobeachin-like 2), and we describe here a murine GPS model, the Nbeal2−/− mouse. As in GPS, Nbeal2−/− mice exhibit splenomegaly, macrothrombocytopenia, and a deficiency of platelet α-granules and their cargo, including von Willebrand factor (VWF), thrombospondin-1, and platelet factor 4. The platelet α-granule membrane protein P-selectin is expressed at 48% of wild-type levels and externalized upon platelet activation. The presence of P-selectin and normal levels of VPS33B and VPS16B in Nbeal2−/− platelets suggests that NBEAL2 acts independently of VPS33B/VPS16B at a later stage of α-granule biogenesis. Impaired Nbeal2−/− platelet function was shown by flow cytometry, platelet aggregometry, bleeding assays, and intravital imaging of laser-induced arterial thrombus formation. Microscopic analysis detected marked abnormalities in Nbeal2−/− bone marrow megakaryocytes, which when cultured showed delayed maturation, decreased survival, decreased ploidy, and developmental abnormalities, including abnormal extracellular distribution of VWF. Our results confirm that α-granule secretion plays a significant role in platelet function, and they also indicate that abnormal α-granule formation in Nbeal2−/− mice has deleterious effects on megakaryocyte survival, development, and platelet production. PMID:23861251

Data for a direct fibrinolytic metalloproteinase, barnettlysin-I from Bothrops barnetti (barnett,s pitviper) snake venom with anti-thrombotic effect

Science.gov (United States)

Sanchez, Eladio Flores; Richardson, Michael; Gremski, Luiza Helena; Veiga, Silvio Sanches; Yarleque, Armando; Niland, Stephan; Lima, Augusto Martins; Estevao-Costa, Maria Inácia; Eble, Johannes Andreas

2016-01-01

Initial association of platelets after vascular injury is mediated by glycoprotein (GP)Ib-IX-V binding to von Willebrand factor (vWf) immobilized on exposed collagens and eventually leads to thrombus formation. This article provides data about a new P-I class snake venom metalloproteinase (SVMP), barnettlysin-I (Bar-I), purified from the venom of Bothrops barnetti. This Data in Brief manuscript complements the main research article by providing additional data of the biochemical characterization of Bar-I 10.1016/j.bbagen.2015.12.021[1]. PMID:27222863

Factors promoting development of renal tubulointerstitial lesions in patients with diabetes mellitus

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Minara Shamkhalovna Shamkhalova

2010-09-01

Full Text Available Aim. To identify profibrogenic mediators, markers of endothelial dysfunction and hemostasis in patients with diabetes mellitus (DM and chronickidney disease (CKD. Materials and methods. The study included 120 patients with DM and 20 age-matched normotensive subjects without DM showing the glomerularfiltration rate (GFR > 60 ml/min/1.73 m3. Four groups of patients were distinguished: 1 - DM2 patients without renal pathology (n=33, 2 - DM2 patients with diabetic nephropathy (n=24, 3 - DM2 patients with ischemic nephropathy (IN (n=33 verified by contrast visualization techniques(multispiral CM of abdominal aorta and renal arteries, abdominal angiography of renal arteries or MR angiography of renal arteries and abdominal aorta, 4 - DM1 patients with DN (n=30. Clinical examination included assessment of complaints, analysis of medical history of the main diseaseand concomitant disorders, determination of the main clinical and biochemical characteristics of blood and urine, measurement of НbА1с and 24-hralbuminuria (AU by standard methods, estimation of GFR by the MDRD formula, ECG, echocardiography, 24-hr AP monitoring, counseling bycardiologist and ophthalmologist (fundal examination by ophthalmoscopy. Standard kits were used to detect profibrogenic mediators and markersof endothelial dysfunction including transforming growth factor-beta (TGF-b, angiotensin II (AT II, monocyte chemoattractant protein (MCP-1,regulated on activation normal T cell expressed and secreted (RANTES, adhesion factors (intracellular adhesion molecule (ICAM-1, vascular celladhesion molecule (VCAM-1 vascular endothelial growth factor (VEGF, interleukin-6 (IL-6, asymmetric dimethylargnine (ADMA, homocysteine(HCYST, metalloproteinases (MMP, von Willebrand factor (vWF, plasminogen activator inhibitor (PAI-I. Results. DM patients with CKD had elevated blood profibrogenic cytokine (MCP-1, TGF-1b, IL-6 and extracellular matrix degradation factor(MMP-9 levels compared with

Extension of Tissue Plasminogen Activator Treatment Window by Granulocyte-Colony Stimulating Factor in a Thromboembolic Rat Model of Stroke

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Ike C. dela Peña

2018-05-01

Full Text Available When given beyond 4.5 h of stroke onset, tissue plasminogen activator (tPA induces deleterious side effects in the ischemic brain, notably, hemorrhagic transformation (HT. We examined the efficacy of granulocyte-colony stimulating factor (G-CSF in reducing delayed tPA-induced HT, cerebral infarction, and neurological deficits in a thromboembolic (TE stroke model, and whether the effects of G-CSF were sustained for longer periods of recovery. After stroke induction, rats were given intravenous saline (control, tPA (10 mg/kg, or G-CSF (300 μg/kg + tPA 6 h after stroke. We found that G-CSF reduced delayed tPA-associated HT by 47%, decreased infarct volumes by 33%, and improved motor and neurological deficits by 15% and 25%, respectively. It also prevented delayed tPA treatment-induced mortality by 46%. Immunohistochemistry showed 1.5- and 1.8-fold enrichment of the endothelial progenitor cell (EPC markers CD34+ and VEGFR2 in the ischemic cortex and striatum, respectively, and 1.7- and 2.8-fold increases in the expression of the vasculogenesis marker von Willebrand factor (vWF in the ischemic cortex and striatum, respectively, in G-CSF-treated rats compared with tPA-treated animals. Flow cytometry revealed increased mobilization of CD34+ cells in the peripheral blood of rats given G-CSF. These results corroborate the efficacy of G-CSF in enhancing the therapeutic time window of tPA for stroke treatment via EPC mobilization and enhancement of vasculogenesis.

Atorvastatin effect on values of endotheli-al condition and acute inflammation in patients on program hemodialysis

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Barsuk A.L

2013-03-01

Full Text Available Objective: To study the effect of atorvastatin on the values of endothelial condition and acute inflammation in patients on program hemodialysis (PHD. Material and methods: The patients were divided into two groups: 28 PHD patients (main group received atorvastatin, 20 mg once a day for 30 days, and 26 patients (control group had PHD only. Endothelin 1-21 (ET level and von Willebrand factor (vWF activity were determined by enzyme immunoassay, nitric oxide (NO levels — spectrophotometrically, C-reactive protein (CRP — by immunoturbidimetric method, fibrinogen — by Clauss method. Results: After 30 days of observation, control patients were found to have NO and ET increase, as well as the reduced activity of vWF relative to initial data, while fibrinogen and CRP levels scarcely changed. The main group patients had similar changes of endothelial condition values, and their fibrinogen and CRP levels decreased. The correlation between the changes of ET and fibrinogen levels was recorded in the patients of the main group. Conclusion: 30-day administration of atorvastatin, 20 mg per day, lowers CRP and fibrinogen levels in PHD patients. It proves the applicability of statins in this group of patients in case of signs of inflammation.

Establishment of canine hemangiosarcoma xenograft models expressing endothelial growth factors, their receptors, and angiogenesis-associated homeobox genes

International Nuclear Information System (INIS)

Kodama, Atsushi; Yanai, Tokuma; Sakai, Hiroki; Matsuura, Satoko; Murakami, Mami; Murai, Atsuko; Mori, Takashi; Maruo, Kouji; Kimura, Tohru; Masegi, Toshiaki

2009-01-01

Human hemangiosarcoma (HSA) tends to have a poor prognosis; its tumorigenesis has not been elucidated, as there is a dearth of HSA clinical specimens and no experimental model for HSA. However, the incidence of spontaneous HSA is relatively high in canines; therefore, canine HSA has been useful in the study of human HSA. Recently, the production of angiogenic growth factors and their receptors in human and canine HSA has been reported. Moreover, the growth-factor environment of HSA is very similar to that of pathophysiological angiogenesis, which some homeobox genes regulate in the transcription of angiogenic molecules. In the present study, we established 6 xenograft canine HSA tumors and detected the expression of growth factors, their receptors, and angiogenic homeobox genes. Six primary canine HSAs were xenografted to nude mice subcutaneously and serially transplanted. Subsequently, the expressions of vascular endothelial growth factor (VEGF)-A, basic fibroblast growth factors (bFGF), flt-1 and flk-1 (receptors of VEGF-A), FGFR-1, and angiogenic homeobox genes HoxA9, HoxB3, HoxB7, HoxD3, Pbx1, and Meis1 were investigated in original and xenograft tumors by histopathology, immunostaining, and reverse transcription polymerase chain reaction (RT-PCR), using canine-specific primer sets. Histopathologically, xenograft tumors comprised a proliferation of neoplastic cells that were varied in shape, from spindle-shaped and polygonal to ovoid; some vascular-like structures and vascular clefts of channels were observed, similar to those in the original tumors. The expression of endothelial markers (CD31 and vWF) was detected in xenograft tumors by immunohistochemistry and RT-PCR. Moreover, the expression of VEGF-A, bFGF, flt-1, flk-1, FGFR-1, HoxA9, HoxB3, HoxB7, HoxD3, Pbx1, and Meis1 was detected in xenograft tumors. Interestingly, expressions of bFGF tended to be higher in 3 of the xenograft HSA tumors than in the other tumors. We established 6 xenograft canine HSA

APOBEC3G enhances lymphoma cell radioresistance by promoting cytidine deaminase-dependent DNA repair.

Science.gov (United States)

Nowarski, Roni; Wilner, Ofer I; Cheshin, Ori; Shahar, Or D; Kenig, Edan; Baraz, Leah; Britan-Rosich, Elena; Nagler, Arnon; Harris, Reuben S; Goldberg, Michal; Willner, Itamar; Kotler, Moshe

2012-07-12

APOBEC3 proteins catalyze deamination of cytidines in single-stranded DNA (ssDNA), providing innate protection against retroviral replication by inducing deleterious dC > dU hypermutation of replication intermediates. APOBEC3G expression is induced in mitogen-activated lymphocytes; however, no physiologic role related to lymphoid cell proliferation has yet to be determined. Moreover, whether APOBEC3G cytidine deaminase activity transcends to processing cellular genomic DNA is unknown. Here we show that lymphoma cells expressing high APOBEC3G levels display efficient repair of genomic DNA double-strand breaks (DSBs) induced by ionizing radiation and enhanced survival of irradiated cells. APOBEC3G transiently accumulated in the nucleus in response to ionizing radiation and was recruited to DSB repair foci. Consistent with a direct role in DSB repair, inhibition of APOBEC3G expression or deaminase activity resulted in deficient DSB repair, whereas reconstitution of APOBEC3G expression in leukemia cells enhanced DSB repair. APOBEC3G activity involved processing of DNA flanking a DSB in an integrated reporter cassette. Atomic force microscopy indicated that APOBEC3G multimers associate with ssDNA termini, triggering multimer disassembly to multiple catalytic units. These results identify APOBEC3G as a prosurvival factor in lymphoma cells, marking APOBEC3G as a potential target for sensitizing lymphoma to radiation therapy.

VE-Cadherin-Mediated Epigenetic Regulation of Endothelial Gene Expression.

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Morini, Marco F; Giampietro, Costanza; Corada, Monica; Pisati, Federica; Lavarone, Elisa; Cunha, Sara I; Conze, Lei L; O'Reilly, Nicola; Joshi, Dhira; Kjaer, Svend; George, Roger; Nye, Emma; Ma, Anqi; Jin, Jian; Mitter, Richard; Lupia, Michela; Cavallaro, Ugo; Pasini, Diego; Calado, Dinis P; Dejana, Elisabetta; Taddei, Andrea

2018-01-19

The mechanistic foundation of vascular maturation is still largely unknown. Several human pathologies are characterized by deregulated angiogenesis and unstable blood vessels. Solid tumors, for instance, get their nourishment from newly formed structurally abnormal vessels which present wide and irregular interendothelial junctions. Expression and clustering of the main endothelial-specific adherens junction protein, VEC (vascular endothelial cadherin), upregulate genes with key roles in endothelial differentiation and stability. We aim at understanding the molecular mechanisms through which VEC triggers the expression of a set of genes involved in endothelial differentiation and vascular stabilization. We compared a VEC-null cell line with the same line reconstituted with VEC wild-type cDNA. VEC expression and clustering upregulated endothelial-specific genes with key roles in vascular stabilization including claudin-5 , vascular endothelial-protein tyrosine phosphatase ( VE-PTP ), and von Willebrand factor ( vWf ). Mechanistically, VEC exerts this effect by inhibiting polycomb protein activity on the specific gene promoters. This is achieved by preventing nuclear translocation of FoxO1 (Forkhead box protein O1) and β-catenin, which contribute to PRC2 (polycomb repressive complex-2) binding to promoter regions of claudin-5 , VE-PTP , and vWf . VEC/β-catenin complex also sequesters a core subunit of PRC2 (Ezh2 [enhancer of zeste homolog 2]) at the cell membrane, preventing its nuclear translocation. Inhibition of Ezh2/VEC association increases Ezh2 recruitment to claudin-5 , VE-PTP , and vWf promoters, causing gene downregulation. RNA sequencing comparison of VEC-null and VEC-positive cells suggested a more general role of VEC in activating endothelial genes and triggering a vascular stability-related gene expression program. In pathological angiogenesis of human ovarian carcinomas, reduced VEC expression paralleled decreased levels of claudin-5 and VE-PTP. These

Evolutionary history of the most speciose mammals: molecular phylogeny of muroid rodents.

Science.gov (United States)

Michaux, J; Reyes, A; Catzeflis, F

2001-11-01

Phylogenetic relationships between 32 species of rodents representing 14 subfamilies of Muridae and four subfamilies of Dipodidae were studied using sequences of the nuclear protein-coding genes Lecithin Cholesterol Acyl Transferase (LCAT) and von Willebrand Factor (vWF). An examination of some evolutionary properties of each data matrix indicates that the two genes are rather complementary, with lower rates of nonsynonymous substitutions for LCAT. Both markers exhibit a wide range of GC3 percentages (55%-89%), with several taxa above 70% GC3 for vWF, which indicates that those exonic regions might belong to the richest class of isochores. The primary sequence data apparently harbor few saturations, except for transitions on third codon positions for vWF, as indicated by comparisons of observed and expected pairwise values of substitutions. Phylogenetic trees based on 1,962 nucleotidic sites from the two genes indicate that the 14 Muridae subfamilies are organized into five major lineages. An early isolation leads to the clade uniting the fossorial Spalacinae and semifossorial Rhizomyinae with a strong robustness. The second lineage includes a series of African taxa representing nesomyines, dendromurines, cricetomyines, and the sole living member of mystromyines. The third one comprises only the mouselike hamster CALOMYSCUS: The fourth clade represents the cricetines, myospalacines, sigmodontines, and arvicolines, whereas the fifth one comprises four "traditional" subfamilies (Gerbillinae, Murinae, Otomyinae, and Acomyinae). Within these groups, we confirm the monophyly of almost all studied subfamilies, namely, Spalacinae, Rhizomyinae, Nesomyinae, Cricetomyinae, Arvicolinae, Sigmodontinae, Cricetinae, Gerbillinae, Acomyinae, and Murinae. Finally, we present evidence that the sister group of Acomyinae is Gerbillinae, and we confirm a nested position of Myospalacinae within Cricetinae and Otomyinae within Murinae. From a biogeographical point of view, the five main

Snake-venom resistance as a mammalian trophic adaptation: lessons from didelphid marsupials.

Science.gov (United States)

Voss, Robert S; Jansa, Sharon A

2012-11-01

Mammals that prey on venomous snakes include several opossums (Didelphidae), at least two hedgehogs (Erinaceidae), several mongooses (Herpestidae), several mustelids, and some skunks (Mephitidae). As a group, these taxa do not share any distinctive morphological traits. Instead, mammalian adaptations for ophiophagy seem to consist only in the ability to resist the toxic effects of snake venom. Molecular mechanisms of venom resistance (as indicated by biochemical research on opossums, mongooses, and hedgehogs) include toxin-neutralizing serum factors and adaptive changes in venom-targeted molecules. Of these, toxin-neutralizing serum factors have received the most research attention to date. All of the toxin-neutralizing serum proteins discovered so far in both opossums and mongooses are human α1B-glycoprotein homologs that inhibit either snake-venom metalloproteinases or phospholipase A(2) myotoxins. By contrast, adaptive changes in venom-targeted molecules have received far less attention. The best-documented examples include amino-acid substitutions in mongoose nicotinic acetylcholine receptor that inhibit binding by α-neurotoxins, and amino-acid substitutions in opossum von Willebrand factor (vWF) that are hypothesized to weaken the bond between vWF and coagulopathic C-type lectins. Although multiple mechanisms of venom resistance are known from some species, the proteomic complexity of most snake venoms suggests that the evolved biochemical defences of ophiophagous mammals are likely to be far more numerous than currently recognized. Whereas most previous research in this field has been motivated by the potential for medical applications, venom resistance in ophiophagous mammals is a complex adaptation that merits attention from comparative biologists. Unfortunately, evolutionary inference is currently limited by ignorance about many relevant facts that can only be provided by future research. © 2012 The Authors. Biological Reviews © 2012 Cambridge

Pilot study of novel lab methodology and testing of platelet function in adolescent women with heavy menstrual bleeding.

Science.gov (United States)

Rocheleau, Anne D; Khader, Ayesha; Ngo, Anh T P; Boehnlein, Colin; McDavitt, Cara; Lattimore, Susan; Recht, Michael; McCarty, Owen J T; Haley, Kristina M

2018-03-01

BackgroundApproximately 40% of adolescent women experience heavy menstrual bleeding (HMB), and 10-62% of them have an underlying bleeding disorder (BD). Diagnosing a BD remains challenging because of limitations of available clinical platelet function assays. The aim of this study was to characterize platelet function in a population of adolescent women with HMB using small-volume whole-blood assays.MethodsAnticoagulated whole blood was used to assess platelet GPIIbIIIa activation, α-granule secretion, and aggregation in response to multiple agonists. Platelet adhesion on collagen or von Willebrand Factor (VWF) under static and shear flow was also assessed.ResultsFifteen participants with HMB were included in the study, of which eight were diagnosed with a clinically identifiable BD. Platelet activation was blunted in response to calcium ionophore in participants without a BD diagnosis compared with that in all other participants. Impaired GPIIbIIIa activation was observed in response to all GPCR agonists, except adenosine diphosphate (ADP), in participants with qualitative platelet disorders. Our assays detected platelet aggregation in the majority of participants with a BD in response to ADP, collagen-related peptide (CRP), thrombin receptor activator 6 (TRAP-6), or U46619. Platelet adhesion and aggregation on collagen and VWF was decreased for participants with VWD.ConclusionParticipants with and without BD exhibited aberrant platelet function in several assays in response to select agonists.

Factores de riesgo relacionados al uso de drogas ilegales: perspectiva crítica de familiares y personas cercanas en un centro de salud público en San Pedro Sula, Honduras Fatores de risco relacionados ao uso de drogas ilegais, perspectiva crítica de familiares e pessoas próximas, em um centro da saúde público em San Pedro Sula, Honduras Risk factors related to the use of illegal drugs: the critial perspective of drug users' relatives and acquaintances at a public health center in San Pedro Sula, Honduras

Directory of Open Access Journals (Sweden)

Gladys Magdalena Rodríguez Funes

2009-01-01

Full Text Available En este estudio, se presentan datos cuantitativos del estudio multicéntrico, multimétodos, de corte transversal realizado en un centro de salud público en San Pedro Sula, en Honduras. Su objetivo es describir la perspectiva crítica que tienen los familiares o personas, que se consideran afectadas por tener a alguien cercano que usa o ha usado drogas ilegales, con relación a factores de riesgo. Los datos se obtuvieron mediante una encuesta con 100 entrevistados. La mayor parte de las personas informantes eran mujeres pobres con baja escolaridad. Los consumidores eran en su mayoría hombres con edad promedio de 23,3 años. La droga más usada fue la marihuana (78% seguida de crack/cocaína (72%, pegamento/inhalantes (27%, alucinógenos (éxtasis/LSD (3%, anfetaminas/estimulantes (1% y heroína (1%. Los factores de riesgo identificados fueron la experiencia previa con alcohol/tabaco, el tener amigos/amigas que usan drogas, la falta de conocimiento, la baja autoestima , la edad, entre otros factores personales, familiares y sociales. Se concluye que es necesario fortalecer las medidas de prevención y protección.São apresentados, aqui, dados quantitativos de um estudo multicêntrico, multimétodos, de corte transversal, realizado em um centro de saúde pública em San Pedro Sula, Honduras. O objetivo foi descrever a perspectiva crítica dos membros da família ou pessoas que se sentem afetadas por terem alguém próximo que usa ou usou drogas ilegais, em relação aos fatores de risco. Os dados foram coletados através de questionário aplicado em 100 indivíduos. A maioria era composta por mulheres pobres, com pouca escolaridade. Os consumidores eram majoritariamente varões, com idade média de 23,3 anos. A droga mais utilizada foi a maconha (78%, seguida por crack/cocaína (72%, cola/inalantes (27%, alucinógenos (ecstasy/LSD (3%, anfetaminas/estimulantes (1%, heroína (1%. Entre os fatores de risco identificados estão: experi

Fibronectin alters the rate of formation and structure of the fibrin matrix.

Science.gov (United States)

Ramanathan, Anand; Karuri, Nancy

2014-01-10

Plasma fibronectin is a vital component of the fibrin clot; however its role on clot structure is not clearly understood. The goal of this study was to examine the influence of fibronectin on the kinetics of formation, structural characteristics and composition of reconstituted fibrin clots or fibrin matrices. Fibrin matrices were formed by adding thrombin to 1, 2 or 4 mg/ml fibrinogen supplemented with 0-0.4 mg/ml fibronectin. The rate of fibrin matrix formation was then monitored by measuring light absorbance properties at different time points. Confocal microscopy of fluorescein conjugated fibrinogen was used to visualize the structural characteristics of fibrin matrices. The amount of fibronectin in fibrin matrices was determined through electrophoresis and immunoblotting of solubilized matrices. Fibronectin concentration positively correlated with the initial rate of fibrin matrix formation and with steady state light absorbance values of fibrin matrices. An increase in fibronectin concentration resulted in thinner and denser fibers in the fibrin matrices. Electrophoresis and immunoblotting showed that fibronectin was covalently and non-covalently bound to fibrin matrices and in the form of high molecular weight multimers. The formation of fibronectin multimers was attributed to cross-linking of fibronectin by trace amounts Factor XIIIa. These findings are novel because they link results from light absorbance studies to microcopy analyses and demonstrate an influence of fibronectin on fibrin matrix structural characteristics. This data is important in developing therapies that destabilize fibrin clots. Copyright © 2014. Published by Elsevier Inc.

Laminin Peptide-Immobilized Hydrogels Modulate Valve Endothelial Cell Hemostatic Regulation.

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Liezl Rae Balaoing

Full Text Available Valve endothelial cells (VEC have unique phenotypic responses relative to other types of vascular endothelial cells and have highly sensitive hemostatic functions affected by changes in valve tissues. Furthermore, effects of environmental factors on VEC hemostatic function has not been characterized. This work used a poly(ethylene glycol diacrylate (PEGDA hydrogel platform to evaluate the effects of substrate stiffness and cell adhesive ligands on VEC phenotype and expression of hemostatic genes. Hydrogels of molecular weights (MWs 3.4, 8, and 20 kDa were polymerized into platforms of different rigidities and thiol-modified cell adhesive peptides were covalently bound to acrylate groups on the hydrogel surfaces. The peptide RKRLQVQLSIRT (RKR is a syndecan-1 binding ligand derived from laminin, a trimeric protein and a basement membrane matrix component. Conversely, RGDS is an integrin binding peptide found in many extracellular matrix (ECM proteins including fibronectin, fibrinogen, and von Willebrand factor (VWF. VECs adhered to and formed a stable monolayer on all RKR-coated hydrogel-MW combinations. RGDS-coated platforms supported VEC adhesion and growth on RGDS-3.4 kDa and RGDS-8 kDa hydrogels. VECs cultured on the softer RKR-8 kDa and RKR-20 kDa hydrogel platforms had significantly higher gene expression for all anti-thrombotic (ADAMTS-13, tissue factor pathway inhibitor, and tissue plasminogen activator and thrombotic (VWF, tissue factor, and P-selectin proteins than VECs cultured on RGDS-coated hydrogels and tissue culture polystyrene controls. Stimulated VECs promoted greater platelet adhesion than non-stimulated VECs on their respective culture condition; yet stimulated VECs on RGDS-3.4 kDa gels were not as responsive to stimulation relative to the RKR-gel groups. Thus, the syndecan binding, laminin-derived peptide promoted stable VEC adhesion on the softer hydrogels and maintained VEC phenotype and natural hemostatic function. In

Virtual histology assessment of cardiac allograft vasculopathy following introduction of everolimus--results of a multicenter trial

DEFF Research Database (Denmark)

Arora, Stina Jørgensen; Erikstad, I; Ueland, T

2012-01-01

of cardiac allograft vasculopathy (CAV). Parallel measurement of a range of inflammatory markers was also performed. A similar rate of quantitative CAV progression was observed in the everolimus (n = 30) and standard CNI group (n = 48) (plaque index 1.9 ± 3.8% and 1.6 ± 3.9%, respectively; p = 0.65). However...... with time since HTx >5.1 years and was accompanied by a significant increase in levels of von Willebrand (vWF) factor (p = 0.04) and vascular cell adhesion molecule (VCAM) (p = 0.03). Conversion to everolimus and reduced CNI is associated with a significant increase in calcified and necrotic intimal...

Revue d'Information Scientifique et Technique - Vol 5, No 1 (1995)

African Journals Online (AJOL)

COCACOM : environnement de développement d'applications coopérantes et multimédia · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. J-M. Inglebert, L Courtrai, S Sadou ...

Endothelial dysfunction and inflammation predict development of diabetic nephropathy in the Irbesartan in Patients with Type 2 Diabetes and Microalbuminuria (IRMA 2) study

DEFF Research Database (Denmark)

Persson, Frederik; Rossing, Peter; Hovind, Peter

2008-01-01

OBJECTIVE: To evaluate risk factors for progression from persistent microalbuminuria to diabetic nephropathy in the Irbesartan in Patients with Type 2 diabetes and Microalbuminuria (IRMA 2) study, including biomarkers of endothelial dysfunction, chronic low-grade inflammation, growth factors...... and advanced glycation end products (AGE peptides). METHODS: IRMA 2 was a 2-year multicentre, randomized, double-blind trial comparing irbesartan (150 and 300 mg once daily) versus placebo. The primary end-point was time to onset of diabetic nephropathy. Samples from a subgroup from the placebo and the 300 mg...... and vWf predicted the end-point. In addition, endothelial Z-score was associated with progression of albuminuria (p = 0.038). CONCLUSION: Endothelial dysfunction and possibly inflammation are novel predictors of progression to diabetic nephropathy in patients with type 2 diabetes and microalbuminuria...

269. Veinte años de experiencia con homoinjertos vasculares criopreservados en la infección vascular

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E. Quintana

2012-04-01

Conclusiones: Este estudio a largo plazo contribuye a mantener la indicación para el implante de homoinjertos vasculares criopreservados en las infecciones vasculares. Los resultados demuestran un comportamiento satisfactorio en esta población multimórbida.

VE-Cadherin–Mediated Epigenetic Regulation of Endothelial Gene Expression

Science.gov (United States)

Morini, Marco F.; Giampietro, Costanza; Corada, Monica; Pisati, Federica; Lavarone, Elisa; Cunha, Sara I.; Conze, Lei L.; O’Reilly, Nicola; Joshi, Dhira; Kjaer, Svend; George, Roger; Nye, Emma; Ma, Anqi; Jin, Jian; Mitter, Richard; Lupia, Michela; Cavallaro, Ugo; Pasini, Diego; Calado, Dinis P.

2018-01-01

Rationale: The mechanistic foundation of vascular maturation is still largely unknown. Several human pathologies are characterized by deregulated angiogenesis and unstable blood vessels. Solid tumors, for instance, get their nourishment from newly formed structurally abnormal vessels which present wide and irregular interendothelial junctions. Expression and clustering of the main endothelial-specific adherens junction protein, VEC (vascular endothelial cadherin), upregulate genes with key roles in endothelial differentiation and stability. Objective: We aim at understanding the molecular mechanisms through which VEC triggers the expression of a set of genes involved in endothelial differentiation and vascular stabilization. Methods and Results: We compared a VEC-null cell line with the same line reconstituted with VEC wild-type cDNA. VEC expression and clustering upregulated endothelial-specific genes with key roles in vascular stabilization including claudin-5, vascular endothelial-protein tyrosine phosphatase (VE-PTP), and von Willebrand factor (vWf). Mechanistically, VEC exerts this effect by inhibiting polycomb protein activity on the specific gene promoters. This is achieved by preventing nuclear translocation of FoxO1 (Forkhead box protein O1) and β-catenin, which contribute to PRC2 (polycomb repressive complex-2) binding to promoter regions of claudin-5, VE-PTP, and vWf. VEC/β-catenin complex also sequesters a core subunit of PRC2 (Ezh2 [enhancer of zeste homolog 2]) at the cell membrane, preventing its nuclear translocation. Inhibition of Ezh2/VEC association increases Ezh2 recruitment to claudin-5, VE-PTP, and vWf promoters, causing gene downregulation. RNA sequencing comparison of VEC-null and VEC-positive cells suggested a more general role of VEC in activating endothelial genes and triggering a vascular stability-related gene expression program. In pathological angiogenesis of human ovarian carcinomas, reduced VEC expression paralleled decreased

Total hip and knee replacement surgery results in changes in leukocyte and endothelial markers

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Maclean Kirsty M

2010-01-01

Full Text Available Abstract Background It is estimated that over 8 million people in the United Kingdom suffer from osteoarthritis. These patients may require orthopaedic surgical intervention to help alleviate their clinical condition. Investigations presented here was to test the hypothesis that total hip replacement (THR and total knee replacement (TKR orthopaedic surgery result in changes to leukocyte and endothelial markers thus increasing inflammatory reactions postoperatively. Methods During this 'pilot study', ten test subjects were all scheduled for THR or TKR elective surgery due to osteoarthritis. Leukocyte concentrations were measured using an automated full blood count analyser. Leukocyte CD11b (Mac-1 and CD62L cell surface expression, intracellular production of H2O2 and elastase were measured as markers of leukocyte function. Von Willebrand factor (vWF and soluble intercellular adhesion molecule-1 (sICAM-1 were measured as markers of endothelial activation. Results The results obtained during this study demonstrate that THR and TKR orthopaedic surgery result in similar changes of leukocyte and endothelial markers, suggestive of increased inflammatory reactions postoperatively. Specifically, THR and TKR surgery resulted in a leukocytosis, this being demonstrated by an increase in the total leukocyte concentration following surgery. Evidence of leukocyte activation was demonstrated by a decrease in CD62L expression and an increase in CD11b expression by neutrophils and monocytes respectively. An increase in the intracellular H2O2 production by neutrophils and monocytes and in the leukocyte elastase concentrations was also evident of leukocyte activation following orthopaedic surgery. With respect to endothelial activation, increases in vWF and sICAM-1 concentrations were demonstrated following surgery. Conclusion In general it appeared that most of the leukocyte and endothelial markers measured during these studies peaked between days 1

Delayed treatment with ADAMTS13 ameliorates cerebral ischemic injury without hemorrhagic complication.

Science.gov (United States)

Nakano, Takafumi; Irie, Keiichi; Hayakawa, Kazuhide; Sano, Kazunori; Nakamura, Yoshihiko; Tanaka, Masayoshi; Yamashita, Yuta; Satho, Tomomitsu; Fujioka, Masayuki; Muroi, Carl; Matsuo, Koichi; Ishikura, Hiroyasu; Futagami, Kojiro; Mishima, Kenichi

2015-10-22

Tissue plasminogen activator (tPA) is the only approved therapy for acute ischemic stroke. However, delayed tPA treatment increases the risk of cerebral hemorrhage and can result in exacerbation of nerve injury. ADAMTS13, a von Willebrand factor (VWF) cleaving protease, has a protective effect against ischemic brain injury and may reduce bleeding risk by cleaving VWF. We examined whether ADAMTS13 has a longer therapeutic time window in ischemic stroke than tPA in mice subjected to middle cerebral artery occlusion (MCAO). ADAMTS13 (0.1mg/kg) or tPA (10mg/kg) was administered i.v., immediately after reperfusion of after 2-h or 4-h MCAO for comparison of the therapeutic time windows in ischemic stroke. Infarct volume, hemorrhagic volume, plasma high-mobility group box1 (HMGB1) levels and cerebral blood flow were measured 24h after MCAO. Both ADAMTS13 and tPA improved the infarct volume without hemorrhagic complications in 2-h MCAO mice. On the other hand, ADAMTS13 reduced the infarct volume and plasma HMGB1 levels, and improved cerebral blood flow without hemorrhagic complications in 4-h MCAO mice, but tPA was not effective and these animals showed massive intracerebral hemorrhage. These results indicated that ADAMTS13 has a longer therapeutic time window in ischemic stroke than tPA, and ADAMTS13 may be useful as a new therapeutic agent for ischemic stroke. Copyright © 2015 Elsevier B.V. All rights reserved.

Электронный учебник как одно из средств обучения иностранному языку

OpenAIRE

Чубарова, Е.

2014-01-01

Specifi cs of teaching foreign languages with the use of multime- dia teaching tools like e-books in accordance with principles of informational and educational space are considered. Advantages and disadvantages of e-books as compared to printed text books are explored

Evaluating prediction strategies for identification of T cell responsive mutation-derived neoepitopesin cancer

DEFF Research Database (Denmark)

Andersen, Malene Rask; Bjerregaard, Anne-Mette; Fugmann, T.

2016-01-01

patients. We investigated the T cell recognition of these personalized peptide libraries using a new technology based on DNA-barcode labeled MHC multimers to detect multiple, potentially > 1000, different neoepitope specific T cell populations in a single sample. Through this unbiased comparison, we...

Functional and Histological Evaluation following Canine Vocal Fold Reconstruction Using Composite Thyroid Ala Perichondrium Flaps.

Science.gov (United States)

Hoffman, Matthew R; Glab, Rachel; Gunderson, McLean; Maytag, Allison L; Yang, David T; Jiang, Jack J; Dailey, Seth H

2015-07-01

We evaluated the effects of vocal fold reconstruction using a composite thyroid ala perichondrium flap (CTAP) after unilateral vocal fold stripping in beagles. We hypothesized that CTAP would improve glottic closure, decrease phonation threshold pressure, and decrease perturbation. In addition, vocal folds with CTAP would exhibit neovascularization and fat with increased von Willebrand factor (vWF) and smooth muscle actin (SMA), reflecting neoangiogenesis and flap viability. Randomized controlled trial using beagles. University laboratory. Ten beagles underwent unilateral vocal fold stripping. Dogs in the scar-only group (n = 5) were sacrificed at 1 month. Dogs in the CTAP group (n = 5) underwent ipsilateral reconstruction with CTAP at 1 month and were sacrificed at 2 months. Excised larynx experiments evaluated vocal fold vibration using aerodynamic, acoustic, and mucosal wave measurements. Qualitative evaluation of vocal fold morphology and quantitative analysis of elastin, collagen, glycosaminoglycans, vWF, SMA, and hyaluronic acid were performed. Phonation threshold pressure (P = .005), percent jitter (P = .010), percent shimmer (P = .007), and open quotient (P = .007) were lower in the CTAP group. Neovascularization (P = .0079) and fat (P = .1667) occurred more with CTAP, although the difference in fat was not significant. von Willebrand factor was higher with CTAP vs contralateral normal fold (P = .110), although not statistically significant. Smooth muscle actin was higher with CTAP vs contralateral normal fold (P = .038) and scarred vocal folds (P = .022). Composite thyroid ala perichondrium flap restored glottic closure and vibratory periodicity following vocal fold scarring. Additional investigation on biologic response is warranted. Composite thyroid ala perichondrium flap offers an autologous, vascularized implant that can improve both vocal fold structure and function. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2015.

The angiogenic behaviors of human umbilical vein endothelial cells (HUVEC) in co-culture with osteoblast-like cells (MG-63) on different titanium surfaces.

Science.gov (United States)

Shi, Bin; Andrukhov, Oleh; Berner, Simon; Schedle, Andreas; Rausch-Fan, Xiaohui

2014-08-01

Interaction between osteogenesis and angiogenesis plays an important role in implant osseointegration. In the present study we investigated the influence of titanium surface properties on the angiogenic behaviors of endothelial cells grown in direct contact co-culture with osteoblasts. Human umbilical vein endothelial cells (HUVECs) and osteoblast-like cells (MG-63 cells) were grown in direct co-culture on the following titanium surfaces: acid-etched (A), hydrophilic A (modA), coarse-gritblasted and acid-etched (SLA) and hydrophilic SLA (SLActive). Cell proliferation was evaluated by cell counting combined with flow cytometry. The expression of von Willebrand Factor (vWF), thrombomodulin (TM), endothelial cell protein C receptor (EPCR), E-Selectin, as well as vascular endothelial growth factor (VEGF) receptors Flt-1 and KDR in HUVECs and VEGF in MG-63 were measured by qPCR. The dynamic behavior of endothelial cells was recorded by time-lapse microscopy. Proliferation of HUVECs was highest on A, followed by SLA, modA and SLActive surfaces. The expression of vWF, TM, EPCR, E-Selectin and Flt-1 in HUVECs was significantly higher on A than on all other surfaces. The expression of KDR in HUVECs grown on A surface was below detection limit. VEGF expression in MG-63 cells was significantly higher on SLActive vs SLA and modA vs A surfaces. Time-lapse microscopy revealed that HUVECs moved quickest and formed cell clusters earlier on A surface, followed by SLA, modA and SLActive surface. In co-culture conditions, proliferation and expression of angiogenesis associated genes in HUVECs are promoted by smooth hydrophobic Ti surface, which is in contrast to previous mono-culture studies. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Transcriptomics of maternal and fetal membranes can discriminate between gestational-age matched preterm neonates with and without cognitive impairment diagnosed at 18-24 months.

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Athina Pappas

Full Text Available Neurocognitive impairment among children born preterm may arise from complex interactions between genes and the intra-uterine environment.(1 To characterize the transcriptomic profiles of chorioamniotic membranes in preterm neonates with and without neurocognitive impairment via microarrays and (2 to determine if neonates with neurocognitive impairment can be identified at birth.A retrospective case-control study was conducted to examine the chorioamniotic transcriptome of gestational-age matched very preterm neonates with and without neurocognitive impairment at 18-24 months' corrected-age defined by a Bayley-III Cognitive Composite Score 1.5; 2 Gene ontology analysis indicated enrichment of 19 biological processes and 3 molecular functions; 3PADOG identified 4 significantly perturbed KEGG pathways: oxidative phosphorylation, Parkinson's disease, Alzheimer's disease and Huntington's disease (q-value <0.1; 4 48 of 90 selected differentially expressed genes were confirmed by qRT-PCR, including genes implicated in energy metabolism, neuronal signaling, vascular permeability and response to injury (e.g., up-regulation of SEPP1, APOE, DAB2, CD163, CXCL12, VWF; down-regulation of HAND1, OSR1(p<0.05; and 5 a multi-gene model predicted 18-24 month neurocognitive impairment (using the ratios of OSR1/VWF and HAND1/VWF at birth in a larger, independent set (sensitivity = 74%, at specificity = 83%.Gene expression patterns in the chorioamniotic membranes link neurocognitive impairment in preterm infants to neurodegenerative disease pathways and might be used to predict neurocognitive impairment. Further prospective studies are needed.

Noise-induced hearing loss in construction workers being assessed for hand-arm vibration syndrome.

Science.gov (United States)

House, Ronald A; Sauvé, John T; Jiang, Depeng

2010-01-01

Construction workers are at risk of noise-induced hearing loss (NIHL) but often have no periodic audiometric testing. The participants were construction workers assessed for Hand-Arm Vibration Syndrome (HAVS) at the Occupational Health Clinic, St. Michael's Hospital, Toronto, Ontario. Audiometry was offered and 169 of the 191 workers assessed for HAVS agreed to have the audiometric test. The objective was to examine the prevalence of hearing loss in these 169 workers and to determine the effect on hearing of duration of work in construction (as a proxy for noise exposure) and the severity of vibration white finger (VWF) which previous studies have suggested is a marker for increased individual susceptibility for NIHL. VWF was measured by the Stockholm vascular scale. All participants were men, median age of 57 (range: 28-75), median number of years worked in construction of 35 (range: 4-52). All of the Spearman rank correlations between years worked in construction and the hearing levels at each audiometric frequency were statistically significant (p hearing loss at or above the level at which a workers' compensation pension would be granted in Ontario and the prevalence of this auditory outcome had a statistically significant increase as years worked in construction increased. Multivariate linear regression indicated that VWF also had a statistically significant effect on hearing loss for all audiometric frequencies combined after controlling for years worked in construction. Improved prevention of hearing loss in construction workers is needed.

Shadow-free multimers as extreme-performance meta-atoms

Science.gov (United States)

Safari, M.; Albooyeh, M.; Simovski, C. R.; Tretyakov, S. A.

2018-02-01

We generalize the concept of parity-time symmetric structures with the goal to create meta-atoms exhibiting extraordinary abilities to overcome the presumed limitations in the scattering of overall lossless particles, such as nonzero forward scattering and the equality of scattering and extinction powers for all lossless particles. Although the forward scattering amplitude and the extinction cross section of our proposed meta-atoms vanish, they scatter incident energy into other directions, with controllable directionality. These meta-atoms possess extreme electromagnetic properties not achievable for passive scatterers. As an example, we study meta-atoms consisting of two or three small dipole scatterers. We consider possible microwave realizations in the form of short dipole antennas loaded by lumped elements. The proposed meta-atom empowers extraordinary response of a shadow-free scatterer and theoretically enables most unusual material properties when used as a building block of an artificial medium.

More tricks with tetramers

DEFF Research Database (Denmark)

Dolton, Garry; Tungatt, Katie; Lloyd, Angharad

2015-01-01

Analysis of antigen-specific T-cell populations by flow cytometry with peptide-MHC (pMHC) multimers is now commonplace. These reagents allow the tracking and phenotyping of T cells during infection, autoimmunity and cancer, and can be particularly revealing when used for monitoring therapeutic in...

Severe aortic valve stenosis and nosebleed

NARCIS (Netherlands)

Schoedel, Johannes; Obergfell, Achim; Maass, Alexander H.; Schodel, Johannes

2007-01-01

Aortic valve stenosis is known to be associated with loss of high molecular von Willebrand multimers. This can lead to gastrointestinal bleeding in patients with gastrointestinal angiodysplasia, the Heyde syndrome. Here we present a case of anaemia and severe epistaxis associated with acquired von

Genetic polymorphisms of hemostatic factors and thrombotic risk in non BCR-ABL myeloproliferative neoplasms: A pilot study

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Dambrauskienė R

2017-06-01

Full Text Available The most important complications of Philadelphianegagive (non BCR-ABL myeloproliferative neoplasms (MPNs are vascular events. Our aim was to evaluate the effects of single nucleotide polymorphisms (SNPs, platelet glycoproteins (GPs (Ia/IIa, Ibα, IIb/IIIa and VI, von Willebrand factor (vWF, coagulation factor VII (FVII, β-fibrinogen, and the risk of thrombosis in patients with non BCR-ABL MPNs at the Lithuanian University of Health Sciences. Kaunas, Lithuania. Genotyping was done for 108 patients. The TT genotype of the GP Ia/IIa c.807C>T polymorphism was more frequently found in the group of MPN patients with arterial thrombosis compared to MPN patients who were thrombosis-free [26.5 vs. 11.5%, p = 0.049; odds ratio (OR 2.68; 95% confidence interval (95% CI 1.01-7.38]. The CT genotype of the β-fibrinogen c.-148C>T polymorphism occurred more frequently in MPN patients with arterial, and total thrombosis compared to the wild or homozygous genotype (57.7 vs. 40.0 vs. 12.5%; p = 0.027, (64.7 vs. 44.4 vs. 25%; p = 0.032, respectively. The carrier state for the c.-323P10 variant of FVII SNP (summation of P10/10 and P0/10 was more frequent in MPN patients with thrombosis compared to the wild-type genotype carriers (71.4 vs. 43.4%; p = 0.049; OR 3.26; 95% CI 1.01-11.31. The coexistence of heterozygous β-fibrinogen c.-148C>T and FVII c.-323P0/10 SNP, increased the risk of arterial thrombosis (21.1 vs. 3.7%, p = 0.008; OR 6.93; 95% CI 1.38-34.80. The TT genotype of GP Ia/IIa c.807C>T, the CT genotype of β-fibrinogen c.-148C>T and FVII c.-323P0/10 SNP could be associated with risk of thrombosis in MPN patients.

Predictive value of ovarian stroma measurement for cardiovascular risk in polycyctic ovary syndrome: a case control study

Directory of Open Access Journals (Sweden)

Loverro Giuseppe

2010-11-01

Full Text Available Abstract Background To verify the feasibility of ovarian stromal evaluation and correlate ovarian parameteres (echogenicity and volume with hyperandrogenism, and both cardiovascular and metabolic risk factors in PCOS. Methods Twenty four young PCOS patients and twelve age-matched control women were enrolled. Diagnosis of PCOS was based on the Rotterdam criteria. Ultrasound ovarian study included ovarian volume, stromal volume, stromal area and stromal area/total ovarian area ratio (S/A. Concerning hormones, insulin, LH, FSH, estradiol, androstenedione, testosterone, DHEAS, 17-hydroxy-progesterone, and SHBG were measured during the early follicular phase (days 2-5. Cardiovascular risk factors were represented by fasting plasma levels of glucose, lipids (total and HDL-cholesterol, plasminogen activator inhibitor 1 (PAI-1, von-Willebrand factor (vWF, and adiponectin. Carotid intima-media thickness (C-IMT was measured as a parameter of cardiovascular risk. Results A positive correlation between the S/A ratio and plasma levels of testosterone (p Conclusions This study shows that the ultrasound measurement of ovarian stroma is a predicting factor of hyperandrogenism degree, prothrombotic factors and cardiovascular risk in patients with PCOS.

Plasminogen activator inhibitor-1 polymers, induced by inactivating amphipathic organochemical ligands

DEFF Research Database (Denmark)

Pedersen, Katrine E; Einholm, Anja P; Christensen, Anni

2003-01-01

Negatively charged organochemical inactivators of the anti-proteolytic activity of plasminogen activator inhibitor-1 (PAI-1) convert it to inactive polymers. As investigated by native gel electrophoresis, the size of the PAI-1 polymers ranged from dimers to multimers of more than 20 units. As com...

Nucleic acid binding properties and intermediates of HCV core protein multimerization in Pichia pastoris

International Nuclear Information System (INIS)

Acosta-Rivero, Nelson; Rodriguez, Armando; Musacchio, Alexis; Falcon, Viviana; Suarez, Viana M.; Chavez, Liudmila; Morales-Grillo, Juan; Duenas-Carrera, Santiago

2004-01-01

Little is known about the in vivo assembly pathway or structure of the hepatitis C virus nucleocapsid. In this work the intermediates of HCcAg multimerization in Pichia pastoris cells and the nucleic acid binding properties of structured nucleocapsid-like particles (NLPs) were studied. Extensive cross-linking was observed for HCcAg after glutaraldehyde treatment. Data suggest that HCcAg exists in dimeric forms probably representing P21-P21, P21-P23, and P23-P23 dimers. In addition, the presence of HCcAg species that might represent trimers and multimers was observed. After sucrose equilibrium density gradient purification and nuclease digestion, NLPs were shown to contain both RNA and DNA molecules. Finally, the analysis by electron microscopy indicated that native NLPs were resistant to nuclease treatment. These results indicated that HCcAg assembles through dimers, trimers, and multimers' intermediates into capsids in P. pastoris cells. Assembly of NLPs in its natural environment might confer stability to these particles by adopting a compact structure

Regional assignment of seven loci to 12p 13. 2-pter by PCR analysis of somatic cell hybrids containing the der(12) or the der(X) chromosome from a mesothelioma showing t(X; 12)(q22; p13)

Energy Technology Data Exchange (ETDEWEB)

Aerssens, J.; Chaffanet, M.; Baens, M.; Matthijs, G.; Van Den Berche, H.; Cassiman, J.J.; Marynen, P. (Arthritis and Metabolic Bone Disease Research Unit, Leuven (Belgium))

1994-03-01

Two somatic cell hybrids containing the der(12) or the der(X) from a mesothelioma with a translocation t(X;12) (q22;p13) as the only chromosomal change were generated to characterize the region of 12p12 containing the translocation breakpoint. Fluorescence in situ hybridization analysis showed the breakpoint on chromosome 12 to occur between VWF and D12S158. On the linkage map developed by J. Weissenbach et al., the breakpoints were located between DXS1106 and DCS1001 on chromosome X. PCR analysis based on genomic sequences, with DNA from both somatic cell hybrids, enabled mapping of CACNL1A1, FGF6, D12S370, D12S38OE, D12S381E, and D12S382E distally to the 12p13 breakpoint and to VWF. 11 refs., 2 figs., 1 tab.

Platelet degranulation and monocyte-platelet complex formation are increased in the acute and convalescent phases after ischaemic stroke or transient ischaemic attack.

LENUS (Irish Health Repository)

McCabe, Dominick J H

2004-06-01

Flow cytometric studies suggest that platelets are activated in ischaemic stroke or transient ischaemic attack (TIA). However, few studies have measured circulating leucocyte-platelet complexes in this patient population. Whole blood flow cytometry was used to quantify the expression of CD62P-, CD63-, and PAC1-binding, and the percentages of leucocyte-platelet complexes in acute (1-27 d, n = 79) and convalescent (79-725 d, n = 70) ischaemic cerebrovascular disease (CVD) patients compared with controls without CVD (n = 27). We performed a full blood count, and measured plasma levels of soluble P-selectin, soluble E-selectin, and von Willebrand factor antigen (VWF:Ag) as additional markers of platelet and\\/or endothelial cell activation. The median percentage CD62P expression and the median percentage monocyte-platelet complexes were higher in both acute and convalescent CVD patients than controls (P <\\/= 0.02). The mean white cell count and mean VWF:Ag levels were significantly elevated in the acute and convalescent phases after ischaemic stroke or TIA (P <\\/= 0.02). Otherwise, there was no significant increase in any other marker of platelet or endothelial activation in CVD patients. There was a positive correlation between the percentage expression of CD62P and the percentages of both neutrophil-platelet and monocyte-platelet complexes in the acute phase, and the percentages of all leucocyte-platelet complexes in the convalescent phase after ischaemic CVD. This study provides evidence for ongoing excessive platelet and\\/or endothelial activation in ischaemic CVD patients despite treatment with antithrombotic therapy.

Development of an epitope panel for consistent identification of antigen-specific T-cells in humans

DEFF Research Database (Denmark)

Fløe, Andreas; Løppke, Caroline; Hilberg, Ole

2017-01-01

Objective We aimed to establish a panel of MHC-peptide multimers suitable as a positive control in detection of HLA A*0201 restricted antigen specific T-cells (ASTC) by flow cytometry. Materials and methods MHC Dextramers were loaded with HLA A*0201 binding peptides from viral antigens and melano...

Developing Modular and Adaptable Courseware Using TeachML.

Science.gov (United States)

Wehner, Frank; Lorz, Alexander

This paper presents the use of an XML grammar for two complementary projects--CHAMELEON (Cooperative Hypermedia Adaptive MultimEdia Learning Objects) and EIT (Enabling Informal Teamwork). Areas of applications are modular courseware documents and the collaborative authoring process of didactical units. A number of requirements for a suitable…

Digital signage sobre IP

OpenAIRE

Casademont Filella, Albert

2012-01-01

Projecte que versa sobre el disseny i la implementació d'un sistema de Digital Signage (Cartelleria Digital) sobre IP, creant un gestor que permeti controlar de forma remota tot un conjunt de petits dispositius connectats a pantalles que emeten continguts multimèdia com vídeos, imatges, feeds rss...

Traces of pFc' in IVIG interact with human IgG Fc domains and counteract aggregation

NARCIS (Netherlands)

Rispens, Theo; Himly, Martin; Ooievaar-de Heer, Pleuni; den Bleker, Tamara H.; Aalberse, Rob C.

2010-01-01

To prevent multimer formation, intravenous immunoglobulin (IVIG) is often treated with traces of pepsin. So far, the mechanism behind this treatment has been unclear. Recently, we reported that human IgG4 binds other IgG molecules via Fc-Fc interactions. Here we show that IVIG treated with traces of

LITERATURA E MULTIMEIOS: UMA PROPOSTA PEDAGÓGICA

OpenAIRE

Eric Zorob; Geruza Zelnys de Almeida

2017-01-01

O artigo discute o ensino da literatura aliado ao aprendizado das linguagens multimídias e apresenta uma atividade realizada com alunos do Ensino Médio, fundamentada em teóricos da literatura, semiótica e comunicação: a tradução de músicas em videoclipes.

Assembly and activation of alternative complement components on endothelial cell-anchored ultra-large von Willebrand factor links complement and hemostasis-thrombosis.

Directory of Open Access Journals (Sweden)

Nancy A Turner

Full Text Available Vascular endothelial cells (ECs express and release protein components of the complement pathways, as well as secreting and anchoring ultra-large von Willebrand factor (ULVWF multimers in long string-like structures that initiate platelet adhesion during hemostasis and thrombosis. The alternative complement pathway (AP is an important non-antibody-requiring host defense system. Thrombotic microangiopathies can be associated with defective regulation of the AP (atypical hemolytic-uremic syndrome or with inadequate cleavage by ADAMTS-13 of ULVWF multimeric strings secreted by/anchored to ECs (thrombotic thrombocytopenic purpura. Our goal was to determine if EC-anchored ULVWF strings caused the assembly and activation of AP components, thereby linking two essential defense mechanisms.We quantified gene expression of these complement components in cultured human umbilical vein endothelial cells (HUVECs by real-time PCR: C3 and C5; complement factor (CF B, CFD, CFP, CFH and CFI of the AP; and C4 of the classical and lectin (but not alternative complement pathways. We used fluorescent microscopy, monospecific antibodies against complement components, fluorescent secondary antibodies, and the analysis of >150 images to quantify the attachment of HUVEC-released complement proteins to ULVWF strings secreted by, and anchored to, the HUVECs (under conditions of ADAMTS-13 inhibition. We found that HUVEC-released C4 did not attach to ULVWF strings, ruling out activation of the classical and lectin pathways by the strings. In contrast, C3, FB, FD, FP and C5, FH and FI attached to ULVWF strings in quantitative patterns consistent with assembly of the AP components into active complexes. This was verified when non-functional FB blocked the formation of AP C3 convertase complexes (C3bBb on ULVWF strings.AP components are assembled and activated on EC-secreted/anchored ULVWF multimeric strings. Our findings provide one possible molecular mechanism for clinical

Ferramenta de autoria multimídia para ensino de língua estrangeira em ambiente multiagente Multimedia authorship tool for the teaching of foreign languages in a multi-agent environment

Directory of Open Access Journals (Sweden)

Adroaldo Guimarães Rossetti

2009-04-01

Full Text Available A comunicação é essencial nas atividades do mundo globalizado, onde conhecimento e tecnologia são a chave do progresso. Dominar outros idiomas nesse cenário é vital para a sustentação das pessoas no exercício de suas atividades. O sistema de ensino de línguas estrangeiras no Brasil, tanto nas escolas públicas quanto em parte das escolas particulares, não oferece condições para que as pessoas adquiram conhecimentos sólidos de língua estrangeira, conforme suas potencialidades e disponibilidades de tempo, sem prejuízo de outras atividades que exerçam no seu cotidiano. O objetivo deste artigo é apresentar uma ferramenta de autoria multimídia para ensino de língua estrangeira, disponível continuamente na Internet, que possa ser acessada de qualquer local e a qualquer momento. A ferramenta será construída baseada em arquitetura multiagente, constituindo um ambiente compartilhado semelhante à cooperação entre pessoas, cumprindo eficazmente a tarefa de ensino. Os idiomas, inicialmente inglês e francês, constarão de três módulos: básico, intermediário e avançado. Após ser disponibilizada na Web, a ferramenta será validada com base na crítica dos usuários por cerca de seis a doze meses e será avaliada periodicamente pelos gestores do programa. A ferramenta propiciará o acesso ao aprendizado eficaz de idiomas estrangeiros a quaisquer interessados, de acordo com suas potencialidades, seus interesses e tempo disponível.Communication is essential in the activities of a globalized world in which knowledge and technology are the keys to progress. In this scenario, having command of other languages is a vital support for people in their activities. The system for teaching foreign languages in Brazil, both in public schools and in part of the private institutions, fails to offer the basic conditions for people to acquire solid knowledge of a foreign language, according to their potential and time availability, and without

Profils d’apprentissage et représentations dans l’apprentissage des langues en environnement multimédia. Résultats d’une enquête en contexte universitaire. Learner profiles and attitudes in foreign language learning in a multimedia environment. Results of a survey conducted in a higher education context.

Directory of Open Access Journals (Sweden)

Joseph Rézeau

1999-06-01

Full Text Available Dans le domaine de l’apprentissage, les profils d’apprentissage et les représentations des apprenants jouent un rôle fondamental. La recherche exposée dans cet article met en évidence des différences sensibles de profil d’apprentissage des langues chez des étudiants spécialisés en langues d’une part et des étudiants d’autres disciplines d’autre part. Elle montre également que les représentations de l’apprentissage des langues et celles des Technologies de l’Information et de la Communication (TIC chez ces deux populations sont des représentations sociales, qui montrent un recouvrement entre les deux domaines étudiés. Enfin, une étude longitudinale d’un échantillon de la population étudiée montre que les profils d’apprentissage et les représentations sont susceptibles d’évolution. La question reste posée de l’influence de l’environnement multimédia d’apprentissage de la langue sur cette évolution constatée.In the field of learning, the learners’ attitudes and representations play a fundamental role. The research presented in this article shows significant differences in the language learning profiles of university students specialised in languages on the one hand and specialists of other disciplines on the other hand. Our research also shows that the representations of language learning and the representations of the Information and Communication Technologies (ICT held by the subjects in these two populations are social representations, showing overlap between the two domains studied. Finally, a longitudinal study of a sample of the population under review shows that both learners’ profiles and representations are open to evolution. The question remains of the influence exerted by the multimedia language learning environment over the said evolution.

The ubiquitin-proteasome system

Indian Academy of Sciences (India)

... the discovery of protein ubiquitination has led to the recognition of cellular proteolysis as a central area of research in biology. Eukaryotic proteins targeted for degradation by this pathway are first 'tagged' by multimers of a protein known as ubiquitin and are later proteolyzed by a giant enzyme known as the proteasome.

T cells reactive with HLA-A*0201 peptides from the histone demethylase JARID1B are found in the circulation of breast cancer patients.

Science.gov (United States)

Coleman, Julia A; Correa, Isabel; Cooper, Lucienne; Bohnenkamp, Hermann R; Poulsom, Richard; Burchell, Joy M; Taylor-Papadimitriou, Joyce

2011-05-01

The nuclear protein PLU-1/JARID1B/KDM5 is widely expressed in breast cancers while showing highly restricted expression in normal adult tissues. To investigate whether JARID1B is a potential target antigen for immunotherapy of breast cancer, we have analyzed the responses of CD8(+) T cells to JARID1B HLA-A*0201 peptides in vitro and used peptide multimers to detect the presence of JARID1B reactive T cells in the circulation of breast cancer patients. Peptides were selected using two web-based algorithms: criteria for inclusion being a high score in both prediction algorithms, and nonhomology with retinoblastoma binding protein-2 (RBP2/JARID1A/KDM5A). A 65-peptide panel was selected and assayed for binding strength by competition assay to obtain the IC(50). The immunogenicity in vitro of these peptides was assessed by T cell stimulation experiments, using autologous dendritic cells as APCs in the first rounds followed by autologous lymphoblasts. Fourteen of the peptides assayed produced cultures having >2% of the CD8(+) cells being IFN-γ(+) after 3-6 rounds of stimulation. An HLA-A*0201 cell line could activate the specific T cells if pulsed with peptide, but endogenous peptide levels were insufficient for activation. Nevertheless, multimer staining of circulating T cells from breast cancer patients showed a significantly higher percentage of multimer positive CD8(+) T cells, as compared to healthy adults for two of three JARID1B epitopes tested. One of these, peptide 73 (QLYALPCVL), was analyzed for memory phenotype, and found to have a significantly higher proportion of central memory T cells than the control group, demonstrating a previous exposure to the peptide. Copyright © 2011 UICC.

LITERATURA E MULTIMEIOS: UMA PROPOSTA PEDAGÓGICA

Directory of Open Access Journals (Sweden)

Eric Zorob

2017-03-01

Full Text Available O artigo discute o ensino da literatura aliado ao aprendizado das linguagens multimídias e apresenta uma atividade realizada com alunos do Ensino Médio, fundamentada em teóricos da literatura, semiótica e comunicação: a tradução de músicas em videoclipes.

GPIHBP1 Missense Mutations Often Cause Multimerization of GPIHBP1 and Thereby Prevent Lipoprotein Lipase Binding

DEFF Research Database (Denmark)

Beigneux, Anne P; Fong, Loren G; Bensadoun, Andre

2015-01-01

lacked the ability to bind LPL but had a reduced propensity for forming dimers or multimers, suggesting that W109 might play a more direct role in binding LPL. In support of that idea, replacing W109 with any of 8 other amino acids abolished LPL binding-and often did so without promoting the formation...

Pulse EPR distance measurements to study multimers and multimerisation

Science.gov (United States)

Ackermann, Katrin; Bode, Bela E.

2018-06-01

Pulse dipolar electron paramagnetic resonance (PD-EPR) has become a powerful tool for structural biology determining distances on the nanometre scale. Recent advances in hardware, methodology, and data analysis have widened the scope to complex biological systems. PD-EPR can be applied to systems containing lowly populated conformers or displaying large intrinsic flexibility, making them all but intractable for cryo-electron microscopy and crystallography. Membrane protein applications are of particular interest due to the intrinsic difficulties for obtaining high-resolution structures of all relevant conformations. Many drug targets involved in critical cell functions are multimeric channels or transporters. Here, common approaches for introducing spin labels for PD-EPR cause the presence of more than two electron spins per multimeric complex. This requires careful experimental design to overcome detrimental multi-spin effects and to secure sufficient distance resolution in presence of multiple distances. In addition to obtaining mere distances, PD-EPR can also provide information on multimerisation degrees allowing to study binding equilibria and to determine dissociation constants.

Von Willebrand's disease: case report and review of literature ...

African Journals Online (AJOL)

By taking a clinical history of bleeding (mucocutaneous bleeding symptoms suggestive of a primary haemostatic disorder, a quantitative or qualitative abnormality of VWF is possible) it is important to think about VWD and to make the appropriate diagnosis. If the VWD is suspected diagnostic tests should include an activated ...

Upcyte® Microvascular Endothelial Cells Repopulate Decellularized Scaffold

Science.gov (United States)

Dally, Iris; Hartmann, Nadja; Münst, Bernhard; Braspenning, Joris; Walles, Heike

2013-01-01

A general problem in tissue engineering is the poor and insufficient blood supply to guarantee tissue cell survival as well as physiological tissue function. To address this limitation, we have developed an in vitro vascularization model in which a decellularized porcine small bowl segment, representing a capillary network within a collagen matrix (biological vascularized scaffold [BioVaSc]), is reseeded with microvascular endothelial cells (mvECs). However, since the supply of mvECs is limited, in general, and as these cells rapidly dedifferentiate, we have applied a novel technology, which allows the generation of large batches of quasi-primary cells with the ability to proliferate, whilst maintaining their differentiated functionality. These so called upcyte mvECs grew for an additional 15 population doublings (PDs) compared to primary cells. Upcyte mvECs retained endothelial characteristics, such as von Willebrandt Factor (vWF), CD31 and endothelial nitric oxide synthase (eNOS) expression, as well as positive Ulex europaeus agglutinin I staining. Upcyte mvECs also retained biological functionality such as tube formation, cell migration, and low density lipoprotein (LDL) uptake, which were still evident after PD27. Initial experiments using MTT and Live/Dead staining indicate that upcyte mvECs repopulate the BioVaSc Scaffold. As with conventional cultures, these cells also express key endothelial molecules (vWF, CD31, and eNOS) in a custom-made bioreactor system even after a prolonged period of 14 days. The combination of upcyte mvECs and the BioVaSc represents a novel and promising approach toward vascularizing bioreactor models which can better reflect organs, such as the liver. PMID:22799502

Neutrophil extracellular traps promote deep vein thrombosis in mice

Science.gov (United States)

Brill, A.; Fuchs, T.A.; Savchenko, A.S.; Thomas, G.M.; Martinod, K.; De Meyer, S.F.; Bhandari, A.A.; Wagner, D.D.

2011-01-01

Summary Background Upon activation, neutrophils can release nuclear material known as neutrophil extracellular traps (NETs), which were initially described as a part of antimicrobial defense. Extracellular chromatin was recently reported to be pro-thrombotic in vitro and to accumulate in plasma and thrombi of baboons with experimental deep vein thrombosis (DVT). Objective To explore the source and role of extracellular chromatin in DVT. Methods We used an established murine model of DVT induced by flow restriction (stenosis) in the inferior vena cava (IVC). Results We demonstrate that the levels of extracellular DNA increase in plasma after 6 h IVC stenosis, compared to sham-operated mice. Immunohistochemical staining revealed the presence of Gr-1-positive neutrophils in both red (RBC-rich) and white (platelet-rich) parts of thrombi. Citrullinated histone H3 (CitH3), an element of NETs’ structure, was present only in the red part of thrombi and was frequently associated with the Gr-1 antigen. Immunofluorescent staining of thrombi showed proximity of extracellular CitH3 and von Willebrand factor (VWF), a platelet adhesion molecule crucial for thrombus development in this model. Infusion of Deoxyribonuclease 1 (DNase 1) protected mice from DVT after 6 h and also 48 h IVC stenosis. Infusion of an unfractionated mixture of calf thymus histones increased plasma VWF and promoted DVT early after stenosis application. Conclusions Extracellular chromatin, likely originating from neutrophils, is a structural part of a venous thrombus and both the DNA scaffold and histones appear to contribute to the pathogenesis of DVT in mice. NETs may provide new targets for DVT drug development. PMID:22044575

Molecular cloning and characterization of rhesus monkey platelet glycoprotein Ibα, a major ligand-binding subunit of GPIb-IX-V complex.

Science.gov (United States)

Qiao, Jianlin; Shen, Yang; Shi, Meimei; Lu, Yanrong; Cheng, Jingqiu; Chen, Younan

2014-05-01

Through binding to von Willebrand factor (VWF), platelet glycoprotein (GP) Ibα, the major ligand-binding subunit of the GPIb-IX-V complex, initiates platelet adhesion and aggregation in response to exposed VWF or elevated fluid-shear stress. There is little data regarding non-human primate platelet GPIbα. This study cloned and characterized rhesus monkey (Macaca Mullatta) platelet GPIbα. DNAMAN software was used for sequence analysis and alignment. N/O-glycosylation sites and 3-D structure modelling were predicted by online OGPET v1.0, NetOGlyc 1.0 Server and SWISS-MODEL, respectively. Platelet function was evaluated by ADP- or ristocetin-induced platelet aggregation. Rhesus monkey GPIbα contains 2,268 nucleotides with an open reading frame encoding 755 amino acids. Rhesus monkey GPIbα nucleotide and protein sequences share 93.27% and 89.20% homology respectively, with human. Sequences encoding the leucine-rich repeats of rhesus monkey GPIbα share strong similarity with human, whereas PEST sequences and N/O-glycosylated residues vary. The GPIbα-binding residues for thrombin, filamin A and 14-3-3ζ are highly conserved between rhesus monkey and human. Platelet function analysis revealed monkey and human platelets respond similarly to ADP, but rhesus monkey platelets failed to respond to low doses of ristocetin where human platelets achieved 76% aggregation. However, monkey platelets aggregated in response to higher ristocetin doses. Monkey GPIbα shares strong homology with human GPIbα, however there are some differences in rhesus monkey platelet activation through GPIbα engagement, which need to be considered when using rhesus monkey platelet to investigate platelet GPIbα function. Copyright © 2014 Elsevier Ltd. All rights reserved.

Genetically modified human bone marrow derived mesenchymal stem cells for improving the outcome of human islet transplantation.

Directory of Open Access Journals (Sweden)

Vaibhav Mundra

Full Text Available The objective of this study was to determine the potential of human bone marrow derived mesenchymal stem cells (hBMSCs as gene carriers for improving the outcome of human islet transplantation. hBMSCs were characterized for the expression of phenotypic markers and transduced with Adv-hVEGF-hIL-1Ra to overexpress human vascular endothelial growth factor (hVEGF and human interleukin-1 receptor antagonist (hIL-1Ra. Human islets were co-cultured with hBMSCs overexpressing hVEGF and hIL-1Ra. Islet viability was determined by membrane fluorescent method and glucose stimulation test. Transduced hBMSCs and human islets were co-transplanted under the kidney capsule of NOD.Cg-Prkdc(scid Il2rg(tm1Wjl /SzJ (NSG diabetic mice and blood glucose levels were measured over time to demonstrate the efficacy of genetically modified hBMSCs. At the end of study, immunofluorescent staining of kidney section bearing islets was performed for insulin and von Willebrand Factor (vWF. hBMSCs were positive for the expression of CD73, CD90, CD105, CD146 and Stro-1 surface markers as determined by flow cytometry. Transduction of hBMSCs with adenovirus did not affect their stemness and differentiation potential as confirmed by mRNA levels of stem cell markers and adipogenic differentiation of transduced hBMSCs. hBMSCs were efficiently transduced with Adv-hVEGF-hIL-1Ra to overexpress hVEGF and hIL-1Ra. Live dead cell staining and glucose stimulation test have shown that transduced hBMSCs improved the viability of islets against cytokine cocktail. Co-transplantation of human islets with genetically modified hBMSCs improved the glycemic control of diabetic NSG mice as determined by mean blood glucose levels and intraperitoneal glucose tolerance test. Immunofluorescent staining of kidney sections was positive for human insulin and vWF. In conclusion, our results have demonstrated that hBMSCs may be used as gene carriers and nursing cells to improve the outcome of islet

Using mass spectrometry and small molecule reagents to detect distinctive structural features of different prion conformations (strains)

Science.gov (United States)

A prion (PrPSc) is a conformer of a normal cellular prion protein (PrPC). Although they are isosequential, PrPSc is an infectious protein able to convert PrPC into the prion conformation and thereby propagate an infection. PrPC is monomeric while PrPSc is a multimer. PrPSc can adopt more than one co...

Some applications of the Faddeev-Yakubovsky equations to the cold-atom physics

International Nuclear Information System (INIS)

Carbonell, J.; Deltuva, A.; Lazauskas, R.

2011-01-01

We present some recent applications of the Faddeev-Yakubovsky equations in describing atomic bound and scattering problems. We consider the scattering of a charged particle X by atomic hydrogen with special interest in X = p,e ± , systems of cold bosonic molecules and the bound and scattering properties of N=3 and N=4 atomic 4 He multimers. (authors)

Jeunes, pauvreté et utilisation des TIC - nouvelles sphères ...

International Development Research Centre (IDRC) Digital Library (Canada)

Les TIC peuvent englober les réseaux sociaux (comme Facebook et Twitter), les communautés virtuelles (comme Idealist et TakingITGlobal) et les plateformes de diffusion de contenu multimédia (comme YouTube, MySpace et Youth Media Exchange Project). Ce projet servira à documenter la manière dont les jeunes ...

Hemostatic System in Chronic Viral Hepatitis

Directory of Open Access Journals (Sweden)

Natalia Borisova

2018-06-01

Full Text Available Hemostasis is balanced by pro- and anticoagulant and pro- and antifibrinolytic factors, most of these being synthesized by the liver. Advanced liver disease is associated with perturbations in the level of these factors due to secretory deficiencies. Thrombocytopenia, reduced levels of factor II-VII-X, and anti-fibrinolytic factors are all features of CHC infection, suggesting hypocoagulability. However, higher concentrations of VWF and factor VIII, as well as lower concentrations of anticoagulant factors including protein C and S, have also been reported in CHC infections, suggesting hypercoagulability. Thus, the hemostatic balance in the patient with liver disease is relatively unstable as evidenced by the occurrence of both bleeding and thrombotic complications in a significant proportion of patients with chronic viral hepatitis. In patients with chronic liver disease (CLD, in whom extremely complex alterations of hemostasis occur, one cannot rely on levels of individual coagulation factors, or on simplified tests of hemostasis such as the PT or APTT to predict the hemostatic status. To determine the hemostatic status in these patients, more complex tests and a more comprehensive overview of the hemostatic changes are required. In connection with the latest studies, a revision of the methods for correction of hemostatic system disorders in patients with acute and chronic liver diseases becomes urgent.

Noise, impulse noise, and other physical factors: combined effects on hearing.

Science.gov (United States)

Pekkarinen, J

1995-01-01

In most of the epidemiologic studies conducted during the last 20 years, impulse noise caused increased risk of hearing loss in comparison to continuous noise with the same acoustical energy. The interaction between noise exposure (broadband at 100 dB(A)) and hand-arm vibration (125 Hz at 2 ms-2 acceleration level) has been proven for people having vibration-induced white finger symptoms. This interaction is evidenced as a permanent hearing loss. However, why the interaction is seen only in people with VWF is not known. The mechanisms may be related to individual susceptibility, and hypotheses are given on the role of the autonomous nervous system regulating the peripheral vascular reaction. Whole-body vibration (2-10 Hz, at 10 ms-2 level) seems to increase the TTS when noise (broadband at 90 dB(A)) is present. This effect is more pronounced at higher temperatures. The hypothermia protects hearing against the effects of noise in animal studies. The interaction between noise and temperature decrease seems obvious in animal studies. Exercise has both increased and decreased the TTS during noise exposure. The effects have been successfully explained as the depression of the stapedius reflex. Thus, less protection against noise is provided for the inner ear in exercise conditions. The increase of the blood temperature also has been suggested to increase noise-induced TTS during exercise. Electromagnetic fields have been found to cause acoustical interactions in the inner ear. Animal studies and human studies have given contradictory results on the effects of magnetic coil devices on hearing. The MR imaging devices produce noise levels of 82-93 dB, which is not sufficient to produce the risk of permanent hearing loss when short exposure durations are taken into consideration. More systematic research is needed with accurately defined electromagnetic characteristics to reveal the potential interactions. The interactions seem to exist, but relatively high levels and

Diagnosis of vascular injuries caused by hand-transmitted vibration.

Science.gov (United States)

Harada, N; Mahbub, M H

2008-04-01

For a reliable objective diagnosis of vascular injuries in hand-arm vibration syndrome (HAVS), the standardized cold provocation tests--finger skin temperature measurement during hand(s) immersion in cold water (FST test) and finger systolic blood pressure measurement during local cold exposure (FSBP test)--are widely used. In recent years there is a growing controversy regarding the diagnostic value of these tests. The aim of this study was to describe particularly the diagnostic performance of FST and FSBP tests, and also to focus on the problems and uncertainties regarding the test conditions and results, in the laboratory diagnosis of vascular injuries caused by hand-transmitted vibration. A review of pertinent published English- and Japanese-language articles and conference proceedings (between 1976 and 2006) was conducted. From the reports with regard to diagnostic significance of the FSBP test, it seems to be an important laboratory test for diagnosing vibration-induced white finger (VWF). On the other hand, despite a large number of research studies with the FST test, there is a lack of data for the standardized FST test, which can confirm the value of it in diagnosing VWF. Moreover, there is no agreement on effective parameter/s to quantify and compare the responses in FST induced by immersion in cold water. While assessing and staging vascular injuries in HAVS, inquiry regarding finger coldness appears to be useful. As there is no single test with satisfactory diagnostic ability for VWF, at present it is reasonable to use the cold provocation tests as a part of the comprehensive approach to evaluate HAVS patients. In addition to the objective methods, the index of finger coldness may be useful while diagnosing the vascular component of HAVS.

Avaliação de habilidades sociais de crianças com um inventário multimídia: indicadores sociométricos associados a freqüência versus dificuldade Evaluation of children’s social skills using a multimedia social skills inventoire: psichometric indexes of frequency versus difficulty

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Zilda Aparecida Pereira Del Prette

2002-06-01

Full Text Available A literatura sobre avaliação da competência social e das habilidades sociais é permeada de resultados controvertidos, provavelmente devidos ao uso de diferentes indicadores, informantes e conceitos norteadores. Dada a relevância dessas questões, em particular da auto-avaliação de crianças, e a relativa escassez de estudos a seu respeito, este artigo relata uma pesquisa que teve por objetivo comparar diferenças e semelhanças em algumas propriedades psicométricas, associadas a indicadores de freqüência e dificuldade de desempenhos sociais obtidos com o "Inventário multimídia de habilidades sociais para crianças" (IMHSC-Del-Prette. O IMHSC-Del-Prette foi aplicado inicialmente a 406 escolares de 7 a 13 anos (média =8, de ambos os sexos, com diferentes graus de dificuldade de aprendizagem, e reaplicado um mês depois com 191 (47% estudantes dessa amostra. Os resultados foram mais favoráveis ao indicador de dificuldade que ao de freqüência nos seguintes aspectos: simetria na distribuição dos escores, consistência interna, correlação entre teste e reteste, índices de discriminação entre itens e escores e estrutura fatorial (quatro ao invés de três fatores. São discutidas as implicações metodológicas e práticas desses resultados, indicando-se novas direções de pesquisa.The field of the social competence and social skills evaluation are permeated of contradictory results, largely associated to the use, in many studies, of different indexes, informers and concepts. Given the relevance and relative scarcity of studies on that subject, in particular about children's self-evaluation, the present paper aims to compare differences and similarities, in some psychometric properties associated to two indicators - frequency and difficulty of skilled social reactions - obtained with a Multimedia Social Skills Inventoire for Children (MUSSIC-Del-Prette. MUSSIC-Del-Prette was applied initially to 406 children of 7 a 13 years old

Clinical aspects of the hand-arm vibration syndrome. A review.

Science.gov (United States)

Pyykkö, I

1986-10-01

At present it seems likely that the different components of the hand-arm vibration syndrome, eg, vibration-induced white finger (VWF), numbing of the hands and arms, muscular fatigue, and occasionally prevalent bone degeneration, may arise independently, and therefore they should be evaluated separately. Evidence of changes caused in the autonomic nervous functions of the body by local vibration is not conclusive. The vascular history should be confirmed objectively with a cold provocation test under laboratory conditions. In individual diagnostics it is useful to record (with modern plethysmographic techniques) the recovery of digital temperature, digital blood pressure, and flow after local cooling. Vibrotactile perception measurement seems to be suitable for group diagnosis. Much of the diagnostic weight for VWF can be obtained from accurate case histories, although, for early changes, the history may be atypical. The lack of simple objective tests for evaluating the hand-arm vibration syndrome makes it difficult to, eg, confirm the history of its different components objectively and estimate the extent of the disability it causes.

Shengui Sansheng San extraction is an angiogenic switch via regulations of AKT/mTOR, ERK1/2 and Notch1 signal pathways after ischemic stroke.

Science.gov (United States)

Liu, Bowen; Luo, Cheng; Zheng, Zhaoguang; Xia, Zhenyan; Zhang, Qian; Ke, Chienchih; Liu, Renshyan; Zhao, Yonghua

2018-05-15

As a traditional Chinese herbal formula, Shengui Sansheng San (SSS) has been employed for stroke treatment more than 300 years. We hypothesize that SSS extraction is an angiogenic switch in penumbra post-stroke, and corresponding mechanisms are investigated. In present study, rats were subjected to permanent middle cerebral artery occlusion model (MCAo) and were treated with low, middle and high doses of SSS extraction. We assessed neurological function and survival rate, and measured infarct volume by 2,3,5-triphenyltetrazolium chloride staining on day 7 after ischemia. von Willebrand factor (vWF), stromal cell-derived factor-1 alpha (SDF-1α) /chemokine (C-X-C motif) receptor 4 (CXCR4) axis, vascular endothelial growth factor (VEGF)/VEGF receptor 2 (VEGFR2) as well as protein kinase B (AKT)/mammalian target of rapamycin (mTOR) /hypoxia-inducible factor-1 alpha (HIF-1α), extracellular signal-regulated kinase 1/2 (ERK1/2) and Notch1 signaling pathways were respectively investigated by immunofluorescence assay or western blotting in vivo and oxygen-glucose-deprived (OGD) brain microvascular endothelial cells (BMECs); simultaneously, wound healing of BMECs and tube formation assay were administrated. Compared to MCAo group, SSS extraction could significantly improve neurological functional scores, survival rate and cerebral infarct volume, enhance vWF + vascular density and perimeter, SDF-1α/CXCR4 axis, VEGF expression, as well as activate AKT/mTOR/HIF-1α and ERK1/2 and inhibit Notch1 pathways in penumbra. In vitro, containing SSS extraction serum increased BMEC migration, capillary formation and VEGF expression via up-regulations of AKT/mTOR and ERK1/2 pathways in OGD BMECs, but ERK inhibitor (U0126) reversed the result of VEGF expression in high dose of SSS group. Additionally, VEGFR2 and Notch1 expressions were suppressed by containing SSS extraction serum. All results were in dose dependent manner. Our study firstly demonstrates that SSS extraction is an

Modelos aditivos y multiplicativos en el análisis de matrices multitrazos - multimétodos de cuestionarios de intereses profesionales

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Jacques Ruhel

2009-02-01

Full Text Available The psychologist needs the evaluation of the conceptual validity (convergent and discriminant of psychological constructions, used for describing and explaining the organization of his observations. In this work, we describe two approaches based in latent variables, that can be used for these evaluations. The first one is the first order confirmatory (or restrictive factor analysis; the second one is the direc´-product model where the traits and the methods take effect. The methods are used on a data matrix multitrait and multimethod take effect. The methods are used on a data matrix   multitrait and multimethod obtained on a sample of 189 french high-school students, that responded two questionnaires of  professional interests; a discussion of the results follows. Keywords: conceptual validity, multitrait-multimethod matrices, confirmatoty factor analysis, direct- product model, professional interest.

Evaluation of coagulation factors and platelet function from an off-line modified ultrafiltration technique for post-cardiopulmonary bypass circuit blood recovery.

Science.gov (United States)

Beckmann, S; Lynn, P; Miller, S; Harris, R; DiMarco, R F; Ross, J E

2013-05-01

Modified ultrafiltration (MUF) is a technique that hemoconcentrates residual CPB circuit blood and the patient at the same time. Hemoconcentration and MUF are Class 1-A recommendations in the anesthesia and surgical blood conservation guidelines. This study evaluated the off-line MUF process of the Hemobag (HB, Global Blood Resources, Somers, CT, USA) to quantitate coagulation factor levels, platelet (PLT) count and function in one facility and cellular growth factor concentrations of the final product that were transfused to the patient in another facility In two cardiac surgery facilities, after decannulation, the extracorporeal circuit (ECC) blood from 22 patients undergoing cardiac surgery was processed with the HB device. In eleven patients from the first facility by the study design, blood samples for coagulation factor levels and PLT aggregation were drawn from the reservoir of the MUF device pre- and post-processing. The samples (n = 11) were sent to a reference laboratory where testing for prothrombin time (PT), international normalized ratio (INR), activated partial thromboplastin time (aPTT), reptilase time, fibrinogen, clotting factors II, V, VII, VIII, IX, X, ADAMTS-13, protein C, protein S, antithrombin III, von Willebrand Factor (vWF), and platelet (PLT) aggregation were performed. A portion of the final concentrated HB blood samples (n = 5-10) from the second facility by design were evaluated for transforming and platelet-derived cellular growth factor concentrations. On average, approximately 800 - 2000 mls of whole blood were removed from the ECC post-CPB for processing in the HB device. After processing, there was, on the average, approximately 300 - 950 mls of concentrated whole blood salvaged for reinfusion. The PT and INR were significantly lower in the post-processing product compared to the pre-processing samples while the aPTT times were not significantly different. All coagulation factors and natural anti-coagulants were significantly

Author Details

African Journals Online (AJOL)

Boukelifa, A. Vol 12, No 2 (2002) - Articles L'Impact de l'enseignement à distance (EAD) sur le processus pédagogique de l'intelligence artificielle et du Multimédia Abstract. ISSN: 1111-0015. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's ...

Levels of NT-proBNP, markers of low-grade inflammation, and endothelial dysfunction during spironolactone treatment in patients with diabetic kidney disease

DEFF Research Database (Denmark)

Nielsen, Stine; Schjoedt, Katrine J; Rossing, Kasper

2013-01-01

with spironolactone 25 mg and placebo daily for 60 days.Outcome measures:Changes in inflammatory (hsCRP, s-ICAM, TNFα, IL-6, IL-8, Serum amyloid A, IL1β), endothelial dysfunction (sE-selectin, s-ICAM1, s-VCAM1, VWF, p-selectin, s-thrombomodulin) and NT-proBNP after each treatment period. RESULTS: During...

CD133(+) niches and single cells in glioblastoma have different phenotypes

DEFF Research Database (Denmark)

Christensen, Karina; Schrøder, Henrik Daa; Kristensen, Bjarne Winther

2011-01-01

with CD133 and the candidate stem cell markers Sox2, Bmi-1, EGFR, podoplanin and nestin, the proliferation marker Ki67 and the endothelial cell markers CD31, CD34, and VWF. Cell counting showed that the CD133(+) cells in the niches had a significantly higher expression of Sox2, EGFR and nestin compared...

NETosis before and after Hyperglycemic Control in Type 2 Diabetes Mellitus Patients.

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Agostina Carestia

Full Text Available Diabetes is characterized by chronic inflammation, endothelial dysfunction, increased risk of infections and early cardiovascular disease. By releasing neutrophil extracellular traps (NETs, neutrophils kill bacteria and exert pro-inflammatory and pro-thrombotic activities. Increased NETosis has been found in cross-sectional studies including treated type 2 diabetes mellitus (T2DM patients. In this study, we determined whether the ability of neutrophils to form NETs differs in diabetic patients pre- and post-hyperglycemic control versus healthy donors (HD, and the relationship between NETosis with pro-thrombotic, pro-inflammatory biomarkers and thrombotic clinical events.Diabetic patients recently diagnosed and after 6 and 12 months of treatment (N = 25 and HD (N = 25 were included. NET formation was studied by microscopy and fluorometry. Nucleosomes, HNE-DNA complexes, von Willebrand factor (vWF, IL6 and TNFα plasma levels were measured by ELISA and P-selectin on the platelet surface was assessed by cytometry.Basal levels of NETs in recently diagnosed T2DM patients were higher compared to HD. While TNFα stimulation of control neutrophils resulted in DNA release, patient neutrophils were not responsive. Although glycemia decreased after 6 months of metformin treatment, basal and TNFα and PMA-stimulated NETs reached normal values after 12 months. Compared to controls, nucleosomes, HNE-DNA complexes, IL-6 and TNFα levels were increased in recently diagnosed patients and decreased after 12 months of treatment. P-selectin and vWF levels were similar in both populations.Our data suggest that NETs could represent a biomarker for T2DM. Increased NETosis in T2DM patients does not appear to be the consequence of impaired glycemic control but rather due to pro-inflammatory cytokines and is not related to thrombotic events.

Platelet adhesion and plasma protein adsorption control of collagen surfaces by He+ ion implantation

International Nuclear Information System (INIS)

Kurotobi, K.; Suzuki, Y.; Nakajima, H.; Suzuki, H.; Iwaki, M.

2003-01-01

He + ion implanted collagen-coated tubes with a fluence of 1 x 10 14 ions/cm 2 were exhibited antithrombogenicity. To investigate the mechanisms of antithrombogenicity of these samples, plasma protein adsorption assay and platelet adhesion experiments were performed. The adsorption of fibrinogen (Fg) and von Willebrand factor (vWf) was minimum on the He + ion implanted collagen with a fluence of 1 x 10 14 ions/cm 2 . Platelet adhesion (using platelet rich plasma) was inhibited on the He + ion implanted collagen with a fluence of 1 x 10 14 ions/cm 2 and was accelerated on the untreated collagen and ion implanted collagen with fluences of 1 x 10 13 , 1 x 10 15 and 1 x 10 16 ions/cm 2 . Platelet activation with washed platelets was observed on untreated collagen and He + ion implanted collagen with a fluence of 1 x 10 14 ions/cm 2 and was inhibited with fluences of 1 x 10 13 , 1 x 10 15 and 1 x 10 16 ions/cm 2 . Generally, platelets can react with a specific ligand inside the collagen (GFOGER sequence). The results of platelets adhesion experiments using washed platelets indicated that there were no ligands such as GFOGER on the He + ion implanted collagen over a fluence of 1 x 10 13 ions/cm 2 . On the 1 x 10 14 ions/cm 2 implanted collagen, no platelet activation was observed due to the influence of plasma proteins. >From the above, it is concluded that the decrease of adsorbed Fg and vWf caused the antithrombogenicity of He + ion implanted collagen with a fluence of 1 x 10 14 ions/cm 2 and that plasma protein adsorption took an important role repairing the graft surface

Endothelial Injury Associated with Cold or Warm Blood Cardioplegia during Coronary Artery Bypass Graft Surgery

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Elmar W. Kuhn

2015-01-01

Full Text Available The aim of this investigation was to analyze the impact of intermittent cold blood cardioplegia (ICC and intermittent warm blood cardioplegia (IWC on endothelial injury in patients referred to elective on-pump coronary artery bypass graft (CABG surgery. Patients undergoing CABG procedures were randomized to either ICC or IWC. Myocardial injury was assessed by CK-MB and cardiac troponin T (cTnT. Endothelial injury was quantified by circulating endothelial cells (CECs, von Willebrand factor (vWF, and soluble thrombomodulin (sTM. Perioperative myocardial injury (PMI and major adverse cardiac events (MACE were recorded. Demographic data and preoperative risk profile of included patients (ICC: n=32, IWC: n=36 were comparable. No deaths, PMI, or MACE were observed. Levels of CK-MB and cTnT did not show intergroup differences. Concentrations of CECs peaked at 6 h postoperatively with significantly higher values for IWC-patients at 1 h (ICC: 10.1 ± 3.9/mL; IWC: 18.4 ± 4.1/mL; P=0.012 and 6 h (ICC: 19.3 ± 6.2/mL; IWC: 29.2 ± 6.7/mL; P<0.001. Concentrations of vWF (ICC: 178.4 ± 73.2 U/dL; IWC: 258.2 ± 89.7 U/dL; P<0.001 and sTM (ICC: 3.2 ± 2.1 ng/mL; IWC: 5.2 ± 2.4 ng/mL; P=0.011 were significantly elevated in IWC-group at 1 h postoperatively. This study shows that the use of IWC is associated with a higher extent of endothelial injury compared to ICC without differences in clinical endpoints.

Isolation and characterization of conditionally immortalized mouse glomerular endothelial cell lines.

Science.gov (United States)

Rops, Angelique L; van der Vlag, Johan; Jacobs, Cor W; Dijkman, Henry B; Lensen, Joost F; Wijnhoven, Tessa J; van den Heuvel, Lambert P; van Kuppevelt, Toin H; Berden, Jo H

2004-12-01

The culture and establishment of glomerular cell lines has proven to be an important tool for the understanding of glomerular cell functions in glomerular physiology and pathology. Especially, the recent establishment of a conditionally immortalized visceral epithelial cell line has greatly boosted the research on podocyte biology. Glomeruli were isolated from H-2Kb-tsA58 transgenic mice that contain a gene encoding a temperature-sensitive variant of the SV40 large tumor antigen, facilitating proliferative growth at 33 degrees C and differentiation at 37 degrees C. Glomerular endothelial cells were isolated from glomerular outgrowth by magnetic beads loaded with CD31, CD105, GSL I-B4, and ULEX. Clonal cell lines were characterized by immunofluorescence staining with antibodies/lectins specific for markers of endothelial cells, podocytes, and mesangial cells. Putative glomerular endothelial cell lines were analyzed for (1) cytokine-induced expression of adhesion molecules; (2) tube formation on Matrigel coating; and (3) the presence of fenestrae. As judged by immunostaining for Wilms tumor-1, smooth muscle actin (SMA), podocalyxin, and von Willebrand factor (vWF), we obtained putative endothelial, podocyte and mesangial cell lines. The mouse glomerular endothelial cell clone #1 (mGEnC-1) was positive for vWF, podocalyxin, CD31, CD105, VE-cadherin, GSL I-B4, and ULEX, internalized acetylated-low-density lipoprotein (LDL), and showed increased expression of adhesion molecules after activation with proinflammatory cytokines. Furthermore, mGEnC-1 formed tubes and contained nondiaphragmed fenestrae. The mGEnC-1 represents a conditionally immortalized cell line with various characteristics of differentiated glomerular endothelial cells when cultured at 37 degrees C. Most important, mGEnC-1 contains nondiaphragmed fenestrae, which is a unique feature of glomerular endothelial cells.

Desenvolvimento de uma ferramenta didática para o estudo da flexão composta oblíqua em seções quaisquer de concreto armado

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P. H. C. De Lyra

Full Text Available Tendo em vista a experiência de professores e pesquisadores do Brasil e do exterior no contexto da busca de novos e melhores métodos didáticos para ensino de Engenharia, constata-se que o uso de recursos multimídia interativa constitui uma abordagem promissora, com amplas possibilidades de aplicação em disciplinas de graduação. Nesse contexto, o presente trabalho trata do desenvolvimento de uma ferramenta multimídia de apoio ao ensino da flexão composta oblíqua no concreto armado, apresentando as suas funcionalidades, a estrutura do código e exemplos de aplicação. Para a construção da ferramenta, o applet “Verificação de seções quaisquer de concreto armado sob flexão composta oblíqua”, foi utilizada a linguagem de programação JavaTM e o ambiente de desenvolvimento NetBeans 5.5.1. O applet tratado neste artigo está disponível na Internet no endereço http://www.lmc.ep.usp.br/pesquisas/TecEdu/.

Cyclodextrin-Scaffolded Alamethicin with Remarkably Efficient Membrane Permeabilizing Properties and Membrane Current Conductance

DEFF Research Database (Denmark)

Hjørringgaard, Claudia Ulrich; Vad, Brian Stougaard; Matchkov, Vladimir

2012-01-01

Bacterial resistance to classical antibiotics is a serious medical problem, which continues to grow. Small antimicrobial peptides represent a potential solution and are increasingly being developed as novel therapeutic agents. Many of these peptides owe their antibacterial activity to the formati......-channel current measurements, the α-helices of the templated multimers were demonstrated to insert into lipid bilayers forming highly efficient and remarkably stable ion-channels...

Multimer Formation Explains Allelic Suppression of PRDM9 Recombination Hotspots.

Science.gov (United States)

Baker, Christopher L; Petkova, Pavlina; Walker, Michael; Flachs, Petr; Mihola, Ondrej; Trachtulec, Zdenek; Petkov, Petko M; Paigen, Kenneth

2015-09-01

Genetic recombination during meiosis functions to increase genetic diversity, promotes elimination of deleterious alleles, and helps assure proper segregation of chromatids. Mammalian recombination events are concentrated at specialized sites, termed hotspots, whose locations are determined by PRDM9, a zinc finger DNA-binding histone methyltransferase. Prdm9 is highly polymorphic with most alleles activating their own set of hotspots. In populations exhibiting high frequencies of heterozygosity, questions remain about the influences different alleles have in heterozygous individuals where the two variant forms of PRDM9 typically do not activate equivalent populations of hotspots. We now find that, in addition to activating its own hotspots, the presence of one Prdm9 allele can modify the activity of hotspots activated by the other allele. PRDM9 function is also dosage sensitive; Prdm9+/- heterozygous null mice have reduced numbers and less active hotspots and increased numbers of aberrant germ cells. In mice carrying two Prdm9 alleles, there is allelic competition; the stronger Prdm9 allele can partially or entirely suppress chromatin modification and recombination at hotspots of the weaker allele. In cell cultures, PRDM9 protein variants form functional heteromeric complexes which can bind hotspots sequences. When a heteromeric complex binds at a hotspot of one PRDM9 variant, the other PRDM9 variant, which would otherwise not bind, can still methylate hotspot nucleosomes. We propose that in heterozygous individuals the underlying molecular mechanism of allelic suppression results from formation of PRDM9 heteromers, where the DNA binding activity of one protein variant dominantly directs recombination initiation towards its own hotspots, effectively titrating down recombination by the other protein variant. In natural populations with many heterozygous individuals, allelic competition will influence the recombination landscape.

Idiopathic Non-Cirrhotic Intrahepatic Portal Hypertension (NCIPH)—Newer Insights into Pathogenesis and Emerging Newer Treatment Options

Science.gov (United States)

Goel, Ashish; Elias, Joshua E.; Eapen, Chundamannil E.; Ramakrishna, Banumathi; Elias, Elwyn

2014-01-01

Chronic microangiopathy of portal venules results in idiopathic non-cirrhotic intrahepatic portal hypertension (NCIPH). Recent data suggest a role for vasoactive factors of portal venous origin in the pathogenesis of this ‘pure’ vasculopathy of the liver. Enteropathies (often silent), are an important ‘driver’ of this disease. NCIPH is under-recognized and often mis-labeled as cryptogenic cirrhosis. Liver biopsy is needed to prove the diagnosis of NCIPH. In these patients, with advancing disease and increased porto-systemic shunting, the portal venous vasoactive factors bypass the liver filter and contribute to the development of pulmonary vascular endothelial disorders—porto-pulmonary hypertension and hepato-pulmonary syndrome as well as mesangiocapillary glomerulonephritis. Prognosis in NCIPH patients is determined by presence, recognition and management of associated disorders. With better understanding of the pathogenesis of NCIPH, newer treatment options are being explored. Imbalance in ADAMTS 13 (a disintegrin and metalloprotease with thrombospondin type 1 motif, member 13): vWF (von-Willebrand factor) ratio is documented in NCIPH patients and may have a pathogenic role. Therapeutic interventions to correct this imbalance may prove to be important in the management of NCIPH. PMID:25755567

The ability of multimerized cyclophilin A to restrict retrovirus infection

International Nuclear Information System (INIS)

Javanbakht, Hassan; Diaz-Griffero, Felipe; Yuan Wen; Yeung, Darwin F.; Li Xing; Song Byeongwoon; Sodroski, Joseph

2007-01-01

In owl monkeys, the typical retroviral restriction factor of primates, TRIM5α, is replaced by TRIMCyp. TRIMCyp consists of the TRIM5 RING, B-box 2 and coiled-coil domains, as well as the intervening linker regions, fused with cyclophilin A. TRIMCyp restricts infection of retroviruses, such as human immunodeficiency virus (HIV-1) and feline immunodeficiency virus (FIV), with capsids that can bind cyclophilin A. The TRIM5 coiled coil promotes the trimerization of TRIMCyp. Here we show that cyclophilin A that is oligomeric as a result of fusion with a heterologous multimer exhibits substantial antiretroviral activity. The addition of the TRIM5 RING, B-box 2 and Linker 2 to oligomeric cyclophilin A generated a protein with antiretroviral activity approaching that of wild-type TRIMCyp. Multimerization increased the binding of cyclophilin A to the HIV-1 capsid, promoting accelerated uncoating of the capsid and restriction of infection

PATHOGENESIS OF HEMORRHAGIC DUE TO DENGUE VIRUS

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Arief Suseno

2015-01-01

Full Text Available Dengue is a viral disease that is mediated by a mosquito, which causes morbidity and mortality. Viruses can increase vascular permeability which can lead to hemorrhagic diathesis or disseminated intravascular coagulation (DIC known as dengue hemorrhagic fever (DHF. In Indonesia, dengue hemorrhagic fever (DHF are caused by dengue virus infection which was found to be endemic accompanied by an explosion of extraordinary events that appear at various specified period. The diagnosis of dengue is determined based on the criteria of the World Health Organization (WHO, 1999, which are sudden high fever accompanied by a marked tendency to hemorrhage positive tourniquet test, petechiae, ecchymosis, purpura, mucosal hemorrhagic, hematemesis or melena and thrombocytopenia. The problem that still exists today is the mechanism of thrombocytopenia in patients with varying degrees of dengue involving levels of vWF (von Willebrand factor and prostaglandin I2 (PGI2 can not be explained. The mechanism of hemorrhagic in dengue virus infections acquired as a result of thrombocytopenia, platelet disfunction decreased coagulation factors, vasculopathy with endothelial injury and disseminated intravascular coagulation (DIC.

Process Parameters Optimization of 14nm MOSFET Using 2-D Analytical Modelling

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Noor Faizah Z.A.

2016-01-01

Full Text Available This paper presents the modeling and optimization of 14nm gate length CMOS transistor which is down-scaled from previous 32nm gate length. High-k metal gate material was used in this research utilizing Hafnium Dioxide (HfO2 as dielectric and Tungsten Silicide (WSi2 and Titanium Silicide (TiSi2 as a metal gate for NMOS and PMOS respectively. The devices are fabricated virtually using ATHENA module and characterized its performance evaluation via ATLAS module; both in Virtual Wafer Fabrication (VWF of Silvaco TCAD Tools. The devices were then optimized through a process parameters variability using L9 Taguchi Method. There were four process parameter with two noise factor of different values were used to analyze the factor effect. The results show that the optimal value for both transistors are well within ITRS 2013 prediction where VTH and IOFF are 0.236737V and 6.995705nA/um for NMOS device and 0.248635 V and 5.26nA/um for PMOS device respectively.

Diagnostic aspects of vibration-induced white finger.

Science.gov (United States)

Olsen, Niels

2002-01-01

Vibration-induced white finger (VWF) is a secondary type of Raynaud's phenomenon (RP) caused by exposure to hand-arm vibration. The present review concerns the cold-provoked attack of RP in vasospastic VWF. It concentrates on the most common clinical and laboratory methods used to diagnose RP in vibration-exposed subjects. Some physiological aspects of the attack of RP are mentioned to elucidate the diagnostic principles of the tests. Anamnestic diagnostics by medical interviews and questionnaires as well as cold-provocation tests with detection of finger colour, finger systolic blood pressure (FSP), recovery time of finger skin temperature and recovery time of normal nail colour after nail compression are mentioned. The discriminative capacity and the reproducibility of the tests are discussed. Cold-provocation tests with detection of finger colour or zero FSP during cooling are recommended to be used if an attack of RP has to be registered for diagnostic or medico-legal purposes in individual cases. An abnormal reduction in FSP during cooling makes a history of RP very probable and is a suitable laboratory test for groups of subjects. Both recovery tests may be useful screening tests in field studies of vibration-exposed subject groups.

Comparison of dosimetric characteristics of Siemens virtual and physical wedges for ONCOR linear accelerator

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Attalla Ehab

2010-01-01

Full Text Available Dosimetric properties of virtual wedge (VW and physical wedge (PW in 6- and 10-MV photon beams from a Siemens ONCOR linear accelerator, including wedge factors, depth doses, dose profiles, peripheral doses, are compared. While there is a great difference in absolute values of wedge factors, VW factors (VWFs and PW factors (PWFs have a similar trend as a function of field size. PWFs have stronger depth dependence than VWF due to beam hardening in PW fields. VW dose profiles in the wedge direction, in general, match very well with those of PW, except in the toe area of large wedge angles with large field sizes. Dose profiles in the nonwedge direction show a significant reduction in PW fields due to off-axis beam softening and oblique filtration. PW fields have significantly higher peripheral doses than open and VW fields. VW fields have similar surface doses as the open fields, while PW fields have lower surface doses. Surface doses for both VW and PW increase with field size and slightly with wedge angle. For VW fields with wedge angles 45° and less, the initial gap up to 3 cm is dosimetrically acceptable when compared to dose profiles of PW. VW fields in general use less monitor units than PW fields.

Acquired Von Willebrand’s Syndrome in Systemic Lupus Erythematosus

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Sara Taveras Alam

2014-01-01

Full Text Available Acquired von Willebrand syndrome (AVWS is an uncommon, underdiagnosed, and heterogeneous disease which is increasingly recognized as a cause of bleeding diatheses. Systemic lupus erythematosus (SLE is an infrequent cause of AVWS. Herein, we report a case of AVWS diagnosed during the initial presentation of SLE in a previously healthy young man with no family history of bleeding diathesis who presented with worsening epistaxis, gastrointestinal bleeding, and anasarca. He was found to have severe anemia and prolonged activated partial thromboplastin time (aPTT with severely decreased levels of von Willebrand factor (VWF measurements in addition to markedly decreased factor VIII levels. Further evaluation revealed nephrotic syndrome and interstitial lung disease due to SLE. He initially received combination therapy with intravenous immunoglobulin (IVIG and von Willebrand factor/factor VIII concentrates without significant improvement. Treatment with steroids, cyclophosphamide, and rituximab was followed by clinical improvement evidenced by cessation of bleeding. The short follow-up did not allow us to definitely prove the therapeutic effect of immunosuppressive treatment on AVWS in SLE patients. This case adds to the literature supporting the relationship between AVWS and SLE and highlights the importance of combination therapy in the treatment of severe AVWS as well as the role of IVIG, cyclophosphamide, and rituximab in AVWS associated with SLE.

Genotypic and Phenotypic Characterization of Enterotoxigenic Escherichia coli Strains Isolated from Peruvian Children

Science.gov (United States)

2010-09-01

adhesion, ETEC elabo- rates one or both of two enterotoxins: heat-labile toxin (LT), a protein multimer which shares many features with cholera toxin...pathogens (Shigella, Salmonella. Vibrio , Campylo/Jacter, Gi- ardia Iamblia, Cryptosporidium, and rotavirus) by conventional methods. Five lactose...studies performed in developing coun- tries: 38% in children ɚ years of age in Nicaragua (19), 33% in children ə year of age in Mexico (6), and 18% in

un_focus - Les femmes et la terre : Des droits fonciers pour une ...

International Development Research Centre (IDRC) Digital Library (Canada)

1 janv. 2011 ... Étonnamment, il existe peu d'informations détaillées sur le rapport des femmes à la terre, et encore moins de données provenant des femmes elles-mêmes. Le présent livre, qui s'inspire des travaux de recherche financés par le CRDI au fil des ans, vise à combler ce vide. Multimédia : Une playlist YouTube.

Demand for Multimedia in the Classroom

OpenAIRE

Boyer, Tracy A.; Briggeman, Brian C.; Norwood, F. Bailey

2009-01-01

This study elicits preferences for multimedia in the classroom for students and faculty members in agricultural economics. Employing an Internet-based conjoint ranking survey, the results show that students prefer multimedia instructional tools over a traditional chalkboard/whiteboard lecture format while faculty members do not. Neither students nor faculty members are enthusiastic about electronic textbooks, and students will accept them only if they save $80. Finally, preferences for multim...

Multimedia and security: Workshop at ACM Multimedia '98, Bristol, U.K., September 12 - 13, 1998

OpenAIRE

Dittmann, J.; Wohlmacher, P.; Horster, P.; Steinmetz, R.

1998-01-01

In this paper we describe the most important security requirements, which must be fulfilled by today's IT-systems, and the security measures used to satisfy these requirements. These security measures are based on modern cryptographic mechanisms as well as on security infrastructures. Regarding data security and communication security in particular in the field of multimedia, the requirements on security increase. If and in which way the discussed security mechanisms can be applied to multime...

Synthesis of Cu Nanoparticles Using Copper Carbonate as Cu Source Toward Versatile Applications.

Science.gov (United States)

Yano, Kazuhisa; Ishizaki, Toshitaka; Sugiyama, Hidehiko

2018-07-01

Cu nanoparticles (NPs) coated with polyvinylpyrrolidone (PVP) were fabricated by polyol method using copper carbonate as a raw material. To increase the reaction temperature, glycol multimers such as diethylene glycol, triethylene glycol, or tetraethylene glycol were examined as a solvent. With increasing degree of multimerization, average diameter of Cu NPs decreased. The synthesis of Cu NPs was further investigated by changing reaction temperature, the amount and molecular weight of PVP in triethylene glycol as a solvent. Average diameter and standard deviation of Cu NPs were found to be highly dependent on those factors. As a result, fine Cu NPs ranging from 28 to 67 nm in average size with narrow size distribution (standard deviation: 16-28%) were obtained. The obtained Cu NPs were applied to a nanofluid, which showed higher thermal conductivity than the theoretical value. The antibacterial activity of Cu NPs was also demonstrated, and found to have strong antibacterial activity.

Hemostasis in Overt and Subclinical Hyperthyroidism

Science.gov (United States)

Ordookhani, Arash; Burman, Kenneth D.

2017-01-01

Context There are contradictory results on the effect of hyperthyroidism on hemostasis. Inadequate population-based studies limited their clinical implications, mainly on the risk of venous thromboembolism (VTE). The present review focuses on hemostatic changes in overt and subclinical hyperthyroidism. Methods A systematic literature search was conducted employing MEDLINE database. The following words were used for the search: Hyperthyroidism; thyrotoxicosis; Graves disease; goiter, nodular; hemostasis; blood coagulation factors; blood coagulation disorders; venous thromboembolism; bleeding; fibrinolysis. The articles that were related to hyperthyroidism and hemostasis are used in this manuscript. Results Hyperthyroidism, either overt or subclinical, renders a hypercoagulable state, although there are several studies with contradictory findings in the literature. Hypercoagulability may be caused by an increase in the level of various coagulation factors such as factor (F) VIII, FX, FIX, von Willebrand F (vWF), and fibrinogen, while hypofibrinolysis by changes in coagulation parameters such as a decrease in plasmin and plasmin activator or an increase in α2-antiplasmin, plasminogen activator inhibitor-1 and thrombin activatable fibrinolysis inhibitor Conclusions Although many reports are in favor of a hypercoagulable state in overt hyperthyroidism but this finding at the biochemical level and its clinical implication, on the occurrence of VTE, has yet to be confirmed. PMID:29201071

Carvacrol promotes angiogenic paracrine potential and endothelial differentiation of human mesenchymal stem cells at low concentrations.

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Matluobi, Danial; Araghi, Atefeh; Maragheh, Behnaz Faramarzian Azimi; Rezabakhsh, Aysa; Soltani, Sina; Khaksar, Majid; Siavashi, Vahid; Feyzi, Adel; Bagheri, Hesam Saghaei; Rahbarghazi, Reza; Montazersaheb, Soheila

2018-01-01

Phenolic monoterpene compound, named Carvacrol, has been found to exert different biological outcomes. It has been accepted that the angiogenic activity of human mesenchymal stem cells was crucial in the pursuit of appropriate regeneration. In the current experiment, we investigated the contribution of Carvacrol on the angiogenic behavior of primary human mesenchymal stem cells. Mesenchymal stem cells were exposed to Carvacrol in a dose ranging from 25 to 200μM for 48h. We measured cell survival rate by MTT assay and migration rate by a scratch test. The oxidative status was monitored by measuring SOD, GPx activity. The endothelial differentiation was studied by evaluating the level of VE-cadherin and vWF by real-time PCR and ELISA analyses. The content of VEGF and tubulogenesis behavior was monitored in vitro. We also conducted Matrigel plug in vivo CAM assay to assess the angiogenic potential of conditioned media from human mesenchymal stem cells after exposure to Carvacrol. Carvacrol was able to increase mesenchymal stem cell survival and migration rate (pcells by detecting vWF and VE-cadherin expression (pmesenchymal stem cells conditioned media improved angiogenesis tube formation in vitro (pmesenchymal stem cells by modulating cell differentiation and paracrine angiogenic response. Copyright © 2017 Elsevier Inc. All rights reserved.

Tumor and Endothelial Cell Hybrids Participate in Glioblastoma Vasculature

Directory of Open Access Journals (Sweden)

Soufiane El Hallani

2014-01-01

Full Text Available Background. Recently antiangiogenic therapy with bevacizumab has shown a high but transient efficacy in glioblastoma (GBM. Indeed, GBM is one of the most angiogenic human tumors and endothelial proliferation is a hallmark of the disease. We therefore hypothesized that tumor cells may participate in endothelial proliferation of GBM. Materials and Methods. We used EGFR FISH Probe to detect EGFR amplification and anti-CD31, CD105, VE-cadherin, and vWF to identify endothelial cells. Endothelial and GBM cells were grown separately, labeled with GFP and DsRed lentiviruses, and then cocultured with or without contact. Results. In a subset of GBM tissues, we found that several tumor endothelial cells carry EGFR amplification, characteristic of GBM tumor cells. This observation was reproduced in vitro: when tumor stem cells derived from GBM were grown in the presence of human endothelial cells, a fraction of them acquired endothelial markers (CD31, CD105, VE-cadherin, and vWF. By transduction with GFP and DsRed expressing lentiviral vectors, we demonstrate that this phenomenon is due to cell fusion and not transdifferentiation. Conclusion. A fraction of GBM stem cells thus has the capacity to fuse with endothelial cells and the resulting hybrids may participate in tumor microvascular proliferation and in treatment resistance.

Biosynthesis and characterization of a non-repetitive polypeptide derived from silk fibroin heavy chain

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Yang, Gaoqiang; Wu, Mingyang; Yi, Honggen; Wang, Jiannan, E-mail: wangjn@suda.edu.cn

2016-02-01

Silk fibroin heavy chain is the major protein component of Bombyx mori silk fibroin and is composed of 12 repetitive and 11 non-repetitive regions, with the non-repetitive domain consisting of a hydrophilic polypeptide chain. In order to determine the biomedical function of the non-repetitive domain or potentially use it to modify hydrophobic biomaterials, high-purity isolation is necessary. Previously, we cloned and extended a gene motif (f(1)) encoding the non-repetitive domain. Here, this motif and its multimers are inserted into a glutathione S-transferase (GST)-tagged fusion-protein expression vector. Motif f(1) and multimers f(4) and f(8) were expressed in Escherichia coli BL21 cells following isopropyl β-D-1-thiogalactopyranoside induction, purified by GST-affinity chromatography, and single bands of purified fusion proteins GST-F(1), GST-F(4), and GST-F(8), were visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Target polypeptides F(1), F(4), and F(8), were cleaved clearly from the GST-fusion tag following thrombin digestion. Mass spectrometry results indicate that the molecular weights associated with fusion proteins GST-F(1), GST-F(4), and GST-F(8) are 31.5, 43.8, and 59.0 kDa, respectively, and with the cleaved polypeptides F(1), F(4), and F(8) are 4.8, 16.8, and 32.8 kDa, respectively. The F(1), F(4), and F(8) polypeptide chains are negatively charged with isoelectric points (pI) of 3.3, 3.2, and 3.0, respectively. The molecular weight and pI values of the polypeptide chains are consistent with the predicted values and the amino acid compositions similar to predicted sequences. FTIR and CD results show the molecular conformation of F(1) was mainly random coil, and more stable α-helix structure formed in longer molecular chain. - Highlights: • A non-repetitive domain and its multimers of silk fibroin were expressed by E. coli. • The corresponding target polypeptides F(1), F(4) and F(8) were cleaved clearly. • Their

Acquired thrombotic thrombocytopenic purpura: new therapeutic options and their optimal use.

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Cataland, S R; Wu, H M

2015-06-01

Advances in our understanding of the pathophysiology of both congenital and acquired thrombotic thrombocytopenic purpura (TTP) have led to both an increased understanding of the disease and novel approaches to therapy. The efficacy of rituximab in acquired TTP has led to consideration of rituximab as a prophylactic therapy to prevent relapse of TTP. Novel therapies that target the A1 domain of von Willebrand factor (VWF) to block the formation of microthrombotic disease have also entered clinical study and have demonstrated promise as potential therapeutic options. Additionally, a recombinant ADAMTS13 protease has been developed which may be an important therapeutic option for both congenital and acquired TTP. The development of these new therapeutic options for patients diagnosed with TTP has increased the importance of conducting prospective, randomized studies with these agents to both confirm their efficacy and more importantly understand their most appropriate role in the treatment of patients with TTP. © 2015 International Society on Thrombosis and Haemostasis.

Mouse podoplanin supports adhesion and aggregation of platelets under arterial shear: A novel mechanism of haemostasis.

Science.gov (United States)

Lombard, Stephanie E; Pollitt, Alice Y; Hughes, Craig E; Di, Ying; Mckinnon, Tom; O'callaghan, Chris A; Watson, Steve P

2017-11-01

The podoplanin-CLEC-2 axis is critical in mice for prevention of hemorrhage in the cerebral vasculature during mid-gestation. This raises the question as to how platelets are captured by podoplanin on neuroepithelial cells in a high shear environment. In this study, we demonstrate that mouse platelets form stable aggregates on mouse podoplanin at arterial shear through a CLEC-2 and Src kinase-dependent pathway. Adhesion and aggregation are also dependent on the platelet glycoprotein (GP) receptors, integrin αIIbβ3 and GPIb, and the feedback agonists ADP and thromboxane A 2 (TxA 2 ). CLEC-2 does not bind to von Willebrand factor (VWF) suggesting that the interaction with podoplanin is sufficient to both tether and activate platelets. Consistent with this, the surface plasmon resonance measurements reveal that mouse CLEC-2 binds to mouse podoplanin with nanomolar affinity. The present findings demonstrate a novel pathway of hemostasis in which podoplanin supports platelet capture and activation at arteriolar rates of shear.

mutabilidade e persistência num exercício de animação

OpenAIRE

Gonçalves, Marina Alexandra Almeida e Silva, 1986-

2012-01-01

Tese de mestrado, Arte e multimédia, Audiovisuais, Universidade de Lisboa, Faculdade de Belas Artes, 2012 Memory is a subject that allows multiple interpretations. The choice of a sub-theme is necessary in order to specify the study object. There are some art pieces that are based on the problematic of illnesses associated with memory; others that explore the processes and techniques of memorization; while others exploit the link between memory and traumatic experiences; and some that are...

memória de uma viagem à memória

OpenAIRE

Figueiredo, Maria Rosa Dionisio, 1988-

2012-01-01

Tese de mestrado, Arte e Multiméia - Audiovisuais, Universidade de Lisboa, Faculdade de Belas Artes, 2012 This work concludes a proof in a Master degree on Multimedia Art in the audio visual field. The idea of memory, with the possibility of its immateriality and dissolution, and reminiscence are the subject matter of this project. Human memory, to which attention is devoted here for its decisive importance to the gathering of knowledge, is the ability to store information. Immateria...

Human-computer interaction : Guidelines for web animation

OpenAIRE

Galyani Moghaddam, Golnessa; Moballeghi, Mostafa

2006-01-01

Human-computer interaction in the large is an interdisciplinary area which attracts researchers, educators, and practioners from many differenf fields. Human-computer interaction studies a human and a machine in communication, it draws from supporting knowledge on both the machine and the human side. This paper is related to the human side of human-computer interaction and focuses on animations. The growing use of animation in Web pages testifies to the increasing ease with which such multim...

Novel multiple opioid ligands based on 4-aminobenzazepinone (Aba), azepinoindole (Aia) and tetrahydroisoquinoline (Tic) scaffolds

Science.gov (United States)

Ballet, Steven; Marczak, Ewa D.; Feytens, Debby; Salvadori, Severo; Sasaki, Yusuke; Abell, Andrew D.; Lazarus, Lawrence H.; Balboni, Gianfranco; Tourwé, Dirk

2010-01-01

The dimerization and trimerization of the Dmt-Tic, Dmt-Aia and Dmt-Aba pharmacophores provided multiple ligands which were evaluated in vitro for opioid receptor binding and functional activity. Whereas the Tic- and Aba multimers proved to be dual and balanced δ/μ antagonists, as determined by the functional [S35]GTPγS binding assay, the dimerization of potent Aia-based ‘parent’ ligands unexpectedly resulted in substantial less efficient receptor binding and non-active dimeric compounds. PMID:20137938

[Effect of medicines for activating blood and reinforcing Qi on angiogenesis in infarcted myocardium edge area of acute myocardial infarction model in rats].

Science.gov (United States)

Zang, Wen-Hua; Yin, Shen-Hua; Tang, De-Cai; Li, Bing-Bing

2014-03-01

To study the effect of medicines for activating blood and reinforcing Qi on the number of new micro-vessels and the protein expressions of VEGF and bFGF in the infarcted myocardium edge area of acute myocardial infarction (AMI) model in rats. The AMI model of rats was established. After the successful model establishment, rats were randomly divided into the sham-operated group, the model group, the Danshen-Huangqi (1 : 2) group, the Danshen-Huangqi (1 : 1) group, the Chuanxiong-Huangqi (1 : 2) group, the Danshen group, the Chuanxiong group, the Chishao group and the Shexiang Baoxin pill group, with five rats in each group. Rats in each medicated group were orally administered with drugs as per 13.5 g x kg(-1) x d(-1) once everyday for three weeks. The immunohistochemical SP method was adopted to detect the expression of vWF in myocardial tissues, and count the number of micro-vessels (MVC). The protein expression of VEGF and bFGF in myocardial tissues were determined by Western blot. The new micro-vessels stained by vWF factor could be found in the infarcted myocardium edge area of the sham-operated group, the model group and all of medicated groups. The sham-operated group show unobvious new micro-vessels in myocardial tissues. A small amount of new micro-vessels could be seen in the infarcted myocardium edge area of the model group. Whereas a larger number of micro-vessels could be seen in the infarcted myocardium edge area of all of medicated groups. The differences between the sham-operated group and the model group had statistical significance (P effect in promoting angiogenesis. Their mechanism for promoting angiogenesis may be related to the improvement of the protein expressions of VEGF and bFGF, so as to increase the contents of VEGF and bFGF and promote the angiogenesis of new vessels.

Le rôle du médecin anesthésiste-réanimateur dans la prise en ...

African Journals Online (AJOL)

La maladie de Von Willebrand (VWD) est la maladie hémorragique constitutionnelle de l'hémostase la plus fréquente. Elle est liée à un déficit, soit quantitatif, soit qualitatif en facteur willebrand (VWF). Elle se caractérise par son extrême hétérogénéité sur les plans clinique, phénotypique et génotypique. La grossesse et ...

Protein mobilities and P-selectin storage in Weibel–Palade bodies

OpenAIRE

Kiskin, Nikolai I.; Hellen, Nicola; Babich, Victor; Hewlett, Lindsay; Knipe, Laura; Hannah, Matthew J.; Carter, Tom

2010-01-01

Using fluorescence recovery after photobleaching (FRAP) we measured the mobilities of EGFP-tagged soluble secretory proteins in the endoplasmic reticulum (ER) and in individual Weibel–Palade bodies (WPBs) at early (immature) and late (mature) stages in their biogenesis. Membrane proteins (P-selectin, CD63, Rab27a) were also studied in individual WPBs. In the ER, soluble secretory proteins were mobile; however, following insertion into immature WPBs larger molecules (VWF, Proregion, tPA) and P...

Angiogenesis in mucous retention cyst: a human in vivo-like model of endothelial cell differentiation in mucous substrate.

Science.gov (United States)

Swelam, Wael; Ida-Yonemochi, Hiroko; Saku, Takashi

2005-01-01

Mucous retention cysts contain a mucous pool in the lumina, in which pure angiogenic processes are occasionally observed. By using this unique human material, our aim was to understand the in vivo angiogenic process. Fifteen surgical tissue samples of mucous retention cysts of the lip were examined for expression of vascular endothelial markers and extracellular matrix molecules by immunohistochemistry and in situ hybridization (ISH). Endothelial cells forming new vascular channels showed immunopositivities for CD31, CD34, vascular endothelial growth factor (VEGF), and von Willebrand factor (vWF). These newly formed capillaries were surrounded by tenascin-positive matrices and further by a dense infiltration of CD68-positive cells with foamy to epitheloid appearances. Some of these cells were simultaneously positive for CD34, VEGF, and one of its receptors, Flk-1, and they showed definite mRNA as well as protein signals for tenascin. In addition, these cells often tended to be aligned, which suggested tubule formation. The results suggest that monocyte/macrophage lineage cells are a major source for endothelial cells at least in mucous retention cysts and that tenascin produced by those cells plays an important role in differentiation of endothelial cells.

Role of altered coagulation-fibrinolytic system in the pathophysiology of diabetic retinopathy.

Science.gov (United States)

Behl, Tapan; Velpandian, Thirumurthy; Kotwani, Anita

2017-05-01

The implications of altered coagulation-fibrinolytic system in the pathophysiology of several vascular disorders, such as stroke and myocardial infarction, have been well researched upon and established. However, its role in the progression of diabetic retinopathy has not been explored much. Since a decade, it is known that hyperglycemia is associated with a hypercoagulated state and the various impairments it causes are well acknowledged as independent risk factors for the development of cardiovascular diseases. But recent studies suggest that the hypercoagulative state and diminished fibrinolytic responses might also alter retinal homeostasis and induce several deleterious molecular changes in retinal cells which aggravate the already existing hyperglycemia-induced pathological conditions and thereby lead to the progression of diabetic retinopathy. The major mediators of coagulation-fibrinolytic system whose concentration or activity get altered during hyperglycemia include fibrinogen, antithrombin-III (AT-III), plasminogen activator inhibitor-1 (PAI-1) and von Willebrand factor (vWF). Inhibiting the pathways by which these altered mediators get involved in the pathophysiology of diabetic retinopathy can serve as potential targets for the development of an adjuvant novel alternative therapy for diabetic retinopathy. Copyright © 2017 Elsevier Inc. All rights reserved.

Constitutive dimerization of the G-protein coupled receptor, neurotensin receptor 1, reconstituted into phospholipid bilayers.

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Harding, Peter J; Attrill, Helen; Boehringer, Jonas; Ross, Simon; Wadhams, George H; Smith, Eleanor; Armitage, Judith P; Watts, Anthony

2009-02-01

Neurotensin receptor 1 (NTS1), a Family A G-protein coupled receptor (GPCR), was expressed in Escherichia coli as a fusion with the fluorescent proteins eCFP or eYFP. A fluorophore-tagged receptor was used to study the multimerization of NTS1 in detergent solution and in brain polar lipid bilayers, using fluorescence resonance energy transfer (FRET). A detergent-solubilized receptor was unable to form FRET-competent complexes at concentrations of up to 200 nM, suggesting that the receptor is monomeric in this environment. When reconstituted into a model membrane system at low receptor density, the observed FRET was independent of agonist binding, suggesting constitutive multimer formation. In competition studies, decreased FRET in the presence of untagged NTS1 excludes the possibility of fluorescent protein-induced interactions. A simulation of the experimental data indicates that NTS1 exists predominantly as a homodimer, rather than as higher-order multimers. These observations suggest that, in common with several other Family A GPCRs, NTS1 forms a constitutive dimer in lipid bilayers, stabilized through receptor-receptor interactions in the absence of other cellular signaling components. Therefore, this work demonstrates that well-characterized model membrane systems are useful tools for the study of GPCR multimerization, allowing fine control over system composition and complexity, provided that rigorous control experiments are performed.

Trench Foot or Non-Freezing Cold Injury As a Painful Vaso-Neuropathy: Clinical and Skin Biopsy Assessments

Directory of Open Access Journals (Sweden)

Praveen Anand

2017-09-01

Full Text Available BackgroundTrench foot, or non-freezing cold injury (NFCI, results from cold exposure of sufficient severity and duration above freezing point, with consequent sensory and vascular abnormalities which may persist for years. Based on observations of Trench foot in World War II, the condition was described as a vaso-neuropathy. While some reports have documented nerve damage after extreme cold exposure, sensory nerve fibres and vasculature have not been assessed with recent techniques in NFCI.ObjectiveTo assess patients with chronic sensory symptoms following cold exposure, in order to diagnose any underlying small fibre neuropathy, and provide insight into mechanisms of the persistent pain and cold hypersensitivity.MethodsThirty soldiers with cold exposure and persistent sensory symptoms (>4 months were assessed with quantitative sensory testing, nerve conduction studies, and skin biopsies. Immunohistochemistry was used to assess intraepidermal (IENF and subepidermal (SENF nerve fibres with a range of markers, including the pan-neuronal marker protein gene product 9.5 (PGP 9.5, regenerating fibres with growth-associated protein 43 (GAP43, and nociceptor fibres with transient receptor potential cation channel subfamily V member 1 (TRPV1, sensory neuron-specific receptor (SNSR, and calcitonin gene-related peptide (CGRP. von Willebrand factor (vWF, endothelial nitric oxide synthase (eNOS, and vascular endothelial growth factor (VEGF were used for assessing blood vessels, and transient receptor potential cation channel, subfamily A member 1 (TRPA1 and P2X purinoceptor 7 (P2X7 for keratinocytes, which regulate nociceptors via release of nerve growth factor.ResultsClinical examination showed pinprick sensation was abnormal in the feet of 20 patients (67%, and between 67 and 83% had abnormalities of thermal thresholds to the different modalities. 7 patients (23% showed reduced sensory action potential amplitude of plantar nerves. 27 patients (90% had

Hepatitis C virus core protein induces dysfunction of liver sinusoidal endothelial cell by down-regulation of silent information regulator 1.

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Sun, Li-Jie; Yu, Jian-Wu; Shi, Yu-Guang; Zhang, Xiao-Yu; Shu, Meng-Ni; Chen, Mo-Yang

2018-05-01

Hepatic fibrosis is a frequent feature of chronic hepatitis C virus (HCV) infection. Some evidence has suggested the potential role of silent information regulator 1 (SIRT1) in organ fibrosis. The aim of this study was to investigate the effect of HCV core protein on expression of SIRT1 of liver sinusoidal endothelial cell (LSEC) and function of LSEC. LSECs were co-cultured with HepG2 cells or HepG2 cells expressing HCV core protein and LSECs cultured alone were used as controls. After co-culture, the activity and expression levels of mRNA and protein of SIRT1 in LSEC were detected by a SIRT1 fluorometric assay kit, real time-PCR (RT-PCR), Western blot, respectively. The levels of adiponectin receptor 2 (AdipoR2), endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor (VEGF) were measured by Western blot. Cluster of differentiation 31 (CD31), CD14, and von Willebrand factor (vWf) of LSECs was performed by flow cytometry. The level of reactive oxygen species (ROS) was assayed. Malondialdehyde (MDA), superoxide dismutase (SOD), adiponectin, nitric oxide (NO), and endothelin-1 (ET-1) levels in the co-culture supernatant were measured. The co-culture supernatant was then used to cultivate LX-2 cells. The levels of α-smooth muscle actin (ASMA) and transforming growth factor-β1 (TGF-β1) protein in LX-2 cells were measured by Western blot. Compared with LSEC co-cultured with HepG2 cells group, in LSEC co-cultured with HepG2-core cells group, the activity and expression level of mRNA and protein of SIRT1 reduced; the level of adiponectin reduced and the expression level of AdipoR2 protein decreased; ROS levels increased; the expression level of eNOS, VEGF protein decreased; and the expression level of CD14 decreased; the expression level of vWf and CD31 increased; NO and SOD levels decreased; whereas ET-1 and MDA levels increased; the levels of ASMA and TGF-β1 protein in LX-2 cells increased. SIRT1 activator improved the above-mentioned changes

Analysis of cellular and humoral immune responses against cytomegalovirus in patients with autoimmune Addison's disease.

Science.gov (United States)

Edvardsen, Kine; Hellesen, Alexander; Husebye, Eystein S; Bratland, Eirik

2016-03-09

Autoimmune Addison's disease (AAD) is caused by multiple genetic and environmental factors. Variants of genes encoding immunologically important proteins such as the HLA molecules are strongly associated with AAD, but any environmental risk factors have yet to be defined. We hypothesized that primary or reactivating infections with cytomegalovirus (CMV) could represent an environmental risk factor in AAD, and that CMV specific CD8(+) T cell responses may be dysregulated, possibly leading to a suboptimal control of CMV. In particular, the objective was to assess the HLA-B8 restricted CD8(+) T cell response to CMV since this HLA class I variant is a genetic risk factor for AAD. To examine the CD8(+) T cell response in detail, we analyzed the HLA-A2 and HLA-B8 restricted responses in AAD patients and healthy controls seropositive for CMV antibodies using HLA multimer technology, IFN-γ ELISpot and a CD107a based degranulation assay. No differences between patients and controls were found in functions or frequencies of CMV-specific T cells, regardless if the analyses were performed ex vivo or after in vitro stimulation and expansion. However, individual patients showed signs of reactivating CMV infection correlating with poor CD8(+) T cell responses to the virus, and a concomitant upregulation of interferon regulated genes in peripheral blood cells. Several recently diagnosed AAD patients also showed serological signs of ongoing primary CMV infection. CMV infection does not appear to be a major environmental risk factor in AAD, but may represent a precipitating factor in individual patients.

Association of air pollution sources and aldehydes with biomarkers of blood coagulation, pulmonary inflammation, and systemic oxidative stress.

Science.gov (United States)

Altemose, Brent; Robson, Mark G; Kipen, Howard M; Ohman Strickland, Pamela; Meng, Qingyu; Gong, Jicheng; Huang, Wei; Wang, Guangfa; Rich, David Q; Zhu, Tong; Zhang, Junfeng

2017-05-01

Using data collected before, during, and after the 2008 Summer Olympic Games in Beijing, this study examines associations between biomarkers of blood coagulation (vWF, sCD62P and sCD40L), pulmonary inflammation (EBC pH, EBC nitrite, and eNO), and systemic oxidative stress (urinary 8-OHdG) with sources of air pollution identified utilizing principal component analysis and with concentrations of three aldehydes of health concern. Associations between the biomarkers and the air pollution source types and aldehydes were examined using a linear mixed effects model, regressing through seven lag days and controlling for ambient temperature, relative humidity, gender, and day of week for the biomarker measurements. The biomarkers for pulmonary inflammation, particularly EBC pH and eNO, were most consistently associated with vehicle and industrial combustion, oil combustion, and vegetative burning. The biomarkers for blood coagulation, particularly vWF and sCD62p, were most consistently associated with oil combustion. Systemic oxidative stress biomarker (8-OHdG) was most consistently associated with vehicle and industrial combustion. The associations of the biomarkers were generally not significant or consistent with secondary formation of pollutants and with the aldehydes. The findings support policies to control anthropogenic pollution sources rather than natural soil or road dust from a cardio-respiratory health standpoint.

Life-threatening subdural hematoma after aortic valve replacement in a patient with Heyde syndrome: a case report.

Science.gov (United States)

Uchida, Tetsuro; Hamasaki, Azumi; Ohba, Eiichi; Yamashita, Atsushi; Hayashi, Jun; Sadahiro, Mitsuaki

2017-08-08

Heyde syndrome is known as a triad of calcific aortic stenosis, anemia due to gastrointestinal bleeding from angiodysplasia, and acquired type 2A von Willebrand disease. This acquired hemorrhagic disorder is characterized by the loss of the large von Willebrand factor multimers due to the shear stress across the diseased aortic valve. The most frequently observed type of bleeding in these patients is mucosal or skin bleeding, such as epistaxis, followed by gastrointestinal bleeding. On the other hand, intracranial hemorrhage complicating Heyde syndrome is extremely rare. A 77-year-old woman presented to our hospital with severe aortic stenosis and severe anemia due to gastrointestinal bleeding and was diagnosed with Heyde syndrome. Although aortic valve replacement was performed without recurrent gastrointestinal bleeding, postoperative life-threatening acute subdural hematoma occurred with a marked midline shift. Despite prompt surgical evacuation of the hematoma, she did not recover consciousness and she died 1 month after the operation. Postoperative subdural hematoma is rare, but it should be kept in mind as a devastating hemorrhagic complication, especially in patients with Heyde syndrome.

Complexity in Acid?Base Titrations: Multimer Formation Between Phosphoric Acids and Imines

OpenAIRE

Malm, Christian; Kim, Heejae; Wagner, Manfred; Hunger, Johannes

2017-01-01

Abstract Solutions of Br?nsted acids with bases in aprotic solvents are not only common model systems to study the fundamentals of proton transfer pathways but are also highly relevant to Br?nsted acid catalysis. Despite their importance the light nature of the proton makes characterization of acid?base aggregates challenging. Here, we track such acid?base interactions over a broad range of relative compositions between diphenyl phosphoric acid and the base quinaldine in dichloromethane, by u...

Extrachromosomal circles of satellite repeats and 5S ribosomal DNA in human cells

Directory of Open Access Journals (Sweden)

Cohen Sarit

2010-03-01

Full Text Available Abstract Background Extrachomosomal circular DNA (eccDNA is ubiquitous in eukaryotic organisms and was detected in every organism tested, including in humans. A two-dimensional gel electrophoresis facilitates the detection of eccDNA in preparations of genomic DNA. Using this technique we have previously demonstrated that most of eccDNA consists of exact multiples of chromosomal tandemly repeated DNA, including both coding genes and satellite DNA. Results Here we report the occurrence of eccDNA in every tested human cell line. It has heterogeneous mass ranging from less than 2 kb to over 20 kb. We describe eccDNA homologous to human alpha satellite and the SstI mega satellite. Moreover, we show, for the first time, circular multimers of the human 5S ribosomal DNA (rDNA, similar to previous findings in Drosophila and plants. We further demonstrate structures that correspond to intermediates of rolling circle replication, which emerge from the circular multimers of 5S rDNA and SstI satellite. Conclusions These findings, and previous reports, support the general notion that every chromosomal tandem repeat is prone to generate eccDNA in eukryoric organisms including humans. They suggest the possible involvement of eccDNA in the length variability observed in arrays of tandem repeats. The implications of eccDNA on genome biology may include mechanisms of centromere evolution, concerted evolution and homogenization of tandem repeats and genomic plasticity.

Adenovirus chromatin structure at different stages of infection

Energy Technology Data Exchange (ETDEWEB)

Daniell, E.; Groff, D.E.; Fedor, M.J.

1981-12-01

The authors investigated the structure of adenovirus deoxyribonecleic acid (DNA)-protein complexes in nuclei of infected cells by using micrococal nuclease. Parental (infecting) DNA was digested into multimers which had a unit fragment size that was indistinguishable from the size of the nucleosomal repeat of cellular chromatin. This pattern was maintained in parental DNA throughout infection. Similar repeating units were detected in hamster cells that were nonpermissive for human adenovirus and in cells pretreated with n-butyrate. Late in infection, the pattern of digestion of viral DNA was determined by two different experimental approaches. Nuclear DNA was electrophoresed, blotted, and hybridized with labeled viral sequences; in this procedure all virus-specific DNA was detected. This technique revealed a diffuse protected band of viral DNA that was smaller than 160 base pairs, but no discrete multimers. All regions of the genome were represented in the protected DNA. To examine the nuclease protection of newly replicated viral DNA, infected cells were labeled with (/sup 3/)thymidine after blocking of cellular DNA synthesis but not viral DNA synthesis. With this procedure they identified a repeating unit which was distinctly different from the cellular nucleosomal repeat. The authors found broad bands with midpoints at 200, 400, and 600 base pairs, as well as the limit digest material revealed by blotting. High-resolution acrylamide gel electrophoresis revealed that the viral species comprised a series of closely spaced bands ranging in size from less than 30 to 250 base pairs.

Spotlight on the human factor: building a foundation for the future of haemophilia A management: report from a symposium on human recombinant FVIII at the World Federation of Hemophilia World Congress, Melbourne, Australia on 12 May 2014.

Science.gov (United States)

Kessler, C; Oldenburg, J; Ettingshausen, C Escuriola; Tiede, A; Khair, K; Négrier, C; Klamroth, R

2015-01-01

Inhibitor development is the most serious and challenging complication in the treatment of severe haemophilia A. Up to 38% of such patients develop inhibitors with current recombinant factor VIII (rFVIII) products produced in hamster cell lines. Human-cl rhFVIII is a new generation fully sulfated B-domain-deleted FVIII coagulant glycoprotein, which is generated from a human cell line. Thus, there are no non-human epitopes which would be potentially immunogenic. This molecule has significantly higher VWF-binding affinity compared with existing full-length rFVIII produced in hamster cell lines. The development aim of Human-cl rhFVIII is to address the challenges of FVIII inhibitors and frequent infusions during prophylaxis. Human-cl rhFVIII's mean half-life is very comparable to some of the newer products which involve modification of the FVIII molecule to extend the circulating half-life. There are promising data concerning the use of a personalized prophylaxis regimen with Human-cl rhFVIII. Preliminary data indicate a median dosing interval of 3.5 days with 66.7% of the patients on a twice per week or fewer infusions schedule combined with a low bleeding rate and no increased FVIII consumption when compared to standard prophylaxis. No product-specific laboratory assay is required to monitor the coagulation activity for Human-cl rhFVIII. The results of registration clinical trials with Human-cl rhFVIII as well as the ongoing studies in previously untreated patients (NuProtect) and personalized prophylaxis study in previously treated patients (NuPreviq), will be discussed. The manufacturer has received marketing authorization for Human-cl rhFVIII in Europe and Canada under the name Nuwiq(®) and plans to launch it in the USA and globally in 2015. © 2014 John Wiley & Sons Ltd.

Multimeric and trimeric subunit SP-D are interconvertible structures with distinct ligand interaction

DEFF Research Database (Denmark)

Sørensen, Grith Lykke; Hoegh, Silje V; Leth-Larsen, Rikke

2009-01-01

-D compared to Met11 SP-D. Multimerization has proven important for enhancement of microbial phagocytosis. In the present study defined multimeric forms of Met11Thr SP-D were isolated from human amniotic fluid. Implementation of ManNAc-affinity chromatography allowed high recovery of natural trimeric SP......-D multimers. Trimeric SP-D subunits also showed greater binding to endogenous lipoproteins: LDL, oxLDL, and HDL, than multimeric SP-D. In conclusion, purified trimeric and multimeric SP-D represent separate and only partly interconvertible molecular populations with distinct biochemical properties....

A direita que saiu do armário: a cosmovisão dos formadores de opinião dos manifestantes de direita brasileiros

OpenAIRE

Messenberg, Débora

2018-01-01

O artigo procura desvelar a cosmovisão (weltanschauung) dos principais formadores de opinião dos manifestantes de direita brasileiros, que foram as ruas ao longo do ano de 2015. O trabalho pautou-se em pesquisa multimétodos, construída a partir do levantamento das postagens emitidas por esses atores sociais em suas páginas no Facebook, durante o ano em foco, além de matérias de suas autorias publicadas em blogs, jornais e revistas, como também vídeos de suas entrevistas e hangouts. Organizara...

O programa Estúdio Móvel da TV Brasil no Facebook

OpenAIRE

Rozados, Helen Beatriz Frota; Corrêa, Rochele Tonello Zago

2013-01-01

Este artigo trata do uso do Facebook por programa de televisão pública. O objetivo geral é compreender com que finalidade o Estúdio Móvel da TV Brasil utiliza a rede social virtual Facebook, contextualizando a TV Pública Brasileira, a TV Brasil, o Núcleo Multimídia (NUMID) e o programa Estúdio Móvel. Apresenta o conceito de TV Social, convergência transmídia de conteúdos e o Estúdio Móvel no Facebook. Discute a metodologia aplicada e os resultados da pesquisa. Considera que os conteúdos compa...

The interrelationship between ligand binding and thermal unfolding of the folate binding protein. The role of self-association and pH

DEFF Research Database (Denmark)

Holm, Jan; Babol, Linnea N.; Markova, Natalia

2014-01-01

The present study utilized a combination of DLS (dynamic light scattering) and DSC (differential scanning calorimetry) to address thermostability of high-affinity folate binding protein (FBP), a transport protein and cellular receptor for the vitamin folate. At pH7.4 (pI=7-8) ligand binding......, intermolecular forces involved in concentration-dependent multimerization thus contribute to the thermostability of holo-FBP. Hence, thermal unfolding and dissociation of holo-FBP multimers occur simultaneously consistent with a gradual decrease from octameric to monomeric holo-FBP (10μM) in DLS after a step-wise...

La pareja pedagógica: Una estrategia para transitar y aprender el oficio de ser profesor

OpenAIRE

Rodríguez Zidán, Eduardo; Grilli Silva, Javier

2013-01-01

Este informe analiza la modalidad “pareja pedagógica” como un nuevo dispositivo en la formación de profesores de Educación Media. El estudio se realizó en el Centro Regional de Profesores (CeRP) del Litoral a partir del relevo de opiniones de estudiantes, profesores y directores desde un enfoque multimétodo. Las técnicas utilizadas fueron la encuesta autoadministrada y las entrevistas episódicas. Se aplicó un cuestionario a setenta y cinco estudiantes y se realizaron once entrevistas a inform...

“Multimity”: intimate performances from adolescents of Buenos Aires in Facebook

Directory of Open Access Journals (Sweden)

Joaquín Linne

2016-05-01

Full Text Available This article discusses the intimate performances that display adolescents of the City of Buenos Aires through the social network Facebook. The methodology consists of a mixed ethnography: first, conducting content analysis of thirty in-depth interviews with adolescents of the universe of study and also face-to-face and virtual observations. Among the results, daily performances that publish everyday adolescents are described and the concept multimity (“multimidad” is proposed to account for the ways in which they build and share their privacy in the digital platform.

Conflitos organizacionais: a utilização da Educação a Distância para ensinar esse conteúdo nos Cursos de Graduação da Área da Saúde

OpenAIRE

Spagnol, Carla Aparecida; Guimarães, Eliane Marina Palhares; Godoy, Solange Cervinho Bicalho; Marques, Renata Lacerda

2015-01-01

O tema conflito organizacional é difícil de ser trabalhado somente com aulas expositivas, pois é um fenômeno que depende da situação, das pessoas envolvidas e do contexto em que ocorreu. Atualmente as tecnologias educacionais digitais são utilizadas em cursos na modalidade presencial ou a distância, tornando-se indispensável utilizar metodologias ativas. Este artigo é um relato de experiência que tem o objetivo de descrever e analisar uma disciplina a distância, que utiliza um material multim...

Comunidad Hispana de Everquest 2

OpenAIRE

Ybáñez Domínguez, Ainhoa

2011-01-01

Comunidad Hispana de Everquest 2 programada en PHP, incluye administración propia de secciones, integración con login de foro vBulletin 4, integración con login de galería multimedia Coppermine, e integración con login de wiki Mediawiki de forma parcial. Comunitat Hispana d'Everquest 2 programada en PHP, inclou administració pròpia de seccions, integració amb identificació a fòrum vBulletin 4, integració amb identificació a galeria multimèdia Coppermine, i integració amb identificació a wi...

Evaluación de una intervención mediante sofrología para disminuir la ansiedad en las gestantes con un feto con retraso de crecimiento

OpenAIRE

Arranz Betegón, Ángela; Montenegro Nadal, Gala; García Moliner, Marta; Roldán, A. (Aurora); Camacho Sáez, Alba; García, Milagros; Goberna Tricas, Josefina; Botet Mussons, Francisco; Gratacós Solsona, Eduard

2017-01-01

Objetivo: comparar el grado de ansiedad de un grupo de mujeres con un feto con retraso de crecimiento intrauterino (RCIU) visitadas exclusivamente por especialistas en medicina maternofetal en relación a otras mujeres que, además, también fueron visitadas por una matrona formada en técnicas de relajación y detectar los sentimientos prevalentes cuando se informa del diagnóstico. Material y método: estudio multimétodo: cuantitativo (diseño cuasi-experimental) y cualitativo (fenomenológico). Las...

Influence of the Corporate Social Responsibility initiatives on the psychosocial well-being of workers

OpenAIRE

Mari Ripa, Daniel

2016-01-01

La presente Tesis Doctoral analiza la influencia de las iniciativas de la Responsabilidad Social Corporativa (RSC) de las empresas en la salud, seguridad y bienestar de los trabajadores. Para ello, se utiliza una orientación multimétodo, que incluye análisis cualitativos y cuantitativos así como diversas fuentes de datos. En primer lugar, se examina el grado en que 27 estándares de evaluación de RSC cubren las condiciones laborales, a través de una extensa revisión, y qué áreas...

Human umbilical cord blood-derived f-macrophages retain pluripotentiality after thrombopoietin expansion

International Nuclear Information System (INIS)

Zhao Yong; Mazzone, Theodore

2005-01-01

We have previously characterized a new type of stem cell from human peripheral blood, termed fibroblast-like macrophage (f-MΦ). Here, using umbilical cord blood as a source, we identified cells with similar characteristics including expression of surface markers (CD14, CD34, CD45, CD117, and CD163), phagocytosis, and proliferative capacity. Further, thrombopoietin (TPO) significantly stimulated the proliferation of cord blood-derived f-MΦ (CB f-MΦ) at low dosage without inducing a megakaryocytic phenotype. Additional experiments demonstrated that TPO-expanded cord blood-derived f-MΦ (TCB f-MΦ) retained their surface markers and differentiation ability. Treatment with vascular endothelial cell growth factor (VEGF) gave rise to endothelial-like cells, expressing Flt-1, Flk-1, von Willebrand Factor (vWF), CD31, acetylated low density lipoprotein internalization, and the ability to form endothelial-like cell chains. In the presence of lipopolyssacharide (LPS) and 25 mM glucose, the TCB f-MΦ differentiated to express insulin mRNA, C-peptide, and insulin. In vitro functional analysis demonstrated that these insulin-positive cells could release insulin in response to glucose and other secretagogues. These findings demonstrate a potential use of CB f-MΦ and may lead to develop new therapeutic strategy for treating dominant disease

The immediate and late effects of thyroid hormone (triiodothyronine) on murine coagulation gene transcription.

Science.gov (United States)

Salloum-Asfar, Salam; Boelen, Anita; Reitsma, Pieter H; van Vlijmen, Bart J M

2015-01-01

Thyroid dysfunction is associated with changes in coagulation. The aim of our study was to gain more insight into the role of thyroid hormone in coagulation control. C57Black/6J mice received a low-iodine diet and drinking water supplemented with perchlorate to suppress endogenous triiodothyronine (T3) and thyroxine (T4) production. Under these conditions, the impact of exogenous T3 on plasma coagulation, and hepatic and vessel-wall-associated coagulation gene transcription was studied in a short- (4 hours) and long-term (14 days) setting. Comparing euthyroid conditions (normal mice), with hypothyroidism (conditions of a shortage of thyroid hormone) and those with replacement by incremental doses of T3, dosages of 0 and 0.5 μg T3/mouse/day were selected to study the impact of T3 on coagulation gene transcription. Under these conditions, a single injection of T3 injection increased strongly hepatic transcript levels of the well-characterized T3-responsive genes deiodinase type 1 (Dio1) and Spot14 within 4 hours. This coincided with significantly reduced mRNA levels of Fgg, Serpinc1, Proc, Proz, and Serpin10, and the reduction of the latter three persisted upon daily treatment with T3 for 14 days. Prolonged T3 treatment induced a significant down-regulation in factor (F) 2, F9 and F10 transcript levels, while F11 and F12 levels increased. Activity levels in plasma largely paralleled these mRNA changes. Thbd transcript levels in the lung (vessel-wall-associated coagulation) were significantly up-regulated after a single T3 injection, and persisted upon prolonged T3 exposure. Two-week T3 administration also resulted in increased Vwf and Tfpi mRNA levels, whereas Tf levels decreased. These data showed that T3 has specific effects on coagulation, with Fgg, Serpinc1, Proc, Proz, Serpin10 and Thbd responding rapidly, making these likely direct thyroid hormone receptor targets. F2, F9, F10, F11, F12, Vwf, Tf and Tfpi are late responding genes and probably indirectly

Pulmonary endothelial activation caused by extracellular histones contributes to neutrophil activation in acute respiratory distress syndrome.

Science.gov (United States)

Zhang, Yanlin; Guan, Li; Yu, Jie; Zhao, Zanmei; Mao, Lijun; Li, Shuqiang; Zhao, Jinyuan

2016-11-21

During the acute respiratory distress syndrome (ARDS), neutrophils play a central role in the pathogenesis, and their activation requires interaction with the endothelium. Extracellular histones have been recognized as pivotal inflammatory mediators. This study was to investigate the role of pulmonary endothelial activation during the extracellular histone-induced inflammatory response in ARDS. ARDS was induced in male C57BL/6 mice by intravenous injection with lipopolysaccharide (LPS) or exogenous histones. Concurrent with LPS administration, anti-histone H4 antibody (anti-H4) or non-specific IgG was administered to study the role of extracellular histones. The circulating von Willebrand factor (vWF) and soluble thrombomodulin (sTM) were measured with ELISA kits at the preset time points. Myeloperoxidase (MPO) activity in lung tissue was measured with a MPO detection kit. The translocation of P-selectin and neutrophil infiltration were measured by immunohistochemical detection. For in vitro studies, histone H4 in the supernatant of mouse lung vascular endothelial cells (MLVECs) was measured by Western blot. The binding of extracellular histones with endothelial membrane was examined by confocal laser microscopy. Endothelial P-selectin translocation was measured by cell surface ELISA. Adhesion of neutrophils to MLVECs was assessed with a color video digital camera. The results showed that during LPS-induced ARDS extracellular histones caused endothelial and neutrophil activation, as seen by P-selectin translocation, release of vWF, an increase of circulating sTM, lung neutrophil infiltration and increased MPO activity. Extracellular histones directly bound and activated MLVECs in a dose-dependent manner. On the contrary, the direct stimulatory effect of exogenous histones on neutrophils was very limited, as measured by neutrophil adhesion and MPO activity. With the contribution of activated endothelium, extracellular histones could effectively activating

Effects of aerobic exercise and medical nutrition intervention on endothelial injury and placental blood perfusion in patients with preeclampsia

Directory of Open Access Journals (Sweden)

Zhen-Ju Zhang1

2017-06-01

Full Text Available Objective: To study the effects of aerobic exercise and medical nutrition intervention on endothelial injury and placental blood perfusion in patients with preeclampsia. Methods: 72 cases of patients diagnosed with preeclampsia in Department of Obstetrics and Gynecology of Zigong Third People’s Hospital between January 2013 and August 2016 were selected randomly divided into two groups, the observation group received aerobic exercise, medical nutrition combined with routine intervention, and the control group received routine intervention. Before and after intervention, serum endothelial injury markers were detected. After delivery, the expression of apoptosis molecules and the contents of stress molecules caused by hypoxia in placenta were detected. Results: After intervention, serum AnnexinV, vWF, ET-1 and oxLDL contents of both groups were lower than those before intervention while NO, PLGF and ABCA1 contents were higher than those before intervention and serum AnnexinV, vWF, ET-1 and oxLDL contents of observation group were lower than those of control group while NO, PLGF and ABCA1 contents were higher than those of control group; after delivery, Bax, Fas, FasL and Caspase-3 mRNA expression as well as MDA, AOPP, CHOP and GRP78 protein contents in placenta of observation group were lower than those of control group. Conclusion: Aerobic exercise and medical nutrition intervention can reduce the endothelial injury and improve the placental hypoxia of preeclampsia.

Post-mortem assessment of hypoperfusion of cerebral cortex in Alzheimer's disease and vascular dementia.

Science.gov (United States)

Thomas, Taya; Miners, Scott; Love, Seth

2015-04-01

Perfusion is reduced in the cerebral neocortex in Alzheimer's disease. We have explored some of the mechanisms, by measurement of perfusion-sensitive and disease-related proteins in post-mortem tissue from Alzheimer's disease, vascular dementia and age-matched control brains. To distinguish physiological from pathological reduction in perfusion (i.e. reduction exceeding the decline in metabolic demand), we measured the concentration of vascular endothelial growth factor (VEGF), a protein induced under conditions of tissue hypoxia through the actions of hypoxia-inducible factors, and the myelin associated glycoprotein to proteolipid protein 1 (MAG:PLP1) ratio, which declines in chronically hypoperfused brain tissue. To evaluate possible mechanisms of hypoperfusion, we also measured the levels of amyloid-β40, amyloid-β42, von Willebrand factor (VWF; a measure of microvascular density) and the potent vasoconstrictor endothelin 1 (EDN1); we assayed the activity of angiotensin I converting enzyme (ACE), which catalyses the production of another potent vasoconstrictor, angiotensin II; and we scored the severity of arteriolosclerotic small vessel disease and cerebral amyloid angiopathy, and determined the Braak tangle stage. VEGF was markedly increased in frontal and parahippocampal cortex in Alzheimer's disease but only slightly and not significantly in vascular dementia. In frontal cortex the MAG:PLP1 ratio was significantly reduced in Alzheimer's disease and even more so in vascular dementia. VEGF but not MAG:PLP1 increased with Alzheimer's disease severity, as measured by Braak tangle stage, and correlated with amyloid-β42 and amyloid-β42: amyloid-β40 but not amyloid-β40. Although MAG:PLP1 tended to be lowest in cortex from patients with severe small vessel disease or cerebral amyloid angiopathy, neither VEGF nor MAG:PLP1 correlated significantly with the severity of structural vascular pathology (small vessel disease, cerebral amyloid angiopathy or VWF

Une réalisation de l’apprentissage partagé dans un environnement multimédia Une réalisation de l’apprentissage partagé dans un environnement multimédia

Directory of Open Access Journals (Sweden)

Colette Mrowa-Hopkins

2000-12-01

Full Text Available Dans la mesure où l’utilisation des technologies nouvelles est adaptée aux besoins d’un apprentissage individualisé, les enseignants de langues sont contraints de réévaluer leur propre savoir-faire pédagogique. Il convient de se demander dans quelle mesure la dynamique sociale qui caractérise les échanges dans un climat de travail en collaboration autour de l’ordinateur peut être plus enrichissante pour l’apprentissage des langues. Plus particulièrement, en ce qui nous concerne, dans quelle mesure cette dynamique peut favoriser la performance orale par rapport à un travail de groupe dans une classe traditionnelle. Le présent article offre une perspective nouvelle sur le potentiel d’apprentissage que peut apporter l’utilisation des technologies de l’information et de la communication.This paper attempts, firstly, to document the nature of the linguistic exchanges between pairs of intermediate and advanced students of French who engage in interactive tasks in a CALL environment; and, secondly, it examines the extent to which that interaction is relevant to second-language learning by way of comparison with a small-group, task-based, interaction in a traditional oral class, involving students of the same level of competence. In a search for methods for describing and evaluating CALL use, this exploratory investigation provides support for the adoption of an ’interactionist’ perspective which claims that the language of the participants is central to learning, and that the use of discourse analysis methods is helpful. It is anticipated that computer-mediated interaction shares with a traditional face-to-face contact many of the same interactional features which are believed to make oral negotiation beneficial to learning. However, as this small-scale study suggests, the potential of computer-mediated interaction to facilitate language learning is seen as stemming from a combination of the interactive features of conversation with reflective aspects of learning as participants co-construct knowledge with their more or less experienced peers.

Characteristics of endothelial dysfunction in patients with gout comorbid with arterial hypertension

Directory of Open Access Journals (Sweden)

N. A. Zolotariova

2016-06-01

  Abstract Currently there is scarce data on endothelial dysfunction (ED in patients with gout (GA, moreover there are no current studies of ED in gout comorbid with arterial hypertension (AH. The purpose of this study is to describe specific features of biochemical and instrumental markers of endothelial dysfunction in patients with GA comorbid with AH. We measured and compared the level of Von Willebrand factor (vWF, interleukin-1beta (IL-1, endothelin-1 (ET-1, plasma nitrites (NO2- and nitrates (NO3-, the total activity of NO-synthase, endothelium-dependent (FMD and endothelium-independent vasodilatation (NMD in 26 patients with GA, 26 patients with AH and in 86 patients with GA+AH. The study showed that vWF concentration was highest in comorbidity group (92,9±29,0% showing no significant difference from GA and AH (79,2% and   86,5% respectively. IL-1 was highest in GA+AH group (2,0 pg/ml being significantly higher than in AH (p=0,01 but showing no difference from GA (p=1,0. ET-1 concentration was highest in the comorbid pathology group (3,07 fmol/ml versus 1,58 fmol/ml in GA (p<0,0001 and 2,77 fmol/ml in AH (p=1,0. NO-synthase activity was greatest in GA and in comorbid pathology groups showing no significant intergroup difference; NO2- and NO3- concentrations, being similar in these two groups, were statistically higher that in AH. Greatest reduction of FMD and NMD was found in comorbid pathology group (5,80% and 10,35% respectively and it was not significantly different from AH group (6,18%; p=0,83 for FMD and 13,59%; p=0,079 for NMD. FMD and NMD in gout (10,03% and 15,35% respectively were similar to normal, being significantly different compared to GA+AH group (p=0,045 for FMD and p=0,018 for NMD. This study shows that ED in gout is characterized by significantly higher concentration of IL-1, nitric oxide metabolites and intact FMD compared to hypertension. Hypertension is characterized by significantly higher concentrations of endothelin-1, more

Activation of 125I-Factor IX and 125I-Factor X: Effect of tissue factor and Factor VII, Factor Xsub(a) and thrombin

International Nuclear Information System (INIS)

Oesterud, B.; Rapaport, S.I.

Activation of Factor IX and Factor X was studied by adding 125 I-Factor IX or 125 I-Factor X to reaction mixtures and quantitating cleavage products by reduced sodium dodecylsulfate gel electrophoresis. Thrombin failed to activate Factors IX or X; Factor Xsub(a) produced insignificant amounts of cleavage products of both factors. In contrast, the reaction product of tissue factor and Factor VII cleaved large amounts of both Factor IX and Factor X in purified systems and in plasma. In incubation mixtures of plasma containing added 125 I-Factor IX or 125 I-Factor X, tissue factor and Ca 2+ ions, the percentage of total radioactivity in the heavy chain peak of 125 I-IXsub(a) and the heavy chain of 125 I-Xsub(a) increased at a similar rate. When the tissue factor was diluted, similar curves were obtained for percent cleavage of 125 I-Factor IX and percent cleavage of 125 I-Factor X plotted against tissue factor concentration. These findings support the hypothesis that activation of Factor IX by the tissue factor-Factor VII reaction product represents a physiologically significant step in normal haemostasis. (author)

Cyclosporin A Impairs the Secretion and Activity of ADAMTS13 (A Disintegrin and Metalloprotease with Thrombospondin Type 1 Repeat)*

Science.gov (United States)

Hershko, Klilah; Simhadri, Vijaya L.; Blaisdell, Adam; Hunt, Ryan C.; Newell, Jordan; Tseng, Sandra C.; Hershko, Alon Y.; Choi, Jae Won; Sauna, Zuben E.; Wu, Andrew; Bram, Richard J.; Komar, Anton A.; Kimchi-Sarfaty, Chava

2012-01-01

The protease ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 repeat) cleaves multimers of von Willebrand factor, thus regulating platelet aggregation. ADAMTS13 deficiency leads to the fatal disorder thrombotic thrombocytopenic purpura (TTP). It has been observed that cyclosporin A (CsA) treatment, particularly in transplant patients, may sometimes be linked to the development of TTP. Until now, the reason for such a link was unclear. Here we provide evidence demonstrating that cyclophilin B (CypB) activity plays an important role in the secretion of active ADAMTS13. We found that CsA, an inhibitor of CypB, reduces the secretion of ADAMTS13 and leads to conformational changes in the protein resulting in diminished ADAMTS13 proteolytic activity. A direct, functional interaction between CypB (which possesses peptidyl-prolyl cis-trans isomerase (PPIase) and chaperone functions) and ADAMTS13 is demonstrated using immunoprecipitation and siRNA knockdown of CypB. Finally, CypB knock-out mice were found to have reduced ADAMTS13 levels. Taken together, our findings indicate that cyclophilin-mediated activity is an important factor affecting secretion and activity of ADAMTS13. The large number of proline residues in ADAMTS13 is consistent with the important role of cis-trans isomerization in the proper folding of this protein. These results altogether provide a novel mechanistic explanation for CsA-induced TTP in transplant patients. PMID:23144461

Cyclosporin A impairs the secretion and activity of ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 repeat).

Science.gov (United States)

Hershko, Klilah; Simhadri, Vijaya L; Blaisdell, Adam; Hunt, Ryan C; Newell, Jordan; Tseng, Sandra C; Hershko, Alon Y; Choi, Jae Won; Sauna, Zuben E; Wu, Andrew; Bram, Richard J; Komar, Anton A; Kimchi-Sarfaty, Chava

2012-12-28

The protease ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 repeat) cleaves multimers of von Willebrand factor, thus regulating platelet aggregation. ADAMTS13 deficiency leads to the fatal disorder thrombotic thrombocytopenic purpura (TTP). It has been observed that cyclosporin A (CsA) treatment, particularly in transplant patients, may sometimes be linked to the development of TTP. Until now, the reason for such a link was unclear. Here we provide evidence demonstrating that cyclophilin B (CypB) activity plays an important role in the secretion of active ADAMTS13. We found that CsA, an inhibitor of CypB, reduces the secretion of ADAMTS13 and leads to conformational changes in the protein resulting in diminished ADAMTS13 proteolytic activity. A direct, functional interaction between CypB (which possesses peptidyl-prolyl cis-trans isomerase (PPIase) and chaperone functions) and ADAMTS13 is demonstrated using immunoprecipitation and siRNA knockdown of CypB. Finally, CypB knock-out mice were found to have reduced ADAMTS13 levels. Taken together, our findings indicate that cyclophilin-mediated activity is an important factor affecting secretion and activity of ADAMTS13. The large number of proline residues in ADAMTS13 is consistent with the important role of cis-trans isomerization in the proper folding of this protein. These results altogether provide a novel mechanistic explanation for CsA-induced TTP in transplant patients.

Carotid intima-media thickness in children with end-stage renal disease on dialysis.

Science.gov (United States)

Gheissari, A; Sirous, M; Hajzargarbashi, T; Kelishadi, R; Merrikhi, A; Azhir, A

2010-01-01

Cardiovascular morbidity and mortality are common in end stage renal disease (ESRD) patients. There is scarce data on carotid and bulb intima-media thickness (IMT-C and IMT-B) as an early marker of atherosclerosis and related factors in children on hemodialysis (HD) and peritoneal dialysis (PD). Since we did not have enough information about our patients, this study was carried on all ESRD children (hemodialysis and peritoneal dialysis) in a referral center. Data was collected from 16 ESRD children under 18 years with seven patients on PD and nine on HD. Lab tests and biochemical parameters including serum von Willebrand factor (vWF), homocystein, apo lipoprotein A, apo lipoprotein B and quantitative CRP were measured in fasting patients just before initiating dialysis. IMT-C and IMT-B were measured by gray scale ultrasound using 7.5 MHZ probe. The mean of age was 12.76+/-4.5 years. The mean duration of dialysis in HD and PD patients were not significantly different; 11.88+/-3.25 months and 10.14+/-2.4 months respectively. Mean of systolic blood pressure in HD group was significantly higher than PD group, 135.55+/-25.54 mmHg versus 121.42+/-12.14 mmHg, Phomocystein and IMT-C. However, we could not demonstrate any difference between IMT-B in case and control group. After adjusting for age, partial correlation showed significant correlation between IMT-C and following factors: N-PTH and serum alkaline phosphatase. Longitudinal studies with large size samples are needed to clarify the contributing factors with intima-media thickness in ESRD children.

Las Competencias Informacionales: Un marco para el desarrollo del aprendizaje autónomo

OpenAIRE

Fúquene Bolaños, Sandra Viviana; Cabrales, Omar

2016-01-01

En el siglo XXI la tecnología y la sociedad globalizada han modificado la manera en cómo se aprende, los modos de vida y el acceso al conocimiento. En la educación superior, por ejemplo, estos cambios se reflejan en la incorporación de aparatos digitales en el aula de clase. Así, la investigación diagnostica por medio de encuestas y entrevistas cuáles son las competencias informacionales de los estudiantes de la Facultad de Ingeniería, de los programas Civil, Industrial, Mecatrónica y Multime...

Serviços pós-4G em redes de satélite com recepção multi-pacote de acesso com agendamento

OpenAIRE

Santos, Eduardo Jorge dos

2012-01-01

Dissertação para obtenção do Grau de Mestre em Engenharia Eletrotécnica e Computadores Redes de satélites farão parte das futuras redes integradas de comunicações, proporcionando cobertura ubíqua e grande resiliência. Estas redes complementam a infraestrutura celular terrestre, suportando serviços ubíquos de dados e multimédia com garantias de qualidade de serviço (QoS). A simples retransmissão de pacotes perdidos, devido ao descarte dos mesmos em caso de colisão, leva à degradação do d...

Méthodes d'analyse/synthèse et représentations optimales des sons musicaux basées sur la réduction de données spectrales

OpenAIRE

Rochebois , Thierry

1997-01-01

This thesis introduces a method that allows systematic reduction of data representing musical sounds. This method and its variants allows fast and dynamic synthesis of musical sounds.; Les applications de l'analyse et de la synthèse des sons musicaux sont primordiales a l'heure du multimédia. Nous présentons une méthode permettant d'analyser et de synthétiser les sons musicaux. Cette méthode, illustrée au chapitre 2, se décompose en trois étapes. La première repose sur une analyse spectrale p...

El rol de la mascota publicitària en l'era de la comunicació digital

OpenAIRE

Serra Leiva, Albert

2016-01-01

Aquest projecte pretén explorar el món de les mascotes publicitàries, com s'han relacionat amb la societat des de la seva creació i quins vincles s'hi estableixen actualment mitjançant les possibilitats comunicatives i multimèdia de les noves tecnologies. A més de fer un recorregut històric fins als seus orígens, aprofundirem també en com es pensa, es dissenya i s'articula una mascota corporativa com a pilar central d'un pla de comunicació d’una marca de galetes infantils ecològiques. Este...

Uma contribuição pedagógica acerca da criação e utilização dos objetos de aprendizagem na capacitação do controlador de tráfego aéreo

OpenAIRE

Elaine Pires de Abreu

2014-01-01

Este trabalho trata do uso de objetos de aprendizagem (OA) na formação e treinamento continuado de controladores de tráfego aéreo. A capacitação das pessoas que trabalham no controle de tráfego aéreo é um importante fator de segurança operacional. Partindo das teorias de aprendizagem de adultos, colaborativa, significativa e multimídia, a pesquisa toma como referência as metodologias LODAS e ISD-ADDIE para propor um método inovador de desenvolvimento e utilização de OA para uso na formação e ...

Programação funcional usando Java

OpenAIRE

Jorge Juan Zavaleta Gavidia

1997-01-01

Desde a introdução da World Wide Web para o mundo nos inícios de 1990, usando a Internet como uma rede para transferir dados, empregando uma forma de expressão chamada de Hipertexto, a qual liga as informações relacionadas e combinadas com multimídia, os Webs resultantes têm aberto novas possibilidades de expressão e comunicação. A quantidade de tráfego de dados na Web e o número de computadores ofertando informação vem crescendo dramaticamente, mas falta expressividade e qualidade interativa...

Governança e gestão florestal no Acre : instituições e atores em busca do desenvolvimento sustentável

OpenAIRE

Franke, Idésio Luis

2013-01-01

A Amazônia constitui-se num dos maiores patrimônios do Brasil e da humanidade por causa da riqueza da biodiversidade e dos recursos minerais e hídricos. A governança e gestão florestal constituem-se num desafio, face à necessidade do uso e conservação desse recurso e a devastação recente. Esta tese tem como objetivo descrever e analisar o quadro institucional e a visão dos atores envolvidos na gestão florestal no Acre. Foi utilizada a abordagem multimétodos em...

Construcció d'un HTPC basat en programari lliure

OpenAIRE

Ribugent Navarro, Gerard

2010-01-01

Els avenços tecnològics en els camps de la informàtica i l'entreteniment ha evolucionat molt ràpidament els darrers anys. Els ordinadors han augmentat la seva potència, han anat adquirint capacitats multimèdia i han arribat al punt de poder reproduir tranquil·lament els nous formats d'alta definició. El televisors i reproductors han passat un procés de sofisticació, el qual els ha dotat de noves característiques, com el teletext, el suport per les funcionalitats de la tdt i capacitat...

La premsa valenciana en la primera dècada del segle XXI

OpenAIRE

Martínez Sanchis, Francesc; González i Montserrat Jurado, José Luis; Doménech Fabregat, Hugo

2011-01-01

La premsa valenciana d'informació general en la primera dècada del segle XXI es caracteritza per l'aposta multimèdia dels grans diaris regionals, el domini del castellà com a llengua de comunicació i una forta expansió deis periódics gratuïts impresos i els diaris digitals. La premsa actual continua tenint la província com a límit. No hi ha una premsa regional de forta implantació en tot el territori valencià. In the first decade of the 21st century, the Valencia...

Diffusion d'informations dans les autobus par couplage de technologies wifi et satellitaires

OpenAIRE

GRANSART, C; AMBELLOUIS, S; RIOULT, J

2004-01-01

Dans cet article, nous présentons les résultats d'un projet de recherche visant à fournir de l'information en temps réel aux usagers des transports en commun de type autobus. Nous montrons que de nouveaux services innovants peuvent être développés à l'attention des objets mobiles avec une bonne qualité de service (avec une bande passante moyenne ou élevée), et un accès à l'information, au contenu multimédia et aux bases de données. Ce projet utilise un couplage de technologies innovantes pour...

N-(4-Chlorophenyl-2-(hydroxyiminoacetamide

Directory of Open Access Journals (Sweden)

Jie Sun

2009-09-01

Full Text Available The title compound, C8H7ClN2O2, is an intermediate in the synthesis of 5-chloroisatin, which can be further transformed to 5-chloro-2-indolinone via a Wolff–Kishne reduction. The C2N acetamide plane forms a dihedral angle of 6.3 (3° with the benzene ring. An intramolecular C—H...O interaction results in the formation of a six-membered ring. In the crystal, intermolecular N—H...O, N—H...N and O—H...O hydrogen bonds link the molecules into multimers, forming sheets.

Estudo empírico do desempenho dos modelos de gestão de filas FIFO, WFQ e CBWFQ em sistemas reais

OpenAIRE

Sousa, Celso; Fonte, Alexandre

2017-01-01

As aplicações multimédia (e.g., voz ou vídeo) exigem às redes IP um serviço de comunicação com baixa latência, baixas taxas de perdas de pacotes, e requisitos mínimos de largura de banda. Diferentes arquiteturas de Qualidade de Serviço (QoS) foram propostas e desenvolvidas por dois grupos do IETF, o modelo IntServ e o modelo, um pouco mais recente, DiffServ. Os fabricantes de equipamento de rede adotaram as suas próprias implementações destes modelos nos seus equipamentos de encaminhamento IP...

Protocoles d'accès multiple orientés qualité de service en constellation de satellite à orbite basse

OpenAIRE

Ibrahim , Abbas

2002-01-01

Pendant les dernières années, le réseau cellulaire est devenu accessible presque partout. Pour compléter ce réseau cellulaire terrestre, plusieurs systèmes basés sur des satellites à basse orbite (LEO Low Earth Orbit) et moyenne orbite (MEO Medium Earth Orbit) ont été développés pour offrir une couverture globale. Les services multimédias sont largement demandés sur une échelle globale.Notre but est de développer une couche d'accès MAC au canal satellitaire tout en respectant les contraintes ...

Characterization of the coagulation profile in children with liver disease and extrahepatic portal vein obstruction or shunt.

Science.gov (United States)

Beattie, William; Magnusson, Maria; Hardikar, Winita; Monagle, Paul; Ignjatovic, Vera

2017-03-01

Research Institute; FII: factor II; FV: factor V; FVII: factor VII; FVIII: factor VIII; AT: antithrombin III; A2M: alpha-2-macroglobulin; vWF: Von Willebrand factor; PC: protein C; PS: protein S; ISTH-BAT: International Society on Thrombosis and Haemostasis Bleeding Assessment Tool.

Nonparametric Identification of Glucose-Insulin Process in IDDM Patient with Multi-meal Disturbance

Science.gov (United States)

Bhattacharjee, A.; Sutradhar, A.

2012-12-01

Modern close loop control for blood glucose level in a diabetic patient necessarily uses an explicit model of the process. A fixed parameter full order or reduced order model does not characterize the inter-patient and intra-patient parameter variability. This paper deals with a frequency domain nonparametric identification of the nonlinear glucose-insulin process in an insulin dependent diabetes mellitus patient that captures the process dynamics in presence of uncertainties and parameter variations. An online frequency domain kernel estimation method has been proposed that uses the input-output data from the 19th order first principle model of the patient in intravenous route. Volterra equations up to second order kernels with extended input vector for a Hammerstein model are solved online by adaptive recursive least square (ARLS) algorithm. The frequency domain kernels are estimated using the harmonic excitation input data sequence from the virtual patient model. A short filter memory length of M = 2 was found sufficient to yield acceptable accuracy with lesser computation time. The nonparametric models are useful for closed loop control, where the frequency domain kernels can be directly used as the transfer function. The validation results show good fit both in frequency and time domain responses with nominal patient as well as with parameter variations.

Cuadernia, una eina multimèdia per a elaborar materials didàctics

OpenAIRE

Herrera Gutierrez, Gerardo; Gregori-Signes, Carmen; Samblás Betata, Marisa; Sevilla Peris, Javier; Montes Maya, Rebeca; Abellán Royuela, Raquel

2009-01-01

Cuadernia es la herramienta con licencia Creative Commons que la Consejería de Educación y Ciencia de Castilla-La Mancha pone a disposición de toda la comunidad educativa para la creación y difusión de materiales educativos digitales con una interfaz y presentación final muy intuitiva y fácil de utilizar. Esta herramienta permite crear cuadernos digitales para utilizar en red o en tu propio ordenador. Los autores son miembros de un proyecto de investigación Authia que colabora con los creado...

Multimédia a interaktivní studijní materiály na MU

OpenAIRE

Brandejs Michal; Brandejsová Jitka; Lunter Ľuboš

2010-01-01

Již v roce 2005 implementoval vývojový tým Informačního systému Masarykovy univerzity (IS MU) vlastní nástroje pro elektronickou podporu výuky (e-learningové nástroje) pro tvorbu a spravování kurzů. V té době se začali první učitelé, nadšeni těmito nástroji v IS MU, věnovat zavádění elektronických aktivit do svých předmětů. Postupné zkušenosti ukázaly, že pokud chce univerzita nabídnout svým studenům kvalitní a moderní elektronické studijní materiály, je nutné dlouhodobé vzdělávání a metodick...

Ultrasound assessment of mitral annular displacement in patients with coronary heart disease and its correlation with left heart function and serum indexes

Directory of Open Access Journals (Sweden)

Bing-Yan Lai

2016-10-01

Full Text Available Objective: To analyze the ultrasound assessment of mitral annular displacement in patients with coronary heart disease and its correlation with left heart function and serum indexes. Methods: A total of 89 patients with coronary heart disease were divided into angina pectoris group 42 cases and myocardial infarction group 47 cases according to the illness, and 58 cases of healthy subjects were included in control group. Values of mitral annular displacement (MAD parameters, left heart function indexes and serum illness-related indexes of three groups were detected, and the correlation between values of MAD parameters and values of cardiac function indexes and serum illness-related indexes were further analyzed. Results: MAD parameters TMAD1, TMAD2 and TMADmid values, heart function LVEF values and serum CysC level of myocardial infarction group and angina pectoris group were lower than those of control group, and cardiac function LVEDD, LVESD and A/E values as well as serum H-FABP, ICTP, Hcy and vWF levels were higher than those of control group (P<0.05; MAD parameters TMAD1, TMAD2 and TMADmid values of patients with coronary heart disease were negatively correlated with LVEDD, LVESD and A/E values as well as H-FABP, ICTP, Hcy and vWF levels, and were positively correlated with LVEF value and CysC level (P<0.05. Conclusions: Ultrasound assessment of mitral annular displacement in patients with coronary heart disease can early diagnose coronary heart disease and judge the disease severity, and it plays a positive role in optimizing disease prognosis.

Down-regulation of selected Blood-brain Barrier Specific Genes from Capillaries to Bovine In Vitro Models

DEFF Research Database (Denmark)

Goldeman, Charlotte; Saaby, Lasse; Brodin, Birger

Cultures of primary bovine brain endothelial cells (BECs) grown, often together with astrocytes, on permeable supports in two-compartment culture systems are commonly used as an in vitro model of the blood-brain barrier (BBB). While trans-endothelial electrical resistance, restriction...... the in vivo gene expression of brain capillary endothelial cells. Primary bovine endothelial cells and rat astrocytes were cultured in different culture configurations and the mRNA expression of selected genes (vWF, Glut-1, P-gp, claudin-1,-5, occludin, JAM-1, LAT-1, SLC16A1, MRP-1,-4, BCRP, ZO-1, AP, TPA...

Improved endothelial function and lipid profile compensate for impaired hemostatic and inflammatory status in iatrogenic chronic subclinical hyperthyroidism of thyroid cancer patients on L-t4 therapy.

Science.gov (United States)

Gazdag, A; Nagy, E V; Burman, K D; Paragh, G; Jenei, Z

2010-06-01

We aimed to compare the changes of endothelial function and haemostatic, inflammatory and metabolic parameters of short-term iatrogenic hypothyroidism to the characteristics of subclinical hyperthyroidism in patients with differentiated thyroid cancer. Twenty four women (mean age 42.4+/-8.1 years) had undergone total thyroidectomy and radioiodine ablation in treatment for differentiated thyroid cancer. We measured serum thyroglobulin, thyroid function, plasma levels of lipid parameters, homocystine, C-reactive protein, fibrinogen, von Willebrandt factor activity (vWF), nitric oxide, as well as flow-mediated vasodilatation (FMD) and nitroglycerin-mediated vasodilatation of the brachial artery during iatrogenic hypothyroidism (TSH 89.82+/-29.36 mU/L) and again in the same patients during subclinical hyperthyroidism secondary to exogenous levothyroxine administration (TSH 0.24+/-0.11 mU/L). In hypothyroidism, FMD was markedly lower than in subclinical hyperthyroidism (6.79+/-4.44 vs. 14.37+/-8.33%, phyperthyroidism was associated with improved endothelial function and lipid profile, while haemostatic and inflammatory parameters were impaired. The two opposite mechanisms may well compensate for each other at the level of the vessel wall. (c) J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart, New York.

Serviço de apoio a distância ao professor em sala de aula pela tv digital interativa

Directory of Open Access Journals (Sweden)

José Manuel Martin Rios

2004-01-01

Full Text Available Este é um artigo de um projeto em andamento desenvolvido em parceria com a Diretoria Técnica de Serviços do CPqD Telecom & IT Solutions e a Faculdade de Educação da UNICAMP, que objetiva estabelecer um serviço de apoio a distância aos professores em sala de aula em 03 Escolas da região de Barão Geraldo em Campinas/ SP , para utilizar a TV Digital Interativa como ferramenta de busca e desenvolvimento de conteúdo multimídia interativo nas práticas pedagógicas. Fundamentalmente esta ferramenta será de fácil uso por utilizar como terminal de escolha e exibição um televisor colocado nas salas de aula das escolas e controlado por controle remoto. O professor poderá interagir com o conteúdo exibido no televisor de modo a obter uma programação não linear que se desenvolverá conforme o seu projeto pedagógico. As principais características do serviço são a facilidade de uso, fornecimento a distância de material multimídia interativo, baixo custo de implantação e grande área geográfica de cobertura, proporcionada pela disponibilidade quase total de sinal de televisão no território nacional. Este serviço é parte de um conjunto de serviços de teleducação que estão sendo desenvolvidos para o futuro Sistema de TV Digital terrestre que será implantado no Brasil.

4D Art: corpos reais e virtuais, uma realidade aumentada

Directory of Open Access Journals (Sweden)

Michel Lemieux

2016-05-01

Full Text Available A companhia canadense 4D Art fascina o olhar do público e interroga seus sentidos de realidade e presença pela interação cênica dos movimentos de corpos reais e virtuais. Para compreender os processos de criação da cena multimídia de 4D Art, apresenta-se uma entrevista exclusiva realizada com os diretores artísticos Michel Lemieux e Victor Pilon. As motivações artísticas do jogo real e virtual, os procedimentos empregados na criação das figuras virtuais e os desafios enfrentados pelos atores aparecem nas palavras dos criadores.

Avaliação numérica da comunicação de vídeo em redes ATM com enlace sem fio.

OpenAIRE

Donisete Magri

1998-01-01

Nos últimos anos, tem-se considerado as redes Wireless ATM como sendo uma infra-estrutura potencial para a quarta geração de redes de comunicação wireless, capaz de suportar serviços multimídia integrados com diferentes requisitos de qualidade de serviço (QoS). Os dois aspectos mais críticos das redes Wireless ATM são o protocolo de controle de acesso ao meio (MAC) e a técnica de controle de admissão de chamadas (CAC), usados pelos terminais móveis e pela estação base para fornecer serviços c...

A utilização das novas tecnologias na formação e divulgação de conteúdos : em particular o vídeo no Youtube

OpenAIRE

Costa, Manuel Domingos Veloso Pereira da

2011-01-01

Dissertação de mestrado em Ciências da Comunicação (área de especialização em Audiovisual e Multimédia) Na nova Era da Web, apelidada de 2.0, despoletaram um conjunto de aplicações e serviços, de entre os quais se destacou o Youtube. Neste documento, são exploradas as principais características deste serviço de armazenamento e partilha de vídeos, é abordado o sistema de publicação e de utilização de tags, os problemas legais relativos aos direitos de autor e as normas do You...

Caroline Surmann, Cinéma et théâtre chez Jean Cocteau. Intermédialité et esthétique

OpenAIRE

Brangé, Mireille

2016-01-01

Dans une démarche artistique considérée comme essentiellement multimédiale et «déambulant entre les arts» (p. 12), la relation établie entre cinéma et théâtre par Cocteau est un terrain de choix pour envisager sa pratique intermédiale. L’A. précise ce concept travaillé d’abord en Allemagne et au Canada et le plus souvent seulement approché en France, et offre une introduction théorique appréciable (pp. 13-15; 47-67) en l’absence, à notre connaissance, de toute traduction française des textes ...

Uma proposta de instrumento de roteirização de videoaulas à luz da teoria instrucional e da aprendizagem multimídia

Directory of Open Access Journals (Sweden)

Vinicius Carvalho Pereira

2017-06-01

ABSTRACT: The contemporary educational scenario witnesses an exponential growth of distance education, where print materials stand out in terms of research, production and distribution. However, the spread of audiovisual resources in cyberculture, as well as the emergence of new paradigms of teaching and learning, demands researches on didactic materials in other medias. This research aims at identifying guidelines for a scripting tool that empowers teachers as active members throughout the production of audiovisual didactic materials. In terms of methodology, we designed a scripting tool based on instructional theories and theories of multimedia learning. Five teachers were given that instrument to write the script of a simple videoclass about a daily activity. Then, the research subjects were interviewed for a qualitatively assessing of the scripting tool, in order to validate/reformulate it. The results from the interviews and from the analyses of the tools suggest that such an instrument can allow teachers to better understand the videoclass production process. Besides, it was possible to elicit some factors that should be adapted to improve the scripting tool. Besides, we noticed that some multimedia learning principles were not respected by research subjects when they were scripting their videoclasses, which suggests the need to clarify the scripting tool.

Alteration of human umbilical vein endothelial cell gene expression in different biomechanical environments.

Science.gov (United States)

Shoajei, Shahrokh; Tafazzoli-Shahdpour, Mohammad; Shokrgozar, Mohammad Ali; Haghighipour, Nooshin

2014-05-01

Biomechanical environments affect the function of cells. In this study we analysed the effects of five mechanical stimuli on the gene expression of human umbilical vein endothelial cells (HUVECs) in mRNA level using real-time PCR. The following loading regimes were applied on HUVECs for 48 h: intermittent (0-5 dyn/cm(2) , 1 Hz) and uniform (5 dyn/cm(2) ) shear stresses concomitant by 10% intermittent equiaxial stretch (1 Hz), uniform shear stress alone (5 dyn/cm(2) ), and intermittent uniaxial and equiaxial stretches (10%, 1 Hz). A new bioreactor was made to apply uniform/cyclic shear and tensile loadings. Three endothelial suggestive specific genes (vascular endothelial growth factor receptor-2 (VEGFR-2, also known as FLK-1), von Willebrand Factor (vWF) and vascular endothelial-cadherin (VE-cadherin)), and two smooth muscle genes (α-smooth muscle actin (α-SMA) and smooth muscle myosin heavy chain (SMMHC)) were chosen for assessment of alteration in gene expression of endothelial cells and transdifferentiation toward smooth cells following load applications. Shear stress alone enhanced the endothelial gene expression significantly, while stretching alone was identified as a transdifferentiating factor. Cyclic equiaxial stretch contributed less to elevation of smooth muscle genes compared to uniaxial stretch. Cyclic shear stress in comparison to uniform shear stress concurrent with cyclic stretch was more influential on promotion of endothelial genes expression. Influence of different mechanical stimuli on gene expression may open a wider horizon to regulate functions of cell for tissue engineering purposes. © 2013 International Federation for Cell Biology.

Tissue factor-dependent activation of tritium-labeled factor IX and factor X in human plasma

International Nuclear Information System (INIS)

Morrison, S.A.; Jesty, J.

1984-01-01

A comparism was made of the tissue factor-dependent activation of tritium-labeled factor IX and factor X in a human plasma system and a study was made of the role of proteases known to stimulate factor VII activity. Plasma was defibrinated by heating and depleted of its factors IX and X by passing it through antibody columns. Addition of human brain thromboplastin, Ca2+, and purified 3H-labeled factor X to the plasma resulted, after a short lag, in burst-like activation of the factor X, measured as the release of radiolabeled activation peptide. The progress of activation was slowed by both heparin and a specific inhibitor of factor Xa but factor X activation could not be completely abolished by such inhibitors. In the case of 3H-factor IX activation, the rate also increased for approximately 3 min after addition of thromboplastin, but was not subsequently curtailed. A survey of proteases implicated as activators of factor VII in other settings showed that both factor Xa and factor IXa could accelerate the activation of factor IX. However, factor Xa was unique in obliterating activation when present at concentrations greater than approximately 1 nM. Heparin inhibited the tissue factor-dependent activation of factor IX almost completely, apparently through the effect of antithrombin on the feedback reactions of factors Xa and IXa on factor VII. These results suggest that a very tight, biphasic control of factor VII activity exists in human plasma, which is modulated mainly by factor Xa. At saturation of factor VIIa/tissue factor, factor IX activation was significantly more rapid than was previously found in bovine plasma under similar conditions. The activation of factor X at saturation was slightly more rapid than in bovine plasma, despite the presence of heparin

Hypoxia precondition promotes adipose-derived mesenchymal stem cells based repair of diabetic erectile dysfunction via augmenting angiogenesis and neuroprotection.

Directory of Open Access Journals (Sweden)

XiYou Wang

Full Text Available The aim of the present study was to examine whether hypoxia preconditioning could improve therapeutic effects of adipose derived mesenchymal stem cells (AMSCs for diabetes induced erectile dysfunction (DED. AMSCs were pretreated with normoxia (20% O2, N-AMSCs or sub-lethal hypoxia (1% O2, H-AMSCs. The hypoxia exposure up-regulated the expression of several angiogenesis and neuroprotection related cytokines in AMSCs, including vascular endothelial growth factor (VEGF and its receptor FIK-1, angiotensin (Ang-1, basic fibroblast growth factor (bFGF, brain-derived neurotrophic factor (BDNF, glial cell-derived neurotrophic factor (GDNF, stromal derived factor-1 (SDF-1 and its CXC chemokine receptor 4 (CXCR4. DED rats were induced via intraperitoneal injection of streptozotocin (60 mg/kg and were randomly divided into three groups-Saline group: intracavernous injection with phosphate buffer saline; N-AMSCs group: N-AMSCs injection; H-AMSCs group: H-AMSCs injection. Ten rats without any treatment were used as normal control. Four weeks after injection, the mean arterial pressure (MAP and intracavernosal pressure (ICP were measured. The contents of endothelial, smooth muscle, dorsal nerve in cavernoursal tissue were assessed. Compared with N-AMSCs and saline, intracavernosum injection of H-AMSCs significantly raised ICP and ICP/MAP (p<0.05. Immunofluorescent staining analysis demonstrated that improved erectile function by MSCs was significantly associated with increased expression of endothelial markers (CD31 and vWF (p<0.01 and smooth muscle markers (α-SMA (p<0.01. Meanwhile, the expression of nNOS was also significantly higher in rats receiving H-AMSCs injection than those receiving N-AMSCs or saline injection. The results suggested that hypoxic preconditioning of MSCs was an effective approach to enhance their therapeutic effect for DED, which may be due to their augmented angiogenesis and neuroprotection.

Molecular and clinical profile of von Willebrand disease in Spain (PCM-EVW-ES): comprehensive genetic analysis by next-generation sequencing of 480 patients.

Science.gov (United States)

Borràs, Nina; Batlle, Javier; Pérez-Rodríguez, Almudena; López-Fernández, María Fernanda; Rodríguez-Trillo, Ángela; Lourés, Esther; Cid, Ana Rosa; Bonanad, Santiago; Cabrera, Noelia; Moret, Andrés; Parra, Rafael; Mingot-Castellano, María Eva; Balda, Ignacia; Altisent, Carme; Pérez-Montes, Rocío; Fisac, Rosa María; Iruín, Gemma; Herrero, Sonia; Soto, Inmaculada; de Rueda, Beatriz; Jiménez-Yuste, Víctor; Alonso, Nieves; Vilariño, Dolores; Arija, Olga; Campos, Rosa; Paloma, María José; Bermejo, Nuria; Berrueco, Rubén; Mateo, José; Arribalzaga, Karmele; Marco, Pascual; Palomo, Ángeles; Sarmiento, Lizheidy; Iñigo, Belén; Nieto, María Del Mar; Vidal, Rosa; Martínez, María Paz; Aguinaco, Reyes; César, Jesús María; Ferreiro, María; García-Frade, Javier; Rodríguez-Huerta, Ana María; Cuesta, Jorge; Rodríguez-González, Ramón; García-Candel, Faustino; Cornudella, Rosa; Aguilar, Carlos; Vidal, Francisco; Corrales, Irene

2017-12-01

Molecular diagnosis of patients with von Willebrand disease is pending in most populations due to the complexity and high cost of conventional molecular analyses. The need for molecular and clinical characterization of von Willebrand disease in Spain prompted the creation of a multicenter project (PCM-EVW-ES) that resulted in the largest prospective cohort study of patients with all types of von Willebrand disease. Molecular analysis of relevant regions of the VWF , including intronic and promoter regions, was achieved in the 556 individuals recruited via the development of a simple, innovative, relatively low-cost protocol based on microfluidic technology and next-generation sequencing. A total of 704 variants (237 different) were identified along VWF , 155 of which had not been previously recorded in the international mutation database. The potential pathogenic effect of these variants was assessed by in silico analysis. Furthermore, four short tandem repeats were analyzed in order to evaluate the ancestral origin of recurrent mutations. The outcome of genetic analysis allowed for the reclassification of 110 patients, identification of 37 asymptomatic carriers (important for genetic counseling) and re-inclusion of 43 patients previously excluded by phenotyping results. In total, 480 patients were definitively diagnosed. Candidate mutations were identified in all patients except 13 type 1 von Willebrand disease, yielding a high genotype-phenotype correlation. Our data reinforce the capital importance and usefulness of genetics in von Willebrand disease diagnostics. The progressive implementation of molecular study as the first-line test for routine diagnosis of this condition will lead to increasingly more personalized and effective care for this patient population. Copyright© 2017 Ferrata Storti Foundation.

Factors and factorizations of graphs proof techniques in factor theory

CERN Document Server

Akiyama, Jin

2011-01-01

This book chronicles the development of graph factors and factorizations. It pursues a comprehensive approach, addressing most of the important results from hundreds of findings over the last century. One of the main themes is the observation that many theorems can be proved using only a few standard proof techniques. This stands in marked contrast to the seemingly countless, complex proof techniques offered by the extant body of papers and books. In addition to covering the history and development of this area, the book offers conjectures and discusses open problems. It also includes numerous explanatory figures that enable readers to progressively and intuitively understand the most important notions and proofs in the area of factors and factorization.

Limestone Creek, Local Flood Protection, Fayetteville, New York

Science.gov (United States)

1990-08-01

maple, slippery elm , syca- more, black locust, dogwood, sumac, choke cherry, creeping cucumber, goldenrod and teasel. Wooded areas on the surrounding...CIRCLE C. -AkA- BARKER t LANE IVIALL KEN 4A AVE 2 7rflEE EEOER r ’A CHANIC S ENWOOD LANE Shcoping cc a ttev Center RNE -V ELM STREET GENES STREET...0~i r; 0 i cyO n 0 00.- w ~ 0vwf N - N 9 00 0 , - 00 -l N NO w IV a,0 200 000 -0 a, r. elm ID MW PN0NIN MOJn 0m M e. 0’iamo 0 q0 ON T0 Fw% N..NV

Biocompatibility of Poly-ε-caprolactone-hydroxyapatite composite on mouse bone marrow-derived osteoblasts and endothelial cells

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Wooley Paul H

2009-02-01

Full Text Available Abstract Background Tissue-engineered bone may be developed by seeding the cells capable of both osteogenesis and vascularization on biocompatible composite scaffolds. The current study investigated the performance of mice bone marrow-derived osteogenic cells and endothelial cells as seeded on hydroxyapatite (HA and poly-ε-caprolactone (PCL composite scaffolds. Methods Mononuclear cells were induced to osteoblasts and endothelial cells respectively, which were defined by the expression of osteocalcin, alkaline phosphatase (ALP, and deposits of calcium-containing crystal for osteoblasts, or by the expression of vascular endothelial growth factor receptor-2 (VEGFR-2 and von Willebrand factor (vWF, and the formation of a capillary network in Matrigel™ for endothelial cells. Both types of cell were seeded respectively on PCL-HA scaffolds at HA to PCL weight ratio of 1:1, 1:4, or 0:1 and were evaluated using scanning electron microscopy, ALP activity (of osteoblasts and nitric oxide production (of endothelial cells plus the assessment of cell viability. Results The results indicated that HA led to a positive stimulation of osteoblasts viability and ALP activity, while HA showed less influence on endothelial cells viability. An elevated nitric oxide production of endothelial cells was observed in HA-containing group. Conclusion Supplement of HA into PCL improved biocompatible for bone marrow-derived osteoblasts and endothelial cells. The PCL-HA composite integrating with two types of cells may provide a useful system for tissue-engineered bone grafts with vascularization.

Factor XII (Hageman factor) deficiency

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/000545.htm Factor XII (Hageman factor) deficiency To use the sharing features on this ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

Natural plasmid transformation in a high-frequency-of transformation marine Vibrio strain

International Nuclear Information System (INIS)

Frischer, M.E.; Thurmond, J.M.; Paul, J.H.

1990-01-01

The estuarine bacterium Vibrio strain DI-9 has been shown to be naturally transformable with both broad host range plasmid multimers and homologous chromosomal DNA at average frequencies of 3.5 x 10 -9 and 3.4 x 10 -7 transformants per recipient, respectively. Growth of plasmid transformants in nonselective medium resulted in cured strains that transformed 6 to 42,857 times more frequently than the parental strain, depending on the type of transforming DNA. These high-frequency-of-transformation (HfT) strains were transformed at frequencies ranging from 1.1 x 10 -8 to 1.3 x 10 -4 transformants per recipient with plasmid DNA and at an average frequency of 8.3 x 10 -5 transformants per recipient with homologous chromosomal DNA. The highest transformation frequencies were observed by using multimers of an R1162 derivative carrying the transposon Tn5 (pQSR50). Probing of total DNA preparations from one of the cured strains demonstrated that no plasmid DNA remained in the cured strains which may have provided homology to the transforming DNA. All transformants and cured strains could be differentiated from the parental strains by colony morphology. DNA binding studies indicated that late-log-phase HfT strains bound [ 3 H]bacteriophage lambda DNA 2.1 times more rapidly than the parental strain. These results suggest that the original plasmid transformation event of strain DI-9 was the result of uptake and expression of plasmid DNA by a competent mutant (HfT strain). Additionally, it was found that a strain of Vibrio parahaemolyticus, USFS 3420, could be naturally transformed with plasmid DNA. Natural plasmid transformation by high-transforming mutants may be a means of plasmid acquisition by natural aquatic bacterial populations

Structural and Functional Characterization of a Single-chain Peptide-MHC Molecule that Modulates both Naive and Activated CD8plus T Cells

Energy Technology Data Exchange (ETDEWEB)

D Samanta; G Mukherjee; U Ramagopal; R Chaparro; S Nathenson; T DiLorenzo; S Almo

2011-12-31

Peptide-MHC (pMHC) multimers, in addition to being tools for tracking and quantifying antigen-specific T cells, can mediate downstream signaling after T-cell receptor engagement. In the absence of costimulation, this can lead to anergy or apoptosis of cognate T cells, a property that could be exploited in the setting of autoimmune disease. Most studies with class I pMHC multimers used noncovalently linked peptides, which can allow unwanted CD8{sup +} T-cell activation as a result of peptide transfer to cellular MHC molecules. To circumvent this problem, and given the role of self-reactive CD8{sup +} T cells in the development of type 1 diabetes, we designed a single-chain pMHC complex (scK{sup d}.IGRP) by using the class I MHC molecule H-2K{sup d} and a covalently linked peptide derived from islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP{sub 206-214}), a well established autoantigen in NOD mice. X-ray diffraction studies revealed that the peptide is presented in the groove of the MHC molecule in canonical fashion, and it was also demonstrated that scK{sup d}.IGRP tetramers bound specifically to cognate CD8{sup +} T cells. Tetramer binding induced death of naive T cells and in vitro- and in vivo-differentiated cytotoxic T lymphocytes, and tetramer-treated cytotoxic T lymphocytes showed a diminished IFN-{gamma} response to antigen stimulation. Tetramer accessibility to disease-relevant T cells in vivo was also demonstrated. Our study suggests the potential of single-chain pMHC tetramers as possible therapeutic agents in autoimmune disease. Their ability to affect the fate of naive and activated CD8{sup +} T cells makes them a potential intervention strategy in early and late stages of disease.

The aldo-keto reductase superfamily homepage.

Science.gov (United States)

Hyndman, David; Bauman, David R; Heredia, Vladi V; Penning, Trevor M

2003-02-01

The aldo-keto reductases (AKRs) are one of the three enzyme superfamilies that perform oxidoreduction on a wide variety of natural and foreign substrates. A systematic nomenclature for the AKR superfamily was adopted in 1996 and was updated in September 2000 (visit www.med.upenn.edu/akr). Investigators have been diligent in submitting sequences of functional proteins to the Web site. With the new additions, the superfamily contains 114 proteins expressed in prokaryotes and eukaryotes that are distributed over 14 families (AKR1-AKR14). The AKR1 family contains the aldose reductases, the aldehyde reductases, the hydroxysteroid dehydrogenases and steroid 5beta-reductases, and is the largest. Other families of interest include AKR6, which includes potassium channel beta-subunits, and AKR7 the aflatoxin aldehyde reductases. Two new families include AKR13 (yeast aldose reductase) and AKR14 (Escherichia coli aldehyde reductase). Crystal structures of many AKRs and their complexes with ligands are available in the PDB and accessible through the Web site. Each structure has the characteristic (alpha/beta)(8)-barrel motif of the superfamily, a conserved cofactor binding site and a catalytic tetrad, and variable loop structures that define substrate specificity. Although the majority of AKRs are monomeric proteins of about 320 amino acids in length, the AKR2, AKR6 and AKR7 family may form multimers. To expand the nomenclature to accommodate multimers, we recommend that the composition and stoichiometry be listed. For example, AKR7A1:AKR7A4 (1:3) would designate a tetramer of the composition indicated. The current nomenclature is recognized by the Human Genome Project (HUGO) and the Web site provides a link to genomic information including chromosomal localization, gene boundaries, human ESTs and SNPs and much more.

Thrombotic thrombocytopenic purpura presenting with pathologic fracture: a case report.

Science.gov (United States)

Berber, Ilhami; Erkurt, Mehmet Ali; Kuku, Irfan; Kaya, Emin; Unlu, Serkan; Ertem, Kadir; Nizam, Ilknur

2014-08-01

Thrombotic thrombocytopenic purpura is an acute syndrome with abnormalities in multiple organ systems, which becomes manifest with microangiopathic hemolytic anemia and thrombocytopenia. The hereditary or acquired deficiency of ADAMTS-13 activity leads to an excess of high molecular weight von Willebrand factor multimers in plasma, leading to platelet aggregation and diffuse intravascular thrombus formation, resulting in thrombotic thrombocytopenic purpura. Thrombotic lesions occurring in TTP leads to ischemia and convulsion. Depending on the properties of the bony tissue, fractures are divided into three groups as traumatic, pathological, and stress fractures. A pathologic fracture is a broken bone caused by disease leading to weakness of the bone. This process is most commonly due to osteoporosis, but may also be due to other pathologies such as cancer, infections, inherited bone disorders, or a bone cyst. We herein report a case with a pathologic fracture due to convulsion secondary to thrombotic thrombocytopenic pupura. Thrombotic lesions occurring in TTP may lead to ischemia and convulsion, as in our patient and pathological fractures presented in our case report may occur as a result of severe muscle contractions associated with convulsive activity. Thrombotic thrombocytopenic pupura is a disease that involves many organ systems and thus may have a very wide spectrum of clinical presentations. Copyright © 2014. Published by Elsevier Ltd.

Teoría de la Aceptación-Rechazo Interpersonal (IPARTheory: bases conceptuales, método y evidencia empírica

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Ronald P. Rohner

2014-12-01

Full Text Available La teoría de aceptación-rechazo interpersonal (IPARTheory es una teoría basada en la evidencia que trata de predecir y explicar las principales causas, consecuencias y correlatos de la aceptación-rechazo -especialmente parental- a lo largo del ciclo vital. Esta teoría se divide en tres subteorías: subteoría de la personalidad (todos los niños y niñas independientemente de su contexto sociocultural, racial o étnico responden esencialmente en el mismo sentido cuando perciben que son rechazados o aceptados por sus padres u otras figuras de apego; subteoría del afrontamiento (determinados factores individuales proporcionan tanto a niños como a adultos la fortaleza de afrontar más eficazmente las experiencias de rechazo; y subteoría de los sistemas socioculturales (el rechazo parental ocurre en un contexto ecológico, más global, que abarca la familia, la comunidad y en un entorno sociocultural. El método en la IPARTheory se caracteriza por utilizar una estrategia multimétodo desde una perspectiva transcultural, y por proveer un marco conceptual para integrar los estudios empíricos sobre aceptación-rechazo interpersonal desde una perspectiva del ciclo vital.

Characterization of the expression, promoter activity and molecular architecture of fibin

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Hermsdorf Thomas

2011-05-01

Full Text Available Abstract Background Fibin was initially discovered as a secreted signal molecule essential for pectoral fin bud initiation in zebrafish. Currently, there is little information about the molecular architecture and biological relevance of fibin in humans and other mammals. Results Fibin is expressed in cerebellum, skeletal muscle and many other embryonic and adult mouse tissues suggesting not only a role during embryonic development but also in adult functions. A 2.5-kbp genomic sequence fragment upstream of the coding sequence is sufficient to drive and regulate fibin expression through stimulation by glucocorticoids, activators of the protein kinase C signalling pathways and manganese ions. Fibin is an evolutionarily conserved protein, carries a cleavable signal peptide (amino acids 1-18 and is glycosylated at Asn30. The two conserved cysteines participate in intermolecular disulfide bond and multimer formation. Although fibin displays all features of a secretory protein, it is mostly retained in the endoplasmic reticulum when heterologously expressed. Conclusion Fibin is functionally relevant during embryogenesis and adult life. Its expression is regulated by a number of cellular signalling pathways and the protein is routed via the secretory pathway. However, proper secretion presumably requires an unknown covalently-linked or associated co-factor.

Implication des partenaires dans la campagne québécoise de promotion de la santé « Défi Santé 5/30 »

OpenAIRE

Martel, Guillaume; Renaud, Lise; Caron-Bouchard, Monique; Gagnon, Louis; Pelletier, Marie-Claude

2015-01-01

Cette étude porte sur la gestion des partenariats en promotion de la santé et s’inscrit dans une étude de cas du « Défi Santé 5/30 ». Cette campagne québécoise multimédia promouvant de saines habitudes d’alimentation, d’activité physique et de maintien/modification du poids, de douze semaines, s’est déroulée en 2005. Le but de notre article est de : 1) décrire les acteurs de la campagne et leur implication  ; 2) relever l’interaction entre ces acteurs pendant le déroulement du « Défi Santé 5/...

Electron Microscopy Structural Insights into CPAP Oligomeric Behavior

DEFF Research Database (Denmark)

Alvarez-Cabrera, Ana L; Delgado, Sandra; Gil-Carton, David

2017-01-01

Centrosomal P4.1-associated protein (CPAP) is a cell cycle regulated protein fundamental for centrosome assembly and centriole elongation. In humans, the region between residues 897-1338 of CPAP mediates interactions with other proteins and includes a homodimerization domain. CPAP mutations cause...... into clearly different regular 3D maps (putatively corresponding to dimers and tetramers) and direct observation of individual images representing other complexes of HsCPAP(897-1338) (i.e., putative flexible monomers and higher-order multimers), we report a dynamic oligomeric behavior of this protein, where...... of different oligomers of CPAP, suggesting further insights to understand how this protein works, contributing to the elucidation of control mechanisms for centriole biogenesis....

Redes alimentarias alternativas en grandes ciudades: los mercados de productores agrarios en Madrid

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Ricardo Méndez Gutiérrez del Valle

2017-01-01

Full Text Available Las redes alimentarias alternativas constituyen una temática de investigación emergente en los estudios urbanos, que cuestiona los modelos dominantes de producción, distribución y consumo de alimentos. Una de sus manifestaciones son los mercados de productores, que ponen en contacto directo a productores periurbanos y rurales con consumidores urbanos, favoreciendo las relaciones de proximidad y los circuitos cortos. El artículo investiga los mercados de productores en Madrid mediante una estrategia multimétodo que combina entrevistas, encuestas y otras técnicas complementarias. Los resultados confirman su diversidad interna, identifican las estrategias de los diferentes actores y delimitan su impacto territorial, mostrando también sus limitaciones.

Overview of a HLA-Ig based "Lego-like system" for T cell monitoring, modulation and expansion.

Science.gov (United States)

Oelke, Mathias; Schneck, Jonathan P

2010-07-01

Recent advances in molecular medicine have shown that soluble MHC-multimers can be valuable tools for both analysis and modulation of antigen-specific immune responses in vitro and in vivo. In this review, we describe the use of dimeric human and mouse major histocompatibility complexes, MHC-Ig, as part of an artificial Antigen-Presenting Cell (aAPC). MHC-Ig-based aAPC and its derivatives represent an exciting new platform technology for measuring and manipulating immune responses in vitro as well as in vivo. This new technology has the potential to help overcome many of the obstacles associated with limitations in current antigen-specific approaches of immunotherapy for the treatment of cancer, infectious diseases and autoimmunity.

Factors affecting construction performance: exploratory factor analysis

Science.gov (United States)

Soewin, E.; Chinda, T.

2018-04-01

The present work attempts to develop a multidimensional performance evaluation framework for a construction company by considering all relevant measures of performance. Based on the previous studies, this study hypothesizes nine key factors, with a total of 57 associated items. The hypothesized factors, with their associated items, are then used to develop questionnaire survey to gather data. The exploratory factor analysis (EFA) was applied to the collected data which gave rise 10 factors with 57 items affecting construction performance. The findings further reveal that the items constituting ten key performance factors (KPIs) namely; 1) Time, 2) Cost, 3) Quality, 4) Safety & Health, 5) Internal Stakeholder, 6) External Stakeholder, 7) Client Satisfaction, 8) Financial Performance, 9) Environment, and 10) Information, Technology & Innovation. The analysis helps to develop multi-dimensional performance evaluation framework for an effective measurement of the construction performance. The 10 key performance factors can be broadly categorized into economic aspect, social aspect, environmental aspect, and technology aspects. It is important to understand a multi-dimension performance evaluation framework by including all key factors affecting the construction performance of a company, so that the management level can effectively plan to implement an effective performance development plan to match with the mission and vision of the company.

Proteolysis of platelet receptors in humans and other species.

Science.gov (United States)

Qiao, Jian L; Shen, Yang; Gardiner, Elizabeth E; Andrews, Robert K

2010-08-01

In the past 5 years, metalloproteinase-mediated ectodomain shedding of platelet receptors has emerged as a new mechanism for modulating platelet function. By regulating surface expression of the platelet-specific receptors, glycoprotein (GP)VI that binds collagen, and GPIbalpha (the major ligand-binding subunit of the GPIb-IX-V complex) that binds von Willebrand factor (VWF) and other procoagulant and proinflammatory ligands, shedding not only irreversibly downregulates GPVI/GPIbalpha function, but generates proteolytic fragments that might be unique biomarkers or modulators in plasma. This is potentially significant because GPVI and GPIbalpha are involved in initiating thrombotic diseases such as heart attack and stroke, as well as autoimmune diseases where anti-platelet antibodies result in thrombocytopenia. Altered expression levels of GPIbalpha/GPVI are associated with both thrombotic propensity and platelet aging, suggesting an additional role in platelet clearance. Although emerging data are elucidating molecular mechanisms underlying GPIbalpha/GPVI shedding, evidence for the functional consequences of shedding in vivo, either clinically or in animal models, is far more limited. Here we consider recent published evidence for GPVI or GPIbalpha shedding in humans, nonhuman primates and mice, and whether conservation of sheddase cleavage sites across species points to a functional role for metalloproteolytic shedding in vivo.

High throughput protease profiling comprehensively defines active site specificity for thrombin and ADAMTS13.

Science.gov (United States)

Kretz, Colin A; Tomberg, Kärt; Van Esbroeck, Alexander; Yee, Andrew; Ginsburg, David

2018-02-12

We have combined random 6 amino acid substrate phage display with high throughput sequencing to comprehensively define the active site specificity of the serine protease thrombin and the metalloprotease ADAMTS13. The substrate motif for thrombin was determined by >6,700 cleaved peptides, and was highly concordant with previous studies. In contrast, ADAMTS13 cleaved only 96 peptides (out of >10 7 sequences), with no apparent consensus motif. However, when the hexapeptide library was substituted into the P3-P3' interval of VWF73, an exosite-engaging substrate of ADAMTS13, 1670 unique peptides were cleaved. ADAMTS13 exhibited a general preference for aliphatic amino acids throughout the P3-P3' interval, except at P2 where Arg was tolerated. The cleaved peptides assembled into a motif dominated by P3 Leu, and bulky aliphatic residues at P1 and P1'. Overall, the P3-P2' amino acid sequence of von Willebrand Factor appears optimally evolved for ADAMTS13 recognition. These data confirm the critical role of exosite engagement for substrates to gain access to the active site of ADAMTS13, and define the substrate recognition motif for ADAMTS13. Combining substrate phage display with high throughput sequencing is a powerful approach for comprehensively defining the active site specificity of proteases.

Quality, Stability, and Safety Data of Packed Red Cells and Plasma Processed by Gravity Separation Using a New Fully Integrated Hollow-Fibre Filter Device

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T. Brune

2009-01-01

Full Text Available Background. We developed a completely closed system based on gravity separation without centrifugation steps for separation of whole blood. With this new system we compared quality and stability of the processed blood components (PRC and plasma with respect to classical preparation. Furthermore the cost-effectiveness of this hollow fibre system was evaluated. Study Design and Methods. Whole blood collections of 15 regular blood donors were used for component preparation using the U shaped hollow fibre filter device. Results were compared to 15 whole blood preparations using centrifugation. The following parameters were evaluated: total hemoglobin, leukocyte counts, the serum concentration of total protein, lactate dehydrogenase (LDH and potassium. Furthermore ATIII, vWF and F VIII were analyzed at different timepoints. Results. packed red cells: the data directly after separation and after 42 days of storage are in line with the guidelines of the council of Europe. Plasma. all plasma quality data are in line with the guidelines of the council of Europe for quality assurance of plasma, except for a low protein amount (factor 0.75. Conclusion. Separation of whole blood on a clinical scale in this new closed system is feasible, however the plasma protein content must be optimized.

Evaluation of Human Amniotic Membrane as a Wound Dressing for Split-Thickness Skin-Graft Donor Sites

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Denys J. Loeffelbein

2014-01-01

Full Text Available Human amniotic membrane (HAM has been used as a biomaterial in various surgical procedures and exceeds some qualities of common materials. We evaluated HAM as wound dressing for split-thickness skin-graft (STSG donor sites in a swine model (Part A and a clinical trial (Part B. Part A: STSG donor sites in 4 piglets were treated with HAM or a clinically used conventional polyurethane (PU foil (n=8 each. Biopsies were taken on days 5, 7, 10, 20, 40, and 60 and investigated immunohistochemically for alpha-smooth muscle actin (αSMA: wound contraction marker, von Willebrand factor (vWF: angiogenesis, Ki-67 (cell proliferation, and laminin (basement membrane integrity. Part B: STSG donor sites in 45 adult patients (16 female/29 male were treated with HAM covered by PU foam, solely by PU foam, or PU foil/paraffin gauze (n=15 each. Part A revealed no difference in the rate of wound closure between groups. HAM showed improved esthetic results and inhibitory effects on cicatrization. Angioneogenesis was reduced, and basement membrane formation was accelerated in HAM group. Part B: no difference in re-epithelialization/infection rate was found. HAM caused less ichor exudation and less pruritus. HAM has no relevant advantage over conventional dressings but might be a cost-effective alternative.

Activation of human factor V by factor Xa and thrombin

International Nuclear Information System (INIS)

Monkovic, D.D.; Tracy, P.B.

1990-01-01

The activation of human factor V by factor Xa and thrombin was studied by functional assessment of cofactor activity and sodium dodecyl sulfate-polycarylamide gel electrophoresis followed by either autoradiography of 125 I-labeled factor V activation products or Western blot analyses of unlabeled factor V activation products. Cofactor activity was measured by the ability of the factor V/Va peptides to support the activation of prothrombin. The factor Xa catalyzed cleavage of factor V was observed to be time, phospholipid, and calcium ion dependent, yielding a cofactor with activity equal to that of thrombin-activated factor V (factor Va). The cleavage pattern differed markedly from the one observed in the bovine system. The factor Xa activated factor V subunits expressing cofactor activity were isolated and found to consist of peptides of M r 220,000 and 105,000. Although thrombin cleaved the M r 220,000 peptide to yield peptides previously shown to be products of thrombin activation, cofactor activity did not increase. N-Terminal sequence analysis confirmed that both factor Xa and thrombin cleave factor V at the same bond to generate the M r 220,000 peptide. The factor Xa dependent functional assessment of 125 I-labeled factor V coupled with densitometric analyses of the cleavage products indicated that the cofactor activity of factor Xa activated factor V closely paralleled the appearance of the M r 220,000 peptide. The data indicate that factor Xa is as efficient an enzyme toward factor V as thrombin

A novel fibrinolytic metalloproteinase, barnettlysin-I from Bothrops barnetti (Barnett´s pitviper) snake venom with anti-platelet properties.

Science.gov (United States)

Sanchez, Eladio Flores; Richardson, Michael; Gremski, Luiza Helena; Veiga, Silvio Sanches; Yarleque, Armando; Niland, Stephan; Lima, Augusto Martins; Estevao-Costa, Maria Inácia; Eble, Johannes Andreas

2016-03-01

Viperid snake venoms contain active components that interfere with hemostasis. We report a new P-I class snake venom metalloproteinase (SVMP), barnettlysin-I (Bar-I), isolated from the venom of Bothrops barnetti and evaluated its fibrinolytic and antithrombotic potential. Bar-I was purified using a combination of molecular exclusion and cation-exchange chromatographies. We describe some biochemical features of Bar-I associated with its effects on hemostasis and platelet function. Bar-I is a 23.386 kDa single-chain polypeptide with pI of 6.7. Its sequence (202 residues) shows high homology to other members of the SVMPs. The enzymatic activity on dimethylcasein (DMC) is inhibited by metalloproteinase inhibitors e.g. EDTA, and by α2-macroglobulin. Bar-I degrades fibrin and fibrinogen dose- and time-dependently by cleaving their α-chains. Furthermore, it hydrolyses plasma fibronectin but not laminin nor collagen type I. In vitro Bar-I dissolves fibrin clots made either from purified fibrinogen or from whole blood. In contrast to many other P-I SVMPs, Bar-I is devoid of hemorrhagic activity. Also, Bar-I dose- and time-dependently inhibits aggregation of washed human platelets induced by vWF plus ristocetin and collagen (IC50=1.3 and 3.2 μM, respectively), presumably Bar-I cleaves both vWF and GPIb. Thus, it effectively inhibits vWF-induced platelet aggregation. Moreover, this proteinase cleaves the collagen-binding α2-A domain (160 kDa) of α2β1-integrin. This explains why it additionally inhibits collagen-induced platelet activation. A non-hemorrhagic but fibrinolytic metalloproteinase dissolves fibrin clots in vitro and impairs platelet function. This study provides new opportunities for drug development of a fibrinolytic agent with antithrombotic effect. Copyright © 2015 Elsevier B.V. All rights reserved.

Osteogenesis of human adipose-derived stem cells on poly(dopamine)-coated electrospun poly(lactic acid) fiber mats

Energy Technology Data Exchange (ETDEWEB)

Lin, Chi-Chang, E-mail: chichang31@thu.edu.tw; Fu, Shu-Juan

2016-01-01

Electrospinning is a versatile technique to generate large quantities of micro- or nano-fibers from a wide variety of shapes and sizes of polymer. The aim of this study is to develop functionalized electrospun nano-fibers and use a mussel-inspired surface coating to regulate adhesion, proliferation and differentiation of human adipose-derived stem cells (hADSCs). We prepared poly(lactic acid) (PLA) fibers coated with polydopamine (PDA). The morphology, chemical composition, and surface properties of PDA/PLA were characterized by SEM and XPS. PDA/PLA modulated hADSCs' responses in several ways. Firstly, adhesion and proliferation of hADSCs cultured on PDA/PLA were significantly enhanced relative to those on PLA. Increased focal adhesion kinase (FAK) and collagen I levels and enhanced cell attachment and cell cycle progression were observed upon an increase in PDA content. In addition, the ALP activity and osteocalcin of hADSCs cultured on PDA/PLA were significantly higher than seen in those cultured on a pure PLA mat. Moreover, hADSCs cultured on PDA/PLA showed up-regulation of the ang-1 and vWF proteins associated with angiogenesis differentiation. Our results demonstrate that the bio-inspired coating synthetic degradable PLA polymer can be used as a simple technique to render the surfaces of synthetic biodegradable fibers, thus enabling them to direct the specific responses of hADSCs. - Highlights: • A simple method of preparing electrospun poly(lactic acid) nanofibers coated with polydopamine • Enhanced adhesion and proliferation of hADSCs on a PDA/PLA mat • Increased focal adhesion kinase (FAK), collagen I levels, cell attachment and cell cycle progression with a high PDA content • Up-regulation of the Ang-1 and vWF proteins associated with angiogenesis differentiation of hADSCs is observed. • A promising method for bio-inspired surface modification on organic fiber substrates using PDA.

Osteogenesis of human adipose-derived stem cells on poly(dopamine)-coated electrospun poly(lactic acid) fiber mats

International Nuclear Information System (INIS)

Lin, Chi-Chang; Fu, Shu-Juan

2016-01-01

Electrospinning is a versatile technique to generate large quantities of micro- or nano-fibers from a wide variety of shapes and sizes of polymer. The aim of this study is to develop functionalized electrospun nano-fibers and use a mussel-inspired surface coating to regulate adhesion, proliferation and differentiation of human adipose-derived stem cells (hADSCs). We prepared poly(lactic acid) (PLA) fibers coated with polydopamine (PDA). The morphology, chemical composition, and surface properties of PDA/PLA were characterized by SEM and XPS. PDA/PLA modulated hADSCs' responses in several ways. Firstly, adhesion and proliferation of hADSCs cultured on PDA/PLA were significantly enhanced relative to those on PLA. Increased focal adhesion kinase (FAK) and collagen I levels and enhanced cell attachment and cell cycle progression were observed upon an increase in PDA content. In addition, the ALP activity and osteocalcin of hADSCs cultured on PDA/PLA were significantly higher than seen in those cultured on a pure PLA mat. Moreover, hADSCs cultured on PDA/PLA showed up-regulation of the ang-1 and vWF proteins associated with angiogenesis differentiation. Our results demonstrate that the bio-inspired coating synthetic degradable PLA polymer can be used as a simple technique to render the surfaces of synthetic biodegradable fibers, thus enabling them to direct the specific responses of hADSCs. - Highlights: • A simple method of preparing electrospun poly(lactic acid) nanofibers coated with polydopamine • Enhanced adhesion and proliferation of hADSCs on a PDA/PLA mat • Increased focal adhesion kinase (FAK), collagen I levels, cell attachment and cell cycle progression with a high PDA content • Up-regulation of the Ang-1 and vWF proteins associated with angiogenesis differentiation of hADSCs is observed. • A promising method for bio-inspired surface modification on organic fiber substrates using PDA

The small heat shock proteins from Acidithiobacillus ferrooxidans: gene expression, phylogenetic analysis, and structural modeling

Directory of Open Access Journals (Sweden)

Ribeiro Daniela A

2011-12-01

Full Text Available Abstract Background Acidithiobacillus ferrooxidans is an acidophilic, chemolithoautotrophic bacterium that has been successfully used in metal bioleaching. In this study, an analysis of the A. ferrooxidans ATCC 23270 genome revealed the presence of three sHSP genes, Afe_1009, Afe_1437 and Afe_2172, that encode proteins from the HSP20 family, a class of intracellular multimers that is especially important in extremophile microorganisms. Results The expression of the sHSP genes was investigated in A. ferrooxidans cells submitted to a heat shock at 40°C for 15, 30 and 60 minutes. After 60 minutes, the gene on locus Afe_1437 was about 20-fold more highly expressed than the gene on locus Afe_2172. Bioinformatic and phylogenetic analyses showed that the sHSPs from A. ferrooxidans are possible non-paralogous proteins, and are regulated by the σ32 factor, a common transcription factor of heat shock proteins. Structural studies using homology molecular modeling indicated that the proteins encoded by Afe_1009 and Afe_1437 have a conserved α-crystallin domain and share similar structural features with the sHSP from Methanococcus jannaschii, suggesting that their biological assembly involves 24 molecules and resembles a hollow spherical shell. Conclusion We conclude that the sHSPs encoded by the Afe_1437 and Afe_1009 genes are more likely to act as molecular chaperones in the A. ferrooxidans heat shock response. In addition, the three sHSPs from A. ferrooxidans are not recent paralogs, and the Afe_1437 and Afe_1009 genes could be inherited horizontally by A. ferrooxidans.

Synaptic control of local translation: the plot thickens with new characters.

Science.gov (United States)

Thomas, María Gabriela; Pascual, Malena Lucía; Maschi, Darío; Luchelli, Luciana; Boccaccio, Graciela Lidia

2014-06-01

The production of proteins from mRNAs localized at the synapse ultimately controls the strength of synaptic transmission, thereby affecting behavior and cognitive functions. The regulated transcription, processing, and transport of mRNAs provide dynamic control of the dendritic transcriptome, which includes thousands of messengers encoding multiple cellular functions. Translation is locally modulated by synaptic activity through a complex network of RNA-binding proteins (RBPs) and various types of non-coding RNAs (ncRNAs) including BC-RNAs, microRNAs, piwi-interacting RNAs, and small interference RNAs. The RBPs FMRP and CPEB play a well-established role in synaptic translation, and additional regulatory factors are emerging. The mRNA repressors Smaug, Nanos, and Pumilio define a novel pathway for local translational control that affects dendritic branching and spines in both flies and mammals. Recent findings support a role for processing bodies and related synaptic mRNA-silencing foci (SyAS-foci) in the modulation of synaptic plasticity and memory formation. The SyAS-foci respond to different stimuli with changes in their integrity thus enabling regulated mRNA release followed by translation. CPEB, Pumilio, TDP-43, and FUS/TLS form multimers through low-complexity regions related to prion domains or polyQ expansions. The oligomerization of these repressor RBPs is mechanistically linked to the aggregation of abnormal proteins commonly associated with neurodegeneration. Here, we summarize the current knowledge on how specificity in mRNA translation is achieved through the concerted action of multiple pathways that involve regulatory ncRNAs and RBPs, the modification of translation factors, and mRNA-silencing foci dynamics.

Factorization and non-factorization in diffractive hard scattering

International Nuclear Information System (INIS)

Berera, Arjun

1997-01-01

Factorization, in the sense defined for inclusive hard scattering, is discussed for diffractive hard scattering. A factorization theorem similar to its inclusive counterpart is presented for diffractive DIS. For hadron-hadron diffractive hard scattering, in contrast to its inclusive counterpart, the expected breakdown of factorization is discussed. Cross section estimates are given from a simple field theory model for non-factorizing double-pomeron-exchange (DPE) dijet production with and without account for Sudakov suppression

Low doses of flagellin-L2 multimer vaccines protect against challenge with diverse papillomavirus genotypes.

Science.gov (United States)

Kalnin, Kirill; Tibbitts, Timothy; Yan, Yanhua; Stegalkina, Svetlana; Shen, Lihua; Costa, Victor; Sabharwal, Robert; Anderson, Stephen F; Day, Patricia M; Christensen, Neil; Schiller, John T; Jagu, Subhashini; Roden, Richard B S; Almond, Jeffrey; Kleanthous, Harold

2014-06-12

Genetically modified bacterial flagellin (Fla), a Toll-like receptor-5 (TLR5) ligand, was evaluated as a fusion partner for human papillomavirus (HPV) L2-based immunogens in two animal challenge models; either cutaneous inoculation of rabbits with HPV 'quasivirions' containing cottontail rabbit papillomavirus (CRPV) genomes that induce warts, or intra-vaginal inoculation of mice with HPV 'pseudovirions' encapsidating a luciferase reporter plasmid and measurement of bioluminescence to determine infectivity. An Escherichia coli production system was developed for flagellin-L2 (Fla-L2) fusions containing either monomeric HPV-16 L2 a.a. 11(×11-200) or oligomeric L2 comprising a fusion of the a.a. 11-88 peptides of five (Fla∼5×11-88) or eight (Fla∼8×11-88) genital HPV types. Immunogenicity and bioactivity of Fla-L2 constructs were assessed using an in vitro neutralization and cell-based TLR-5 binding assay, respectively. Efficacy was evaluated following active immunization of rabbits or mice administered 3 intramuscular doses of Fla-L2 recombinants without exogenous adjuvant, followed by challenge. In addition, passive immunization studies of naïve rabbits with serial dilutions of pooled immune sera were used to determine End-Point Protection Titers (EPPT) for each formulation against a broader spectrum of HPV quasivirions. Efficacy was assessed for up to 10 weeks on the basis of wart volume induced following challenge and results compared to licensed L1-VLP vaccines (Gardasil and Cervarix). Following active immunization at doses as low as 1 μg, Fla-L2 fusions afforded complete protection against infection (mice) and disease (rabbits) following either homologous or heterologous HPV challenge. Passive immunization with anti-L2 immune sera discriminated between the different vaccine candidates under evaluation, demonstrated the protective role of antibody and suggested the superiority of this oligomeric L2-TLR5 agonist fusion approach compared to L1-based vaccines in its ability to cross-protect against non-vaccine HPV types. Copyright © 2014 Elsevier Ltd. All rights reserved.

Estratégias multimídia de incentivo à leitura: estudo do caso Dom Casmurro

Directory of Open Access Journals (Sweden)

Fátima Cristina Regis Martins de Oliveira

2015-05-01

Full Text Available O objetivo deste artigo é apresentar estratégias de recursos multimidiáticos para promover o hábito e o prazer à leitura. Para isso, é feita a análise do caso da obra Dom Casmurro, de Machado de Assis, divulgada em diversos produtos e suportes (mashup de livros, seriados, audiolivro, livroclip, que exploram múltiplas sensorialidades, linguagens e formas de narrativa. Diante da dificuldade do ensino tradicional com o tema, almeja-se atrair os jovens para a leitura da obra original.

Crystal Structure of Human Factor VIII: Implications for the Formation of the Factor IXa-Factor VIIIa Complex

Energy Technology Data Exchange (ETDEWEB)

Ngo, J.C.; Huang, M.; Roth, D.A.; Furie, B.C.; Furie, B. (Wyeth); (MBL)

2008-06-03

Factor VIII is a procofactor that plays a critical role in blood coagulation, and is missing or defective in hemophilia A. We determined the X-ray crystal structure of B domain-deleted human factor VIII. This protein is composed of five globular domains and contains one Ca{sup 2+} and two Cu{sup 2+} ions. The three homologous A domains form a triangular heterotrimer where the A1 and A3 domains serve as the base and interact with the C2 and C1 domains, respectively. The structurally homologous C1 and C2 domains reveal membrane binding features. Based on biochemical studies, a model of the factor IXa-factor VIIIa complex was constructed by in silico docking. Factor IXa wraps across the side of factor VIII, and an extended interface spans the factor VIII heavy and light chains. This model provides insight into the activation of factor VIII and the interaction of factor VIIIa with factor IXa on the membrane surface.

Crystal Structure of Human Factor VIII: Implications for the Formation of the Factor IXa-Factor VIIIa Complex

Energy Technology Data Exchange (ETDEWEB)

Chi Ki Ngo,J.; Huang, M.; Roth, D.; Furie, B.; Furie, B.

2008-01-01

Factor VIII is a procofactor that plays a critical role in blood coagulation, and is missing or defective in hemophilia A. We determined the X-ray crystal structure of B domain-deleted human factor VIII. This protein is composed of five globular domains and contains one Ca(2+) and two Cu(2+) ions. The three homologous A domains form a triangular heterotrimer where the A1 and A3 domains serve as the base and interact with the C2 and C1 domains, respectively. The structurally homologous C1 and C2 domains reveal membrane binding features. Based on biochemical studies, a model of the factor IXa-factor VIIIa complex was constructed by in silico docking. Factor IXa wraps across the side of factor VIII, and an extended interface spans the factor VIII heavy and light chains. This model provides insight into the activation of factor VIII and the interaction of factor VIIIa with factor IXa on the membrane surface.

Activation of factor VII bound to tissue factor: A key early step in the tissue factor pathway of blood coagulation

International Nuclear Information System (INIS)

Rao, L.V.M.; Rapaport, S.I.

1988-01-01

Whether the factor VII/tissue factor complex that forms in tissue factor-dependent blood coagulation must be activated to factor VIIa/tissue factor before it can activate its substrates, factor X and IX, has been a difficult question to answer because the substrates, once activated, back-activate factor VII. The earlier studies suggested that human factor VII/tissue factor cannot activate factor IX. Studies have now been extended to the activation of factor X. Reaction mixtures were made with purified factor VII, X, and tissue factor; in some experiments antithrombin III and heparin were added to prevent back-activation of factor VII. Factor X was activated at similar rates in reaction mixtures containing either VII or factor VIIa after an initial 30-sec lag with factor VII. In reaction mixtures with factor VII a linear activation of factor X was established several minutes before cleavage of 125 I-labeled factor VII to the two-chain activated molecule was demonstrable on gel profiles. These data suggest that factor VII/tissue factor cannot activate measurable amounts of factor X over several minutes. Overall, the results support the hypothesis that a rapid preferential activation of factor VII bound to tissue factor by trace amounts of factor Xa is a key early step in tissue factor-dependent blood coagulation

Activation of factor VII bound to tissue factor: a key early step in the tissue factor pathway of blood coagulation.

OpenAIRE

Rao, L V; Rapaport, S I

1988-01-01

Whether the factor VII/tissue factor complex that forms in tissue factor-dependent blood coagulation must be activated to factor VIIa/tissue factor before it can activate its substrates, factor X and factor IX, has been a difficult question to answer because the substrates, once activated, back-activate factor VII. Our earlier studies suggested that human factor VII/tissue factor cannot activate factor IX. Studies have now been extended to the activation of factor X. Reaction mixtures were ma...

Cultura e Clima Organizacional: Liderança e motivação para o sucesso

Directory of Open Access Journals (Sweden)

Ana Ventura

2012-09-01

Full Text Available O livro Cultura e Clima Organizacional: Contributos da Motivação e das competências de Gestão de Líderes, lançado pelo Professor Doutor Carlos Gonçalves, reflete um estudo de caso realizado sobre o Gabinete Coordenador de Educação Artística (GCEA, atualmente designado como Direção de Serviços de Educação Artística e Multimédia, integrado na Secretaria Regional da Educação e Recursos Humanos, da Direção Regional da Educação. Numa versão simplificada e resumida, as Edições Pedago apresentam a tese de doutoramento defendida pelo autor na Universidade de Cádiz.

Structure and dynamics of olefin radical cation aggregates. Time-resolved fluorescence detected magnetic resonance

International Nuclear Information System (INIS)

Desrosiers, M.F.; Trifunac, A.D.

1986-01-01

The time-resolved EPR spectra and thus the structure and dynamics of transient hydrocarbon radical cations are obtained by the pulse radiolysis-fluorescence detected magnetic resonance (FDMR) technique. Here the authors report the observation of short-lived radical cations from olefins. FDMR-EPR spectra of radical cations from tetramethylethylene and cyclohexadiene are illustrated. The olefin radical cations, FDMR spectra are concentration-dependent, since dimerization with neutral molecules takes place at higher (>10 -2 M) olefin concentration. Rate constants for the dimerization reaction are derived and the effect of solvent viscosity on aggregate formation is demonstrated. By monitoring the further reactions of dimer cations the authors have obtained EPR evidence for previously unobserved higher-order (multimer) radical cation aggregates of olefins. 16 references, 5 figures

Les évolutions de la norme électrique

CERN Document Server

Gallauziaux, Thierry

2014-01-01

Découvrez pièce par pièce les évolutions de la norme électrique (NF C 15-100 applicable depuis le 1er juin 2003), et les équipements minimaux requis : nombre de socles de prises de courant, emplacement des points d'éclairages, prises de communication... Sachez choisir les nouveaux dispositifs de protection des circuits, désormais obligatoires : les interrupteurs différentiels de type A, les dispositifs de coupure du fil pilote des chauffages électriques, le parafoudre... Ce qu'il faut savoir sur les nouvelles prises téléphoniques et le réseau de communication domestique pour accueillir les nouveaux services multimédias et de communication (téléphonie, TV, Internet...).

Risk Factors

Science.gov (United States)

... cells do not invade nearby tissues or spread. Risk Factors Key Points Factors That are Known to ... chemicals . Factors That are Known to Increase the Risk of Cancer Cigarette Smoking and Tobacco Use Tobacco ...

Effects of a single bout of strenuous exercise on platelet activation in female ApoE/LDLR-/- mice.

Science.gov (United States)

Przyborowski, K; Kassassir, H; Wojewoda, M; Kmiecik, K; Sitek, B; Siewiera, K; Zakrzewska, A; Rudolf, A M; Kostogrys, R; Watala, C; Zoladz, J A; Chlopicki, S

2017-11-01

Strenuous physical exercise leads to platelet activation that is normally counterbalanced by the production of endothelium-derived anti-platelet mediators, including prostacyclin (PGI 2 ) and nitric oxide (NO). However, in the case of endothelial dysfunction, e.g. in atherosclerosis, there exists an increased risk for intravascular thrombosis during exercise that might be due to an impairment in endothelial anti-platelet mechanisms. In the present work, we evaluated platelet activation at rest and following a single bout of strenuous treadmill exercise in female ApoE/LDLR - /- mice with early (3-month-old) and advanced (7-month-old) atherosclerosis compared to female age-matched WT mice. In sedentary and post-exercise groups of animals, we analyzed TXB 2 generation and the expression of platelet activation markers in the whole blood ex vivo assay. We also measured pre- and post-exercise plasma concentration of 6-keto-PGF 1α , nitrite/nitrate, lipid profile, and blood cell count. Sedentary 3- and 7-month-old ApoE/LDLR - /- mice displayed significantly higher activation of platelets compared to age-matched wild-type (WT) mice, as evidenced by increased TXB 2 production, expression of P-selectin, and activation of GPIIb/IIIa receptors, as well as increased fibrinogen and von Willebrand factor (vWf) binding. Interestingly, in ApoE/LDLR - /- but not in WT mice, strenuous exercise partially inhibited TXB 2 production, the expression of activated GPIIb/IIIa receptors, and fibrinogen binding, with no effect on the P-selectin expression and vWf binding. Post-exercise down-regulation of the activated GPIIb/IIIa receptor expression and fibrinogen binding was not significantly different between 3- and 7-month-old ApoE/LDLR - /- mice; however, only 7-month-old ApoE/LDLR - /- mice showed lower TXB 2 production after exercise. In female 4-6-month-old ApoE/LDLR - /- but not in WT mice, an elevated pre- and post-exercise plasma concentration of 6-keto-PGF 1α was observed. In turn

Determining the Number of Factors in P-Technique Factor Analysis

Science.gov (United States)

Lo, Lawrence L.; Molenaar, Peter C. M.; Rovine, Michael

2017-01-01

Determining the number of factors is a critical first step in exploratory factor analysis. Although various criteria and methods for determining the number of factors have been evaluated in the usual between-subjects R-technique factor analysis, there is still question of how these methods perform in within-subjects P-technique factor analysis. A…

Heparanase enhances the generation of activated factor X in the presence of tissue factor and activated factor VII.

Science.gov (United States)

Nadir, Yona; Brenner, Benjamin; Fux, Liat; Shafat, Itay; Attias, Judith; Vlodavsky, Israel

2010-11-01

Heparanase is an endo-β-D-glucuronidase dominantly involved in tumor metastasis and angiogenesis. Recently, we demonstrated that heparanase is involved in the regulation of the hemostatic system. Our hypothesis was that heparanase is directly involved in activation of the coagulation cascade. Activated factor X and thrombin were studied using chromogenic assays, immunoblotting and thromboelastography. Heparanase levels were measured by enzyme-linked immunosorbent assay. A potential direct interaction between tissue factor and heparanase was studied by co-immunoprecipitation and far-western assays. Interestingly, addition of heparanase to tissue factor and activated factor VII resulted in a 3- to 4-fold increase in activation of the coagulation cascade as shown by increased activated factor X and thrombin production. Culture medium of human embryonic kidney 293 cells over-expressing heparanase and its derivatives increased activated factor X levels in a non-enzymatic manner. When heparanase was added to pooled normal plasma, a 7- to 8-fold increase in activated factor X level was observed. Subsequently, we searched for clinical data supporting this newly identified role of heparanase. Plasma samples from 35 patients with acute leukemia at presentation and 20 healthy donors were studied for heparanase and activated factor X levels. A strong positive correlation was found between plasma heparanase and activated factor X levels (r=0.735, P=0.001). Unfractionated heparin and an inhibitor of activated factor X abolished the effect of heparanase, while tissue factor pathway inhibitor and tissue factor pathway inhibitor-2 only attenuated the procoagulant effect. Using co-immunoprecipitation and far-western analyses it was shown that heparanase interacts directly with tissue factor. Overall, our results support the notion that heparanase is a potential modulator of blood hemostasis, and suggest a novel mechanism by which heparanase increases the generation of activated

Intratumoral distribution of CU-ATSM and FDG: immunohistochemical characterization of the region with high CU-ATSM or FDG accumulation

Energy Technology Data Exchange (ETDEWEB)

Takako, Furukawa; Tsuneo, Saga; Yasuhisa, Fujibayashi [Institute of Radiological Sciences, Dept. of Diagnostic Imaging, Molecular Imaging Center, Nationa, Chiba (Japan); Takako, Furukawa; Takeshi, Tanaka; Yasuhisa, Fujibayashi [Fukui Univ., Biomedica Imaging Research Center (Japan)

2006-07-01

Intratumoral distribution of [Cu-64]Cu-di-acetyl-bis (N4-methyl-thio-semi-carbazone ) ({sup 64}Cu-ATSM) and fluorine-18 2-fluoro-2-deoxyglucose ({sup 18}FDG) in mice bearing tumors of four different origins, LLC1 (Lewis lung carcinoma), Meth-A (sarcoma), B16 (melanoma) and colon26 (adenocarcinoma), were compared to the immunohistochemical staining for proliferating cells (Ki67), blood vessels (CD34 or von Willebrand Factor (vWF)) and apoptotic cells (terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) method). With all the cell lines, {sup 64}Cu-ATSM and {sup 18}FDG were distributed to different regions of the tumor mass. The immunohistochemical study demonstrated that the high {sup 64}Cu-ASTM uptake regions were hypo-vascular and consisted of tumor cells arrested in cell cycle, while the high {sup 18}FGD uptake regions were hyper-vascular and consisted of proliferating cells. Through our study, it was revealed that one tumor mass contains two regions of different characteristics, which can be distinguished by {sup 64}Cu-ATSM and {sup 18}FDG. Since hypoxia and cell cycle arrest are critical factors to reduce the sensitivity of tumor to radiation and conventional chemotherapy, regions with such characteristics in tumor should be treated intensively as one of the primary targets. {sup 64}Cu-ATSM which can delineate hypoxic and cell cycle arrested regions in tumors can provide valuable information for cancer treatment as well as the possibility to treat such regions directly as an internal radiotherapy reagent. (author)

Association of Type D personality with increased vulnerability to depression: Is there a role for inflammation or endothelial dysfunction? - The Maastricht Study.

Science.gov (United States)

van Dooren, Fleur E P; Verhey, Frans R J; Pouwer, Frans; Schalkwijk, Casper G; Sep, Simone J S; Stehouwer, Coen D A; Henry, Ronald M A; Dagnelie, Pieter C; Schaper, Nicolaas C; van der Kallen, Carla J H; Koster, Annemarie; Schram, Miranda T; Denollet, Johan

2016-01-01

Type D personality - the combination of negative affectivity (NA) and social inhibition (SI) - has been associated with depression but little is known about underlying mechanisms. We examined whether (1) Type D is a vulnerability factor for depression in general, (2) Type D is associated with inflammation or endothelial dysfunction, and (3) these biomarkers alter the possible association between Type D and depression. In the Maastricht Study, 712 subjects underwent assessment of NA, SI and Type D personality (DS14), depressive disorder (Mini-International Neuropsychiatric Interview) and depressive symptoms (Patient Health Questionnaire-9). Plasma biomarkers of inflammation (hsCRP, SAA, sICAM-1, IL-6, IL-8, TNF-α) and endothelial dysfunction (sVCAM-1, sICAM-1, E-selectin, vWF) were measured with sandwich immunoassays or ELISA and combined into standardized sumscores. Regarding personality, 49% of the study population was low in NA and SI, 22% had SI only, 12% NA only and 17% had Type D. Depressive disorder and depressive symptoms were significantly more prevalent in Type D versus the other three personality subgroups. Multivariable regression analyses showed that Type D was associated with inflammation (β=0.228, p=0.014) and endothelial dysfunction (β=0.216, p=0.022). After adjustment for these biomarkers, Type D remained independently associated with increased vulnerability to depressive disorder (OR=13.20, ppersonality may be a vulnerability factor for depression, irrespective of levels of inflammation or endothelial dysfunction. Future research should examine possible underlying mechanisms. Copyright © 2015 Elsevier B.V. All rights reserved.

Transforming growth factor alpha, Shope fibroma growth factor, and vaccinia growth factor can replace myxoma growth factor in the induction of myxomatosis in rabbits.

Science.gov (United States)

Opgenorth, A; Nation, N; Graham, K; McFadden, G

1993-02-01

The epidermal growth factor (EGF) homologues encoded by vaccinia virus, myxoma virus, and malignant rabbit fibroma virus have been shown to contribute to the pathogenicity of virus infection upon inoculation of susceptible hosts. However, since the primary structures of these growth factors and the disease profiles induced by different poxvirus genera vary substantially, the degree to which the various EGF homologues perform similar roles in viral pathogenesis remains unclear. In order to determine whether different EGF-like growth factors can perform qualitatively similar functions in the induction of myxomatosis in rabbits, we created recombinant myxoma virus variants in which the native growth factor, myxoma growth factor (MGF), was disrupted and replaced with either vaccinia virus growth factor, Shope fibroma growth factor, or rat transforming growth factor alpha. Unlike the control virus containing an inactivated MGF gene, which caused marked attenuation of the disease syndrome and substantially less proliferation of the epithelial cell layers in the conjunctiva and respiratory tract, the recombinant myxoma virus strains expressing heterologous growth factors produced infections which were both clinically and histopathologically indistinguishable from wild-type myxomatosis. We conclude that these poxviral and cellular EGF-like growth factors, which are diverse with respect to primary structure and origin, have similar biological functions in the context of myxoma virus pathogenesis and are mitogenic for the same target cells.

Factor concentrates for the treatment of factor XIII deficiency.

Science.gov (United States)

Gootenberg, J E

1998-11-01

Factor XIII deficiency is a severe autosomal recessive bleeding disorder associated with a characteristic pattern of neonatal hemorrhage and a lifelong bleeding diathesis. Even relatively minor trauma can be followed by prolonged and recurrent bleeding. Intracranial hemorrhage is a frequent complication. With the development of safe and effective factor XIII concentrates, reliable prophylactic treatment is possible. Two plasma-derived, virus-inactivated factor XIII concentrates are currently in production. The first, Fibrogammin P, (Centeon LLC, King of Prussia, PA, USA; and Centeon Pharma GmbH, Marburg, Germany) is marketed in Europe, South America, South Africa, and Japan. It is distributed in the United States under a Food and Drug Administration Investigational New Drug Application. A second factor XIII concentrate (Bio Products Laboratory, Elstree, UK) is available for use only on a "named patient" compassionate basis in the United Kingdom. Patients with factor XIII deficiency who receive appropriately timed periodic infusions of such factor XIII concentrates are able to live normal lives, free from catastrophic bleeding episodes.

Epidermal growth factor and insulin-like growth factor I upregulate the expression of the epidermal growth factor system in rat liver

DEFF Research Database (Denmark)

Bor, M V; Sørensen, B S; Vinter-Jensen, L

2000-01-01

BACKGROUND/AIM: Both epidermal growth factor and insulin-like growth factor I play a role in connection with the liver. In the present study, the possible interaction of these two growth factor systems was studied by investigating the effect of epidermal growth factor or insulin-like growth factor...... I treatment on the expression of the epidermal growth factor receptor, and its activating ligands, transforming growth factor-alpha and epidermal growth factor. METHODS: Fifty-five male rats received no treatment, human recombinant epidermal growth factor or human recombinant insulin-like growth.......8+/-1.6 fmol/mg protein epidermal growth factor and 144+/-22 fmol/mg protein transforming growth factor-alpha. Both epidermal growth factor and insulin-like growth factor I treatment increased the expression of mRNA for transforming growth factor-alpha and epidermal growth factor receptor, as well...

Hemophilia B with mutations at glycine-48 of factor IX exhibited delayed activation by the factor VIIa-tissue factor complex.

Science.gov (United States)

Wu, P C; Hamaguchi, N; Yu, Y S; Shen, M C; Lin, S W

2000-10-01

Gly-48 is in the conserved DGDQC sequence (residues 47-51 of human factor IX) of the first EGF (EGF-1)-like domain of factor IX. The importance of the Gly-48 is manifested by two hemophilia B patients; factor IXTainan and factor IXMalmo27, with Gly-48 replaced by arginine (designated IXG48R) and valine (IXG48V), respectively. Both patients were CRM+ exhibiting mild hemophilic episodes with 25% (former) and 19% (latter) normal clotting activities. We characterize both factor IX variants to show the roles of Gly-48 and the conservation of the DGDQC sequence in factor IX. Purified plasma and recombinant factor IX variants exhibited approximately 26%-27% normal factor IX's clotting activities with G48R or G48V mutation. Both variants depicted normal quenching of the intrinsic fluorescence by increasing concentrations of calcium ions and Tb3+, indicating that arginine and valine substitution for Gly-48 did not perturb the calcium site in the EGF-1 domain. Activation of both mutants by factor XIa appeared normal. The reduced clotting activity of factors IXG48R and IXG48V was attributed to the failure of both mutants to cleavage factor X: in the presence of only phospholipids and calcium ions, both mutants showed a 4 to approximately 7-fold elevation in Km, and by adding factor VIIIa to the system, although factor VIIIa potentiated the activation of factor X by the mutants factor IXaG48R and factor IXaG48V, a 2 to approximately 3-fold decrease in the catalytic function was observed with the mutant factor IXa's, despite that they bound factor VIIIa on the phospholipid vesicles with only slightly reduced affinity when compared to wild-type factor IXa. The apparent Kd for factor VIIIa binding was 0.83 nM for normal factor IXa, 1.74 nM for IXaG48R and 1.4 nM for IXaG48V. Strikingly, when interaction with the factor VIIa-TF complex was examined, both mutations were barely activated by the VIIa-TF complex and they also showed abnormal interaction with VIIa-TF in bovine

The importance of residues 195-206 of human blood clotting factor VII in the interaction of factor VII with tissue factor

International Nuclear Information System (INIS)

Wildgoose, P.; Kisiel, W.; Kazim, A.L.

1990-01-01

Previous studies indicated that human and bovine factor VII exhibit 71% amino acid sequence identity. In the present study, competition binding experiments revealed that the interaction of human factor VII with cell-surface human tissue factor was not inhibited by 100-fold molar excess of bovine factor VII. This finding indicated that bovine and human factor VII are not structurally homologous in the region(s) where human factor VII interacts with human tissue factor. On this premise, the authors synthesized three peptides corresponding to regions of human factor VII that exhibited marked structural dissimilarity to bovine factor VII; these regions of dissimilarity included residues 195-206, 263-274, and 314-326. Peptide 195-206 inhibited the interaction of factor VII with cell-surface tissue factor and the activation of factor X by a complex of factor VIIa and tissue factor half-maximally at concentrations of 1-2 mM. A structurally rearranged form of peptide 195-206 containing an aspartimide residue inhibited these reactions half-maximally at concentrations of 250-300 μM. In contrast, neither peptide 263-274 nor peptide 314-326, at 2 mM concentration, significantly affected either factor VIIa interaction with tissue factor or factor VIIa-mediated activation of factor X. The data provide presumptive evidence that residues 195-206 of human factor VII are involved in the interaction of human factor VII with the extracellular domain of human tissue factor apoprotein

[Coagulation factor VII levels in uremic patients and theirs influence factors].

Science.gov (United States)

Fang, Jun; Xia, Ling-Hui; Wei, Wen-Ning; Song, Shan-Jun

2004-12-01

This study was aimed to investigate coagulation factor VII level in uremic patients with chronic renal failure and to explore theirs influence factors. The plasma levels of coagulation factor VII were detected in 30 uremic patients with chronic renal failure before and after hemodialysis for 1 month, the factor VII activity (FVII:C) was determined by one-stage coagulation method, while activated factor VII (FVIIa) was measured by one-stage coagulation method using recombinant soluble tissue factor, and factor VII antigen was detected by ELISA. The results showed that: (1) The FVIIa, FVII:C and FVIIAg levels in chronic uremic patients before hemodialysis were 4.00 +/- 0.86 microg/L, (148.5 +/- 40.4)% and (99.8 +/- 21.1)% respectively, which were significantly increased, as compared with healthy controls [2.77 +/- 1.02 microg/L, (113.1 +/- 33.0)% and (73.7 +/- 18.3)% respectively, P factor VII was positively correlated with levels of blood uria nitrogen and serum creatinine before hemodialysis but not after hemodialysis. It is concluded that the enhanced levels of coagulation factor VII in chronic uremic patients suggested abnormal activated state, herperactivity and elevated production of factor VII which correlated with renal functional injury. The abnormality of factor VII in uremia may be aggravated by hemodialysis. Coagulation factor (FVII) may be a risk factor for cardiovascular events in uremic patients who especially had been accepted long-term hemodialysis.

Efficacy and safety of rVIII-SingleChain: results of a phase 1/3 multicenter clinical trial in severe hemophilia A

Science.gov (United States)

Mahlangu, Johnny; Kuliczkowski, Kazimierz; Karim, Faraizah Abdul; Stasyshyn, Oleksandra; Kosinova, Marina V.; Lepatan, Lynda Mae; Skotnicki, Aleksander; Boggio, Lisa N.; Klamroth, Robert; Oldenburg, Johannes; Hellmann, Andrzej; Santagostino, Elena; Baker, Ross I.; Fischer, Kathelijn; Gill, Joan C.; P’Ng, Stephanie; Chowdary, Pratima; Escobar, Miguel A.; Khayat, Claudia Djambas; Rusen, Luminita; Bensen-Kennedy, Debra; Blackman, Nicole; Limsakun, Tharin; Veldman, Alex; St. Ledger, Katie

2016-01-01

Recombinant VIII (rVIII)-SingleChain is a novel B-domain–truncated recombinant factor VIII (rFVIII), comprised of covalently bonded factor VIII (FVIII) heavy and light chains. It was designed to have a higher binding affinity for von Willebrand factor (VWF). This phase 1/3 study investigated the efficacy and safety of rVIII-SingleChain in the treatment of bleeding episodes, routine prophylaxis, and surgical prophylaxis. Participants were ≥12 years of age, with severe hemophilia A (endogenous FVIII <1%). The participants were allocated by the investigator to receive rVIII-SingleChain in either an on-demand or prophylaxis regimen. Of the 175 patients meeting study eligibility criteria, 173 were treated with rVIII-SingleChain, prophylactically (N = 146) or on-demand (N = 27). The total cumulative exposure was 14 306 exposure days (EDs), with 120 participants reaching ≥50 EDs and 52 participants having ≥100 EDs. Hemostatic efficacy was rated by the investigator as excellent or good in 93.8% of the 835 bleeds treated and assessed. Across all prophylaxis regimens, the median annualized spontaneous bleeding rate was 0.00 (Q1, Q3: 0.0, 2.4) and the median overall annualized bleeding rate (ABR) was 1.14 (Q1, Q3: 0.0, 4.2). Surgical hemostasis was rated as excellent/good in 100% of major surgeries by the investigator. No participant developed FVIII inhibitors. In conclusion, rVIII-SingleChain is a novel rFVIII molecule showing excellent hemostatic efficacy in surgery and in the control of bleeding events, low ABR in patients on prophylaxis, and a favorable safety profile in this large clinical study. This trial was registered at www.clinicaltrials.gov as #NCT01486927. PMID:27330001

Cyr61/CCN1 displays high-affinity binding to the somatomedin B(1-44 domain of vitronectin.

Directory of Open Access Journals (Sweden)

Ivo M B Francischetti

2010-02-01

Full Text Available Cyr61 is a member of the CCN (Cyr61, connective tissue growth, NOV family of extracellular-associated (matricellular proteins that present four distinct functional modules, namely insulin-like growth factor binding protein (IGFBP, von Willebrand factor type C (vWF, thrombospondin type 1 (TSP, and C-terminal growth factor cysteine knot (CT domain. While heparin sulphate proteoglycans reportedly mediate the interaction of Cyr61 with the matrix and cell surface, the role of other extracellular associated proteins has not been revealed.In this report, surface plasmon resonance (SPR experiments and solid-phase binding assays demonstrate that recombinant Cyr61 interacts with immobilized monomeric or multimeric vitronectin (VTNC with K(D in the nanomolar range. Notably, the binding site for Cyr61 was identified as the somatomedin B domain (SMTB(1-44 of VTNC, which mediates its interaction with PAI-1, uPAR, and integrin alphav beta3. Accordingly, PAI-1 outcompetes Cyr61 for binding to immobilized SMTB(1-44, and Cyr61 attenuates uPAR-mediated U937 adhesion to VTNC. In contrast, isothermal titration calorimetry shows that Cyr61 does not display high-affinity binding for SMTB(1-44 in solution. Nevertheless, competitive ELISA revealed that multimeric VTNC, heat-modified monomeric VTNC, or SMTB(1-44 at high concentrations attenuate Cyr61 binding to immobilized VTNC, while monomeric VTNC was ineffective. Therefore, immobilization of VTNC exposes cryptic epitopes that recognize Cyr61 with high affinity, as reported for a number of antibodies, beta-endorphin, and other molecules.The finding that Cyr61 interacts with the SMTB(1-44 domain suggests that VTNC represent a point of anchorage for CCN family members to the matrix. Results are discussed in the context of the role of CCN and VTNC in matrix biology and angiogenesis.

External Factors, Internal Factors and Self-Directed Learning Readiness

Science.gov (United States)

Ramli, Nurjannah; Muljono, Pudji; Afendi, Farit M.

2018-01-01

There are many factors which affect the level of self-directed learning readiness. This study aims to investigate the relationship between external factors, internal factors and self-directed learning readiness. This study was carried out by using a census method for fourth year students of medical program of Tadulako University. Data were…

Technology CAD for germanium CMOS circuit

Energy Technology Data Exchange (ETDEWEB)

Saha, A.R. [Department of Electronics and ECE, IIT Kharagpur, Kharagpur-721302 (India)]. E-mail: ars.iitkgp@gmail.com; Maiti, C.K. [Department of Electronics and ECE, IIT Kharagpur, Kharagpur-721302 (India)

2006-12-15

Process simulation for germanium MOSFETs (Ge-MOSFETs) has been performed in 2D SILVACO virtual wafer fabrication (VWF) suite towards the technology CAD for Ge-CMOS process development. Material parameters and mobility models for Germanium were incorporated in simulation via C-interpreter function. We also report on the device design issues along with the DC and RF characterization of the bulk Ge-MOSFETs, AC parameter extraction and circuit simulation of Ge-CMOS. Simulation results are compared with bulk-Si devices. Simulations predict a cut-off frequency, f {sub T} of about 175 GHz for Ge-MOSFETs compared to 70 GHz for a similar gate-length Si MOSFET. For a single stage Ge-CMOS inverter circuit, a GATE delay of 0.6 ns is predicted.

Technology CAD for germanium CMOS circuit

International Nuclear Information System (INIS)

Saha, A.R.; Maiti, C.K.

2006-01-01

Process simulation for germanium MOSFETs (Ge-MOSFETs) has been performed in 2D SILVACO virtual wafer fabrication (VWF) suite towards the technology CAD for Ge-CMOS process development. Material parameters and mobility models for Germanium were incorporated in simulation via C-interpreter function. We also report on the device design issues along with the DC and RF characterization of the bulk Ge-MOSFETs, AC parameter extraction and circuit simulation of Ge-CMOS. Simulation results are compared with bulk-Si devices. Simulations predict a cut-off frequency, f T of about 175 GHz for Ge-MOSFETs compared to 70 GHz for a similar gate-length Si MOSFET. For a single stage Ge-CMOS inverter circuit, a GATE delay of 0.6 ns is predicted

A factor analysis to detect factors influencing building national brand

Directory of Open Access Journals (Sweden)

Naser Azad

Full Text Available Developing a national brand is one of the most important issues for development of a brand. In this study, we present factor analysis to detect the most important factors in building a national brand. The proposed study uses factor analysis to extract the most influencing factors and the sample size has been chosen from two major auto makers in Iran called Iran Khodro and Saipa. The questionnaire was designed in Likert scale and distributed among 235 experts. Cronbach alpha is calculated as 84%, which is well above the minimum desirable limit of 0.70. The implementation of factor analysis provides six factors including “cultural image of customers”, “exciting characteristics”, “competitive pricing strategies”, “perception image” and “previous perceptions”.

A systematic overview of the first pasteurised VWF/FVIII medicinal product, Haemate P/ Humate -P: history and clinical performance

DEFF Research Database (Denmark)

Berntorp, E.; Archey, W.; Auerswald, G.

2008-01-01

of thromboembolic complications does exist while receiving Haemate P, as it does with any FVIII replacement therapy, the incidence of such complications has remained notably low. Given the robust data that have accumulated for the use of Haemate P, dosing recommendations are also described in this review...

Scoring functions for protein-protein interactions.

Science.gov (United States)

Moal, Iain H; Moretti, Rocco; Baker, David; Fernández-Recio, Juan

2013-12-01

The computational evaluation of protein-protein interactions will play an important role in organising the wealth of data being generated by high-throughput initiatives. Here we discuss future applications, report recent developments and identify areas requiring further investigation. Many functions have been developed to quantify the structural and energetic properties of interacting proteins, finding use in interrelated challenges revolving around the relationship between sequence, structure and binding free energy. These include loop modelling, side-chain refinement, docking, multimer assembly, affinity prediction, affinity change upon mutation, hotspots location and interface design. Information derived from models optimised for one of these challenges can be used to benefit the others, and can be unified within the theoretical frameworks of multi-task learning and Pareto-optimal multi-objective learning. Copyright © 2013 Elsevier Ltd. All rights reserved.

Evaluación del interés sexual hacia menores

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Óscar Herrero

2016-01-01

Full Text Available El interés sexual hacia menores ofrece numerosas dificultades para su evaluación, principalmente, la motivación para ocultarlo en contextos forenses. Su asociación con la reincidencia en delitos sexuales y su utilidad como medida del éxito terapéutico han impulsado el desarrollo de distintas técnicas de evaluación. En este artículo se revisan los autoinformes, la pletismografía peneana y varias medidas cognitivas basadas en la latencia de respuesta. Aunque todas las técnicas presentan limitaciones en cuanto a su manipulación y a su capacidad discriminativa, las baterías multimétodo parecen ofrecer la mejor alternativa y son una vía de investigación futura.

Characteristics of tau oligomers

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Yan eRen

2013-07-01

Full Text Available In Alzheimer disease (AD and other tauopathies, microtubule-associated protein tau becomes hyperphosphorylated, undergoes conformational changes, aggregates, eventually becoming neurofibrillary tangles (NFTs. As accumulating evidence suggests that NFTs themselves may not be toxic, attention is now turning toward the role of intermediate tau oligomers in AD pathophysiology. Sarkosyl extraction is a standard protocol for investigating insoluble tau aggregates in brains. There is a growing consensus that sarkosyl-insoluble tau correlates with the pathological features of tauopathy. While sarkosyl-insoluble tau from tauopathy brains has been well characterized as a pool of filamentous tau, other dimers, multimers, and granules of tau are much less well understood. There are protocols for identifying these tau oligomers. In this mini review, we discuss the characteristics of tau oligomers isolated via different methods and materials.

T cell recognition of breast cancer antigens

DEFF Research Database (Denmark)

Petersen, Nadia Viborg; Andersen, Sofie Ramskov; Andersen, Rikke Sick

Recent studies are encouraging research of breast cancer immunogenicity to evaluate the applicability ofimmunotherapy as a treatment strategy. The epitope landscape in breast cancer is minimally described, thus it is necessary to identify T cell targets to develop immune mediated therapies.......This project investigates four proteins commonly upregulated in breast cancer and thus probable tumor associated antigens (TAAs). Aromatase, prolactin, NEK3, and PIAS3 contribute to increase growth, survival, and motility of malignant cells. Aspiring to uncover novel epitopes for cytotoxic T cells, a reverse...... recognition utilizing DNA barcode labeled MHC multimers to screen peripheral blood lymphocytes from breast cancer patients and healthy donor samples. Signif-icantly more TAA specific T cell responses were detected in breast cancer patients than healthy donors for both HLA-A*0201 (P

Intégration des données multimédias dans les Systèmes d ...

African Journals Online (AJOL)

Integration of multimedia data in to Geographic Information Systems The needs in new Geographic Information System (GIS) applications are growing. The multimedia applications suggests the integration and the managment of text, image, sound and video . Temporal dependencies are the characteristics of multimedia ...

Folding Landscape of Mutant Huntingtin Exon1: Diffusible Multimers, Oligomers and Fibrils, and No Detectable Monomer.

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Bankanidhi Sahoo

Full Text Available Expansion of the polyglutamine (polyQ track of the Huntingtin (HTT protein above 36 is associated with a sharply enhanced risk of Huntington's disease (HD. Although there is general agreement that HTT toxicity resides primarily in N-terminal fragments such as the HTT exon1 protein, there is no consensus on the nature of the physical states of HTT exon1 that are induced by polyQ expansion, nor on which of these states might be responsible for toxicity. One hypothesis is that polyQ expansion induces an alternative, toxic conformation in the HTT exon1 monomer. Alternative hypotheses posit that the toxic species is one of several possible aggregated states. Defining the nature of the toxic species is particularly challenging because of facile interconversion between physical states as well as challenges to identifying these states, especially in vivo. Here we describe the use of fluorescence correlation spectroscopy (FCS to characterize the detailed time and repeat length dependent self-association of HTT exon1-like fragments both with chemically synthesized peptides in vitro and with cell-produced proteins in extracts and in living cells. We find that, in vitro, mutant HTT exon1 peptides engage in polyQ repeat length dependent dimer and tetramer formation, followed by time dependent formation of diffusible spherical and fibrillar oligomers and finally by larger, sedimentable amyloid fibrils. For expanded polyQ HTT exon1 expressed in PC12 cells, monomers are absent, with tetramers being the smallest molecular form detected, followed in the incubation time course by small, diffusible aggregates at 6-9 hours and larger, sedimentable aggregates that begin to build up at 12 hrs. In these cell cultures, significant nuclear DNA damage appears by 6 hours, followed at later times by caspase 3 induction, mitochondrial dysfunction, and cell death. Our data thus defines limits on the sizes and concentrations of different physical states of HTT exon1 along the reaction profile in the context of emerging cellular distress. The data provide some new candidates for the toxic species and some new reservations about more well-established candidates. Compared to other known markers of HTT toxicity, nuclear DNA damage appears to be a relatively early pathological event.

Literatura e interseção dos campos artísticos na cultura multimídia

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Vera Lúcia Follain Figueiredo

2015-12-01

Full Text Available This work parts from the growing intersection between artistic fields, driven not only by technological advances, but also by the cultural market interests, to think the changes in writing and reading experiences in multimediatic society. We discuss creative projects that have in common the fact that expand the boundaries of literature beyond the book support and prioritize the texts displacements, recycling processes, to the detriment of originality and individual creation.

Desafios da radiodifusão sonora na convergência multimídia: o segmento musical jovem

OpenAIRE

Luiz Artur Ferraretto; UCS/RS

2008-01-01

Este texto faz uma reflexão sobre as origens, o desenvolvimento e as perspectivas do segmento musical jovem nas emissoras de rádio. Parte do papel histórico do veículo na constituição, de início, da categoria social representada pela juventude e, na seqüência, no tratamento desse como público consumidor. Chega-se, assim, ao momento atual, um cenário de multiplicidade de ofertas marcada pela presença da internet e...

Elaboració i desenvolupament d'un llibre multimèdia sobre programació matemàtica

Directory of Open Access Journals (Sweden)

Begoña Font Belaire

2008-12-01

Full Text Available The edition of handbooks adapted to the self-learning paradigm and using the advantages of the information and communication  technologies (ICT is basic in the educational innovation processes’ success that the Spanish university is involved. This article describes the characteristics that a good electronic book should have. It proposes a methodology for the development of electronic books, shows that this method can be successfully implemented, and presents an example of that: the e-book titled Programación matemática para la economíay la empresa.

Low temperatures reduce skin healing in the Jacaré do Pantanal (Caiman yacare, Daudin 1802

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Leandro Nogueira Pressinotti

2013-09-01

Studies of skin wound healing in crocodilians are necessary given the frequent occurrence of cannibalism in intensive farming systems. Air temperature affects tissue recovery because crocodilians are ectothermic. Therefore, the kinetics of skin wound healing in Caiman yacare were examined at temperatures of 33°C and 23°C. Sixteen caiman were selected and divided into two groups of eight maintained at 23°C or 33°C. The studied individuals' scars were photographed after 1, 2, 3, 7, 15 and 30 days of the experimental conditions, and samples were collected for histological processing after 3, 7, 15 and 30 days. Macroscopically, the blood clot (heterophilic granuloma noticeably remained in place covering the wound longer for the caiman kept at 23°C. Microscopically, the temperature of 23°C slowed epidermal migration and skin repair. Comparatively, new blood vessels, labeled using von Willebrand factor (vWF antibody staining, were more frequently found in the scars of the 33°C group. The collagen fibers in the dermis were denser in the 33°C treatment. Considering the delayed healing at 23°C, producers are recommended to keep wounded animals at 33°C, especially when tanks are cold, to enable rapid wound closure and better repair of collagen fibers because such lesions tend to compromise the use of their skin as leather.

Characterization of coding synonymous and non-synonymous variants in ADAMTS13 using ex vivo and in silico approaches.

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Nathan C Edwards

Full Text Available Synonymous variations, which are defined as codon substitutions that do not change the encoded amino acid, were previously thought to have no effect on the properties of the synthesized protein(s. However, mounting evidence shows that these "silent" variations can have a significant impact on protein expression and function and should no longer be considered "silent". Here, the effects of six synonymous and six non-synonymous variations, previously found in the gene of ADAMTS13, the von Willebrand Factor (VWF cleaving hemostatic protease, have been investigated using a variety of approaches. The ADAMTS13 mRNA and protein expression levels, as well as the conformation and activity of the variants have been compared to that of wild-type ADAMTS13. Interestingly, not only the non-synonymous variants but also the synonymous variants have been found to change the protein expression levels, conformation and function. Bioinformatic analysis of ADAMTS13 mRNA structure, amino acid conservation and codon usage allowed us to establish correlations between mRNA stability, RSCU, and intracellular protein expression. This study demonstrates that variants and more specifically, synonymous variants can have a substantial and definite effect on ADAMTS13 function and that bioinformatic analysis may allow development of predictive tools to identify variants that will have significant effects on the encoded protein.

Identifying the important factors in simulation models with many factors

NARCIS (Netherlands)

Bettonvil, B.; Kleijnen, J.P.C.

1994-01-01

Simulation models may have many parameters and input variables (together called factors), while only a few factors are really important (parsimony principle). For such models this paper presents an effective and efficient screening technique to identify and estimate those important factors. The

Quality factors

International Nuclear Information System (INIS)

Kerr, G.D.

1986-01-01

The quality factor, Q, is a dimensionless modifier used in converting absorbed dose, expressed in rads (or grays), to dose equivalent, expressed in rems (or seiverts). The dose equivalent is used in radiation protection to account for the biological effectiveness of different kinds of radiation. The quality factor is related to both the linear energy transfer (LET) and relative biological effectiveness (RBE). The RBE's obtained from biological experiments depend in a complex way on the observed biological effect, the specific test organism, and the experimental conditions. Judgement is involved, therefore, in the choice of the quality factor. Questions regarding the adequacy of current Q values for neutrons were raised first in a 1980 statement by the National Council on Radiation Protection (NCRP) and later in a 1985 statement by the International Commission on Radiological Protection (ICRP). In 1980, the NCRP alerted the technical community to possible future increases between a factor of three and ten in the Q for neutrons, and in 1985, the ICRP suggested an increase by a factor of two in Q for neutrons. Both the ICRP and NRCP are now recommending essentially the same guidance with regard to Q for neutrons: an increase by a factor of two. The Q for neutrons is based on a large, albeit unfocused, body of experimental data. In spite of the lack of focus, the data supporting a change in the neutron quality factor are substantial. However, the proposed doubling of Q for neutrons is clouded by other issues regarding its application. 33 refs., 4 figs., 6 tabs

Kinetics of the Factor XIa catalyzed activation of human blood coagulation Factor IX

International Nuclear Information System (INIS)

Walsh, P.N.; Bradford, H.; Sinha, D.; Piperno, J.R.; Tuszynski, G.P.

1984-01-01

The kinetics of activation of human Factor IX by human Factor XIa was studied by measuring the release of a trichloroacetic acid-soluble tritium-labeled activation peptide from Factor IX. Initial rates of trichloroacetic acid-soluble 3 H-release were linear over 10-30 min of incubation of Factor IX (88 nM) with CaCl 2 (5 mM) and with pure (greater than 98%) Factor XIa (0.06-1.3 nM), which was prepared by incubating human Factor XI with bovine Factor XIIa. Release of 3 H preceded the appearance of Factor IXa activity, and the percentage of 3 H released remained constant when the mole fraction of 3 H-labeled and unlabeled Factor IX was varied and the total Factor IX concentration remained constant. A linear correlation (r greater than 0.98, P less than 0.001) was observed between initial rates of 3 H-release and the concentration of Factor XIa, measured by chromogenic assay and by radioimmunoassay and added at a Factor IX:Factor XIa molar ratio of 70-5,600. Kinetic parameters, determined by Lineweaver-Burk analysis, include K/sub m/ (0.49 microM) of about five- to sixfold higher than the plasma Factor IX concentration, which could therefore regulate the reaction. The catalytic constant (k/sub cat/) (7.7/s) is approximately 20-50 times higher than that reported by Zur and Nemerson for Factor IX activation by Factor VIIa plus tissue factor. Therefore, depending on the relative amounts of Factor XIa and Factor VIIa generated in vivo and other factors which may influence reaction rates, these kinetic parameters provide part of the information required for assessing the relative contributions of the intrinsic and extrinsic pathways to Factor IX activation, and suggest that the Factor XIa catalyzed reaction is physiologically significant

Factoring in Factor VIII With Acute Ischemic Stroke.

Science.gov (United States)

Siegler, James E; Samai, Alyana; Albright, Karen C; Boehme, Amelia K; Martin-Schild, Sheryl

2015-10-01

There is growing research interest into the etiologies of cryptogenic stroke, in particular as it relates to hypercoagulable states. An elevation in serum levels of the procoagulant factor VIII is recognized as one such culprit of occult cerebral infarctions. It is the objective of the present review to summarize the molecular role of factor VIII in thrombogenesis and its clinical use in the diagnosis and prognosis of acute ischemic stroke. We also discuss the utility of screening for serum factor VIII levels among patients at risk for, or those who have experienced, ischemic stroke. © The Author(s) 2015.

Using Bayes factors for multi-factor, biometric authentication

Science.gov (United States)

Giffin, A.; Skufca, J. D.; Lao, P. A.

2015-01-01

Multi-factor/multi-modal authentication systems are becoming the de facto industry standard. Traditional methods typically use rates that are point estimates and lack a good measure of uncertainty. Additionally, multiple factors are typically fused together in an ad hoc manner. To be consistent, as well as to establish and make proper use of uncertainties, we use a Bayesian method that will update our estimates and uncertainties as new information presents itself. Our algorithm compares competing classes (such as genuine vs. imposter) using Bayes Factors (BF). The importance of this approach is that we not only accept or reject one model (class), but compare it to others to make a decision. We show using a Receiver Operating Characteristic (ROC) curve that using BF for determining class will always perform at least as well as the traditional combining of factors, such as a voting algorithm. As the uncertainty decreases, the BF result continues to exceed the traditional methods result.

Electroweak form factors

International Nuclear Information System (INIS)

Singh, S.K.

2002-01-01

The present status of electroweak nucleon form factors and the N - Δ transition form factors is reviewed. Particularly the determination of dipole mass M A in the axial vector form factor is discussed

Evidence that Autophosphorylation of the Major Sporulation Kinase in Bacillus subtilis Is Able To Occur in trans.

Science.gov (United States)

Devi, Seram Nganbiton; Kiehler, Brittany; Haggett, Lindsey; Fujita, Masaya

2015-08-01

. Autophosphorylation of histidine kinases is known to occur by either the cis (one subunit of kinase phosphorylating itself within the multimer) or the trans (one subunit of the multimer phosphorylates the other subunit) mechanism. The present study provided direct in vivo and in vitro evidence that autophosphorylation of the major sporulation histidine kinase (KinA) is able to occur in trans within the homotetramer complex. While the physiological and mechanistic significance of the trans autophosphorylation reaction remains obscure, understanding the detailed reaction mechanism of the sporulation kinase is the first step toward gaining insight into the molecular mechanisms of the initiation of sporulation, which is believed to be triggered by unknown factors produced under conditions of nutrient depletion. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

El factoring

Directory of Open Access Journals (Sweden)

Alberto Rosenthal

1988-04-01

Full Text Available RESUMEN El artículo  presenta, una conceptualización general de lo que es el factoring, el origen del mismo, su evolución y hace una clasificación de los distintos tipos de factoring.

Raynaud′s phenomenon among men and women with noise-induced hearing loss in relation to vibration exposure

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Hans Pettersson

2014-01-01

Full Text Available Raynaud′s phenomenon is characterized by constriction in blood supply to the fingers causing finger blanching, of white fingers (WF and is triggered by cold. Earlier studies found that workers using vibrating hand-held tools and who had vibration-induced white fingers (VWF had an increased risk for hearing loss compared with workers without VWF. This study examined the occurrence of Raynaud′s phenomenon among men and women with noise-induced hearing loss in relation to vibration exposure. All 342 participants had a confirmed noise-induced hearing loss medico legally accepted as work-related by AFA Insurance. Each subject answered a questionnaire concerning their health status and the kinds of exposures they had at the time when their hearing loss was first discovered. The questionnaire covered types of exposures, discomforts in the hands or fingers, diseases and medications affecting the blood circulation, the use of alcohol and tobacco and for women, the use of hormones and whether they had been pregnant. The participation rate was 41% (n = 133 with 38% (n = 94 for men and 50% (n = 39 for women. 84 men and 36 women specified if they had Raynaud′s phenomenon and also if they had used hand-held vibrating machines. Nearly 41% of them had used hand-held vibrating machines and 18% had used vibrating machines at least 2 h each workday. There were 23 men/6 women with Raynaud′s phenomenon. 37% reported WF among those participants who were exposed to hand-arm vibration (HAV and 15% among those not exposed to HAV. Among the participants with hearing loss with daily use of vibrating hand-held tools more than twice as many reports WF compared with participants that did not use vibrating hand-held tools. This could be interpreted as Raynaud′s phenomenon could be associated with an increased risk for noise-induced hearing loss. However, the low participation rate limits the generalization of the results from this study.

Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation.

Science.gov (United States)

Gaviglio, Angela L; Knelson, Erik H; Blobe, Gerard C

2017-05-01

High-risk neuroblastoma is characterized by undifferentiated neuroblasts and low schwannian stroma content. The tumor stroma contributes to the suppression of tumor growth by releasing soluble factors that promote neuroblast differentiation. Here we identify heparin-binding epidermal growth factor-like growth factor (HBEGF) as a potent prodifferentiating factor in neuroblastoma. HBEGF mRNA expression is decreased in human neuroblastoma tumors compared with benign tumors, with loss correlating with decreased survival. HBEGF protein is expressed only in stromal compartments of human neuroblastoma specimens, with tissue from high-stage disease containing very little stroma or HBEGF expression. In 3 human neuroblastoma cell lines (SK-N-AS, SK-N-BE2, and SH-SY5Y), soluble HBEGF is sufficient to promote neuroblast differentiation and decrease proliferation. Heparan sulfate proteoglycans and heparin derivatives further enhance HBEGF-induced differentiation by forming a complex with the epidermal growth factor receptor, leading to activation of the ERK1/2 and STAT3 pathways and up-regulation of the inhibitor of DNA binding transcription factor. These data support a role for loss of HBEGF in the neuroblastoma tumor microenvironment in neuroblastoma pathogenesis.-Gaviglio, A. L., Knelson, E. H., Blobe, G. C. Heparin-binding epidermal growth factor-like growth factor promotes neuroblastoma differentiation. © FASEB.

Tumour Necrosis Factor-alpha and Nuclear Factor-kappa B Gene Variants in Sepsis.

Science.gov (United States)

Acar, Leyla; Atalan, Nazan; Karagedik, E Hande; Ergen, Arzu

2018-01-20

The humoral system is activated and various cytokines are released due to infections in tissues and traumatic damage. Nuclear factor-kappa B dimers are encoded by nuclear factor-kappa B genes and regulate transcription of several crucial proteins of inflammation such as tumour necrosis factor-alpha. To investigate the possible effect of polymorphisms on tumour necrosis factor-alpha serum levels with clinical and prognostic parameters of sepsis by determining the nuclear factor-kappa B-1-94 ins/del ATTG and tumour necrosis factor-alpha (-308 G/A) gene polymorphisms and tumour necrosis factor-alpha serum levels. Case-control study. Seventy-two patients with sepsis and 104 healthy controls were included in the study. In order to determine the polymorphisms of nuclear factor-kappa B-1-94 ins/del ATTG and tumour necrosis factor-alpha (-308 G/A), polymerase chain reaction-restriction fragment length polymorphism analysis was performed and serum tumour necrosis factor-alpha levels were determined using an enzyme-linked immunosorbent assay. We observed no significant differences in tumour necrosis factor-alpha serum levels between the study groups. In the patient group, an increase in the tumour necrosis factor-alpha serum levels in patients carrying the tumour necrosis factor-alpha (-308 G/A) A allele compared to those without the A allele was found to be statistically significant. Additionally, an increase in the tumour necrosis factor-alpha serum levels in patients carrying tumour necrosis factor-alpha (-308 G/A) AA genotype compared with patients carrying the AG or GG genotypes was statistically significant. No significant differences were found in these 2 polymorphisms between the patient and control groups (p>0.05). Our results showed the AA genotype and the A allele of the tumour necrosis factor-alpha (-308 G/A) polymorphism may be used as a predictor of elevated tumour necrosis factor-alpha levels in patients with sepsis.

Influence of process parameters on threshold voltage and leakage current in 18nm NMOS device

Science.gov (United States)

Atan, Norani Binti; Ahmad, Ibrahim Bin; Majlis, Burhanuddin Bin Yeop; Fauzi, Izzati Binti Ahmad

2015-04-01

The process parameters are very crucial factor in the development of transistors. There are many process parameters that influenced in the development of the transistors. In this research, we investigate the effects of the process parameters variation on response characteristics such as threshold voltage (VTH) and sub-threshold leakage current (IOFF) in 18nm NMOS device. The technique to identify semiconductor process parameters whose variability would impact most on the device characteristic is realized through the process by using Taguchi robust design method. This paper presents the process parameters that influenced in threshold voltage (VTH) and sub-threshold leakage current (IOFF) which includes the Halo Implantation, Compensation Implantation, Adjustment Threshold voltage Implantation and Source/Drain Implantation. The design, fabrication and characterization of 18nm HfO2/TiSi2 NMOS device is simulated and performed via a tool called Virtual Wafer Fabrication (VWF) Silvaco TCAD Tool known as ATHENA and ATLAS simulators. These two simulators were combined with Taguchi L9 Orthogonal method to aid in the design and the optimization of the process parameters to achieve the optimum average of threshold voltage (VTH) and sub-threshold leakage current, (IOFF) in 18nm device. Results from this research were obtained; where Halo Implantation dose was identified as one of the process parameter that has the strongest effect on the response characteristics. Whereby the Compensation Implantation dose was identified as an adjustment factor to get the nominal values of threshold voltage VTH, and sub-threshold leakage current, IOFF for 18nm NMOS devices equal to 0.302849 volts and 1.9123×10-16 A/μm respectively. The design values are referred to ITRS 2011 prediction.

Treatment with platelet lysate induces endothelial differentation of bone marrow mesenchymal stem cells under fluid shear stress.

Science.gov (United States)

Homayouni Moghadam, Farshad; Tayebi, Tahereh; Moradi, Alireza; Nadri, Hamid; Barzegar, Kazem; Eslami, Gilda

2014-01-01

By considering stem cell-based therapies as a new hope for the treatment of some tragic diseases, marrow stromal cells or marrow mesenchymal stem cells (MSCs) were considered as a suitable and safe multipotential cell source for this new therapeutic approach. For this purpose, many investigations have been performed on differentiation of MSCs toward specific cell lines to overcome the demand for providing the organ specific cells for cell therapy or preparation of engineered tissues. In the present study, differentiation of MSCs to endothelial cells (ECs) by mechanical and chemical stimulation was evaluated. Fluid shear stress (FSS) was used as mechanical inducer, while platelet lysate (PL) and estradiol (E) were used as chemical induction factors. MSCs were placed under FSS with different forces (2, 5 and 10dyn/cm(2)) for different periods (6, 12 and 24 hours). In some groups, PL and E were added to the culture media to evaluate their effect on expression of EC specific markers. This investigation revealed that FSS with low tension (2.5-5 dyn/cm(2)) for a long time (24 hours) or high tension (10 dyn/cm(2)) in short time (6 hours) in the presence of PL could differentiate MSCs toward ECs. The presence of PL was necessary for initiation of endothelial differentiation, and in the absence of PL, there was not any expression of CD34 and Cadherin5 (Cdh5) among cells. Adding E to the culture medium did not change the rate of endothelial differentiation under FSS. Generated endothelial progenitors could produce von Willebrand factor (vWF) after two weeks culture and also they formed tubular structures after culture on matrigel.

Growth factors II: insuline-like growth binging proteins (GFBPs Factores de crecimiento II: factores insulinoides de crecimiento

Directory of Open Access Journals (Sweden)

Hilda Norha Jaramillo Londoño

1996-03-01

Full Text Available This review summarizes recent knowledge concerning Insulin.like growth factors I and II, with emphasis on their biochemical structure, concentrations, binding proteins, receptors, mechanisms of action, biological effects, and alterations of their concentrations in biological fluids. Se revisan los Factores Insulinoides de Crecimiento, también denominados ";Factores de Crecimiento Similares a la Insulina";, sobre los cuales se dispone de abundante información. Se sintetizan conocimientos recientes sobre dichos factores con énfasis en los siguientes aspectos: estructura bioquímica, concentraciones y sus cambios en los líquidos biológicos, proteínas fijadoras, receptores, mecanismos de acción y efectos biológicos.

EVALUATING THE IMPORTANCE OF FACTORS IN ANY GIVEN ORDER OF FACTORING.

Science.gov (United States)

Humphreys, L G; Tucker, L R; Dachler, P

1970-04-01

A methodology has been described and illustrated for obtaining an evaluation of the importance of the factors in a particular order of factoring that does not require faotoring beyond that order. For example, one can estimate the intercorrelations of the original measures with the perturbations of the first-order factor held constant or, the reverse, estimate the contribution to the intercorrelations of the originral measures from the first-order factors alone. Similar operations are possible at higher orders.

Robust factorization

DEFF Research Database (Denmark)

Aanæs, Henrik; Fisker, Rune; Åström, Kalle

2002-01-01

Factorization algorithms for recovering structure and motion from an image stream have many advantages, but they usually require a set of well-tracked features. Such a set is in generally not available in practical applications. There is thus a need for making factorization algorithms deal effect...

Heart disease - risk factors

Science.gov (United States)

Heart disease - prevention; CVD - risk factors; Cardiovascular disease - risk factors; Coronary artery disease - risk factors; CAD - risk ... a certain health condition. Some risk factors for heart disease you cannot change, but some you can. ...

The joy of factoring

CERN Document Server

Wagstaff, Samuel S

2013-01-01

This book is about the theory and practice of integer factorization presented in a historic perspective. It describes about twenty algorithms for factoring and a dozen other number theory algorithms that support the factoring algorithms. Most algorithms are described both in words and in pseudocode to satisfy both number theorists and computer scientists. Each of the ten chapters begins with a concise summary of its contents. The book starts with a general explanation of why factoring integers is important. The next two chapters present number theory results that are relevant to factoring. Further on there is a chapter discussing, in particular, mechanical and electronic devices for factoring, as well as factoring using quantum physics and DNA molecules. Another chapter applies factoring to breaking certain cryptographic algorithms. Yet another chapter is devoted to practical vs. theoretical aspects of factoring. The book contains more than 100 examples illustrating various algorithms and theorems. It also co...

A factor analysis to find critical success factors in retail brand

Directory of Open Access Journals (Sweden)

Naser Azad

2013-03-01

Full Text Available The present exploratory study aims to find critical components of retail brand among some retail stores. The study seeks to build a brand name in retail level and looks to find important factors affecting it. Customer behavior is largely influenced when the first retail customer experience is formed. These factors have direct impacts on customer experience and satisfaction in retail industry. The proposed study performs an empirical investigation on two well-known retain stores located in city of Tehran, Iran. Using a sample of 265 people from regular customers, the study uses factor analysis and extracts four main factors including related brand, product benefits, customer welfare strategy and corporate profits using the existing 31 factors in the literature.

Theoretical difference between impact factor and influence factor

Directory of Open Access Journals (Sweden)

Đilda Pečarić

2010-06-01

Full Text Available Bibliometric constructions of "knowledge maps" and "cognitive structures of science" do not differentiate between impact and influence factors. The difference can be constructedaccording to different meaning and interpretation of the terms reference and citation. Reference is "acknowledgment which one author gives to another", whereas citation is "acknowledgment which one document receives from another". Development of Information Science according to period and subject area is analyzed on the corpus of citation literature retrieved from doctoral dissertations in Information Science from 1978 to 2007 at Croatian universities. The research aim is to indicate the difference between document impact factor and author's influence factor (i.e. reference ability to produce effects on actions, behavior, and opinions of authors of doctoral theses. The influence factor serves to distinguish the key role of cited authors in time and according to the duration of the influence (the average age for cited papers of dominant authors in different periods is between eight and ten years. The difference between linear and interactive communication seems vital for the interpretation of cited half-life, i.e. the attitude of one science community towards used information resources and cognitive heritage. The analyzed corpus of 22,210 citations can be divided into three communication phases according to influence factor criteria: in the phase of dialogue and interactive communication 25% of bibliographic units are cited in the first four years; in the second phase another 25% of units are cited from the fifth to the ninth year; after ten years, in the dominant linear communication phase, approximately 30% of units are cited.

Amplification factor variable amplifier

NARCIS (Netherlands)

Akitsugu, Oshita; Nauta, Bram

2007-01-01

PROBLEM TO BE SOLVED: To provide an amplification factor variable amplifier capable of achieving temperature compensation of an amplification factor over a wide variable amplification factor range. ; SOLUTION: A Gilbert type amplification factor variable amplifier 11 amplifies an input signal and

Electrical tortuosity, Kozeny’s factor and cementation factor modelled for chalk

DEFF Research Database (Denmark)

Katika, Konstantina; Fabricius, Ida Lykke

2015-01-01

saturated core plugs to determine the cementation factor, m. This value differs from the one Archie used to describe his equation and best describes the formation factor based on experimental data. Based on this m, we determine the formation factor, F, and the tortuosity, τ. We use this value of τ...

Gynaecological and obstetric management of women with inherited bleeding disorders.

Science.gov (United States)

Demers, Christine; Derzko, Christine; David, Michèle; Douglas, Joanne

2006-10-01

The prevalence of bleeding disorders, notably von Willebrand disease (vWD), among adult women with objectively documented menorrhagia is consistently reported to be 10% to 20% and is even higher in adolescents presenting with menorrhagia. This consensus document has been developed by a multidisciplinary committee consisting of an anesthesiologist, 2 hematologists, and an obstetrician/gynaecologist and has been endorsed by their relevant specialty bodies. It has been prepared with the express purpose of providing guidelines for both women with inherited bleeding disorders and for their caregivers regarding the gynaecological and obstetric management of these women, including appropriate anesthesia support where indicated. Diagnostic tools and specific medical and, where appropriate, surgical alternatives to management are reviewed and evidence-based recommendations presented. A MEDLINE search of the English literature between January 1975 and November 2003 was performed using the following key words: menorrhagia, uterine bleeding, pregnancy, von Willebrand, congenital bleeding disorder, desmopressin/DDAVP, tranexamic acid, oral contraceptives, medroxyprogesterone, therapy, hysterectomy, anesthesia, epidural, spinal. Recommendations from other society guidelines were reviewed. 1. Inherited bleeding disorders should be considered in the differential diagnosis of all patients presenting with menorrhagia (II-2B). The graphical scoring system presented is a validated tool which offers a simple yet practical method that can be used by patients to quantify their blood loss (II-2B). 2. Because underlying bleeding disorders are frequent in women with menorrhagia, physicians should consider performing a hemoglobin/hematocrit, platelet count, ferritin, PT (INR) and APTT in women with menorrhagia. In women who have a personal history of other bleeding or a family history of bleeding, further investigation should be considered, including a vWD workup (factor VIII, vWF antigen

Amplification factor variable amplifier

NARCIS (Netherlands)

Akitsugu, Oshita; Nauta, Bram

2010-01-01

PROBLEM TO BE SOLVED: To provide an amplification factor variable amplifier capable of achieving temperature compensation of an amplification factor over a wide variable amplification factor range. ;SOLUTION: A Gilbert type amplification factor variable amplifier 11 amplifies an input signal and can

Risk Factors for Internet Gaming Disorder: Psychological Factors and Internet Gaming Characteristics.

Science.gov (United States)

Rho, Mi Jung; Lee, Hyeseon; Lee, Taek-Ho; Cho, Hyun; Jung, Dong Jin; Kim, Dai-Jin; Choi, In Young

2017-12-27

Background : Understanding the risk factors associated with Internet gaming disorder (IGD) is important to predict and diagnose the condition. The purpose of this study is to identify risk factors that predict IGD based on psychological factors and Internet gaming characteristics; Methods : Online surveys were conducted between 26 November and 26 December 2014. There were 3568 Korean Internet game users among a total of 5003 respondents. We identified 481 IGD gamers and 3087 normal Internet gamers, based on Diagnostic and Statistical Manual for Mental Disorders (DSM-5) criteria. Logistic regression analysis was applied to identify significant risk factors for IGD; Results : The following eight risk factors were found to be significantly associated with IGD: functional and dysfunctional impulsivity (odds ratio: 1.138), belief self-control (1.034), anxiety (1.086), pursuit of desired appetitive goals (1.105), money spent on gaming (1.005), weekday game time (1.081), offline community meeting attendance (2.060), and game community membership (1.393; p < 0.05 for all eight risk factors); Conclusions : These risk factors allow for the prediction and diagnosis of IGD. In the future, these risk factors could also be used to inform clinical services for IGD diagnosis and treatment.

Synergistic effect of factor VII gene polymorphisms causing mild factor VII deficiency in a case of severe factor X deficiency.

Science.gov (United States)

Deshpande, Rutuja; Ghosh, Kanjaksha; Shetty, Shrimati

2017-01-01

Congenital combined deficiency of coagulation factors VII and X are mainly attributed to large deletions involving both the genes in chromosome 13 or occasionally due to the coincidental occurrence of independently occurring mutations. We report the molecular basis of congenital combined deficiency of factors VII and X in a 6-year-old female child. Direct DNA sequencing of both factor VII (F7) and factor X (F10) genes showed a novel homozygous missense mutation p.Cys90Tyr (c.307G>A) in exon 4 of F10. No mutations were detected in F7; however, the patient was homozygous for three polymorphic alleles known to be associated with reduced factor VII levels. The present case illustrates the synergistic effect of multiple polymorphisms resulting in phenotypic factor VII deficiency in the absence of a pathogenic mutation.

Mesonic Form Factors

Energy Technology Data Exchange (ETDEWEB)

Frederic D. R. Bonnet; Robert G. Edwards; George T. Fleming; Randal Lewis; David Richards

2003-07-22

We have started a program to compute the electromagnetic form factors of mesons. We discuss the techniques used to compute the pion form factor and present preliminary results computed with domain wall valence fermions on MILC asqtad lattices, as well as Wilson fermions on quenched lattices. These methods can easily be extended to rho-to-gamma-pi transition form factors.