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2.
Hernia ; 27(1): 55-62, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36284067

RESUMO

BACKGROUND: Abdominal wall hernia (AWH) affects mental health and mental health questions are frequently included within Patient-Reported Outcome Measures (PROMS) for this patient population. However, these questions have not been informed by the subjective lived experiences of mental health in AWH patients. This study is the first to qualitatively examine how AWH affects patients' mental health. METHODS: Fifteen patients were interviewed from a purposive sample of AWH patients until no new themes emerged. Interviews explored patient thoughts and experiences of AWH and mental health. Data were examined using Interpretative Phenomenological Analysis (IPA). RESULTS: Three key themes pertaining to mental health were identified: "psychological and emotional distress", "identity disruption" and "coping mechanisms and support systems". CONCLUSION: Our findings illustrate that AWH is a pathology that can have a significant detrimental impact on people's mental health. This impact has implications for patient care and can be treated and managed through better psychological support. This support may positively affect AWH patient's experience and outcomes in terms of quality of life. This paper provides recommendations for improved AWH patient care in regard to mental health.


Assuntos
Hérnia Ventral , Saúde Mental , Humanos , Qualidade de Vida , Herniorrafia , Hérnia Ventral/epidemiologia , Assistência ao Paciente
3.
J Thromb Haemost ; 15(4): 709-720, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28109042

RESUMO

Essentials Recombinant factor VIII (FVIII) is known to be expressed at a low level in cell culture. To increase expression, we used codon-optimization of a B-domain deleted FVIII (BDD-FVIII). This resulted in 7-fold increase of the expression level in cell culture. The biochemical properties of codon-optimized BDD-FVIII were similar to the wild-type protein. SUMMARY: Background Production of recombinant factor VIII (FVIII) is challenging because of its low expression. It was previously shown that codon-optimization of a B-domain-deleted FVIII (BDD-FVIII) cDNA resulted in increased protein expression. However, it is well recognized that synonymous mutations may affect the protein structure and function. Objectives To compare biochemical properties of a BDD-FVIII variants expressed from codon-optimized and wild-type cDNAs (CO and WT, respectively). Methods Each variant of the BDD-FVIII was expressed in several independent Chinese hamster ovary (CHO) cell lines, generated using a lentiviral platform. The proteins were purified by two-step affinity chromatography and analyzed in parallel by PAGE-western blot, mass spectrometry, circular dichroism, surface plasmon resonance, and chromogenic, clotting and thrombin generation assays. Results and conclusion The average yield of the CO was 7-fold higher than WT, whereas both proteins were identical in the amino acid sequences (99% coverage) and very similar in patterns of the molecular fragments (before and after thrombin cleavage), glycosylation and tyrosine sulfation, secondary structures and binding to von Willebrand factor and to a fragment of the low-density lipoprotein receptor-related protein 1. The CO preparations had on average 1.5-fold higher FVIII specific activity (activity normalized to protein mass) than WT preparations, which was attributed to better preservation of the CO structure as a result of considerably higher protein concentrations during the production. We concluded that the codon-optimization of the BDD-FVIII resulted in significant increase of its expression and did not affect the structure-function properties.


Assuntos
Códon , Fator VIII/genética , Engenharia de Proteínas , Animais , Células CHO , Linhagem Celular , Cricetinae , Cricetulus , DNA Complementar/metabolismo , Fator VIII/metabolismo , Vetores Genéticos , Glicosilação , Humanos , Lentivirus , Mutação , Fragmentos de Peptídeos/genética , Estrutura Secundária de Proteína , Relação Estrutura-Atividade , Tirosina/química
4.
Am J Transplant ; 17(1): 272-280, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27376583

RESUMO

Allograft transplantation into sensitized recipients with antidonor antibodies results in accelerated antibody-mediated rejection (AMR), complement activation, and graft thrombosis. We have developed a membrane-localizing technology of wide applicability that enables therapeutic agents, including anticoagulants, to bind to cell surfaces and protect the donor endothelium. We describe here how this technology has been applied to thrombin inhibitors to generate a novel class of drugs termed thrombalexins (TLNs). Using a rat model of hyperacute rejection, we investigated the potential of one such inhibitor (thrombalexin-1 [TLN-1]) to prevent acute antibody-mediated thrombosis in the donor organ. TLN-1 alone was able to reduce intragraft thrombosis and significantly delay rejection. The results confirm a pivotal role for thrombin in AMR in vivo. This approach targets donor organs rather than the recipient and is intended to be directly translatable to clinical use.


Assuntos
Rejeição de Enxerto/prevenção & controle , Falência Renal Crônica/cirurgia , Transplante de Rim/efeitos adversos , Peptídeos/farmacologia , Trombina/antagonistas & inibidores , Trombose/prevenção & controle , Animais , Taxa de Filtração Glomerular , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Testes de Função Renal , Masculino , Prognóstico , Ratos , Ratos Endogâmicos Lew , Fatores de Risco , Trombose/etiologia
5.
Anaesth Intensive Care ; 44(6): 758-761, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27832565

RESUMO

Nicotine replacement therapy (NRT) is a common first-line treatment to prevent nicotine withdrawal in smokers. However, available literature reports conflicting results regarding its efficacy and safety in critically ill patients. The objective of this study was to evaluate the relationship between NRT in smokers in the intensive care unit (ICU) and outcomes. This case-control study was conducted in a university-affiliated tertiary hospital ICU. Over a period of five years, 126 active smokers who received transdermal NRT were matched to 126 active smokers who did not receive NRT. The groups were case-matched for sex, age and Acute Physiology and Chronic Health Evaluation II (APACHE II) score. The primary outcome was administration of antipsychotic medication. Secondary outcomes included use of physical restraints, 30-day mortality, and ventilation requirements. Antipsychotic medication was prescribed in 43 (34.1%) patients who received NRT compared to 14 (11.1%) in controls (P <0.01). Physical restraints were used in 37 (29.4%) patients who received NRT, compared to 12 (9.5%) of controls (P <0.01). The 30-day mortality and number of patients intubated was not statistically different between groups. Average length of intubation time was greater in the NRT group (2.56 days; standard deviation 4.16) compared to the control group (1.44 days; standard deviation 2.68) (P=0.012). The use of NRT to prevent nicotine withdrawal in ICU patients is associated with increased use of antipsychotic medication and physical restraint, and with prolonged mechanical ventilation.


Assuntos
Estado Terminal , Nicotina/efeitos adversos , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Tabagismo/tratamento farmacológico , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Nicotina/administração & dosagem , Estudos Retrospectivos , Fumar
6.
Cell Death Discov ; 1: 15051, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27551480

RESUMO

We previously demonstrated PAR2 starts upstreamed with tissue factor (TF) and factor VII (FVII), inhibited autophagy via mTOR signaling in HCC. However, the mechanism underlying for merging functions of PAR2 with the coagulation system in HCC progression remained unclear. The present study aimed to investigate the role of TF, FVII and PAR2 in tumor progression of HCC. The expressions of TF, FVII and PAR2 from HCC specimens were evaluated by immunohistochemical stains and western blotting. We found that the expression of FVII, but not TF and PAR2, directly related to the vascular invasion and the clinical staging. Importantly, a lower level of FVII expression was significantly associated with the longer disease-free survival. The addition of FVII but not TF induced the expression of PAR2 and phosphorylation of ERK1/2, whereas knockdown of FVII decreased PAR2 expression and ERK1/2 phosphorylation in HCC cell lines. Furthermore, levels of phosphor-TSC2 (Ser664) were increased after treatment with FVII and PAR2 agonist whereas these were significantly abolished in the presence of a potent and specific MEK/ERK inhibitor U0126. Moreover, mTOR knockdown highly reduced Hep3B migration, which could be reverted by FVII but not TF and PAR2. These results indicated that FVII/PAR2 signaling through MEK/ERK and TSC2 axis for mTOR activation has potent effects on the migration of HCC cells. In addition, FVII/PAR2 signaling elicits an mTOR-independent signaling, which promotes hepatoma cell migration in consistent with the clinical observations. Our study indicates that levels of FVII, but not TF, are associated with tumor migration and invasiveness in HCC, and provides clues that evaluation of FVII expression in HCC may be useful as a prognostic indicator in patients with HCC and may form an alternative target for further therapy.

7.
J Thromb Haemost ; 11(5): 963-74, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23516969

RESUMO

BACKGROUND: CD34(+) α-smooth muscle actin (SMA)(+) cells mediate intimal hyperplasia (IH) after mechanical endoluminal injury. We previously found that IH is tissue factor (TF) dependent. The precise phenotype of the CD34(+) cells mediating IH is unknown and the mechanisms of TF are also unknown. OBJECTIVE: To define the phenotype of cells mediating IH and compare the effects of inhibiting TF on different subsets of CD34(+) cells. METHODS: Endoluminal injury was induced in C57BL/6 and two strains of mice expressing a human tissue factor pathway inhibitor (hTFPI) fusion protein on different subsets of CD34(+) cells. Confocal microscopy, immunocytofluorescence and real-time PCR were used to determine phenotype. RESULTS: Neointimal cells in C57BL/6 mice were defined as a subset of fibrocytes (CD34(+) CD45(+) collagen-1(+) ) expressing SMA, CD31, TIE-2, CXCR4 and CXCL12. Similar cells circulated post-injury and were also found in mice expressing hTFPI on CD34(+) CD31(+) cells, though in these mice, hTFPI inhibited CD31(+) fibrocyte hyperplasia, so no IH developed. Mice with hTFPI on all CD34(+) α-SMA(+) cells repaired arteries back to a pre-injured state. No CD31(+) fibrocytes were found in these mice unless an anti-hTFPI antibody was administered. Similar findings in protease activated receptor (PAR)-1-deficient mice suggested hTFPI prevented thrombin signaling through PAR-1. In vitro, thrombin increased the number of CD31(+) fibrocytes. CONCLUSIONS: Inhibition of TF on CD31(+) fibrocytes inhibits IH whereas inhibition on all CD34(+) α-SMA(+) cells (or PAR-1 deficiency) inhibits the appearance of CD31(+) fibrocytes and promotes repair. These data enhance our understanding of IH and suggest novel ways to promote regenerative repair.


Assuntos
Fibroblastos/patologia , Hiperplasia/patologia , Tromboplastina/fisiologia , Túnica Íntima/patologia , Animais , Fibroblastos/imunologia , Imunofenotipagem , Camundongos , Reação em Cadeia da Polimerase em Tempo Real
9.
Gene Ther ; 19(9): 936-46, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22071970

RESUMO

The efficient delivery of genetic material to the developing fetal brain represents a powerful research tool and a means to supply therapy in a number of neonatal lethal neurological disorders. In this study, we have delivered vectors based upon adenovirus serotype 5 (Ad5) and adeno-associated virus (AAV) pseudotypes 2/5, 2/8 and 2/9 expressing green fluorescent protein to the E16 fetal mouse brain. One month post injection, widespread caudal to rostral transduction of neural cells was observed. In discrete areas of the brain these vectors produced differential transduction patterns. AAV2/8 and 2/9 produced the most extensive gene delivery and had similar transduction profiles. All AAV pseudotypes preferentially transduced neurons whereas Ad5 transduced both neurons and glial cells. None of the vectors elicited any significant microglia-mediated immune response when compared with control uninjected mice. Whole-body imaging and immunohistological evaluation of brains 9 months post injection revealed long-term expression using these non-integrating vectors. These data will be useful in targeting genetic material to discrete or widespread areas of the fetal brain with the purpose of devising therapies for early neonatal lethal neurodegenerative disease and for studying brain development.


Assuntos
Adenoviridae/genética , Encéfalo/metabolismo , Dependovirus/genética , Técnicas de Transferência de Genes , Vetores Genéticos , Animais , Encéfalo/embriologia , Feminino , Proteínas de Fluorescência Verde/genética , Camundongos , Neuroglia/metabolismo , Neurônios/metabolismo , Transdução Genética
11.
Appl Environ Microbiol ; 76(3): 695-700, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19966023

RESUMO

Filters rated as having a 0.2-microm pore size (0.2-microm-rated filters) are used in laboratory and manufacturing settings for diverse applications of bacterial and particle removal from process fluids, analytical test articles, and gasses. Using Hydrogenophaga pseudoflava, a diminutive bacterium with an unusual geometry (i.e., it is very thin), we evaluated passage through 0.2-microm-rated filters and the impact of filtration process parameters and bacterial challenge density. We show that consistent H. pseudoflava passage occurs through 0.2-microm-rated filters. This is in contrast to an absence of significant passage of nutritionally challenged bacteria that are of similar size (i.e., hydrodynamic diameter) but dissimilar geometry.


Assuntos
Comamonadaceae , Filtração/instrumentação , Poluentes Atmosféricos , Bactérias , Técnicas Bacteriológicas/instrumentação , Contagem de Colônia Microbiana , Comamonadaceae/ultraestrutura , Meios de Cultura , Desinfecção/instrumentação , Contaminação de Medicamentos , Indústria Farmacêutica/instrumentação , Monitoramento Ambiental/instrumentação , Água Doce , Membranas Artificiais , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Esterilização/instrumentação , Microbiologia da Água , Purificação da Água/instrumentação
12.
J Thromb Haemost ; 7(7): 1106-13, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19422457

RESUMO

BACKGROUND: Mouse tissue factor pathway inhibitor (TFPI) is produced in three alternatively spliced isoforms that differ in domain structure and mechanism for cell surface binding. Tissue expression of TFPI isoforms in mice was characterized as an initial step for identification of their physiological functions. METHODS AND RESULTS: Sequence homology demonstrates that TFPIalpha existed over 430 Ma while TFPIbeta and TFPIgamma evolved more recently. In situ hybridization studies of heart and lung did not reveal any cells exclusively expressing a single isoform. Although our previous studies have demonstrated that TFPIalpha mRNA is more prevalent than TFPIbeta or TFPIgamma mRNA in mouse tissues, western blot studies demonstrated that TFPIbeta is the primary protein isoform produced in adult tissues, while TFPIalpha is expressed during embryonic development and in placenta. Consistent with TFPIbeta as the primary isoform produced within adult vascular beds, the TFPI isoform in mouse plasma migrates like TFPIbeta in SDS-PAGE and mice have a much smaller heparin-releasable pool of plasma TFPIalpha than humans. CONCLUSIONS: The data demonstrate that alternatively spliced isoforms of TFPI are temporally expressed in mouse tissues at the level of protein production. TFPIalpha and TFPIbeta are produced in embryonic tissues and in placenta while adult tissues produce almost exclusively TFPIbeta.


Assuntos
Processamento Alternativo , Lipoproteínas/genética , Sequência de Aminoácidos , Animais , Western Blotting , Sequência Conservada , Ensaio de Imunoadsorção Enzimática , Feminino , Hibridização In Situ , Lipoproteínas/química , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Miocárdio/metabolismo , Placenta/metabolismo , RNA Mensageiro/genética , Homologia de Sequência de Aminoácidos
13.
Gene Ther ; 15(6): 443-51, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18004401

RESUMO

Targeted delivery of biological agents to atherosclerotic plaques may provide a novel treatment and/or useful tool for imaging of atherosclerosis in vivo. However, there are no known viral vectors that possess the desired tropism. Two plaque-targeting peptides, CAPGPSKSC (CAP) and CNHRYMQMC (CNH) were inserted into the capsid of adeno-associated virus 2 (AAV2) to assess vector retargeting. AAV2-CNH produced significantly higher levels of transduction than unmodified AAV2 in human, murine and rat endothelial cells, whereas transduction of nontarget HeLa cells was unaltered. Transduction studies and surface plasmon resonance suggest that AAV2-CNH uses membrane type 1 matrix metalloproteinase as a surface receptor. AAV2-CAP only produced higher levels of transduction in rat endothelial cells, possibly because the virus was found to be affected by proteasomal degradation. In vivo substantially higher levels of both peptide-modified AAV2 vectors was detected in the brachiocephalic artery (site of advanced atherosclerotic plaques) and aorta, whereas reduced levels were detected in all other organs examined. These results suggest that in the AAV2 platform the peptides are exposed on the capsid surface in a way that enables efficient receptor binding and so creates effective atherosclerotic plaque targeted vectors.


Assuntos
Aterosclerose/terapia , Dependovirus/genética , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Animais , Apolipoproteínas E/genética , Linhagem Celular , Dependovirus/metabolismo , Marcação de Genes , Engenharia Genética , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Heparina/metabolismo , Humanos , Metaloproteinase 1 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fragmentos de Peptídeos/genética , Ligação Proteica , Ratos , Ressonância de Plasmônio de Superfície , Transdução Genética/métodos , Transgenes
14.
Am J Transplant ; 7(3): 499-506, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17229071

RESUMO

Coagulation proteases are involved in generating fibrin after vascular injury (hemostasis) but they also have multiple other effects, many of which are mediated independently of fibrin generation, via interactions with specific cell membrane-expressed "protease activated receptors". In inflammation, this family of proteins has a complex influence, the facets of which are still incompletely understood, though a common feature in different models appears to be amplification of innate signals that are initially generated by pathogenic elements or, in the context of transplantation, ischemia or anti-graft antibodies, for instance. There is increasing evidence that these proteases may also have specific effects on cells involved in adaptive immunity and on cells that mediate chronic inflammation and fibrosis. Understanding whether these effects are relevant in the responses generated against transplanted organs is important, as it could lead ultimately to the development of novel ways to promote long-term graft survival.


Assuntos
Fatores de Coagulação Sanguínea/fisiologia , Sobrevivência de Enxerto , Transplante de Órgãos , Peptídeo Hidrolases/fisiologia , Trombina/fisiologia , Trombose/enzimologia , Animais , Coagulação Sanguínea , Humanos , Imunidade , Imunossupressores/efeitos adversos , Inflamação/enzimologia , Inflamação/imunologia , Camundongos , Receptores de Trombina/agonistas
15.
J Thromb Haemost ; 4(10): 2191-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16803463

RESUMO

BACKGROUND: Coagulation proteins promote neointimal hyperplasia and vascular remodelling after vessel injury, but the precise mechanisms by which they act in vivo remain undetermined. OBJECTIVES: This study, using an injury model in which the neointima is derived from bone marrow (BM)-derived cells, compared inhibition of tissue factor or thrombin on either BM-derived or existing vascular smooth muscle cells. METHODS: Two transgenic (Tg) mouse strains expressing membrane-tethered tissue factor pathway inhibitor (TFPI) or hirudin (Hir) fusion proteins driven by an alpha smooth muscle actin (SMA) promoter were generated (alpha-TFPI-Tg and alpha-Hir-Tg) and the phenotype after wire-induced endovascular injury was compared with that in wild-type (WT) controls. RESULTS: WT mice developed progressive neointimal expansion, whereas injury in either Tg was followed by repair back to a preinjured state. This was also seen when WT mice were reconstituted with BM from Tg mice but not when Tgs were reconstituted with WT BM, in which injury was followed by slowly progressive neointimal expansion. Injection of CD34+ cells from Tg mice into injured WT mice resulted in the accumulation of fusion protein-expressing cells from day 3 onwards and an absence of neointimal hyperplasia in those areas. CONCLUSIONS: Neointimal development after wire-induced endovascular injury in mice was completely inhibited when BM-derived cells infiltrating the damaged artery expressed membrane tethered anticoagulant fusion proteins under an alpha-SMA promoter. These findings enhance our understanding of the pathological role that coagulation proteins play in vascular inflammation.


Assuntos
Anticoagulantes/metabolismo , Antígenos CD34/biossíntese , Células da Medula Óssea/metabolismo , Membrana Celular/metabolismo , Regulação da Expressão Gênica , Proteínas Recombinantes de Fusão/metabolismo , Células-Tronco/metabolismo , Animais , Aorta/metabolismo , Arteriosclerose/terapia , Vasos Sanguíneos/patologia , Artérias Carótidas/patologia , Humanos , Inflamação , Camundongos , Camundongos Transgênicos , Músculo Liso/metabolismo , Fenótipo
16.
Biochem Soc Trans ; 33(Pt 4): 796-801, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16042601

RESUMO

P450s (cytochrome P450 mono-oxygenases) are a superfamily of haem-containing mono-oxygenase enzymes that participate in a wide range of biochemical pathways in different organisms from all of the domains of life. To facilitate their activity, P450s require sequential delivery of two electrons passed from one or more redox partner enzymes. Although the P450 enzymes themselves show remarkable similarity in overall structure, it is increasingly apparent that there is enormous diversity in the redox partner systems that drive the P450 enzymes. This paper examines some of the recent advances in our understanding of the biodiversity of the P450 redox apparatus, with a particular emphasis on the redox systems in the pathogen Mycobacterium tuberculosis.


Assuntos
Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Biodiversidade , Sistema Enzimático do Citocromo P-450/genética , Transporte de Elétrons , Ferredoxinas/química , Ferredoxinas/metabolismo , Flavina-Adenina Dinucleotídeo/metabolismo , Flavodoxina/química , Flavodoxina/metabolismo , Genoma Bacteriano , Modelos Moleculares , Mycobacterium tuberculosis/enzimologia , Mycobacterium tuberculosis/genética , NADP/metabolismo , Oxirredução , Conformação Proteica
17.
Br J Haematol ; 123(3): 496-501, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14617013

RESUMO

We report a kindred in which two siblings suffered spontaneous venous thromboses in the second decade of life. Further investigation showed reduced coagulation factor V (FV) activity and activated protein C resistance (APCR) ratio but no other thrombophilic abnormalities. The reduction in APCR ratio persisted in a modified APCR assay in which FV activity was normalized between test and control plasmas. Analysis of the FV gene showed that the thrombotic individuals had a complex genotype that included two novel point mutations c.529G>T and c.1250T>C resulting in FV E119X and FV I359T substitutions inherited on different alleles. Individuals in the kindred with FV E119X or FV I359T substitutions alone were asymptomatic. We suggest that the FV I359T substitution confers pro-thrombotic risk and APCR, but that this is only clinically manifest when co-inherited with the FV E119X allele. The FV I359T substitution creates a new consensus sequence for N-linked glycosylation within the FV heavy chain and we speculate that this abnormal glycosylation may disrupt activated protein C-mediated proteolysis of the variant FV and FVa.


Assuntos
Resistência à Proteína C Ativada/genética , Fator V/genética , Mutação Puntual , Trombose/genética , Resistência à Proteína C Ativada/diagnóstico , Adolescente , Genótipo , Humanos , Masculino , Linhagem , Análise de Sequência de DNA , Trombose/diagnóstico
18.
J Thromb Haemost ; 1(9): 1935-44, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12941034

RESUMO

UNLABELLED: Coagulation factors (F)VIIa, FXa and thrombin are implicated in cellular responses in vascular, mesenchymal and inflammatory cells. Fibroblasts are the most abundant cells in connective tissue, and damage to blood vessels places coagulation factors in contact with these and other cell types. OBJECTIVES: To investigate cellular responses of primary dermal fibroblasts to FVIIa, FXa and thrombin by following changes in expression of candidate proteins: monocyte chemotactic protein-1 (MCP-1), interleukin-8 (IL-8), interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF), and to determine the expression of receptors implicated in signaling by these coagulation factors. METHODS: Steady-state mRNA levels were quantified by RNase protection assay, and protein secretion by ELISA. PAR gene expression was assessed by ribonuclease protection assay and conventional and quantitative reverse-transcription-polymerase chain reaction. RESULTS: FVIIa did not induce the candidate genes. In contrast, FXa and thrombin induced MCP-1 mRNA and protein secretion strongly, IL-8 moderately, and IL-6 weakly. Neither FXa nor thrombin induced VEGF mRNA or protein secretion, although FXa induced VEGF protein secretion in lung fibroblasts. Comparison of the presence of candidate receptors in the two fibroblast subtypes demonstrated higher levels of PAR-1 and PAR-3 in lung fibroblasts relative to their dermal counterparts and the additional expression of PAR-2. CONCLUSIONS: FXa and thrombin induce expression of MCP-1, IL-8 and IL-6, and distribution and expression of PARs on dermal fibroblasts is reduced relative to their lung counterparts. Tissue origin may influence the cellular response of fibroblasts to coagulation proteases.


Assuntos
Fatores de Coagulação Sanguínea/farmacologia , Fibroblastos/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Pele/citologia , Células Cultivadas , Quimiocina CCL2/genética , Fator VIIa/farmacologia , Fator X/farmacologia , Fibroblastos/metabolismo , Humanos , Interleucina-6/genética , Interleucina-8/genética , Pulmão/citologia , RNA Mensageiro/análise , RNA Mensageiro/efeitos dos fármacos , Receptor PAR-1/genética , Receptor PAR-2/genética , Receptores de Trombina/genética , Trombina/farmacologia , Fator A de Crescimento do Endotélio Vascular/genética
19.
J Thromb Haemost ; 1(7): 1487-94, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12871284

RESUMO

In mammalian blood coagulation, five proteases (factor VII [FVII]; factor IX [FIX]; factor X [FX]; protein C [PC] and prothrombin [PT]) act with five cofactors (tissue factor [TF]; factor V [FV]; factor VIII [FVIII]; thrombomodulin and protein S) to control the generation of fibrin. Biochemical evidence, molecular cloning data and comparative sequence analysis support the existence of all components of this network in all jawed vertebrates, and strongly suggest that it evolved before the divergence of teleosts over 430 million years ago. Phylogenetic analysis of the amino acid sequences of the Gla-EGF1-EGF2-SP domain serine proteases (FVII, FIX, FX, PC) and the A domain-containing cofactors (FV and FVIII) strongly supports the evolution of the blood coagulation network through two rounds of gene duplication, and supports the hypothesis that vertebrate evolution benefited from two global genome duplications. The jawless vertebrates (hagfish and lamprey) that diverged over 450 million years ago have a blood coagulation network involving TF, PT and fibrinogen. Preliminary evidence indicates that they may have a smaller complement of Gla-EGF1-EGF2-SP domain proteins, suggesting the existence of a 'primitive' coagulation system in jawless vertebrates.


Assuntos
Hemostasia/fisiologia , Animais , Evolução Biológica , Fator IX/química , Fator VII/química , Fator X/química , Fibrinogênio/química , Humanos , Modelos Biológicos , Modelos Genéticos , Filogenia , Proteína C/química , Estrutura Terciária de Proteína , Protrombina/química
20.
J Thromb Haemost ; 1(1): 139-46, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12871551

RESUMO

Inhibitor antibody formation is a complication of factor VIII (FVIII) replacement therapy due to a failure to synthesize sufficient FVIII protein to induce immune tolerance. The incidence of nonsense mutations in inhibitor patients is high, however, this association is variable according to the position of the mutation. We have studied the effect of nonsense mutations on accumulation of FVIII mRNA, protein translation and secretion. Appropriately processed mRNA was detected in cells transfected with wild-type R1966X and R2116X expression constructs and no evidence of nonsense-mediated decay was observed. All constructs directed the translation of detectable intracellular FVIII antigen, however, secreted FVIII was detected only in conditioned media of cells transfected with wild-type cDNA. We have also analyzed ectopic FVIII mRNA transcripts in the lymphocytes of six hemophilia A patients with nonsense mutations (Q139X, R583X, R1941X, R1966X and two unrelated patients with R2116X). FVIII mRNA was detectable in every case. In R1941X and R1966X only normally spliced transcripts were present. In Q139X, R583X and R2116X aberrantly spliced transcripts were observed with two distinct patterns in two individuals with the R2116X mutation. No correlation between mutation, transcript pattern and incidence of inhibitor development was apparent.


Assuntos
Códon sem Sentido/genética , Códon sem Sentido/imunologia , Fator VIII/genética , Fator VIII/imunologia , Processamento Alternativo/genética , Animais , Anticorpos/sangue , Anticorpos/genética , Anticorpos/imunologia , Antígenos/genética , Sequência de Bases , Células CHO , Códon sem Sentido/metabolismo , Cricetinae , DNA Complementar/genética , DNA Complementar/metabolismo , Fator VIII/metabolismo , Hemofilia A/sangue , Hemofilia A/genética , Hemofilia A/imunologia , Humanos , Linfócitos/imunologia , Linfócitos/metabolismo , Mutação Puntual , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Transfecção
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