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1.
Transl Psychiatry ; 7(8): e1202, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28809857

RESUMO

Stress during pregnancy may impact subsequent generations, which is demonstrated by an increased susceptibility to childhood and adulthood health problems in the children and grandchildren. Although the importance of the prenatal environment is well reported with regards to future physical and emotional outcomes, little is known about the molecular mechanisms that mediate the long-term consequences of early stress across generations. Recent studies have identified DNA methylation as a possible mediator of the impact of prenatal stress in the offspring. Whether psychosocial stress during pregnancy also affects DNA methylation of the grandchildren is still not known. In the present study we examined the multigenerational hypothesis, that is, grandmaternal exposure to psychosocial stress during pregnancy affecting DNA methylation of the grandchildren. We determined the genome-wide DNA methylation profile in 121 children (65 females and 56 males) and tested for associations with exposure to grandmaternal interpersonal violence during pregnancy. We observed methylation variations of five CpG sites significantly (FDR<0.05) associated with the grandmother's report of exposure to violence while pregnant with the mothers of the children. The results revealed differential methylation of genes previously shown to be involved in circulatory system processes (FDR<0.05). This study provides support for DNA methylation as a biological mechanism involved in the transmission of stress across generations and motivates further investigations to examine prenatal-dependent DNA methylation as a potential biomarker for health problems.


Assuntos
Metilação de DNA , Epigênese Genética , Exposição Materna , Efeitos Tardios da Exposição Pré-Natal/genética , Estresse Psicológico/genética , Adolescente , Criança , Ilhas de CpG , Estudos Transversais , Exposição à Violência/psicologia , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Mães , Gravidez
2.
Curr Med Chem ; 22(34): 3910-21, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26282942

RESUMO

As far back as Melville Wolfrom's acyclic sugar synthesis in the 1960's, synthesis of flexible nucleoside analogues have been an area of interest. This concept, however, went against years of enzyme-substrate binding theory. Hence, acyclic methodology in antiviral drug design did not take off until the discovery and subsequent FDA approval of such analogues as Acyclovir and Tenofovir. More recently, the observation that flexible nucleosides could overcome drug resistance spawned a renewed interest in the field of nucleoside drug design. The next generation of flexible nucleosides shifted the focus from the sugar moiety to the nucleobase. With analogues such as Seley-Radtke "fleximers", and Herdewijn's C5 substituted 2'-deoxyuridines, the area of base flexibility has seen great expansion. More recently, the marriage of these methodologies with acyclic sugars has resulted in a series of acyclic flex-base nucleosides with a wide range of antiviral properties, including some of the first to exhibit anti-coronavirus activity. Various flexible nucleosides and their corresponding nucleobases will be compared in this review.


Assuntos
Antivirais/química , Desenho de Fármacos , Nucleosídeos/química , Antivirais/farmacologia , HIV/efeitos dos fármacos , HIV/enzimologia , Transcriptase Reversa do HIV/antagonistas & inibidores , Transcriptase Reversa do HIV/metabolismo , Humanos , Nucleosídeos/farmacologia , Inibidores da Transcriptase Reversa/química , Inibidores da Transcriptase Reversa/farmacologia , Simplexvirus/efeitos dos fármacos
3.
Transl Psychiatry ; 5: e571, 2015 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-26080088

RESUMO

Stress, particularly when experienced early in life, can have profound implications for mental health. Previous research covering various tissues such as the brain, suggests that the detrimental impact of early-life stress (ELS) on mental health is mediated via epigenetic modifications including DNA methylation. Genes of the hypothalamic-pituitary-adrenal axis--in particular, the glucocorticoid receptor (hGR) gene--stand out as key targets for ELS. Even though the link between hGR methylation and either ELS or psychopathology is fairly well established, the mutually dependent relationships between ELS, DNA methylation and psychopathology remain to be uncovered. The specific psychopathology an individual might develop in the aftermath of stressful events can be highly variable, however, most studies investigating hGR methylation and psychopathology suffer from being limited to a single symptom cluster of mental disorders. Here, we screened volunteers for childhood maltreatment and analyzed whether it associates with hGR methylation in lymphocytes and a range of measures of psychological ill-health. hGR methylation in lymphocytes most likely reflects methylation patterns found in the brain and thus provides valuable insights into the etiology of psychopathology. We find the interaction between childhood maltreatment and hGR methylation to be strongly correlated with an increased vulnerability to psychopathology providing evidence of epigenome × environment interactions. Furthermore, our results indicate an additive effect of childhood maltreatment and hGR methylation in predicting borderline personality disorder (BPD)-associated symptoms, suggesting that the combination of both ELS and DNA methylation that possibly represents unfavorable events experienced even earlier in life poses the risk for BPD.


Assuntos
Sobreviventes Adultos de Maus-Tratos Infantis/psicologia , Maus-Tratos Infantis/psicologia , Metilação de DNA , Interação Gene-Ambiente , Transtornos Mentais/genética , Receptores de Glucocorticoides/genética , Adolescente , Ansiedade/genética , Ansiedade/psicologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/genética , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/psicologia , Transtorno da Personalidade Borderline/genética , Transtorno da Personalidade Borderline/psicologia , Criança , Estudos de Coortes , Depressão/genética , Depressão/psicologia , Epigênese Genética , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Transtornos Mentais/psicologia , Adulto Jovem
4.
Orthopade ; 44(3): 193-202, 2015 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-25319257

RESUMO

BACKGROUND: It is well known that morbidity rates of arthroplasties are inversely related to procedure volume. In the department of orthopaedics at a German medical school, a performance of certification of high-volume center for total hip and knee arthroplasties, called the EndoCert(®) Initiative, was started. This project was initiated by the German society of orthopaedic surgery (DGOOC) to secure the quality of total knee and hip arthroplasties. OBJECTIVES: The aim of this study is to evaluate effects of certification, pathwaycontrolled therapy and quality indicators on outcome in arthroplasty three years after implentation. MATERIALS AND METHODS: Arthroplasties performed in this certified center for total hip and knee arthroplasties were evaluated. Outcome was evaluated after the implementation of quality indicators and clinical pathways. RESULTS: After establishment of certification in the center for total hip and knee arthroplasties morbidity rates decreased as quality increased. CONCLUSION: The implementation of pathway-controlled therapy and quality indicators in a high-volume center for total joint arthroplasties shows better clinical results. Capital investment and efforts are legitimated.


Assuntos
Artroplastia de Quadril/normas , Artroplastia do Joelho/normas , Certificação/normas , Procedimentos Clínicos/normas , Ortopedia/normas , Garantia da Qualidade dos Cuidados de Saúde , Alemanha , Humanos , Sociedades Médicas/normas , Resultado do Tratamento
5.
Transl Psychiatry ; 1: e21, 2011 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-22832523

RESUMO

Prenatal exposure to maternal stress can have lifelong implications for psychological function, such as behavioral problems and even the development of mental illness. Previous research suggests that this is due to transgenerational epigenetic programming of genes operating in the hypothalamic-pituitary-adrenal axis, such as the glucocorticoid receptor (GR). However, it is not known whether intrauterine exposure to maternal stress affects the epigenetic state of these genes beyond infancy. Here, we analyze the methylation status of the GR gene in mothers and their children, at 10-19 years after birth. We combine these data with a retrospective evaluation of maternal exposure to intimate partner violence (IPV). Methylation of the mother's GR gene was not affected by IPV. For the first time, we show that methylation status of the GR gene of adolescent children is influenced by their mother's experience of IPV during pregnancy. As these sustained epigenetic modifications are established in utero, we consider this to be a plausible mechanism by which prenatal stress may program adult psychosocial function.


Assuntos
Metilação de DNA/genética , Regiões Promotoras Genéticas/genética , Receptores de Glucocorticoides/genética , Parceiros Sexuais/psicologia , Violência , Adolescente , Adulto , Criança , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Feminino , Humanos , Relação entre Gerações , Masculino , Troca Materno-Fetal/genética , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Receptores de Glucocorticoides/metabolismo , Receptores de Glucocorticoides/fisiologia , Estudos Retrospectivos , Adulto Jovem
7.
J Thromb Haemost ; 5(1): 102-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17059431

RESUMO

BACKGROUND: Genetically engineered disulfide bonds in B-domain-deleted factor (F) VIII variants (C662-C1828 FVIII and C664-C1826 FVIII) improve FVIIIa stability by blocking A2 domain dissociation because the new disulfide covalently links the A2 and A3 domains in FVIIIa. AIM: The aim of this study was to assess the hypothesis that these variants have physiologically relevant properties because of prolonged thrombin generation and improved clot formation in whole blood. METHODS: Clot-formation properties in whole blood were measured in thromboelastogram assays. The thrombin generation capabilities of the wild-type (WT) FVIII and FVIII variants were determined, and half-lives of FVIIIa variants were determined in fresh whole blood serum. RESULTS: Thromboelastogram assays were performed with fresh, severe hemophilia whole blood reconstituted with variant and WT FVIII. The two disulfide bond-stabilized FVIII variants and WT FVIII had comparable clotting times at all studied concentrations. However, when compared with WT FVIII at low concentrations, the two FVIII variants required only 10% as much FVIII to achieve comparable clot-formation rates, clot-formation times and clot firmness values. The differences between WT and FVIII variants were quite pronounced at low FVIII concentrations. Measurement of the endogenous thrombin potential in FVIII-deficient plasma supplemented with these FVIII variants confirmed that the disulfide bond-stabilized variants supported high levels of thrombin generation at lower concentrations than did WT FVIII. During the course of clot generation in whole blood, the disulfide bond-stabilized FVIIIa variants had approximately 5-fold increased half-lives relative to WT FVIIIa. CONCLUSION: C662-C1828 FVIII and C664-C1826 FVIII have physiologically relevant superior clot-forming properties in a whole blood environment, most likely due to the increased half-life of these FVIIIa variants in whole blood.


Assuntos
Coagulação Sanguínea , Coagulantes/metabolismo , Dissulfetos , Fator VIII/metabolismo , Fator VIIIa/metabolismo , Hemofilia A/sangue , Coagulação Sanguínea/efeitos dos fármacos , Linhagem Celular , Coagulantes/química , Coagulantes/farmacologia , Relação Dose-Resposta a Droga , Estabilidade de Medicamentos , Fator VIII/química , Fator VIII/genética , Fator VIII/farmacologia , Meia-Vida , Hemofilia A/metabolismo , Humanos , Técnicas In Vitro , Mutação , Proteínas Recombinantes/metabolismo , Tromboelastografia , Trombina/metabolismo , Tempo de Trombina , Transfecção , Tempo de Coagulação do Sangue Total
8.
J Thromb Haemost ; 4(10): 2215-22, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16824189

RESUMO

BACKGROUND: Protein S (PS) has activated protein C-independent, direct anticoagulant activity (PS-direct). We reported that both multimers and monomers of affinity-purified PS have PS-direct similar to that in plasma, in contrast to another report. OBJECTIVE: We extended our studies to establish the molecular forms and activity of plasma PS. METHODS: Novel ELISAs were developed that could detect only multimeric, not monomeric, PS because they employed the same monoclonal antibody for capture and detection. PS forms were also examined on native PAGE immunoblots. A new activity assay for PS-direct was applied to plasma and gel-filtered plasma fractions. RESULTS: Plasma PS multimers were clearly demonstrated using the ELISAs; 30-60% of free plasma PS appeared to be multimeric, a proportion similar to that of affinity-purified PS. On immunoblots, plasma PS multimers were more easily detected after gel filtration; plasma PS monomers and several apparent multimers comigrated with respective forms of affinity-purified PS. Antigen elution profiles after gel filtration of plasma revealed at least one major peak of apparent PS multimers (40-55% of free PS appeared multimeric). Biotin-factor Xa could bind to both plasma PS monomers and multimers. Strong plasma PS-direct was demonstrated, and plasma PS monomers, multimers, and PS-C4b-binding protein complexes each reconstituted PS-depleted plasma to similar levels of PS-direct. CONCLUSION: Our data are in disagreement with a report that monomeric purified PS has little PS-direct and that only monomeric PS exists in plasma. We find that both affinity-purified and plasma PS exist as monomers and multimers with similar PS-direct.


Assuntos
Anticoagulantes/farmacologia , Testes de Coagulação Sanguínea/métodos , Proteína S/biossíntese , Proteína S/química , Anticorpos Monoclonais/química , Antígenos/química , Química Clínica/métodos , Cromatografia , Cromatografia em Gel , Ensaio de Imunoadsorção Enzimática , Humanos , Ligantes , Ligação Proteica
9.
J Thromb Haemost ; 4(6): 1315-22, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16706977

RESUMO

BACKGROUND: The utility of purified coagulation factor (F)VIII for treatment of hemophilia A is limited in part by its instability following activation by thrombin, which is caused by spontaneous dissociation of the A2 domain from the activated FVIII (FVIIIa) heterotrimer. To prevent this A2 domain dissociation in FVIIIa, we previously engineered a cysteine pair (C664-C1826) in recombinant FVIII that formed a disulfide bond cross-linking the A2 domain in the heavy chain to the A3 domain in the light chain. This engineered disulfide bond resulted in a more stable FVIIIa. AIMS: Here, we characterize the functional parameters of C664-C1828 FVIII and of a new disulfide bond-stabilized FVIII (C662-C1828 FVIII). METHODS: In order to assess whether these FVIII variants might be good candidates for a new therapeutic agent to treat hemophilia A, we investigated a variety of functional parameters that might affect the in vivo properties of the variants, including half-life of disulfide bond-stabilized FVIII and FVIIIa and the potency of these FVIIIa molecules in the FXase complex. RESULTS: Both disulfide bond-stabilized variants had improved affinity for von Willebrand factor (VWF). In studies of FX activation by purified FIXa and FVIIIa, C662-C1828 FVIIIa had normal activity while C664-C1826 FVIIIa had reduced activity. Both C664-C1826 FVIIIa and C662-C1828 FVIIIa were inactivated by activated protein C (APC) but the rates of inactivation were different. CONCLUSION: Overall, the specific location of the disulfide bridge between the A2 and A3 domains appears to affect functional properties of FVIIIa. In summary, introduction of engineered interdomain disulfides results in FVIIIa variants that resist spontaneous loss of activity while retaining susceptibility to APC proteolytic inactivation and maintaining VWF binding.


Assuntos
Fator IXa/metabolismo , Fator VIII/metabolismo , Fator VIIIa/química , Fator VIIIa/metabolismo , Fator de von Willebrand/metabolismo , Fator VIII/química , Fator VIII/uso terapêutico , Fator VIIIa/genética , Fator VIIIa/uso terapêutico , Hemofilia A/tratamento farmacológico , Mutação , Ligação Proteica , Proteína C/metabolismo , Conformação Proteica , Desnaturação Proteica , Engenharia de Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/uso terapêutico , Ressonância de Plasmônio de Superfície , Trombina/metabolismo
10.
J Thromb Haemost ; 3(9): 2044-56, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16102111

RESUMO

BACKGROUND: Formation of the intrinsic tenase complex is an essential event in the procoagulant reactions that lead to clot formation. The tenase complex is formed when the activated serine protease, Factor IXa (FIXa), and its cofactor Factor VIIIa (FVIIIa) assemble on a phospholipid surface to proteolytically convert the zymogen Factor X (FX) into its active form FXa. The physiological relevance of the tenase complex is evident in hemophilia A or B patients who present with bleeding disorders. OBJECTIVES: The purpose of this study was to establish three-dimensional (3D) models of the FVIIIa-FIXa complex. METHODS: First, we built two new theoretical models of FVIIIa via homology modeling, inter-domain docking and loop simulation algorithms as well as a model for FIXa. This was followed by pseudo-Brownian protein-protein docking in internal coordinates with the ICM (Internal Coordinates Mechanics) program between the two FVIIIa and the FIXa structures. RESULTS: Ten representative models of this complex are presented based on agreements with known experimental data and according to structural criteria. CONCLUSIONS: These novel 3D models will help guide future site directed mutagenesis aimed at improving the functionality of FVIIIa and/or FIXa and will contribute to a better understanding of the role of this macromolecular complex in the blood coagulation cascade.


Assuntos
Coagulação Sanguínea , Fator IXa/química , Fator VIIIa/química , Modelos Moleculares , Algoritmos , Cisteína Endopeptidases/química , Humanos , Complexos Multiproteicos/química , Proteínas de Neoplasias/química , Ligação Proteica , Conformação Proteica , Homologia Estrutural de Proteína
11.
Biol Reprod ; 56(3): 757-63, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9047022

RESUMO

Human semen contains very potent blood clotting activity; for example, seminal serum diluted up to 10,000-fold significantly decreased the recalcification clotting time of blood plasma. This seminal coagulant activity was dependent on factor X and calcium ions, suggesting the presence of a facto X activator. Immunoblotting analysis and immunoadsorption studies confirmed the presence of tissue factor antigen (45 kDa) in semen. Centrifugation studies suggested that tissue factor was membrane associated, and fractionation of seminal serum by gel filtration followed by immunoelectron microscopy revealed that tissue factor antigen was on the prostasome vesicle surface. Tissue factor originated from prostatic fluid and not from seminal vesicle secretions. Tissue factor antigen averaged 21 ng/ml in seminal serum. Hypothetical roles for very high levels of tissue factor in semen include several possibilities. In the event of abrasion and bleeding during intercourse, rapid blood clotting at lesion sites would prevent sperm and seminal components, including infectious agents such as human immunodeficiency virus, from entering the blood stream, generating antibodies, or promoting infectious disease. This could imply that development of infection from semen-borne agents or development of antisperm antibodies in some patients could result from impairment or absence of seminal tissue factor.


Assuntos
Coagulação Sanguínea/fisiologia , Sêmen/fisiologia , Tromboplastina/fisiologia , Adulto , Cromatografia Líquida , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Fator X/fisiologia , Humanos , Immunoblotting , Técnicas In Vitro , Indicadores e Reagentes , Masculino , Microscopia Imunoeletrônica , Testes de Neutralização , Próstata/metabolismo , Próstata/ultraestrutura , Glândulas Seminais/metabolismo , Glândulas Seminais/ultraestrutura , Tromboplastina/química , Tromboplastina/isolamento & purificação
12.
Thromb Haemost ; 75(1): 62-9, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8713781

RESUMO

cDNAs for protein C inhibitor (PCI), prepared from human liver RNA, contained two forms of PCI, designated PCI*A and PCI*B. While PCI*A is identical to the published PCI sequence, PCI*B differs in 4 of 1221 bp and two amino acids, A36V and K86E. Frequencies for the PCI*B allele, determined from genomic DNA, differed among ethnic groups. Frequency distribution and historical migration of modern man suggest that PCI*A arose from the PCI*B allele. Antigen levels in plasma homozygous for PCI*A or PCI*B equalled that of pooled normal plasma. K86E in PCI*B causes a charge alteration in helix D which is likely involved in heparin binding in antithrombin III but not likely involved in glycosaminoglycan binding in PCI. Kinetic studies showed that plasmas homozygous for PCI*A and PCI*B are similar in their APC inhibiting properties and in their heparin sensitivity, consistent with the idea that helix D in PCI is not involved in heparin binding.


Assuntos
Povo Asiático/genética , Heparina/metabolismo , Polimorfismo Genético , Inibidor da Proteína C/genética , População Branca/genética , Alelos , Sequência de Aminoácidos , Sequência de Bases , Gráficos por Computador , Frequência do Gene , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Inibidor da Proteína C/metabolismo
13.
Thromb Haemost ; 74(4): 1079-87, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8560417

RESUMO

cDNAs for protein C inhibitor (PCI) were cloned from human and rhesus monkey liver RNAs by reverse transcription and polymerase chain reaction (PCR) amplification. Sequencing showed that rhesus monkey and human PCI cDNAs were 93% identical. Predicted amino acid sequences differed at 26 of 387 residues. Four of these differences (T352M, N359S, R362K, L363I) were in the reactive center loop that is important for inhibitory specificity, and two were in the N-terminal helix (M8T, E13K) that is implicated in glycosaminoglycan binding. PCI in human or rhesus monkey plasma showed comparable inhibitory activity towards human activated protein C in the presence of 10 U/ml heparin. However, maximal acceleration of the inhibition of activated protein C required 5-fold lower heparin concentration for rhesus monkey than for human plasma, consistent with the interpretation that the additional positive charge (E13K) in a putative-heparin binding region increased the affinity for heparin.


Assuntos
DNA Complementar/genética , Heparina/metabolismo , Inibidor da Proteína C/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar/isolamento & purificação , Humanos , Macaca mulatta , Modelos Moleculares , Dados de Sequência Molecular , Inibidor da Proteína C/metabolismo , Alinhamento de Sequência , Análise de Sequência
15.
Biochem J ; 305 ( Pt 2): 397-403, 1995 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-7832752

RESUMO

Protein S is a plasma factor essential for prevention of thrombosis, partly due to its activity as a cofactor for the plasma anticoagulant protease-activated protein C. To expand knowledge about structure-function relationships in homologous protein S molecules, studies of protein S from different species have been performed. Protein S anti-coagulant activity in human, monkey, bovine, and porcine plasma has been inactivated by purified human C4b binding protein (C4BP) with dose-dependence, suggesting that each protein S can bind human C4BP and that only the free form of each is anti-coagulantly active. Purified porcine protein S has a 10-fold higher Kd for human C4BP than has human protein S. Protein S residues 420-434 provide an essential binding site for the negative regulator C4BP. cDNA sequences show that protein S residues 420-434 are highly conserved in all four species with the notable exception of Lys-429-Ile in porcine protein S. Differences between porcine and human protein S, e.g. Lys-429-Ile, Lys-43-Ala, Ser-197-Leu, Ser 199-Phe, Glu-463-Gly, Lys-571-Glu, Asn-602-Ile, Gln-607-Pro, may contribute to the decreased affinity of porcine protein S for human C4BP. Moreover, the species specificity of cofactor activities of various species of protein S is determined for human versus bovine-activated protein C, and these results, combined with sequence comparisons, agree with previous evidence that the thrombin-sensitive region and the first epidermal growth factor domain of protein S, i.e. residues 47-116, are responsible for recognition of activated protein C.


Assuntos
Macaca mulatta/genética , Proteína S/genética , Suínos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Bovinos , Clonagem Molecular , Complemento C4b/metabolismo , Sequência Conservada , Ensaio de Imunoadsorção Enzimática , Humanos , Immunoblotting , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica , Proteína C/metabolismo , Proteína S/isolamento & purificação , Proteína S/metabolismo , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Relação Estrutura-Atividade
17.
J Clin Invest ; 94(5): 2117-24, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7525654

RESUMO

Protein C inhibitor (PCI) is a serpin that inhibits a number of proteases. PCI is found in urine and binds to kidney epithelial cells. To determine if kidney is a source of PCI, cDNA was produced from human kidney total RNA. Sequencing and restriction mapping showed identity between kidney and liver PCI cDNA sequences. Similar cDNAs were obtained from rhesus monkey kidney and liver RNAs. Conditioned medium from the rhesus monkey kidney cell line CCL7.1 was analyzed on immunoblots, showing a 57,000-D protein band that comigrated with human plasma PCI. Immunohistochemical staining and in situ hybridization of human kidney tissue sections showed that kidney PCI antigen and RNA were confined to tubular cells. The findings are consistent with the idea that PCI is synthesized and localized in kidney tissue where it may provide protease inhibitory activity and suggest that complexes of PCI with urokinase found in human urine may be produced locally in the kidney.


Assuntos
Túbulos Renais/química , Inibidor da Proteína C/análise , Sequência de Bases , DNA Complementar/análise , Humanos , Imuno-Histoquímica , Dados de Sequência Molecular , Inibidor da Proteína C/genética , RNA/análise
18.
Biochem J ; 302 ( Pt 3): 655-64, 1994 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-7524474

RESUMO

Studies with Euglena gracilis and HL-60 cells have assessed the need for intracellular iron in the mechanisms of inhibition of cell growth and DNA damage by H2O2 and bleomycin. Cell culture media were directly depleted of iron in order to deprive cells of nutrient iron. Major pools of cellular iron were reduced in both cell types. Nevertheless, iron bound in e.s.r.-observable haem protein and ribonucleotide diphosphate reductase in HL-60 cells was not decreased. In both control cell populations, there was a concentration-dependent reduction in proliferation and cell survival caused by H2O2. In comparison, the proliferation rates of both iron-deficient cell types were significantly less sensitive to H2O2. H2O2 caused concentration-dependent single-strand breakage in DNA in control HL-60 and Euglena gracilis cells. Iron deficiency reduced the amount of strand breaks in HL-60 cells at each concentration of H2O2 used. Single-strand breakage caused by H2O2 in Euglena gracilis was a direct function of the concentration of iron in which the cells had been grown. Growth inhibition and both single- and double-strand DNA damage caused by bleomycin were substantially reduced or eliminated in iron-deficient cells. Copper bleomycin behaved like metal-free bleomycin when assayed for the capacity to cause DNA damage in iron-normal and iron-deficient HL-60 cells. In contrast, iron bleomycin was equally active under the two conditions in these cells.


Assuntos
Bleomicina/farmacologia , Divisão Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Ferro/fisiologia , Animais , Sítios de Ligação , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/genética , Relação Dose-Resposta a Droga , Espectroscopia de Ressonância de Spin Eletrônica , Euglena gracilis/citologia , Euglena gracilis/efeitos dos fármacos , Euglena gracilis/genética , Ferro/metabolismo , Células Tumorais Cultivadas
19.
Am J Med ; 91(1): 37-44, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1858827

RESUMO

PURPOSE: Hemostatic alterations and elevated tumor necrosis factor/cachectin (TNF alpha) serum levels may contribute to the pathogenesis of organ complications in human Plasmodium falciparum malaria. Therefore, we examined whether altered protein C (PC) and thrombin-antithrombin III (TAT) plasma levels correlated with TNF alpha serum concentrations, parasitemia, and the clinical course of human P. falciparum malaria. PATIENTS AND METHODS: Forty-seven patients with P. falciparum malaria were evaluated prospectively before and during antiparasitic therapy. TNF alpha serum levels were determined by immunoradiometric assay, PC and TAT plasma antigen by enzyme-linked immunosorbent assay, and PC and PC inhibitor-1 (PCI-1) activity levels by functional tests. Cultured endothelial cells were incubated with serum from four patients with malaria and from healthy control subjects and then assayed for procoagulant activity. Northern blot hybridization was used to detect tissue factor mRNA. RESULTS: In vivo, TNF alpha serum concentrations were elevated (median: 38.6 pg/mL; n = 47) while plasma levels of PC (antigen 55.4%; activity 39.0%; n = 47) and PCI-1 (0.56 U/L) were decreased in almost all patients before antiparasitic treatment. At the same time, TAT concentrations were high. These alterations correlated significantly (p less than 0.01) both with the severity of the disease (as defined by organ impairment) and with the number of circulating parasitized erythrocytes. Low PCI-1 activity correlated with low PC activity (p less than 0.001) and antigen (p less than 0.05) levels. The plasma level of coagulation factor IX, another vitamin K-dependent protein, was not significantly changed. In vitro, incubation of endothelial cells with patient serum (severe P. falciparum malaria) increased both endothelial cell procoagulant activity and cytoplasmic tissue factor mRNA levels. CONCLUSION: Elevated levels of TNF alpha and TAT, decreased plasma levels of anticoagulant PC, and the induction of procoagulant activity in endothelial cells by patient serum indicate a shift in the balance of hemostatic activity towards a procoagulant state in P. falciparum malaria. The alterations in TNF alpha, TAT, and PC levels may be a response to infection, since they correlate with parasitemia and are reversed during antiparasitic treatment.


Assuntos
Antitrombina III/análise , Fator IX/análise , Malária/sangue , Plasmodium falciparum , Proteína C/análise , Trombina/análise , Fator de Necrose Tumoral alfa/análise , Animais , Coagulação Sanguínea/fisiologia , Endotélio Vascular/metabolismo , Fibrinogênio/análise , Humanos , Malária/tratamento farmacológico , Tempo de Tromboplastina Parcial , Plasmodium falciparum/isolamento & purificação , Contagem de Plaquetas , Estudos Prospectivos , Proteína C/antagonistas & inibidores , Tempo de Protrombina , RNA Mensageiro/biossíntese
20.
Biochim Biophys Acta ; 1074(1): 74-8, 1991 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-2043683

RESUMO

The highly specific plasminogen activator inhibitor of placental type, PAI-2, occurs in the placenta in a low molecular mass form of 46.6 kDa, and in pregnancy plasma in a (possibly glycosylated) high molecular mass form of 60 kDa. Extensive knowledge is available about the functional properties of PAI-2 as a plasminogen activator inhibitor and about its molecular biology and regulation. Of the several placenta proteins (PP) isolated, one of them, PP10, has a molecular mass of 48 kDa and its occurrence in malignancy and in complications during pregnancy has been the topic of a number of studies, though its properties and physiological significance are unknown. The present findings constitute evidence of immunological identity between PP10 and PAI-2. The sections of the amino acid sequence of PP10 analysed here were found to have identical counterparts in the sequence of the low molecular mass form of PA1-2, but in several preparations PP10 was found to occur in an inactive two-chain form due to cleavage of an Arg-Thr bond, the two peptide chains being linked to each other by a disulphide bridge. The cleavage site is identical to that observed in the reaction between PAI-2 and urokinase. The results make it possible to coordinate and correlate the findings of many separate studies and our own observations on PP10 and PAI-2.


Assuntos
Inativadores de Plasminogênio/imunologia , Proteínas da Gravidez/imunologia , Sequência de Aminoácidos , Cromatografia Líquida de Alta Pressão , Difusão , Glicoproteínas , Humanos , Immunoblotting , Dados de Sequência Molecular , Placenta/química , Inativadores de Plasminogênio/química , Inativadores de Plasminogênio/isolamento & purificação , Proteínas da Gravidez/química , Proteínas da Gravidez/isolamento & purificação , Homologia de Sequência do Ácido Nucleico
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