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1.
Med Sci (Paris) ; 35(8-9): 659-666, 2019.
Artigo em Francês | MEDLINE | ID: mdl-31532378

RESUMO

The renal filtration is ensured by the kidney glomeruli selective for filtering the blood. The main actor of the glomerular filter is the podocyte whose interlaced pedicels bear protein complexes (nephrin, podocin, etc.) creating a molecular sieve (slit diaphragm) to achieve the filtration. Alterations of these podocytes lead to massive proteinuria, which characterizes the nephrotic syndrome. The idiopathic form is one of the most malignant and essentially comprises two entities: minimal change disease and focal segmental glomerulosclerosis. Many observations indicated that (1) immune cells are involved and that (2) there are several permeability factors in the blood that affect the morphology and function of podocytes (slit diaphragm with fractional foot processes fusion/effacement). Evidence for a permeability factor was chiefly derived from remission of proteinuria observed after implantation of a kidney with FSGS in healthy recipients or with other kidney diseases. Today, we are moving towards a multifactorial conception of the nephrotic syndrome where all these barely known factors could be associated according to a sequential kinetic mechanism that needs to be determined.


TITLE: Syndrome néphrotique idiopathique et facteurs circulants - Une Arlésienne ? ABSTRACT: La fonction d'excrétion du rein fait intervenir des glomérules chargés de filtrer sélectivement le sang. L'acteur principal du filtre glomérulaire est le podocyte dont les pédicelles entrelacés portent des complexes moléculaires (néphrine, podocine, etc.) qui sont responsables du fonctionnement de la barrière de filtration (diaphragme de fente). Des altérations de ces podocytes entraînent une protéinurie massive qui caractérise le syndrome néphrotique. Parmi les formes les plus malignes de cette pathologie, se trouve le syndrome néphrotique idiopathique dont la physiopathologie reste inconnue. Ce syndrome regroupe essentiellement deux entités : les lésions glomérulaires minimes et la hyalinose segmentaire et focale. Ces pathologies impliqueraient les cellules du système immunitaire et plusieurs facteurs de perméabilité circulants qui agiraient sur la morphologie et le fonctionnement des podocytes.


Assuntos
Células Sanguíneas/fisiologia , Proteínas Sanguíneas/fisiologia , Síndrome Nefrótica/etiologia , Proteínas Sanguíneas/efeitos adversos , Glomerulosclerose Segmentar e Focal/sangue , Glomerulosclerose Segmentar e Focal/complicações , Glomerulosclerose Segmentar e Focal/fisiopatologia , Humanos , Rim/patologia , Rim/fisiologia , Glomérulos Renais/patologia , Glomérulos Renais/fisiologia , Síndrome Nefrótica/sangue , Síndrome Nefrótica/fisiopatologia , Podócitos/patologia , Podócitos/fisiologia , Proteinúria/sangue , Proteinúria/complicações , Proteinúria/fisiopatologia , Fatores de Risco
2.
Int J Pharm ; 520(1-2): 1-13, 2017 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-28131851

RESUMO

Gene engineered mesenchymal stem cells (MSCs) have been proposed as promising tools for their various applications in biomedicine. Nevertheless, the lack of an effective and safe way to genetically modify these stem cells is still a major obstacle in the current studies. Herein, we designed novel magnetic complexes by assembling cationized pullulan derivatives with magnetic iron oxide nanoparticles for delivering target genes to MSCs. Results showed that this complexes achieved effective gene expression with the assistance of external magnetic field, and resisted the adverse effect induced by serum proteins on the gene delivery. Moreover, neither significant cytotoxicity nor the interference on the osteogenic differentiation to MSCs were observed after magnetofection. Further studies revealed that this effective and serum resistant gene transfection was partly due to the accelerated and enhanced intracellular uptake process driven by external magnetic field. To conclude, the current study presented a novel option for genetic modification of MSCs in an effective, relatively safe and serum compatible way.


Assuntos
Proteínas Sanguíneas/efeitos adversos , Técnicas de Transferência de Genes , Glucanos/química , Nanopartículas de Magnetita/química , Células-Tronco Mesenquimais/metabolismo , Transfecção/métodos , Animais , Sobrevivência Celular , Células Cultivadas , Expressão Gênica/efeitos dos fármacos , Magnetismo , Nanopartículas de Magnetita/ultraestrutura , Masculino , Osteogênese , Ratos
3.
Ugeskr Laeger ; 178(40)2016 Oct 03.
Artigo em Dinamarquês | MEDLINE | ID: mdl-27697119

RESUMO

Non-vitamin K oral anticoagulants (NOACs) are alternatives to vitamin K antagonists and provide consistent anticoagulation with equal or better clinical outcome and no need for routine monitoring. Bleeding is a feared complication of anticoagulants. Until recently, no specific agent has been available for reversal of NOACs. Idarucizumab binds dabigatran for rapid reversal of its activity without procoagulant effects. Andexanet alpha (expected release in 2016) and PER977 are antidotes under clinical development. This article summarizes current and potential future options to antagonize NOACs.


Assuntos
Anticoagulantes/efeitos adversos , Antídotos/uso terapêutico , Proteínas Sanguíneas/antagonistas & inibidores , Inibidores do Fator Xa/farmacologia , Protrombina/antagonistas & inibidores , Administração Oral , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticoagulantes/administração & dosagem , Anticoagulantes/farmacologia , Proteínas Sanguíneas/efeitos adversos , Inibidores do Fator Xa/efeitos adversos , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Humanos , Protrombina/efeitos adversos , Vitamina K/antagonistas & inibidores
4.
J Reprod Dev ; 61(6): 503-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26227108

RESUMO

In mouse somatic cell nuclear transfer (SCNT), polyvinylpyrrolidone (PVP) is typically included in the nuclear donor injection medium. However, the cytotoxicity of PVP, which is injected into the cytoplasm of oocytes, has recently become a cause of concern. In the present study, we determined whether bovine serum albumin deionized with an ion-exchange resin treatment (d-BSA) was applicable to the nuclear donor injection medium in SCNT as an alternative to PVP. The results obtained showed that d-BSA introduced into the cytoplasm of an enucleated oocyte together with a donor nucleus significantly enhanced the rate of in vitro development of cloned embryos to the blastocyst stage compared with that of a conventional nuclear injection with PVP in SCNT. We also defined the enhancing effects of d-BSA on the blastocyst formation rate when d-BSA was injected into the cytoplasm of oocytes reconstructed using the fusion method with a hemagglutinating virus of Japan envelope before oocyte activation. Furthermore, immunofluorescence experiments revealed that the injected d-BSA increased the acetylation levels of histone H3 lysine 9 and histone H4 lysine 12 in cloned pronuclear (PN) and 2-cell embryos. The injection of d-BSA before oocyte activation also increased the production of cloned mouse offspring. These results suggested that intracytoplasmic injection of d-BSA into SCNT oocytes before oocyte activation was beneficial for enhancing the in vitro and in vivo development of mouse cloned embryos through epigenetic modifications to nuclear reprogramming.


Assuntos
Clonagem de Organismos , Técnicas de Transferência Nuclear , Soroalbumina Bovina/administração & dosagem , Acetilação , Animais , Blastocisto/parasitologia , Blastocisto/fisiologia , Proteínas Sanguíneas/administração & dosagem , Proteínas Sanguíneas/efeitos adversos , Transferência Embrionária , Imunofluorescência , Histonas/análise , Iodo , Camundongos , Camundongos Endogâmicos , Injeções de Esperma Intracitoplásmicas
5.
JAMA ; 312(10): 1006-15, 2014 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-25173516

RESUMO

IMPORTANCE: Lipoprotein-associated phospholipase A2 (Lp-PLA2) has been hypothesized to be involved in atherogenesis through pathways related to inflammation. Darapladib is an oral, selective inhibitor of the Lp-PLA2 enzyme. OBJECTIVE: To evaluate the efficacy and safety of darapladib in patients after an acute coronary syndrome (ACS) event. DESIGN, SETTING, AND PARTICIPANTS: SOLID-TIMI 52 was a multinational, double-blind, placebo-controlled trial that randomized 13,026 participants within 30 days of hospitalization with an ACS (non-ST-elevation or ST-elevation myocardial infarction [MI]) at 868 sites in 36 countries. INTERVENTIONS: Patients were randomized to either once-daily darapladib (160 mg) or placebo on a background of guideline-recommended therapy. Patients were followed up for a median of 2.5 years between December 7, 2009, and December 6, 2013. MAIN OUTCOMES AND MEASURES: The primary end point (major coronary events) was the composite of coronary heart disease (CHD) death, MI, or urgent coronary revascularization for myocardial ischemia. Kaplan-Meier event rates are reported at 3 years. RESULTS: During a median duration of 2.5 years, the primary end point occurred in 903 patients in the darapladib group and 910 in the placebo group (16.3% vs 15.6% at 3 years; hazard ratio [HR], 1.00 [95% CI, 0.91-1.09]; P = .93). The composite of cardiovascular death, MI, or stroke occurred in 824 in the darapladib group and 838 in the placebo group (15.0% vs 15.0% at 3 years; HR, 0.99 [95% CI, 0.90-1.09]; P = .78). There were no differences between the treatment groups for additional secondary end points, for individual components of the primary end point, or in all-cause mortality (371 events in the darapladib group and 395 in the placebo group [7.3% vs 7.1% at 3 years; HR, 0.94 [95% CI, 0.82-1.08]; P = .40). Patients were more likely to report an odor-related concern in the darapladib group vs the placebo group (11.5% vs 2.5%) and also more likely to report diarrhea (10.6% vs 5.6%). CONCLUSIONS AND RELEVANCE: In patients who experienced an ACS event, direct inhibition of Lp-PLA2 with darapladib added to optimal medical therapy and initiated within 30 days of hospitalization did not reduce the risk of major coronary events. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01000727.


Assuntos
Síndrome Coronariana Aguda/tratamento farmacológico , Benzaldeídos/uso terapêutico , Proteínas Sanguíneas/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Oximas/uso terapêutico , Idoso , Benzaldeídos/efeitos adversos , Proteínas Sanguíneas/efeitos adversos , Doenças Cardiovasculares/mortalidade , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Isquemia Miocárdica/epidemiologia , Isquemia Miocárdica/prevenção & controle , Isquemia Miocárdica/terapia , Oximas/efeitos adversos , Prevenção Secundária
6.
Ther Umsch ; 68(11): 631-40, 2011 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-22045525

RESUMO

This review describes some natural proteins, which can be employed, either as factor concentrates derived from human plasma or as recombinant drug, to modulate the coagulation system. I will address some biochemical characteristics and the physiological role of von Willebrand factor, the coagulation factors of the extrinsic and intrinsic pathways, and the physiological anticoagulant protein C. In addition, I will detail the pharmacological compounds, which are available for influencing or substituting the coagulation proteins: desmopressin (DDAVP), single coagulation factor concentrates, prothrombin complex concentrates, and protein C concentrate. In particular, I will address some treatment topics of general medical interest, such as the treatment of massive bleeding, the correction of the coagulopathy induced by vitamin K-antagonists in patients with cerebral haemorrhage, and of the coagulopathy of meningococcemia. Finally, I will describe some properties and practical clinical applications of the recombinant anticoagulans lepirudin and bivalirudin, which are derived from hirudin, the natural anticoagulant of the medical leech.


Assuntos
Transtornos da Coagulação Sanguínea/tratamento farmacológico , Fatores de Coagulação Sanguínea/uso terapêutico , Proteínas Sanguíneas/uso terapêutico , Anticoagulantes/efeitos adversos , Anticoagulantes/uso terapêutico , Transtornos da Coagulação Sanguínea/sangue , Fatores de Coagulação Sanguínea/efeitos adversos , Proteínas Sanguíneas/efeitos adversos , Hemorragia Cerebral/sangue , Hemorragia Cerebral/induzido quimicamente , Hemorragia Cerebral/tratamento farmacológico , Hemorragia/sangue , Hemorragia/tratamento farmacológico , Hirudinas/efeitos adversos , Humanos , Fragmentos de Peptídeos/efeitos adversos , Fragmentos de Peptídeos/uso terapêutico , Proteína C/efeitos adversos , Proteína C/uso terapêutico , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Vitamina K/antagonistas & inibidores , Fator de von Willebrand/efeitos adversos , Fator de von Willebrand/uso terapêutico
8.
J Reprod Dev ; 57(1): 99-106, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20962458

RESUMO

There has been no culture system that supports the growth of bovine oocytes for more than 2 weeks. In the present study, bovine secondary follicles were cultured for 4 weeks, and the effects of supplemented protein components and FSH in the culture medium on the growth of the oocytes were examined. The effect of vitrification of secondary follicles on the subsequent oocyte growth was also examined. Secondary follicles (150 to 200 µm in diameter) containing growing oocytes (approximately 60 µm in diameter) were dissected from ovaries and cultured in a medium supplemented with FSH (0, 25 or 50 ng/ml) and one of the following four kinds of protein components: bovine serum albumin (BSA), bovine plasma (BPL), fetal calf serum (FCS) and bovine follicular fluid (BFF). In BSA- and BPL-supplemented media with 0 or 25 ng/ml FSH, more than 50% of follicles showed no degenerative signs during culture, and oocytes significantly increased in size after 4 weeks (P<0.05). Higher percentages of granulosa cell-enclosed oocytes were recovered from the follicles cultured in BPL-supplemented media with 0 and 25 ng/ml FSH, and the oocytes grew to 90 µm or more in diameter. In FCS- and BFF-supplemented media, FSH increased the numbers of degenerating follicles. Next, vitrified-warmed secondary follicles were cultured in BPL-supplemented medium. One third of the follicles showed no degenerative signs, and the oocytes increased in diameter to 88.8 ± 3.1 µm after 4 weeks of culture. These results suggest that a BPL-supplemented medium supports oocyte growth in bovine secondary follicles for 4 weeks, even after vitrification and warming of the follicles.


Assuntos
Proteínas Sanguíneas/metabolismo , Bovinos/fisiologia , Meios de Cultura/química , Oócitos/fisiologia , Preservação de Órgãos/veterinária , Folículo Ovariano/fisiologia , Vitrificação , Animais , Proteínas Sanguíneas/efeitos adversos , Cruzamento/métodos , Tamanho Celular , Criopreservação/veterinária , Feminino , Hormônio Foliculoestimulante/efeitos adversos , Hormônio Foliculoestimulante/metabolismo , Líquido Folicular/metabolismo , Células da Granulosa/citologia , Células da Granulosa/fisiologia , Oócitos/citologia , Oogênese , Técnicas de Cultura de Órgãos/veterinária , Preservação de Órgãos/efeitos adversos , Concentração Osmolar , Folículo Ovariano/citologia , Fatores de Tempo
9.
Thromb Haemost ; 104(1): 157-64, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20390231

RESUMO

The pharmacokinetics and pharmacodynamics of 40k-PEG-rFVIIa, a GlycoPEGylated derivative of recombinant wild-type FVIIa, were compared with rFVIIa in rabbits. The procoagulant effect was determined as the weight of the clot formed in a defined segment of a facial vein. A time course study was conducted where ligation was made 10 minutes, 12 or 24 hours after i.v. injection of equimolar doses of 40k-PEG-FVIIa or rFVIIa (2 mg/kg). This dose was selected based on a dose response study and a duration of effect study with rFVIIa. The clot weight increased with increasing doses of rFVIIa, and the duration of effect correlated with the plasma FVIIa clot activity. The plasma half-life of 40k-PEG-rFVIIa measured as FVIIa clot activity was found to be 25 hours, which was 5-6 times longer than rFVIIa. The aPTT and PT were reduced, and the measured increase in thrombin-antithrombin correlated to the effect on clot formation. Thus, the effect was similar at ligation 10 minutes after administration of 40k-PEG-rFVIIa or rFVIIa. At 12 hours, the effect of rFVIIa was absent while significant effect was seen 12 and 24 hours post dosing with 40k-PEG-rFVIIa. No consumption of platelets or fibrinogen was found and no thrombi formation was seen in histological examination of various organs. In conclusion, 40k-PEG-rFVIIa has shown prolonged duration of effect that correlated to various plasma markers and FVIIa clot activity. In perspective, the data support further clinical development of 40k-PEG-rFVIIa to potentially become a long-acting recombinant treatment option for prophylaxis in haemophilia patients with inhibitors.


Assuntos
Proteínas Sanguíneas/administração & dosagem , Coagulantes/administração & dosagem , Fator VIIa/administração & dosagem , Polietilenoglicóis/química , Síndrome Pós-Trombótica/tratamento farmacológico , Animais , Transtornos da Coagulação Sanguínea , Proteínas Sanguíneas/efeitos adversos , Proteínas Sanguíneas/química , Proteínas Sanguíneas/farmacocinética , Coagulantes/efeitos adversos , Coagulantes/química , Coagulantes/farmacocinética , Relação Dose-Resposta a Droga , Fator VIIa/efeitos adversos , Fator VIIa/química , Fator VIIa/farmacocinética , Feminino , Glicosilação , Humanos , Modelos Animais , Estabilidade Proteica/efeitos dos fármacos , Coelhos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacocinética
10.
Pediatrics ; 121(6): e1599-603, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18458037

RESUMO

OBJECTIVE: The objective of this study was to determine the relationship between the frequency and total volume of intravascular volume administration and the development of intracranial hemorrhage during venoarterial extracorporeal membrane oxygenation. METHODS: In a retrospective, matched, case-control study, 24 newborns who developed an intracranial hemorrhage during venoarterial extracorporeal membrane oxygenation treatment were compared with 40 control subjects. Both groups were analyzed for gestational age, gender, race, Apgar scores at 1 and 5 minutes, birth weight, cardiopulmonary resuscitation before venoarterial extracorporeal membrane oxygenation, age at the start of treatment, duration of treatment, worst arterial blood gas sample preceding treatment, activated clotting time values, need for platelet transfusions, mean blood pressure, and the use of inotropics and steroids before the treatment. For both groups, total number and volume of intravascular infusions of normal saline, pasteurized plasma protein solution, erythrocytes, and platelets during the first 24 hours of treatment were determined. Variables were analyzed in their relationship to intracranial hemorrhage by using univariate and multivariate conditional logistic regression. RESULTS: The only statistically significant difference in patient characteristics between the case patients and control subjects was arterial blood gas values. Newborns who developed intracranial hemorrhage during the treatment received both a statistically significantly higher number and a statistically significantly higher total volume of intravascular volume administrations compared with control patients. After adjustment for pH, Paco(2), and Pao(2) in the multivariate analysis, we found a significant relation between the development of intracranial hemorrhage and >8 infusions or >300 mL of volume infusion in the first 8 hours and >10 infusions in the first 24 hours of treatment. CONCLUSIONS: The number and total volume of intravascular volume administration in the first 8 and 24 hours of venoarterial extracorporeal membrane oxygenation treatment are statistically significantly related to the development of intracranial hemorrhage.


Assuntos
Proteínas Sanguíneas/efeitos adversos , Transfusão de Eritrócitos/efeitos adversos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Hemorragias Intracranianas/etiologia , Transfusão de Plaquetas/efeitos adversos , Cloreto de Sódio/efeitos adversos , Proteínas Sanguíneas/administração & dosagem , Volume Sanguíneo , Estudos de Casos e Controles , Feminino , Humanos , Recém-Nascido , Infusões Parenterais , Masculino , Estudos Retrospectivos , Fatores de Risco , Cloreto de Sódio/administração & dosagem
11.
Surg Neurol ; 66(5): 463-9; discussion 469, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17084186

RESUMO

OBJECTIVE: Leukocyte-endothelial cell interactions appear to play a role in the development of vasospasm after SAH. Using a purely inflammatory protein, LPS, we evaluated the effect of inflammation on the development of chronic vasospasm in the absence of blood and compared it to SAH-induced vasospasm in rabbits. METHODS: Lipopolysaccharide was incorporated into EVAc polymers to produce 20% LPS/EVAc polymers (wt/wt). Rabbits (n = 23) were randomized to 4 experimental groups: (1) empty polymer (n = 6), (2) SAH (n = 5), (3) 0.7 mg/kg polymeric LPS dose (n = 6), and (4) 1.4 mg/kg polymeric LPS dose (n = 6). Blood and polymers were inserted into the cisterna magna. The rabbits were killed 3 days postoperatively, and the basilar arteries were harvested for morphometric analysis. Clinical response and lumen patencies were analyzed using ANOVA and a post hoc Newman-Keuls Multiple Comparisons test. RESULTS: Significant narrowing of the basilar artery was observed by insertion of 20% LPS/EVAc polymers into the subarachnoid space at a polymeric dose of 1.4 mg/kg (actual dose, 66 microg kg(-1) d(-1)) (75.4% +/- 4.2%; P < .01) and by SAH (80.3% +/- 8.1%; P < .01) as compared with the empty polymer group. A trend toward narrowing was observed in the 0.7 mg/kg polymeric LPS dose group (actual dose, 33 microg kg(-1) d(-1)) (85.2% +/- 2.6%; P > .05). Symptoms associated with SAH were noted in 50% of the rabbits in the 0.7 mg/kg LPS group and in 100% of rabbits in the 1.4 mg/kg LPS group. CONCLUSION: Controlled release of LPS into the subarachnoid space of rabbits produced chronic vasospasm in a dose-dependent manner. At a polymeric dose of 1.4 mg/kg, LPS-induced vasospasm was equivalent to that induced by SAH. This suggests that LPS and SAH may induce vasospasm through similar mechanisms and provides further evidence that inflammation plays a central role in the etiology of chronic vasospasm.


Assuntos
Artérias Cerebrais/fisiopatologia , Encefalite/fisiopatologia , Lipopolissacarídeos/administração & dosagem , Hemorragia Subaracnóidea/fisiopatologia , Espaço Subaracnóideo/fisiopatologia , Vasoespasmo Intracraniano/fisiopatologia , Animais , Artéria Basilar/efeitos dos fármacos , Artéria Basilar/fisiopatologia , Proteínas Sanguíneas/efeitos adversos , Proteínas Sanguíneas/metabolismo , Artérias Cerebrais/efeitos dos fármacos , Quimiotaxia de Leucócito/efeitos dos fármacos , Quimiotaxia de Leucócito/fisiologia , Doença Crônica , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacocinética , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Encefalite/etiologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Mediadores da Inflamação/administração & dosagem , Mediadores da Inflamação/metabolismo , Mediadores da Inflamação/farmacocinética , Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacocinética , Polivinil/administração & dosagem , Polivinil/química , Polivinil/farmacocinética , Coelhos , Hemorragia Subaracnóidea/complicações , Espaço Subaracnóideo/efeitos dos fármacos , Grau de Desobstrução Vascular/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Vasoconstrição/fisiologia , Vasoespasmo Intracraniano/etiologia
12.
Proc Natl Acad Sci U S A ; 102(17): 6086-91, 2005 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-15837923

RESUMO

Angiopoietin-like protein 4 (ANGPTL4) is a circulating protein predominantly expressed in adipose tissue and liver. Several recent studies demonstrated that ANGPTL4 is the target gene of peroxisome proliferation activators, the agonists of which are widely used as the antidiabetic and lipid-lowering drugs. Here we provide evidence that ANGPTL4 is a blood-borne hormone directly involved in regulating glucose homeostasis, lipid metabolism, and insulin sensitivity. Adenovirus-mediated expression of ANGPTL4 potently decreased blood glucose and improved glucose tolerance, whereas it induced hyperlipidemia, fatty liver, and hepatomegaly in C57 mice. In db/db diabetic mice, ANGPTL4 treatment reduced hyperglycemia to a normal level, and markedly alleviated glucose intolerance and hyperinsulinemia. Ex vivo studies on primary rat hepatocytes revealed that ANGPTL4 significantly decreased hepatic glucose production and enhanced insulin-mediated inhibition of gluconeogenesis. Serum levels of ANGPTL4 in human subjects inversely correlated with plasma glucose concentrations and HOMA IR, the homeostasis model assessment of insulin resistance. In patients with type 2 diabetes, serum levels of ANGPTL4 were significantly lower than those in healthy subjects, suggesting that the decreased ANGPTL4 could be a causative factor of this disease. These results collectively indicate that ANGPTL4 exerts distinct effects on glucose and lipid metabolism, and that its beneficial effect on glucose homeostasis might be useful for the treatment of diabetes.


Assuntos
Glicemia/metabolismo , Proteínas Sanguíneas/uso terapêutico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Fígado Gorduroso/induzido quimicamente , Hiperlipidemias/induzido quimicamente , Proteína 4 Semelhante a Angiopoietina , Angiopoietinas , Animais , Proteínas Sanguíneas/efeitos adversos , Ensaio de Imunoadsorção Enzimática , Teste de Tolerância a Glucose , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
13.
J Virol Methods ; 125(2): 187-93, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15794989

RESUMO

Specific detection of the pathogenic prion protein, PrP(Sc), is essential for determining the prion clearance capacity of purification processes for therapeutic proteins. Use of a previously described indirect (two-antibody) Western blot assay sometimes resulted in the appearance of non-specific protein bands that interfered with the detection of small amounts of PrP(Sc)-specific signal, limiting the amount of clearance that could be determined for steps so affected. It is shown that these non-specific signals are due to the interaction between immunoglobulin fragments in the sample and the secondary antibody used in the assay. To circumvent this problem, a direct Western blot assay using a prion-specific primary antibody conjugated to the reporter enzyme alkaline phosphatase was developed. Application of the direct Western blot assay resulted in a significant reduction of non-specific signal while retaining the detection sensitivity for PrP(Sc)-specific signal. Therefore, the direct Western blot assay format is an improved tool for determining prion clearance capacity, particularly for immunoglobulin-rich samples.


Assuntos
Proteínas Sanguíneas/efeitos adversos , Western Blotting/métodos , Proteínas PrPSc/farmacocinética , Doenças Priônicas/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Bioensaio , Proteínas Sanguíneas/isolamento & purificação , Cricetinae , Proteínas PrPSc/sangue , Proteínas PrPSc/imunologia , Doenças Priônicas/transmissão
14.
Curr Pharm Biotechnol ; 4(5): 275-82, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14529418

RESUMO

In recent years, natural blood components have been extensively studied as the advanced therapeutic delivery systems. The blood components which can potentially be used as the therapeutic delivery systems include different types of cells, such as erythrocytes and lymphocytes, macromolecular complexes such as lipoproteins and antibody or albumin conjugates and other molecules. This review article covers the progress in this topic, specifically, including the safety issues and the utilization of these component. It can be seen through the literature that the blood components as the therapeutic delivery systems have a number of advantages over traditional pharmaceutical products. The efficacy and practice of the applications, however, require significant amount of development work in the near future.


Assuntos
Proteínas Sanguíneas/administração & dosagem , Portadores de Fármacos/administração & dosagem , Eritrócitos/metabolismo , Linfócitos/metabolismo , Preparações Farmacêuticas/administração & dosagem , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Proteínas Sanguíneas/efeitos adversos , Portadores de Fármacos/efeitos adversos , Eritrócitos/citologia , Eritrócitos/fisiologia , Humanos , Imunoconjugados/administração & dosagem , Imunoconjugados/efeitos adversos , Linfócitos/citologia , Linfócitos/fisiologia
15.
Bone Marrow Transplant ; 31(7): 579-83, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12692625

RESUMO

We investigated the efficacy and safety of autologous serum eye drops for the treatment of severe dry eye after allogeneic haematopoietic stem cell transplantation (SCT). A total of 14 patients (four males and 10 females; median age, 31.0 years) with severe dry eye associated with chronic graft-versus-host disease (cGVHD) were enrolled in this study. All patients were refractory to treatment with conventional artificial tears. Autologous serum eye drops, a solution made of 20% autologous serum in sterile saline, were applied 10 times per eye per day. The patients were evaluated every 4 weeks according to visual acuity, corneal sensitivity, vital staining of the ocular surface, tear dynamics, and subjective assessments of symptoms (complaints scores). The median follow-up period was 19.4 months (range: 4-41 months). After 4 weeks of treatment, significant improvement was observed in both complaint scores (from 33.7+/-12.3 to 23.6+/-10.6 points; P<0.01) and fluorescein scores (from 5.8+/-2.0 to 2.4+/-0.9 points; P<0.005). Significant improvements were observed also in rose-bengal staining and tear break-up time. In seven of the 14 patients, the responses were maintained for 6-41 months (median:19.4+/-8.3 months), while six of the other seven patients required treatment with punctal plugs in addition to autologous serum eye drops. One of these other seven patients developed eczema around the eyelids, after which the treatment was discontinued. No serious adverse events were observed. We conclude that autologous serum eye drops are safe and effective for treating severe dry eye associated with cGVHD and that more efficient control of dry eye may be achieved by the combined use of autologous serum eye drops with punctal plugs.


Assuntos
Proteínas Sanguíneas/administração & dosagem , Síndromes do Olho Seco/tratamento farmacológico , Síndromes do Olho Seco/etiologia , Doença Enxerto-Hospedeiro/complicações , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Adulto , Proteínas Sanguíneas/efeitos adversos , Doença Crônica , Feminino , Humanos , Masculino , Síndromes Mielodisplásicas/terapia , Soluções Oftálmicas/administração & dosagem , Soluções Oftálmicas/efeitos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Transplante Homólogo , Resultado do Tratamento
16.
Eval Health Prof ; 25(1): 130-8, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11868443

RESUMO

In 1998, the Cochrane Injuries Group published the results of a systematic review of human albumin administration in critically ill patients. The results showed that the risk of death in patients receiving albumin was 14%, and the risk of death in patients not receiving albumin was 8%, suggesting that for every 17 critically ill patients treated with albumin there is one extra death. The results were widely reported in the television and print media throughout the world and stimulated an immediate response from the drug regulatory agencies, the plasma products industry, and the medical profession. Despite vigorous attempts by the plasma products industry to limit the effect of the systematic review on albumin sales, the use of albumin declined steeply, showing that evidence from systematic reviews can have an important effect on clinical care.


Assuntos
Albuminas/efeitos adversos , Estado Terminal/mortalidade , Serviços de Informação , Proteínas Sanguíneas/efeitos adversos , Estado Terminal/terapia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Albumina Sérica/deficiência , Choque/tratamento farmacológico , Choque/mortalidade
17.
Semin Vasc Med ; 2(4): 429-39, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16222632

RESUMO

Increasing blood levels of hemostatic variables may increase the risk of thrombosis, while increasing levels of rheological variables which reduce blood flow may increase the risk of ischemic events. Systematic reviews of prospective cohort studies of hemostatic and rheological variables suggest that increasing blood levels of fibrinogen, von Willebrand factor, tissue plasminogen activator antigen, fibrin D-dimer, hematocrit, viscosity, and erythrocyte sedimentation rate may be predictors of risk of coronary heart disease (CHD), but their causal relevance is unknown. At present, data for the associations of other hemostatic variables with CHD, and for the associations of hemostatic variables with stroke, venous thromboembolism, and mortality, is relatively sparse and inconclusive. More detailed syntheses of existing prospective data (such as the Fibrinogen Studies Collaboration), observational studies of CHD and the genetic determinants of these plasma components, as well as large-scale randomized trials should help to determine whether or not these associations are (1) useful in prediction of cardiovascular risk and/or (2) of causal significance.


Assuntos
Proteínas Sanguíneas/efeitos adversos , Doenças Cardiovasculares/etiologia , Hemorreologia , Coagulação Sanguínea/fisiologia , Proteínas Sanguíneas/fisiologia , Doenças Cardiovasculares/fisiopatologia , Hemostasia/fisiologia , Humanos
18.
Transfusion ; 41(4): 449-55, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11316893

RESUMO

BACKGROUND: Experimental evidence from rodent models indicates that blood can contain transmissible spongiform encephalopathy (TSE) infectivity, which suggests a potential risk for TSE transmission via proteins isolated from human plasma. Because methods that can reduce TSE infectivity typically are detrimental to protein function, infectivity must be removed to ensure the safety of these therapeutic proteins. Animal bioassays are conventionally used to detect infectivity, but the pathogenic form of the prion protein (PrP(Sc)) can serve as a marker for TSE infectivity. STUDY DESIGN AND METHODS: Seven plasma protein-purification steps were performed after the plasma intermediates were spiked with TSE-infected material. Resulting fractions were analyzed for PrP(Sc) by using a Western blot assay and for TSE infectivity by using an animal bioassay. Western blots were quantitated by an endpoint dilution analysis, and infectivity titers were calculated by the Spearman-Kärber method. RESULTS: PrP(Sc) partitioning paralleled TSE infectivity partitioning, regardless of the nature of the protein-purification step. The detection ranges for PrP(Sc) and infectivity were 0 to 5.3 log and 1.1 to 8.9 log median infectious dose per unit, respectively. Clearance of PrP(Sc) and infectivity ranged from 1.0 to 6.0 log. CONCLUSION: Purification steps for isolating therapeutic proteins from human plasma showed the removal of both PrP(Sc) and TSE infectivity. PrP(Sc) partitioning coincided with infectivity partitioning, which showed a close relationship between PrP(Sc) and TSE infectivity. By exploiting this association, the in vitro Western blot assay for PrP(Sc) was valuable for estimating the partitioning of TSE infectivity during plasma protein purification.


Assuntos
Proteínas Sanguíneas/efeitos adversos , Doenças Priônicas/transmissão , Príons/análise , Animais , Biomarcadores , Proteínas Sanguíneas/isolamento & purificação , Cricetinae , Humanos
19.
Cell Transplant ; 8(4): 419-25, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10478723

RESUMO

Nafamostat mesilate (NM), a protease inhibitor, possesses a cytoprotective effect and inhibits the activation of complement. The present study investigated whether NM has any protective effect against injury of porcine hepatocytes by human plasma in a bioartificial liver support system. Porcine hepatocytes were harvested and seeded at a density of 2 x 10(5) cells on a 35-mm collagen-coated plate in Dulbecco's modified Eagle's medium (DMEM) with 10% fetal calf serum. Twenty-four hours later, the medium was replaced with human plasma with three concentrations of NM between 3.8 x 10(-5) and 3.8 x 10(-4) M and then cultured for 6 h. The viability of porcine hepatocytes, lactate dehydrogenase (LDH) levels, lidocaine clearance, porcine albumin production, and changes in complement (C3) levels were measured. The viability of porcine hepatocytes in human plasma decreased significantly to 37.7 +/- 11.4% of that in DMEM. NM improved the viability of the hepatocytes, lowered the levels of LDH, and increased lidocaine clearance and albumin production in a concentration-dependent manner. The concentrations of C3, the marker of xenogeneic reactions, did not change significantly, indicating that no hyperacute xenogeneic reaction occurred in our series. Together, our results suggested that NM exerts favorable effects on porcine hepatocytes in human plasma through direct effect such as prevention of protease activity in the plasma membrane of porcine hepatocytes rather than inhibition of complement-dependent immunoreactions.


Assuntos
Proteínas Sanguíneas/efeitos adversos , Guanidinas/farmacologia , Fígado Artificial , Fígado/citologia , Inibidores de Proteases/farmacologia , Albuminas/biossíntese , Anestésicos Locais/farmacocinética , Animais , Benzamidinas , Sobrevivência Celular/efeitos dos fármacos , Transplante de Células , Células Cultivadas , Complemento C3/análise , Complemento C3/farmacologia , Feminino , Humanos , L-Lactato Desidrogenase/análise , Lidocaína/farmacocinética , Fígado/enzimologia , Suínos , Transplante Heterólogo
20.
Ned Tijdschr Geneeskd ; 142(33): 1855-8, 1998 Aug 15.
Artigo em Holandês | MEDLINE | ID: mdl-9856165

RESUMO

According to the results of a systematic review of randomized clinical studies administration of human albumin to critically ill patients is associated with excess mortality, compared with withholding albumin or administration of crystalloid fluids. The study appears to be well done. Also, there are various explanatory pathophysiological mechanisms supporting the association. However, a favourable effect of albumin in certain patient groups cannot be excluded. Alternatives to albumin are available in most clinical situations, but unfortunately, they are not completely without drawbacks. The use of albumin has to be limited; it might only be abolished when a better effect of other fluids, such as synthetic solutions, is demonstrated.


Assuntos
Albuminas/efeitos adversos , Estado Terminal/mortalidade , Albuminas/administração & dosagem , Proteínas Sanguíneas/efeitos adversos , Estado Terminal/terapia , Feminino , Guias como Assunto/normas , Humanos , Masculino , Concentração Osmolar , Substitutos do Plasma/uso terapêutico , Volume Plasmático/efeitos dos fármacos , Ensaios Clínicos Controlados Aleatórios como Assunto , Albumina Sérica/deficiência , Choque/tratamento farmacológico , Choque/mortalidade , Taxa de Sobrevida
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