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1.
Med Sci (Paris) ; 35(8-9): 659-666, 2019.
Artículo en Francés | MEDLINE | ID: mdl-31532378

RESUMEN

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.


Asunto(s)
Células Sanguíneas/fisiología , Proteínas Sanguíneas/fisiología , Síndrome Nefrótico/etiología , Proteínas Sanguíneas/efectos adversos , Glomeruloesclerosis Focal y Segmentaria/sangre , Glomeruloesclerosis Focal y Segmentaria/complicaciones , Glomeruloesclerosis Focal y Segmentaria/fisiopatología , Humanos , Riñón/patología , Riñón/fisiología , Glomérulos Renales/patología , Glomérulos Renales/fisiología , Síndrome Nefrótico/sangre , Síndrome Nefrótico/fisiopatología , Podocitos/patología , Podocitos/fisiología , Proteinuria/sangre , Proteinuria/complicaciones , Proteinuria/fisiopatología , Factores de Riesgo
2.
Int J Pharm ; 520(1-2): 1-13, 2017 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-28131851

RESUMEN

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.


Asunto(s)
Proteínas Sanguíneas/efectos adversos , Técnicas de Transferencia de Gen , Glucanos/química , Nanopartículas de Magnetita/química , Células Madre Mesenquimatosas/metabolismo , Transfección/métodos , Animales , Supervivencia Celular , Células Cultivadas , Expresión Génica/efectos de los fármacos , Magnetismo , Nanopartículas de Magnetita/ultraestructura , Masculino , Osteogénesis , Ratas
3.
Ugeskr Laeger ; 178(40)2016 Oct 03.
Artículo en Danés | MEDLINE | ID: mdl-27697119

RESUMEN

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.


Asunto(s)
Anticoagulantes/efectos adversos , Antídotos/uso terapéutico , Proteínas Sanguíneas/antagonistas & inhibidores , Inhibidores del Factor Xa/farmacología , Protrombina/antagonistas & inhibidores , Administración Oral , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticoagulantes/administración & dosificación , Anticoagulantes/farmacología , Proteínas Sanguíneas/efectos adversos , Inhibidores del Factor Xa/efectos adversos , Hemorragia/inducido químicamente , Hemorragia/tratamiento farmacológico , Humanos , Protrombina/efectos adversos , Vitamina K/antagonistas & inhibidores
4.
J Reprod Dev ; 61(6): 503-10, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26227108

RESUMEN

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.


Asunto(s)
Clonación de Organismos , Técnicas de Transferencia Nuclear , Albúmina Sérica Bovina/administración & dosificación , Acetilación , Animales , Blastocisto/parasitología , Blastocisto/fisiología , Proteínas Sanguíneas/administración & dosificación , Proteínas Sanguíneas/efectos adversos , Transferencia de Embrión , Técnica del Anticuerpo Fluorescente , Histonas/análisis , Yodo , Ratones , Ratones Endogámicos , Inyecciones de Esperma Intracitoplasmáticas
5.
JAMA ; 312(10): 1006-15, 2014 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-25173516

RESUMEN

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.


Asunto(s)
Síndrome Coronario Agudo/tratamiento farmacológico , Benzaldehídos/uso terapéutico , Proteínas Sanguíneas/uso terapéutico , Infarto del Miocardio/tratamiento farmacológico , Oximas/uso terapéutico , Anciano , Benzaldehídos/efectos adversos , Proteínas Sanguíneas/efectos adversos , Enfermedades Cardiovasculares/mortalidad , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Infarto del Miocardio/epidemiología , Isquemia Miocárdica/epidemiología , Isquemia Miocárdica/prevención & control , Isquemia Miocárdica/terapia , Oximas/efectos adversos , Prevención Secundaria
6.
Ther Umsch ; 68(11): 631-40, 2011 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-22045525

RESUMEN

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.


Asunto(s)
Trastornos de la Coagulación Sanguínea/tratamiento farmacológico , Factores de Coagulación Sanguínea/uso terapéutico , Proteínas Sanguíneas/uso terapéutico , Anticoagulantes/efectos adversos , Anticoagulantes/uso terapéutico , Trastornos de la Coagulación Sanguínea/sangre , Factores de Coagulación Sanguínea/efectos adversos , Proteínas Sanguíneas/efectos adversos , Hemorragia Cerebral/sangre , Hemorragia Cerebral/inducido químicamente , Hemorragia Cerebral/tratamiento farmacológico , Hemorragia/sangre , Hemorragia/tratamiento farmacológico , Hirudinas/efectos adversos , Humanos , Fragmentos de Péptidos/efectos adversos , Fragmentos de Péptidos/uso terapéutico , Proteína C/efectos adversos , Proteína C/uso terapéutico , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/uso terapéutico , Vitamina K/antagonistas & inhibidores , Factor de von Willebrand/efectos adversos , Factor de von Willebrand/uso terapéutico
8.
J Reprod Dev ; 57(1): 99-106, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20962458

RESUMEN

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.


Asunto(s)
Proteínas Sanguíneas/metabolismo , Bovinos/fisiología , Medios de Cultivo/química , Oocitos/fisiología , Preservación de Órganos/veterinaria , Folículo Ovárico/fisiología , Vitrificación , Animales , Proteínas Sanguíneas/efectos adversos , Cruzamiento/métodos , Tamaño de la Célula , Criopreservación/veterinaria , Femenino , Hormona Folículo Estimulante/efectos adversos , Hormona Folículo Estimulante/metabolismo , Líquido Folicular/metabolismo , Células de la Granulosa/citología , Células de la Granulosa/fisiología , Oocitos/citología , Oogénesis , Técnicas de Cultivo de Órganos/veterinaria , Preservación de Órganos/efectos adversos , Concentración Osmolar , Folículo Ovárico/citología , Factores de Tiempo
9.
Thromb Haemost ; 104(1): 157-64, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20390231

RESUMEN

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.


Asunto(s)
Proteínas Sanguíneas/administración & dosificación , Coagulantes/administración & dosificación , Factor VIIa/administración & dosificación , Polietilenglicoles/química , Síndrome Postrombótico/tratamiento farmacológico , Animales , Trastornos de la Coagulación Sanguínea , Proteínas Sanguíneas/efectos adversos , Proteínas Sanguíneas/química , Proteínas Sanguíneas/farmacocinética , Coagulantes/efectos adversos , Coagulantes/química , Coagulantes/farmacocinética , Relación Dosis-Respuesta a Droga , Factor VIIa/efectos adversos , Factor VIIa/química , Factor VIIa/farmacocinética , Femenino , Glicosilación , Humanos , Modelos Animales , Estabilidad Proteica/efectos de los fármacos , Conejos , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacocinética
10.
Pediatrics ; 121(6): e1599-603, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18458037

RESUMEN

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.


Asunto(s)
Proteínas Sanguíneas/efectos adversos , Transfusión de Eritrocitos/efectos adversos , Oxigenación por Membrana Extracorpórea/efectos adversos , Hemorragias Intracraneales/etiología , Transfusión de Plaquetas/efectos adversos , Cloruro de Sodio/efectos adversos , Proteínas Sanguíneas/administración & dosificación , Volumen Sanguíneo , Estudios de Casos y Controles , Femenino , Humanos , Recién Nacido , Infusiones Parenterales , Masculino , Estudios Retrospectivos , Factores de Riesgo , Cloruro de Sodio/administración & dosificación
11.
Surg Neurol ; 66(5): 463-9; discussion 469, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17084186

RESUMEN

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.


Asunto(s)
Arterias Cerebrales/fisiopatología , Encefalitis/fisiopatología , Lipopolisacáridos/administración & dosificación , Hemorragia Subaracnoidea/fisiopatología , Espacio Subaracnoideo/fisiopatología , Vasoespasmo Intracraneal/fisiopatología , Animales , Arteria Basilar/efectos de los fármacos , Arteria Basilar/fisiopatología , Proteínas Sanguíneas/efectos adversos , Proteínas Sanguíneas/metabolismo , Arterias Cerebrales/efectos de los fármacos , Quimiotaxis de Leucocito/efectos de los fármacos , Quimiotaxis de Leucocito/fisiología , Enfermedad Crónica , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/farmacocinética , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Encefalitis/etiología , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Mediadores de Inflamación/administración & dosificación , Mediadores de Inflamación/metabolismo , Mediadores de Inflamación/farmacocinética , Lipopolisacáridos/metabolismo , Lipopolisacáridos/farmacocinética , Polivinilos/administración & dosificación , Polivinilos/química , Polivinilos/farmacocinética , Conejos , Hemorragia Subaracnoidea/complicaciones , Espacio Subaracnoideo/efectos de los fármacos , Grado de Desobstrucción Vascular/efectos de los fármacos , Vasoconstricción/efectos de los fármacos , Vasoconstricción/fisiología , Vasoespasmo Intracraneal/etiología
12.
Proc Natl Acad Sci U S A ; 102(17): 6086-91, 2005 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-15837923

RESUMEN

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.


Asunto(s)
Glucemia/metabolismo , Proteínas Sanguíneas/uso terapéutico , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hígado Graso/inducido químicamente , Hiperlipidemias/inducido químicamente , Proteína 4 Similar a la Angiopoyetina , Angiopoyetinas , Animales , Proteínas Sanguíneas/efectos adversos , Ensayo de Inmunoadsorción Enzimática , Prueba de Tolerancia a la Glucosa , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL
13.
J Virol Methods ; 125(2): 187-93, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15794989

RESUMEN

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.


Asunto(s)
Proteínas Sanguíneas/efectos adversos , Western Blotting/métodos , Proteínas PrPSc/farmacocinética , Enfermedades por Prión/metabolismo , Fosfatasa Alcalina/metabolismo , Animales , Bioensayo , Proteínas Sanguíneas/aislamiento & purificación , Cricetinae , Proteínas PrPSc/sangre , Proteínas PrPSc/inmunología , Enfermedades por Prión/transmisión
14.
Curr Pharm Biotechnol ; 4(5): 275-82, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14529418

RESUMEN

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.


Asunto(s)
Proteínas Sanguíneas/administración & dosificación , Portadores de Fármacos/administración & dosificación , Eritrocitos/metabolismo , Linfocitos/metabolismo , Preparaciones Farmacéuticas/administración & dosificación , Animales , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/efectos adversos , Proteínas Sanguíneas/efectos adversos , Portadores de Fármacos/efectos adversos , Eritrocitos/citología , Eritrocitos/fisiología , Humanos , Inmunoconjugados/administración & dosificación , Inmunoconjugados/efectos adversos , Linfocitos/citología , Linfocitos/fisiología
15.
Bone Marrow Transplant ; 31(7): 579-83, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12692625

RESUMEN

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.


Asunto(s)
Proteínas Sanguíneas/administración & dosificación , Síndromes de Ojo Seco/tratamiento farmacológico , Síndromes de Ojo Seco/etiología , Enfermedad Injerto contra Huésped/complicaciones , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Leucemia Mielógena Crónica BCR-ABL Positiva/terapia , Adulto , Proteínas Sanguíneas/efectos adversos , Enfermedad Crónica , Femenino , Humanos , Masculino , Síndromes Mielodisplásicos/terapia , Soluciones Oftálmicas/administración & dosificación , Soluciones Oftálmicas/efectos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Trasplante Homólogo , Resultado del Tratamiento
16.
Eval Health Prof ; 25(1): 130-8, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11868443

RESUMEN

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.


Asunto(s)
Albúminas/efectos adversos , Enfermedad Crítica/mortalidad , Servicios de Información , Proteínas Sanguíneas/efectos adversos , Enfermedad Crítica/terapia , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Riesgo , Albúmina Sérica/deficiencia , Choque/tratamiento farmacológico , Choque/mortalidad
17.
Semin Vasc Med ; 2(4): 429-39, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16222632

RESUMEN

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.


Asunto(s)
Proteínas Sanguíneas/efectos adversos , Enfermedades Cardiovasculares/etiología , Hemorreología , Coagulación Sanguínea/fisiología , Proteínas Sanguíneas/fisiología , Enfermedades Cardiovasculares/fisiopatología , Hemostasis/fisiología , Humanos
18.
Transfusion ; 41(4): 449-55, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11316893

RESUMEN

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.


Asunto(s)
Proteínas Sanguíneas/efectos adversos , Enfermedades por Prión/transmisión , Priones/análisis , Animales , Biomarcadores , Proteínas Sanguíneas/aislamiento & purificación , Cricetinae , Humanos
19.
Cell Transplant ; 8(4): 419-25, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10478723

RESUMEN

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.


Asunto(s)
Proteínas Sanguíneas/efectos adversos , Guanidinas/farmacología , Hígado Artificial , Hígado/citología , Inhibidores de Proteasas/farmacología , Albúminas/biosíntesis , Anestésicos Locales/farmacocinética , Animales , Benzamidinas , Supervivencia Celular/efectos de los fármacos , Trasplante de Células , Células Cultivadas , Complemento C3/análisis , Complemento C3/farmacología , Femenino , Humanos , L-Lactato Deshidrogenasa/análisis , Lidocaína/farmacocinética , Hígado/enzimología , Porcinos , Trasplante Heterólogo
20.
Ned Tijdschr Geneeskd ; 142(33): 1855-8, 1998 Aug 15.
Artículo en Holandés | MEDLINE | ID: mdl-9856165

RESUMEN

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.


Asunto(s)
Albúminas/efectos adversos , Enfermedad Crítica/mortalidad , Albúminas/administración & dosificación , Proteínas Sanguíneas/efectos adversos , Enfermedad Crítica/terapia , Femenino , Guías como Asunto/normas , Humanos , Masculino , Concentración Osmolar , Sustitutos del Plasma/uso terapéutico , Volumen Plasmático/efectos de los fármacos , Ensayos Clínicos Controlados Aleatorios como Asunto , Albúmina Sérica/deficiencia , Choque/tratamiento farmacológico , Choque/mortalidad , Tasa de Supervivencia
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