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1.
J Immunol ; 188(3): 1371-80, 2012 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-22205027

RESUMEN

Class B scavenger receptors (SR-B) are lipoprotein receptors that also mediate pathogen recognition, phagocytosis, and clearance as well as pathogen-induced signaling. In this study we report that three members of the SR-B family, namely, CLA-1, CLA-2, and CD36, mediate recognition of bacteria not only through interaction with cell wall LPS but also with cytosolic chaperonin 60. HeLa cells stably transfected with any of these SR-Bs demonstrated markedly (3- to 5-fold) increased binding and endocytosis of Escherichia coli, LPS, and chaperonin 60 (GroEL) as revealed by both FACS analysis and confocal microscopy imaging. Increased pathogen (E. coli, LPS, and GroEL) binding to SR-Bs was also associated with the dose-dependent stimulation of cytokine secretion in the order of CD36 > CLA-2 > CLA-1 in HEK293 cells. Pathogen-induced IL-6-secretion was reduced in macrophages from CD36- and SR-BI/II-null mice by 40-50 and 30-40%, respectively. Intravenous GroEL administration increased plasma IL-6 and CXCL1 levels in mice. The cytokine responses were 40-60% lower in CD36(-/-) relative to wild-type mice, whereas increased cytokine responses were found in SR-BI/II(-/-) mice. While investigating the discrepancy of in vitro versus in vivo data in SR-BI/II deficiency, SR-BI/II(-/-) mice were found to respond to GroEL administration without increases in either plasma corticosterone or aldosterone as normally seen in wild-type mice. SR-BI/II(-/-) mice with mineralocorticoid replacement demonstrated an ∼40-50% reduction in CXCL1 and IL-6 responses. These results demonstrate that, by recognizing and mediating inflammatory signaling of both bacterial cell wall LPS and cytosolic GroEL, all three SR-B family members play important roles in innate immunity and host defense.


Asunto(s)
Bacterias/inmunología , Antígenos CD36/inmunología , Inflamación/inmunología , Receptores Depuradores de Clase B/inmunología , Transducción de Señal/inmunología , Animales , Chaperonina 60/inmunología , Chaperonina 60/farmacología , Citocinas/metabolismo , Escherichia coli/inmunología , Células HeLa , Humanos , Inmunidad Innata , Lipopolisacáridos/inmunología , Lipopolisacáridos/farmacología , Ratones , Receptores Depuradores de Clase B/deficiencia
2.
J Immunol ; 188(6): 2749-58, 2012 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-22327076

RESUMEN

Class B scavenger receptors (SR-Bs), such as SR-BI/II or CD36, bind lipoproteins but also mediate bacterial recognition and phagocytosis. In evaluating whether blocking receptors can prevent intracellular bacterial proliferation, phagocyte cytotoxicity, and proinflammatory signaling in bacterial infection/sepsis, we found that SR-BI/II- or CD36-deficient phagocytes are characterized by a reduced intracellular bacterial survival and a lower cytokine response and were protected from bacterial cytotoxicity in the presence of antibiotics. Mice deficient in either SR-BI/II or CD36 are protected from antibiotic-treated cecal ligation and puncture (CLP)-induced sepsis, with greatly increased peritoneal granulocytic phagocyte survival (8-fold), a drastic diminution in peritoneal bacteria counts, and a 50-70% reduction in systemic inflammation (serum levels of IL-6, TNF-α, and IL-10) and organ damage relative to CLP in wild-type mice. The survival rate of CD36-deficient mice after CLP was 58% compared with 17% in control mice. When compensated for mineralocorticoid and glucocorticoid deficiency, SR-BI/II-deficient mice had nearly a 50% survival rate versus 5% in mineralo-/glucocorticoid-treated controls. Targeting SR-B receptors with L-37pA, a peptide that functions as an antagonist of SR-BI/II and CD36 receptors, also increased peritoneal granulocyte counts, as well as reduced peritoneal bacteria and bacterium-induced cytokine secretion. In the CLP mouse sepsis model, L-37pA improved survival from 6 to 27%, reduced multiple organ damage, and improved kidney function. These results demonstrate that the reduction of both SR-BI/II- and CD36-dependent bacterial invasion and inflammatory response in the presence of antibiotic treatment results in granulocyte survival and local bacterial containment, as well as reduces systemic inflammation and organ damage and improves animal survival during severe infections.


Asunto(s)
Antígenos CD36/inmunología , Receptores Depuradores de Clase B/inmunología , Sepsis/inmunología , Animales , Antígenos CD36/metabolismo , Modelos Animales de Enfermedad , Granulocitos/inmunología , Granulocitos/metabolismo , Inflamación/inmunología , Inflamación/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microscopía Confocal , Fagocitosis/inmunología , Receptores Depuradores de Clase B/antagonistas & inhibidores , Sepsis/patología
3.
Clin Chem ; 59(5): 752-70, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23386699

RESUMEN

BACKGROUND: The number of circulating LDL particles is a strong indicator of future cardiovascular disease (CVD) events, even superior to the concentration of LDL cholesterol. Atherogenic (primarily LDL) particle number is typically determined either directly by the serum concentration of apolipoprotein B (apo B) or indirectly by nuclear magnetic resonance (NMR) spectroscopy of serum to obtain NMR-derived LDL particle number (LDL-P). CONTENT: To assess the comparability of apo B and LDL-P, we reviewed 25 clinical studies containing 85 outcomes for which both biomarkers were determined. In 21 of 25 (84.0%) studies, both apo B and LDL-P were significant for at least 1 outcome. Neither was significant for any outcome in only 1 study (4.0%). In 50 of 85 comparisons (58.8%), both apo B and LDL-P had statistically significant associations with the clinical outcome, whereas in 17 comparisons (20.0%) neither was significantly associated with the outcome. In 18 comparisons (21.1%) there was discordance between apo B and LDL-P. CONCLUSIONS: In most studies, both apo B and LDL-P were comparable in association with clinical outcomes. The biomarkers were nearly equivalent in their ability to assess risk for CVD and both have consistently been shown to be stronger risk factors than LDL-C. We support the adoption of apo B and/or LDL-P as indicators of atherogenic particle numbers into CVD risk screening and treatment guidelines. Currently, in the opinion of this Working Group on Best Practices, apo B appears to be the preferable biomarker for guideline adoption because of its availability, scalability, standardization, and relatively low cost.


Asunto(s)
Apolipoproteínas B/sangre , Análisis Químico de la Sangre/métodos , Enfermedades Cardiovasculares/sangre , LDL-Colesterol/sangre , Espectroscopía de Resonancia Magnética , Biomarcadores/sangre , Análisis Químico de la Sangre/normas , Enfermedades Cardiovasculares/prevención & control , Ensayos Clínicos como Asunto , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Resultado del Tratamiento
4.
Am J Physiol Lung Cell Mol Physiol ; 302(2): L206-15, 2012 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-22058162

RESUMEN

Apolipoprotein E (apoE) is an endogenous negative regulator of airway hyperreactivity (AHR) and mucous cell metaplasia in experimental models of house dust mite (HDM)-induced airway disease. The gene encoding human apoE is polymorphic, with three common alleles (ε2, ε3, and ε4) reflecting single amino acid substitutions at amino acids 112 and 158. The objective of this study was to assess whether the human apoE alleles modify airway responses to repeated nasal HDM challenges. Mice expressing the human apoE ε2 (huApoE2), ε3 (huApoE3), or ε4 (huApoE4) alleles received nasal HDM challenges, and airway responses were compared with mice expressing the endogenous murine apoE gene (muApoE). huApoE3 mice displayed significant reductions in AHR, mucous cell metaplasia, and airway inflammation compared with muApoE mice. The attenuated severity of airway inflammation in huApoE3 mice was associated with reductions in lung mRNA levels of Th2 and Th17 cytokines, as well as chemokines (CCL7, CCL11, CCL24). huApoE4 mice had an intermediate phenotype, with attenuated AHR and IgE production, compared with muApoE mice, whereas airway inflammation and mucous cell metaplasia were not reduced. In contrast, HDM-induced airway responses were not modified in mice expressing the huApoE2 allele. We conclude that the polymorphic huApoE alleles differentially modulate HDM-induced airway disease, which can be stratified, in rank order of increasing disease severity, ε3 < ε4 < ε2. These results raise the possibility that the polymorphic apoE alleles may modify disease severity in human asthma.


Asunto(s)
Alérgenos/inmunología , Antígenos Dermatofagoides/inmunología , Apolipoproteínas E/genética , Asma/genética , Hiperreactividad Bronquial/genética , Alelos , Sustitución de Aminoácidos , Animales , Apolipoproteínas E/metabolismo , Asma/inmunología , Asma/patología , Hiperreactividad Bronquial/inmunología , Hiperreactividad Bronquial/patología , Quimiocina CCL11/biosíntesis , Quimiocina CCL24/biosíntesis , Quimiocina CCL7/biosíntesis , Citocinas/biosíntesis , Modelos Animales de Enfermedad , Femenino , Técnicas de Sustitución del Gen , Genotipo , Inmunoglobulina E/biosíntesis , Inflamación/genética , Inflamación/inmunología , Pulmón/inmunología , Pulmón/patología , Metaplasia , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Células Th17/inmunología , Células Th2/inmunología
5.
RNA ; 16(5): 1040-52, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20348446

RESUMEN

APOBEC-1 overexpression in liver has been shown to effectively reduce apoB-100 levels. However, nonspecific hypermutation and liver tumor formation potentially related to hypermutation in transgenic animals compromise its potential use for gene therapy. In studying apoB mRNA editing regulation, we found that the core editing auxiliary factor ACF dose-dependently increases APOBEC-1 nonspecific hypermutation and specific editing with variable site sensitivity. Overexpression of APOBEC-1 together with ACF in human hepatic HepG2 cells hypermutated apoB mRNAs 20%-65% at sites 6639, 6648, 6655, 6762, 6802, and 6845, in addition to the normal 90% editing at 6666. The hypermutation activity of APOBEC-1 was decreased to background levels by a single point APOBEC-1 mutation of P29F or E181Q, while 50% of wild-type control editing at the normal site was retained. The hypermutations on both apoB and novel APOBEC-1 target 1 (NAT1) mRNA were also decreased to background levels with P29F and E181Q mutants in rat liver primary culture cells. The loss of hypermutation with the mutants was associated with significantly decreased APOBEC-1/ACF interaction. These data suggest that nonspecific hypermutation induced by overexpressing APOBEC-1 can be virtually eliminated by site-specific mutation, while maintaining specific editing activity at the normal site, reopening the potential use of APOBEC-1 gene therapy for hyperlipidemia.


Asunto(s)
Citidina Desaminasa/genética , Citidina Desaminasa/metabolismo , Mutación , Desaminasas APOBEC-1 , Sustitución de Aminoácidos , Animales , Apolipoproteínas B/genética , Arilamina N-Acetiltransferasa/química , Arilamina N-Acetiltransferasa/genética , Arilamina N-Acetiltransferasa/metabolismo , Secuencia de Bases , Línea Celular , Células Cultivadas , Citidina Desaminasa/química , Cartilla de ADN/genética , Expresión Génica , Hepatocitos/metabolismo , Humanos , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Mutagénesis Sitio-Dirigida , Edición de ARN , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Ratas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
6.
J Biol Chem ; 285(11): 8492-506, 2010 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-20075072

RESUMEN

Serum amyloid A (SAA) is a major acute phase protein involved in multiple physiological and pathological processes. This study provides experimental evidence that CD36, a phagocyte class B scavenger receptor, functions as a novel SAA receptor mediating SAA proinflammatory activity. The uptake of Alexa Fluor 488 SAA as well as of other well established CD36 ligands was increased 5-10-fold in HeLa cells stably transfected with CD36 when compared with mock-transfected cells. Unlike other apolipoproteins that bind to CD36, only SAA induced a 10-50-fold increase of interleukin-8 secretion in CD36-overexpressing HEK293 cells when compared with control cells. SAA-mediated effects were thermolabile, inhibitable by anti-SAA antibody, and also neutralized by association with high density lipoprotein but not by association with bovine serum albumin. SAA-induced cell activation was inhibited by a CD36 peptide based on the CD36 hexarelin-binding site but not by a peptide based on the thrombospondin-1-binding site. A pronounced reduction (up to 60-75%) of SAA-induced pro-inflammatory cytokine secretion was observed in cd36(-/-) rat macrophages and Kupffer cells when compared with wild type rat cells. The results of the MAPK phosphorylation assay as well as of the studies with NF-kappaB and MAPK inhibitors revealed that two MAPKs, JNK and to a lesser extent ERK1/2, primarily contribute to elevated cytokine production in CD36-overexpressing HEK293 cells. In macrophages, four signaling pathways involving NF-kappaB and three MAPKs all appeared to contribute to SAA-induced cytokine release. These observations indicate that CD36 is a receptor mediating SAA binding and SAA-induced pro-inflammatory cytokine secretion predominantly through JNK- and ERK1/2-mediated signaling.


Asunto(s)
Antígenos CD36/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Proteína Amiloide A Sérica/metabolismo , Animales , Sitios de Unión , Antígenos CD36/química , Antígenos CD36/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Colorantes Fluorescentes , Células HeLa , Humanos , Radioisótopos de Yodo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Riñón/citología , Macrófagos del Hígado/metabolismo , Macrófagos/metabolismo , Masculino , Ratones , Ratones Mutantes , Oligopéptidos/metabolismo , Fosforilación/fisiología , Estructura Terciaria de Proteína , Ratas , Ratas Endogámicas WKY , Trombospondina 1/metabolismo , Transfección
7.
J Pharmacol Exp Ther ; 335(1): 140-8, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20605907

RESUMEN

Lecithin cholesterol acyl transferase (LCAT) deficiency is associated with low high-density lipoprotein (HDL) and the presence of an abnormal lipoprotein called lipoprotein X (Lp-X) that contributes to end-stage renal disease. We examined the possibility of using LCAT an as enzyme replacement therapy agent by testing the infusion of human recombinant (r)LCAT into several mouse models of LCAT deficiency. Infusion of plasma from human LCAT transgenic mice into LCAT-knockout (KO) mice rapidly increased HDL-cholesterol (C) and lowered cholesterol in fractions containing very-low-density lipoprotein (VLDL) and Lp-X. rLCAT was produced in a stably transfected human embryonic kidney 293f cell line and purified to homogeneity, with a specific activity of 1850 nmol/mg/h. Infusion of rLCAT intravenously, subcutaneously, or intramuscularly into human apoA-I transgenic mice showed a nearly identical effect in increasing HDL-C approximately 2-fold. When rLCAT was intravenously injected into LCAT-KO mice, it showed a similar effect as plasma from human LCAT transgenic mice in correcting the abnormal lipoprotein profile, but it had a considerably shorter half-life of approximately 1.23 ± 0.63 versus 8.29 ± 1.82 h for the plasma infusion. rLCAT intravenously injected in LCAT-KO mice crossed with human apolipoprotein (apo)A-I transgenic mice had a half-life of 7.39 ± 2.1 h and increased HDL-C more than 8-fold. rLCAT treatment of LCAT-KO mice was found to increase cholesterol efflux to HDL isolated from mice when added to cells transfected with either ATP-binding cassette (ABC) transporter A1 or ABCG1. In summary, rLCAT treatment rapidly restored the normal lipoprotein phenotype in LCAT-KO mice and increased cholesterol efflux, suggesting the possibility of using rLCAT as an enzyme replacement therapy agent for LCAT deficiency.


Asunto(s)
Lipoproteínas/metabolismo , Fosfatidilcolina-Esterol O-Aciltransferasa/farmacología , Animales , Apolipoproteínas E/metabolismo , Colesterol/metabolismo , Ésteres del Colesterol/metabolismo , Cricetinae , Humanos , Infusiones Intravenosas , Metabolismo de los Lípidos/efectos de los fármacos , Lipoproteínas VLDL/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fosfatidilcolina-Esterol O-Aciltransferasa/administración & dosificación , Fosfatidilcolina-Esterol O-Aciltransferasa/genética , Proteínas Recombinantes
8.
Clin Endocrinol (Oxf) ; 72(5): 709-15, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20447070

RESUMEN

CONTEXT: The substitution of liothyronine (L-T3) for levothyroxine (L-T4) is commonly employed during thyroid hormone (TH) withdrawal in preparation for diagnostic and therapeutic interventions on thyroid cancer patients. Presently, only limited data are available on the L-T3 for L-T4 therapeutic substitution. Objective To characterize the pharmcodynamic equivalence of L-T3 and L-T4. DESIGN: Randomized, double-blind, cross-over intervention study. SETTING: NIH clinical center. PATIENTS: Ten thyroidectomized patients. INTERVENTIONS: Study participants were treated with L-T3 or L-T4 with a target TSH >or= 0.5

Asunto(s)
Terapia de Reemplazo de Hormonas , Hipotiroidismo/tratamiento farmacológico , Tiroxina/uso terapéutico , Triyodotironina/uso terapéutico , Área Bajo la Curva , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Hipotiroidismo/sangre , Hipotiroidismo/cirugía , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Equivalencia Terapéutica , Pruebas de Función de la Tiroides , Tiroidectomía , Tirotropina/sangre , Tiroxina/farmacocinética , Resultado del Tratamiento , Triyodotironina/farmacocinética
9.
J Immunol ; 181(10): 7147-56, 2008 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-18981136

RESUMEN

Scavenger receptor CD36 mediates Staphylococcus aureus phagocytosis and initiates TLR2/6 signaling. We analyzed the role of CD36 in the uptake and TLR-independent signaling of various bacterium, including Escherichia coli, Klebsiella pneumoniae, Salmonella typhimurium, S. aureus, and Enterococcus faecalis. Expression of human CD36 in HeLa cells increased the uptake of both gram-positive and gram-negative bacteria compared with the control mock-transfected cells. Bacterial adhesion was associated with pathogen phagocytosis. Upon CD36 transfection, HEK293 cells, which demonstrate no TLR2/4 expression, acquired LPS responsiveness as assessed by IL-8 production. The cells demonstrated a marked 5- to 15-fold increase in cytokine release upon exposure to gram-negative bacteria, while the increase was much smaller (1.5- to 3-fold) with gram-positive bacteria and lipoteichoic acid. CD36 down-regulation utilizing CD36 small interfering RNA reduced cytokine release by 40-50% in human fibroblasts induced by both gram-negative and gram-positive bacteria as well as LPS. Of all MAPK signaling cascade inhibitors tested, only the inhibitor of JNK, a stress-activated protein kinase, potently blocked E. coli/LPS-stimulated cytokine production. NF-kappaB inhibitors were ineffective, indicating direct TLR-independent signaling. JNK activation was confirmed by Western blot analyses of phosphorylated JKN1/2 products. Synthetic amphipathic peptides with an alpha-helical motif were shown to be efficient inhibitors of E. coli- and LPS-induced IL-8 secretion as well as JNK1/2 activation/phosphorylation in CD36-overexpressing cells. These results indicate that CD36 functions as a phagocytic receptor for a variety of bacteria and mediates signaling induced by gram-negative bacteria and LPS via a JNK-mediated signaling pathway in a TLR2/4-independent manner.


Asunto(s)
Infecciones Bacterianas/inmunología , Antígenos CD36/inmunología , MAP Quinasa Quinasa 4/inmunología , Fagocitosis/inmunología , Transducción de Señal/inmunología , Animales , Infecciones Bacterianas/metabolismo , Western Blotting , Antígenos CD36/metabolismo , Línea Celular , Citocinas/biosíntesis , Inhibidores Enzimáticos/farmacología , Fibroblastos/inmunología , Fibroblastos/metabolismo , Fibroblastos/microbiología , Técnica del Anticuerpo Fluorescente , Humanos , Lipopolisacáridos/inmunología , MAP Quinasa Quinasa 4/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Macrófagos/microbiología , Microscopía Confocal , Fagocitosis/efectos de los fármacos , Ratas , Transducción de Señal/efectos de los fármacos , Transfección
10.
Clin Trials ; 7(3): 274-85, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20423926

RESUMEN

BACKGROUND: The prevalence of chronic sleep deprivation is increasing in modern societies with negative health consequences. Recently, an association between short sleep and obesity has been reported. PRIMARY OBJECTIVES: To assess the feasibility of increasing sleep duration to a healthy length (approximately 7(1/2) h) and to determine the effect of sleep extension on body weight. SECONDARY OBJECTIVES: To examine the long-term effects of sleep extension on endocrine (leptin and ghrelin) and immune (cytokines) parameters, the prevalence of metabolic syndrome, body composition, psychomotor vigilance, mood, and quality of life. METHODS: One hundred-fifty obese participants who usually sleep less than 6(1/2) h, are being randomized at a 2:1 ratio to either an Intervention or to a Comparison Group. They are stratified by age (above and below 35) and the presence or absence of metabolic syndrome. During the first 12 months (Efficacy Phase) of the study, participants are evaluated at bi-monthly intervals: the Intervention Group is coached to increase sleep by at least 30-60 min/night, while the Comparison Group maintains baseline sleep duration. In the second (Effectiveness) phase, participants converge into the same group and are asked to increase (Comparison Group) or maintain (Intervention Group) sleep duration and are evaluated at 6-month intervals for an additional 3 years. Non-pharmacological and behavior-based interventions are being utilized to increase sleep duration. Endocrine, metabolic, and psychological effects are monitored. The sleep, energy expenditure, and caloric intake are assessed by activity monitors and food recall questionnaires. At yearly intervals, body composition, abdominal fat, and basal metabolic rate are measured by dual energy X-ray absorptiometry (DXA), computerized tomography (CT), and indirect calorimetry, respectively. RESULTS: As of January 2010, 109 participants had been randomized, 64 to the Intervention Group and 45 to the Comparison Group (76% women, 62% minorities, average age: 40.8 years; BMI: 38.5 kg/m(2)). Average sleep duration at screening was less than 6 h/night, 40.3 h/week. A total of 28 Intervention and 22 Comparison participants had completed the Efficacy Phase. LIMITATIONS: The study is not blinded and the sample size is relatively small. CONCLUSIONS: This proof-of-concept study on a randomized sample will assess whether sleep extension is feasible and whether it influences BMI. Clinical Trials 2010; 7: 274-285. http://ctj.sagepub.com.


Asunto(s)
Obesidad/terapia , Privación de Sueño/terapia , Sueño , Adolescente , Adulto , Ingestión de Energía , Metabolismo Energético , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo , Adulto Joven
11.
Ann Intern Med ; 151(4): 229-40, W49-51, 2009 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-19687490

RESUMEN

BACKGROUND: Extracts of the medicinal plant Tripterygium wilfordii Hook F (TwHF) have been used in China for centuries to treat a spectrum of inflammatory diseases. OBJECTIVE: To compare the benefits and side effects of TwHF extract with those of sulfasalazine for the treatment of active rheumatoid arthritis. DESIGN: Randomized, controlled trial. A computer-generated code with random, permuted blocks was used to assign treatment. SETTING: 2 U.S. academic centers (National Institutes of Health, Bethesda, Maryland, and University of Texas, Dallas, Texas) and 9 rheumatology subspecialty clinics (in Dallas and Austin, Texas; Tampa and Fort Lauderdale, Florida; Arlington, Virginia; Duncanville, Pennsylvania; Wheaton and Greenbelt, Maryland; and Lansing, Michigan). PATIENTS: 121 patients with active rheumatoid arthritis and 6 or more painful and swollen joints. INTERVENTION: TwHF extract, 60 mg 3 times daily, or sulfasalazine, 1 g twice daily. Patients could continue stable doses of oral prednisone or nonsteroidal anti-inflammatory drugs but had to stop taking disease-modifying antirheumatic drugs at least 28 days before randomization. MEASUREMENTS: The primary outcome was the rate of achievement of 20% improvement in the American College of Rheumatology criteria (ACR 20) at 24 weeks. Secondary end points were safety; radiographic scores of joint damage; and serum levels of interleukin-6, cholesterol, cortisol, and adrenocorticotropic hormone. RESULTS: Outcome data were available for only 62 patients at 24 weeks. In a mixed-model analysis that imputed data for patients who dropped out, 65.0% (95% CI, 51.6% to 76.9%) of the TwHF group and 32.8% (CI, 21.3% to 46.0%) of the sulfasalazine group met the ACR 20 response criteria (P=0.001). Patients receiving TwHF also had significantly higher response rates for ACR 50 and ACR 70 in mixed-model analyses. Analyses of only completers showed similar significant differences between the treatment groups. Significant improvement was demonstrated in all individual components of the ACR response, including the Health Assessment Questionnaire disability score. Interleukin-6 levels rapidly and significantly decreased in the TwHF group. Although not statistically significant, radiographic progression was lower in the TwHF group. The frequency of adverse events was similar in both groups. LIMITATIONS: Only 62% and 41% of patients continued receiving TwHF extract and sulfasalazine, respectively, during the 24 weeks of the study. Long-term outcome data were not collected on participants who discontinued treatment. CONCLUSION: In patients who continued treatment for 24 weeks and could also use stable oral prednisone and nonsteroidal anti-inflammatory drugs, attainment of the ACR 20 response criteria was significantly greater with TwHF extract than with sulfasalazine.


Asunto(s)
Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Sulfasalazina/uso terapéutico , Tripterygium , Adulto , Anciano , Antiinflamatorios no Esteroideos/uso terapéutico , Antirreumáticos/efectos adversos , Quimioterapia Combinada , Femenino , Enfermedades Gastrointestinales/inducido químicamente , Humanos , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Fitoterapia/efectos adversos , Extractos Vegetales/efectos adversos , Prednisona/uso terapéutico , Sulfasalazina/efectos adversos
12.
Clin Gastroenterol Hepatol ; 7(4): 487-493, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19250986

RESUMEN

BACKGROUND & AIMS: The use of antibiotics in the primary prophylaxis for spontaneous bacterial peritonitis (SBP) in patients with cirrhosis is controversial. Our purpose was to determine the beneficial effect of fluoroquinolones as compared with placebo in primary prophylaxis of SBP in high-risk patients with cirrhosis by using meta-analysis. METHODS: Medline, Embase, Cochrane, and Web of Science databases were searched in all languages until August 2008 for randomized placebo-controlled studies evaluating the role of fluoroquinolones in primary prevention of SBP in patients with low protein ascites (total ascitic protein, <1.5 g/dL) and without history of SBP. Two investigators independently performed literature search and data extraction, and then another investigator independently reviewed whether the studies met prespecified criteria and rechecked data extraction. Odds ratios (Peto method) for the risk reduction with fluoroquinolones were calculated for each study and combined by using a random-effects model. RESULTS: Four randomized controlled studies met predefined criteria. The odds ratios for developing first episode of SBP, serious infections, and mortality with fluoroquinolone prophylaxis (n = 194) versus placebo (n = 190) were 0.18 (95% confidence interval [CI], 0.09-0.35), 0.18 (95% CI, 0.10-0.32), and 0.60 (95% CI, 0.37-0.97), respectively. All studies were unidirectional in showing the beneficial effect of fluoroquinolone prophylaxis. We were limited by finding few studies with relatively small sample sizes. CONCLUSIONS: Daily oral fluoroquinolone prophylaxis reduces the risk of development of first episode of SBP and mortality in cirrhotic patients with low total protein in the ascitic fluid. Fluoroquinolones might be advisable for the primary prophylaxis of SBP in selected high-risk patients with cirrhosis.


Asunto(s)
Profilaxis Antibiótica/métodos , Infecciones Bacterianas/prevención & control , Fluoroquinolonas/uso terapéutico , Cirrosis Hepática/complicaciones , Peritonitis/prevención & control , Infecciones Bacterianas/mortalidad , Ensayos Clínicos como Asunto , Humanos , Cirrosis Hepática/terapia , Modelos Estadísticos , Peritonitis/mortalidad , Resultado del Tratamiento
13.
Clin Chem ; 55(3): 407-19, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19168552

RESUMEN

BACKGROUND: Low-density lipoprotein cholesterol (LDL-C) has been the cornerstone measurement for assessing cardiovascular risk for nearly 20 years. CONTENT: Recent data demonstrate that apolipoprotein B (apo B) is a better measure of circulating LDL particle number (LDL-P) concentration and is a more reliable indicator of risk than LDL-C, and there is growing support for the idea that addition of apo B measurement to the routine lipid panel for assessing and monitoring patients at risk for cardiovascular disease (CVD) would enhance patient management. In this report, we review the studies of apo B and LDL-P reported to date, discuss potential advantages of their measurement over that of LDL-C, and present information related to standardization. CONCLUSIONS: In line with recently adopted Canadian guidelines, the addition of apo B represents a logical next step to National Cholesterol Education Program Adult Treatment Panel III (NCEP ATPIII) and other guidelines in the US. Considering that it has taken years to educate physicians and patients regarding the use of LDL-C, changing perceptions and practices will not be easy. Thus, it appears prudent to consider using apo B along with LDL-C to assess LDL-related risk for an interim period until the superiority of apo B is generally recognized.


Asunto(s)
Apolipoproteínas B/sangre , Enfermedades Cardiovasculares/sangre , Pruebas de Química Clínica/métodos , Pruebas de Química Clínica/normas , Apolipoproteínas B/genética , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/genética , Enfermedades Cardiovasculares/prevención & control , Humanos , Factores de Riesgo
14.
Cytotherapy ; 11(8): 1016-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19929465

RESUMEN

BACKGROUND AIMS: Bone marrow (BM)-derived cells may repair cardiovascular injury but populations of interest circulate in small numbers. Cytokines such as granulocyte-colony-stimulating factor mobilize cells under investigation for this purpose, including CD133+ but require injections over multiple days and may promote inflammation. The purpose of this study was to evaluate the effects of a novel CXCR4 inhibitor (plerixafor), previously shown to mobilize CD34+ stem cells, on CD133+ mobilization and markers of inflammation. METHODS: Healthy subjects received a single subcutaneous injection of plerixafor in escalating doses: 240 mcg/kg (n = 3), 320 mcg/kg (n = 5) and 400 mcg/kg (n = 7). CD133+ and CD133+/VEGFR-2+ cells were measured by flow cytometry at baseline, then 4-6 h following plerixafor injection. Markers of inflammation in serum were measured at baseline, then again 10 h following injection of the 400 mcg/kg dose. RESULTS: Across all doses, white blood cells increased on average three-fold from baseline values. CD133+ cells increased on average 24-fold (from 616 +/- 141 cells/mL to 14 713 +/- 4423 cells/mL, P = 0.0064) without clear evidence of a dose effect. CD133+/VEGFR-2+ cells ranged from 0 to 20 cells/mL at baseline and from 0 to 124 cells/mL following plerixafor administration, although the rarity of these cells precluded a statistical analysis of this population. C-reactive protein and serum amyloid type A were not increased after the 400 mcg/kg dose. Pro-inflammatory cytokine levels were undetectable before and after plerixafor, except for macrophage inflammatory protein-1 beta, which increased slightly but significantly after the 400 mcg/kg dose of plerixafor (P = 0.0156). CONCLUSIONS: CD133+ cells are mobilized into the circulation following a single injection of the CXCR4 antagonist plerixafor, without clear evidence for systemic activation of inflammation. This effect may be of importance in cell-based approaches for treating cardiovascular diseases.


Asunto(s)
Enfermedades Cardiovasculares/terapia , Movilización de Célula Madre Hematopoyética , Compuestos Heterocíclicos/farmacología , Receptores CXCR4/antagonistas & inhibidores , Antígeno AC133 , Adulto , Antígenos CD/metabolismo , Bencilaminas , Recuento de Células Sanguíneas , Ciclamas , Femenino , Citometría de Flujo , Glicoproteínas/metabolismo , Humanos , Masculino , Péptidos/metabolismo
15.
Ann Intern Med ; 148(7): 519-28, 2008 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-18378948

RESUMEN

BACKGROUND: Lamivudine is increasingly being used to prevent hepatitis B reactivation in patients with cancer who test positive for hepatitis B surface antigen (HBsAg) and are undergoing chemotherapy. PURPOSE: To determine whether preventive lamivudine reduces chemotherapy-induced hepatitis B virus (HBV)-related morbidity and mortality in patients with cancer who test positive for HBsAg. DATA SOURCES: MEDLINE, Ovid MEDLINE, TOXNET, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials were searched in all languages until June 2007. STUDY SELECTION: Clinical trials and cohort studies that reported the efficacy of preventive lamivudine versus control on HBV reactivation in patients who tested positive for HBsAg and were receiving chemotherapy were included. Additional requirements included minimum sample size (>5 participants per treatment group) and reported HBV-related morbidity and mortality data. DATA EXTRACTION: Two investigators independently did literature searches and data extraction, and 2 other investigators independently confirmed study eligibility and data retrieval. DATA SYNTHESIS: Fourteen studies (2 randomized, controlled trials; 8 prospective cohort studies; and 4 retrospective cohort studies) met the predefined criteria for analysis. There were 275 patients in the preventive lamivudine group and 475 control participants for the primary end point of HBV reactivation. With preventive lamivudine, the relative risk for both HBV reactivation and HBV-related hepatitis ranged from 0.00 to 0.21. None of the patients in the preventive lamivudine group developed HBV-related hepatic failure (0 of 108 patients vs. 21 of 162 patients), and only 4 deaths were attributable to HBV (4 of 208 patients vs. 27 of 394 patients) in the preventive lamivudine group. Lamivudine was well tolerated, and no adverse effects were noted. LIMITATIONS: The studies included in the meta-analysis did not consistently report all of the outcomes of interest. Sample sizes were small and only 2 studies had a randomized, controlled design. CONCLUSION: Preventive therapy with lamivudine for patients who test positive for HBsAg and are undergoing chemotherapy may reduce the risk for HBV reactivation and HBV-associated morbidity and mortality.


Asunto(s)
Antineoplásicos/efectos adversos , Antivirales/uso terapéutico , Hepatitis B Crónica/prevención & control , Lamivudine/uso terapéutico , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B Crónica/virología , Humanos , Huésped Inmunocomprometido , Fallo Hepático Agudo/prevención & control , Neoplasias/tratamiento farmacológico , Neoplasias/inmunología , Neoplasias/virología , Activación Viral/efectos de los fármacos
16.
Isr Med Assoc J ; 11(10): 602-5, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20077946

RESUMEN

BACKGROUND: High sensitivity C-reactive protein, a marker of inflammation, has been proposed to stratify coronary artery disease risk and is lowered by HMG-CoA reductase (statin) therapy. However, the reproducibility of persistently elevated hs-CRP levels and association with other markers of inflammation in patients with stable CAD on aggressive statin therapy is unknown. OBJECTIVES: To determine the reproducibility of hs-CRP levels measured within 2 weeks in patients with documented CAD with stable symptoms and to identify associations with other markers of inflammation. METHODS: Levels of hs-CRP were measured twice within 14 days (7 +/- 4) in 23 patients (22 males and 1 female, average age 66 +/- 10 years) with stable CAD and hs-CRP > or = 2.0 mg/L but < or = 10 mg/L at visit 1. All patients had received statins for cholesterol management (low density lipoprotein-cholesterol 84 +/- 25 mg/dl) with no dose change for > 3 months. None had a history or evidence of malignancy, chronic infection or inflammation, or recent trauma. There was no change in medications between visits 1 and 2, and no patient reported a change in symptoms or general health during this interval. White blood cell count and pro- and anti-inflammatory cytokines were measured at both visits. RESULTS: hs-CRP levels tended to be lower at visit 2 (median 2.4 mg/L, range 0.8-11 mg/L) than at visit 1 (median 3.3 mg/L, range 2.0-9.7; P = 0.1793). However, between the two visits hs-CRP levels decreased by more than 1.0 mg/L in 10 patients and increased by more than 1.0 mg/L in 4 patients. Changes in hs-CRP levels were unrelated to changes in levels of white blood cells (P = 0.4353). Of the cytokines tested, only the antiinflammatory cytokine interleukin-1 receptor antagonist and the pro-inflammatory cytokine interleukin-8 were above lower limits of detection, but there were no correlations between changes in these values and changes in hs-CRP (both P > 0.5). CONCLUSIONS: In stable CAD patients on aggressive statin therapy, hs-CRP levels may fluctuate over brief periods in the absence of changes in health, cardiac symptom status and medications, and without corroboration with other measures of inflammation. Accordingly, elevated hs-CRP levels should be interpreted with caution in this setting.


Asunto(s)
Proteína C-Reactiva/metabolismo , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Anciano , Biomarcadores/sangre , Citocinas/sangre , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Estadísticas no Paramétricas , Estrés Psicológico/sangre
17.
Methods Mol Biol ; 1855: 177-201, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30426418

RESUMEN

Immunofixation electrophoresis (IFE) is a technique for the identification of proteins within complex mixtures after separation by either conventional zone electrophoresis or isoelectric focusing. Most commonly antigens (which are often immunoglobulins) are separated by electrophoresis followed by precipitation with specific antibodies in situ. However, immunoglobulins with specific reactivity can be also precipitated with the proper antigens after electrophoresis in reverse or reversed IFE. Because of its great versatility, potentially high sensitivity, ease to perform and customize, and relatively low cost with no requirement for expensive instrumentation, manual IFE remains a valuable tool for both clinical diagnostic testing and research. Any low-viscosity body fluid specimen or, possibly, culture fluid could be tested with IFE if proper antibodies (or antigens in reverse[d] IFE) are available. After pretreatment with chaotropic and/or reducing agents, even high-viscosity specimens might be amenable to testing with IFE.


Asunto(s)
Anticuerpos/aislamiento & purificación , Proteínas/aislamiento & purificación , Humanos , Inmunoelectroforesis , Inmunoprecipitación , Focalización Isoeléctrica , Proteínas/inmunología , Viscosidad
18.
Methods Mol Biol ; 1855: 249-268, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30426422

RESUMEN

Immunoelectrophoresis (IEP) was the first practical method that combined electrophoresis and immunoprecipitation for identifying and characterizing proteins within complex mixtures. Over the years, IEP has been extended to include a variety of techniques and, as a general name, has been applied to virtually any technique that involves electrophoresis and antigen-antibody precipitin reaction for proteins. Because of the diversity in technical details of different IEP versions, the method described here deals only with classic IEP. Although it requires some manual expertise, IEP is versatile, relatively easy to customize, and economical with no need for expensive instrumentation. Further, it can discern identity, partial identity, and nonidentity of the proteins. Any low-viscosity body fluid specimen or, possibly, culture fluid and tissue extract could be tested with IEP if proper antibodies are available. With these attributes, classic IEP remains a valuable tool for clinical diagnostic testing, purity checking of biochemical and pharmaceutical products, and research.


Asunto(s)
Proteínas Sanguíneas/análisis , Inmunoelectroforesis/métodos , Negro de Almidón/química , Animales , Anticuerpos/química , Colorantes/química , Electroforesis en Gel de Agar/economía , Electroforesis en Gel de Agar/instrumentación , Electroforesis en Gel de Agar/métodos , Diseño de Equipo , Humanos , Inmunodifusión/economía , Inmunodifusión/instrumentación , Inmunodifusión/métodos , Inmunoelectroforesis/economía , Inmunoelectroforesis/instrumentación , Conejos
19.
Methods Mol Biol ; 1855: 387-401, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30426434

RESUMEN

Isoelectric focusing (IEF) coupled with immunodetection (immunofixation or immunoblotting) has become the leading technique for the detection and study of oligoclonal bands (OCBs) in cerebrospinal fluid (CSF) and also is increasingly used in other body fluids such as the tear and serum. Limited commercial availability of precast agarose IEF gels for research and a need for customization prompted reporting a detailed general protocol for the preparation and casting of agarose IEF gel along with sample, control, and isoelectric point marker preparation and carrying out the focusing itself for CSF OCBs. However, the method is readily adaptable to the use of other body fluid specimens and, possibly, research specimens such as culture fluids as well.


Asunto(s)
Electroforesis en Gel de Agar/métodos , Focalización Isoeléctrica/métodos , Bandas Oligoclonales/sangre , Bandas Oligoclonales/líquido cefalorraquídeo , Lágrimas/química , Animales , Geles/química , Humanos , Sefarosa/química
20.
Int J Cancer ; 122(5): 1183-8, 2008 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-17990319

RESUMEN

Protein electrophoresis is used for the detection, evaluation and follow-up of monoclonal gammopathy (MG) conditions such as Waldenström macroglobulinemia (WM). Immunofixation electrophoresis (IFE) is currently the most common method for isotyping of monoclonal gammopathy because of its superior sensitivity relative to immunoelectrophoresis (IEP). We designed a study to evaluate the clinicobiological relevance of small monoclonal bands detected by serum protein electrophoresis, IEP, and IFE. Serum protein electrophoresis, IEP, and IFE were used to evaluate possible monoclonal gammopathy in 46 members (29 relatives and 17 nonbloodline spouses) from 3 families with multiple cases of WM. IFE identified small monoclonal bands initially missed by IEP in 5 individuals (2 blood relatives, 3 spouses) among 46 study participants. All bands were IgM type. Twenty-three individuals, including the 2 blood relatives and 2 of 3 spouses with monoclonal gammopathy, were then followed for a median of 17 years (range, 13-25). The monoclonal gammopathy progressed in the 2 relatives but disappeared in the spouses, and new IgM MG developed in 2 additional relatives with a prior history of IgM polyclonal gammopathy. Small monoclonal bands detected by IFE in a familial context may be biologically meaningful, both as phenotypic biomarkers and possibly as predictors of high risk for WM. Polyclonal IgM may also be a marker of genetic susceptibility in WM families. Larger studies are needed to confirm these observations.


Asunto(s)
Electroforesis de las Proteínas Sanguíneas , Electroforesis en Gel de Agar , Inmunoelectroforesis , Macroglobulinemia de Waldenström/sangre , Macroglobulinemia de Waldenström/diagnóstico , Adulto , Anciano , Femenino , Humanos , Inmunoglobulina M/sangre , Masculino , Persona de Mediana Edad , Linaje , Fenotipo , Sensibilidad y Especificidad
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