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Objectives: Using multicentre ultrasound (US) cohort data among patients with rheumatoid arthritis (RA), we aimed to identify baseline factors that permit differentiation between two patient cohorts achieving US remission and clinical remission, and to determine the factors contributing to the discrepancy.Method: We reviewed 248 Japanese patients diagnosed with RA who underwent treatment with biological disease-modifying anti-rheumatic drugs at 13 centres. We performed US assessments of the synovia of 22 joints. We assessed the percentages of patients with clinical remission and US remission, defined as total power Doppler scores of 0 at 12 months.Results: The 87 patients who achieved US remission were divided into a group that achieved both clinical and US remission (n = 53) and a group that achieved US remission only (n = 34). Baseline factors that were significantly and independently associated with clinical remission at 12 months among patients who also achieved US remission included short disease duration, the presence of concomitant methotrexate use, and low patient global assessment score (p < 0.05, p < 0.05, and p < 0.005, respectively).Conclusions: RA patients with baseline high patient global assessment scores and long disease duration at baseline were unlikely to achieve clinical remission even after achieving US remission. Objective joint assessments using US provide additional information of potential importance for the management of RA.
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Artritis Reumatoide , Antirreumáticos/uso terapéutico , Artritis Reumatoide/diagnóstico por imagen , Artritis Reumatoide/tratamiento farmacológico , Estudios de Cohortes , Humanos , Japón , Inducción de Remisión , Resultado del Tratamiento , UltrasonografíaRESUMEN
Objective: To determine whether the positivity of baseline anti-Ro/Sjögren's syndrome antigen A (SSA) antibodies influences the response to abatacept, we compared therapeutic responses between anti-Ro/SSA antibody-negative and -positive patients with rheumatoid arthritis (RA) using a multicentre RA ultrasonography prospective cohort. Method: We reviewed Japanese patients with RA who started abatacept as the first biological disease-modifying anti-rheumatic drug between June 2013 and April 2018. We assessed 28-joint Disease Activity Score-erythrocyte sedimentation rate (DAS28-ESR) change between baseline and 6 or 12 months after treatment in RA patients treated with abatacept, and European League Against Rheumatism (EULAR) response at 6 and 12 months. The Global OMERACT-EULAR Synovitis Score (GLOESS) was calculated at baseline and at 6 and 12 months. Results: Overall, 51 patients were enrolled and divided into anti-Ro/SSA antibody-negative and -positive groups of 35 and 16, respectively. Median age at baseline was significantly higher in the anti-Ro/SSA antibody-negative group (p = 0.04). The retention rate and percentage of EULAR good responders at 12 months were significantly higher in the anti-Ro/SSA antibody-negative group (both p = 0.02). Anti-Ro/SSA antibody-negative patients exhibited larger decreases in both DAS28-ESR and DAS28-C-reactive protein at 12 months than anti-Ro/SSA antibody-positive patients (p = 0.02 and 0.04, respectively). GLOESS decreased significantly at 6 months in anti-Ro/SSA antibody-negative patients (p = 0.03). Multivariate analyses showed that anti-Ro/SSA antibody positivity was an independent factor associated with change in the DAS28-ESR at 6 months (p < 0.05). Conclusion: Anti-Ro/SSA antibody positivity predicts a poor response to abatacept and low retention rate.
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Abatacept/uso terapéutico , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Autoantígenos/inmunología , ARN Citoplasmático Pequeño/inmunología , Ribonucleoproteínas/inmunología , Anciano , Artritis Reumatoide/inmunología , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Objective: Successful rheumatoid arthritis (RA) outcome depends on treatment efficacy in the early stages of the disease and its sustainability. It is thus critical to identify factors predicting treatment persistence with biological agents, such as abatacept. We compared clinical profiles, including early changes in autoantibody titres at 3 months, between patients with RA demonstrating sustained persistence and those discontinuing abatacept treatment.Method: We prospectively enrolled 71 and 78 active RA patients treated with abatacept and tumour necrosis factor inhibitors (TNF-Is), respectively, who had previous disease-modifying anti-rheumatic drug) failure. Clinical characteristics were compared between non-continuation and continuation groups stratified according to abatacept or TNF-I persistence for at least 12 months from treatment initiation.Results: Significantly larger decreases in rheumatoid factor titre and anti-citrullinated protein autoantibody (ACPA) titre were observed in the continuation group of abatacept therapy at 3 months, and early reduction in ACPA titre remained a significant and independent predictor of sustained persistence with abatacept in multivariate analysis. In addition, we obtained the area under the receiver operator characteristics curve of 0.904 from a model including baseline ACPA titre and reduction of ACPA titre at 3 months. Sustained reduction of RA disease activity score at 12 months was significantly and independently associated with reduced ACPA titre at 3 months.Conclusions: Persistence with abatacept and sustained therapeutic response are associated with an early reduction in ACPA titre. Prediction of abatacept continuation and efficacy will facilitate the optimal design of therapy in the early stages of RA.
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Abatacept/administración & dosificación , Anticuerpos Antiproteína Citrulinada/sangre , Artritis Reumatoide/inmunología , Anciano , Anticuerpos Antiproteína Citrulinada/inmunología , Antirreumáticos/administración & dosificación , Artritis Reumatoide/diagnóstico , Artritis Reumatoide/tratamiento farmacológico , Biomarcadores/sangre , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Humanos , Infusiones Intravenosas , Inyecciones Subcutáneas , Japón , Masculino , Estudios Prospectivos , Resultado del Tratamiento , UltrasonografíaRESUMEN
BACKGROUND: Activation of the Notch pathway has been reported in various types of cancers. However, the role of the hairy/enhancer-of-split related with YRPW motif protein 1 (HEY1) in osteosarcoma is unknown. We examined the function of HEY1 in osteosarcoma. METHODS: Expression of HEY1 was studied in human osteosarcoma. The effects of HEY1 in osteosarcoma were evaluated in vitro and in a xenograft model. Moreover, we examined the function of matrix metallopeptidase 9 (MMP9) as a downstream effector of HEY1. RESULTS: HEY1 was upregulated in human osteosarcoma. Knockdown of HEY1 inhibited the invasion of osteosarcoma cell lines. In contrast, the forced expression of HEY1 increased the invasion of mesenchymal stem cell. In addition, lung metastases were significantly inhibited by the knockdown of HEY1. We found that MMP9 was a downstream effector of HEY1 that promotes the invasion of osteosarcoma cells. Knockdown of HEY1 decreased the expression of MMP9. Addition of MMP9 rescued the invasion of osteosarcoma cells that had been rendered less invasive by knockdown of HEY1 expression. CONCLUSIONS: Our findings suggested that HEY1 augmented the metastasis of osteosarcoma via upregulation of MMP9 expression. Therefore, inhibition of HEY1 may be a novel therapeutic strategy for preventing osteosarcoma metastasis.
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Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Proteínas de Ciclo Celular/metabolismo , Metaloproteinasa 9 de la Matriz/biosíntesis , Osteosarcoma/metabolismo , Osteosarcoma/patología , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Neoplasias Óseas/enzimología , Neoplasias Óseas/genética , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Técnicas de Silenciamiento del Gen , Xenoinjertos , Humanos , Neoplasias Pulmonares/enzimología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundario , Metaloproteinasa 9 de la Matriz/genética , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/patología , Ratones , Ratones Desnudos , Metástasis de la Neoplasia , Osteosarcoma/enzimología , Osteosarcoma/genética , Transducción de Señal , Transfección , Regulación hacia ArribaRESUMEN
Electronic transport was investigated in poly(3-hexylthiophene-2,5-diyl) monolayers. At low temperatures, nonlinear behavior was observed in the current-voltage characteristics, and a nonzero threshold voltage appeared that increased with decreasing temperature. The current-voltage characteristics could be best fitted using a power law. These results suggest that the nonlinear conductivity can be explained using a Coulomb blockade (CB) mechanism. A model is proposed in which an isotropic extended charge state exists, as predicted by quantum calculations, and percolative charge transport occurs within an array of small conductive islands. Using quantitatively evaluated capacitance values for the islands, this model was found to be capable of explaining the observed experimental data. It is, therefore, suggested that percolative charge transport based on the CB effect is a significant factor giving rise to nonlinear conductivity in organic materials.
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We have demonstrated a direct frequency comparison between two 87Sr lattice clocks operated in intercontinentally separated laboratories in real time. Two-way satellite time and frequency transfer technique, based on the carrier-phase, was employed for a direct comparison, with a baseline of 9000 km between Japan and Germany. A frequency comparison was achieved for 83,640 s, resulting in a fractional difference of (1.1±1.6)×10⻹5, where the statistical part is the largest contributor to the uncertainty. This measurement directly confirms the agreement of the two optical frequency standards on an intercontinental scale.
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BACKGROUND: Meticillin-resistant Staphylococcus aureus (MRSA) is the most common pathogen in orthopaedic surgical site infections (SSIs). However, few studies have investigated the transmission process of orthopaedic MRSA SSI. AIM: To investigate the transmission process of orthopaedic MRSA SSI using epidemiological and molecular analyses and to determine a method to prevent MRSA SSI in nosocomial orthopaedic surgery. METHODS: Active MRSA surveillance, preoperative decolonization and contact precautions for MRSA-positive cases was performed at our institution. Changes in epidemic strains were evaluated and the possibility of transmission from patients in an orthopaedic ward of a Japanese tertiary-care hospital was assessed by genotyping stored MRSA strains. In addition, data on the prevalence of MRSA SSI, MRSA colonization, and use of an alcohol antiseptic agent (mL/patient-days) during 2005-2022 were retrospectively assessed. FINDINGS: SCCmec type II strain in the SSI group decreased over time, associated with fewer outbreaks. Even during a period of high infection rates, no cases of transmission-induced SSI from nasal MRSA carriers were identified. The infection rate correlated negatively with the use of an alcohol antiseptic agent (r = -0.82; P < 0.0001). Two cases among five nasal carriers developed MRSA SSI caused by strains different from those related to nasal colonization. CONCLUSION: The infection control measures for transmission from the hospital reservoirs including strict adherence to hand hygiene and decolonization of carriers is likely to be important for the prevention of orthopaedic MRSA SSI. However, the need for contact precautions for decolonized nasal carriers might be low.
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Snow depth is one of the most important determinants of vegetation, especially in mountainous regions. In such regions, snow depth tends to be low at wind-exposed sites such as ridges, where stand height and productivity are limited by stressful environmental conditions during winter. Siberian dwarf pine (Pinus pumila Regel) is a dominant species in mountainous regions of Japan. We hypothesized that P. pumila produces needles with greater mass per area at wind-exposed sites than at wind-protected sites because it invests more nitrogen (N) in cell walls at the expense of N investment in the photosynthetic apparatus, resulting in increased photosynthetic N use efficiency (PNUE). Contrary to our hypothesis, plants at wind-exposed site invested less resources in needles, as exhibited by lower biomass, N, Rubisco and cell wall mass per unit area, and had higher photosynthetic capacity, higher PNUE and shorter needle life-span than plants at a wind-protected site. N partitioning was not significantly different between sites. These results suggest that P. pumila at wind-exposed sites produces needles at low cost with high productivity to compensate for a short leaf life-span, which may be imposed by wind stress when needles appear above the snow surface in winter.
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Pinus/anatomía & histología , Pinus/metabolismo , Hojas de la Planta/anatomía & histología , Hojas de la Planta/metabolismo , Viento , Modelos Biológicos , Nitrógeno/metabolismo , Fotosíntesis/fisiología , Pinus/crecimiento & desarrollo , Hojas de la Planta/crecimiento & desarrolloAsunto(s)
Antirreumáticos/uso terapéutico , Dermatomiositis/tratamiento farmacológico , Dermatomiositis/epidemiología , Enfermedades Pulmonares Intersticiales/tratamiento farmacológico , Enfermedades Pulmonares Intersticiales/epidemiología , Dermatomiositis/diagnóstico , Resistencia a Medicamentos/fisiología , Femenino , Humanos , Enfermedades Pulmonares Intersticiales/diagnóstico , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , PronósticoRESUMEN
PURPOSE: To compare cup-positioning accuracy in total hip arthroplasty (THA) with or without use of a Kirschner wire as a transverse-axis guide for pelvic alignment. METHODS: Records of 18 men and 73 women (mean age, 60 years) who underwent primary THA with (n=49) or without (n=42) use of a Kirschner wire as a transverse-axis guide for pelvic alignment were reviewed. A 2.4-mm Kirschner wire as a transversea-xis guide was inserted to the anterior superior iliac spine and was parallel to a line linking the left and right anterior superior iliac spine. The safe zone for cup positioning was defined as 30º to 50° abduction and 10º to 30º anteversion. Of the 5 operative surgeons, 2 were classified as experienced (total surgical volume >300) and 3 as inexperienced (total surgical volume of <50). The proportion of patients with the cup in the safe zone was compared in patients with or without use of the transverse-axis guide and in experienced and inexperienced surgeons. RESULTS: For inexperienced surgeons, the use of the transverse-axis guide significantly improved the proportion of patients with the cup in the safe zone from 90% to 100% for abduction, from 50% to 82.4% for anteversion, and from 40% to 82.4% for both. Patients with the cup inside or outside the safe zone were comparable in terms of body height, weight, BMI, subcutaneous fat thickness, incision length, and acetabular cup size. CONCLUSION: The use of the transverse-axis guide improved the accuracy of cup positioning by inexperienced surgeons.
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Artroplastia de Reemplazo de Cadera/métodos , Hilos Ortopédicos , Prótesis de Cadera , Acetábulo/cirugía , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Posicionamiento del Paciente , Rango del Movimiento Articular , Estudios RetrospectivosRESUMEN
Sphingolipid products such as ceramide (cer), sphingosine (sph), and sphingosine-1-phosphate (SPP) are implicated in the regulation of cell growth and apoptosis. We have recently shown that cer, sph, and SPP differentially modulate ionic events in cultured oligodendrocytes (OLGs). Cer but not sph or SPP inhibits the inward rectifier (I(Kir)) in OLGs. To further investigate the role of sphingolipid products in OLGs, we studied the effect of cer, sph, and SPP on OLG survival and on the regulation of mitogen-activated protein kinases (MAPKs). We found that cer, sph, and SPP differentially modulate OLG survival and activation of MAPK members. Cer causes OLG apoptosis, sph causes OLG lysis, and SPP does not affect OLG survival. Cer induces a preferential activation of p38alpha, whereas sph and SPP induce a preferential activation of extracellular signal-regulated kinase 2 (ERK2) in OLGs. In addition, the effect of cer on p38alpha activity is mimicked by the inhibition of I(Kir) with Ba(2+). In contrast, exposure to cer results in increased activity of ERK2 but not of p38alpha in astrocytes. Cer-induced OLG apoptosis is attenuated by a p38 inhibitor, SB203580, and by expression of a p38alpha dominant negative mutant. We conclude that p38alpha is the mediator in cer-induced OLG apoptosis and that cer-induced I(Kir) inhibition may contribute to the sustained activation of p38alpha in OLGs.
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Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Proteínas Quinasas Activadas por Mitógenos , Oligodendroglía/fisiología , Esfingolípidos/fisiología , Animales , Animales Recién Nacidos , Apoptosis , Astrocitos/citología , Astrocitos/efectos de los fármacos , Astrocitos/fisiología , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Ceramidas/farmacología , Ceramidas/fisiología , Activación Enzimática/fisiología , Proteínas Quinasas JNK Activadas por Mitógenos , Proteína Quinasa 1 Activada por Mitógenos , Modelos Neurológicos , Oligodendroglía/citología , Oligodendroglía/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/metabolismo , Esfingolípidos/farmacología , Esfingosina/farmacología , Esfingosina/fisiología , Transfección , Proteínas Quinasas p38 Activadas por MitógenosRESUMEN
Reaction mechanisms of polyphenolic antioxidants were studied using electrochemical methods (flow column electrolysis and cyclic voltammetry). In flow column electrolysis, the numbers (ns) of electrons involved in the oxidation of catechols (chlorogenic acid and caffeic acid) became larger than two (i.e. the number of -OH moieties) at pH > 7; the n-values finally reached ca. 4 at pH 10. Other polyphenols including catechin, ellagic acid, and curcumin exhibited higher n-values than the numbers of -OH moieties in the whole pH range studied (4 < pH < 10). Such unusually large n-values for polyphenols were found to correlate to their irreversible behavior in cyclic voltammetry. A digital simulation analysis of the voltammograms of chlorogenic acid clearly showed that the electrode reaction at higher pHs can be elucidated in terms of a quasi-reversible electron transfer followed by a chemical reaction and also suggested that the chemical reaction is of second order to the concentration of chlorogenic acid, i.e. a dimerization reaction. In a similar manner, polyphenolic antioxidants generally undergo certain chemical reactions on the occasion of their oxidation. As a result, some oxidizable, phenolic -OH moieties are reproduced in the polymeric products. The unusually large n-values of polyphenols and thus their higher radical scavenging activities may be ascribed to such reproduction of -OH moieties by oxidative polymerization.
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Antioxidantes/química , Ácido Clorogénico/química , Catequina/química , Curcumina/química , Electrodos , Electrólisis , Electrones , Ácido Elágico/química , Concentración de Iones de Hidrógeno , Modelos Químicos , Oxidación-Reducción , PolímerosRESUMEN
About 500 second and 500 third chromosomes were extracted, using the marked inversion technique, from the Orlando-Lake Placid, Florida, population. From the experiments using these chromosomes, the following findings were obtained: (1) The frequencies of lethal-carrying chromosomes were 0.37 in the second and 0.55 in the third chromosomes. (2) The size of the population was estimated to be effectively infinite, on the basis of the allelism rate of lethal-carrying chromosomes. (3) The detrimental and lethal loads for viability were, respectively, 0.40 and 0.45 for the second and 0.52 and 0.78 for the third chromosomes. Consequently, the detrimental to lethal load ratio is 0.90 for the second and 0.67 for the third chromosomes. (4) Lethal genes were shown to be deleterious when heterozygous. (5) The average degree of dominance for mildly deleterious genes (viability polygenes) was estimated to be nearly 0.5, although the confidence interval is large. (6) Additive (sigma( 2) (A)) and dominance (sigma(2) ( D)) variances of viability were estimated by using a partial diallel cross method. The results were (see PDF) and (see PDF) for the second chromosomes. (7) Environmental variances of viability were estimated. The result indicates that the heterozygotes are more homeostatic than the homozygotes. The most striking finding is that the additive variance is larger than expected on the classical hypothesis from the detrimental load. Several possible explanations for the discrepancy are offered. The most likely cause, we suggest, is genotype-environment interaction (diversifying selection) acting on viability polygenes. Overdominance is inconsistent with the low dominance variance, and frequency-dependent selection also appears unlikely as an explanation.
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Genetic factors seem to play a significant role in susceptibility to systemic lupus erythematosus (SLE). We previously described the amino acid polymorphism (Val14Met) within the IFN-gamma receptor 1 (IFN-gammaRI), and that the frequency of the Metl4 allele in SLE patients was significantly higher than that of the healthy control population [Tanaka et al. (1999) Immunogenetics 49, 266-271]. We also found an amino acid polymorphism (Gln64Arg) within IFN-gamma receptor 2 (IFN-gammaR2). Since the IFN-gamma receptor is a complex consisting of IFN-gammaR1 and IFN-gammaR2, we searched for the particular combination of two kinds of amino acid polymorphisms found within the IFN-gamma receptor which plays a prominent role in susceptibility to SLE. The greatest risk of the development of SLE was detected in the individuals who had the combination of IFNGR1 Met14/Val14 genotype and IFNGR2 Gln64/Gln64 genotype.
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Predisposición Genética a la Enfermedad , Lupus Eritematoso Sistémico/genética , Polimorfismo Genético , Receptores de Interferón/genética , Adolescente , Adulto , Anciano , Secuencia de Aminoácidos , Arginina/genética , Secuencia de Bases , Femenino , Frecuencia de los Genes , Glutamina/genética , Humanos , Lupus Eritematoso Sistémico/epidemiología , Masculino , Metionina/genética , Persona de Mediana Edad , Datos de Secuencia Molecular , Oportunidad Relativa , Polimorfismo Conformacional Retorcido-Simple , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Valina/genética , Receptor de Interferón gammaRESUMEN
It has been demonstrated that interferon-gamma (IFN-gamma) and interleukin-10 (IL-10) have various reverse effects on macrophages; however, the molecular mechanism of this difference has not been fully understood. In this study, we analyzed the binding activity of IL-10- and IFN-gamma-activated STAT molecules to two kinds of GAS-motif sequences. IL-10-activated STAT1 could bind to the GAS-motif sequence in the promoter region of the Fcgamma receptor, but not to that in the promoter region of the COX-2 gene, whereas IFN-gamma-activated STAT1 and STAT5 could bind to both sequences. IL-10 inhibited IFN-gamma-induced STAT activation without newly synthesized protein. We further demonstrated that aspirin, but not dexamethasone, suppressed IFN-gamma-induced STAT activation. Taken together, these results suggest that IL-10-activated STAT1 has a specificity in binding to the GAS-motif sequences, whereas IFN-gamma-activated STAT1 and STAT5 have a broader spectrum in binding to the GAS-motif sequences. This may explain the difference between IL-10 and IFN-gamma in biological activity, and the inhibitory effect of IL-10 on IFN-gamma activities.
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Proteínas de Unión al ADN/metabolismo , Interleucina-10/farmacología , Proteínas de la Leche , Monocitos/efectos de los fármacos , Transducción de Señal/fisiología , Transactivadores/metabolismo , Aspirina/farmacología , Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa/farmacología , Dexametasona/farmacología , Humanos , Interferón gamma/farmacología , Isoenzimas/biosíntesis , Isoenzimas/efectos de los fármacos , Proteínas de la Membrana , Monocitos/metabolismo , Prostaglandina-Endoperóxido Sintasas/biosíntesis , Prostaglandina-Endoperóxido Sintasas/efectos de los fármacos , Factor de Transcripción STAT1 , Factor de Transcripción STAT5 , Estimulación QuímicaRESUMEN
We previously reported that oleic acid (OA) rapidly increased apolipoprotein (apo) B secretion by suppressing early intracellular degradation of nascent apo B in Hep G2 cells and suggested that the suppression of apo B degradation is associated with triglyceride (TG) biosynthesis from OA. To determine whether the inhibition of apo B degradation is associated with increased TG synthesis or is a direct effect of OA, we examined the effect of another fatty acid, eicosapentoenoic acid (EPA), on apo B kinetics in Hep G2 cells, since it is well known to have hypolipidemic action in clinical studies. The incorporation of [3H]glycerol into cellular TG was stimulated five-fold when Hep G2 cells were incubated for 2 h with EPA or OA (0.4 or 0.8 mM-1.5% bovine serum albumin (BSA) complex). The incorporation of [14C]acetic acid into cellular cholesteryl ester (CE) was significantly decreased by EPA treatment, whereas OA did not affect CE synthesis. Similar effects of these fatty acids on cellular lipid synthesis were observed in long-term incubation (24 h). Apo B was linearly secreted into the medium during 3 h, and EPA and OA doubled the rate of secretion. In long-term (24 h) incubations, both fatty acids significantly increased the incorporation of [3H]leucine into secreted apo B radioactivity or the accumulation of apo B mass in the medium. Pulse-chase studies revealed that both EPA and OA reduced intracellular apo B degradation to a similar degree. The inhibition of apo B degradation was also observed when the cells were preincubated with either EPA or OA for 24 h. These results suggest that increased TG synthesis leads to suppression of intracellular apo B degradation, which is independent of the source of exogenous fatty acid.
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Apolipoproteínas B/metabolismo , Ácido Eicosapentaenoico/farmacología , Hígado/efectos de los fármacos , Hígado/metabolismo , Apolipoproteínas B/biosíntesis , Células Cultivadas , Ésteres del Colesterol/biosíntesis , Ésteres del Colesterol/metabolismo , Humanos , Hígado/citología , Ácido Oléico , Ácidos Oléicos/farmacología , Triglicéridos/biosíntesis , Triglicéridos/metabolismoRESUMEN
To determine whether small-sized low density lipoprotein (LDL) is associated with a high incidence of coronary heart disease in diabetic nephropathy, we measured the LDL particle size in non-insulin-dependent diabetes mellitus (NIDDM) patients with various degrees of albuminuria (n = 95) and age-, weight-matched non-diabetic control subjects (n = 31). The diabetic subjects were divided into three groups, normoalbuminuric, microalbuminuric and macroalbuminuric NIDDM, based on the amount of albuminuria. The average diameter of LDL particles was determined by non-denaturing polyacrylamide gradient (2-16%) gel electrophoresis. The plasma lipid and lipoprotein concentrations were comparable between the non-diabetic controls and normoalbuminuric NIDDM, whereas the plasma triglyceride, very-low-density lipoprotein (VLDL) or LDL concentration was significantly increased in diabetic nephropathy. The mean LDL particle size was significantly smaller in microalbuminuric NIDDM compared with the controls or normoalbuminuric NIDDM, and the LDL size was further decreased in macroalbuminuric NIDDM. The incidence of small LDL (diameter < 255 A) was remarkably increased in microalbuminuric (58%) and macroalbuminuric NIDDM (67%) compared to the control (13%) and normoalbuminuric NIDDM (27%). Corresponding to the decreased LDL size, the cholesterol content of the LDL was significantly depleted in NIDDM with nephropathy. The high prevalence of small LDL in diabetic nephropathy was also observed even when hypertriglyceridemic or hypertensive subjects were excluded from each group. The increment in triglyceride-rich lipoprotein (d < 1.006) after oral fat-loading was increased, and postheparin lipoprotein lipase activity was decreased significantly in diabetic nephropathy. These abnormalities were significantly associated with LDL particle size. Multivariate regression analysis revealed that the amount of albuminuria was closely associated with the average LDL particle size, and this association was independent of the plasma triglyceride level. Neither insulin resistance nor glycemic control was directly associated with LDL particle diameter. The present study indicates that LDL particles become smaller in diabetic nephropathy, and this may be associated primarily with abnormal triglyceride metabolism. However, in addition to hypertriglyceridemia, other metabolic abnormalities caused by diabetic nephropathy may also be involved in the pathogenesis of small LDL particles.
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Diabetes Mellitus Tipo 2/sangre , Nefropatías Diabéticas/sangre , Glicoproteínas , Lipoproteínas LDL/sangre , Anciano , Albuminuria/sangre , Apoproteínas/sangre , Glucemia , Índice de Masa Corporal , Proteínas Portadoras/metabolismo , Proteínas de Transferencia de Ésteres de Colesterol , Comorbilidad , Enfermedad Coronaria/epidemiología , Creatina/sangre , Grasas de la Dieta/farmacocinética , Femenino , Humanos , Hipertensión/epidemiología , Hipertrigliceridemia/epidemiología , Lípidos/sangre , Lipoproteínas LDL/química , Masculino , Persona de Mediana Edad , Análisis Multivariante , Tamaño de la Partícula , Factores de Riesgo , Triglicéridos/sangreRESUMEN
To define the role of the renal dopaminergic system in the pathogenesis of essential hypertension, urinary free dopamine excretion was examined in 23 normotensive subjects who had one or more first-degree relatives with essential hypertension, and also in 36 matched control subjects without any such family history. The group urinary dopamine excretion and urinary sodium excretion were not different. However, a significant urine dopamine-sodium relationship was apparent in the controls but not in the relatives due to relatively high dopamine output in those with lower sodium excretion. The two groups were similar as regards blood pressure (BP), plasma renin activity (PRA), prolactin and catecholamines. These findings demonstrate an alteration in the urine dopamine-sodium relationship in some normotensive subjects with genetic risk of hypertension.
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Dopamina/orina , Hipertensión/genética , Adulto , Presión Sanguínea , Catecolaminas/sangre , Humanos , Hipertensión/etiología , Hipertensión/orina , Masculino , Prolactina/sangre , Renina/sangre , Sodio/orinaRESUMEN
It has been reported that patients with essential hypertension have high plasma prolactin levels and suggested that reduced central dopaminergic activity may be a factor in the pathogenesis of essential hypertension. This study examines the influence of posture on plasma prolactin, plasma catecholamines, plasma renin activity, blood pressure and heart rate in 24 patients with borderline hypertension (age 19 +/- 1 years) and 20 normotensive subjects matched for age and body mass index. Supine plasma prolactin levels were similar in both groups [borderline hypertension, 11.3 +/- 0.7 ng/ml; normotensive, 10.7 +/- 0.8 ng/ml (mean +/- s.e.m.)] and no increase in plasma prolactin was observed after 10 min standing in both groups. Normotensive and borderline hypertensive subjects had similar values for supine and upright plasma renin activity and plasma norepinephrine. There were no significant correlations between supine plasma prolactin and supine blood pressure, supine plasma renin activity or plasma norepinephrine when data from both normotensive and borderline hypertensive subjects were combined. These results may provide indirect evidence against the occurrence of reduced central dopaminergic activity in borderline hypertension.
Asunto(s)
Epinefrina/sangre , Hipertensión/sangre , Norepinefrina/sangre , Prolactina/sangre , Renina/sangre , Adulto , Creatinina/sangre , Humanos , Masculino , Postura , Potasio/sangre , Descanso , Sodio/sangreRESUMEN
BACKGROUND: The influence of hepatitis C virus (HCV) infection has been discussed in kidney transplantation. Our case study focused on four points: the clinical course of an HCV-infected recipient; the pathogenesis of hepatic disorders in such a patient; interferon (IFN)-alpha therapy; and the risk of IFN-alpha therapy. METHOD: A patient was suspected of acquiring HCV via transfusion at kidney transplant. He was examined several times serologically, virologically, endoscopically, and pathologically during a 20-year follow-up. RESULTS: Abnormal biochemical markers were found within a month after transplantation but recovery occurred without any treatment. Within 3 years postoperatively, hepatic disorder developed including peliosis hepatis, nodular regenerative hyperplasia, and cholestasis. These pathological conditions were ascribed to immunosuppressants: cyclophosphamide and azathioprine. Abnormal chemical markers decreased to normal values for 4 consecutive years with the substitution of cyclophosphamide and azathioprine for mizoribine. During the subsequent 13 years, the patient developed chronic hepatitis with clinical and morphological features of hepatitis C infection. Anti-HCV antibody was positive from the second post-transplant year and HCV genome was detected in the 17th year. IFN-alpha therapy was initiated in the 17th year and resulted in normal transaminase activities with no effect on viremia. However, acute cellular rejection developed. The rejection was steroid resistant but responsive to OKT3. CONCLUSION: HCV might remain latent for approximately 7 years even in kidney recipients unless toxic hepatitis occurs. Hepatotoxic drugs may cause a wide spectrum of liver diseases in HCV carriers as a result of the overload of immunosuppressants on hepatocytes. IFN-alpha could induce acute cellular rejection even in the 17th year. Such acute rejection can be reversible with OKT3.