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1.
Phys Chem Chem Phys ; 21(3): 1587-1596, 2019 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-30620033

RESUMEN

The radiative cooling of highly excited carbon cluster cations of sizes N = 8, 10, 13-16 has been studied in an electrostatic storage ring. The cooling rate constants vary with cluster size from a maximum at N = 8 of 2.6 × 104 s-1 and a minimum at N = 13 of 4.4 × 103 s-1. The high rates indicate that photon emission takes place from electronically excited ions, providing a strong stabilizing cooling of the molecules.

2.
J Prev Alzheimers Dis ; 10(4): 810-820, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37874103

RESUMEN

INTRODUCTION: Lower blood levels of the omega-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) are correlated with worse cognitive functions, particularly among APOE ε4 carriers. Whether DHA supplementation in APOE ε4 carriers with limited DHA consumption and dementia risk factors can delay or slow down disease progression when started before the onset of clinical dementia is not known. METHODS: PreventE4 is a double-blind, single site, randomized, placebo-controlled trial in cognitively unimpaired individuals with limited omega-3 consumption and dementia risk factors (n=368). Its objectives are to determine (1) whether carrying the APOE ε4 allele is associated with lower delivery of DHA to the brain; and (2) whether high dose DHA supplementation affects brain imaging biomarkers of AD and cognitive function. RESULTS: 365 cognitively unimpaired individuals between 55 and 80 (mean age 66) were randomized to 2 grams of DHA per day or identically appearing placebo for a period of 2 years. Half the participants were asked to complete lumbar punctures at baseline and 6-month visits to obtain cerebrospinal fluid (CSF). The primary trial outcome measure is the change in CSF DHA to arachidonic acid ratio after 6 months of the intervention (n=181). Secondary trial outcomes include the change in functional and structural connectivity using resting state functional MRI at 24 months (n=365). Exploratory outcomes include the change in Repeatable Battery of the Assessment of Neuropsychological Status at 24 months (n=365). CONCLUSIONS: Findings from PreventE4 will clarify the brain delivery of DHA in individuals carrying the APOE ε4 allele with implications for dementia prevention strategies. Trial was registered as NCT03613844.


Asunto(s)
Enfermedad de Alzheimer , Ácidos Grasos Omega-3 , Humanos , Enfermedad de Alzheimer/tratamiento farmacológico , Apolipoproteína E4/genética , Encéfalo/diagnóstico por imagen , Ácidos Docosahexaenoicos/uso terapéutico , Ácidos Grasos Omega-3/uso terapéutico , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años
3.
Rechtsmedizin (Berl) ; 32(1): 47-51, 2022.
Artículo en Alemán | MEDLINE | ID: mdl-33907354

RESUMEN

Coronary artery autoimmune vasculitis (Kawasaki syndrome) is at least in Germany a very rare condition, that typically manifests in childhood. The symptoms are often unspecific and complications with vascular aneurysms, thrombosis and myocardial infarction can occur. Multiple cases of Kawasaki-like symptoms in children with positive SARS-CoV­2 test results have been reported during the course of the COVID-19 pandemic the past year.This case study reports on a 2-year-old child who had fever over 6 days and after a temporary improvement, died within 1 day (pre-COVID19 era).The autopsy showed autoimmune vasculitis of the right and left main coronary artery consistent with Kawasaki syndrome with aneurysm formation, acute thrombosis and myocardial infarction.In the case of macroscopically conspicuous dilated and/or thrombosed coronary arteries and/or myocardial infarction in children, a Kawasaki syndrome should be excluded in addition to other differential diagnoses.

4.
Sci Rep ; 11(1): 4613, 2021 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-33633289

RESUMEN

Extracellular vesicles (EVs) are well-known mediators in intercellular communication playing pivotal roles in promoting liver inflammation and fibrosis, events associated to hepatic lipotoxicity caused by saturated free fatty acid overloading. However, despite the importance of lipids in EV membrane architecture which, in turn, affects EV biophysical and biological properties, little is known about the lipid asset of EVs released under these conditions. Here, we analyzed phospholipid profile alterations of EVs released by hepatocarcinoma Huh-7 cells under increased membrane lipid saturation induced by supplementation with saturated fatty acid palmitate or Δ9 desaturase inhibition, using oleate, a nontoxic monounsaturated fatty acid, as control. As an increase of membrane lipid saturation induces endoplasmic reticulum (ER) stress, we also analyzed phospholipid rearrangements in EVs released by Huh-7 cells treated with thapsigargin, a conventional ER stress inducer. Results demonstrate that lipotoxic and/or ER stress conditions induced rearrangements not only into cell membrane phospholipids but also into the released EVs. Thus, cell membrane saturation level and/or ER stress are crucial to determine which lipids are discarded via EVs and EV lipid cargos might be useful to discriminate hepatic lipid overloading and ER stress.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Vesículas Extracelulares/metabolismo , Ácidos Grasos/efectos adversos , Neoplasias Hepáticas/metabolismo , Lípidos de la Membrana/metabolismo , Línea Celular Tumoral , Estrés del Retículo Endoplásmico/efectos de los fármacos , Vesículas Extracelulares/efectos de los fármacos , Humanos , Ácido Oléico/efectos adversos , Ácido Palmítico/efectos adversos
5.
J Exp Med ; 186(4): 613-8, 1997 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-9254659

RESUMEN

Insulin-dependent diabetes mellitus (IDDM) is assumed to be a T cell-mediated autoimmune disease. To investigate the role of Fas-mediated cytotoxicity in pancreatic beta cell destruction, we established nonobese diabetic (NOD)-lymphoproliferation (lpr)/lpr mice lacking Fas. Out of three genotypes, female NOD-+/+ and NOD-+/lpr developed spontaneous diabetes by the age of 10 mo with the incidence of 68 and 62%, respectively. In contrast, NOD-lpr/lpr did not develop diabetes or insulitis. To further explore the role of Fas, adoptive transfer experiments were performed. When splenocytes were transferred from diabetic NOD, male NOD-+/+ and NOD-+/lpr developed diabetes with the incidence of 89 and 83%, respectively, whereas NOD-lpr/lpr did not show glycosuria by 12 wk after transfer. Severe mononuclear cell infiltration was revealed in islets of NOD-+/+ and NOD-+/lpr, whereas islet morphology remained intact in NOD-lpr/lpr. These results suggest that Fas-mediated cytotoxicity is required to initiate beta cell autoimmunity in NOD mice. Fas-Fas ligand system might be critical for autoimmune beta cell destruction leading to IDDM.


Asunto(s)
Diabetes Mellitus Tipo 1/etiología , Receptor fas/fisiología , Traslado Adoptivo , Animales , Femenino , Genotipo , Masculino , Ratones , Ratones Endogámicos NOD , Repeticiones de Microsatélite , Fenotipo , Linfocitos T/fisiología
6.
Bone Joint J ; 100-B(12): 1585-1591, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30499324

RESUMEN

AIMS: Patellofemoral problems are a common complication of total knee arthroplasty. A high compressive force across the patellofemoral joint may affect patient-reported outcome. However, the relationship between patient-reported outcome and the intraoperative patellofemoral contact force has not been investigated. The purpose of this study was to determine whether or not a high intraoperative patellofemoral compressive force affects patient-reported outcome. PATIENTS AND METHODS: This prospective study included 42 patients (42 knees) with varus-type osteoarthritis who underwent a bi-cruciate stabilized total knee arthroplasty and in whom the planned alignment was confirmed on 3D CT. Of the 42 patients, 36 were women and six were men. Their mean age was 72.3 years (61 to 87) and their mean body mass index (BMI) was 24.4 kg/m 2 (18.2 to 34.3). After implantation of the femoral and tibial components, the compressive force across the patellofemoral joint was measured at 10°, 30°, 60°, 90°, 120°, and 140° of flexion using a load cell (Kyowa Electronic Instruments Co., Ltd., Tokyo, Japan) manufactured in the same shape as the patellar implant. Multiple regression analyses were conducted to investigate the relationship between intraoperative patellofemoral compressive force and patient-reported outcome two years after implantation. RESULTS: No patient had anterior knee pain after total knee arthroplasty. The compressive force across the patellofemoral joint at 140°of flexion was negatively correlated with patient satisfaction (R 2 = 0.458; ß = -0.706; p = 0. 041) and Forgotten Joint Score-12 (FJS-12; R 2 = .378; ß = -0.636; p = 0. 036). The compressive force across the patellofemoral joint at 60° of flexion was negatively correlated with the patella score (R 2 = 0.417; ß = -0.688; p = 0. 046). CONCLUSION: Patient satisfaction, FJS-12, and patella score were affected by the patellofemoral compressive force at 60° and 140° of flexion. Reduction of the patellofemoral compressive forces at 60° and 140° of flexion angle during total knee arthroplasty may improve patient-reported outcome, but has no effect on anterior knee pain.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/métodos , Prótesis de la Rodilla , Articulación Patelofemoral/fisiopatología , Medición de Resultados Informados por el Paciente , Tibia/fisiopatología , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Femenino , Fémur/fisiopatología , Fémur/cirugía , Estudios de Seguimiento , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/cirugía , Articulación Patelofemoral/diagnóstico por imagen , Articulación Patelofemoral/cirugía , Presión , Estudios Prospectivos , Rango del Movimiento Articular , Tibia/cirugía , Tomografía Computarizada por Rayos X
7.
J Clin Invest ; 76(2): 556-60, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3861621

RESUMEN

To investigate purine catabolism in exercising muscles of patients with muscle glycogen storage disease, we performed ischemic forearm exercise tests and quantitated metabolites appearing in cubital venous blood. Two patients with glycogen storage disease type V and three with glycogen storage disease type VII participated in this study. Basal lactate concentrations lowered in every patient with glycogen storage disease type V or type VII. Two patients with glycogen storage disease type VII, who had markedly elevated concentrations of serum uric acid (14.3 and 11.9 mg/dl, respectively), showed high basal concentrations of ammonia (118 and 79 mumol/liter, respectively; 23 +/- 4 mumol/liter in healthy controls) and of hypoxanthine (23.4 and 20.4 mumol/liter, respectively; 2.0 +/- 0.4 mumol/liter in healthy controls). Other patients showed near normal measurements of these metabolites. After forearm exercise, ammonia, inosine, and hypoxanthine levels increased greatly in every patient studied, in contrast with the lack of increase in lactate levels. The incremental area under the concentration curves for venous ammonia was 13-fold greater in the glycogen storage disease group than in controls (1,120 +/- 182 vs. 83 +/- 26 mumol X min/liter). The incremental areas of inosine and hypoxanthine were also greater in the glycogen storage disease group (29.2 +/- 7.2 vs. 0.4 +/- 0.1 and 134.6 +/- 23.1 vs. 14.9 +/- 3.2 mumol X min/liter, respectively). The incremental areas of ammonia in controls and in glycogen storage disease patients strongly correlated with those of hypoxanthine (r = 0.984, n = 11, P less than 0.005). These findings indicated that excess purine degradation occurred in the exercising muscles of patients with glycogen storage disease types V and VII, and suggested that the ATP pool in the exercising muscles may be deranged because of defective glycogenolysis or glycolysis.


Asunto(s)
Enfermedad del Almacenamiento de Glucógeno Tipo VII/metabolismo , Enfermedad del Almacenamiento de Glucógeno Tipo V/metabolismo , Enfermedad del Almacenamiento de Glucógeno/metabolismo , Músculos/metabolismo , Esfuerzo Físico , Purinas/metabolismo , Adulto , Amoníaco/sangre , Femenino , Glucólisis , Humanos , Hipoxantina , Hipoxantinas/sangre , Inosina/sangre , Lactatos/sangre , Ácido Láctico , Masculino , Modelos Biológicos , Músculos/irrigación sanguínea , Ácido Úrico/sangre
8.
Int J HIV AIDS Res ; 4(3): 154-160, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29577081

RESUMEN

BACKGROUND: Clinical response to highly active antiretroviral therapy (HAART) varies among different populations. A portion of this variability may be due to variation in genes involved in the absorption, distribution, metabolism, and excretion (ADME) of HAART. DESIGN: To identify genetic factors involved in virologic responses to HAART, 13 genes in ADME pathways were analyzed in a cohort of HIV-infected women on HAART. A total of 569 HIV-positive participants from the Women's Interagency HIV Study who initiated HAART from 1994-2012 and had genotype data were included in these analyses. METHODS: Admixture maximum likelihood burden testing was used to evaluate gene-level associations between common genetic variation and virologic response (achieving <80 viral copies/mL) to HAART overall and with specific drug classes. Results: Six statistically significant (P<0.05) gene-level burden tests were observed with response to specific regimen types. CYP2B6, CYP2C19 and CYP2C9 were significantly associated with response to protease inhibitor (PI)-based regimens. CYP2C9, ADH1A and UGT1A1 were significantly associated with response to triple nucleoside reverse transcriptase inhibitor (NRTI) treatment. CONCLUSIONS: Although no genome-wide associations with virologic response to HAART overall were detected in this cohort of HIV-infected women, more statistically significant gene-level burden tests were observed than would be expected by chance (two and a half expected, six observed). It is likely that variation in one of the significant genes is associated with virologic response to certain HAART regimens. Further characterization of the genes associated with response to PI-based treatment is warranted.

9.
J Orthop Surg (Hong Kong) ; 24(1): 16-21, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-27122506

RESUMEN

PURPOSE: To compare bone mineral density (BMD) in patients with or without weekly injection of teriparatide to promote bone ingrowth after cementless total knee arthroplasty (TKA). METHODS: Records of 8 men and 32 women (mean age, 75.6 years) who underwent cementless TKA for medial knee osteoarthritis with (n=20) or without (n=20) once-weekly subcutaneous/hypodermic injection of teriparatide for 48 weeks were reviewed. BMD and bone volume/total volume (BV/TV) of the bone-prosthesis interface of the proximal tibia in 6 regions of interest (ROI) were assessed at 3, 6, 9, and 12 months using multi-detector computed tomography. RESULTS: Patients with or without weekly injection of teriparatide after cementless TKA were comparable in terms of baseline characteristics and pre- and post-operative knee range of motion and Knee Society knee and function scores. In ROI 1 (medial), ROI 3 (anteromedial), and ROI 4 (posteromedial), the BV/TV increased throughout the postoperative period in patients with weekly injection of teriparatide and declined after 6 months in patients without weekly injection of teriparatide. These 3 ROIs of the 2 groups differed significantly only in BMD at 6, 9, and 12 months. In ROI 2 (lateral), ROI 5 (anterolateral), and ROI 6 (posterolateral), both BV/TV and BMD showed a decreasing trend, and these 3 ROIs of the 2 groups did not differ significantly. CONCLUSION: Weekly injection of teriparatide after cementless TKA promoted bone ingrowth mostly in the medial aspect of the bone-prosthesis interface.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Conservadores de la Densidad Ósea/administración & dosificación , Densidad Ósea , Osteoartritis de la Rodilla/cirugía , Teriparatido/administración & dosificación , Anciano , Anciano de 80 o más Años , Esquema de Medicación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
10.
Biochim Biophys Acta ; 993(1): 128-30, 1989 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-2804119

RESUMEN

Bilirubin-IX beta isomer was detected in the bile of eel, Anguilla japonica, as evidenced by high-performance liquid chromatography (HPLC) analysis of free acid and its ethyl anthranilate diazo derivatives. Bilirubin-IX beta accounted for 16.7 +/- 6.0 (mean +/- S.D.) percent of the total bilirubins in the bile of 40 eels analysed, and the percentage was much higher than that reported in the biles of mammals.


Asunto(s)
Anguilla/metabolismo , Bilis/análisis , Bilirrubina/análisis , Animales , Cromatografía Líquida de Alta Presión
11.
Biochim Biophys Acta ; 1289(1): 145-9, 1996 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-8605225

RESUMEN

Expression of key regulatory enzymes involved in glucose metabolism was studied in the livers of Otsuka Long-Evans Tokushima fatty (OLETF) rats, a model of non-insulin dependent diabetes mellitus. The activity and mRNA levels of glucokinase and L-type pyruvate kinase was increased in the liver of OLETF rats compared with control rats. There was no such remarkable change in liver-type phosphofructokinase. The activities of glucose-6-phosphatase and fructose-1,6-biphosphatase also increase despite high plasma levels of glucose and insulin. The activity of phosphoenolpyruvate carboxykinase did not show any significant change. The mRNA levels for fructose-1,6-biphosphatase, and phosphoenolpyruvate carboxykinase exhibited no marked changes. These results suggest that the expression of glucose-6-phosphatase and fructose-1,6-biphosphatase is disordered in OLETF rats.


Asunto(s)
Diabetes Mellitus Tipo 2/metabolismo , Gluconeogénesis , Glucólisis , Hiperglucemia/metabolismo , Hígado/enzimología , Animales , Regulación Enzimológica de la Expresión Génica , Glucoquinasa/genética , Masculino , Fosfofructoquinasa-1/genética , ARN Mensajero/análisis , Ratas
12.
Biochim Biophys Acta ; 1289(1): 131-5, 1996 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-8605222

RESUMEN

We conducted a quantitative study of the effect of carnitine deficiency on the mRNA level of carnitine palmitoyltransferase II in the liver, muscle and heart of mice with juvenile visceral steatosis, a strain that is systematically deficient in carnitine. The amount of carnitine palmitoyltransferase II mRNA was increased in liver and muscle of homozygotes, as compared with heterozygotes and normal controls, at 2, 4, and 8 wk of age. The mRNA levels of this enzyme were normalized after carnitine administration. The mRNA level of carnitine palmitoyltransferase II in the heart was increased only at 8 wk, and was not affected by carnitine administration. These results suggest that carnitine displays some effect on the mRNA level of the carnitine palmitoyltransferase II gene in liver and muscle, probably through fatty acid metabolic change.


Asunto(s)
Carnitina O-Palmitoiltransferasa/genética , Hígado Graso/enzimología , Regulación Enzimológica de la Expresión Génica , Hipoglucemia/enzimología , Hígado/enzimología , Músculos/enzimología , Miocardio/enzimología , Amoníaco/sangre , Animales , Ratones , Ratones Endogámicos C3H , ARN Mensajero/análisis
13.
Diabetes ; 30(4): 346-53, 1981 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6451463

RESUMEN

The concentrations of glycolytic intermediates and adenine nucleotides were determined in erythrocytes from patients with diabetic ketoacidosis before and during insulin treatment. Ketoacidosis resulted in an increase in the levels of intermediates above the phosphofructokinase (PFK) step and a marked decrease in the levels of those below this step. Thus, a "crossover" point was seen at the PFK step in a crossover plot. This indicated that the rate of glycolytic flow during ketoacidosis was controlled by PFK and that the reduced level of 2,3-bisphosphoglycerate (2, 3-BPG) was attributed to the inhibition of this enzyme. In vitro studies revealed that acidemia is mainly responsible for the inhibition of PFK, whereas elevated levels of ketone bodies and free fatty acids have no direct bearing on it. Insulin administration produced hypophosphatemia within 8-12 h and it persisted for 24 h or longer. The levels of fructose-6-phosphate and glucose-6-phosphate were decreased transiently during this hypophosphatemic phase, while those of fructose bisphosphate and triose phosphates were increased. This indicated that PFK was activated. Thus, it is no longer reasonable to think that the inhibition of PFK is a factor responsible for a delay in normalization of the 2, 3-BPG level during the recovery phase. The levels of these glycolytic intermediates, including 2, 3-BPG, were normalized within 4 days by appropriate therapy.


Asunto(s)
Cetoacidosis Diabética/sangre , Eritrocitos/metabolismo , Adulto , Anciano , Diabetes Mellitus/tratamiento farmacológico , Ácidos Difosfoglicéricos/sangre , Femenino , Glucólisis , Humanos , Insulina/uso terapéutico , Masculino , Persona de Mediana Edad , Fosfatos/sangre , Fosfofructoquinasa-1
14.
Diabetes ; 38(7): 902-5, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2661287

RESUMEN

We examined the effect of glucagonlike peptides (GLPs), which are cleaved from preproglucagon in the enteroglucagon cells, on rat endocrine pancreas with the isolated perfused system. GLP-I-(7-36)-amide, a truncated form of full-sequence GLP-I-(1-37), showed a potent inhibitory effect on glucagon secretion. This inhibitory effect of GLP-I-(7-36)-amide was demonstrated at concentrations of 0.25, 2.5, and 25 nM in 11.2 and 2.8 mM glucose. In contrast, insulin release was significantly stimulated by GLP-I-(7-36)-amide at its concentration from 0.025 to 25 nM in a high glucose concentration, whereas in a low glucose concentration, the stimulation was seen only at the highest concentration (25 nM). Neither GLP-I-(1-37) nor GLP-II showed any effect on glucagon and insulin release. Although several gastrointestinal hormones have been nominated as incretins, none of them may suppress the glucagon secretion. A truncated form of GLP-I, GLP-I-(7-36)-amide thus seems to be a unique incretin that exerts glucagonostatic action.


Asunto(s)
Glucagón/metabolismo , Insulina/metabolismo , Páncreas/metabolismo , Fragmentos de Péptidos , Péptidos/farmacología , Animales , Péptido 1 Similar al Glucagón , Péptidos Similares al Glucagón , Glucosa/farmacología , Masculino , Páncreas/efectos de los fármacos , Ratas , Ratas Endogámicas
15.
Diabetes ; 37(2): 204-8, 1988 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3292315

RESUMEN

To clarify the pathogenesis of insulitis in the nonobese diabetic (NOD) mouse, an animal model for human insulin-dependent diabetes mellitus, T-lymphocyte-depleted NOD mice (B mice) were adoptively transferred with spleen and lymph node cells from cyclophosphamide-treated NOD mice after separating the cells with monoclonal antibodies against various T-lymphocyte surface antigens plus complement. Light-microscopic and immunohistochemical studies were also performed to investigate the lymphocytic infiltrations. The incidence of insulitis detected in B mice was much lower when compared with that of the lesion naturally occurring in the NOD mouse. However, higher incidence of insulitis was inducible in B mice by transferring unfractionated lymphoid cells from NOD mice. When the Thy1+ cell-depleted fraction was transferred into the B mice, no increase in the incidence of insulitis was observed. The Lyt1+ or L3T4+ cell-eliminated fraction was also unable to transfer insulitis. Conversely, donor cells depleted of Lyt2+ components successfully induced insulitis in the recipient B mice. These data were consistent with the immunohistochemical study, which showed that the main phenotype of the cells infiltrating the islets was L3T4+. These results suggest the importance of L3T4+Lyt2- T-lymphocytes in the pathogenesis of insulitis in NOD mice.


Asunto(s)
Diabetes Mellitus Tipo 1/complicaciones , Inmunización Pasiva , Islotes Pancreáticos , Linfocitos T/trasplante , Animales , Enfermedades Autoinmunes/etiología , Diabetes Mellitus/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patología , Femenino , Inmunohistoquímica , Ganglios Linfáticos/citología , Ganglios Linfáticos/trasplante , Depleción Linfocítica , Masculino , Ratones , Ratones Mutantes , Obesidad , Enfermedades Pancreáticas/etiología , Bazo/citología , Bazo/trasplante , Linfocitos T/patología
16.
Diabetes ; 35(11): 1262-7, 1986 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3530854

RESUMEN

Islet cell surface antibodies (ICSAs) in sera of New Zealand Black (NZB) and New Zealand White (NZW) mice were detected by the indirect immunofluorescence method with cultured Balb/c mouse islet cells as antigens. Circulating ICSAs appeared in NZB mice from age 20 wk; at 30 wk, 73% of male mice and 88% of female mice had detectable ICSAs. The ICSAs were significantly absorbed with mouse islet cells but hardly absorbed with spleen cells or liver powder. The ICSAs also bound with islet cells of ICR mice, Sprague-Dawley rats, and NZB mice. NZB mice showed glucose intolerance especially at ages 10 and 30 wk. Although plasma glucose levels tended to be higher in NZB mice with strongly positive ICSAs, pancreatic insulin content was not reduced, and insulitis was rarely observed in the pancreases. On the other hand, 30-wk-old NZW mice had normal or mildly impaired glucose tolerance and only weak, if any, ICSAs. The ICSA-positive serum of NZB mice significantly suppressed glucose-induced insulin release by cultured islet cells. The ICSAs may be responsible, at least in part, for glucose intolerance in NZB mice after age 20 wk through the inhibitory effect on insulin secretion.


Asunto(s)
Antígenos de Superficie/inmunología , Insulina/metabolismo , Islotes Pancreáticos/inmunología , Factores de Edad , Animales , Anticuerpos/inmunología , Células Cultivadas , Femenino , Prueba de Tolerancia a la Glucosa , Secreción de Insulina , Masculino , Ratones , Ratones Endogámicos BALB C
17.
Endocrinology ; 128(3): 1409-13, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1900229

RESUMEN

The effects of interferon-gamma (IFN gamma) on the morphology of thyroid follicles and the expression of major histocompatibility complex (MHC) class II antigens were examined. The thyroid follicles were suspended in RPMI-1640 containing 10% fetal calf serum with or without IFN gamma (200 U/ml). After culture for 5 days, follicles were incubated in the presence of TSH (10 mU/ml) for 1 h and fixed for electron microscopic and immunohistochemical examination. Regardless of the presence of IFN gamma, suspended follicles became inverted within 5 days. However, MHC class II antigens were expressed only in inverted follicles cultured with IFN gamma. In inverted follicles cultured without IFN gamma, TSH stimulation induced remarkable morphological changes, such as elongation of microvilli and an appearance of pseudopods. On the other hand, the follicles cultured with IFN gamma showed poor response to TSH. Thus, IFN gamma induced the expression of MHC class II antigens of cultured thyroid follicles and inhibited TSH-induced morphological changes in the cells.


Asunto(s)
Antígenos de Histocompatibilidad Clase II/análisis , Interferón gamma/farmacología , Glándula Tiroides/ultraestructura , Tirotropina/farmacología , Animales , Técnicas de Cultivo , Masculino , Ratones , Ratones Endogámicos C3H , Microscopía Electrónica de Rastreo , Suspensiones , Glándula Tiroides/inmunología
18.
J Clin Endocrinol Metab ; 74(3): 614-8, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1740495

RESUMEN

A considerable number of thyrocytes in patients with autoimmune thyroiditis ectopically express HLA-DR antigen. Furthermore, it has been reported that interferon-gamma-induced DR-positive thyrocytes in vitro secrete less thyroid hormone in response to TSH stimulation compared with DR-negative ones. However, the function of the intrinsically DR-positive thyrocytes is unknown. To evaluate their function, we stained by immunofluorescence for both DR antigen and thyroid peroxidase (TPO) in thyroid epithelial cells from patients with Graves' disease. We also measured the quantity of DR antigen and TPO using fluorescent photometry. The content of TPO was not significantly reduced in DR-positive thyrocytes compared with that in DR-negative thyrocytes. The TPO content is one measure of thyrocyte function. There was no significant difference between DR-positive and DR-negative thyrocytes. In conclusion, the function of DR-positive thyrocytes in vivo was not suppressed compared with that of DR-negative thyrocytes.


Asunto(s)
Enfermedad de Graves/enzimología , Enfermedad de Graves/inmunología , Antígenos HLA-DR/inmunología , Yoduro Peroxidasa/metabolismo , Glándula Tiroides/enzimología , Glándula Tiroides/inmunología , Adulto , Femenino , Técnica del Anticuerpo Fluorescente , Enfermedad de Graves/cirugía , Antígenos HLA-DR/análisis , Humanos , Inmunohistoquímica , Linfocitos/inmunología , Masculino
19.
J Clin Endocrinol Metab ; 74(6): 1331-5, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1592878

RESUMEN

To clarify the role of interferon-gamma (IFN gamma) in autoimmune thyroid diseases, we investigated the effects of IFN gamma on the content of thyroid peroxidase (TPO) and the expression of HLA-DR antigens in cultured normal human thyrocytes. The effect of TSH on the action of IFN gamma was investigated. Immunofluorescence staining and photometric analysis showed that IFN gamma not only induced the expression of DR antigen, but also reduced the content of TPO in a concentration-dependent manner. The addition of TSH increased the content of TPO and enhanced the IFN gamma-induced expression of DR antigen. IFN gamma also inhibited the increase in TPO content induced by TSH. Thus, complex interactions appear to exist between IFN gamma and TSH or thyroid-stimulating antibodies in the modulation of hormone secretion and autoimmune phenomena in the thyroid.


Asunto(s)
Interferón gamma/farmacología , Yoduro Peroxidasa/metabolismo , Glándula Tiroides/enzimología , Tirotropina/farmacología , Adenoma/enzimología , Adenoma/cirugía , Adulto , Células Cultivadas , Niño , Femenino , Técnica del Anticuerpo Fluorescente , Antígenos HLA-DR/análisis , Humanos , Cinética , Masculino , Persona de Mediana Edad , Proteínas Recombinantes , Glándula Tiroides/efectos de los fármacos , Glándula Tiroides/inmunología , Neoplasias de la Tiroides/enzimología , Neoplasias de la Tiroides/cirugía , Tiroidectomía , Tirotropina/antagonistas & inhibidores
20.
J Clin Endocrinol Metab ; 74(6): 1372-7, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1592883

RESUMEN

We investigated transthyretin (TTR) in the pancreases and sera of 10 newly diagnosed type I diabetic patients by immunohistochemistry and nephelometry. In the type I diabetic pancreases, glucagon-positive A-cells showed strong immunoreactivity for TTR, the intensity and distribution pattern of which corresponded to those in normal subjects. Morphometric analysis revealed that the amount of strongly TTR-positive A-cells was not significantly different from that in normal subjects. On the contrary, insulin-positive B-cells, which normally show uneven and weak TTR immunoreactivity, decreased in number, and only a few residual B-cells showed faint immunoreactivity. Neither somatostatin cells nor pancreatic polypeptide cells were positive for TTR. The serum TTR concentration showed a significant decrease in type I diabetic patients compared with that in normal subjects (P less than 0.005). These data suggest that the synthesis or storage of TTR in A-cells is not affected, but that in B-cells is impaired in type I diabetes. The decrease in serum TTR might be one of the features of metabolic disorders in type I diabetes.


Asunto(s)
Diabetes Mellitus Tipo 1/metabolismo , Páncreas/metabolismo , Prealbúmina/análisis , Adulto , Autoanticuerpos/análisis , Biopsia , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 1/patología , Femenino , Técnica del Anticuerpo Fluorescente , Antígenos de Histocompatibilidad Clase I/análisis , Antígenos de Histocompatibilidad Clase II/análisis , Humanos , Técnicas para Inmunoenzimas , Islotes Pancreáticos/inmunología , Masculino , Páncreas/patología , Linfocitos T/inmunología
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