Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 105
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Diabet Med ; 29(6): 767-70, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22211818

RESUMEN

AIMS: Although current American Heart Association guidelines address C-reactive protein concentration and cardiovascular disease risk, it remains unclear whether this paradigm is consistent across populations with differing disease burdens. Individuals with Type 2 diabetes mellitus represent one group at increased risk of cardiovascular disease and subsequent mortality. This study aimed to examine the relationship between C-reactive protein concentrations and risk for all-cause mortality in European Americans with Type 2 diabetes from the Diabetes Heart Study. METHODS: A total of 846 European Americans with Type 2 diabetes and baseline measures of C-reactive protein were evaluated. Vital status was determined after a follow-up period of 7.3 ± 2.1 years (mean ± SD). C-reactive protein concentrations were compared between living and deceased subgroups along with other known risk factors for cardiovascular disease, including blood lipids. Logistic regression was performed to determine risk for mortality associated with increasing C-reactive protein concentrations. RESULTS: At follow-up 160 individuals (18.7%) were deceased. No significant differences in baseline serum glucose or lipid measures were observed between living and deceased subgroups. Baseline C-reactive protein concentrations were significantly higher in the deceased subgroup (9.37 ± 15.94) compared with the living subgroup (5.36 ± 7.91 mg/l; P < 0.0001). Participants with C-reactive protein concentrations of 3-10 mg/l were approximately two times more likely to be deceased at follow-up (OR 2.06; 95% CI 1.17-3.62); those with C-reactive protein >10 mg/l were more than five times more likely to be deceased (OR 5.24; CI 2.80-9.38). CONCLUSIONS: This study documents the utility of C-reactive protein in predicting risk for all-cause mortality in European Americans with Type 2 diabetes and supports its use as a screening tool in risk prediction models.


Asunto(s)
Proteína C-Reactiva/metabolismo , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/mortalidad , Angiopatías Diabéticas/sangre , Angiopatías Diabéticas/mortalidad , Población Blanca/estadística & datos numéricos , Anciano , Biomarcadores/metabolismo , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Inflamación/sangre , Inflamación/mortalidad , Modelos Logísticos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Medición de Riesgo , Factores de Riesgo , Análisis de Supervivencia , Estados Unidos/epidemiología
2.
Br J Sports Med ; 44(4): 222-6, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18272539

RESUMEN

OBJECTIVE: To evaluate the ability of a probiotic Lactobacillus fermentum VRI-003 (PCC) to enhance the mucosal immune system of elite athletes. DESIGN AND SETTING: A double-blind, placebo-controlled, crossover trial was conducted over a 4-month period of winter training. PARTICIPANTS; 20 healthy elite male distance runners. INTERVENTIONS: PCC was given at a daily dose of 1.26 x 10(10) as a freeze-dried powder in gelatin capsules. Placebo capsules contained an inert excipient. MAIN OUTCOME MEASURES: Treadmill performance (monthly), mucosal and systemic immunity (monthly), training (daily) and illness (daily) were assessed. Serum cytokine levels, salivary IgA levels and incidence, duration and severity of respiratory tract infections were measured. RESULTS: Subjects reported less than half the number of days of respiratory symptoms during PCC treatment (30 days) compared with placebo (72 days, p<0.001). Illness severity was also lower for episodes occurring during the PCC treatment (p = 0.06). There were no significant differences in the mean change in salivary IgA and IgA1 levels, or in interleukin (IL)4 and IL12 levels, between treatments. However, PCC treatment elicited a twofold (p = 0.07) greater change in whole-blood culture interferon gamma (IFNgamma) compared with placebo. No substantial changes in running performance measures were seen over the study period. CONCLUSIONS: Prophylactic administration of PCC was associated with a substantial reduction in the number of days and severity of respiratory illness in a cohort of highly trained distance runners. Maintenance of IFNgamma levels may be one mechanism underpinning the positive clinical outcomes.


Asunto(s)
Inmunidad Mucosa/fisiología , Limosilactobacillus fermentum , Resistencia Física/inmunología , Probióticos/administración & dosificación , Carrera/fisiología , Administración Oral , Adulto , Atletas , Estudios Cruzados , Citocinas/metabolismo , Método Doble Ciego , Humanos , Masculino , Cumplimiento de la Medicación , Probióticos/farmacología
3.
Br J Sports Med ; 44(2): 127-33, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18523036

RESUMEN

OBJECTIVE: In this study, the effects of Difflam Forte Anti-inflammatory Throat Spray on the incidence of upper respiratory symptoms (URS) and inflammatory responses after a half-marathon race were investigated. DESIGN AND SETTING: Double-blind placebo-controlled randomised trial conducted in association with a half-marathon event. PARTICIPANTS: 45 well-trained half-marathon runners. INTERVENTIONS: Difflam (n = 25) or placebo (n = 20) throat sprays were self-administered three times daily for 1 week before and 2 weeks after the race. MAIN OUTCOME MEASURES: Self-reported respiratory symptoms; plasma prostaglandin E(2), myeloperoxidase, interleukin (IL) 6, IL8, IL10 and IL1 receptor antagonist (IL1ra) concentrations; and salivary myeloperoxidase and IL6 concentrations. RESULTS: All subjects completed the intervention without reporting any adverse events. The proportion of athletes reporting URS was not substantially different between Difflam (52%) and placebo (56%) groups (p = 0.82). However, symptom severity scores were approximately 29% lower during Difflam treatment (4.7 (7.4) vs 6.6 (9.6)) AU). Post-exercise responses in plasma inflammatory markers did not differ substantially between Difflam and placebo groups. Post-race increases in salivary myeloperoxidase ( approximately 63%; trivial to moderate difference; p = 0.13) and salivary IL6 ( approximately 50%; trivial to moderate difference; p = 0.25) were greater in the Difflam group. CONCLUSIONS: Prophylactic use of the Difflam reduced the severity, but not the frequency, of URS among half-marathon runners. Post-race increases in systemic inflammatory markers were not altered by Difflam use, but markers of local inflammation (salivary myeloperoxidase and IL6) were augmented in the Difflam compared with the placebo group.


Asunto(s)
Antiinflamatorios/uso terapéutico , Bencidamina/uso terapéutico , Enfermedades Respiratorias/prevención & control , Carrera/fisiología , Adulto , Dinoprostona/metabolismo , Método Doble Ciego , Femenino , Humanos , Interleucinas/metabolismo , Masculino , Vaporizadores Orales , Peroxidasa/metabolismo , Saliva/química , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
4.
Int J Sports Med ; 31(3): 207-12, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20175040

RESUMEN

This study examined the influence of 28 days of dietary carbohydrate (CHO) supplementation on plasma cytokine responses to cycle ergometry. Sixteen highly trained male cyclists and triathletes (age: 30.6+/-5.6 y; VO2max: 64.8+/-4.7 mL x kg(-1) x min(-1); mean+/-SD) participated in the study. One group (n=8) consumed a higher-CHO (8.5+/-1.7 g x kg(-1) body mass.day (-1)) diet for 28 days; a second group (n=8) consumed a moderate-CHO diet (5.3+/-0.4 g x kg (-1) x day (-1)). Total daily energy intakes were similar between the two groups. Cytokine responses to cycle ergometry were assessed prior to and again following the dietary intervention period. The cycle ergometry protocol involved 100 min steady state cycling at 70% VO2max followed by a time trial of approximately 30 min. Athletes were provided with 15 mL x kg (-1) x h (-1) of water during each trial. Blood samples were collected pre-, immediately post- and 1 h post-exercise for determination of plasma glucose and pro-inflammatory (IL-6, IL-8) and anti-inflammatory (IL-10, IL-1ra) cytokine concentrations. Cytokine responses to cycle ergometry were not substantially altered following the 28-day higher-CHO diet. In contrast, following the 28-day moderate-CHO diet, there were approximately 30-50% reductions (p=0.08-0.11) in anti-inflammatory cytokine responses post-exercise. These findings suggest that increased dietary CHO content alone does not effectively attenuate the pro-inflammatory cytokine response to exercise, however, there may be a small reduction in the anti-inflammatory cytokine response.


Asunto(s)
Citocinas/sangre , Carbohidratos de la Dieta/administración & dosificación , Suplementos Dietéticos , Ejercicio Físico/fisiología , Consumo de Oxígeno , Adaptación Fisiológica , Adulto , Ciclismo/fisiología , Glucemia , Intervalos de Confianza , Citocinas/efectos de los fármacos , Dieta , Ergometría , Tolerancia al Ejercicio , Humanos , Proteína Antagonista del Receptor de Interleucina 1 , Interleucina-10 , Interleucina-6 , Interleucina-8 , Masculino , Carrera/fisiología , Natación/fisiología , Factores de Tiempo
5.
Cardiovasc Res ; 76(2): 280-91, 2007 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-17716638

RESUMEN

OBJECTIVE: Diabetic cardiomyopathy is an increasingly recognized cause of cardiac failure despite preserved left ventricular systolic function. Given the over-expression of angiotensin II in human diabetic cardiomyopathy, we hypothesized that combining hyperglycaemia with an enhanced tissue renin-angiotensin system would lead to the development of diastolic dysfunction with adverse remodeling in a rodent model. METHODS: Homozygous (mRen-2)27 rats and non-transgenic Sprague Dawley (SD) rats were randomized to receive streptozotocin (diabetic) or vehicle (non-diabetic) and followed for 6 weeks. Prior to tissue collection, animals underwent pressure-volume loop acquisition. RESULTS: Diabetic Ren-2 rats developed impairment of both active and passive phases of diastole, accompanied by reductions in SERCA-2a ATPase and phospholamban along with activation of the fetal gene program. Structural features of diabetic cardiomyopathy in the Ren-2 rat included interstitial fibrosis, cardiac myocyte hypertrophy and apoptosis in conjunction with increased activity of transforming growth factor-beta (p<0.01 compared with non-diabetic Ren-2 rats for all parameters). No significant functional or structural derangements were observed in non-transgenic, SD diabetic rats. CONCLUSION: These findings indicate that the combination of enhanced tissue renin-angiotensin system and hyperglycaemia lead to the development of diabetic cardiomyopathy. Fibrosis, and myocyte hypertrophy, a prominent feature of this model, may be a consequence of activation of the pro-sclerotic cytokine, transforming growth factor-beta, by the diabetic state.


Asunto(s)
Diabetes Mellitus Experimental/complicaciones , Diástole , Insuficiencia Cardíaca/fisiopatología , Miocardio/patología , Renina/genética , Animales , Animales Modificados Genéticamente , Apoptosis , Modelos Animales de Enfermedad , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/patología , Masculino , Ratas , Ratas Sprague-Dawley , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/análisis , Estreptozocina , Factor de Crecimiento Transformador beta/análisis
6.
Diabetes Metab ; 43(2): 163-166, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27745826

RESUMEN

AIM: Relationships between the intestinal microbiota, intestinal permeability and inflammation in the context of risk for obesity-associated disease continue to be of interest. The aim of the study was to examine the associations between intestinal permeability and type 2 diabetes (T2D). METHODS: A total of 130 individuals with T2D (age: 57.5±6.2 years (mean±SD); BMI: 30.4±3.2; 45% female) and 161 individuals without T2D (age: 37.4±12.5 years; BMI: 25.1±3.9; 65% female) were included in the study. Assessment of intestinal permeability included measurement of circulating lipopolysaccharide (LPS), LPS-binding protein (LBP) and intestinal fatty acid binding protein (iFABP) concentrations, which were used for calculation of a derived permeability risk score (PRS). Associations between permeability measures and T2D status were assessed using logistic regression models. RESULTS: LBP (∼34%, P<0.001), iFABP (∼46%, P<0.001) and the PRS (∼24% P<0.001) were all significantly higher in the T2D affected individuals. Individuals with a PRS in the upper tertile were 5.07 times more likely (CI: 1.72-14.95; P=0.003) to have T2D when models were adjusted for age, sex and BMI. There was a trend towards improved prediction when including the PRS in models containing age, sex and BMI (AUC: 0.954 versus 0.962; P=0.06). CONCLUSION: These data demonstrate differences in measures of intestinal permeability between individuals with and without T2D. The utility of using intestinal permeability measures as a tool for predicting T2D risk in at risk individuals should be further investigated.


Asunto(s)
Proteínas Portadoras/sangre , Proteínas de Unión a Ácidos Grasos/sangre , Mucosa Intestinal/metabolismo , Lipopolisacáridos/sangre , Glicoproteínas de Membrana/sangre , Proteínas de Fase Aguda , Adolescente , Adulto , Anciano , Presión Sanguínea/fisiología , Diabetes Mellitus Tipo 2 , Femenino , Humanos , Masculino , Persona de Mediana Edad , Permeabilidad , Factores de Riesgo , Adulto Joven
7.
Circ Res ; 86(2): 158-65, 2000 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-10666411

RESUMEN

Vascular hypertrophy, a feature of experimental and human diabetes, has been implicated in the pathogenesis of the microvascular and macrovascular complications of the disease. In the present study, we sought to examine the role of endogenous endothelin and its relation to vascular growth factors in the mediation of vascular hypertrophy in experimental diabetes and to examine the contribution of mast cells to this process. Vessel morphology, endothelin, growth factor gene expression, and matrix deposition were studied in the mesenteric arteries of control and streptozotocin-induced diabetic Sprague-Dawley rats treated with or without the dual endothelin(A/B) receptor antagonist bosentan (100 mg x kg(-1) x d(-1)) during a 3-week period. Compared with control animals, diabetic animals had significant increases in vessel weight, wall-to-lumen ratio, mast cell infiltration, extracellular matrix deposition, and gene expression of epidermal growth factor (EGF) and transforming growth factor-beta(1). In diabetic, but not control, vessels, not only were EGF mRNA and endothelin present in endothelial cells, but also their expression was observed in adventitial mast cells. Immunoreactive endothelin was present in the media of mesenteric vessels of diabetic, but not control, animals. Bosentan treatment significantly reduced mesenteric weight, wall-to-lumen ratio, mast cell infiltration, matrix deposition, and EGF mRNA but did not prevent the overexpression of transforming growth factor-beta(1) mRNA in diabetic rats. These findings suggest that endogenous endothelin and EGF may play a role in diabetes-induced vascular hypertrophy and that mast cells may be pathogenetically involved in this process.


Asunto(s)
Diabetes Mellitus Experimental/patología , Antagonistas de los Receptores de Endotelina , Endotelio Vascular/patología , Factor de Crecimiento Epidérmico/genética , Mastocitos/inmunología , Animales , Antihipertensivos/farmacología , Northern Blotting , Bosentán , Diabetes Mellitus Experimental/tratamiento farmacológico , Angiopatías Diabéticas/tratamiento farmacológico , Angiopatías Diabéticas/patología , Endotelio Vascular/inmunología , Matriz Extracelular/patología , Expresión Génica/fisiología , Hipertrofia , Hibridación in Situ , Masculino , Arterias Mesentéricas/patología , ARN Mensajero/análisis , Ratas , Ratas Sprague-Dawley , Sulfonamidas/farmacología
8.
Chem Commun (Camb) ; 52(99): 14318-14321, 2016 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-27886299

RESUMEN

The Nobel prize in chemistry in 2016 was awarded for 'the design and synthesis of molecular machines'. Here we designed and assembled a molecular machine for the detection of specific RNA molecules. An association of several DNA strands, named multifunctional DNA machine for RNA analysis (MDMR1), was designed to (i) unwind RNA with the help of RNA-binding arms, (ii) selectively recognize a targeted RNA fragment, (iii) attract a signal-producing substrate and (iv) amplify the fluorescent signal by catalysis. MDMR1 enabled detection of 16S rRNA at concentrations ∼24 times lower than that by a traditional deoxyribozyme probe.


Asunto(s)
ADN/química , Nanotecnología , ARN/análisis
9.
Diabetes ; 41(4): 499-507, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1376703

RESUMEN

Diabetes-associated kidney enlargement is associated with increased kidney insulinlike growth factor I (IGF-I) binding. IGF-I binds to the type I IGF receptor, which mediates most of its actions, and to specific binding proteins (IGFBPs), which modulate its actions. To explore the nature and extent of IGF-I binding in the kidney, in vitro autoradiography was used to map the distribution of IGF binding in control and diabetic rat kidney. Specificity studies were performed with increasing concentrations of unlabeled IGF-I, IGF-II, des(1-3)IGF-I (an IGF-I derivative that binds to receptors normally but with decreased affinity to binding proteins), and insulin. In control rats, diffuse binding was found throughout the kidney with increased density in the papilla. Binding specificity in the cortex and outer medulla was typical of the type I IGF receptor (IGF-I = des[1-3]IGF-I greater than IGF-II much greater than insulin). Binding in the outer medulla of diabetic kidney was typical of the type I IGF receptor. A marked focal increase in proximal tubular binding occurred in 13 of 22 postpubertal diabetic rats. Binding specificity of the proximal tubular binding was consistent with the predominance of an IGF binding protein (IGF-I = IGF-II greater than des[1-3]IGF-I with minimal displacement by insulin). Northern-blot analysis revealed increased IGFBP-1 and IGFBP-3 mRNA in cortical tissue from diabetic rats displaying increased proximal tubular binding but not from diabetic rats not displaying this phenomenon. As cell surface association of IGFBPs is linked to potentiation of IGF activity, a possible mechanism for potentiation of local IGF-I action may be provided.


Asunto(s)
Proteínas Portadoras/metabolismo , Diabetes Mellitus Experimental/metabolismo , Túbulos Renales Proximales/metabolismo , Animales , Autorradiografía , Northern Blotting , Proteínas Portadoras/análisis , Proteínas Portadoras/genética , Membrana Celular/química , Membrana Celular/ultraestructura , Diabetes Mellitus Experimental/genética , Insulina/metabolismo , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina , Factor I del Crecimiento Similar a la Insulina/análisis , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor II del Crecimiento Similar a la Insulina/análisis , Factor II del Crecimiento Similar a la Insulina/metabolismo , Radioisótopos de Yodo , Túbulos Renales Proximales/química , Túbulos Renales Proximales/ultraestructura , Masculino , Unión Proteica , Ratas , Ratas Endogámicas , Receptores de Superficie Celular/análisis , Receptores de Superficie Celular/metabolismo , Receptores de Somatomedina
10.
Diabetes ; 48(11): 2229-39, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10535459

RESUMEN

It has been suggested that the cytokine vascular endothelial growth factor (VEGF) has an important role in the pathogenesis of diabetic retinopathy, but its role in nephropathy has not been clearly demonstrated. Assessment of VEGF, 125I-VEGF binding, and vascular endothelial growth factor receptor-2 (VEGFR-2) in the kidney was performed after 3 and 32 weeks of streptozotocin-induced diabetes. Gene expression of both VEGF and VEGFR-2 was assessed by Northern blot analysis and the localization of the ligand and receptor was examined by in situ hybridization. VEGF and VEGFR-2 protein were also evaluated by immunohistochemistry. Binding of the radioligand 125I-VEGF was evaluated by in vitro and in vivo autoradiography. Diabetes was associated with increased renal VEGF gene expression. VEGF mRNA and protein were localized to the visceral epithelial cells of the glomerulus and to distal tubules and collecting ducts in both diabetic and nondiabetic rats. Renal VEGFR-2 mRNA was increased after 3 weeks of diabetes but not in long-term diabetes. In situ hybridization and immunohistochemical studies revealed that glomerular endothelial cells were the major site of VEGFR-2 expression. In addition, VEGFR-2 gene expression was detected in cortical and renomedullary interstitial cells and on endothelial cells of peritubular capillaries. There was an increase in 125I-VEGF binding sites after 3 but not 32 weeks of diabetes. The major VEGF binding sites were in the glomeruli. 125I-VEGF binding was also observed in medullary rays and in the renal papillae. These studies indicate an early and persistent increase in renal VEGF gene expression in association with experimental diabetes. In addition, an early and transient increase in renal VEGF receptors was also observed in diabetic rats. These findings are consistent with a role for VEGF in mediating some of the changes observed in the diabetic kidney.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Factores de Crecimiento Endotelial/genética , Regulación de la Expresión Génica , Riñón/metabolismo , Linfocinas/genética , Proteínas Tirosina Quinasas Receptoras/genética , Receptores de Factores de Crecimiento/genética , Animales , Glucemia/metabolismo , Presión Sanguínea , Northern Blotting , Peso Corporal , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/fisiopatología , Factores de Crecimiento Endotelial/metabolismo , Inmunohistoquímica , Hibridación in Situ , Linfocinas/metabolismo , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptores de Factores de Crecimiento/metabolismo , Receptores de Factores de Crecimiento Endotelial Vascular , Transcripción Genética , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
11.
J Invest Dermatol ; 69(2): 205-10, 1977 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-881567

RESUMEN

Quantitative and qualitative differences of the nuclear and nucleolar structures in normal and psoriatic (involved and uninvolved) epidermis were revealed with the electron microscope. The size of nuclei and nucleoli was increased, the frequency of nuclear bodies was increased, and the relative amount of heterochromatin was decreased in involved skin compared to normal or uninvolved skin. There was no significant difference between normal skin and uninvolved skin of psoriasis. In addition to these changes, multiple fibrillar centers within nucleoli and small masses of chromatin in the epidermal nucleoplasm were observed very frequently in involved skin, while rarely or not at all in normal and uninvolved skin. These results suggest that involved psoriatic keratinocytes have increased metabolic activity and abnormal protein synthesis, having undergone gene derepression.


Asunto(s)
Nucléolo Celular/ultraestructura , Núcleo Celular/ultraestructura , Psoriasis/patología , Piel/ultraestructura , Adolescente , Adulto , Biopsia , Gránulos Citoplasmáticos/ultraestructura , Femenino , Heterocromatina/ultraestructura , Humanos , Masculino , Persona de Mediana Edad , Membrana Nuclear/ultraestructura
12.
J Invest Dermatol ; 78(4): 319-22, 1982 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7069211

RESUMEN

The epidermis consists of a heterogeneous population of cells including Langerhans cells, Merkel cells, melanocytes, and keratinocytes in various stages of differentiation. The current study was undertaken to determine if skin cell suspensions can be separated into morphologically and/or functionally distinct fractions. Skin cells were suspended by trypsinization and separated into multiple fractions by velocity sedimentation. Certain fractions reproducibly stimulated proliferation of allogeneic lymphocytes in the skin cell lymphocyte reaction, whereas other fractions, containing larger cells, supported growth of keratinocyte colonies in cell cultures. These results indicate that stimulation in the skin cell lymphocyte reaction and growth of keratinocyte colonies are mediated by distinct cells, separable by velocity sedimentation.


Asunto(s)
Separación Celular/métodos , Piel/citología , División Celular , Células Cultivadas , Humanos , Activación de Linfocitos , Piel/inmunología , Piel/ultraestructura
13.
J Invest Dermatol ; 78(1): 32-7, 1982 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7033395

RESUMEN

All nucleated cells express HLA-A, B, and C antigens. However, only a few cells, including epidermal cells, demonstrate HLA-DR antigens which are potent transplantation immunogens in man. The current study was undertaken to determine if epidermal cell continue to synthesize and/or express HLA-DR antigens after prolonged in vitro culture. Epidermal cells cultured for 7 days or more no longer stimulated allogeneic lymphocytes in the epidermal cell-lymphocyte reaction. Indirect immunofluorescence light microscopy of cultured cells using mouse monoclonal antibody to HLA-DR antigen confirmed that these cells do not express HLA-DR antigens whereas they retain beta 2-microglobulin. Detergent extracts of 12-day cultured epidermal cells biosynthetically labeled with 35 S-methionine were immunoprecipitated with monoclonal anti-DR antibody and analyzed by the method of two-dimensional polyacrylamide gel electrophoresis. No radiolabeled proteins were found on these gels in the regions where HLA-DR molecules are known to migrate. These data indicate that HLA-DR antigen is absent from cultured epidermal cells. Finally, we describe a technique for growing epidermal cells on a gelatin membrane which allows subsequent removal of intact cell monolayers from the culture dish. Such monolayers may be useful for purposes of transplantation.


Asunto(s)
Antígenos de Histocompatibilidad Clase II/análisis , Piel/inmunología , Células Cultivadas , Electroforesis en Gel de Poliacrilamida , Técnica del Anticuerpo Fluorescente , Antígenos HLA-DR , Humanos , Células de Langerhans/inmunología , Linfocitos/inmunología , Membranas Artificiales , Receptores Fc/análisis , Piel/ultraestructura
14.
Endocrinology ; 126(6): 3033-42, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1693565

RESUMEN

We have shown that a pleomorphic cell line of abnormal human karyotype derived from a stomach carcinoma (LIM-1839) proliferates in serum-free medium, expresses insulin-like growth factor II (IGF-II) mRNA, and secretes IGF-II (up to 56 ng/ml in serum-free conditioned medium, as measured in a rat liver RRA. No detectable levels of IGF-I can be measured in serum-free conditioned medium by RIA. These cells also secrete IGF-binding proteins, detected by a charcoal adsorption assay. The release of IGF-II and IGF binding proteins into serum-free conditioned medium (1.7 pmol/10(6) cells.24 h and 0.8 pmol binding sites/10(6) cells.24 h for 3 days, respectively) is inhibited 80% by cycloheximide (10 micrograms/ml). The LIM-1839 cells have type I and type II IGF receptors, determined by affinity cross-linking and competition binding studies. These cells proliferated 1.6-fold over 4 days in serum-free medium, with fresh medium changes on days 0 and 2: their growth was inhibited 56% by 40 micrograms/ml Sm 1.2, a monoclonal antibody which recognizes IGF-I and IGF-II. The addition of 20 and 50 ng/ml multiplication stimulating activity (rat IGF-II) caused 1.8- and 1.7-fold increases in cell growth between days 0 and 4 compared to controls, while [Thr59]IGF-I, at 20 and 50 ng/ml, caused 1.6- and 2.0-fold increases. Insulin, at 2 and 10 micrograms/ml, had no significant effect. The stimulatory effects of endogenous and exogenous IGFs on LIM-1839 cell proliferation were inhibited by a monoclonal antibody to the type I IGF receptor, alpha IR-3. These results suggest that the LIM-1839 cells are biologically responsive to endogenously produced IGF-II, and may thereby provide an in vitro model for autocrine regulation of human tumor growth by IGF-II.


Asunto(s)
Factor II del Crecimiento Similar a la Insulina/fisiología , Somatomedinas/fisiología , Neoplasias Gástricas/patología , Anticuerpos Monoclonales/farmacología , Unión Competitiva , Sangre , Proteínas Portadoras/metabolismo , División Celular , Cicloheximida/farmacología , Expresión Génica , Homeostasis , Humanos , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina , Factor I del Crecimiento Similar a la Insulina/inmunología , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor II del Crecimiento Similar a la Insulina/genética , Factor II del Crecimiento Similar a la Insulina/inmunología , Hibridación de Ácido Nucleico , ARN Mensajero/genética , Receptores de Superficie Celular/metabolismo , Receptores de Somatomedina , Neoplasias Gástricas/metabolismo , Células Tumorales Cultivadas
15.
Eur J Hum Genet ; 5(1): 15-21, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9156316

RESUMEN

Homocystinuria, due to a deficiency of the enzyme cystathionine beta-synthase (CBS), is an inborn error of sulphur-amino acid metabolism. This is an autosomal recessive disease which results in hyperhomocysteinaemia and a wide range of clinical features, including optic lens dislocation, mental retardation, skeletal abnormalities and premature thrombotic events. We report the identification of 5 missense mutations in the protein-coding region of the CBS gene from 3 patients with pyridoxine-nonresponsive homocystinuria. Reverse-transcription PCR was used to amplify CBS cDNA from each patient and the coding region was analysed by direct sequencing. The mutations detected included 3 novel (1058C-->T, 992C-->A and 1316G-->A) and 2 previously identified (430G-->A and 833C-->T) base alterations in the CBS cDNA. Each of these mutations predicts a single amino acid substitution in the CBS polypeptide. Appropriate cassettes of patient CBS cDNA, containing each of the above defined mutations, were used to replace the corresponding cassettes of normal CBS cDNA sequence within the bacterial expression vector pT7-7. These recombinant mutant and normal CBS constructs were expressed in Escherichia coli cells and the catalytic activities of the mutant proteins were compared with normal. All of the mutant proteins exhibited decreased catalytic activity in vitro, which confirmed the association between the individual mutation and CBS dysfunction in each patient.


Asunto(s)
Cistationina betasintasa/genética , Homocistinuria/genética , Mutación , Adolescente , Western Blotting , Niño , Cistationina betasintasa/deficiencia , Análisis Mutacional de ADN , Femenino , Homocisteína/análisis , Homocistinuria/fisiopatología , Homocistinuria/terapia , Humanos , Masculino , Persona de Mediana Edad , Linaje , Reacción en Cadena de la Polimerasa , Piridoxina/uso terapéutico , Mapeo Restrictivo
16.
Biomaterials ; 8(6): 500-2, 1987 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3427151

RESUMEN

The hydrated surface of a hydrogel-coated latex urinary catheter has been examined using low temperature SEM, and its appearance compared with those of some other catheter surfaces. The effect of the coating is to smooth over most of the ripples and fissures of the underlying latex. On hydration the hydrogel surface becomes even smoother, with shallower furrows. The surface topography compares favourably with that of 100% silicone, which has a uniformly rippled yet smooth appearance.


Asunto(s)
Catéteres de Permanencia , Polietilenglicoles , Cateterismo Urinario , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato , Látex , Microscopía Electrónica de Rastreo , Diseño de Prótesis
17.
Ann N Y Acad Sci ; 777: 338-43, 1996 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-8624110

RESUMEN

It has previously been shown that stimulation of muscarinic m1 or m3 receptors can, by generating diacylglycerol (DAG) and activating protein kinase C (PKC), accelerate the breakdown of the amyloid precursor protein (APP) to form soluble, non-amyloidogenic peptides (APPs). This relationship has been demonstrated in human glioma and neuroblastoma cells as well as in transfected human embryonic kidney (HEK) cells and PC12 cells. We now provide evidence that stimulation of metabotropic glutamate receptors (mGluRs), which also are coupled to DAG and PKC, similarly accelerates processing of APP into non-amyloidogenic APPs in hippocampal neurons and cortical astrocytes derived from normal fetal rats. The mGluR antagonist, L(+)-2-amino-3-phosphonopropionic acid (L-AP3), and GF 109203X, an inhibitor of PKC, both blocked the release of APPs from hippocampal neurons and astrocytes evoked by glutamate receptor stimulation. Inasmuch as glutamatergic neurons in cortex and hippocampus are known to be damaged in Alzheimer's disease, our findings suggest that amyloid formation may be enhanced by the resulting glutamate deficiency and that selective mGluR agonists may be useful in facilitating synaptic efficacy and treating the disease.


Asunto(s)
Precursor de Proteína beta-Amiloide/metabolismo , Corteza Cerebral/metabolismo , Hipocampo/metabolismo , Procesamiento Proteico-Postraduccional , Receptores de Glutamato Metabotrópico/fisiología , Animales , Astrocitos/metabolismo , Corteza Cerebral/citología , Hipocampo/citología , Neuronas/metabolismo , Ratas/embriología
18.
Kidney Int Suppl ; 71: S31-6, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10412733

RESUMEN

BACKGROUND: It has been suggested that lipids promote renal injury and that 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase inhibitors confer renoprotection in certain renal diseases, including diabetic nephropathy. METHODS: Sprague-Dawley rats were randomized to sham, subtotal nephrectomy (STNx) or STNx + atorvastatin groups. After 12 weeks, proteinuria, renal function, glomerular injury, renal transforming growth factor-beta (TGF-beta) gene expression and macrophage (ED1-positive cells) accumulation were assessed. In addition, the effects of HMG CoA reductase in human diabetic nephropathy were reviewed. RESULTS: Atorvastatin therapy was associated with a modest reduction in proteinuria and glomerulosclerosis without influencing lipid levels or renal function in STNx rats. These effects were associated with decreased renal TGF-beta 1 gene expression and less glomerular and tubulointerstitial macrophage accumulation. The renoprotective effects of HMG CoA reductase inhibitors in both insulin- and non-insulin-dependent diabetic subjects with either incipient or overt nephropathy appear to be highly variable. CONCLUSIONS: HMG CoA reductase inhibition appears to confer renoprotection via effects on prosclerotic cytokines such as TGF-beta and macrophage accumulation, independent of their lipid-lowering properties. The role of lipid-lowering agents in early or overt diabetic nephropathy remains to be fully ascertained.


Asunto(s)
Hiperlipidemias/fisiopatología , Enfermedades Renales/fisiopatología , Animales , Anticolesterolemiantes/uso terapéutico , Atorvastatina , Ensayos Clínicos como Asunto , Nefropatías Diabéticas/tratamiento farmacológico , Progresión de la Enfermedad , Expresión Génica/efectos de los fármacos , Ácidos Heptanoicos/uso terapéutico , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hibridación in Situ , Enfermedades Renales/tratamiento farmacológico , Enfermedades Renales/patología , Glomérulos Renales/efectos de los fármacos , Glomérulos Renales/metabolismo , Glomérulos Renales/patología , Lovastatina/uso terapéutico , Masculino , Nefrectomía , Pravastatina/uso terapéutico , Pirroles/uso terapéutico , Ratas , Ratas Sprague-Dawley , Simvastatina/uso terapéutico , Factor de Crecimiento Transformador beta/genética
19.
FEMS Microbiol Lett ; 192(2): 249-56, 2000 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11064203

RESUMEN

Investigation of the hemolytic phenotype under anaerobic growth conditions of an avian Pasteurella multocida strain, PBA100, resulted in the identification and characterisation of a gene encoding an esterase enzyme, mesA, that conferred a hemolytic phenotype in Escherichia coli under anaerobic conditions. MesA appeared to be expressed and functional under anaerobic and aerobic conditions in both E. coli and P. multocida. A P. multocida mesA mutant was generated which resulted in the loss of acetyl esterase activity under anaerobic conditions. However, this mutation did not cause any attenuation of virulence for mice nor a detectable change to the anaerobic hemolytic phenotype of P. multocida. In E. coli MesA appeared to cause hemolysis indirectly by the induction of the latent E. coli K-12 cytolysin, sheA.


Asunto(s)
Proteínas Bacterianas/genética , Esterasas , Genes Bacterianos , Pasteurella multocida/genética , Secuencia de Aminoácidos , Animales , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Bovinos , Clonación Molecular , Escherichia coli/genética , Hemólisis/genética , Caballos , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Mutación , Pasteurella multocida/enzimología , Pasteurella multocida/patogenicidad , Fenotipo , Alineación de Secuencia , Ovinos , Porcinos , Virulencia
20.
Clin Ther ; 15(2): 407-22, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8390918

RESUMEN

A postmarketing surveillance study in 2273 Canadian office practices provided the largest body of clinical experience to date with the angiotensin-converting enzyme (ACE) inhibitor lisinopril in the treatment of mild to moderate essential hypertension. The principal emphasis in this uncontrolled study was safety, assessed in 10,289 patients. Patients with a diastolic blood pressure > 90 mmHg were considered for the study. Both previously untreated patients and those who were experiencing adverse effects from their current antihypertensive regimen were included. Lisinopril was begun at a dose of 10 mg/day. Subsequent dose adjustments, to a maximum of 40 mg/day, were made to achieve optimal blood pressure control (diastolic blood pressure < or = 90 mmHg or > or = 10 mmHg below baseline for > or = 4 weeks at the same dose). Therapy was continued for a minimum of 4 weeks to a maximum of 12 weeks, with patients examined every 2 weeks. The frequencies of adverse effects and laboratory abnormalities were analyzed in all treated patients. All 10,289 patients enrolled were considered in the analysis of safety. One or more adverse effects were reported for 1593 (15.5%) patients, and 802 (7.8%) withdrew from the study because of adverse effects. The most frequent adverse effects were cough (4.0%), dizziness (2.3%), headache (2.1%), asthenia (1.7%), and nausea (1.0%). The physicians' global assessment rated overall tolerability as very good or good for 77.1% of the patients. Antihypertensive effect was evaluated in 5886 patients who met the criteria for efficacy analysis. The criterion response was attained in 5141 (87.3%) patients, with 68.6% responding to 10 mg/day of lisinopril, 26.3% to 20 mg/day, and 3.2% to 40 mg/day (the other 1.9% responded at nonstandard doses). Lisinopril was safe and well-tolerated. Except for cough, class effects of ACE inhibitors were rarely encountered. The results of the efficacy analysis confirm the established efficacy of lisinopril in patients with mild to moderate essential hypertension.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/efectos adversos , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Dipéptidos/efectos adversos , Dipéptidos/uso terapéutico , Hipertensión/tratamiento farmacológico , Adulto , Anciano , Presión Sanguínea/efectos de los fármacos , Canadá , Femenino , Humanos , Lisinopril , Masculino , Persona de Mediana Edad , Vigilancia de Productos Comercializados
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA