Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 43
Filtrar
1.
Occup Med (Lond) ; 71(4-5): 215-218, 2021 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-34008016

RESUMEN

BACKGROUND: Healthcare workers (HCWs) accounted for a significant proportion of COVID-19 infections worldwide. Retrospective seroprevalence surveys are often used to screen for unidentified previous infection with SARS-CoV-2. However, the rate of humoral response in HCWs affected by COVID-19 is not well-defined. AIMS: To assess the specific IgG humoral response in symptomatic and asymptomatic SARS-CoV-2-infected HCWs and identify potential factors associated with humoral response. METHODS: We prospectively recruited 204 HCWs with RT-PCR-confirmed COVID-19 infection to evaluate SARS-CoV-2 humoral response. Serum-IgG antibodies against SARS-CoV-2 were analysed using two commercially available serological assays. A logistic regression was performed to identify independent factors associated with positive IgG serology test. RESULTS: Overall, the SARS-CoV-2 IgG seropositivity rate was 77%. This seropositivity rate was higher in symptomatic than in asymptomatic COVID-19 infection (83% versus 57%; P < 0.001) and in older HCWs.. The seropositivity rate did not diminish with time. In logistic regression, only a history of COVID-19 symptoms and age were identified as independent factors associated with the detection of anti-SARS-CoV-2 IgG antibodies. CONCLUSIONS: SARS-CoV-2 IgG antibodies are found significantly more frequently in symptomatic and in older HCWs. The fact that not all COVID-19 HCWs develop detectable IgG is vital for the interpretation of COVID-19 seroprevalence surveys.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anciano , Personal de Salud , Humanos , Inmunoglobulina G , Estudios Retrospectivos , Estudios Seroepidemiológicos
2.
Diabet Med ; 36(4): 465-472, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30343524

RESUMEN

AIM: To test the measurement properties of the revised and updated Pediatric Quality of Life Inventory (PedsQL) 3.2 Diabetes Module originally developed in Type 1 diabetes in youth with Type 2 diabetes. METHODS: The PedsQL 3.2 Diabetes Module and PedsQL Generic Core Scales were administered in a field test study to 100 young people aged 9-25 years with Type 2 diabetes. Factor analysis was conducted to determine the factor structure of the items. RESULTS: The 15-item Diabetes Symptoms Summary Score and 12-item Type 2-specific Diabetes Management Summary Score were empirically derived through factor analysis. The Diabetes Symptoms and Type 2-specific Diabetes Management Summary Scores showed acceptable to excellent reliability across the age groups tested (α = 0.85-0.94). The Diabetes Symptoms and Type 2-specific Diabetes Management Summary Scores evidenced construct validity through large effect size correlations with the Generic Core Scales Total Scale Score (r = 0.67 and 0.57, respectively). HbA1c was correlated with the Diabetes Symptoms and Type 2-specific Diabetes Management Summary Scores (r = -0.13 and -0.22). Minimal clinically important difference (MCID) scores were 5.91 and 7.39 for the Diabetes Symptoms and Type 2-specific Diabetes Management Summary Scores. CONCLUSIONS: The PedsQL 3.2 Diabetes Module Diabetes Symptoms Summary Score and Type 2-specific Diabetes Management Summary Score exhibited satisfactory measurement properties for use as youth self-reported diabetes symptoms and diabetes management outcomes for clinical research and clinical practice for young people with Type 2 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2/epidemiología , Estado de Salud , Psicometría/métodos , Calidad de Vida , Encuestas y Cuestionarios , Adolescente , Adulto , Factores de Edad , Edad de Inicio , Niño , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/psicología , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/psicología , Estudios de Factibilidad , Femenino , Humanos , Masculino , Medición de Resultados Informados por el Paciente , Reproducibilidad de los Resultados , Encuestas y Cuestionarios/normas , Adulto Joven
3.
Allergol Immunopathol (Madr) ; 47(4): 313-321, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30503672

RESUMEN

METHODS: This study assesses the temporal trend of current asthma symptoms prevalence and associated factors in Chilean adolescents from South-Santiago, considering surveys performed in 1994, 2002 and 2015. RESULTS: The prevalence of current asthma symptoms showed a trend to increase from 11.1% in 1994 to 13.4% in 2015 (p<0.001); physician-diagnosed asthma increased from 11.5% to 13.8%, (p<0.001) whereas severe asthma and asthma with exercise decreased (p<0.001). Female adolescents had a higher prevalence of current asthma in the three surveys (p<0.001), and was a risk factor for asthma in the three surveys. In 2002, frequent consumption of meat and potatoes were associated with current asthma while frequent vigorous exercise was protective. Frequent exercise and parental tobacco smoking were risk for asthma in 2015 (p<0.001). Current active tobacco smoking showed a trend to increase reaching a prevalence of 28.9% in 2015 (p<0.001). There was a consistently low proportion of adolescents with current wheezing and asthma diagnosis (32.1% in 2015) and 37.6% of them had no asthma treatment. CONCLUSION: The prevalence of current asthma in adolescents from the studied area would be still increasing. As in other studies, female adolescents had a higher prevalence of current asthma. Current active tobacco smoking has strikingly increased in the studied children while indoor passive tobacco exposure remains inadmissibly high. Our findings suggest that asthma in children is underdiagnosed and undertreated. More attention should be given to female gender, tobacco exposure, air pollution and local diagnostic preferences when studying and interpreting trends of asthma prevalence in adolescents from developing localities.


Asunto(s)
Asma/epidemiología , Factores Sexuales , Adolescente , Chile/epidemiología , Fumar Cigarrillos/efectos adversos , Femenino , Humanos , Masculino , Padres , Prevalencia , Ruidos Respiratorios , Factores de Riesgo , Encuestas y Cuestionarios
4.
Allergol Immunopathol (Madr) ; 44(2): 106-12, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26001339

RESUMEN

BACKGROUND: Ciclesonide (CIC) is an effective inhaled corticosteroid for treating asthmatic children. However, its effect on airway inflammation assessed by the fraction of exhaled nitric oxide (FENO) in children with persistent asthma is virtually unknown. We aimed to assess the effect of once-daily generic CIC, 80 or 160 µg, on FENO, lung function, asthma control and bronchial hyperresponsiveness, in atopic children with persistent asthma. METHODS: This was a 12-week, randomised, double-blind, parallel-group study. Sixty children with mild-to-moderate persistent asthma were recruited. Changes in FENO, asthma control score, lung function (FEV1) and bronchial hyperresponsiveness to methacholine (BHR) were used to assess the effects of both CIC doses. Non-normally distributed variables were log-transformed to approximate normality, and parametric tests were used for comparisons within and between groups at baseline and after 12 weeks of treatment. RESULTS: In the CIC 80 µg group, FENO decreased from 45.0 ppb (95% CI 37.8-53.7) to 32.7 ppb (95% CI 21.0-47.3) at the end of study (P=0.021), whereas in the CIC 160 µg group, FENO decreased from 47.3 ppb (95% CI 40.4-55.3) to 30.5 ppb (95% CI 24.1-38.7) (P<0.001). The difference between groups in FENO at the end of study was not significant (P=0.693). There was a significant improvement of asthma control with both CIC doses but there was no significant change in BHR or FEV1 in either group. CONCLUSION: Once-daily generic ciclesonide (80 µg or 160 µg), for 12 weeks, is effective to improve airway inflammation and asthma control in atopic children with persistent asthma.


Asunto(s)
Antialérgicos/uso terapéutico , Asma/tratamiento farmacológico , Medicamentos Genéricos/uso terapéutico , Espiración/efectos de los fármacos , Hipersensibilidad Inmediata/tratamiento farmacológico , Pregnenodionas/uso terapéutico , Adolescente , Pruebas Respiratorias , Pruebas de Provocación Bronquial , Niño , Chile , Protocolos Clínicos , Estudios de Seguimiento , Humanos , Óxido Nítrico/análisis
5.
Allergol Immunopathol (Madr) ; 43(6): 528-32, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25456527

RESUMEN

BACKGROUND: The fraction of exhaled nitric oxide (FENO) measured using portable devices is increasingly used in the clinical setting to assess asthmatic children. However, there is little and variable information on the reference values obtained using these devices in healthy children from different populations. METHODS: 190 healthy non-smoker children (8-15 years old) were randomly selected from public schools participating in this study. The objective was to determine FENO reference values for healthy Chilean schoolchildren. Healthy individuals were identified by medical interview and parent questionnaire on the use of asthma medications, and current and past symptoms of asthma, rhinoconjunctivitis and eczema. FENO was measured at schools using a portable device with electrochemical sensor (NIO MINOX). Reference values of FENO were expressed as geometric mean and upper limit of the 95% reference interval (right-sided). The relationship of FENO with gender, age, height, body mass, and other factors was assessed by multiple regression, and the difference between groups was contrasted by ANOVA. RESULTS: The FENO geometric mean was 15.4ppb with a 95% reference interval upper limit (right-sided), of 27.4ppb (90%CI 25.6-29.2). The 5th and 95th percentiles were 9.0ppb and 28.0ppb, respectively. Height was the only factor significantly associated to FENO (p=0.022). There was no significant difference in mean FENO regarding age, gender, weight, parent reported rhinoconjunctivitis and eczema. CONCLUSION: This study suggests that FENO values higher than 27ppb are likely to be abnormal and would reflect airway inflammation in children as those in the present study.


Asunto(s)
Asma/diagnóstico , Pruebas Respiratorias/métodos , Óxido Nítrico/metabolismo , Adolescente , Estatura , Niño , Chile , Equipos y Suministros , Espiración , Femenino , Humanos , Masculino , Población , Valores de Referencia
6.
Int J Obes (Lond) ; 37(12): 1603-7, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23609934

RESUMEN

This study investigated the anatomical integrity of the vagal innervation to the gastrointestinal tract following Roux-en-Y gastric bypass (RYGB) in the mouse. Specifically, the surgical procedure was performed in high-fat-fed reporter mice (Phox2b-Cre-tdTomato), in which the entire vagal innervation of the gastrointestinal tract was fluorescently labeled. As a result, our anatomical observations revealed both qualitative and quantitative changes of the vagal supply to the gut after RYGB. This included the extensive denervation of the glandular and distal stomach, and sites of surgical interventions (clipping and anastomosis). Furthermore, the stomach wall after RYGB frequently contained dystrophic axons and endings, suggestive of vagal neurodegeneration. In contrast, RYGB did not significantly modify the innervation to the rest of the intestines and glucostatic organs. In summary, the present study describes a previously unrecognized pattern of vagal remodeling and denervation following RYGB. Our findings may serve as a guideline for future investigations on the role of gut-brain communication in bariatric surgery.


Asunto(s)
Encéfalo/fisiopatología , Sistema Nervioso Entérico/fisiopatología , Derivación Gástrica , Tracto Gastrointestinal/inervación , Obesidad Mórbida/cirugía , Nervio Vago/fisiopatología , Animales , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Sistema Nervioso Entérico/cirugía , Motilidad Gastrointestinal , Ratones , Ratones Endogámicos C57BL , Nervio Vago/cirugía
7.
Allergol Immunopathol (Madr) ; 39(5): 253-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21208718

RESUMEN

BACKGROUND: There is increasing evidence that oxidative stress is involved in the development and severity of bronchiolitis obliterans occurring in post-transplant patients. In developing countries, the most common form of bronchiolitis obliterans occurs after severe lung infection, mainly caused by adenovirus. However, the oxidative status in the lungs of children with post infectious bronchiolitis obliterans is unknown. METHODS: The aim of this study was to measure the oxidant (8-isoprostane and protein carbonyls) and antioxidant (catalase and glutathione peroxidase) activity in the bronchoalveolar lavage fluid of 21 children with post-infectious bronchiolitis obliterans, and to correlate oxidant/antioxidant level with lung function. Lung function was assessed by spirometry and plethysmography, one week prior to fiberbronchoscopy. RESULTS: There was a markedly increased oxidative stress (lipid and protein oxidation) in the bronchoalveolar lavage fluid, and a notorious impairment of lung function demonstrating moderate-severe distal airway narrowing. There was not a significant correlation between the level of oxidants or antioxidants and lung function. There was a consistent antioxidants/oxidants pattern characterised by markedly increased 8-isoprostane and carbonyls, increased GPx and normal catalase activity. CONCLUSION: The present study shows for the first time that children with post-infectious bronchiolitis obliterans have a markedly increased oxidative stress in their lungs.


Asunto(s)
Infecciones por Adenoviridae/fisiopatología , Adenoviridae/inmunología , Bronquiolitis Obliterante/fisiopatología , Pulmón/metabolismo , Estrés Oxidativo , Adenoviridae/patogenicidad , Infecciones por Adenoviridae/complicaciones , Infecciones por Adenoviridae/inmunología , Adolescente , Biomarcadores/metabolismo , Bronquiolitis Obliterante/etiología , Bronquiolitis Obliterante/inmunología , Líquido del Lavado Bronquioalveolar/química , Catalasa/metabolismo , Niño , Dinoprost/análogos & derivados , Dinoprost/análisis , Femenino , Glutatión Peroxidasa/metabolismo , Humanos , Pulmón/inmunología , Pulmón/virología , Masculino , Oxidación-Reducción , Carbonilación Proteica , Pruebas de Función Respiratoria
8.
J Investig Allergol Clin Immunol ; 20(4): 311-23, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20815309

RESUMEN

BACKGROUND: The aim of the International Study of Asthma and Allergies in Childhood (ISAAC) was to evaluate the prevalence of symptoms of eczema among children living in different parts of Latin America. Data were from centers that participated in ISAAC Phase 3. METHODS: This was a cross-sectional questionnaire survey of 93,851 schoolchildren (6 to 7 years old) from 35 centers in 14 Latin American countries and 165,917 adolescents (13 to 14 years old) from 56 centers in 17 Latin American countries. RESULTS: The mean prevalence of current flexural eczema in schoolchildren was 11.3%, ranging from 3.2% in Ciudad Victoria (Mexico) to 25.0% in Barranquilla (Colombia). For adolescents, the prevalence varied from 3.4% in Santo André (Brazil) to 30.2% in Barranquilla (mean prevalence, 10.6%). The mean prevalence of current symptoms of severe eczema among schoolchildren was 1.5%, ranging from 0.3% in Ciudad Victoria, Toluca, and Cuernavaca (Mexico) to 4.9% in La Habana (Cuba). For adolescents, the mean prevalence was 1.4%, ranging from 0.1% in Mexicali Valley (Mexico) to 4.2% in Santa Cruz (Bolivia). These prevalence values are among the highest observed during ISAAC Phase 3. In general, the prevalence of current symptoms of eczema was higher among the Spanish-speaking centers for both schoolchildren and adolescents. CONCLUSION: Environmental risk factors must be evaluated in order to identify potential causes for the differences observed, even in centers from the same country.


Asunto(s)
Dermatitis Atópica/epidemiología , Dermatitis Atópica/fisiopatología , Hispánicos o Latinos , Adolescente , Brasil/etnología , Niño , Estudios Transversales , Exantema , Femenino , Humanos , Cooperación Internacional , América Latina , Portugal/etnología , Prevalencia , Factores de Riesgo , Trastornos del Sueño-Vigilia
9.
Allergol Immunopathol (Madr) ; 38(3): 110-4, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19945208

RESUMEN

BACKGROUND: Common acute viral respiratory infections (colds) are the most frequent cause of exacerbations in infants with recurrent wheezing (RW). However, there is no quantitative information about the effect of colds on the lung function of infants with RW. This study was undertaken to determine the effect of common cold on forced expiratory parameters measured from raised lung volume in infants with RW. METHODS: Spirometric lung function (expiratory flows from raised lung volume) was randomly assessed in 28 infants with RW while they had a common cold and when asymptomatic. RESULTS: It was found that during colds there was a significant decrease in all forced expiratory parameters and this was much more evident for flows (FEF(50%), FEF(75%) and FEF(25-75%)) which were definitively abnormal (less than -1.65 z-score) in the majority of infants. There was not association between family asthma, tobacco exposure, and other factors, with the extent of lung function decrease during colds. Tobacco during pregnancy but not a history of family asthma was significantly associated to lower expiratory flows; however, the association was significant only when infants were asymptomatic. CONCLUSION: This study shows that common colds cause a marked reduction of lung function in infants with RW.


Asunto(s)
Resfriado Común/fisiopatología , Pulmón/fisiopatología , Rhinovirus/patogenicidad , Resfriado Común/diagnóstico , Resfriado Común/epidemiología , Femenino , Humanos , Lactante , Pulmón/virología , Masculino , Exposición Materna , Intercambio Materno-Fetal , Embarazo , Recurrencia , Pruebas de Función Respiratoria , Ruidos Respiratorios , Factores de Riesgo , Fumar
10.
J Appl Microbiol ; 106(6): 1763-78, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19210567

RESUMEN

Microbial fructosyltransferases are polymerases that are involved in microbial fructan (levan, inulin and fructo-oligosaccharide) biosynthesis. Structurally, microbial fructosyltransferase proteins share the catalytic domain of glycoside hydrolases 68 family and are grouped in seven phylogenetically related clusters. Fructosyltransferase-encoding genes are organized in operons or in clusters associated with other genes related to carbohydrate metabolism or fructosyltransferase secretion. Fructosyltransferase gene expression is mainly regulated by two-component systems or phosphorelay mechanisms that respond to sucrose availability or other environmental signals. Microbial fructans are involved in conferring resistance to environmental stress such as water deprivation, nutrient assimilation, biofilm formation, and as virulence factors in colonization. As a result of the biological and industrial importance of fructans, fructosyltransferases have been the subject of extensive research, conducted to improve their enzymatic activity or to elucidate their biological role in nature.


Asunto(s)
Bacterias/enzimología , Fructanos/biosíntesis , Hexosiltransferasas/química , Hexosiltransferasas/genética , Bacterias/genética , Bacterias/metabolismo , Metabolismo de los Hidratos de Carbono , Regulación de la Expresión Génica , Operón
11.
Thorax ; 63(2): 167-71, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17901160

RESUMEN

BACKGROUND: Although global studies such as the International Study of Asthma and Allergies in Childhood (ISAAC) have provided valuable data on the prevalence of asthma in children in Latin America, there is little information on the relationship between asthma symptoms, pulmonary function, bronchial hyperresponsiveness (BHR) and atopy in the region. METHODS: This study examined the relationship between self-reported wheezing in the past 12 months, pulmonary function, airway responsiveness and atopy in children from a low income population in a neighbourhood of Santiago, Chile. Two random samples (100 each) of children aged 13-14 years who participated in ISAAC phase I were selected according to whether or not they reported wheezing in the past 12 months. Spirometry, the methacholine bronchial challenge test and the prick test were performed in all individuals. RESULTS: Children who reported current wheezing had significantly higher BHR to methacholine compared with those without wheezing (71.6% vs 52.6%; p = 0.007) and no significant difference was found in forced expiratory volume in 1 s (116.7 (12.3)% vs 120.3 (14.5%); p = 0.11). The prevalence of atopy was not significantly different between those children who reported wheezing compared with those who did not (44.2% vs 42.3%; p = 0.89). Multiple regression analysis showed that only BHR to methacholine (OR 2.72, 95% CI 1.25 to 4.13; p = 0.01) and maternal asthma (OR 3.1, 95% CI 1.2 to 8.3, p = 0.03) were significant risk factors for current wheezing. CONCLUSIONS: Our results support previous findings suggesting that in adolescents from underprivileged populations, self-reported current wheezing is related to BHR but not to atopy.


Asunto(s)
Hiperreactividad Bronquial/epidemiología , Adolescente , Asma/diagnóstico , Asma/epidemiología , Asma/fisiopatología , Hiperreactividad Bronquial/diagnóstico , Pruebas de Provocación Bronquial/métodos , Broncoconstrictores , Chile/epidemiología , Femenino , Humanos , Hipersensibilidad Inmediata/diagnóstico , Hipersensibilidad Inmediata/epidemiología , Renta , Masculino , Cloruro de Metacolina , Prevalencia , Ruidos Respiratorios/diagnóstico , Ruidos Respiratorios/etiología , Factores de Riesgo , Pruebas Cutáneas/métodos , Factores Socioeconómicos , Espirometría/métodos
12.
Scand J Immunol ; 67(2): 169-76, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18201371

RESUMEN

Bacterial internalization is an important process in the pathogenesis of infectious diseases in which nuclear factor kappaB (NF-kappaB) plays a prominent role. We present pharmacological evidence indicating that in bovine endothelial cells (BEC) the internalization of Staphylococcus aureus, a pathogenic bacterium that causes mastitis in bovine cattle, was associated with the activation of NF-kappaB. The internalization of S. aureus increased when BEC were stimulated with alpha-tumour necrosis factor (TNF-alpha) or beta-interleukin 1 (IL-1beta) which are known activators of NF-kappaB. SN50 (an inhibitor peptide of NF-kappaB nuclear translocation) and BAY 11-7083 (a chemical that inhibits the IkappaBalpha phosphorylation) caused significant reduction in S. aureus intracellular number, indicating that its internalization was associated with the NF-kappaB activity. Furthermore, specific inhibition of c-Jun N-terminal kinase with SP600125 (SP) or p-38 with SB203580 (SB) did not cause any change in the S. aureus intracellular number compared with the untreated control. Finally, TNF-alpha treatment of BEC after the addition of both SP and SB, induced a significant increase in S. aureus internalization above the control value. These data indicate that NF-kappaB activity is associated with S. aureus internalization and suggest that this transcription factor may play a role in the pathophysiology of bovine mastitis caused by this bacterium.


Asunto(s)
Interleucina-1beta/inmunología , Mastitis Bovina/microbiología , FN-kappa B/inmunología , Infecciones Estafilocócicas/veterinaria , Staphylococcus aureus/inmunología , Factor de Necrosis Tumoral alfa/inmunología , Animales , Antracenos/farmacología , Bovinos , Recuento de Colonia Microbiana , Células Endoteliales/efectos de los fármacos , Células Endoteliales/enzimología , Células Endoteliales/inmunología , Células Endoteliales/microbiología , Inhibidores Enzimáticos/farmacología , Femenino , Imidazoles , Interleucina-1beta/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas JNK Activadas por Mitógenos/inmunología , Mastitis Bovina/inmunología , Microscopía Electrónica/veterinaria , FN-kappa B/antagonistas & inhibidores , Nitrilos/farmacología , Péptidos/farmacología , Piridinas , Infecciones Estafilocócicas/inmunología , Infecciones Estafilocócicas/microbiología , Sulfonas/farmacología , Factor de Necrosis Tumoral alfa/farmacología
13.
J Clin Invest ; 107(2): 181-9, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11160134

RESUMEN

Serine/threonine phosphorylation of IRS-1 might inhibit insulin signaling, but the relevant phosphorylation sites are difficult to identify in cultured cells and to validate in isolated tissues. Recently, we discovered that recombinant NH2-terminal Jun kinase phosphorylates IRS-1 at Ser307, which inhibits insulin-stimulated tyrosine phosphorylation of IRS-1. To monitor phosphorylation of Ser307 in various cell and tissue backgrounds, we prepared a phosphospecific polyclonal antibody designated alphapSer307. This antibody revealed that TNF-alpha, IGF-1, or insulin stimulated phosphorylation of IRS-1 at Ser307 in 3T3-L1 preadipocytes and adipocytes. Insulin injected into mice or rats also stimulated phosphorylation of Ser307 on IRS-1 immunoprecipitated from muscle; moreover, Ser307 was phosphorylated in human muscle during the hyperinsulinemic euglycemic clamp. Experiments in 3T3-L1 preadipocytes and adipocytes revealed that insulin-stimulated phosphorylation of Ser307 was inhibited by LY294002 or wortmannin, whereas TNF-alpha-stimulated phosphorylation was inhibited by PD98059. Thus, distinct kinase pathways might converge at Ser307 to mediate feedback or heterologous inhibition of IRS-1 signaling to counterregulate the insulin response.


Asunto(s)
Factor I del Crecimiento Similar a la Insulina/farmacología , Insulina/farmacología , Proteínas Serina-Treonina Quinasas/química , Factor de Necrosis Tumoral alfa/farmacología , Animales , Anisomicina/farmacología , Células CHO , Cricetinae , Antagonistas de Insulina/farmacocinética , Resistencia a la Insulina , MAP Quinasa Quinasa 1 , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/metabolismo , Receptor de Insulina , Serina/química , Transducción de Señal , Tirosina/química
14.
Nat Commun ; 7: 11201, 2016 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-27062914

RESUMEN

Simulations predict that hot super-Earth sized exoplanets can have their envelopes stripped by photoevaporation, which would present itself as a lack of these exoplanets. However, this absence in the exoplanet population has escaped a firm detection. Here we demonstrate, using asteroseismology on a sample of exoplanets and exoplanet candidates observed during the Kepler mission that, while there is an abundance of super-Earth sized exoplanets with low incident fluxes, none are found with high incident fluxes. We do not find any exoplanets with radii between 2.2 and 3.8 Earth radii with incident flux above 650 times the incident flux on Earth. This gap in the population of exoplanets is explained by evaporation of volatile elements and thus supports the predictions. The confirmation of a hot-super-Earth desert caused by evaporation will add an important constraint on simulations of planetary systems, since they must be able to reproduce the dearth of close-in super-Earths.

15.
J Leukoc Biol ; 62(5): 661-6, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9365121

RESUMEN

Eotaxin is a potent chemoattractant for eosinophils during inflammation and allergic reactions in the adult, but its role during development has not been studied. We report that eotaxin and its receptor, CCR-3, are expressed by embryonic tissues responsible for blood development, including the yolk sac, fetal liver, and fetal blood. We also found that eotaxin acts synergistically with stem cell factor (SCF) to accelerate the differentiation of embryonic mast cell progenitors and to promote the growth of Mac-1+/Gr-1- cells from progenitors isolated at 10-12 days of gestation. This response is diminished by Pertussis toxin, the Gi alpha inhibitor. These studies suggest that eotaxin is involved in the growth of myeloid cell progenitors and the differentiation of mast cells during embryogenic development.


Asunto(s)
Quimiocinas CC , Citocinas/fisiología , Embrión de Mamíferos/citología , Células Madre Hematopoyéticas/citología , Animales , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Quimiocina CCL11 , Citocinas/biosíntesis , Endotelio/metabolismo , Femenino , Sangre Fetal/citología , Sangre Fetal/metabolismo , Técnica del Anticuerpo Fluorescente , Hígado/metabolismo , Masculino , Mastocitos/efectos de los fármacos , Mastocitos/fisiología , Ratones , Ratones Endogámicos C57BL , Fenotipo , ARN Mensajero/metabolismo , Receptores CCR3 , Receptores de Quimiocina/metabolismo , Factor de Células Madre/farmacología , Saco Vitelino/metabolismo
16.
Semin Arthritis Rheum ; 25(3): 203-13, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8650590

RESUMEN

In populations such as Northern Europeans in which the HLA-DR4 subtypes DW14 and Dw4 show strong association with rheumatoid arthritis (RA), these alleles and the double allelic dose of the shared epitope are considered severity markers. The clinical expression of RA varies in different populations, which may be determined by variation in the prevalence of these markers. In the present study we analyzed the expression of RA in 112 consecutive Chilean patients and its relation to the prevalence of genetic factors, prompted by our previous observation that DR4 is weakly associated to RA in this population. Mean age was 50 +/- 14 years; 90% were seropositive and 87% were female, with a disease duration of 10 +/- 8 years. Extra-articular manifestations were found in 38% of patients, rheumatoid nodules in 27%, vasculitis in 8%, and Sjogren's syndrome in 29%. Functional capacity (ACR, 1991) I or II: 82%.15% of patients stopped working. Hand radiographs scored according to Steinbrocker in 89 patients: I, 21%; II, 15%; III, 43%; IV, 21%. In this series, patients with less formal education seemed to have more benign arthritis. In 97 controls and in 65 (56%) RA patients the presence of DRB1 alleles corresponding to DR1 and DR4 serotypes, to DR4-Dw subtypes, and homozygocity, were determined by polymerase chain reaction followed by specific oligonucleotide hybridization. The shared epitope was present in 53% of RA patients and in 30% of controls (P = .0048, odds ratio [OR] = 2.64). A double allelic dose of the epitope was present in 15% of RA patients compared with 4% of controls (P = .026, OR = 4.23). In a subgroup of 31 erosive RA patients we did not find a significant association of disease severity with the shared epitope in a single or double allelic dose. None of the DR4 subtypes that associate with RA in other populations was found significantly more prevalent in our patients. The severity of RA in our study compared with published series was intermediate between British patients with severe RA and Greek patients with milder disease. This may be due to the high prevalence of Dwl3*0403 in our population.


Asunto(s)
Artritis Reumatoide/epidemiología , Artritis Reumatoide/inmunología , Adulto , Factores de Edad , Edad de Inicio , Anciano , Anciano de 80 o más Años , Chile/epidemiología , Escolaridad , Femenino , Antígenos HLA-D/sangre , Antígeno HLA-DR4/sangre , Prueba de Histocompatibilidad , Homocigoto , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Pronóstico , Factores Sexuales , Factores de Tiempo , Trabajo
17.
Pediatr Pulmonol ; 32(6): 447-52, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11747248

RESUMEN

Many pharmaceutical companies sell salbutamol in metered-dose inhalers (MDI) for the treatment of asthma. However, the therapeutic equivalence of the more recently released generic products has not been compared with the original patented product in children. Twenty children with mild to moderate asthma, presently asymptomatic and with normal lung function, were randomly allocated to receive 200 microg of inhaled salbutamol (Albuterol) from three MDIs prepared by different manufacturers: the original Glaxo product and two generic products. The three drug formulations and placebo were given 10 min before a methacholine challenge test to determine the degree of protection provided against methacholine-induced bronchoconstriction (MIB) by each salbutamol aerosol. Tests were performed on 4 consecutive days. Doubling concentrations of methacholine were inhaled until the forced expired volume in 1 sec (FEV(1)) decreased by 20% from its baseline value. Compared to placebo, all patients increased significantly the provocation concentration that decreased FEV(1) by 20% (PC(20)) by more than one doubling concentration after inhaling each of the three salbutamol aerosols. The effectiveness was not significantly different between medications (P = 0.8). There was a small but significant difference among MDIs in aerosol particle size and total and fine-particle dose released per actuation. However, no relation was found between aerosol particle size or released dose and the protective effect. This study shows that the three tested brands of salbutamol MDI protected asthmatic children equally from MIB. When prescribing these salbutamol MDIs to prevent symptoms triggered by nonspecific stimuli in asthmatic children, the selection may be based on cost-benefit criteria.


Asunto(s)
Albuterol/farmacocinética , Asma/tratamiento farmacológico , Nebulizadores y Vaporizadores , Adolescente , Albuterol/administración & dosificación , Asma/fisiopatología , Pruebas de Provocación Bronquial , Broncoconstricción , Broncoconstrictores , Niño , Estudios Cruzados , Método Doble Ciego , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , Cloruro de Metacolina , Tamaño de la Partícula , Espirometría , Equivalencia Terapéutica
18.
Acta Ortop Mex ; 27(2): 128-32, 2013.
Artículo en Español | MEDLINE | ID: mdl-24701766

RESUMEN

The total shoulder prosthesis in reverse was designed as a treatment for patients with arthropathy deficiency rotator cuff because the conservative treatment failed. The indications for its use have evolved; these include arthropathy deficient rotator cuff, reconstruction humeral head fractures, hemiarthroplasties revision and reconstruction after tumor resection. Successful placement depends on the patient having a function adequately and good quality deltoid in the glenoid bone and in the proximal humerus. Until a few years ago data was no clear on the success of this procedure, currently encouraging results have been reported, however, they have had a high cost due to the high rate of complications, which are divided into specific and common to the prosthesis shoulder surgeries. The primary objective of this review is to assess the most common complications of the prosthesis in reverse, how to treat them and how we can avoid them.


Asunto(s)
Artroplastia/métodos , Complicaciones Posoperatorias/etiología , Diseño de Prótesis , Articulación del Hombro/cirugía , Tornillos Óseos , Remoción de Dispositivos , Humanos , Inestabilidad de la Articulación/etiología , Inestabilidad de la Articulación/prevención & control , Selección de Paciente , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Falla de Prótesis/etiología , Infecciones Relacionadas con Prótesis/etiología , Infecciones Relacionadas con Prótesis/prevención & control , Resultado del Tratamiento
19.
J Med Microbiol ; 62(Pt 3): 369-376, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23139397

RESUMEN

Rapid isolation and identification of pathogens is a major goal of diagnostic microbiology. In order to isolate and identify Staphylococcus aureus, a number of authors have used a variety of selective and/or differential culture media. However, to date, there are no reports comparing the efficacy of selective and differential culture media for S. aureus isolation from bovine mastitis cases using the 16S rRNA (rrs) gene sequence as a gold standard test. In the present study, we evaluated the efficacy of four selective and/or differential culture media for the isolation of S. aureus from milk samples collected from cows suffering from bovine mastitis. Four hundred and forty isolates were obtained using salt-mannitol agar (SMA, Bioxon), Staphylococcus-110 agar (S110, Bioxon), CHROMAgar Staph aureus (CSA, BD-BBL) and sheep's blood agar (SBA, BD-BBL). All bacterial isolates were identified by their typical colony morphology in the respective media, by secondary tests (for coagulase and ß-haemolysis) and by partial 16S rRNA (rrs) gene sequencing as a gold standard test. Sensitivity, positive predictive and negative predictive values were higher for SMA (86.96, 52.63 and 95.95%, respectively) compared with S110 (70.00, 23.73 and 90.91%, respectively), CSA (69.23, 28.13 and 95.74%, respectively) and SBA (68.75, 37.93 and 89.58%, respectively) while specificity values were similar for all media. Data indicated that the use of culture media for S. aureus isolation combined with determination of coagulase activity and haemolysis as secondary tests improved accuracy of the identification and was in accordance with rrs gene sequence-analysis compared with the use of the culture media alone.


Asunto(s)
Medios de Cultivo/química , Mastitis Bovina/microbiología , Infecciones Estafilocócicas/veterinaria , Staphylococcus aureus/clasificación , Staphylococcus aureus/aislamiento & purificación , Animales , Técnicas Bacteriológicas/veterinaria , Bovinos , Femenino , Datos de Secuencia Molecular , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Infecciones Estafilocócicas/microbiología
20.
Science ; 332(6026): 213-6, 2011 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-21474754

RESUMEN

In addition to its search for extrasolar planets, the NASA Kepler mission provides exquisite data on stellar oscillations. We report the detections of oscillations in 500 solar-type stars in the Kepler field of view, an ensemble that is large enough to allow statistical studies of intrinsic stellar properties (such as mass, radius, and age) and to test theories of stellar evolution. We find that the distribution of observed masses of these stars shows intriguing differences to predictions from models of synthetic stellar populations in the Galaxy.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA