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1.
Ann Oncol ; 30(10): 1638-1646, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31400196

RESUMEN

BACKGROUND: Accurate prognostic stratification of human papillomavirus-associated oropharyngeal cancers (HPV+OPSCC) is required to identify patients potentially suitable for treatment deintensification. We evaluated the prognostic significance of CD103, a surface marker associated with tissue-resident memory T cells (TRMs), in two independent cohorts of patients with HPV+OPSCC. PATIENTS AND METHODS: The abundance and distribution of CD103+ immune cells were quantified using immunohistochemistry in a cohort of 189 HPV+OPSCC patients treated with curative intent and correlated with outcome. Findings were then validated in an independent cohort comprising 177 HPV+OPSCCs using univariable and multivariable analysis. Intratumoral CD103+ immune cells were characterized by multispectral fluorescence immunohistochemistry and gene expression analysis. RESULTS: High intratumoral abundance of CD103+ immune cells using a ≥30% cut-off was found in 19.8% of tumors in the training cohort of HPV+OPSCC patients and associated with excellent prognosis for overall survival (OS) with adjusted hazard ratio (HR) of 0.13 [95% confidence interval (CI) 0.02-0.94, P = 0.004]. In the independent cohort of HPV+OPSCCs, 20.4% had high intratumoral CD103+ abundance and an adjusted HR for OS of 0.16 (95% CI 0.02-1.22, P = 0.02). Five year OS of patients with high intratumoral CD103 was 100% across both cohorts. The C-statistic for the multivariate prognostic model with stage and age was significantly improved in both cohorts with the addition of intratumoral CD103+ cell abundance. On the basis of spatial location, co-expression of CD8 and CD69, and gene expression profiles, intratumoral CD103+ cells were consistent with TRMs. CONCLUSION: Quantification of intratumoral CD103+ immune cell abundance provides prognostic information beyond that provided by clinical parameters such as TNM-staging, identifying a population of low risk HPV+OPSCC patients who are good candidates for trials of deintensification strategies.


Asunto(s)
Antígenos CD/inmunología , Biomarcadores de Tumor/análisis , Carcinoma de Células Escamosas/inmunología , Memoria Inmunológica/inmunología , Cadenas alfa de Integrinas/inmunología , Neoplasias Orofaríngeas/inmunología , Infecciones por Papillomavirus/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Antígenos CD/metabolismo , Biomarcadores de Tumor/inmunología , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/virología , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Cadenas alfa de Integrinas/metabolismo , Masculino , Persona de Mediana Edad , Neoplasias Orofaríngeas/patología , Neoplasias Orofaríngeas/terapia , Neoplasias Orofaríngeas/virología , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/virología , Pronóstico , Estudios Prospectivos , Estudios Retrospectivos , Tasa de Supervivencia , Adulto Joven
2.
Ann Oncol ; 30(8): 1321-1328, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31125062

RESUMEN

BACKGROUND: Anti-PD1/PD-L1 directed immune checkpoint inhibitors (ICI) are widely used to treat patients with advanced non-small-cell lung cancer (NSCLC). The activity of ICI across NSCLC harboring oncogenic alterations is poorly characterized. The aim of our study was to address the efficacy of ICI in the context of oncogenic addiction. PATIENTS AND METHODS: We conducted a retrospective study for patients receiving ICI monotherapy for advanced NSCLC with at least one oncogenic driver alteration. Anonymized data were evaluated for clinicopathologic characteristics and outcomes for ICI therapy: best response (RECIST 1.1), progression-free survival (PFS), and overall survival (OS) from ICI initiation. The primary end point was PFS under ICI. Secondary end points were best response (RECIST 1.1) and OS from ICI initiation. RESULTS: We studied 551 patients treated in 24 centers from 10 countries. The molecular alterations involved KRAS (n = 271), EGFR (n = 125), BRAF (n = 43), MET (n = 36), HER2 (n = 29), ALK (n = 23), RET (n = 16), ROS1 (n = 7), and multiple drivers (n = 1). Median age was 60 years, gender ratio was 1 : 1, never/former/current smokers were 28%/51%/21%, respectively, and the majority of tumors were adenocarcinoma. The objective response rate by driver alteration was: KRAS = 26%, BRAF = 24%, ROS1 = 17%, MET = 16%, EGFR = 12%, HER2 = 7%, RET = 6%, and ALK = 0%. In the entire cohort, median PFS was 2.8 months, OS 13.3 months, and the best response rate 19%. In a subgroup analysis, median PFS (in months) was 2.1 for EGFR, 3.2 for KRAS, 2.5 for ALK, 3.1 for BRAF, 2.5 for HER2, 2.1 for RET, and 3.4 for MET. In certain subgroups, PFS was positively associated with PD-L1 expression (KRAS, EGFR) and with smoking status (BRAF, HER2). CONCLUSIONS: : ICI induced regression in some tumors with actionable driver alterations, but clinical activity was lower compared with the KRAS group and the lack of response in the ALK group was notable. Patients with actionable tumor alterations should receive targeted therapies and chemotherapy before considering immunotherapy as a single agent.


Asunto(s)
Antineoplásicos Inmunológicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos Inmunológicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/inmunología , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Femenino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Mutación , Oncogenes/genética , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/inmunología , Supervivencia sin Progresión , Sistema de Registros/estadística & datos numéricos , Criterios de Evaluación de Respuesta en Tumores Sólidos , Estudios Retrospectivos
4.
Opt Express ; 21(25): 31390-4, 2013 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-24514713

RESUMEN

We report on a dual output all-PM fiber laser system running at 100 MHz repetition rate offering coherent broadband and narrowband pulses centered at 2.05 µm with a spectral FWHM bandwidth of 60 nm and 1.5 nm at up to 360 mW and 500 mW, respectively. The broadband pulses are compressed down to 135 fs. The multi-stage double-clad amplifier based on Tm/Ho codoping is seeded by a supercontinuum light source, spanning from around 1 µm up to 2.4 µm.

5.
Diabet Med ; 29(7): 911-7, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22283416

RESUMEN

AIMS: To study whether HbA(1c) , and its relationship with fasting plasma glucose, was significantly different among Chinese, Malays and Indians in Singapore. METHODS: A sample of 3895 individuals without known diabetes underwent detailed interview and health examination, including anthropometric and biochemical evaluation, between 2004 and 2007. Pearson's correlation, analysis of variance and multiple linear regression analyses were used to examine the influence of ethnicity on HbA(1c) . RESULTS: As fasting plasma glucose increased, HbA(1c) increased more in Malays and Indians compared with Chinese after adjustment for age, gender, waist circumference, serum cholesterol, serum triglyceride and homeostasis model assessment of insulin resistance (P-interaction < 0.001). This translates to an HbA(1c) difference of 1.1 mmol/mol (0.1%, Indians vs. Chinese), and 0.9 mmol/mol (0.08%, Malays vs. Chinese) at fasting plasma glucose 5.6 mmol/l (the American Diabetes Association criterion for impaired fasting glycaemia); and 2.1 mmol/mol (0.19%, Indians vs. Chinese) and 2.6 mmol/mol (0.24%, Malays vs. Chinese) at fasting plasma glucose 7.0 mmol/l, the diagnostic criterion for diabetes mellitus. CONCLUSIONS: Using HbA(1c) in place of fasting plasma glucose will reclassify different proportions of the population in different ethnic groups. This may have implications in interpretation of HbA(1c) results across ethnic groups and the use of HbA(1c) for diagnosing diabetes mellitus.


Asunto(s)
Pueblo Asiatico , Glucemia/metabolismo , Colesterol/sangre , Diabetes Mellitus Tipo 2/sangre , Ayuno/metabolismo , Triglicéridos/sangre , Población Blanca , China/etnología , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/etnología , Femenino , Humanos , India/etnología , Resistencia a la Insulina , Malasia/etnología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Factores de Riesgo , Singapur/epidemiología , Encuestas y Cuestionarios , Circunferencia de la Cintura
6.
Opt Lett ; 36(19): 3918-20, 2011 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-21964141

RESUMEN

An all-optical and passively carrier-to-envelope-phase-stabilized (CEP-stabilized) optical parametric chirped pulse amplification (OPCPA) system is demonstrated with sub-250-mrad CEP stability over 11 min and better than 100 mrad over 11 s. This is achieved without any electronic CEP stabilization loop for 160 kHz pulse repetition rate in the few cycle regime.

7.
Opt Lett ; 35(19): 3204-6, 2010 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-20890334

RESUMEN

We report on the shortest pulses to date from a mid-IR optical parametric chirped pulse amplification: 67 fs duration with 3.8 µJ energy operating at 3.2 µm. The system is all solid state and diode pumped and operates at 100 kHz with unprecedented power stability of 0.75%rms over 30 min.

8.
Lung Cancer ; 129: 22-27, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30797487

RESUMEN

OBJECTIVES: There has been evidence of an association between patient outcomes and the number of surgeries performed at a hospital. To our knowledge, there are no Australian data on hospital cancer surgery volumes and patient outcomes. We evaluated the relationship between hospital non-small cell lung cancer (NSCLC) surgery volume and patient outcomes in Victoria. MATERIALS AND METHODS: Patients with a primary diagnosis of NSCLC between 2008 and 2014 were identified in the Victorian Cancer Registry (n = 15,369), 3,420 (22%) of whom had lung cancer surgery. Primary outcome was death within 90 days of surgery and secondary outcomes included overall survival, use of postoperative ventilation and ≥24hours spent in ICU. Hospital volume was measured as the average number of lung surgeries performed per year, with quartiles Q1: 1-17, Q2: 18-34, Q3: 35-58 and Q4: 59 + . RESULTS: 57% (1,941/3,420) lung cancer patients underwent lobectomy, 38% (1,299/3,420) sub-lobar resection and 5% (180/3,420) pneumonectomy. The overall 90-day mortality after lung surgery was 3.5%, and was 2.6% and 4.5% for patients undergoing lobectomy and sub-lobar resection respectively. There was no difference in 90-day mortality and overall survival between low- and high-volume centres regardless of procedure. Patients operated on in lower volume centres had more admissions to ICU ≥24hours (Q1. 55% vs. Q4. 11%, p-trend <0.001). A higher proportion of patients attending private hospitals (19%) had an ASA score of 4 compared with patients attending a public hospital (9%). CONCLUSION: We observed no evidence of survival differences between lung cancer patients attending low- and high-volume hospitals for cancer surgery. A higher proportion of patients had an ICU admission ≥24hours in lower volume centres and there are a higher proportion of patients with an ASA score of 4 in private hospitals compared to public hospitals.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/epidemiología , Hospitales de Alto Volumen , Neoplasias Pulmonares/epidemiología , Neumonectomía/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Australia/epidemiología , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Femenino , Hospitalización , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/cirugía , Masculino , Persona de Mediana Edad , Análisis de Supervivencia , Resultado del Tratamiento
9.
Mol Cell Biol ; 19(5): 3474-84, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10207071

RESUMEN

We previously reported that the activation of the M promoter of the human choline acetyltransferase (ChAT) gene by butyrate and trapoxin in transfected CHP126 cells is blocked by PD98059, a specific mitogen-activated protein kinase kinase (MEK) inhibitor (E. Espinos and M. J. Weber, Mol. Brain Res. 56:118-124, 1998). We now report that the transcriptional effects of histone deacetylase inhibitors are mediated by an H7-sensitive serine/threonine protein kinase. Activation of the ChAT promoter by butyrate and trapoxin was blocked by 50 microM H7 in both transient- and stable-transfection assays. Overexpression of p300, a coactivator protein endowed with histone acetyltransferase activity, stimulated the ChAT promoter and had a synergistic effect on butyrate treatment. These effects were blocked by H7 and by overexpressed adenovirus E1A 12S protein. Moreover, both H7 and PD98059 suppressed the activation of the Rous sarcoma virus (RSV) and simian virus 40 promoters by butyrate in transfection experiments. Similarly, the induction of the cellular histone H1(0) gene by butyrate in CHP126 cells was blocked by H7 and by PD98059. Previous data (L. Cuisset, L. Tichonicky, P. Jaffray, and M. Delpech, J. Biol. Chem. 272:24148-24153, 1997) showed that the induction of the H1(0) gene by butyrate is blocked by okadaic acid, an inhibitor of protein phosphatases. We now show that the activation of the ChAT and RSV promoters by butyrate in transfected CHP126 cells is also blocked by 200 nM okadaic acid. Western blotting and in vivo metabolic labeling experiments showed that butyrate has a biphasic effect on histone H3 phosphorylation, i.e., depression for up to 16 h followed by stimulation. The data thus strongly suggest that the transcriptional effects of histone deacetylase inhibitors are mediated through the activation of MEK1 and of an H7-sensitive protein kinase in addition to protein phosphatases.


Asunto(s)
Regulación de la Expresión Génica/genética , Péptidos , Proteínas Serina-Treonina Quinasas/genética , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/farmacología , Acetilación , Acetiltransferasas/genética , Proteínas E1A de Adenovirus/genética , Antibacterianos/farmacología , Butiratos/farmacología , Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , Línea Celular , Colina O-Acetiltransferasa/genética , Inhibidores Enzimáticos/farmacología , Flavonoides/farmacología , Genes Reporteros/genética , Histona Acetiltransferasas , Inhibidores de Histona Desacetilasas , Histonas/genética , Humanos , Ácido Ocadaico/farmacología , Fosforilación , Regiones Promotoras Genéticas/genética , Factores de Transcripción , Activación Transcripcional/efectos de los fármacos , Transfección , Factores de Transcripción p300-CBP
10.
Ann Acad Med Singap ; 34(3): 271-4, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15902349

RESUMEN

INTRODUCTION: At times, it may be difficult to differentiate early stage, low-grade adrenocortical carcinoma from benign adrenal adenoma. CLINICAL PICTURE: A 53-year-old lady underwent right adrenalectomy for a 4-cm adrenocortical tumour causing Cushing's syndrome. Histology revealed an adrenocortical adenoma. Sixteen years later, she presented with a 14-cm adrenal tumour, again on the right side. TREATMENT: She underwent surgical removal of the tumour. Histology confirmed adrenocortical carcinoma. OUTCOME: She died of metastatic disease 17 months later. CONCLUSIONS: This case highlights the importance of long-term, systematic follow-up of patients treated for benign adrenal adenomas, especially if the tumour size exceeds 4 cm.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/patología , Carcinoma Corticosuprarrenal/patología , Síndrome de Cushing/etiología , Recurrencia Local de Neoplasia/patología , Neoplasias de la Corteza Suprarrenal/complicaciones , Neoplasias de la Corteza Suprarrenal/cirugía , Adenoma Corticosuprarrenal/patología , Carcinoma Corticosuprarrenal/complicaciones , Carcinoma Corticosuprarrenal/secundario , Carcinoma Corticosuprarrenal/cirugía , Diagnóstico Diferencial , Resultado Fatal , Femenino , Humanos , Persona de Mediana Edad
12.
Sci Rep ; 5: 7584, 2015 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-25579608

RESUMEN

We investigated nonlinear photoemission from plasmonic films with femtosecond, mid-infrared pulses at 3.1 µm wavelength. Transition between regimes of multi-photon-induced and tunneling emission is demonstrated at an unprecedentedly low intensity of <1 GW/cm(2). Thereby, strong-field nanophysics can be accessed at extremely low intensities by exploiting nanoscale plasmonic field confinement, enhancement and ponderomotive wavelength scaling at the same time. Results agree well with quantum mechanical modelling. Our scheme demonstrates an alternative paradigm and regime in strong-field physics.

13.
Hum Immunol ; 60(9): 894-900, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10527399

RESUMEN

Singaporean Chinese with insulin-dependent diabetes mellitus (IDDM) have previously been shown to be associated with the DRB1*0301 haplotype and the joint occurrence of DRB1*0301/*0901 and DRB1*0301/*04. The present study extended previous HLA associations by investigating the HLA region using four microsatellites (TNFa, D6S273, TAP1, DQCARII). Seventy-five IDDM patients and 80 healthy controls were studied. TNFa*3 (RR = 2.26), TNFa*12 (RR = 3.30), TAP1*9 (RR = 2.55) showed increased frequencies while TNFa*11 (RR = 0.29), TAP1*4 (RR = 0.50) showed decreased frequencies in patients compared to controls. Linkage analysis suggested that the positive associations of TNFa*3 and TAP1*9 were secondary to that of DRB1*0301. However, TNFa*12 appeared to provide additional risks to IDDM besides the DRB1*0301 haplotype, whereas TNFa*11 and TAP1*4 conferred an independent protective effect against IDDM. Our findings reinforce the notion that susceptibility to and protection against IDDM may include TNF region. In the present study, TNFa*12 seemed to be the primary association in the DRB1*0405 haplotype and may play an independent role in the pathogenesis of IDDM through TNF-alpha function.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Diabetes Mellitus Tipo 1/genética , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Repeticiones de Microsatélite , Factor de Necrosis Tumoral alfa/genética , Transportador de Casetes de Unión a ATP, Subfamilia B, Miembro 2 , Alelos , Pueblo Asiatico , China/etnología , Diabetes Mellitus Tipo 1/inmunología , Cadenas beta de HLA-DQ , Cadenas HLA-DRB1 , Humanos , Singapur
14.
Hum Immunol ; 44(3): 175-80, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8666554

RESUMEN

IDDM in Singaporean Chinese was associated with HLA B58, DRB1*0301, DQB1*0201, and joint occurrences of DRB1*0301/*0901 and DRB1*0301/*04. Of the DR4s the frequencies of DRB1*0401, *0404, and *0405 were higher and *0406 was lower in patients compared to controls. DRB1*0301/*0901 was observed mainly in female patients and the frequency showed an inverse relationship with age at onset, whereas DRB1*0301/*04 was observed mainly in male patients and also showed an inverse relationship with age at onset. DRB1*1202 showed an increasing frequency with age at onset. IDDM patients had a higher frequency of homozygous NAsp57 DQ beta chains and a lower frequency of homozygous Asp57 DQ beta chains compared to controls, especially in younger onset patients.


Asunto(s)
Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/fisiopatología , Antígenos HLA/genética , Adolescente , Adulto , Factores de Edad , Anciano , Alelos , Pueblo Asiatico/genética , Niño , Preescolar , Diabetes Mellitus Tipo 1/inmunología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales
15.
Autoimmunity ; 15(4): 305-9, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8136459

RESUMEN

Islet cell antibodies (ICAs) in Chinese (23 IDDM, 13 NIDDM and 6 non-diabetic) were characterized for immunoglobulin isotypes and light chain specificity. All ICAs were IgG-type and none were IgM- or IgA-type (median titre: 20 JDF units; range 10-160). Light chain specificity showed that 25/36 (69.4%) of the diabetic patients had lambda and kappa chains. Half of the non-diabetic subjects had both lambda and kappa chains. The rest had only lambda chains. Isotyping for ICA-IgG subclass combination with IUIS/WHO reference monoclonal antibodies in the diabetic patients gave the following: IgG1 alone-9 (25%), IgG1+2+3-8 (22.2%), IgG1+2-11 (30.6%), IgG1+3-6 (16.7%), IgG2+3-2 (5.6%). No ICA-IgG4 was detected. The frequency of the subclasses would be: IgG1-94.4%, IgG2-58.3% and IgG3-44.4%. The distribution of ICA-IgG subclasses was not affected by diabetes type (IDDM or NIDDM) or duration of disease. Of the 6 non-diabetic subjects only one had a single ICA-IgG subclass (IgG1). Serum levels of IgG subclasses in a subgroup of the patients (n = 16) were not significantly different from normal individuals. Biochemical modification of pancreatic tissue prior to ICA testing showed that acetylneuraminic acid residues, lipid and protein components were associated with binding of ICAs. The co-existence of other autoantibodies was also tested in these 42 ICA-positive sera. Twelve individuals (1 non-diabetic) had thyroid autoantibodies. Antibodies to thyrotrophin receptor, gastric parietal cell and rheumatoid factor were not detected.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Autoanticuerpos/genética , Diabetes Mellitus/etnología , Diabetes Mellitus/inmunología , Isotipos de Inmunoglobulinas/genética , Islotes Pancreáticos/inmunología , Adolescente , Adulto , Pueblo Asiatico , Autoanticuerpos/sangre , Autoanticuerpos/clasificación , Niño , Femenino , Humanos , Isotipos de Inmunoglobulinas/sangre , Isotipos de Inmunoglobulinas/clasificación , Masculino , Persona de Mediana Edad , Glándula Tiroides/inmunología
16.
Autoimmunity ; 35(2): 119-24, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12073931

RESUMEN

Type 1 diabetes in most Asian populations may not have a salient autoimmune basis when assessed with single determinations of the major markers, islet cell antibodies (ICAs) and glutamic acid decarboxylase antibodies (GAD65ab). With the inclusion of antibodies to tyrosine phosphatase-like protein IA-2 (IA-2ab) as an additional major marker, we re-examined autoimmune diabetes in a group of Chinese patients. We studied 272 subjects at various stages of disease with blood samples procured for biochemical analysis. ICAs were measured by immunofluorescence, GAD65ab and IA-2ab by radioimmunoassay. Sixty-seven patients fulfilled clinical diagnosis of type 1 diabetes and the remaining 205 patients were type 2. Prevalence of single autoantibody type in recent-onset type 1 diabetes ( < 1 year duration; n = 47) showed 10.6% with ICAs, 44.7% GAD65ab and 36.2% IA-2ab. GAD65ab account for more than two-thirds of the markers found in type 1 diabetes. Combined analysis further showed that 51.1% had at least one antibody type, 31.9% with two or more antibodies and 8.5% with all three antibodies. Islet autoimmunity presence in childhood-onset type 1 diabetes improved with the addition of IA-2ab, though less impact was seen in the adult-onset. Similarly, combined analysis for type 2 patients with recent diabetes showed a modest increase to 13% with islet autoimmunity compared to 8% when assessed by GAD65ab alone. Combining IA-2ab and GAD65ab assays results detected slightly more immune-mediated diabetes, compared to using a single GAD65ab determination. Non-autoimmune causes need to be considered in the pathogenesis of type 1 diabetes in Chinese, particularly in adults.


Asunto(s)
Autoanticuerpos/inmunología , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 2/inmunología , Glutamato Descarboxilasa/inmunología , Isoenzimas/inmunología , Proteínas Tirosina Fosfatasas/inmunología , Adulto , Pueblo Asiatico , Autoanticuerpos/sangre , Niño , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/enzimología , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/enzimología , Femenino , Glutamato Descarboxilasa/metabolismo , Humanos , Isoenzimas/metabolismo , Masculino , Proteína Tirosina Fosfatasa no Receptora Tipo 1 , Proteínas Tirosina Fosfatasas/metabolismo , Proteínas Tirosina Fosfatasas Clase 8 Similares a Receptores
17.
Brain Res Mol Brain Res ; 17(3-4): 227-38, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8510497

RESUMEN

We have cloned the 5' region of human aromatic L-amino acid decarboxylase (AADC) gene in a cosmid and an overlapping lambda clone, and sequenced the first five exons. A 61 base pair (bp) non-coding, first exon containing for the 5' end of a human pheochromocytoma AADC cDNA was localized 16 kb upstream of exon 2, in which translation is initiated. The transcription start site was localized by RNAse mapping, primer extension and reverse transcription-PCR. The non-conventional cap site was preceded by a modified TATA box at position -29. A strong promoter was characterized in the 560 bp region upstream of the cap site by linkage to the reporter gene LacZ, and transfection in human neuroblastoma SK-N-BE and SK-N-BE-K2 cells. Using a series of constructs bearing a varying length of 5' flanking region, three positive regulatory elements have been localized in the -560 to -394, -244 to -200 and -147 to -1 regions. Negative regulatory elements were localized in the -9000 to -560 and -394 to -316 regions. Surprisingly, constructs comprising all or the major part of intron 1 were inactive, suggesting the presence of a silencer in the first intron, or incorrect splicing events. The construct containing 560 bp of 5' flanking sequence did not express in human cholinergic neuroepithelioma cells MC-I-XC, and in three non-neuronal cell lines which displayed high AADC activities: human pancreatic carcinoma cells AsPC-1, rat insulinoma cells RINm5F and mouse anterior pituitary cells AtT20. These data suggest that we have identified a neuron-specific AADC promoter. An extensive search for a second promoter responsible for AADC gene expression in non-neuronal cells only gave negative results.


Asunto(s)
Descarboxilasas de Aminoácido-L-Aromático/genética , Regulación Enzimológica de la Expresión Génica/fisiología , Neuronas/fisiología , Regiones Promotoras Genéticas , Transcripción Genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Línea Celular , Clonación Molecular , Humanos , Datos de Secuencia Molecular , Células Tumorales Cultivadas
18.
Brain Res Mol Brain Res ; 56(1-2): 227-37, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9602135

RESUMEN

The neuronal promoter of human aromatic l-amino acid decarboxylase gene has been analysed to elucidate the mechanisms of neuron type-specific expression. The (-560/+92) promoter segment was sufficient to direct luciferase expression at a higher level in SK-N-BE neuroblastoma cells, than in CHP126 neuroepithelia, HepG2 hepatoma or SK-Hep1 epithelioma cells. Deletions experiments showed that this segment contained a neuronal-specific (element T1) and a SK-N-BE-specific (element N1) cis-activating sequences. Element T1 (-72/-36) bound Sp1 and NF-Y proteins, and unidentified neuronal-specific factors. Element N1 (-102/-72) bound cell-specific factors, identified as HNF-3, N-Oct-3/Brn-2 and N-Oct-2. HNF-3 proteins recognized the sequence TCAGTAAATA that matches the consensus motif. Oct-1, N-Oct-2 and N-Oct-3 bound the AAATAATGC sequence that overlaps the HNF-3 binding site. In addition, we show that the HNF-3 binding sites from aldolase C and HNF-3beta gene promoters also bind N-Oct-2 and N-Oct-3 proteins. These data suggest a functional interplay of winged helix/forkhead and POU-domain transcription factors on a variety of neuronal gene promoters.


Asunto(s)
Descarboxilasas de Aminoácido-L-Aromático/genética , Proteínas de Unión al ADN/metabolismo , Secuencias Hélice-Asa-Hélice , Neuronas/metabolismo , Proteínas Nucleares/metabolismo , Regiones Promotoras Genéticas/genética , Factores de Transcripción/metabolismo , Animales , Sitios de Unión/genética , Células COS , Proteínas de Unión al ADN/fisiología , Factor Nuclear 3-alfa del Hepatocito , Factor Nuclear 3-beta del Hepatocito , Factor Nuclear 3-gamma del Hepatocito , Proteínas de Homeodominio , Humanos , Neuronas/citología , Proteínas Nucleares/fisiología , Factores del Dominio POU , Factores de Transcripción/fisiología , Células Tumorales Cultivadas
19.
Int J Epidemiol ; 21(3): 473-7, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1634308

RESUMEN

This study was a cross-sectional random survey of the whole of Singapore, based on 2143 subjects (aged 18-69 years, response rate 60.3%). The presence of corneal arcus was determined by a doctor using the naked eye in good light. Cardiovascular risk factors were measured by standardized techniques. The prevalence rates overall of corneal arcus were: 18-29 years (males 0.5%, females 0.3%), 30-49 years (males 18.1%, females 13.3%) and 50-69 years (males 70.7%, females 55.3%). In the 30-49 age group, people with arcus had higher serum low density lipoprotein (LDL) cholesterol concentrations than people without arcus, the mean differences being, males 0.31 mmol/l (P = 0.040) and females 0.62 mmol/l (P less than 0.001) with an increased likelihood of having values greater than 5.5.mmol/l of males 1.8 (95% confidence interval (95% CI): 1.0-3.4) and females 2.6 (95% CI: 1.4-4.8). There were no significant differences for LDL-cholesterol in the 50-69 age group. Arcus was weakly associated with fasting plasma glucose in the 30-49 age group. Arcus was not associated with serum high density lipoprotein (HDL) cholesterol, serum fasting triglyceride, blood pressure and cigarette smoking. It is concluded that while corneal arcus is primarily an age-related change, its formation is accelerated by high serum LDL-cholesterol so that in people under 50 years it is a marker for the condition.


Asunto(s)
Arco Senil/epidemiología , Enfermedad Coronaria/epidemiología , Adolescente , Adulto , Factores de Edad , Anciano , Arco Senil/etnología , China/etnología , Enfermedad Coronaria/etnología , Femenino , Humanos , India/etnología , Malasia/etnología , Masculino , Persona de Mediana Edad , Prevalencia , Factores Sexuales , Singapur/epidemiología
20.
J Physiol Paris ; 88(4): 215-27, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7874082

RESUMEN

The promoter regions of human choline acetyltransferase (ChAT) and aromatic L-amino acid decarboxylase (AADC) genes have been analyzed by transient transfection assays. AADC gene is transcribed from two alternative noncoding first exons, 1N and 1NN, expressed in pheochomocytoma and hepatoma cells, respectively. 5' flanking sequences of exon 1 N (from 9000 to 147 bp) display promoter activity in SK-N-BE neuroblastoma cells, but not in MC-I-XC cholinergic neuroepithelioma cells, and in AADC-rich non-neuronal cells. On the contrary, 5' flanking sequences of exon 1 NN (from 1117 to 119 bp) display high promoter activity in human hepatoma cells HepG2, but not in SK-N-BE cells, suggesting high degrees of specificity of promoters N and NN for AADC-expressing neuronal and non-neuronal cells, respectively. Preliminary evidence suggests that leukemia inhibitory factor suppresses the activity of the neuronal promoter in cultured sympathetic neurons. Two alternative first exons, R and M, have been localized in human ChAT gene, and the corresponding promoters characterized in cholinergic PC12 and NG-108-15 cells, and in non-cholinergic neuro2A cells. Several positively or negatively acting cis elements have been localized in the two promoters, as well as a cAMP-inducible, enhancer-like element in the second intron. Among the various cell lines studied, there was no correlation between promoter activities and the expression of the endogenous ChAT gene, suggesting that the fine-tuning of ChAT gene expression is controlled by silencer elements which remain to be localized.


Asunto(s)
Descarboxilasas de Aminoácido-L-Aromático/genética , Colina O-Acetiltransferasa/genética , Regulación Enzimológica de la Expresión Génica/fisiología , Neurotransmisores/biosíntesis , Regiones Promotoras Genéticas , Animales , Secuencia de Bases , Células Cultivadas , Exones , Humanos , Datos de Secuencia Molecular , Neuronas/metabolismo , Ratas
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