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1.
Scand J Rheumatol ; 45(4): 299-303, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26854592

RESUMEN

OBJECTIVES: To evaluate the frequency of cardiovascular disease (CVD) and CVD risk factor development in adult patients previously diagnosed with juvenile idiopathic arthritis (JIA). METHOD: A cohort study was conducted utilizing patients at two academic institutions (cohorts 1 and 2). Each institution evaluated the common endpoint of CVD outcomes and CVD risk factor development in adults aged ≥ 30 years and at the 29-year follow-up from disease onset in cohorts 1 and 2, respectively, with comparison to control groups of similar age and sex. RESULTS: Cohort 1 included 41 patients with JIA and follow-up ≥ 30 years of age with comparison to 41 controls. Three patients (7%) had CVD, compared to one control (2%; p = 0.31). Cohort 2 included 170 patients with JIA and a median of 29 years of follow-up from disease onset with comparison to 91 controls. Two patients (2%) had CVD, compared to none of the controls (p = 0.29). The presence of CVD risk factors was found to be increased in the JIA group compared to the controls in three categories: family history of CVD (cohort 1), hypertension (cohort 2), and ever smokers (cohorts 2). CONCLUSIONS: There is no increase in CVD events in patients with JIA 29 years following disease onset when compared to the general population. As these cohorts age, it will be informative to evaluate whether this baseline risk remains present or a trend towards increasing CVD emerges. Continued longitudinal follow-up of these cohorts and larger population-based studies are needed to establish a definitive relationship between JIA and CVD.


Asunto(s)
Artritis Juvenil/epidemiología , Enfermedades Cardiovasculares/epidemiología , Hiperlipidemias/epidemiología , Adulto , Angina de Pecho/epidemiología , Antihipertensivos , Estudios de Casos y Controles , Estudios de Cohortes , Enfermedad de la Arteria Coronaria/epidemiología , Diabetes Mellitus/epidemiología , Femenino , Humanos , Hiperlipidemias/tratamiento farmacológico , Hipertensión/tratamiento farmacológico , Hipertensión/epidemiología , Hipolipemiantes/uso terapéutico , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Minnesota/epidemiología , Infarto del Miocardio/epidemiología , Noruega/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Fumar/epidemiología , Trombosis de la Vena/epidemiología
2.
Genes Immun ; 16(7): 470-80, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26291516

RESUMEN

Autoimmune muscle diseases (myositis) comprise a group of complex phenotypes influenced by genetic and environmental factors. To identify genetic risk factors in patients of European ancestry, we conducted a genome-wide association study (GWAS) of the major myositis phenotypes in a total of 1710 cases, which included 705 adult dermatomyositis, 473 juvenile dermatomyositis, 532 polymyositis and 202 adult dermatomyositis, juvenile dermatomyositis or polymyositis patients with anti-histidyl-tRNA synthetase (anti-Jo-1) autoantibodies, and compared them with 4724 controls. Single-nucleotide polymorphisms showing strong associations (P<5×10(-8)) in GWAS were identified in the major histocompatibility complex (MHC) region for all myositis phenotypes together, as well as for the four clinical and autoantibody phenotypes studied separately. Imputation and regression analyses found that alleles comprising the human leukocyte antigen (HLA) 8.1 ancestral haplotype (AH8.1) defined essentially all the genetic risk in the phenotypes studied. Although the HLA DRB1*03:01 allele showed slightly stronger associations with adult and juvenile dermatomyositis, and HLA B*08:01 with polymyositis and anti-Jo-1 autoantibody-positive myositis, multiple alleles of AH8.1 were required for the full risk effects. Our findings establish that alleles of the AH8.1 comprise the primary genetic risk factors associated with the major myositis phenotypes in geographically diverse Caucasian populations.


Asunto(s)
Alelos , Antígenos HLA/genética , Miositis/genética , Adolescente , Adulto , Autoanticuerpos/inmunología , Estudios de Casos y Controles , Dermatomiositis/genética , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Haplotipos , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Polimiositis/genética , Factores de Riesgo , Población Blanca
3.
J Prev Alzheimers Dis ; 11(4): 903-907, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39044501

RESUMEN

Affordable, rapid methods for identifying mild Alzheimer's disease (AD) are needed. A simple, brief performance-based test involving the learning of functional upper-extremity movements has been developed and is associated with AD pathology and functional decline. However, its specificity to AD relative to other neurodegenerative diseases that present with motor impairment is unknown. This study examined whether this novel test could distinguish between 34 participants diagnosed with mild AD (Clinical Dementia Rating Scale = 0.5-1) from 23 participants with mild-to-moderate Parkinson's disease (PD) (Hoehn and Yahr = 2-3) using Receiver Operating Characteristic analysis of secondary data from two separate clinical trials. Indicators of diagnostic accuracy demonstrated that the test identified participants with AD, who had worse scores than those with PD, suggesting it may be a viable screening tool for mild AD. Exploratory analyses with a control group (n=52) further showed that test scores were not sensitive to motor dysfunction.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Parkinson , Humanos , Enfermedad de Alzheimer/diagnóstico , Femenino , Anciano , Masculino , Enfermedad de Parkinson/diagnóstico , Sensibilidad y Especificidad , Pruebas Neuropsicológicas , Anciano de 80 o más Años , Curva ROC , Extremidad Superior/fisiopatología
4.
Arthritis Rheum ; 64(1): 285-96, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22031171

RESUMEN

OBJECTIVE: Statins reduce atherosclerosis and cardiovascular morbidity in the general population, but their efficacy and safety in children and adolescents with systemic lupus erythematosus (SLE) are unknown. This study was undertaken to determine the 3-year efficacy and safety of atorvastatin in preventing subclinical atherosclerosis progression in pediatric-onset SLE. METHODS: A total of 221 participants with pediatric SLE (ages 10-21 years) from 21 North American sites were enrolled in the Atherosclerosis Prevention in Pediatric Lupus Erythematosus study, a randomized double-blind, placebo-controlled clinical trial, between August 2003 and November 2006 with 36-month followup. Participants were randomized to receive atorvastatin (n=113) or placebo (n=108) at 10 or 20 mg/day depending on weight, in addition to usual care. The primary end point was progression of mean-mean common carotid intima-media thickening (CIMT) measured by ultrasound. Secondary end points included other segment/wall-specific CIMT measures, lipid profile, high-sensitivity C-reactive protein (hsCRP) level, and SLE disease activity and damage outcomes. RESULTS: Progression of mean-mean common CIMT did not differ significantly between treatment groups (0.0010 mm/year for atorvastatin versus 0.0024 mm/year for placebo; P=0.24). The atorvastatin group achieved lower hsCRP (P=0.04), total cholesterol (P<0.001), and low-density lipoprotein (P<0.001) levels compared with placebo. In the placebo group, CIMT progressed significantly across all CIMT outcomes (0.0023-0.0144 mm/year; P<0.05). Serious adverse events and critical safety measures did not differ between groups. CONCLUSION: Our results indicate that routine statin use over 3 years has no significant effect on subclinical atherosclerosis progression in young SLE patients; however, further analyses may suggest subgroups that would benefit from targeted statin therapy. Atorvastatin was well tolerated without safety concerns.


Asunto(s)
Anticolesterolemiantes/uso terapéutico , Aterosclerosis/prevención & control , Ácidos Heptanoicos/uso terapéutico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Pirroles/uso terapéutico , Adolescente , Aterosclerosis/complicaciones , Aterosclerosis/diagnóstico , Atorvastatina , Grosor Intima-Media Carotídeo , Niño , Progresión de la Enfermedad , Método Doble Ciego , Femenino , Humanos , Lípidos/sangre , Lupus Eritematoso Sistémico/sangre , Lupus Eritematoso Sistémico/complicaciones , Masculino , Resultado del Tratamiento , Adulto Joven
5.
Lupus ; 19(11): 1315-25, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20861207

RESUMEN

As part of the Atherosclerosis Prevention in Pediatric Lupus Erythematosus (APPLE) Trial, a prospective multicenter cohort of 221 children and adolescents with systemic lupus erythematosus (SLE) (mean age 15.7 years, 83% female) underwent baseline measurement of markers of cardiovascular risk, including fasting levels of high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides (TG), lipoprotein A (Lpa), homocysteine and high-sensitivity C-reactive protein (hs-CRP). A cross-sectional analysis of the baseline laboratory values and clinical characteristics of this cohort was performed. Univariable relationships between the cardiovascular markers of interest and clinical variables were assessed, followed by multivariable linear regression modeling. Mean levels of LDL, HDL, Lpa, TG, hs-CRP and homocysteine were in the normal or borderline ranges. In multivariable analysis, increased Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), prednisone dose, and hypertension (HTN) were independently associated with higher LDL levels. Higher hs-CRP and creatinine clearance were independently related to lower HDL levels. Higher body mass index (BMI), prednisone dose, and homocysteine levels were independently associated with higher TG levels. Only Hispanic or non-White status predicted higher Lpa levels. Proteinuria, higher TG and lower creatinine clearance were independently associated with higher homocysteine levels, while use of multivitamin with folate predicted lower homocysteine levels. Higher BMI, lower HDL, and longer SLE disease duration, but not SLEDAI, were independently associated with higher hs-CRP levels. The R(2) for these models ranged from 7% to 23%. SLE disease activity as measured by the SLEDAI was associated only with higher LDL levels and not with hs-CRP. Markers of renal injury (HTN, proteinuria, and creatinine clearance) were independently associated with levels of LDL, HDL, and homocysteine, highlighting the importance of renal status in the cardiovascular health of children and adolescents with SLE. Future longitudinal analysis of the APPLE cohort is needed to further examine these relationships.


Asunto(s)
Biomarcadores/sangre , Enfermedades Cardiovasculares , Lupus Eritematoso Sistémico , Adolescente , Proteína C-Reactiva/metabolismo , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/etiología , Niño , Colesterol/sangre , Estudios Transversales , Método Doble Ciego , Femenino , Humanos , Lipoproteína(a)/sangre , Lipoproteínas HDL/sangre , Lipoproteínas LDL/sangre , Lupus Eritematoso Sistémico/sangre , Lupus Eritematoso Sistémico/complicaciones , Placebos , Factores de Riesgo , Triglicéridos/sangre , Adulto Joven
6.
Hum Immunol ; 60(3): 255-8, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10321963

RESUMEN

Annually approximately 1:200,000 young children and adolescents are affected by juvenile dermatomyositis (JDM). Genetic factors are thought to contribute to the etiology. Since the discovery of the human leukocyte antigen class II associated DM molecule much has been learned about its role in the normal processing of HLA-class II molecules with a limited number of polymorphisms being found. Blood samples were collected from 30 patients who were seen in the clinic and 40 healthy volunteers. Exon 3 of the HLA-DM A and B genes were amplified and specific polymorphisms were identified given allele designations. The DMA*0103 allele was found in 43% of patient alleles versus 8% in the control group, this difference reached significance at a p value of 0.0004. The DMB*0102 allele was found in 20% of patients compared with 3% of the controls with a calculated p value of 0.037. Relative risk (RR) ratios with CI were as follows: DMA*0103 vs control RR = 5.7 and DMB*0102 vs control RR = 8. In conclusion, we feel that the polymorphisms represented in the DMA*0103 and the DMB*0102 alleles are increased in frequency in our JDM patients.


Asunto(s)
Dermatomiositis/inmunología , Antígenos HLA-D/genética , Antígenos de Histocompatibilidad Clase II , Polimorfismo Genético , Niño , Cartilla de ADN , Dermatomiositis/genética , Exones , Frecuencia de los Genes , Haplotipos , Prueba de Histocompatibilidad , Humanos , Sondas de Oligonucleótidos
7.
Hum Immunol ; 44(3): 131-5, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8666549

RESUMEN

We wanted to determine if HLA-DQA1*0501 is as strongly associated with JDMS in Hispanic and African Americans as it is Caucasians. Using DNA sequencing and oligonucleotide typing, the DNA of 70 JDMS subjects was studied. The HLA-DQA1 allelle DQA1*0501 was present in 13 out of 15 (87%) of the African-American JDMS subjects vs 9 out of 27 (33%) of the African-American controls (p < 0.0009), 12 out of 13 (92%) of the Hispanic JDMS subjects vs 5 out of 18 (28%) of the Hispanic controls (p < 0.0004), and 36 out of 42 (86%) of the Caucasian JDMS subjects vs 36 out of 78 (46%) of the Caucasian controls (p < 0.0009).


Asunto(s)
Alelos , Dermatomiositis/genética , Dermatomiositis/inmunología , Genes MHC Clase II/inmunología , Antígenos HLA-DQ/genética , Población Negra/genética , Niño , Preescolar , Dermatomiositis/epidemiología , Cadenas alfa de HLA-DQ , Cadenas beta de HLA-DQ , Hispánicos o Latinos/genética , Humanos , Población Blanca/genética
8.
Hum Immunol ; 32(4): 235-40, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1783570

RESUMEN

Juvenile dermatomyositis (JDMS) is an inflammatory disease associated with HLA-DR3. We therefore undertook molecular genetic studies of HLA region genes to determine whether HLA-DR3 itself confers susceptibility to JDMS or whether susceptibility is conferred by alleles in linkage disequilibrium with HLA-DR3. Our results indicate that JDMS is associated with the HLA-DQA1 allele DQA1 *0501 on non-DR3 haplotypes in Caucasian JDMS. Furthermore, the reported of association between the C4A gene deletion and JDMS is likely due to linkage disequilibrium with HLA-DR3.


Asunto(s)
Dermatomiositis/genética , Genes MHC Clase II/genética , Antígenos HLA-DQ/genética , Adolescente , Alelos , Niño , Preescolar , ADN/análisis , Susceptibilidad a Enfermedades , Electroforesis en Gel de Agar , Femenino , Cadenas alfa de HLA-DQ , Antígeno HLA-DR3/genética , Humanos , Lactante , Desequilibrio de Ligamiento , Masculino , Biología Molecular , Reacción en Cadena de la Polimerasa , Factores de Riesgo
9.
Hum Immunol ; 45(1): 59-63, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8655362

RESUMEN

SLE is dramatically more prevalent in persons of African descent than in other populations. Several genes in the class III region of the MHC have been considered as potential susceptibility loci for this disorder, but the primary association(s) remains unknown. The stress protein gene, hsp70-2, is of special interest in this regard because it encodes a protein functionally relevant to antigen processing and presentation and has itself been identified as a putative susceptibility locus in organ-specific autoimmune diseases in Caucasians. To clarify the relationship of the hsp70-2 gene to SLE in African Americans, genomic DNA from 46 patients and 42 appropriately matched control subjects was analyzed for an RFLP of the hsp70-2 gene using the probe pH2.3 and the restriction endonuclease PstI, which identifies alleles of 8.5 and 9.0 kb. The 8.5-kb hsp70-2 allele was associated with SLE in this population (X2 = 8.2473, p = 0.0044). This association was not due to linkage disequilibrium with the C4A deletion or with HLA-DR3, as has been reported in Caucasians with IDDM. These data suggest that the 8.5-kb hsp70-2 allele may be an independent susceptibility marker for SLE in African Americans.


Asunto(s)
Alelos , Población Negra/genética , Proteínas HSP70 de Choque Térmico/genética , Lupus Eritematoso Sistémico/genética , Polimorfismo de Longitud del Fragmento de Restricción , Secuencia de Bases , Desoxirribonucleasas de Localización Especificada Tipo II , Susceptibilidad a Enfermedades , Marcadores Genéticos , Humanos , Lupus Eritematoso Sistémico/etiología , Datos de Secuencia Molecular , Factores de Riesgo
10.
J Biomater Appl ; 6(3): 198-215, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1573553

RESUMEN

While occlusive wound dressings help provide patients with moist wound healing to reduce pain and increase reepithelialization rate, the moisture vapor transmission rate (MVTR) of these dressings remains constant even though wound exudate levels may vary with time and from wound to wound. The clinician is therefore faced with exudate buildup in heavily exuding wounds and desiccation in lightly exuding wounds-a situation requiring frequent patient monitoring and dressing changes. Am "intelligent" wound dressing would have the ability to automatically respond to a wound's exudate level by self-adjusting its MVTR to maintain a constant moist wound environment. Such a dressing could help ensure that exudate buildup or wound desiccation is reduced or avoided. Three commercial wound dressings (hydrocolloid, thin film, and membrane laminate) were studied for their ability to alter their MVTR in response to varying moisture level. An efficient test methodology and experimental design was developed, which involved direct and indirect fluid contact with the dressings using two temperatures and two test methods. One dressing, a membrane laminate, was found to exhibit intelligent MVTR behavior. Data is presented which shows this dressing's ability to adjust its MVTR nearly eight-fold as a function of hydration level. Information regarding the mechanism of action of this intelligent dressing is also presented.


Asunto(s)
Materiales Biocompatibles/uso terapéutico , Apósitos Oclusivos , Materiales Biocompatibles/química , Humanos , Ensayo de Materiales/métodos , Probabilidad , Proyectos de Investigación , Temperatura , Volatilización
11.
J Biomater Appl ; 6(2): 110-30, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1779410

RESUMEN

At present all the commercially available "medical grade" urethane elastomers exhibit a phenomenon known as environmental stress cracking (ESC). This phenomenon is characterized by surface microcracking when the elastomer is elongated while in vivo. The degree of strain that is required to initiate microcracking varies from composition to composition. It has been found that harder compounds generally tend to have a higher strain threshold than corresponding softer ones. We theorized that this degradation occurs when certain enzymes (present only in vivo) attack and break down the ether linkages that link the polymer molecules together. Those elastomers that contain more ether linkages (such as the softer compositions) appear to microcrack more easily than elastomers with fewer ether linkages (such as the harder ones). The molecular composition of ChronoFlex urethane has been chosen so that the finished elastomer will be free of ether linkages; thus, it is expected to be immune from environmental stress cracking.


Asunto(s)
Materiales Biocompatibles , Poliuretanos , Animales , Fenómenos Biomecánicos , Femenino , Prótesis e Implantes , Conejos , Goma
12.
Med Device Technol ; 3(10): 42-51, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10171586

RESUMEN

The generic term polyurethane represents the most versatile family of synthetic polymers. The unsurpassed physical and chemical properties of polyurethanes, coupled with their biocompatibility, have led to their use in a wide range of biomedical applications. Although polyurethanes have been shown to be stable in vitro for many years, they can undergo rapid microcracking when implanted. These microcracks not only weaken the polymer but also serve as nucleation sites for thrombus formation and lead to catastrophic failure. In this article, the authors report on the development and testing of a new ether-free polyurethane that does not exhibit surface microcracking under accelerated in vivo condition.


Asunto(s)
Poliuretanos/química , Prótesis e Implantes , Animales , Biodegradación Ambiental , Femenino , Humanos , Ensayo de Materiales , Poliuretanos/efectos adversos , Prótesis e Implantes/efectos adversos , Conejos , Goma , Estrés Mecánico , Resistencia a la Tracción
18.
Compr Ther ; 15(1): 31-6, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2650970
19.
Rheumatology (Oxford) ; 46(3): 398-402, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17085771

RESUMEN

OBJECTIVE: Localized scleroderma causes thickening of the skin due to excessive collagen deposition. This condition has clinical and histopathological similarities to chronic graft-vs-host disease. We wanted to identify whether chimeric cells are present in the affected tissue in localized scleroderma and to further investigate the role of chimerism by immunophenotyping the chimeric cells. We hypothesize that the presence of chimerism and immunotypic chimeric cells will lend to an understanding of the pathogenesis of localized scleroderma and possible mechanisms by which chimeric cells participate in autoimmunity. METHODS: We studied skin biopsies from 18 localized scleroderma patients and compared them with concurrent biopsies from unaffected skin in a subset of patients. Skin biopsies from morphoea and linear scleroderma patients were analysed for the presence of chimeric cells using male-female (X, Y) differences. Cell surface markers (CD4, CD8, CD19/20, CD68, S100, CD14 and CD56) were determined for cell phenotyping of chimeric cells. RESULTS: Overall, the affected tissue contained a greater number of lymphocytic inflammatory cells. In the affected tissue, 38% of the total chimeric cells were CD68+ (dendritic cell, monocyte and macrophage marker), 29% Langerin/S100+ (dendritic cell marker), 26% CD8+ (cytotoxic T-lymphocyte marker), 20% CD19/20+ (B-lymphocyte marker), 14% CD4+ (T-helper lymphocyte) and 0% CD56+ (natural killer cell marker). CONCLUSIONS: We report that not only are chimeric cells present in affected localized scleroderma lesions but they also are more likely to be dendritic cells and B lymphocytes suggesting a role in the pathogenesis of localized scleroderma.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Quimera/inmunología , Esclerodermia Localizada/inmunología , Adolescente , Adulto , Anciano , Linfocitos B/inmunología , Niño , Células Dendríticas/inmunología , Femenino , Humanos , Inmunofenotipificación , Masculino , Persona de Mediana Edad , Piel/inmunología
20.
Rheumatology (Oxford) ; 46(10): 1606-11, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17890275

RESUMEN

OBJECTIVES: Clinical care and therapeutic trials in idiopathic inflammatory myopathies (IIM) require accurate and consistent assessment of cutaneous involvement. The Cutaneous Assessment Tool (CAT) was designed to measure skin activity and damage in IIM. We describe the development and inter-rater reliability of the CAT, and the frequency of lesions endorsed in a large population of juvenile IIM patients. METHODS: The CAT includes 10 activity, 4 damage and 7 combined lesions. Thirty-two photographic slides depicting IIM skin lesions were assessed by 11 raters. One hundred and twenty-three children were assessed by 11 paediatric rheumatologists at 10 centres. Inter-rater reliability was assessed using simple agreements and intra-class correlation coefficients (ICC). RESULTS: Simple agreements in recognizing lesions as present or absent were generally high (0.5-1.0). ICCs for CAT lesions were moderate (0.4-0.75) in both slides and real patients. ICCs for the CAT activity and damage scores were 0.71 and 0.81, respectively. CAT activity scores ranged from 0 to 44 (median 7, potential range 0-96) and CAT damage scores ranged from 0 to 13 (median 1, potential range 0-22). The most common cutaneous lesions endorsed were periungual capillary loop changes (63%), Gottron's papules/sign (53%), heliotrope rash (49%) and malar/facial erythema (49%). CONCLUSIONS: Total CAT activity and damage scores have moderate to good reliability. Assessors generally agree on the presence of a variety of cutaneous lesions. The CAT is a promising, semi-quantitative tool to comprehensively assess skin disease activity and damage in IIM.


Asunto(s)
Dermatomiositis/diagnóstico , Índice de Severidad de la Enfermedad , Niño , Humanos , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados
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