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1.
Am J Vet Res ; 82(2): 152-157, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33480279

RESUMO

OBJECTIVE: To evaluate surfactant protein D (SP-D) concentrations in serum and bronchoalveolar lavage fluid (BALF) from young healthy horses on pasture or housed in a typical barn. ANIMALS: 20 young healthy horses. PROCEDURES: Horses were randomly assigned to 1 of 2 groups (pasture, n = 10; barn, 10), and serum and BALF samples were collected for SP-D determination at baseline (all horses on pasture) and 2 weeks and 4 weeks after the barn group of horses was relocated from the pasture to the barn. Other evaluations included physical and tracheoscopic examinations. Findings were compared within and between groups. RESULTS: Physical and tracheoscopic examinations, CBC, and serum biochemical analysis did not reveal evidence of respiratory disease, and no significant differences were present within and between groups. Serum SP-D concentrations did not significantly differ within and between groups, but BALF SP-D concentrations were significantly lower for the barn group at 2 weeks but not at 4 weeks, compared with baseline. The BALF SP-D concentration-to-BALF total protein concentration ratio was < 1.5 and did not significantly differ within and between groups. CONCLUSIONS AND CLINICAL RELEVANCE: A mild decrease was evident in the concentration of SP-D in the BALF collected from young healthy horses after 2 weeks of exposure to a barn environment. The clinical importance of this finding remains to be determined.


Assuntos
Doenças dos Cavalos , Doenças Respiratórias , Animais , Lavagem Broncoalveolar/veterinária , Líquido da Lavagem Broncoalveolar , Cavalos , Proteína D Associada a Surfactante Pulmonar , Doenças Respiratórias/veterinária
2.
J Am Assoc Nurse Pract ; 33(6): 451-458, 2020 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-32541576

RESUMO

BACKGROUND: Transgender people face a multitude of health care access barriers that create wide disparities in health. Transgender people have more untreated acute and chronic conditions than the cisgender population. PURPOSE: The purpose of this study was to describe positive and negative experiences of transgender people when accessing health care. METHODOLOGICAL ORIENTATION: Qualitative methods including semi-structured interviews and content analysis for identification of themes. SAMPLE: Nine transgender people ranging in age from 20 to 35 years who currently reside in a metropolitan area of the Southwestern United States. CONCLUSIONS: The interviews contained candid stories about the participants' health care experiences and included perspectives about provider knowledge, provider communication, and provider office interactions. Findings identified health care disparities among transgender people related, in part, to negative experiences in the health care environment. Some of these negative experiences arose from the uncertainty of providers' transgender-specific health care knowledge and anxiety about dysphoria-triggering communication in the health care environment. IMPLICATIONS FOR PRACTICE: These findings enhance practice by offering insight into how health care providers and personnel interactions influence the experience of transgender patients and help health care providers and personnel understand situations that create anxiety and dysphoria in transgender patients.


Assuntos
Pessoas Transgênero , Adulto , Pessoal de Saúde , Acessibilidade aos Serviços de Saúde , Disparidades em Assistência à Saúde , Humanos , Pesquisa Qualitativa , Adulto Jovem
3.
Obstet Med ; 11(1): 32-34, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29636812

RESUMO

BACKGROUND: There is recent interest exploring the possible impact of sleep disordered breathing on the mechanisms of preeclampsia. A biomarker of preeclampsia, soluble fms-like tyrosine kinase-1, has come to prominence in recent years. The aim of this study was to investigate the relationship between continuous positive airway pressure treatment, sleep disordered breathing and soluble fms-like tyrosine kinase-1 concentrations during pregnancy. METHODS: A 38-year-old G1P0 presented at 20 + 5 weeks. She had a history of chronic hypertension. Sleep studies revealed she had sleep disordered breathing with an AHI of 7.3/h. She was commenced on continuous positive airway pressure. Soluble fms-like tyrosine kinase-1 concentrations and blood pressure recordings were taken at various points during her pregnancy. RESULTS: She did not develop preeclampsia or require an escalation in her antihypertensives. Soluble fms-like tyrosine kinase-1 concentrations rose 16% from a low baseline. She remained compliant with her continuous positive airway pressure. She progressed to birth a well, live, term baby. CONCLUSION: Continuous positive airway pressure treatment controlled sleep disordered breathing in a high risk pregnant woman with chronic hypertension with no increase in soluble fms-like tyrosine kinase-1 concentrations.

4.
Intern Med J ; 48(3): 269-275, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29083111

RESUMO

BACKGROUND: The prevalence of hypertensive disorders of pregnancy (HDP) in Australia's urban indigenous women is unknown. AIM: To explore the risk factors associated with HDP for a cohort of urban indigenous women in South-Western Sydney, Australia. METHODS: This study was conducted in partnership with the Tharawal Aboriginal Medical Service. Women (18-45 years) were recruited at the clinic and community events. The quantitative questionnaire included obstetric history, personal and family history of hypertension. Anthropometric measurements and blood pressure were conducted. Rates were compared with Australian Bureau of Statistics (ABS) national rates. RESULTS: Eighty-three participants completed the questionnaire. The rate of ever having HDP in a pregnancy was 36.1%. The overall ABS rate was 9.8% and for indigenous women, 14%. The mean maternal age at first pregnancy was 20.8 years (SD 3.7 years). The mean body mass index (BMI) of the sample population (n = 81) was 32.2 kg/m2 (SD 9.5 kg/m2 ) and BMI was not related to HDP (P = 0.197). Of those questioned, 25.3% had an individual history and 63.9% had a family history of hypertension. The effect of family history of hypertension (P = 0.020) (odds ratio (OR) 4.29; 95% confidence interval (CI); 1.42-12.93) and individual history of hypertension (P < 0.001) (OR 15.69; 95% CI; 4.50-54.76) were associated with HDP. CONCLUSION: There was a higher rate of HDP in urban indigenous women compared to the national indigenous prevalence. The family history, or individual history of hypertension was the most significant risk factors and BMI was not identified as a risk factor for HDP in this population.


Assuntos
Índice de Massa Corporal , Hipertensão Induzida pela Gravidez/diagnóstico , Hipertensão Induzida pela Gravidez/etnologia , Havaiano Nativo ou Outro Ilhéu do Pacífico/etnologia , Fumar/etnologia , População Urbana , Adolescente , Adulto , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/etnologia , Pessoa de Meia-Idade , New South Wales/etnologia , Gravidez , Fatores de Risco , Fumar/efeitos adversos , Inquéritos e Questionários , População Urbana/tendências , Adulto Jovem
5.
Front Cardiovasc Med ; 3: 20, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27446933

RESUMO

Advances in DNA sequencing have made large, diagnostic gene panels affordable and efficient. Broad adoption of such panels has begun to deliver on the promises of personalized medicine, but has also brought new challenges such as the presence of unexpected results, or results of uncertain clinical significance. Genetic analysis of inherited cardiac conditions is particularly challenging due to the extensive genetic heterogeneity underlying cardiac phenotypes, and the overlapping, variable, and incompletely penetrant nature of their clinical presentations. The design of effective diagnostic tests and the effective use of the results depend on a clear understanding of the relationship between each gene and each considered condition. To address these issues, we developed simple, systematic approaches to three fundamental challenges: (1) evaluating the strength of the evidence suggesting that a particular condition is caused by pathogenic variants in a particular gene, (2) evaluating whether unusual genotype/phenotype observations represent a plausible expansion of clinical phenotype associated with a gene, and (3) establishing a molecular diagnostic strategy to capture overlapping clinical presentations. These approaches focus on the systematic evaluation of the pathogenicity of variants identified in clinically affected individuals, and the natural history of disease in those individuals. Here, we applied these approaches to the evaluation of more than 100 genes reported to be associated with inherited cardiomyopathies and arrhythmias including hypertrophic cardiomyopathy, dilated cardiomyopathy, arrhythmogenic right ventricular dysplasia or cardiomyopathy, long QT syndrome, short QT syndrome, Brugada, and catecholaminergic polymorphic ventricular tachycardia, and to a set of related syndromes such as Noonan Syndrome and Fabry disease. These approaches provide a framework for delivering meaningful and accurate genetic test results to individuals with hereditary cardiac conditions.

6.
Genet Test Mol Biomarkers ; 17(7): 553-61, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23631430

RESUMO

AIM: Our aim was to examine the diagnostic yield of genetic testing in 855 consecutive unrelated cases referred for Long QT syndrome (LQTS). RESULTS: Eight hundred fifty five consecutive patients with a mean age at testing of 27.5±18.6 years, were referred for LQTS genetic testing and had accompanying clinical information. KCNQ1, KCNH2, SCN5A, ANK2, KCNE1, KCNE2, CACNA1C, KCNJ2, CAV3, and SCN4B were analyzed using Next-Generation sequencing in all patients, and 395 patients were also tested for an additional two genes, AKAP9 and SNTA1. We retrospectively analyzed the diagnostic yield of this genetic test and factors that predicted the likelihood of a disease causing mutation using ANOVA, χ2, t-test, and receiver operator curves. At least one mutation was identified in 30.3% of the patients (n=259), and 18 patients (2.1%) had two mutations. Patients with two mutations had a longer QTc interval (p<0.01) than patients with one mutation. A longer QTc duration and family history of LQTS were each associated with a higher yield of positive results on genetic testing (p<0.01 for each). Using a QTc cutoff of 476 msec or greater, the genetic testing had a sensitivity of 72% and a specificity of 49%. Mutations within the transmembrane domain of KCNQ1 were associated with a greater risk of cardiac arrest and syncope relative to mutations in other domains of the gene. Mutations in SCN5A were associated with a higher frequency of cardiac arrest (52.6%). CONCLUSION: Sequencing-based genetic testing has a sensitivity of 72% and has clinical utility.


Assuntos
Testes Genéticos/métodos , Síndrome do QT Longo/diagnóstico , Síndrome do QT Longo/genética , Mutação , Adolescente , Adulto , Criança , Feminino , Predisposição Genética para Doença , Parada Cardíaca/genética , Humanos , Canal de Potássio KCNQ1/genética , Síndrome do QT Longo/fisiopatologia , Masculino , Pessoa de Meia-Idade , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Sensibilidade e Especificidade , Síncope/genética , Adulto Jovem
7.
Circ Cardiovasc Genet ; 5(1): 18-24, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22238189

RESUMO

BACKGROUND: Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is characterized by frequent life-threatening ventricular arrhythmias, diagnosed on average in the teens to mid-50s and commonly treated by implantable cardioverter defibrillators (ICDs). As younger age and high frequency of ICD discharges are risk factors for difficulties in psychosocial adjustment, we developed a study to assess psychosocial adjustment among patients with ARVD/C and to determine risk factors for poor adjustment in this high-risk population. METHODS AND RESULTS: Eighty-six adults enrolled in the Johns Hopkins ARVD Registry (38 male; mean age, 45.4±12.9 years), with an ICD in place for a median 3.2 years (range, 0.2 to 20.1 years), completed a set of questionnaires measuring ICD-specific anxiety (Florida Shock Anxiety Scale), device acceptance (Florida Patient Acceptance Survey), anxiety and depression (Hospital Anxiety and Depression Scale), and functional capacity (Duke Activity Status Index). Although overall device acceptance (Florida Patient Acceptance Survey mean, 76.7±15.3) was normative, patients with ARVD/C had substantially elevated body image concerns (Florida Patient Acceptance Survey subscale mean, 17.9±23.5) and device-related distress (subscale mean, 26.5±19.2), particularly among younger patients (P<0.01). Patients with ARVD/C had elevated ICD-specific (Florida Shock Anxiety Scale mean, 22.9±7.8) and general clinical anxiety (Hospital Anxiety and Depression Scale anxiety subscale mean, 6.2±3.9). Device-specific anxiety (Florida Shock Anxiety Scale) was predicted by younger age (P<0.0001), poorer functional capacity (P=0.016), having an ICD shock (P=0.003), and shorter time since ICD implant (P=0.007). Participants with poor device adjustment had an increased likelihood of clinically significant anxiety (P=0.006) and depression (P=0.008). CONCLUSIONS: Patients with ARVD/C are at elevated risk for anxiety, and young patients face challenges with device acceptance. Risk factors for poor device adjustment may be used clinically to identify patients at high-risk of psychological distress.


Assuntos
Adaptação Psicológica , Displasia Arritmogênica Ventricular Direita/psicologia , Desfibriladores Implantáveis , Adolescente , Adulto , Idoso , Ansiedade , Displasia Arritmogênica Ventricular Direita/diagnóstico , Displasia Arritmogênica Ventricular Direita/terapia , Estudos de Coortes , Demografia , Depressão , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
8.
J Cardiovasc Electrophysiol ; 22(5): 561-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21114702

RESUMO

INTRODUCTION: Despite the use of standardized definitions, widely varying prevalence estimates of electrocardiographic (ECG) features related to arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) have been reported in different cohorts. This study was aimed at examining the variability in the ECG interpretation resulting from the same reader, different readers, and using different ECG-resolutions. METHODS AND RESULTS: Blinded to other clinical data, 2 readers examined quantitative and qualitative ECG features of 20 (10 ARVD/C) randomly selected individuals. ECGs were recorded at standard-speed (SS) and double-speed-double-amplitude (DS) settings. The SS ECGs were scanned, magnified 4×, and evaluated using electronic calipers (EL). One reader repeated all measurements. For both readers, the intraclass correlation coefficient (ICC) for the measurement of QRS duration was good between conventional and electronic evaluation [DS vs EL: Reader 1--0.64 (0.52-0.73); Reader 2--0.67 (0.55-0.76)][SS vs EL: Reader 1--0.60 (0.47-0.70); Reader 2--0.60 (0.47-0.70)]. Using the same resolution, the intrareader ICC was good for SS [0.70 (0.59-0.78)], DS [0.85 (0.80-0.90)], and EL [0.70 (0.69-0.83)] resolutions, but deteriorated for interreader comparisons [0.50 (0.36-0.62), 0.75 (0.66-0.82), and 0.75 (0.66-0.82), respectively]. For qualitative parameters, the intra- and interreader agreement was inconsistent for all but 2 parameters. Both readers were in perfect agreement while interpreting right precordial T-wave inversion [κ= 1] and right bundle branch block morphology (RBBB) [κ= 0.83 (0.5-1.0)] even when using SS resolution. CONCLUSIONS: Right precordial t-wave inversion and RBBB are the only ECG parameters that can be detected consistently even using the conventionally used ECG-resolution. The substantial variability in evaluation of other parameters is not improved even with the use of higher resolutions.


Assuntos
Displasia Arritmogênica Ventricular Direita/diagnóstico , Artefatos , Eletrocardiografia/instrumentação , Eletrocardiografia/métodos , Adulto , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
J Cardiovasc Transl Res ; 3(6): 663-73, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20857253

RESUMO

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is an inherited form of cardiomyopathy with low penetrance and variable expressivity. Dominant mutations and rare polymorphisms in desmosome genes are frequently identified. We reasoned that individuals with earlier onset disease would have more frequent desmosome gene mutations and rare polymorphisms. Three groups were compared: Young with symptoms attributable to ARVD/C or a diagnosis of ARVD/C at age of 21 years or earlier, Middle with first symptoms or diagnosis age of 22-49 years, and Late with first symptoms or diagnosis at age of 50 or more years. deoxyribonucleic acid (DNA) sequence analysis was performed on five cardiac desmosome genes, and the presence of mutations and rare missense polymorphisms was compared among the three groups. In the entire Young cohort, 20 (67%) had one or more cardiac desmosome gene mutations. The prevalence of cardiac desmosome gene mutations was similar in the Middle (48%) and Late (53%) cohorts (P = 0.23). Similar numbers of individuals in each cohort had more than one desmosome gene mutation, although the numbers are too small for statistical comparisons. The prevalence of certain rare missense DNA variants was not different among the cohorts (P = 0.71), yet these rare missense alleles were more prevalent in the overall study cohort of 112 ARVD/C participants compared to 100 race-matched controls (P = 0.027). The presence of these variants did not associate with the age of onset of ARVD/C or ventricular tachycardia. These findings highlight the complex interplay of environmental and genetic factors contributing to this condition.


Assuntos
Displasia Arritmogênica Ventricular Direita/genética , Desmossomos/genética , Mutação , Polimorfismo Genético , Adolescente , Adulto , Idade de Início , Idoso , Displasia Arritmogênica Ventricular Direita/epidemiologia , Displasia Arritmogênica Ventricular Direita/fisiopatologia , Baltimore , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Fenótipo , Sistema de Registros , Medição de Risco , Fatores de Risco , Adulto Jovem
10.
Circ Cardiovasc Genet ; 2(5): 428-35, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20031617

RESUMO

BACKGROUND: Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is an inherited disorder typically caused by mutations in components of the cardiac desmosome. The prevalence and significance of desmosome mutations among patients with ARVD/C in North America have not been described previously. We report comprehensive desmosome genetic analysis for 100 North Americans with clinically confirmed or suspected ARVD/C. METHODS AND RESULTS: In 82 individuals with ARVD/C and 18 people with suspected ARVD/C, DNA sequence analysis was performed on PKP2, DSG2, DSP, DSC2, and JUP. In those with ARVD/C, 52% harbored a desmosome mutation. A majority of these mutations occurred in PKP2. Notably, 3 of the individuals studied have a mutation in more than 1 gene. Patients with a desmosome mutation were more likely to have experienced ventricular tachycardia (73% versus 44%), and they presented at a younger age (33 versus 41 years) compared with those without a desmosome mutation. Men with ARVD/C were more likely than women to carry a desmosome mutation (63% versus 38%). A mutation was identified in 5 of 18 patients (28%) with suspected ARVD. In this smaller subgroup, there were no significant phenotypic differences identified between individuals with a desmosome mutation compared with those without a mutation. CONCLUSIONS: Our study shows that in 52% of North Americans with ARVD/C a mutation in one of the cardiac desmosome genes can be identified. Compared with those without a desmosome gene mutation, individuals with a desmosome gene mutation had earlier-onset ARVD/C and were more likely to have ventricular tachycardia.


Assuntos
Displasia Arritmogênica Ventricular Direita/genética , Desmossomos/genética , Mutação , Adolescente , Adulto , Idoso , Sequência de Aminoácidos , Criança , Pré-Escolar , Estudos de Coortes , Desmocolinas/química , Desmocolinas/genética , Desmogleína 2/química , Desmogleína 2/genética , Desmoplaquinas/química , Desmoplaquinas/genética , Desmossomos/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , América do Norte , Linhagem , Placofilinas/química , Placofilinas/genética , Alinhamento de Sequência , Adulto Jovem , gama Catenina
11.
J Am Coll Cardiol ; 54(5): 445-51, 2009 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-19628120

RESUMO

OBJECTIVES: This study sought to investigate the prevalence and mechanisms underlying right ventricular (RV) dyssynchrony in arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) using tissue Doppler echocardiography (TDE). BACKGROUND: An ARVD/C is characterized by fibrofatty replacement of RV myocardium and RV dilation. These pathologic changes may result in electromechanical dyssynchrony. METHODS: Echocardiography, both conventional and TDE, was performed in 52 ARVD/C patients fulfilling Task Force criteria and 25 control subjects. The RV end-diastolic and -systolic areas, right ventricular fractional area change (RVFAC), and left ventricular (LV) volumes and function were assessed. Mechanical synchrony was assessed by measuring differences in time-to-peak systolic velocity (T(SV)) between the RV free wall, ventricular septum, and LV lateral wall. An RV dyssynchrony was defined as the difference in T(SV) between the RV free wall and the ventricular septum, >2 SD above the mean value for control subjects. RESULTS: The mean difference in RV T(SV) was higher in ARVD/C compared with control subjects (55 +/- 34 ms vs. 26 +/- 15 ms, p < 0.001). Significant RV dyssynchrony was not noted in any of the control subjects. Based on a cutoff value of 56 ms, significant RV dyssynchrony was present in 26 ARVD/C patients (50%). Patients with RV dyssynchrony had a larger RV end-diastolic area (22 +/- 5 cm(2) vs. 19 +/- 4 cm(2), p = 0.02), and lower RVFAC (29 +/- 8% vs. 34 +/- 8%, p = 0.03) compared with ARVD/C patients without RV dyssynchrony. No differences in QRS duration, LV volumes, or function were present between the 2 groups. CONCLUSIONS: An RV dyssynchrony may occur in up to 50% of ARVD/C patients, and is associated with RV remodeling. This finding may have therapeutic and prognostic implications in ARVD/C.


Assuntos
Displasia Arritmogênica Ventricular Direita/epidemiologia , Displasia Arritmogênica Ventricular Direita/fisiopatologia , Disfunção Ventricular Direita/patologia , Disfunção Ventricular Direita/fisiopatologia , Adulto , Displasia Arritmogênica Ventricular Direita/patologia , Ecocardiografia Doppler , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Remodelação Ventricular
12.
Circulation ; 120(6): 477-87, 2009 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-19635971

RESUMO

BACKGROUND: The purpose of this study was to reevaluate the ECG features of arrhythmogenic right ventricular dysplasia (ARVD). The second objective was to evaluate the sensitivity and specificity of the standard and newly proposed diagnostic ECG markers in the presence of a right bundle-branch block (RBBB). METHODS AND RESULTS: One hundred patients with ARVD (57 men; aged 39+/-15 years) and 57 controls (21 men; aged 40+/-17 years) were included. Among the 100 patients with ARVD, a complete RBBB was present in 17 patients, and 15 patients had an incomplete RBBB. T-wave inversion through V(3) demonstrated optimal sensitivity and specificity in both ARVD patients without a complete RBBB or incomplete RBBB (71% [95% confidence interval, 58% to 81%] and 96% [95% confidence interval, 81% to 100%], respectively) and in ARVD patients with incomplete RBBB (73% [95% confidence interval, 45% to 92%] and 95% [95% confidence interval, 77% to 100%], respectively). Between ARVD patients and controls with a complete RBBB, the only 2 parameters that differed were the prevalence of T-wave inversion through V(4) (59% versus 12%, respectively; P<0.05) and an r'/s ratio in V(1) <1 (88% versus 14%, respectively; P<0.005). In ARVD patients with complete RBBB, the most sensitive and specific parameter was an r'/s ratio <1. CONCLUSIONS: We evaluated comprehensively the diagnostic value of ECG markers for ARVD. On the basis of the findings, we propose an algorithm, with examination of QRS morphology being the first step, for ECG evaluation of ARVD patients. Definite criteria are then applied on the basis of the presence of no RBBB, incomplete RBBB, and complete RBBB to obtain the best diagnostic utility of the ECG.


Assuntos
Displasia Arritmogênica Ventricular Direita/diagnóstico , Displasia Arritmogênica Ventricular Direita/fisiopatologia , Eletrocardiografia/métodos , Eletrocardiografia/normas , Adulto , Algoritmos , Displasia Arritmogênica Ventricular Direita/epidemiologia , Bloqueio de Ramo/diagnóstico , Bloqueio de Ramo/epidemiologia , Bloqueio de Ramo/fisiopatologia , Eletrocardiografia/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
J Am Coll Cardiol ; 53(15): 1289-99, 2009 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-19358943

RESUMO

OBJECTIVES: The purpose of this study was to determine the extent of left ventricular (LV) involvement in individuals predisposed to developing arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C), and to investigate novel morphologic variants of ARVD/C. BACKGROUND: The discovery of desmosomal mutations associated with ARVD/C has led researchers to hypothesize equal right ventricular (RV) and LV affliction in the disease process. METHODS: Thirty-eight (age 30 +/- 17 years; 18 males) family members of 12 desmosomal mutation-carrying ARVD/C probands underwent genotyping and cardiac magnetic resonance imaging (CMR). The CMR investigators were blinded to clinical and genetic data. RESULTS: Twenty-five individuals had mutations in PKP2, DSP, and/or DSG2 genes. RV abnormalities were associated with the presence of mutation(s) and with disease severity determined by criteria (minor = 1; major = 2) points for ARVD/C diagnosis. The only LV abnormality detected, the presence of intramyocardial fat, was present in 4 individuals. Each of these individuals was a mutation carrier, whereas 1 had no previously described ARVD/C-related abnormality. On detailed CMR, a focal "crinkling" of the RV outflow tract and subtricuspid regions ("accordion sign") was observed in 60% of the mutation carriers and none of the noncarriers (p < 0.001). The sign was present in 0%, 37%, 71%, and 75% of individuals who met 1, 2, 3, and 4+ criteria points, respectively (p < 0.01). CONCLUSIONS: Despite a possible LV involvement in ARVD/C, the overall LV structure and function are well preserved. Independent LV involvement is of rare occurrence. The accordion sign is a promising tool for early diagnosis of ARVD/C. Its diagnostic utility should be confirmed in larger cohorts.


Assuntos
Displasia Arritmogênica Ventricular Direita/diagnóstico , Displasia Arritmogênica Ventricular Direita/genética , Imageamento por Ressonância Magnética , Adolescente , Adulto , Família , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Disfunção Ventricular Esquerda/genética , Adulto Jovem
14.
J Sep Sci ; 28(14): 1694-703, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16224963

RESUMO

Two-dimensional high performance liquid chromatography is a useful tool for proteome analysis, providing a greater peak capacity than single-dimensional LC. The most popular 2D-HPLC approach used today for proteomic research combines strong cation exchange and reversed-phase HPLC. We have evaluated an alternative mode for 2D-HPLC of peptides, employing reversed-phase columns in both separation dimensions. The orthogonality of 2D separation was investigated for selected types of RP stationary phases, ion-pairing agents and mobile phase pH. The pH appears to have the most significant impact on the RP-LC separation selectivity; the greatest orthogonality was achieved for the system with C18 columns using pH 10 in the first and pH 2.6 in the second LC dimension. Separation was performed in off-line mode with partial fraction evaporation. The achievable peak capacity in RP-RP-HPLC and overall performance compares favorably to SCX-RP-HPLC and holds promise for proteomic analysis.


Assuntos
Peptídeos/química , Peptídeos/isolamento & purificação , Proteoma/química , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Concentração de Íons de Hidrogênio , Indicadores e Reagentes
15.
Anal Chem ; 77(19): 6426-34, 2005 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16194109

RESUMO

Two-dimensional liquid chromatography is often used to reduce the proteomic sample complexity prior to tandem mass spectrometry analysis. The 2D-LC performance depends on the peak capacity in both chromatographic dimensions, and separation orthogonality. The peak capacity and selectivity of many LC modes for peptides is not well known, and mathematical characterization for orthogonality is underdeveloped. Consequently, it is difficult to estimate the performance of 2D-LC for peptide separation. The goal of this paper was to investigate a selectivity of common LC modes and to identify the 2D-LC systems with a useful orthogonality. A geometric approach for orthogonality description was developed and applied for estimation of a practical peak 2D-LC capacity. Selected LC modes including various RP, SCX, SEC, and HILIC were combined in 2D-LC setups. SCX-RP, HILIC-RP, and RP-RP 2D systems were found to provide suitable orthogonality. The RP-RP system (employing significantly different pH in both RP separation dimensions) had the highest practical peak capacity of 2D-LC systems investigated.


Assuntos
Cromatografia Líquida/métodos , Espectrometria de Massas , Peptídeos/química , Proteínas/química , Fatores de Tempo
16.
J Chromatogr A ; 1061(2): 183-92, 2004 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-15641361

RESUMO

Column peak capacity was utilized as a measure of column efficiency for gradient elution conditions. Peak capacity was evaluated experimentally for reversed-phase (RP) and cation-exchange high-performance liquid chromatography (HPLC) columns, and compared to the values predicted from RP-HPLC gradient theory. The model was found to be useful for the prediction of peak capacity and productivity in single- and two-dimensional (2D) chromatography. Both theoretical prediction and experimental data suggest that the number of peaks separated in HPLC reaches an upper limit, despite using highly efficient columns or very shallow gradients. The practical peak capacity value is about several hundred for state-of-the-art RP-HPLC columns. Doubling the column length (efficiency) improves the peak capacity by only 40%, and proportionally increases both the separation time and the backpressure. Similarly, extremely shallow gradients have a positive effect on the peak capacity, but analysis becomes unacceptably long. The model predicts that a 2D-HPLC peak capacity of 15,000 can be achieved in 8 h using multiple fraction collection in the first dimension followed by fast RP-HPLC gradients employing short, but efficient columns in the second dimension.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Peptídeos/isolamento & purificação , Modelos Teóricos , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
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