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1.
Mol Cell Proteomics ; 18(10): 2121-2137, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31324658

RESUMO

Exposure of blood plasma/serum (P/S) to thawed conditions (> -30 °C) can produce biomolecular changes that skew measurements of biomarkers within archived patient samples, potentially rendering them unfit for molecular analysis. Because freeze-thaw histories are often poorly documented, objective methods for assessing molecular fitness before analysis are needed. We report a 10-µl, dilute-and-shoot, intact-protein mass spectrometric assay of albumin proteoforms called "ΔS-Cys-Albumin" that quantifies cumulative exposure of archived P/S samples to thawed conditions. The relative abundance of S-cysteinylated (oxidized) albumin in P/S increases inexorably but to a maximum value under 100% when samples are exposed to temperatures > -30 °C. The difference in the relative abundance of S-cysteinylated albumin (S-Cys-Alb) before and after an intentional incubation period that drives this proteoform to its maximum level is denoted as ΔS-Cys-Albumin. ΔS-Cys-Albumin in fully expired samples is zero. The range (mean ± 95% CI) observed for ΔS-Cys-Albumin in fresh cardiac patient P/S (n = 97) was, for plasma 12-29% (20.9 ± 0.75%) and for serum 10-24% (15.5 ± 0.64%). The multireaction rate law that governs S-Cys-Alb formation in P/S was determined and shown to predict the rate of formation of S-Cys-Alb in plasma and serum samples-a step that enables back-calculation of the time at which unknown P/S specimens have been exposed to room temperature. A blind challenge demonstrated that ΔS-Cys-Albumin can detect exposure of groups (n = 6 each) of P/S samples to 23 °C for 2 h, 4 °C for 16 h, or -20 °C for 24 h-and exposure of individual specimens for modestly increased times. An unplanned case study of nominally pristine serum samples collected under NIH-sponsorship demonstrated that empirical evidence is required to ensure accurate knowledge of archived P/S biospecimen storage history.


Assuntos
Biomarcadores/análise , Plasma/química , Soro/química , Cisteína/química , Congelamento , Humanos , Espectrometria de Massas , Albumina Sérica/química
2.
Case Rep Cardiol ; 2017: 7630915, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29209541

RESUMO

Ebstein's anomaly is a rare congenital heart disease that presents with apical displacement of the septal and posterior leaflets of the tricuspid valve. It has a wide spectrum of clinical presentations and has been shown to manifest itself any time from birth to adulthood. Our patient is a 43-year-old male with a history of intravenous heroin abuse who presented to the emergency department with worsening shortness of breath and lower extremity edema. He denied any prior cardiac history. A transthoracic echo showed normal left ventricular function, but a large 2.2 × 2.1 cm echodensity on the septal leaflet of the tricuspid valve consistent with vegetation with severe tricuspid regurgitation and probable leaflet perforation. It also demonstrated severe right heart enlargement with atrialization of the right ventricle and apical displacement of the tricuspid valve consistent with Ebstein's anomaly. This is a rare case of an adult who presented with asymptomatic Ebstein's anomaly. There have been few reports of tricuspid valve endocarditis with Ebstein's anomaly in the literature. To our knowledge, this represents the fifth reported case of a new diagnosis of Ebstein's anomaly in the setting of endocarditis and the second case of Ebstein's anomaly and endocarditis in an intravenous drug abuser.

3.
Am J Case Rep ; 17: 553-8, 2016 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-27484990

RESUMO

BACKGROUND Non-neoplastic causes such as infections and thrombi account for most intracardiac masses. Primary tumors such as myxomas and metastasis from breast cancer, lung cancer, or melanomas account for many of the remaining cases. Burkitt lymphoma manifesting as an intracardiac mass is a rare entity, with 21 cases reported in the English literature. CASE REPORT We report the case of a man infected with human immunodeficiency virus (HIV) who presented with non-specific cardiac symptoms and was later found to have intracardiac mass caused by Burkitt lymphoma. His rapid decline with unexpected complications was reversed with prompt management. Subsequent to induction, the patient achieved a near complete response with considerable improvement in his condition. CONCLUSIONS Lymphoma should be considered in the differential diagnosis of intracardiac masses. Associated cardiac symptoms are frequently non-specific and can often be overlooked or underappreciated. Burkitt lymphoma has a short doubling time and an intracardiac lesion can become life-threatening in a matter of days. Early recognition and prompt treatment are crucial to achieving optimal outcomes.


Assuntos
Linfoma de Burkitt/diagnóstico por imagem , Neoplasias Cardíacas/diagnóstico por imagem , Adulto , Linfoma de Burkitt/complicações , Linfoma de Burkitt/terapia , Ecocardiografia Tridimensional , Infecções por HIV/complicações , Neoplasias Cardíacas/complicações , Neoplasias Cardíacas/terapia , Humanos , Masculino , Tomografia Computadorizada por Raios X
4.
Mol Cell Proteomics ; 13(7): 1890-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24736286

RESUMO

S-cysteinylated albumin and methionine-oxidized apolipoprotein A-I (apoA-I) have been posed as candidate markers of diseases associated with oxidative stress. Here, a dilute-and-shoot form of LC-electrospray ionization-MS requiring half a microliter of blood plasma was employed to simultaneously quantify the relative abundance of these oxidized proteoforms in samples stored at -80 °C, -20 °C, and room temperature and exposed to multiple freeze-thaw cycles and other adverse conditions in order to assess the possibility that protein oxidation may occur as a result of poor sample storage or handling. Samples from a healthy donor and a participant with poorly controlled type 2 diabetes started at the same low level of protein oxidation and behaved similarly; significant increases in albumin oxidation via S-cysteinylation were found to occur within hours at room temperature and days at -20 °C. Methionine oxidation of apoA-I took place on a longer time scale, setting in after albumin oxidation reached a plateau. Freeze-thaw cycles had a minimal effect on protein oxidation. In matched collections, protein oxidation in serum was the same as that in plasma. Albumin and apoA-I oxidation were not affected by sample headspace or the degree to which vials were sealed. ApoA-I, however, was unexpectedly found to oxidize faster in samples with lower surface-area-to-volume ratios. An initial survey of samples from patients with inflammatory conditions normally associated with elevated oxidative stress-including acute myocardial infarction and prostate cancer-demonstrated a lack of detectable apoA-I oxidation. Albumin S-cysteinylation in these samples was consistent with known but relatively brief exposures to temperatures above -30 °C (the freezing point of blood plasma). Given their properties and ease of analysis, these oxidized proteoforms, once fully validated, may represent the first markers of blood plasma specimen integrity based on direct measurement of oxidative molecular damage that can occur under suboptimal storage conditions.


Assuntos
Apolipoproteína A-I/análise , Cisteína/química , Metionina/química , Estresse Oxidativo , Albumina Sérica/análise , Apolipoproteína A-I/sangue , Apolipoproteína A-I/metabolismo , Cromatografia Líquida , Criopreservação/métodos , Diabetes Mellitus Tipo 2 , Congelamento , Humanos , Masculino , Infarto do Miocárdio , Oxirredução , Neoplasias da Próstata , Albumina Sérica/metabolismo , Manejo de Espécimes , Espectrometria de Massas por Ionização por Electrospray
5.
J Am Soc Echocardiogr ; 21(10): 1178.e5-6, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18313265

RESUMO

Ventricular septal defects are one of the most common congenital heart defects that either exist alone or coexist with other complex congenital heart diseases. With 3-dimensional echocardiography, exact 3-dimensional shape, size, location, and course of any ventricular septal defects can be evaluated very thoroughly. We are reporting a comprehensive assessment of a complex ventricular septal defect using 3-dimensional echocardiography and longitudinal strain analysis.


Assuntos
Ecocardiografia Tridimensional/métodos , Comunicação Interventricular/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Adulto , Diagnóstico Diferencial , Comunicação Interventricular/classificação , Humanos , Masculino
6.
J Am Soc Echocardiogr ; 16(4): 347-54, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12712017

RESUMO

OBJECTIVE: We sought to validate and evaluate 2 novel intraoperative ultrasound probes for epicoronary and epiaortic imaging. BACKGROUND: The noninvasive intraoperative assessment of successful coronary artery bypass grafting remains a challenge. METHODS: A total of 19 consecutive patients (4 female, 15 male; mean age 60.5 +/- 13.8 years SD, range 34-84) underwent coronary artery bypass grafting. The epivascular probes (GE Ultrasound) were validated in vitro and intraoperatively. Coronary arteries, grafts, and ascending aorta were imaged and quantified. RESULTS: Mean adjusted flow measured by flowmeter was 3.25 L, SE 0.47 (range: 1-5.5 L) and was 3.15 L, SE 0.46 (range: 1-5.0 L) by ultrasound, with r = 0.97, P <.0001. Intraoperatively, 56 native coronary vessels were bypassed using 15 left internal mammary artery grafts, 25 vein grafts, and 16 venous jump grafts. A total of 15 left internal mammary artery grafts (100%), 12 left internal mammary artery anastomoses (80%), 20 vein grafts (15 left anterior descending coronary arteries, left circumflex artery grafts, 5 right coronary artery grafts) (80%), 4 jump grafts (25%), and 15 ascending aortas (78%) were successfully imaged by inexperienced surgeons. Doppler flow measurements were possible in 50 vessels (89%). Mean lumen diameter for graft arteries (veins) was 2 mm (2.87 mm), maximal velocity was 72 cm/s (46 cm/s), and mean velocity was 29 cm/s (21 cm/s) with a mean flow rate of 70 mL/m (55 mL/m). CONCLUSIONS: We conclude that: (1) the novel intraoperative probes measure validated flow; (2) intraoperative hemodynamic assessment of graft patency is feasible without a learning curve; and (3) these findings should encourage the routine use of these intraoperative epivascular digital ultrasound probes.


Assuntos
Ponte de Artéria Coronária , Doença das Coronárias/cirurgia , Vasos Coronários/diagnóstico por imagem , Ecocardiografia/instrumentação , Oclusão de Enxerto Vascular/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo , Circulação Coronária , Doença das Coronárias/fisiopatologia , Vasos Coronários/fisiologia , Ecocardiografia Doppler/instrumentação , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/instrumentação , Monitorização Intraoperatória/métodos , Grau de Desobstrução Vascular
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