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1.
Radiology ; 278(3): 822-30, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26397127

RESUMO

PURPOSE: To determine if myeloperoxidase (MPO) is involved in epileptogenesis and if molecular nuclear imaging can be used to noninvasively map inflammatory changes in epileptogenesis. MATERIALS AND METHODS: The animal and human studies were approved by the institutional review boards. Pilocarpine-induced epileptic mice were treated with 4-aminobenzoic acid hydrazide (n = 46), a specific irreversible MPO inhibitor, or saline (n = 42). Indium-111-bis-5-hydroxytryptamide-diethylenetriaminepentaacetate was used to image brain MPO activity (n = 6 in the 4-aminobenzoic acid hydrazide and saline groups; n = 5 in the sham group) by using single photon emission computed tomography/computed tomography. The role of MPO in the development of spontaneous recurrent seizures was assessed by means of clinical symptoms and biochemical and histopathologic data. Human brain specimens from a patient with epilepsy and a patient without epilepsy were stained for MPO. The Student t test, one-way analysis of variance, and Mann-Whitney and Kruskal-Wallis tests were used. Differences were regarded as significant if P was less than .05. RESULTS: MPO and leukocytes increased in the brain during epileptogenesis (P < .05). Blocking MPO delayed spontaneous recurrent seizures (99.6 vs 142 hours, P = .016), ameliorated the severity of spontaneous recurrent seizures (P < .05), and inhibited mossy fiber sprouting (Timm index, 0.31 vs 0.03; P = .003). Matrix metalloproteinase activity was upregulated during epileptogenesis in an MPO-dependent manner (1.44 vs 0.94 U/mg, P = .049), suggesting that MPO acts upstream of matrix metalloproteinases. MPO activity was mapped during epileptogenesis in vivo in the hippocampal regions. Resected temporal lobe tissue from a human patient with refractory epilepsy but not the temporal lobe tissue from a patient without seizures demonstrated positive MPO immunostaining, suggesting high translational potential for this imaging technology. CONCLUSION: The findings of this study highlight an important role for MPO in epileptogenesis and show MPO to be a potential therapeutic target and imaging biomarker for epilepsy.


Assuntos
Epilepsia/diagnóstico por imagem , Epilepsia/enzimologia , Imagem Multimodal , Peroxidase/metabolismo , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Ácido 4-Aminobenzoico , Animais , Western Blotting , Modelos Animais de Doenças , Citometria de Fluxo , Camundongos , Pilocarpina
2.
Emerg Radiol ; 21(3): 251-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24469596

RESUMO

Evaluation of the posterior fossa (PF) on 5-mm-thick helical CT images (current default) has improved diagnostic accuracy compared to 5-mm sequential CT images; however, 5-mm-thick images may not be ideal for PF pathology due to volume averaging of rapid changes in anatomy in the Z-direction. Therefore, we sought to determine if routine review of 1.25-mm-thin helical CT images has superior accuracy in screening for nontraumatic PF pathology. MRI proof of diagnosis was obtained within 6 h of helical CT acquisition for 90 consecutive ED patients with, and 88 without, posterior fossa lesions. Helical CT images were post-processed at 1.25 and 5-mm-axial slice thickness. Two neuroradiologists blinded to the clinical/MRI findings reviewed both image sets. Interobserver agreement and accuracy were rated using Kappa statistics and ROC analysis, respectively. Of the 90/178 (51 %) who were MR positive, 60/90 (66 %) had stroke and 30/90 (33 %) had other etiologies. There was excellent interobserver agreement (κ > 0.97) for both thick and thin slice assessments. The accuracy, sensitivity, and specificity for 1.25-mm images were 65, 44, and 84 %, respectively, and for 5-mm images were 67, 45, and 85 %, respectively. The diagnostic accuracy was not significantly different (p > 0.5). In this cohort of patients with nontraumatic neurological symptoms referred to the posterior fossa, 1.25-mm-thin slice CT reformatted images do not have superior accuracy compared to 5-mm-thick images. This information has implications on optimizing resource utilizations and efficiency in a busy emergency room. Review of 1.25-mm-thin images may help diagnostic accuracy only when review of 5-mm-thick images as current default is inconclusive.


Assuntos
Encefalopatias/diagnóstico por imagem , Fossa Craniana Posterior/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Idoso , Encefalopatias/patologia , Fossa Craniana Posterior/patologia , Serviço Hospitalar de Emergência , Reações Falso-Positivas , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
3.
Stroke ; 44(12): 3344-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24172578

RESUMO

BACKGROUND AND PURPOSE: Significant stenosis of the internal carotid artery (ICA) is an established stroke risk factor. Recent evidence suggests that features within the atherosclerotic plaque also have prognostic value. The purpose of this study was to correlate the enhancement of the vasa vasorum (VV) overlying the carotid artery plaque with acute neurological symptoms in patients with 50% to 70% ICA stenosis. METHODS: We conducted a 4-year retrospective computerized tomographic angiographic review to identify patients with 50% to 70% stenosis of the ICA. Three types of plaques were identified: enhancing VV, calcified, and nonenhancing-noncalcified. Medical records were reviewed for cardiovascular risk factors and neurological status, and imaging was reviewed for signs of a recent stroke. RESULTS: We identified a total of 428 patients with 50% to 70% ICA stenosis: 103 (24.1%) had enhancing VV, 202 (47.2%) calcified, and 123 (28.7%) nonenhancing-noncalcified arteries; 97 were symptomatic and 331 asymptomatic. Thirty-three (34%) symptomatic subjects demonstrated enhancing VV, 42 (20%) had calcified arterial plaques, and 22 (17%) had nonenhancing-noncalcified arterial plaques. Fisher exact tests revealed that the proportion of symptomatic individuals with enhancing VV plaque was double that of the other groups combined (P=0.015; odds ratio, 1.92; 95% confidence interval, 1.17-3.16). Regression analyses confirmed this association as independent from other known cardiovascular risk factors. CONCLUSIONS: In patients with 50% to 70% ICA stenosis, VV enhancement recognized on computed tomographic angiography is strongly associated with acute neurological symptoms compared with calcified and nonenhancing-noncalcified arterial plaques. This finding may aid in the identification of patients at increased risk for ischemic stroke within populations with the same degree of stenosis.


Assuntos
Artéria Carótida Interna/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Vasa Vasorum/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença
4.
Radiology ; 263(2): 451-60, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22438365

RESUMO

PURPOSE: To evaluate myeloperoxidase (MPO) as a newer therapeutic target and bis-5-hydroxytryptamide-diethylenetriaminepentaacetate-gadolinium (Gd) (MPO-Gd) as an imaging biomarker for demyelinating diseases such as multiple sclerosis (MS) by using experimental autoimmune encephalomyelitis (EAE), a murine model of MS. MATERIALS AND METHODS: Animal experiments were approved by the institutional animal care committee. EAE was induced in SJL mice by using proteolipid protein (PLP), and mice were treated with either 4-aminobenzoic acid hydrazide (ABAH), 40 mg/kg injected intraperitoneally, an irreversible inhibitor of MPO, or saline as control, and followed up to day 40 after induction. In another group of SJL mice, induction was performed without PLP as shams. The mice were imaged by using MPO-Gd to track changes in MPO activity noninvasively. Imaging results were corroborated by enzymatic assays, flow cytometry, and histopathologic analyses. Significance was computed by using the t test or Mann-Whitney U test. RESULTS: There was a 2.5-fold increase in myeloid cell infiltration in the brain (P = .026), with a concomitant increase in brain MPO level (P = .0087). Inhibiting MPO activity with ABAH resulted in decrease in MPO-Gd-positive lesion volume (P = .012), number (P = .009), and enhancement intensity (P = .03) at MR imaging, reflecting lower local MPO activity (P = .03), compared with controls. MPO inhibition was accompanied by decreased demyelination (P = .01) and lower inflammatory cell recruitment in the brain (P < .0001), suggesting a central MPO role in inflammatory demyelination. Clinically, MPO inhibition significantly reduced the severity of clinical symptoms (P = .0001) and improved survival (P = .0051) in mice with EAE. CONCLUSION: MPO may be a key mediator of myeloid inflammation and tissue damage in EAE. Therefore, MPO could represent a promising therapeutic target, as well as an imaging biomarker, for demyelinating diseases and potentially for other diseases in which MPO is implicated.


Assuntos
Biomarcadores/metabolismo , Doenças Desmielinizantes/diagnóstico , Doenças Desmielinizantes/enzimologia , Encefalomielite Autoimune Experimental/diagnóstico , Encefalomielite Autoimune Experimental/enzimologia , Ressonância Magnética Nuclear Biomolecular/métodos , Peroxidase/metabolismo , Ácido 4-Aminobenzoico , Animais , Western Blotting , Meios de Contraste , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Gadolínio , Técnicas Imunoenzimáticas , Camundongos , Estatísticas não Paramétricas
6.
Hum Mol Genet ; 17(19): 2967-77, 2008 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-18614545

RESUMO

Diarrhea predominant irritable bowel syndrome (IBS-D) is a complex disorder related to dysfunctions in the serotonergic system. As cis-regulatory variants can play a role in the etiology of complex conditions, we investigated the untranslated regions (UTRs) of the serotonin receptor type 3 subunit genes HTR3A and HTR3E. Mutation analysis was carried out in a pilot sample of 200 IBS patients and 100 healthy controls from the UK. The novel HTR3E 3'-UTR variant c.*76G>A (rs62625044) was associated with female IBS-D (P = 0.033, OR = 8.53). This association was confirmed in a replication study, including 119 IBS-D patients and 195 controls from Germany (P = 0.0046, OR = 4.92). Pooled analysis resulted in a highly significant association of c.*76G>A with female IBS-D (P = 0.0002, OR = 5.39). In a reporter assay, c.*76G>A affected binding of miR-510 to the HTR3E 3'-UTR and caused elevated luciferase expression. HTR3E and miR-510 co-localize in enterocytes of the gut epithelium as shown by in situ hybridization and RT-PCR. This is the first example indicating micro RNA-related expression regulation of a serotonin receptor gene with a cis-regulatory variant affecting this regulation and appearing to be associated with female IBS-D.


Assuntos
Diarreia/genética , Síndrome do Intestino Irritável/genética , MicroRNAs/genética , Receptores de Serotonina/genética , Regiões 3' não Traduzidas/genética , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Linhagem Celular , Estudos de Coortes , Diarreia/metabolismo , Feminino , Expressão Gênica , Alemanha , Humanos , Mucosa Intestinal , Síndrome do Intestino Irritável/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação , Receptores de Serotonina/metabolismo , Receptores 5-HT3 de Serotonina , Especificidade da Espécie , Reino Unido
7.
Clin Biochem ; 40(16-17): 1225-31, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17706956

RESUMO

OBJECTIVES: To find whether the control of betaine metabolism differs between male and female patients and identify the effects of insulin and other hormones. DESIGN AND METHODS: Data from non-diabetic lipid clinic patients (82 female symbol and 76 male symbol) were re-analyzed by sex. Data on insulin, thyroid hormones and leptin were included in models to identify factors affecting the circulation and excretion of betaine and its metabolites. RESULTS: Different factors influenced plasma concentrations and urinary excretion of betaine, dimethylglycine and homocysteine in males and females. In males, apolipoprotein B (negative), thyroid stimulating hormone (positive) and insulin (negative) predicted circulating betaine, consistent with betaine-homocysteine methyltransferase mediated control. In females, insulin positively predicted plasma dimethylglycine. Urinary betaine excretion positively predicted circulating homocysteine in males (p<0.001), whereas dimethylglycine excretion (also indicating betaine loss) was a stronger positive predictor (p<0.001) in females. Carnitine affected betaine homeostasis. CONCLUSIONS: Betaine metabolism is under endocrine control, and studies should use sex stratified groups.


Assuntos
Betaína/sangue , Betaína/urina , Transtornos do Metabolismo dos Lipídeos/sangue , Transtornos do Metabolismo dos Lipídeos/urina , Adulto , Betaína-Homocisteína S-Metiltransferase/metabolismo , Carnitina/sangue , Carnitina/urina , Feminino , Homocisteína/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Sarcosina/análogos & derivados , Sarcosina/sangue , Sarcosina/urina , Fatores Sexuais , Hormônios Tireóideos/sangue
8.
Clin Biochem ; 40(11): 798-801, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17490630

RESUMO

OBJECTIVES: Does abnormal betaine excretion persist? DESIGN AND METHODS: Patients (10) with abnormal excretion in 1998 were recalled in 2005. Subsequent urine samples were collected on 4 days from persistently abnormal subjects. RESULTS: Half the 1998 abnormal patients were abnormal in 2005. Only 1/20 controls was abnormal (p=0.015). All patients with abnormal excretion in 1998 and 2005 had abnormal excretion on successive days while no controls did. CONCLUSIONS: High betaine excretion may be chronic and a health risk.


Assuntos
Betaína/urina , Idoso , Doença Crônica , Feminino , Seguimentos , Humanos , Masculino , Fatores de Tempo
9.
Clin Biochem ; 40(7): 447-53, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17335790

RESUMO

OBJECTIVES: To establish whether normal human subjects excrete glycine betaine at a constant rate. DESIGN AND METHODS: Urine was collected from ten normal healthy male subjects for 14 days, during which fluid intake was systematically varied from <800 mL to >3 L per day. Glycine betaine, sorbitol and creatinine excretions were estimated per day and as millimole per mol creatinine. RESULTS: The intrasubject SD of urine glycine betaine was 3.5 mmol/mol creatinine, and the intersubject SD 5.8 mmol/mol creatinine. The intrasubject SD of plasma glycine betaine was 10.2 mol/L and the intersubject SD 14.2 mol/L. Water load had little effect on glycine betaine excretion and plasma glycine betaine. After 12 years, excretions and plasma concentrations tended to parallel the initial results. CONCLUSIONS: Normal subjects have consistent individual glycine betaine excretions that are not strongly influenced by urine volume. Abnormal excretions, or significant changes in excretion, can be interpreted as indicating a pathological process.


Assuntos
Betaína/urina , Creatinina/urina , Sorbitol/urina , Adulto , Fatores Etários , Betaína/sangue , Cromatografia Líquida de Alta Pressão , Humanos , Masculino , Fatores de Tempo
10.
Clin Ther ; 28(4): 569-81, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16750468

RESUMO

BACKGROUND: Phase IIb studies have reported that cilomilast, a selective phosphodiesterase 4 inhibitor being developed for the treatment of chronic obstructive pulmonary disease, is associated with gastrointestinal (GI) adverse effects (AEs) in a small proportion (approximately 5%) of individuals. OBJECTIVES: The aims of these 2 studies were to investigate the effects of cilomilast 15 mg BID on: (1) lower esophageal sphincter pressure (LESP) and esophageal body motility and pH (study 1); and (2) orocecal and whole-gut transit times (OCTT and WGTT, respectively) (study 2) in healthy volunteers. METHODS: These 2 randomized, double-blind, placebo-controlled, 2-part crossover studies were conducted at the Neurogastroenterology Unit, Wythenshawe Hospital, Manchester, United Kingdom (study 1) and GlaxoSmithKline, Harlow, United Kingdom (study 2). In study 1, subjects were randomly assigned to receive either cilomilast (15 mg BID) or matched placebo (control) for 7 days (13 doses; subjects were not given the evening dose on day 7), and in study 2, cilomilast (15 mg BID) or matched placebo (control) for 9 days (18 doses) in each of 2 treatment periods. After study drug administration, combined esophageal motility and pH were recorded for 2 hours before and 4 hours after the administration of a standardized meal (2400 kJ [573 kcal]). Sequences of 6 consecutive 5-mL water swallows (separated by 20 seconds) were carried out 60 and 90 minutes (fasting) and 150, 180, 210, 240, 300, and 360 minutes (fed) after study drug administration. OCTT was determined from the increase in breath hydrogen after the meal. WGTT was determined from the time taken to excrete at least 16 of 20 ingested radiopaque markers, ingested as 2 capsules, each containing 10 radiopaque markers, with 240 mL of water. AEs were elicited at specified times throughout each session using nonleading questions, spontaneously reported AEs, and diary cards. RESULTS: Study 1 enrolled 20 subjects (11 men, 9 women; age range, 20-52 years). Study 2 enrolled 16 subjects (10 men, 6 women; age range, 19-48 years). No clinically significant differences in the amplitude (mean difference in postprandial-preprandial AUC0-t/t, 6.09 mm Hg; 95% CI, -10.66 to 22.84), duration (difference, -0.08 second; 95% CI, -0.54 to 0.37), or velocity of propagation (difference, 0.90 cm/s; 95% CI, -0.66 to 2.46) of esophageal contractions, LESP (difference, -0.39 mm Hg; 95% CI, -5.23 to 4.45), or preprandial or postprandial percentage time pH<4 (median differences: preprandial, 0.47% [95% CI, -0.45 to 1.27]; postprandial, -0.005% [95% CI, -1.30 to 6.27]) were found with cilomilast compared with placebo. No significant differences in OCTT (difference, -0.37 hour; 95% CI, -1.59 to 0.84) or WGTT (difference, -2.96 hours; 95% CI, -20.76 to 14.84) were found with cilomilast compared with controls. In both studies, the most frequently reported AEs with cilomilast use were nausea (8/18 in study 1 and 3/16 in study 2) and headache (8/18 in study 1 and 6/16 in study 2); however, these were generally of mild to moderate intensity. Overall, GI AEs did not correlate with changes in GI motility. CONCLUSION: The results of these 2 studies suggest that cilomilast was not associated with significant changes in esophageal motility and pH or GI transit in these healthy volunteers.


Assuntos
3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Esôfago/efeitos dos fármacos , Motilidade Gastrointestinal/efeitos dos fármacos , Trânsito Gastrointestinal/efeitos dos fármacos , Nitrilas/farmacologia , Inibidores de Fosfodiesterase/farmacologia , Adulto , Área Sob a Curva , Ácidos Carboxílicos/efeitos adversos , Ácidos Carboxílicos/farmacologia , Ceco/efeitos dos fármacos , Estudos Cross-Over , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Ácidos Cicloexanocarboxílicos , Método Duplo-Cego , Esfíncter Esofágico Inferior/efeitos dos fármacos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Manometria , Pessoa de Meia-Idade , Nitrilas/efeitos adversos , Inibidores de Fosfodiesterase/efeitos adversos
11.
Artigo em Inglês | MEDLINE | ID: mdl-16442351

RESUMO

A sensitive and rapid assay is described for the measurement of low concentrations of 5-hydroxytryptamine (5-HT) present in human platelet-depleted plasma (PDP) using reverse-phase high performance liquid chromatography (HPLC) with fluorimetric detection. With an analysis time of 12 min, this method is particularly useful for large-scale clinical trials investigating small differences in PDP 5-HT concentrations in conditions such as functional gastrointestinal disorders (FGID). The limit of detection and quantification were 1 and 3 nmol/l, respectively, and the calibration curve linear between 1 and 1000 nmol/l. The within-day and between-day precision were 4.3 and <13.6%, respectively.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Serotonina/sangue , Humanos , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Fluorescência
12.
Abdom Radiol (NY) ; 41(7): 1338-48, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27315095

RESUMO

PURPOSE: The goal of this study is to evaluate the diagnostic performance of simultaneous FDG-PET/MR including diffusion compared to FDG-PET/CT in patients with lymphoma. METHODS: Eighteen patients with a confirmed diagnosis of non-Hodgkin's (NHL) or Hodgkin's lymphoma (HL) underwent an IRB-approved, single-injection/dual-imaging protocol consisting of a clinical FDG-PET/CT and subsequent FDG-PET/MR scan. PET images from both modalities were reconstructed iteratively. Attenuation correction was performed using low-dose CT data for PET/CT and Dixon-MR sequences for PET/MR. Diffusion-weighted imaging was performed. SUVmax was measured and compared between modalities and the apparent diffusion coefficient (ADC) using ROI analysis by an experienced radiologist using OsiriX. Strength of correlation between variables was measured using the Pearson correlation coefficient (r p). RESULTS: Of the 18 patients included in this study, 5 had HL and 13 had NHL. The median age was 51 ± 14.8 years. Sixty-five FDG-avid lesions were identified. All FDG-avid lesions were visible with comparable contrast, and therefore initial and follow-up staging was identical between both examinations. SUVmax from FDG-PET/MR [(mean ± sem) (21.3 ± 2.07)] vs. FDG-PET/CT (mean 23.2 ± 2.8) demonstrated a strongly positive correlation [r s = 0.95 (0.94, 0.99); p < 0.0001]. There was no correlation found between ADCmin and SUVmax from FDG-PET/MR [r = 0.17(-0.07, 0.66); p = 0.09]. CONCLUSION: FDG-PET/MR offers an equivalent whole-body staging examination as compared with PET/CT with an improved radiation safety profile in lymphoma patients. Correlation of ADC to SUVmax was weak, understating their lack of equivalence, but not undermining their potential synergy and differing importance.


Assuntos
Doença de Hodgkin/diagnóstico por imagem , Linfoma não Hodgkin/diagnóstico por imagem , Imagem Multimodal , Imagem de Difusão por Ressonância Magnética , Feminino , Fluordesoxiglucose F18 , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos
13.
Obstet Gynecol ; 99(5 Pt 2): 882-5, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11975944

RESUMO

BACKGROUND: Most cardiomyopathies recognizable in utero are the dilated type-with dilated, poorly contractile left ventricle. We propose a diagnostic criterion for the rare spongiform (noncompacted) cardiomyopathy. CASES: Three perinatal cases with echocardiography and autopsy are presented. The apical ventricular myocardium was thickened and markedly trabeculated. The ventricles were not dilated in two, and the atria were enlarged in all. Hydrops and bradycardia were present in all three despite normal or only mildly diminished contractility. Although the cardiomyopathy was familial in two siblings, two of three cases were female, ruling out Barth syndrome (with sex-linked recessive inheritance). Although all three of our cases with hydrops died, rare survivors have been reported in the eighth decade. CONCLUSION: Although spongiform cardiomyopathy may eventually develop into a dilated cardiomyopathy, its early characteristic is relatively diagnostic: a restrictive cardiomyopathy with no enlargement of the ventricles and prominent atria.


Assuntos
Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/patologia , Doenças Fetais/diagnóstico por imagem , Doenças Fetais/patologia , Coração Fetal/diagnóstico por imagem , Coração Fetal/patologia , Autopsia , Ecocardiografia , Feminino , Morte Fetal , Idade Gestacional , Humanos , Masculino , Gravidez , Terceiro Trimestre da Gravidez , Diagnóstico Pré-Natal
14.
PLoS One ; 9(12): e114969, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25493436

RESUMO

BACKGROUND: Betaine is a major osmolyte, also important in methyl group metabolism. Concentrations of betaine, its metabolite dimethylglycine and analog trimethylamine-N-oxide (TMAO) in blood are cardiovascular risk markers. Diabetes disturbs betaine: does diabetes alter associations between betaine-related measures and cardiovascular risk? METHODS: Plasma samples were collected from 475 subjects four months after discharge following an acute coronary admission. Death (n = 81), secondary acute MI (n = 87), admission for heart failure (n = 85), unstable angina (n = 72) and all cardiovascular events (n = 283) were recorded (median follow-up: 1804 days). RESULTS: High and low metabolite concentrations were defined as top or bottom quintile of the total cohort. In subjects with diabetes (n = 79), high plasma betaine was associated with increased frequencies of events; significantly for heart failure, hazard ratio 3.1 (1.2-8.2) and all cardiovascular events, HR 2.8 (1.4-5.5). In subjects without diabetes (n = 396), low plasma betaine was associated with events; significantly for secondary myocardial infarction, HR 2.1 (1.2-3.6), unstable angina, HR 2.3 (1.3-4.0), and all cardiovascular events, HR 1.4 (1.0-1.9). In diabetes, high TMAO was a marker of all outcomes, HR 2.7 (1.1-7.1) for death, 4.0 (1.6-9.8) for myocardial infarction, 4.6 (2.0-10.7) for heart failure, 9.1 (2.8-29.7) for unstable angina and 2.0 (1.1-3.6) for all cardiovascular events. In subjects without diabetes TMAO was only significant for death, HR 2.7 (1.6-4.8) and heart failure, HR 1.9 (1.1-3.4). Adding the estimated glomerular filtration rate to Cox regression models tended to increase the apparent risks associated with low betaine. CONCLUSIONS: Elevated plasma betaine concentration is a marker of cardiovascular risk in diabetes; conversely low plasma betaine concentrations indicate increased risk in the absence of diabetes. We speculate that the difference reflects control of osmolyte retention in tissues. Elevated plasma TMAO is a strong risk marker in diabetes.


Assuntos
Betaína/sangue , Doenças Cardiovasculares/sangue , Diabetes Mellitus Tipo 2/sangue , Metilaminas/sangue , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/complicações , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Risco
15.
PLoS One ; 7(3): e33671, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22457780

RESUMO

An alternative hypothesis has been proposed implicating chronic cerebrospinal venous insufficiency (CCSVI) as a potential cause of multiple sclerosis (MS). We aimed to evaluate the validity of this hypothesis in a controlled animal model. Animal experiments were approved by the institutional animal care committee. The jugular veins in SJL mice were ligated bilaterally (n = 20), and the mice were observed for up to six months after ligation. Sham-operated mice (n = 15) and mice induced with experimental autoimmune encephalomyelitis (n = 8) were used as negative and positive controls, respectively. The animals were evaluated using CT venography and (99m)Tc-exametazime to assess for structural and hemodynamic changes. Imaging was performed to evaluate for signs of blood-brain barrier (BBB) breakdown and neuroinflammation. Flow cytometry and histopathology were performed to assess inflammatory cell populations and demyelination. There were both structural changes (stenosis, collaterals) in the jugular venous drainage and hemodynamic disturbances in the brain on Tc99m-exametazime scintigraphy (p = 0.024). In the JVL mice, gadolinium MRI and immunofluorescence imaging for barrier molecules did not reveal evidence of BBB breakdown (p = 0.58). Myeloperoxidase, matrix metalloproteinase, and protease molecular imaging did not reveal signs of increased neuroinflammation (all p>0.05). Flow cytometry and histopathology also did not reveal increase in inflammatory cell infiltration or population shifts. No evidence of demyelination was found, and the mice remained without clinical signs. Despite the structural and hemodynamic changes, we did not identify changes in the BBB permeability, neuroinflammation, demyelination, or clinical signs in the JVL group compared to the sham group. Therefore, our murine model does not support CCSVI as a cause of demyelinating diseases such as multiple sclerosis.


Assuntos
Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/patologia , Encefalomielite Autoimune Experimental/patologia , Veias Jugulares/patologia , Animais , Barreira Hematoencefálica , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Imageamento por Ressonância Magnética , Camundongos , Microscopia de Fluorescência , Cintilografia
16.
PLoS One ; 7(3): e32460, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22396767

RESUMO

BACKGROUND: Urinary betaine excretion positively correlated with plasma homocysteine in outpatients attending a lipid disorders clinic (lipid clinic study). We aimed to confirm this in subjects with established vascular disease. METHODS: The correlation between betaine excretion and homocysteine was compared in samples collected from subjects 4 months after hospitalization for an acute coronary episode (ACS study, 415 urine samples) and from 158 sequential patients visiting a lipid disorders clinic. PRINCIPAL FINDINGS: In contrast to the lipid clinic study, betaine excretion and plasma homocysteine did not correlate in the total ACS cohort. Differences between the patient groups included age, non-HDL cholesterol and medication. In ACS subjects with below median betaine excretion, excretion correlated (using log transformed data) negatively with plasma homocysteine (r = -0.17, p = 0.019, n = 199), with no correlation in the corresponding subset of the lipid clinic subjects. In ACS subjects with above median betaine excretion a positive trend (r = +0.10) between betaine excretion and homocysteine was not significant; the corresponding correlation in lipid clinic subjects was r = +0.42 (p = 0.0001). In ACS subjects, correlations were stronger when plasma non-HDL cholesterol and betaine excretion were above the median, r = +0.20 (p = 0.045); in subjects above median non-HDL cholesterol and below median betaine excretion, r = -0.26 (p = 0.012). ACS subjects taking diuretics or proton pump inhibitors had stronger correlations, negative with lower betaine excretion and positive with higher betaine excretion. CONCLUSIONS: Betaine excretion correlates with homocysteine in subjects with elevated blood lipids.


Assuntos
Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/urina , Betaína/metabolismo , Homocisteína/metabolismo , Transtornos do Metabolismo dos Lipídeos/sangue , Transtornos do Metabolismo dos Lipídeos/urina , Lipídeos/sangue , Doenças Vasculares/sangue , Doenças Vasculares/urina , Adulto , Idoso , Idoso de 80 Anos ou mais , Betaína/urina , Colesterol/sangue , Estudos de Coortes , Feminino , Homocisteína/sangue , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Reprodutibilidade dos Testes , Projetos de Pesquisa
17.
PLoS One ; 7(5): e37883, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22649561

RESUMO

BACKGROUND: Betaine insufficiency is associated with unfavourable vascular risk profiles in metabolic syndrome patients. We investigated associations between betaine insufficiency and secondary events in acute coronary syndrome patients. METHODS: Plasma (531) and urine (415) samples were collected four months after discharge following an acute coronary event. Death (34), secondary acute myocardial infarction (MI) (70) and hospital admission for heart failure (45) events were recorded over a median follow-up of 832 days. PRINCIPAL FINDINGS: The highest and lowest quintiles of urinary betaine excretion associated with risk of heart failure (p = 0.0046, p = 0.013 compared with middle 60%) but not with subsequent acute MI. The lowest quintile of plasma betaine was associated with subsequent acute MI (p = 0.014), and the top quintile plasma betaine with heart failure (p = 0.043), especially in patients with diabetes (p<0.001). Top quintile plasma concentrations of dimethylglycine (betaine metabolite) and top quintile plasma homocysteine both associated with all three outcomes, acute MI (p = 0.004, <0.001), heart failure (p = 0.027, p<0.001) and survival (p<0.001, p<0.001). High homocysteine was associated with high or low betaine excretion in >60% of these subjects (p = 0.017). Median NT-proBNP concentrations were lowest in the middle quintile of plasma betaine concentration (p = 0.002). CONCLUSIONS: Betaine insufficiency indicates increased risk of secondary heart failure and acute MI. Its association with elevated homocysteine may partly explain the disappointing results of folate supplementation. In some patients, especially with diabetes, elevated plasma betaine also indicates increased risk.


Assuntos
Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/urina , Betaína/sangue , Betaína/urina , Insuficiência Cardíaca/etiologia , Infarto do Miocárdio/etiologia , Idoso , Idoso de 80 Anos ou mais , Betaína/metabolismo , Cromatografia Líquida de Alta Pressão , Estudos de Coortes , Feminino , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/urina , Homocisteína/sangue , Humanos , Estimativa de Kaplan-Meier , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/urina , Nova Zelândia , Fatores de Risco , Sarcosina/análogos & derivados , Sarcosina/sangue
18.
PLoS One ; 6(7): e21666, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21747945

RESUMO

BACKGROUND: Low plasma betaine has been associated with unfavorable plasma lipid profiles and cardiovascular risk. In some studies raised plasma betaine after supplementation is associated with elevations in plasma lipids. We aimed to measure the relationships between plasma and urine betaine and plasma lipids, and the effects of lipid-lowering drugs on these. METHODOLOGY: Fasting plasma samples were collected from 531 subjects (and urine samples from 415) 4 months after hospitalization for an acute coronary syndrome episode. In this cross-sectional study, plasma betaine and dimethylglycine concentrations and urine excretions were compared with plasma lipid concentrations. Subgroup comparisons were made for gender, with and without diabetes mellitus, and for drug treatment. PRINCIPAL FINDINGS: Plasma betaine negatively correlated with triglyceride (Spearman's r(s) = -0.22, p<0.0001) and non-high-density lipoprotein cholesterol (r(s) = -0.27, p<0.0001). Plasma betaine was a predictor of BMI (p<0.05) and plasma non-high-density lipoprotein cholesterol and triglyceride (p<0.001) independently of gender, age and the presence of diabetes. Using data grouped by plasma betaine decile, increasing plasma betaine was linearly related to decreases in BMI (p = 0.008) and plasma non-HDL cholesterol (p = 0.002). In a non-linear relationship betaine was negatively associated with elevated plasma triglycerides (p = 0.004) only for plasma betaine >45 µmol/L. Subjects taking statins had higher plasma betaine concentrations (p<0.001). Subjects treated with a fibrate had lower plasma betaine (p = 0.003) possibly caused by elevated urine betaine loss (p<0.001). The ratio of coenzyme Q to non-high-density lipoprotein cholesterol was higher in subjects with higher plasma betaine, and in subjects taking a statin. CONCLUSION: Low plasma betaine concentrations correlated with an unfavourable lipid profile. Betaine deficiency may be common in the study population. Controlled clinical trials of betaine supplementation should be conducted in appropriate populations to determine whether correction affects cardiovascular risk.


Assuntos
Síndrome Coronariana Aguda/sangue , Betaína/sangue , Lipídeos/sangue , Síndrome Coronariana Aguda/urina , Idoso , Idoso de 80 Anos ou mais , Betaína/metabolismo , Betaína/urina , Estudos de Coortes , Complicações do Diabetes/sangue , Complicações do Diabetes/urina , Suplementos Nutricionais , Feminino , Humanos , Hipolipemiantes/farmacologia , Masculino , Pessoa de Meia-Idade , Sarcosina/análogos & derivados , Sarcosina/sangue , Sarcosina/metabolismo
19.
Eur J Gastroenterol Hepatol ; 22(7): 856-61, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19561511

RESUMO

BACKGROUND: Conflicting data exist on the association between functional polymorphisms in the serotonin reuptake transporter (SERT) gene (SLC6A4) and irritable bowel syndrome (IBS). This may be partly because of small participant numbers and varying ethnic origin and sex within the cohorts studied. AIM: To reassess the potential association between the SERT polymorphisms 5-HTTLPR and STin2 in both male and female IBS patients with diarrhoea (IBS-D) and constipation (IBS-C) compared with healthy volunteers. METHODS: In this case-control study, 196 Caucasian Rome II IBS patients [97 IBS-D (aged 18-66 years; 67 female) and 99 IBS-C (aged 18-65 years; 95 female)] and 92 Caucasian healthy volunteers (aged 18-63 years; 60 female) from the UK had genomic DNA extracted from peripheral blood and the 5-HTTLPR and STin2 polymorphisms genotyped. RESULTS: The frequency of the 5-HTTLPR (ss) genotype was slightly lower in both IBS-D (16.5%) and IBS-C (14.3%) patients compared with controls (23.9%), although not significantly (P

Assuntos
Síndrome do Intestino Irritável/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Constipação Intestinal/genética , Diarreia/genética , Feminino , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Fatores Sexuais , Adulto Jovem
20.
Clin Biochem ; 42(7-8): 706-12, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19217890

RESUMO

OBJECTIVES: We aimed to compare the individuality (within subject consistency) of plasma and urine betaine and N,N-dimethylglycine. DESIGN AND METHODS: In two separate groups of 8 males (ages 19 to 40), plasma (10) and urine (6) samples were collected either over a single day or over an 8 week period. The individuality of the betaine and N,N-dimethylglycine plasma concentrations and excretions were estimated by one-way repeated measures analysis of variance. The reliability coefficients and indices of individuality were calculated. The between-subject variation in the study population was compared with that in a normal population (n=192 for plasma, 205 for urine). RESULTS: Plasma betaine concentrations were significantly different between subjects over 24 h and 8 weeks (p<0.00001). Plasma dimethylglycine concentrations were different over 24 h. Urine betaine and dimethylglycine excretions were different in both (p<0.0001). Betaine was more individual than dimethylglycine in both plasma and urine. Compared with a normal healthy population, the between-subject variation in plasma betaine was less (p<0.001) in the study group, but similar for dimethylglycine and for urine betaine. CONCLUSIONS: Plasma betaine and urinary betaine excretions are more individual than dimethylglycine. Plasma and urine betaine are highly individual in the general population.


Assuntos
Betaína/sangue , Betaína/urina , Sarcosina/análogos & derivados , Adulto , Betaína/administração & dosagem , Cromatografia Líquida de Alta Pressão , Suplementos Nutricionais , Feminino , Humanos , Masculino , Sarcosina/administração & dosagem , Sarcosina/sangue , Sarcosina/urina , Fatores de Tempo , Adulto Jovem
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