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1.
PLoS One ; 13(12): e0208534, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30532219

RESUMO

OBJECTIVE: The objective was to predict insufficient response to 3 months methotrexate (MTX) in DMARD naïve rheumatoid arthritis patients. METHODS: A Multivariable logistic regression model of rheumatoid arthritis patients starting MTX was developed in a derivation cohort with 285 patients starting MTX in a clinical multicentre, stratified single-blinded trial, performed in seven secondary care clinics and a tertiary care clinic. The model was validated in a validation cohort with 102 patients starting MTX at a tertiary care clinic. Outcome was insufficient response (disease activity score (DAS)28 >3.2) after 3 months of MTX treatment. Clinical characteristics, lifestyle variables, genetic and metabolic biomarkers were determined at baseline in both cohorts. These variables were dichotomized and used to construct a multivariable prediction model with backward logistic regression analysis. RESULTS: The prediction model for insufficient response in the derivation cohort, included: DAS28>5.1, Health Assessment Questionnaire>0.6, current smoking, BMI>25 kg/m2, ABCB1 rs1045642 genotype, ABCC3 rs4793665 genotype, and erythrocyte-folate<750 nmol/L. In the derivation cohort, AUC of ROC curve was 0.80 (95%CI: 0.73-0.86), and 0.80 (95%CI: 0.69-0.91) in the validation cohort. Betas of the prediction model were transformed into total risk score (range 0-8). At cutoff of ≥4, probability for insufficient response was 44%. Sensitivity was 71%, specificity 72%, with positive and negative predictive value of 72% and 71%. CONCLUSIONS: A prognostics prediction model for insufficient response to MTX in 2 prospective RA cohorts by combining genetic, metabolic, clinical and lifestyle variables was developed and validated. This model satisfactorily identified RA patients with high risk of insufficient response to MTX.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Metotrexato/uso terapêutico , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Adulto , Área Sob a Curva , Artrite Reumatoide/patologia , Estudos de Coortes , Feminino , Ácido Fólico/análise , Ácido Fólico/sangue , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Polimorfismo de Nucleotídeo Único , Valor Preditivo dos Testes , Prognóstico , Curva ROC , Fatores de Risco , Resultado do Tratamento
2.
PLoS One ; 12(10): e0182472, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29084233

RESUMO

BACKGROUND: DNA methylation is affected by the activities of the key enzymes and intermediate metabolites of the one-carbon pathway, one of which involves homocysteine. We investigated the effect of the well-known genetic variant associated with mildly elevated homocysteine: MTHFR 677C>T independently and in combination with other homocysteine-associated variants, on genome-wide leukocyte DNA-methylation. METHODS: Methylation levels were assessed using Illumina 450k arrays on 9,894 individuals of European ancestry from 12 cohort studies. Linear-mixed-models were used to study the association of additive MTHFR 677C>T and genetic-risk score (GRS) based on 18 homocysteine-associated SNPs, with genome-wide methylation. RESULTS: Meta-analysis revealed that the MTHFR 677C>T variant was associated with 35 CpG sites in cis, and the GRS showed association with 113 CpG sites near the homocysteine-associated variants. Genome-wide analysis revealed that the MTHFR 677C>T variant was associated with 1 trans-CpG (nearest gene ZNF184), while the GRS model showed association with 5 significant trans-CpGs annotated to nearest genes PTF1A, MRPL55, CTDSP2, CRYM and FKBP5. CONCLUSIONS: Our results do not show widespread changes in DNA-methylation across the genome, and therefore do not support the hypothesis that mildly elevated homocysteine is associated with widespread methylation changes in leukocytes.


Assuntos
Metilação de DNA , Homocisteína/metabolismo , Leucócitos/metabolismo , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Adulto , Cromossomos Humanos Par 6 , Estudos de Coortes , Ilhas de CpG , Humanos , Polimorfismo de Nucleotídeo Único
3.
Epigenomics ; 9(11): 1403-1422, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28990796

RESUMO

AIM: Homocysteine (Hcy) is a sensitive marker of one-carbon metabolism. Higher Hcy levels have been associated with global DNA hypomethylation. We investigated the association between plasma Hcy and epigenome-wide DNA methylation in leukocytes. METHODS: Methylation was measured using Illumina 450 k arrays in 2035 individuals from six cohorts. Hcy-associated differentially methylated positions and regions were identified using meta-analysis. RESULTS: Three differentially methylated positions cg21607669 (SLC27A1), cg26382848 (AJUBA) and cg10701000 (KCNMA1) at chromosome 19, 14 and 10, respectively, were significantly associated with Hcy. In addition, we identified 68 Hcy-associated differentially methylated regions, the most significant of which was a 1.8-kb spanning domain (TNXB/ATF6B) at chromosome 6. CONCLUSION: We identified novel epigenetic loci associated with Hcy levels, of which specific role needs to be further validated.


Assuntos
Metilação de DNA , Epigênese Genética , Homocisteína/sangue , Leucócitos/metabolismo , Fator 6 Ativador da Transcrição , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Proteínas de Transporte de Ácido Graxo/genética , Proteínas de Transporte de Ácido Graxo/metabolismo , Feminino , Estudo de Associação Genômica Ampla , Humanos , Proteínas com Domínio LIM/genética , Proteínas com Domínio LIM/metabolismo , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/genética , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Masculino , Tenascina/genética , Tenascina/metabolismo
4.
Clin Biochem ; 50(18): 1030-1033, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28823760

RESUMO

INTRODUCTION: Vitamin B12 deficiency is mostly caused by insufficient gastro-intestinal absorption and in rare conditions by Transcobalamin (TC) deficiency. Unsaturated Transcobalamin (apoTC) can be measured by a binding assay using radiolabeled cobalamin. The Active B12 test analyzes saturated Transcobalamin (holoTC) and we hypothesize that this test can be used to measure total TC by additional in vitro saturation with cobalamin. METHODS: Serum was saturated in vitro (16 times dilution) with a cyanocobalamin solution and total TC was selectively measured with the Abbott Active B12 test. ApoTC was calculated by subtracting endogenous holoTC from total TC after correction for dilution. Linearity was determined with a pool serum dilution series. Precision was investigated according to the CLSI EP15 protocol. Method comparison was performed against a binding assay using radiolabeled cobalamin. Reference values were determined in 100 healthy controls. RESULTS: The method was linear in the range of 240 to 1933pmol/L (R2=0.997, lack of fit F=1.61). Precision of low- and high-pool total TC in serum were; 5.2% and 4.3% respectively. Method comparison against a radiolabeled cobalamin binding assay showed a proportional bias of 30% (y=0.70x+126). Total TC reference values were determined at 500-1276pmol/L. CONCLUSION: We describe a rapid method to quantify total TC, which can be implemented on routine platforms using commercial Active B12 tests. In addition, apoTC can be assessed by subtracting endogenous holoTC concentration which can be measured in the same run, securing the same calibration level for all three parameters (holoTC, apoTC and total TC). This method is applicable in clinical diagnostics and in larger epidemiological studies.


Assuntos
Transcobalaminas/análise , Bioensaio/métodos , Humanos , Países Baixos , Valores de Referência , Soro/metabolismo , Vitamina B 12/análise , Vitamina B 12/sangue , Deficiência de Vitamina B 12/sangue , Deficiência de Vitamina B 12/metabolismo
5.
Maturitas ; 97: 14-20, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28159055

RESUMO

OBJECTIVES: To design a frailty index (FI) and evaluate three methods to handle missing data. Furthermore, we evaluated its construct (i.e., skewed distribution, correlation with age and sub-maximum score) and criterion validity (based on mortality risk). STUDY DESIGN: We included 11,539 participants (45± years) from a population-based cohort in the Netherlands. Frailty was measured with a FI, which we constructed based on the accumulation of 45 health-related variables, related to mood, cognition, functional status, diseases and conditions, biomarkers, and nutritional status. A total FI-score was calculated by averaging the scores of the deficits, resulting in a score between 0 and 1, with higher scores indicating increasing frailty. Mean imputation, single- and multiple imputation were applied. MAIN OUTCOME MEASURE: Mortality data were obtained by notification from the municipal administration. Median follow-up time was 9.5 years, during which 3902 (34%) participants died. RESULTS: The median FI for the full population was 0.16 (IQR=0.11-0.23). The distribution of the FI was slightly right-skewed, the absolute maximum score was 0.78 and there was a strong correlation with age (Pearson correlation=0.52;95%CI=0.51-0.54). The adjusted HR per unit increase in FI-score on mortality was 1.05 (95%CI=1.05-1.06). Multiple imputation seemed to provide more robust results than mean imputation. CONCLUSION: Based on our results we advise to the use of at least 30 deficits from different health domains to construct a FI if data are not imputed. Future research should use the continuous nature of the FI to monitor trajectories in frailty and find preventive strategies.


Assuntos
Idoso Fragilizado , Avaliação Geriátrica/métodos , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade , Países Baixos
6.
J Proteome Res ; 16(1): 3-13, 2017 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-27769114

RESUMO

Lung cancer has the highest mortality rate among cancer patients in the world, in particular because most patients are only diagnosed at an advanced and noncurable stage. Computed tomography (CT) screening on high-risk individuals has shown that early detection could reduce the mortality rate. However, the still high false-positive rate of CT screening may harm healthy individuals because of unnecessary follow-up scans and invasive follow-up procedures. Alternatively, false-negative and indeterminate results may harm patients due to the delayed diagnosis and treatment of lung cancer. Noninvasive biomarkers, complementary to CT screening, could lower the false-positive and false-negative rate of CT screening at baseline and thereby reduce the number of patients that need follow-up and diagnose patients at an earlier stage of lung cancer. Lung cancer tissue generates lung cancer-associated proteins to which the immune system might produce high-affinity autoantibodies. This autoantibody response to tumor-associated antigens starts during early stage lung cancer and may endure over years. Identification of tumor-associated antigens or the corresponding autoantibodies in body fluids as potential noninvasive biomarkers could thus be an effective approach for early detection and monitoring of lung cancer. We provide an overview of differentially expressed protein, antigen, and autoantibody biomarkers that combined with CT imaging might be of clinical use for early detection of lung cancer.


Assuntos
Antígenos de Neoplasias/sangue , Autoanticorpos/sangue , Biomarcadores Tumorais/sangue , Detecção Precoce de Câncer/métodos , Neoplasias Pulmonares/sangue , Adenocarcinoma/sangue , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/genética , Adenocarcinoma/imunologia , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Autoanticorpos/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Carcinoma de Células Grandes/sangue , Carcinoma de Células Grandes/diagnóstico por imagem , Carcinoma de Células Grandes/genética , Carcinoma de Células Grandes/imunologia , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/imunologia , Expressão Gênica , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Carcinoma de Pequenas Células do Pulmão/sangue , Carcinoma de Pequenas Células do Pulmão/diagnóstico por imagem , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/imunologia , Tomografia Computadorizada por Raios X
7.
Drug Saf ; 40(3): 241-248, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27995520

RESUMO

INTRODUCTION: Gastric acid-related symptoms are highly prevalent in the general population (21-40%), and more than 11% of individuals use medication for the treatment of these symptoms. The uptake of micronutrients is dependent on the gastrointestinal potential of hydrogen (pH). OBJECTIVE: We hypothesized that medication affecting gastrointestinal pH reduces the availability of B vitamins, thereby deranging one-carbon metabolism and detrimentally affecting spermatogenesis. METHODS: This explorative nested case-control study in men of subfertile couples investigated associations between medication used for gastric acid-related symptoms and semen parameters. We included 40 men using medication for gastric acid-related symptoms and 843 men not using medication. Semen analyses were performed between 70 days before and 21 days after the visit. RESULTS: The use of medication was associated with a twofold higher risk of a low total motile sperm count [TMSC <1 × 106, odds ratio (OR) 2.090, p = 0.049] and negatively with sperm concentration (ß -0.320, p = 0.028). Red blood cell folate was positively associated with TMSC (ß 0.257, p = 0.026), sperm count (ß 1.679, p = 0.013) and ejaculate volume (ß 0.120, p = 0.023), and total homocysteine (tHcy) was negatively associated with sperm count (ß -0.077, p = 0.021). CONCLUSION: Here we delineate associations between the use of medication for gastric acid-related symptoms and poor semen quality in men of subfertile couples. The use of medication for gastric acid-related symptoms is associated with a twofold higher risk of a low TMSC and a decreased sperm concentration. Although these findings warrant further research on causality, the associations between folate, tHcy and semen quality emphasize the importance of preconception counselling in male subfertility.


Assuntos
Fármacos Gastrointestinais/efeitos adversos , Sêmen/efeitos dos fármacos , Motilidade Espermática/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Adulto , Estudos de Casos e Controles , Ácido Fólico/sangue , Ácido Gástrico , Fármacos Gastrointestinais/administração & dosagem , Humanos , Concentração de Íons de Hidrogênio , Infertilidade Masculina/etiologia , Masculino , Países Baixos , Análise do Sêmen , Contagem de Espermatozoides
8.
Paediatr Perinat Epidemiol ; 30(4): 386-96, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27271101

RESUMO

BACKGROUND: Suboptimal dietary intake during pregnancy may have long-term health implications in children. These effects may be mediated by fetal growth. We investigated the associations of early pregnancy and umbilical cord total homocysteine (tHcy), folate, and total and active vitamin B12 concentrations with fetal growth parameters repeatedly measured in pregnancy and at birth. METHODS: This study was performed in 5890 pregnant women, participating in a population-based prospective cohort study. Blood samples were obtained from women in early pregnancy and from the umbilical vein at delivery. Fetal size parameters were repeatedly measured by ultrasound. Information about birth anthropometrics was retrieved from medical records. RESULTS: High early pregnancy maternal tHcy (≥8.31 µmol/L), as compared with low maternal homocysteine (≤5.80 µmol/L), and low early pregnancy maternal folate (≤9.10 nmol/L), as compared with high maternal folate (≥25.81 nmol/L) concentrations, were associated with reduced weight growth patterns throughout pregnancy, resulting in birthweight differences of -102.3 g (95% CI -139.6, -65.0) and -113.0 g (95% CI -159.6, -66.3), respectively. Low umbilical cord folate concentrations (≤15.20 nmol/L) as compared with high umbilical cord folate concentrations (≥28.41 nmol/L) were also associated with a lower birthweight and birth length (P < 0.001). Interestingly, compared with higher umbilical cord vitamin B12 , lower vitamin B12 concentrations were associated with a higher weight, length, and head circumference at birth (P < 0.01). CONCLUSION: Early pregnancy maternal and umbilical cord markers of the homocysteine pathway are significantly associated with fetal growth patterns. These differences arise from mid-pregnancy onwards.


Assuntos
Sangue Fetal/metabolismo , Desenvolvimento Fetal , Homocisteína/sangue , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Adulto , Biomarcadores/sangue , Peso ao Nascer , Feminino , Ácido Fólico/sangue , Humanos , Recém-Nascido , Masculino , Fenômenos Fisiológicos da Nutrição Materna , Países Baixos/epidemiologia , Gravidez , Proteínas da Gravidez/sangue , Efeitos Tardios da Exposição Pré-Natal/sangue , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Estudos Prospectivos , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Vitamina B 12/sangue
9.
Am J Clin Pathol ; 145(3): 299-307, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27124911

RESUMO

OBJECTIVES: Counting cells in cerebrospinal fluid (CSF) using automated analyzers is generally problematic due to low precision at low cell numbers. To overcome this limitation, Sysmex (Kobe, Japan) developed the high-sensitive analysis (hsA) research mode specifically for counting cells in fluids that contain low cell counts. We evaluated this mode by counting RBCs, WBCs, and differentiated WBCs in CSF samples. METHODS: We analyzed 248 CSF samples using the hsA mode and compared these results with those obtained using the manual counting method. We also evaluated the linearity, detection limits, carryover, and precision of the hsA mode. RESULTS: Using the hsA mode, the lower limit of quantification for RBCs and WBCs was 10 and 2 cells/µL, respectively. Comparing the two methods revealed good agreement with respect to WBCs (y = 1.08x + 0.52), RBCs (y = 1.07x + 0.00), lymphocytes (y = 1.00x + 0.00), neutrophils (y = 1.05x + 0.00), and monocytes (y = 0.88x + 0.07). Regression analysis for samples containing low WBCs (<10 cells/µL) and low RBCs (<50 cells/µL) also had good agreement, although a slight positive bias was found for RBCs. Linearity was good (r(2) ≥ 0.99) for all parameters evaluated. Carryover was negligible and never exceeded 0.04%. CONCLUSIONS: The XN hsA research mode provides reliable cell counts in CSF samples, even in samples containing low numbers of WBCs and RBCs.


Assuntos
Líquido Cefalorraquidiano/citologia , Contagem de Eritrócitos/métodos , Contagem de Leucócitos/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Automação Laboratorial , Criança , Pré-Escolar , Contagem de Eritrócitos/instrumentação , Feminino , Humanos , Lactente , Contagem de Leucócitos/instrumentação , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
10.
Cancer Immunol Res ; 4(2): 165-72, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26659304

RESUMO

The high mortality rate in lung cancer is largely attributable to late diagnosis. Case-control studies suggest that autoantibodies to the survivin protein are potential biomarkers for early diagnosis. We tested the hypothesis that sandwich ELISA can detect autoantibodies to survivin before radiologic diagnosis in patients with early-stage non-small cell lung cancer (NSCLC). Because previous studies assayed survivin autoantibodies with the direct antigen-coating ELISA (DAC-ELISA), we first compared that assay with the sandwich ELISA. Based on the more robust results from the sandwich ELISA, we used it to measure survivin autoantibodies in the serum of 100 individuals from a well-controlled population study [the Dutch-Belgian Lung Cancer Screening Trial (NELSON) trial] composed of current and former smokers (50 patients with NSCLC, both before and after diagnosis, and 50 matched, smoking-habit control subjects), and another 50 healthy nonsmoking control subjects. We found no difference in specific autoantibodies to survivin in NSCLC patients, although nonspecific median optical densities were 24% higher (P < 0.001) in both NSCLC patients and smokers, than in healthy nonsmokers. Finally, we confirmed the ELISA results with Western blot analysis of recombinant and endogenous survivin (HEK-293), which showed no anti-survivin reactivity in patient sera. We conclude that specific anti-survivin autoantibody reactivity is most likely not present in sera before or after diagnosis. Autoantibody studies benefit from a comparison to a well-controlled population, stratified for smoking habit.


Assuntos
Especificidade de Anticorpos , Autoanticorpos/imunologia , Proteínas Inibidoras de Apoptose/imunologia , Neoplasias Pulmonares/imunologia , Fumar , Idoso , Autoanticorpos/sangue , Biomarcadores Tumorais , Ensaio de Imunoadsorção Enzimática , Feminino , Células HEK293 , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Survivina
12.
Eur J Clin Invest ; 45(8): 833-41, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26094490

RESUMO

BACKGROUND: The investigation of the human follicle fluid proteome has gained much interest in the search of new markers as predictors for in vitro fertilization and intracytoplasmic sperm injection (IVF/ICSI) treatment outcome. Follicular fluid folate, as substrate of one carbon (1-C) metabolism, affects follicular metabolism and oocyte and embryo quality. From this background, we aim to identify a folate-related follicle fluid proteome that associates with IVF/ICSI treatment outcome. METHODS: In a nested case-control study embedded in a periconception cohort, we performed qualitative and quantitative proteomic analyses using nanoflow LC-MS/MS and TMT labelling in 30 monofollicular fluid samples from women undergoing IVF/ICSI treatment of which 15 used and 15 did not use a folic acid supplement. The protein data are analysed using scaffold proteome Software and differential abundances are expressed as Log2-fold change. Blood samples were obtained before and after treatment for determination of biomarkers of 1-C metabolism and estradiol. RESULTS: We identified 227 uniquely expressed proteins in follicular fluid. In folic acid supplement users compared to nonusers, we established a lower abundance of C-reactive protein (-2.03; P = < 0.01) and higher abundances of apolipoproteins from high-density lipoprotein (HDL), most notably A-I (+1.28; P = < 0.01) and C-I (+1.11; P = 0.016). CONCLUSION: Preconception folic acid supplement use is associated with suppression of the inflammatory pathway and upregulation of the HDL pathway in human follicular fluid, being a preferential source of cholesterol for steroid hormone synthesis. Studies are needed on the tissue specificity and on the beneficial effects of embryo quality and IVF/ICSI treatment outcome of the proteome of these pathways.


Assuntos
Fertilização In Vitro , Ácido Fólico/uso terapêutico , Líquido Folicular/metabolismo , Cuidado Pré-Concepcional/métodos , Proteoma/metabolismo , Injeções de Esperma Intracitoplásmicas , Complexo Vitamínico B/uso terapêutico , Adulto , Apolipoproteínas/metabolismo , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Proteína de Ligação ao Complemento C4b/metabolismo , Regulação para Baixo , Feminino , Regulação da Expressão Gênica , Geraniltranstransferase/metabolismo , Humanos , Proteína Acessória do Receptor de Interleucina-1/metabolismo , Calicreínas/metabolismo , Folículo Ovariano , Estudos Prospectivos , Proteínas/metabolismo , Receptores de IgG/metabolismo , Regulação para Cima
13.
Clin Chem Lab Med ; 53(11): 1689-706, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25879321

RESUMO

In many inflammatory diseases, the cellular components in body fluids [cerebrospinal fluid (CSF), serous fluids] are increased, rendering essential diagnostic information. The diagnostic value of the total white blood cell count (WBC) and differential count has been evaluated extensively over the years, and a remarkable amount of knowledge has been gained; yet, there is a great deal of clinical uncertainty whether the diagnosis should be based solely on these variables. In some diseases, such as peritonitis, the total WBC and differential count has high sensitivity; whereas, in differentiating pleural effusions, it lacks the sensitivity required to be clinically useful. Nevertheless, many guidelines consider these tests as cornerstone parameters, and in combination with clinical variables, they can successfully guide clinical decision making in initiating or postponing a treatment course for infection and/or inflammatory diseases while awaiting culture results. Although other methods are available for detecting and differentiating WBCs in body fluids, manual microscopy is still considered the gold standard despite its many limitations. During the last decade, automated analyzers have become a popular method for first line screening. Continued progress in their design has led to major improvements including their speed, improved accuracy and lower variability compared with microscopy. Disadvantages of this method include high imprecision in low ranges (depending on the method) and interfering factors. In a time where automation is at the front line in clinical laboratories, it is essential the results obtained are precise, accurate and reproducible. This review provides an overview of the relevance for cell counting in a variety of diagnostic body fluids, and highlights the current technologies used.


Assuntos
Líquidos Corporais/citologia , Citometria de Fluxo , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/diagnóstico , Leucócitos/patologia , Serviços de Laboratório Clínico , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Contagem de Leucócitos
14.
Ann Rheum Dis ; 74(2): 408-14, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24297383

RESUMO

OBJECTIVE: To investigate if erythrocyte-methotrexate-polyglutamate (MTX-PG) concentrations in patients with rheumatoid arthritis (RA) are associated with disease activity or adverse events. METHODS: We used a longitudinal study design with two cohorts. The derivation cohort included 102 and the validation cohort included 285 patients with RA on MTX. We measured erythrocyte-MTX-PG with 1-5 glutamate residues at 3 months, 6 months and 9 months after MTX start with a liquid chromatography (LC)-mass spectrometry (MS)/MS assay. Outcomes were disease activity score in 28 joints (DAS28) and adverse events. Longitudinal associations of MTX-PG concentrations after 3 months, 6 months and 9 months with DAS28 were tested with a linear mixed model adjusted for age, gender, baseline DAS28, MTX dose and comedication. RESULTS: In the derivation cohort, mean DAS28 decreased from 4.26 (SE=0.14) at baseline to 2.72 (SE=0.13) after 9 months. Thirty per cent of patients in the derivation cohort experienced more than three adverse events after 3 months, which decreased to 18% after 9 months. In the validation cohort, DAS28 and adverse events were comparable with the derivation cohort. In the derivation cohort, MTX-PG1 (ß=-0.005), MTX-PG2 (ß=-0.022), MTX-PG3 (ß=-0.007) and total MTX-PG (ß=-0.004) were associated (p<0.05) with lower DAS28 over 9 months. In the validation cohort, MTX-PG2 (ß=-0.015), MTX-PG3 (ß=-0.010), MTX-PG4 (ß=-0.008) and total MTX-PG (ß=-0.003) were associated with lower DAS28 over 9 months. None of the MTX-PGs was associated with adverse events. CONCLUSIONS: In this first longitudinal study, we showed that an increase in erythrocyte-MTX-PG concentration was associated with a decreased DAS28 over 9 months in two cohorts, and is therefore a potential tool for therapeutic drug monitoring of MTX in RA.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Eritrócitos/química , Metotrexato/análogos & derivados , Metotrexato/uso terapêutico , Ácido Poliglutâmico/análogos & derivados , Cromatografia Líquida , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Metotrexato/análise , Pessoa de Meia-Idade , Ácido Poliglutâmico/análise , Espectrometria de Massas em Tandem
15.
Front Psychol ; 5: 1418, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25538666

RESUMO

"How social norms change" is not only a theoretical question but also an empirical one. Many organizations have implemented programs to abandon harmful social norms. These programs are standardly monitored and evaluated with a set of empirical tools. While monitoring and evaluation (M&E) of changes in objective outcomes and behaviors is well-developed, we will argue that M&E of changes in the wide range of beliefs and preferences important to social norms is still problematic. In this paper, we first present a theoretical framework and then show how it should guide social norms measurement. As a case study, we focus on the harmful practice of child marriage. We show how an operational theory of social norms can guide the design of surveys, experiments, and vignettes. We use examples from existing research to illustrate how to study social norms change.

16.
Clin Chem Lab Med ; 52(12): 1781-90, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24964259

RESUMO

BACKGROUND: We evaluated the new body fluid mode on the UF-1000i urinalysis analyzer for counting total white blood cells (WBC) and red blood cells (RBC) in continuous ambulatory peritoneal dialysis (CAPD), ascites and pleural fluids. METHODS: We collected 154 body fluid samples, and compared the results of the UF-1000i BF mode with the Fuchs-Rosenthal counting chamber and the XN-1000 BF mode. Linearity, carry over and precision were also assessed. RESULTS: Method comparison results showed acceptable WBC agreement between UF-1000i and chamber (y=1.27x+3.13, n=135, r=0.99) and between UF-1000i and XN (y=1.15x+0.31, n=135, r=1.00). Comparison between the UF-1000i and both comparison methods showed good agreement for RBC counts. Overall results were better when UF-1000i was compared with the XN-1000 than with the Fuchs-Rosenthal chamber. The lower limit of quantitation was defined at 9×106 WBC/L and at 25×106 RBC/L. Linearity for both WBC (r=1.00) and RBC (r=0.99) was good. Carry over was negligible, and it never exceeded 0.01%. In one sample, a high discrepancy was observed between WBC results for both automated analyzers and the counting chamber. This discrepancy was due to interfering factors, such as bacteria and yeast cells, and it led to a false increased WBC count on both automated systems. CONCLUSIONS: The UF-1000i BF mode offers rapid and reliable total WBC and RBC counts for initial screening of CAPD, ascites and pleural fluid, and can improve the workflow in a routine laboratory; however, when using automated analyzers, the inspection of scattergrams is required to ensure the most accurate results are obtained.


Assuntos
Líquidos Corporais/citologia , Citometria de Fluxo/métodos , Automação , Contagem de Eritrócitos , Citometria de Fluxo/instrumentação , Humanos , Contagem de Leucócitos , Análise de Regressão , Reprodutibilidade dos Testes , Urinálise
17.
Arthritis Rheumatol ; 66(8): 2026-36, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24692301

RESUMO

OBJECTIVE: To investigate whether methotrexate (MTX) use, as compared to other therapies, and erythrocyte methotrexate polyglutamate (MTXGlu) concentrations are associated with changes in glycosylated hemoglobin (HbA1c ) levels in rheumatoid arthritis (RA) patients. METHODS: The derivation cohort consisted of patients selected from the Treatment in the Rotterdam Early Arthritis Cohort who fulfilled the 2010 American College of Rheumatology/European League Against Rheumatism classification criteria for RA. Patients were randomized to 6 treatment arms: triple disease-modifying antirheumatic drug (DMARD) therapy (consisting of MTX, sulfasalazine, and hydroxychloroquine [HCQ]) + intramuscular (IM) glucocorticoids, triple DMARD therapy + oral glucocorticoids, MTX + oral glucocorticoid therapy, MTX therapy, oral glucocorticoid therapy, and HCQ therapy. HbA1c levels were determined at baseline and at 3 months. Concentrations of erythrocyte MTXGlu1-5 were measured after 3 months of treatment. Within treatment arms, changes in the level of HbA1c were compared by paired t-test. Associations of MTXGlu concentrations with changes in the level of HbA1c were tested using multiple linear regression analysis, adjusted for age, sex, body mass index, and comedication. Significant associations were validated using data on RA patients taking MTX who were enrolled in the Methotrexate in Rotterdam cohort. RESULTS: In the derivation cohort, the mean change in HbA1c level after 3 months of treatment was -1.9 mmoles/mole (-0.18%) (P = 0.001). Levels of HbA1c decreased in 4 of the individual treatment groups, as follows: for the triple DMARD therapy + IM glucocorticoids treatment arm, -5.5 mmoles/mole (-0.50%) (P < 0.001), for the triple DMARD therapy + oral glucocorticoids treatment arm, -3.7 mmoles/mole (-0.34%) (P < 0.001), for the MTX treatment arm, -0.8 mmoles/mole (-0.08%) (P = 0.018), and for the HCQ treatment arm, -2.0 mmoles/mole (-0.19%) (P = 0.175). Increased levels of MTXGlu2 (ß = -0.20, P = 0.005), MTXGlu3 (ß = -0.31, P < 0.001), MTXGlu4 (ß = -0.33, P < 0.001) after treatment, MTXGlu5 (ß = -0.39, P < 0.001), and total MTXGlu (ß = -0.29, P < 0.001) were associated with decreased levels of HBA1c . In the validation cohort, levels of HbA1c were decreased by 2.6 mmoles/mole (0.23%) (P < 0.001) after treatment, and MTXGlu3 was associated with decreased levels of HbA1c (ß = -0.26, P = 0.018). CONCLUSION: MTX use and higher concentrations of erythrocyte MTXGlu are associated with decreased levels of HbA1c in RA patients. Triple DMARD therapy and HCQ treatment resulted in reduced HbA1c levels, and glucocorticoid treatment resulted in increased levels of HbA1c .


Assuntos
Antirreumáticos/farmacologia , Antirreumáticos/uso terapêutico , Artrite Reumatoide/sangue , Artrite Reumatoide/tratamento farmacológico , Eritrócitos/química , Hemoglobina A Glicada/efeitos dos fármacos , Metotrexato/análogos & derivados , Metotrexato/farmacologia , Metotrexato/uso terapêutico , Ácido Poliglutâmico/análogos & derivados , Feminino , Humanos , Masculino , Metotrexato/análise , Pessoa de Meia-Idade , Ácido Poliglutâmico/análise , Estudos Prospectivos
18.
Am J Med Genet A ; 161A(10): 2545-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24038802

RESUMO

Nonsyndromic cleft lip with or without cleft palate (NSCL/P), the most common type of orofacial clefting, is one of the most frequent congenital defects. Based on epidemiological data, NSCL/P can be distinguished from nonsyndromic cleft palate only (NSCPO). Both phenotypes have a complex etiology and environmental and genetic factors are involved in their development. To date, genome-wide association studies have identified 12 genetic factors that increase the risk for NSCL/P in Europeans. Six of them have been independently replicated in samples derived from the same population. The aim of the present study was to replicate the remaining six NSCL/P risk loci in chromosomal regions 1p22.1, 1p36, 3p11.1, 8q21.3, 15q22.2, and 20q12 in a family-based sample of European descent. Each of the top-associated SNPs (single nucleotide polymorphisms) was genotyped in 343 NSCL/P and 266 NSCPO nuclear trios. Single-marker association analysis in the NSCL/P sample showed a significant association with SNP rs742071 (1p36, Pcorrected = 3.74 × 10(-3) ), which is located in the intronic region of PAX7, a gene known to be functionally implicated in craniofacial development. Two additional loci, 1p22.1 and 20q12, were nominally significant, but did not withstand correction for multiple testing. There was no evidence that the NSCL/P risk alleles contribute to the etiology of NSCPO, further supporting that these two subtypes of orofacial clefting are primarily etiologically distinct.


Assuntos
Fenda Labial/complicações , Fenda Labial/genética , Fissura Palatina/complicações , Fissura Palatina/genética , Grupo com Ancestrais do Continente Europeu/genética , Predisposição Genética para Doença , Locos de Características Quantitativas , Alelos , Estudos de Associação Genética , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Risco
19.
Am J Clin Nutr ; 98(3): 668-76, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23824729

RESUMO

BACKGROUND: The strong observational association between total homocysteine (tHcy) concentrations and risk of coronary artery disease (CAD) and the null associations in the homocysteine-lowering trials have prompted the need to identify genetic variants associated with homocysteine concentrations and risk of CAD. OBJECTIVE: We tested whether common genetic polymorphisms associated with variation in tHcy are also associated with CAD. DESIGN: We conducted a meta-analysis of genome-wide association studies (GWAS) on tHcy concentrations in 44,147 individuals of European descent. Polymorphisms associated with tHcy (P < 10(⁻8) were tested for association with CAD in 31,400 cases and 92,927 controls. RESULTS: Common variants at 13 loci, explaining 5.9% of the variation in tHcy, were associated with tHcy concentrations, including 6 novel loci in or near MMACHC (2.1 × 10⁻9), SLC17A3 (1.0 × 10⁻8), GTPB10 (1.7 × 10⁻8), CUBN (7.5 × 10⁻¹°), HNF1A (1.2 × 10⁻¹²)), and FUT2 (6.6 × 10⁻9), and variants previously reported at or near the MTHFR, MTR, CPS1, MUT, NOX4, DPEP1, and CBS genes. Individuals within the highest 10% of the genotype risk score (GRS) had 3-µmol/L higher mean tHcy concentrations than did those within the lowest 10% of the GRS (P = 1 × 10⁻³6). The GRS was not associated with risk of CAD (OR: 1.01; 95% CI: 0.98, 1.04; P = 0.49). CONCLUSIONS: We identified several novel loci that influence plasma tHcy concentrations. Overall, common genetic variants that influence plasma tHcy concentrations are not associated with risk of CAD in white populations, which further refutes the causal relevance of moderately elevated tHcy concentrations and tHcy-related pathways for CAD.


Assuntos
Doença da Artéria Coronariana/genética , Genes , Loci Gênicos , Genótipo , Homocisteína/genética , Polimorfismo Genético , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/etiologia , Predisposição Genética para Doença , Homocisteína/sangue , Humanos , Fatores de Risco
20.
Am J Obstet Gynecol ; 209(2): 121.e1-11, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23583216

RESUMO

OBJECTIVE: Fetal growth is dependent on adequate development of the placenta. Impaired angiogenesis and vasculogenesis in early pregnancy compromises placental and embryonic development. The proteins soluble fms-like tyrosine kinase (sFlt)-1, placental growth factor (PlGF), and plasminogen activator inhibitor (PAI)-2, and the B vitamin folate are determinants of placental development. This study aims to identify associations between these maternal biomarkers and early fetal size. STUDY DESIGN: From a prospective birth cohort study in The Netherlands, 1491 pregnant women were selected for this study. At a mean gestational age (GA) of 12.4 weeks (SD 0.8) maternal venous blood samples were obtained to determine the concentrations of sFlt-1, PlGF, PAI-2, and folate. Early fetal size was assessed with measurement of the crown-to-rump length (CRL) at a mean of 12.4 weeks' GA (SD 0.8). Analyses were performed using multivariable linear regression analyses with the biomarkers (continuous, quintiles) as regressors and CRL as main outcome measure. RESULTS: Linear trend analysis showed positive associations between maternal sFlt-1 (P < .001), PlGF (P = .042), PAI-2 (P < .001), and folate (P = .039) and CRL. These associations were independent of GA, maternal age, height, body mass index, ethnicity, fetal sex, parity, educational level, smoking, and folic acid supplement use (folate not adjusted). CONCLUSION: sFlt-1, PlGF, PAI-2, and folate are positively associated with first-trimester fetal size.


Assuntos
Desenvolvimento Fetal , Ácido Fólico/sangue , Inibidor 2 de Ativador de Plasminogênio/sangue , Proteínas da Gravidez/sangue , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Adulto , Estudos de Coortes , Feminino , Humanos , Fator de Crescimento Placentário , Placentação , Gravidez , Primeiro Trimestre da Gravidez , Estudos Prospectivos
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