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1.
N Z Med J ; 133(1523): 16-28, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-33032300

RESUMO

AIMS: To determine whether glycated haemoglobin (HbA1c) results from three commonly used platforms can be interpreted cumulatively and used interchangeably in individuals with common haemoglobinopathies. A secondary goal was to assess the relationship between HbA1c concentrations, and haemoglobin and mean corpuscular volume in this population. METHODS: One hundred and forty-five samples, mostly with haemoglobinopathies, were tested by each of: Roche Gen.3 Cobas c513, Capillarys 2 Flex-Piercing and Bio-Rad D-100 platforms. Statistical comparisons and limits of performance based on biological variation, international recommendations, and local diagnostic cut-offs were drawn upon to determine comparability of results. RESULTS: Inter-platform measurements were not significantly different for the large majority of results. The four HbA1c results that showed maximum discrepancy between triplicates had the following abnormalities: heterozygous haemoglobin S/ beta thalassemia, heterozygous haemoglobin S/ alpha thalassemia, beta thalassemia trait and alpha thalassemia trait. Six triplicates of results in the thalassemia groups (7.5% of thalassemia samples) had levels that misclassified patients' glycaemic status. There was no correlation between HbA1c concentration and mean corpuscular volume, and a weak negative correlation between HbA1c concentration and haemoglobin concentration. CONCLUSION: HbA1c concentrations measured by Cobas c513, Capillarys 2 Flex-Piercing and the Bio-Rad D-100 were found to be comparable in the large majority of samples. While discordance was due to assay imprecision in some cases, in others no biological or analytical explanation could be found.


Assuntos
Análise Química do Sangue/métodos , Análise Química do Sangue/normas , Hemoglobina A Glicada/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hemoglobinopatias/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Adulto Jovem
2.
Ann Biol Clin (Paris) ; 78(5): 555-564, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33026350

RESUMO

Biochemical diagnosis of hereditary metabolic diseases requires the detection and simultaneous identification of a large number of compounds, hence the interest in metabolic profiles. Amino acid chromatography allows the identification and quantification of more than forty compounds. As part of the accreditation process for medical biology examinations according to standard NF EN ISO 15189, the group from SFEIM recommends an approach to accredit amino acid chromatography. Validation parameters and recommendations are discussed in this specific framework.


Assuntos
Aminoácidos/análise , Cromatografia/normas , Testes Diagnósticos de Rotina/normas , Erros Inatos do Metabolismo/diagnóstico , Acreditação/normas , Adulto , Aminoácidos/sangue , Aminoácidos/líquido cefalorraquidiano , Aminoácidos/urina , Amniocentese/normas , Líquido Amniótico/química , Análise Química do Sangue/métodos , Análise Química do Sangue/normas , Coleta de Amostras Sanguíneas/normas , Criança , Cromatografia/métodos , Cromatografia Líquida/normas , Testes Diagnósticos de Rotina/métodos , Feminino , Humanos , Recém-Nascido , Erros Inatos do Metabolismo/sangue , Erros Inatos do Metabolismo/líquido cefalorraquidiano , Erros Inatos do Metabolismo/urina , Triagem Neonatal/métodos , Triagem Neonatal/normas , Fase Pré-Analítica , Gravidez , Diagnóstico Pré-Natal/métodos , Diagnóstico Pré-Natal/normas , Espectrometria de Massas em Tandem/normas , Urinálise/métodos , Urinálise/normas , Coleta de Urina/normas
3.
Medicine (Baltimore) ; 99(36): e22048, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32899065

RESUMO

Owing to hormonal changes, women experience various psychophysiological alterations over a wide age range, which may result in decreased quality of life as well as in increased risks of diseases, such as cardiovascular diseases. Although studies have been performed to research complementary methods, such as meditation, the research field still requires an adequate amount of studies for public health guidelines. This pilot cross-sectional study aims to investigate a potential association of meditation with menopausal symptoms and blood chemistry for healthy women. In this study, data of 65 healthy women (age range 25-67) including 33 meditation practitioners and 32 meditation-naïve controls were analyzed to compare the Menopausal Rating Scale scores and blood chemistry with 7 more dropouts in the blood chemistry. For blood chemistry, nine components including glucose (GLU) and high-density lipoprotein cholesterol (HDL) were measured. Two-way analysis of variance was performed by dividing the total participants into 2 groups: premenopausal and postmenopausal participants. Compared to the control group, the meditation group showed a trend of reductions in the Menopausal Rating Scale total score (P = .054) and its 2 subcomponents: depressive mood (P = .064) and irritability (P = .061). In HDL level, there was a significant interaction between group and menopausal state (P = .039) with following post hoc results: among the premenopausal participants, a significant increase in the meditation group compared to the control group (P = .005); among the control group, a significant increase in the postmenopausal compared to the premenopausal participants (P = .030). In GLU level, there was a mild interaction between group and menopausal state (P = .070) with following post hoc results: among the postmenopausal participants, a trend of increase in the control group compared to the meditation group (P = .081); among the control group, a significant increase in the postmenopausal compared to the premenopausal participants (P = .040). Our research suggests a potential association of practicing meditation with alleviations in menopausal symptoms and changes in blood chemistry, warranting further studies with a longitudinal study design and larger populations to understand the underlying causal relationships.


Assuntos
Análise Química do Sangue/métodos , Meditação/métodos , Menopausa/sangue , Menopausa/psicologia , Adulto , Glicemia , Estudos de Casos e Controles , HDL-Colesterol/sangue , Estudos Transversais , Feminino , Voluntários Saudáveis , Humanos , Menopausa/fisiologia , Pessoa de Meia-Idade , Pós-Menopausa/sangue , Pós-Menopausa/psicologia , Pré-Menopausa/sangue , Pré-Menopausa/psicologia , Qualidade de Vida
4.
Ann Biol Clin (Paris) ; 78(5): 537-546, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32933890

RESUMO

Biochemical diagnosis of hereditary metabolic diseases requires the detection and simultaneous identification of a large number of compounds, hence the interest in metabolic profiles. Acylcarnitine profile allows the identification and quantification of more than thirty compounds. As part of the accreditation process for medical biology examinations according to standard NF EN ISO 15189, the group from SFEIM recommends an approach to accredit acylcarnitine profile. Validation parameters and recommendations are discussed in this specific framework.


Assuntos
Carnitina/análogos & derivados , Serviços de Laboratório Clínico/normas , Testes Diagnósticos de Rotina/normas , Erros Inatos do Metabolismo/diagnóstico , Acreditação , Adulto , Amniocentese/métodos , Amniocentese/normas , Líquido Amniótico/química , Análise Química do Sangue/métodos , Análise Química do Sangue/normas , Coleta de Amostras Sanguíneas/métodos , Coleta de Amostras Sanguíneas/normas , Carnitina/análise , Carnitina/sangue , Carnitina/urina , Criança , Cromatografia em Papel/normas , Feminino , Humanos , Recém-Nascido , Masculino , Erros Inatos do Metabolismo/sangue , Erros Inatos do Metabolismo/urina , Triagem Neonatal/métodos , Triagem Neonatal/normas , Fase Pré-Analítica/métodos , Fase Pré-Analítica/normas , Gravidez , Diagnóstico Pré-Natal/métodos , Diagnóstico Pré-Natal/normas , Urinálise/métodos , Urinálise/normas , Coleta de Urina/métodos , Coleta de Urina/normas
5.
PLoS One ; 15(8): e0237579, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32810196

RESUMO

OBJECTIVE: Patients with CAD have substantial residual risk of mortality, and whether hitherto unknown small-molecule metabolites and metabolic pathways contribute to this risk is unclear. We sought to determine the predictive value of plasma metabolomic profiling in patients with CAD. APPROACH AND RESULTS: Untargeted high-resolution plasma metabolomic profiling of subjects undergoing coronary angiography was performed using liquid chromatography/mass spectrometry. Metabolic features and pathways associated with mortality were identified in 454 subjects using metabolome-wide association studies and Mummichog, respectively, and validated in 322 subjects. A metabolomic risk score comprising of log-transformed HR estimates of metabolites that associated with mortality and passed LASSO regression was created and its performance validated. In 776 subjects (66.8 years, 64% male, 17% Black), 433 and 357 features associated with mortality (FDR-adjusted q<0.20); and clustered into 21 and 9 metabolic pathways in first and second cohorts, respectively. Six pathways (urea cycle/amino group, tryptophan, aspartate/asparagine, lysine, tyrosine, and carnitine shuttle) were common. A metabolomic risk score comprising of 7 metabolites independently predicted mortality in the second cohort (HR per 1-unit increase 2.14, 95%CI 1.62, 2.83). Adding the score to a model of clinical predictors improved risk discrimination (delta C-statistic 0.039, 95%CI -0.006, 0.086; and Integrated Discrimination Index 0.084, 95%CI 0.030, 0.151) and reclassification (continuous Net Reclassification Index 23.3%, 95%CI 7.9%, 38.2%). CONCLUSIONS: Differential regulation of six metabolic pathways involved in myocardial energetics and systemic inflammation is independently associated with mortality in patients with CAD. A novel risk score consisting of representative metabolites is highly predictive of mortality.


Assuntos
Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/mortalidade , Metaboloma/fisiologia , Metabolômica/métodos , Idoso , Biomarcadores/sangue , Biomarcadores/metabolismo , Análise Química do Sangue/métodos , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Redes e Vias Metabólicas , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Medição de Risco
6.
Nat Commun ; 11(1): 3903, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32764543

RESUMO

Top-down mass spectrometry (MS)-based proteomics provides a comprehensive analysis of proteoforms to achieve a proteome-wide understanding of protein functions. However, the MS detection of low-abundance proteins from blood remains an unsolved challenge due to the extraordinary dynamic range of the blood proteome. Here, we develop an integrated nanoproteomics method coupling peptide-functionalized superparamagnetic nanoparticles (NPs) with top-down MS for the enrichment and comprehensive analysis of cardiac troponin I (cTnI), a gold-standard cardiac biomarker, directly from serum. These NPs enable the sensitive enrichment of cTnI (<1 ng/mL) with high specificity and reproducibility, while simultaneously depleting highly abundant proteins such as human serum albumin (>1010 more abundant than cTnI). We demonstrate that top-down nanoproteomics can provide high-resolution proteoform-resolved molecular fingerprints of diverse cTnI proteoforms to establish proteoform-pathophysiology relationships. This scalable and reproducible antibody-free strategy can generally enable the proteoform-resolved analysis of low-abundance proteins directly from serum to reveal previously unachievable molecular details.


Assuntos
Análise Química do Sangue/métodos , Proteínas Sanguíneas/análise , Espectrometria de Massas/métodos , Proteômica/métodos , Troponina I/sangue , Biomarcadores/sangue , Humanos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestrutura , Nanotecnologia , Processamento de Proteína Pós-Traducional , Proteoma/análise , Reprodutibilidade dos Testes , Albumina Sérica Humana/análise
7.
Ann Biol Clin (Paris) ; 78(4): 417-424, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32753366

RESUMO

We present the case of a four-year-old girl, who was hospitalized in intensive care unit for a coma resulting from metabolic acidosis with increased anion gap. The patient was treated for short bowel syndrome, following necrotising enterocolitis, which occurred 51 days after birth. In our initial evaluation of the patient's metabolic acidosis, we were unable to identify the cause of the increased anion gap. Urinary organic acids chromatography identified a large peak of lactate (quantified at 15 mmol/mol of creatiniuria), as well as its metabolites. The discrepancy between normal blood lactate concentration assayed by enzymatic assay, and the large amount of lactate found by gas-chromatography/mass spectrometry (GC/MS) in urine highlights the limit of the stereospecificity of enzymatic assays. Indeed, most lactates assay use enzymatic assays that are specific for L-lactate, whereas organic acids chromatography, whose column is mostly achiral, can detect both stereoisomers, D- and L-lactate. Organic acids in urine analysis, in addition to the clinical context, suggested a diagnosis of D-lactic acidosis. Following a review of the physiopathology and treatment of short bowel syndrome, we will discuss the mechanism and diagnosis of the D-lactic acidosis in our patient. This case highlights the need to perform an organic acid profile in urine in the presence of any unexplained increased anion gap to determine its cause.


Assuntos
Equilíbrio Ácido-Base/fisiologia , Acidose Láctica/diagnóstico , Acidose/diagnóstico , Coma/diagnóstico , Síndrome do Intestino Curto/diagnóstico , Acidose/etiologia , Acidose/metabolismo , Acidose Láctica/etiologia , Acidose Láctica/metabolismo , Acidose Láctica/urina , Análise Química do Sangue/métodos , Pré-Escolar , Coma/sangue , Coma/etiologia , Coma/urina , Diagnóstico Diferencial , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Ácido Láctico/sangue , Ácido Láctico/urina , Síndrome do Intestino Curto/complicações , Síndrome do Intestino Curto/metabolismo , Urinálise
8.
Ann Biol Clin (Paris) ; 78(4): 454-460, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32616472

RESUMO

Blood angiotensin-converting enzyme (ACE) assay is now realized by the determination of enzyme activity on synthetic substrate, mostly furylacryloyl-phenylalanyl-L-glycyl-L-glycine (FAPGG). The matrix can be serum or heparin-plasma, with or without a separator; the assay developed on serum or plasma is not adapted to other matrix such as cerebrospinal fluid where the ACE activity is much lower. This assay has been adapted on a number of automated biochemistry analyzers with the specifications of the supplier of reagents, sometimes with modification of volumes or times for analysis. Samples can be stored at +4̊C for at least for one week, freezing at -20̊C is possible but refreezing is not advised. The assay is linear from 10 to 200 UI/L. Fidelity is excellent after calibration of the assay. Accuracy can be calculated from IQA and EQA results, and the analytical uncertainty is between 2% and 5% in function of the serum ACE value. Usual values will be soon available from studies on age brackets and sex, because ACE activity seems to be more elevated in boys during adolescence. At signature, it is interesting to have medical information on the diagnosis of sarcoidosis or its treatment including ACE inhibitors as a proof of intake; we can give a commentary on elevation of serum ACE activity from other causes than sarcoidosis and the causes for low activities.


Assuntos
Análise Química do Sangue/métodos , Peptidil Dipeptidase A/análise , Peptidil Dipeptidase A/sangue , Biomarcadores/análise , Biomarcadores/sangue , Análise Química do Sangue/normas , Coleta de Amostras Sanguíneas/métodos , Coleta de Amostras Sanguíneas/normas , Granuloma/sangue , Granuloma/diagnóstico , Granuloma/terapia , Humanos , Monitorização Fisiológica/métodos , Monitorização Fisiológica/normas , Fase Pré-Analítica , Reprodutibilidade dos Testes , Sarcoidose/sangue , Sarcoidose/diagnóstico , Sarcoidose/terapia , Sensibilidade e Especificidade , Estudos de Validação como Assunto
9.
Prostate ; 80(12): 1038-1042, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32506642

RESUMO

BACKGROUND: One of the principle limitations for more precise management of advanced prostate cancer is the lack of accurate biomarkers allowing estimation of tumor burden, ongoing assessment of progression, and response to treatment. Although prostate-specific antigen (PSA) performs modestly, nonsecreting cancers including those with early castrate-resistance warrant investigation of other predictive biomarkers. The objectives of these studies were to develop and perform initial validation of a circulating tumor DNA (ctDNA) methylation assay. METHODS: Methylation DETection of Circulating Tumor DNA (mDETECT) is a highly multiplexed targeted sequencing DNA methylation-based ctDNA blood test that captures the vast majority of prostate cancer phenotypes due to a careful development process that ensures that each probe region is methylated in at least 50% of all methylation-based subtypes and is not methylated in normal tissues. Next-generation sequencing of targeted polymerase chain reaction (PCR) products whose amplification is biased towards methylated DNA ensures the specificity of the assay by identifying multiple tumor-specific methylated CpG residues in each read. RESULTS: The final test is comprised of 46 PCR probes to 40 regions. It is relatively resistant to contaminating normal DNA and as a result functions in both serum and plasma samples. The assay was initially validated in a variety of prostate cancer cell lines to ensure specificity. Using a small number of longitudinal samples from prostate cancer patients initiating androgen deprivation therapy, the ability of mDETECT to track tumor burden was assessed compared with PSA. The mDETECT test signal generally paralleled that of PSA increasing and decreasing commensurate with tumor evolution in these patients. In two cases it appeared to anticipate clinical progression by a number of months compared to PSA and in a PSA nonproducing case, it was able to track tumor progression. CONCLUSIONS: mDETECT offers a promising tool for the assessment of prostate cancer burden based on the sensitive detection of prostate-specific ctDNA and requires further validation.


Assuntos
DNA Tumoral Circulante/sangue , Metilação de DNA , Neoplasias da Próstata/sangue , Análise Química do Sangue/métodos , DNA Tumoral Circulante/genética , Estudos de Coortes , Humanos , Masculino , Reação em Cadeia da Polimerase/métodos , Neoplasias da Próstata/genética , Reprodutibilidade dos Testes
10.
Clin Chem Lab Med ; 58(8): 1191-1199, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32432563

RESUMO

Coronavirus disease 2019 (COVID-19) represents a new pandemic caused by severe acute respiratory syndrome virus coronavirus 2 (SARS-CoV-2). A previous pooled analysis clearly identified elevated D-dimer levels as being associated with severity of COVID-19. Since then, several other studies have provided clearer support for this initial evidence. However, potentially under-recognized by those reporting on D-dimer is the considerable variation in reporting units for D-dimer, and thus also the potential for misreporting of D-dimer data based on poor or incomplete reporting. A PubMed search was used to identify recent papers reporting on D-dimers in COVID-19-based studies. We report that: (1) most publications did not identify either the manufacturer or D-dimer product used; (2) most did not identify whether D-dimer values were reported as D-dimer units (DDU) or fibrinogen equivalent units (FEU) (~2 × differences); (3) nearly half did not identify normal cut-off values; (4) some did not report numerical findings or units for D-dimer; (5) where reported, most identified units as either mg/L or µg/mL; (6) we identified at least four errors in reporting from 21 papers. It may not be possible to truly standardize D-dimer assays, but it should be feasible to harmonize D-dimer assays to a single unit of measurement.


Assuntos
Análise Química do Sangue/estatística & dados numéricos , Infecções por Coronavirus/sangue , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Pneumonia Viral/sangue , Betacoronavirus , Análise Química do Sangue/métodos , Comunicação , Confusão , Humanos , Pandemias
11.
Adv Exp Med Biol ; 1194: 343-350, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32468550

RESUMO

This paper describes a comprehensive application with three features to diagnose common and rare diseases and to optimize health and vitality of the user with the help of broad databases and state-of-the-art technologies. The features comprise: 1. A digital blood analysis for optimizing the patient's metabolism and health. Individual workout plans are made for the patient's individual body and their individual injuries. Individual meal recommendations are made depending on blood count, needed calories, physical activities, and food allergies of the patient. A digital anamnesis is included in this app. Medical information is digitally stored and made useful for further health-related purposes. 2. A digital and automated diagnosis application that can diagnose more than 7000 common and rare diseases. 3. A food guidance application which provides diet recommendations for the patients based on their physical constitution, physical health aims, allergies, and daily needed calories.


Assuntos
Análise Química do Sangue , Técnicas e Procedimentos Diagnósticos , Educação em Saúde , Software , Análise Química do Sangue/métodos , Aconselhamento/métodos , Bases de Dados Factuais , Técnicas e Procedimentos Diagnósticos/normas , Dieta , Educação em Saúde/métodos , Humanos , Software/normas , Telemedicina
12.
Acute Med ; 19(1): 4-14, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32226951

RESUMO

OBJECTIVE: To ensure clinicians can rely on point-of-care testing results, we assessed agreement between point-of-care tests for creatinine, urea, sodium, potassium, calcium, Hb, INR, CRP and subsequent corresponding laboratory tests. PARTICIPANTS: Community-dwelling adults referred to a community-based acute ambulatory care unit. INTERVENTIONS: The Abbott i-STATTM (Hb, clinical chemistry, INR) and the AfinionTM Analyser (CRP) and corresponding laboratory analyses. OUTCOMES: Agreement (Bland-Altman) and bias (Passing-Bablok regression). RESULTS: Among 462 adults we found an absolute mean difference between point-of-care and central laboratory analyses of 6.4g/L (95%LOA -7.9 to +20.6) for haemoglobin, -0.5mmol/L (95%LOA -4.5 to +3.5) for sodium, 0.2mmol/L (95%LOA -0.6 to +0.9) for potassium, 0.0mmol/L (95%LOA -0.3 to +0.3) for calcium, 9.0 µmol/L (95%LOA -18.5 to +36.4) for creatinine, 0.0mmol/L (95%LOA -2.7 to +2.6) for urea, -0.2 (95%LOA -2.4 to +2.0) for INR, -5.0 mg/L (95%LOA -24.4 to +14.4) for CRP. CONCLUSIONS: There was acceptable agreement and bias for these analytes, except for haemoglobin and creatinine.


Assuntos
Assistência Ambulatorial , Análise Química do Sangue/métodos , Testes Imediatos , Adulto , Humanos , Reprodutibilidade dos Testes
13.
Clin Chem ; 66(4): 579-586, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32232452

RESUMO

BACKGROUND: Insulin-like growth factor-I (IGF-1) is measured mainly by immunoassay for the diagnosis and treatment of growth hormone (GH) disorders, and to detect misuse of GH in sport. Immunoassays often have insufficient inter-laboratory agreement, especially between commercial kits. Over the expected range of IGF-1 in blood (∼50-500 ng/mL), in an inter-laboratory study we previously established a measurement imprecision of 11% (%CV) for the digested protein analyzed by LC-MS. Measuring intact IGF-1 by LC-MS should be simpler. However, no inter-laboratory agreement has been published. METHODS: Intact and trypsin-digested IGF-1 in 32 serum samples from healthy volunteers and human growth hormone administration studies were analyzed by LC-MS using different instruments in five laboratories, as well as by immunoassay in a single laboratory. Another 100 samples were analyzed for IGF-1, both intact and after trypsin-digestion, in each laboratory by LC-MS. The statistical relationship between measurements and the imprecision of each assay group was assessed. RESULTS: An intra-laboratory variability of 2-4% CV was obtained. Inter-laboratory variability was greater at 14.5% CV. Orthogonal regression of intact versus trypsin-digestion methods (n = 646) gave a slope of 1.01 and intercept of 2.05 ng/mL. CONCLUSIONS: LC-MS measurements of IGF-1 by intact and trypsin-digestion methods are not statistically different and each is similar to immunoassay. The two LC-MS approaches may be used interchangeably or together to eliminate concerns regarding an immunoassay IGF-1 measurement. Because intact and digested IGF-1 measurements generally agreed within 20% of each other, we propose this as a criterion of assay acceptability.


Assuntos
Análise Química do Sangue/métodos , Fator de Crescimento Insulin-Like I/análise , Espectrometria de Massas/métodos , Análise Química do Sangue/normas , Feminino , Voluntários Saudáveis , Humanos , Imunoensaio , Laboratórios , Masculino , Espectrometria de Massas/normas
15.
Biosensors (Basel) ; 10(3)2020 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-32121452

RESUMO

Surgical site infection represents a large burden of care in the National Health Service. Current methods for diagnosis include a subjective clinical assessment and wound swab culture that may take several days to return a result. Both techniques are potentially unreliable and result in delays in using targeted antibiotics. Volatile organic compounds (VOCs) are produced by micro-organisms such as those present in an infected wound. This study describes the use of a device to differentiate VOCs produced by an infected wound vs. colonised wound. Malodourous wound dressings were collected from patients, these were a mix of post-operative wounds and vascular leg ulcers. Wound microbiology swabs were taken and antibiotics commenced as clinically appropriate. A control group of soiled, but not malodorous wound dressings were collected from patients who had a split skin graft (SSG) donor site. The analyser used was a G.A.S. GC-IMS. The results from the samples had a sensitivity of 100% and a specificity of 88%, with a positive predictive value of 90%. An area under the curve (AUC) of 91% demonstrates an excellent ability to discriminate those with an infected wound from those without. VOC detection using GC-IMS has the potential to serve as a diagnostic tool for the differentiation of infected and non-infected wounds and facilitate the treatment of wound infections that is cost effective, non-invasive, acceptable to patients, portable, and reliable.


Assuntos
Análise Química do Sangue/métodos , Íons/metabolismo , Infecção dos Ferimentos/diagnóstico , Humanos
16.
Res Vet Sci ; 130: 41-47, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32126390

RESUMO

Blood collection at exsanguination is a method of collecting samples at abattoirs which itself has no effect on animal welfare, compared with collection prior to stunning. However, there is the potential for artefact to affect measurements. It was hypothesised that, for most blood analytes measured, the differences between lairage and exsanguination measurements would be minimal, except for creatine kinase, which was expected be higher in exsanguination samples. Fifty-nine male dairy calves approximately 5-10 days old were sampled prior to slaughter, and again during exsanguination after stunning. Each sample was analysed for packed cell volume, serum urea, beta-hydroxybutyrate, gamma-glutamyl transferase, total protein, glucose and creatine kinase concentrations. Exsanguination and lairage blood results were compared using a paired t-test. There were no significant differences between the measurements taken at exsanguination compared with lairage for packed cell volume, urea and beta-hydroxybutyrate. Glucose concentrations were higher in exsanguination samples, and total protein concentrations were lower, but for both of these analytes the differences were clinically small. Gamma-glutamyl transferase activity was lower in exsanguination samples compared with lairage samples. Creatine kinase activity was higher in exsanguination samples. It was concluded that collecting blood at exsanguination is a valid method for collecting samples for measurement of packed cell volume, urea, and beta-hydroxybutyrate in calves. Glucose and total protein can also yield useful measurements in these samples, though care needs to be taken with interpretation given the minor differences between exsanguination and lairage measurements. Exsanguination samples may be unsuitable for creatine kinase and gamma-glutamyl transferase measurement.


Assuntos
Matadouros , Análise Química do Sangue/veterinária , Coleta de Amostras Sanguíneas/veterinária , Creatina Quinase/análise , Animais , Análise Química do Sangue/métodos , Coleta de Amostras Sanguíneas/métodos , Bovinos , Masculino
17.
Clin Biochem ; 78: 4-9, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32135083

RESUMO

OBJECTIVES: To determine the diagnostic accuracy of a high-sensitivity cardiac troponin I (hs-cTnI) assay in patients presenting to the Emergency Department (ED) with suspected acute coronary syndromes. Specifically, we evaluated the use of a single blood test at the time of arrival in the ED, using low hs-cTnI cut-offs. METHODS: In a prospective diagnostic test accuracy study at 14 centers, we included patients presenting to the ED with suspected ACS within 12 h of symptom onset. We drew blood for hs-cTnI (Siemens ADVIA Centaur, overall 99th percentile 47 ng/L, limit of quantification [LoQ] 2.50 ng/L) on arrival. Patients underwent serial cardiac troponin testing over 3-6 h. The primary outcome was an adjudicated diagnosis of acute myocardial infarction (AMI). We evaluated the incidence of major adverse cardiac events (MACE: death, AMI or revascularization) after 30 days. Test characteristics for hs-cTnI were calculated using previously reported cut-offs set at the LoQ and 5 ng/L. RESULTS: We included 999 patients, including 131 (13.1%) with an adjudicated diagnosis of AMI. Compared to the LoQ (100.0% sensitivity [95% CI 95.9-100.0%]), 99.7% negative predictive value [NPV; 95% CI 97.6-100.0%]), a 5 ng/L cut-off had slightly lower sensitivity (99.2%; 95% CI 95.8-100.0%) and similar NPV (99.8%; 95% CI 98.6-100.0%) but would rule out more patients (28.6% at the LoQ vs 50.4% at 5 ng/L). MACE occurred in 2 (0.7%) patients with hs-cTnI below the LoQ and 7 (1.4%) patients with hs-cTnI < 5 ng/L. Accounting for time from symptom onset or ECG ischemia did not further improve sensitivity. CONCLUSION: The Siemens ADVIA Centaur hs-cTnI assay has high sensitivity and NPV to rule out AMI with a single blood test in the ED. At the LoQ cut-off a sensitivity > 99% can be achieved. At a 5 ng/L cut-off it may be possible to rule out AMI for over 50% patients.


Assuntos
Infarto do Miocárdio/diagnóstico , Troponina I/sangue , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/diagnóstico , Doença Aguda , Adulto , Biomarcadores/sangue , Análise Química do Sangue/métodos , Serviço Hospitalar de Emergência , Feminino , Humanos , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Estudos Prospectivos , Sensibilidade e Especificidade
18.
PLoS One ; 15(2): e0228797, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32074133

RESUMO

(E)-N,N-dimethyl-4-oxo-4-(4-(pyridin-4-yl)phenyl)but-2-enamide hydrochloride (IMB-YH-4py5-2H) is a novel Protein Kinase B (PknB) inhibitor with potent activity against Mycobacterium tuberculosis strains. In the present study, a sensitive and specific liquid chromatography/tandem mass spectrometry (LC-MS/MS) method was developed and validated to determine IMB-YH-4py5-2H in rat plasma. Sample pretreatment was achieved by liquid-liquid extraction with ethyl acetate, and separation was performed on an XTerra MS C18 column (2.1×50 mm, 3.5 µm) with gradient elution (methanol and 0.1% formic acid) at a flow rate of 0.3 mL/min. Detection was performed in multiple reaction monitoring (MRM) mode. Linear calibration curves were obtained over a concentration range of 1-100 ng/mL. The intra-day and inter-day precisions were lower than 8.46%, and the accuracies ranged from -8.71% to 12.36% at all quality control levels. The extraction recoveries were approximately 70%, and the matrix effects were negligible. All quality control samples were stable under different storage conditions. The validated method was successfully applied to a preclinical pharmacokinetic study in Sprague-Dawley rats. IMB-YH-4py5-2H demonstrated improved pharmacokinetic properties (higher exposure level) compared with its leading compound. IMB-YH-4py5-2H was also distributed throughout the lung pronouncedly, especially inside alveolar macrophages, indicating its effectiveness against lower respiratory infections.


Assuntos
Análise Química do Sangue/métodos , Cromatografia Líquida/métodos , Limite de Detecção , Piridinas/sangue , Piridinas/farmacocinética , Espectrometria de Massas em Tandem/métodos , Animais , Antituberculosos/sangue , Antituberculosos/isolamento & purificação , Antituberculosos/farmacocinética , Piridinas/isolamento & purificação , Ratos , Ratos Sprague-Dawley
19.
PLoS One ; 15(2): e0228687, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32012203

RESUMO

INTRODUCTION: Point of care blood testing to aid diagnosis is becoming increasingly common in acute ambulatory settings and enables timely investigation of a range of diagnostic markers. However, this testing allows scope for errors in the pre-analytical phase, which depends on the operator handling and transferring specimens correctly. The extent and nature of these pre-analytical errors in clinical settings has not been widely reported. METHODS: We carried out a convergent parallel mixed-methods service evaluation to investigate pre-analytical errors leading to a machine error reports in a large acute hospital trust in the UK. The quantitative component comprised a retrospective analysis of all recorded error codes from Abbott Point of Care i-STAT 1, i-STAT Alinity and Abbott Rapid Diagnostics Afinion devices to summarise the error frequencies and reasons for error, focusing on those attributable to the operator. The qualitative component included a prospective ethnographic study and a secondary analysis of an existing ethnographic dataset, based in hospital-based ambulatory care and community ambulatory care respectively. RESULTS: The i-STAT had the highest usage (113,266 tests, January 2016-December 2018). As a percentage of all tests attempted, its device-recorded overall error rate was 6.8% (95% confidence interval 6.6% to 6.9%), and in the period when reliable data could be obtained, the operator-attributable error rate was 2.3% (2.2% to 2.4%). Staff identified that the most difficult step was the filling of cartridges, but that this could be improved through practice, with a perception that cartridge wastage through errors was rare. CONCLUSIONS: In the observed settings, the rate of errors attributable to operators of the primary point of care device was less than 1 in 40. In some cases, errors may lead to a small increase in resource use or time required so adequate staff training is necessary to prevent adverse impact on patient care.


Assuntos
Instituições de Assistência Ambulatorial , Análise Química do Sangue/métodos , Erros Médicos , Testes Imediatos , Veias , Humanos
20.
J Chromatogr A ; 1619: 460965, 2020 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-32085913

RESUMO

Fatty acids (FAs) are mostly found in blood as triglycerides, phospholipids (PLs) and cholesteryl esters. Determination of FAs is typically carried out in serum or plasma by a comprehensive method (known as the classical FAMEs method since FAs are determined as Fatty Acids Methyl Esters), which is based on liquid-liquid extraction, derivatization by transesterification, and determination by gas chromatography (GC) coupled to a suited detection technique. However, this method does not favor the determination of FAs that are chemically conjugated in PLs due to kinetics impediment. For this reason, we have developed a selective method to determine the FAs profile of PLs in serum based on solid-phase extraction (SPE) for isolation of PLs and determination of the FAME derivatives by GC-mass spectrometry (GC-MS). The method was applied to serum samples collected from twenty-five individuals to compare the FAs profile versus that provided by the non-selective protocol based on liquid-liquid extraction of lipid families. Statistical analysis revealed compositional changes in the FAs profile with special emphasis on the content of saturated (SFAs) and monounsaturated FAs (MUFAs). Thus, SFAs passed from 34.0% with the classical method to 49.3% in PLs while MUFAs went from 24.4% to 11.4%. This study proves that the proposed method provides complementary results to the comprehensive method and, therefore, both methods can be combined to evaluate the effect of intervention diets and their connection to metabolic diseases.


Assuntos
Análise Química do Sangue/métodos , Ácidos Graxos/sangue , Fosfolipídeos/sangue , Ésteres do Colesterol/análise , Ácidos Graxos/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Extração Líquido-Líquido , Fosfolipídeos/análise , Extração em Fase Sólida , Triglicerídeos/análise
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