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1.
Rev. bras. med. esporte ; 28(6): 775-777, Nov.-Dec. 2022. tab
Artigo em Inglês | LILACS | ID: biblio-1376766

RESUMO

ABSTRACT Introduction This paper studies physiological and biochemical indicators in the systematic training of sprinters. This paper analyzes the data measured during the athletes' training process and studies the detailed data of their physical functions. Objective This study aimed to find a link between exercise data and biochemical indicator data in sprinter athletes. By analyzing the data from this article, the researchers were able to find the optimal training program for the athletes. Methods High-intensity aerobic training tests were performed with statistical analysis of various physiological and biochemical indicators. Results Hemoglobin data were shown to be highly sensitive to intensity. The researchers found that long-term high-load training in athletes can lead to physical fatigue. This fatigue production is positively correlated with the intensity of the training load. Conclusion There is a strong positive correlation between biochemical and physiological indicators on performance levels in sprinter athletes. Evidence Level II; Therapeutic Studies - Investigating the results.


RESUMO Introdução Este artigo estuda o monitoramento de indicadores fisiológicos e bioquímicos no treino sistemático de velocistas. Este documento analisa os dados medidos durante o processo de treino das atletas e estuda os dados detalhados de suas funções físicas. Objetivo O objetivo deste estudo foi encontrar uma ligação entre os dados de exercício e os dados de indicadores bioquímicos nas atletas velocistas. Ao analisar as informações deste artigo, os pesquisadores conseguiram encontrar um programa de treino ideal para as atletas. Métodos Foram empegadas experiências de treino aeróbico de alta intensidade, com análise estatística de vários indicadores fisiológicos e bioquímicos. Resultados Os dados de hemoglobina mostraram-se altamente sensíveis à intensidade. Os pesquisadores descobriram que o treino a longo prazo de alta carga em atletas pode acarretar numa fadiga física. Essa produção de fadiga está positivamente correlacionada com a intensidade da carga de treino. Conclusão Há uma forte correlação positiva entre indicadores bioquímicos e fisiológicos nos níveis de desempenho em atletas velocistas. Nível de evidência II; Estudos Terapêuticos - Investigação de Resultados.


RESUMEN Introducción Este trabajo estudia el seguimiento de los indicadores fisiológicos y bioquímicos en el entrenamiento sistemático de los velocistas. Este artículo analiza los datos medidos durante el proceso de entrenamiento de los atletas y estudia los datos detallados de sus funciones físicas. Objetivo El objetivo de este estudio fue encontrar una relación entre los datos del ejercicio y los datos de los indicadores bioquímicos en los atletas velocistas. Al analizar las informaciones de este artículo, los investigadores pudieron encontrar un programa de entrenamiento óptimo para los atletas. Métodos Se realizaron pruebas de entrenamiento aeróbico de alta intensidad con análisis estadístico de varios indicadores fisiológicos y bioquímicos. Resultados Los datos de la hemoglobina se mostraron muy sensibles a la intensidad. Los investigadores descubrieron que el entrenamiento de alta carga a largo plazo en los atletas puede conducir a la fatiga física. Esta producción de fatiga está positivamente correlacionada con la intensidad de la carga de entrenamiento. Conclusión Existe una fuerte correlación positiva entre los indicadores bioquímicos y fisiológicos en los niveles de rendimiento de los atletas velocistas. Nivel de evidencia II; Estudios terapéuticos - Investigación de resultados.


Assuntos
Humanos , Feminino , Adulto , Adulto Jovem , Corrida/fisiologia , Atletas , Treino Aeróbico , Monitorização Fisiológica/métodos , Testosterona/sangue , Nitrogênio da Ureia Sanguínea , Hemoglobinas/análise , Hidrocortisona/sangue , Radioimunoensaio
2.
Clin Lab ; 68(7)2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35975536

RESUMO

BACKGROUND: The aim of this study was to evaluate the performance of chemiluminescence immunoassays for anti-GAD65 and anti-insulin antibodies following user verification guidelines. METHODS: The analytical performance of anti-GAD65 and anti-insulin antibodies using a MAGLUMI 2000 analyzer was verified following user verification guidelines by the Clinical and Laboratory Standards Institute. RESULTS: Performance specifications including precision, linearity, carry-over, cutoffs for positive results, reference intervals, and comparability with pre-existing commercially available radioimmunoassays using patient specimens and certified reference material were verified (coefficients of variation for precision of anti-GAD65 and anti-insulin antibodies were 2.6% and 3.4%, respectively). Comparability assessed using clinical serum specimens showed overall agreement with radioimmunoassay of 87.2% (95% confidence interval 74.8% - 94.0%) for the anti-GAD65 antibody assay and 85.4% (95% confidence interval 71.6% - 93.1%) for the anti-insulin antibody assay. CONCLUSIONS: The results of this study verified the analytical performance of MAGLUMI anti-GAD65 and anti-insulin antibody assays for clinical use.


Assuntos
Diabetes Mellitus Tipo 1 , Glutamato Descarboxilase , Autoanticorpos , Humanos , Radioimunoensaio/métodos , Valores de Referência
3.
Appl Radiat Isot ; 185: 110261, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35500507

RESUMO

Radioimmunoassay (RIA) is one of the most routine laboratory tests for diagnosing thyroid disease. Patients might receive iodine in the form of intravenous iodinated radiographic contrast media (IRCM) before testing of serum thyroxin (T4) or triiodothyronine (T3) concentration by RIA. The objective was to determine the effect of IRCM on T4 and T3 hormone tests in normal, hypothyroid, and hyperthyroid hormone conditions by RIA. IRCMs (0, 2.5, 5 and 10 mgI/mL) used in this study were iopromide and iodixanol. RIA was determined by commercial T4 RIA kit and T3 RIA kits. The method suggested by the manufacturer was followed. Normal, hypothyroid, and hyperthyroid hormones condition were 1.2 ng/mL, 0.2 ng/mL and 2.2 ng/mL for T3 hormone concentration and 70 ng/mL, 30 ng/mL and 140 ng/mL for T4 hormone concentration, respectively. %Bound values were compared between IRCM-incubated groups and non-incubated group. The data showed that iopromide-incubated groups did not statistically significant change %bound values of T3 and T4 hormone tests in normal, hypothyroid, and hyperthyroid conditions, compared to the non-incubated group. In the same way, %bound values of T3 and T4 hormone tests in iodixanol-incubated groups did not change at all conditions when compared to the non-incubated group. This finding suggested that iodinated radiographic contrast media was unlikely to result in significant problems with radioimmunoassay for measuring T3 and T4 thyroid hormones.


Assuntos
Hipertireoidismo , Hipotireoidismo , Meios de Contraste , Humanos , Hipertireoidismo/diagnóstico por imagem , Hipotireoidismo/diagnóstico por imagem , Radioimunoensaio/métodos , Hormônios Tireóideos , Tri-Iodotironina
4.
Sleep ; 45(7)2022 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-35512685

RESUMO

STUDY OBJECTIVES: The most sensitive and specific investigative method for the diagnosis of narcolepsy type 1 (NT1) is the determination of hypocretin-1 (orexin-A) deficiency (≤110 pg/mL) in cerebrospinal fluid using a radioimmunoassay (RIA). We aimed to assess the reliability of the Phoenix Pharmaceuticals hypocretin-1 RIA, by determining the lower limit of quantification (LLOQ), the variability around the cutoff of 110 pg/mL, and the inter- and intra-assay variability. METHODS: Raw data of 80 consecutive hypocretin-1 RIAs were used to estimate the intra- and inter-assay coefficient of variation (CV). The LLOQ was established and defined as the lowest converted concentration with a CV <25%; the conversion is performed using a harmonization sample which is internationally used to minimize variation between RIAs. RESULTS: The mean intra-assay CV was 4.7%, while the unconverted inter-assay CV was 28.3% (18.5% excluding 2 outliers) and 7.5% when converted to international values. The LLOQ was determined as 27.9 pg/mL. The intra-assay CV of RIAs with lower specific radioactive activity showed a median of 5.6% (n = 41, range 1.6%-17.0%), which was significantly higher than in RIAs with higher specific activity (n = 36; median 3.2%, range 0.4%-11.6%, p = .013). The CV around the 110 pg/mL cutoff was <7%. CONCLUSIONS: Hypocretin-1 RIAs should always be harmonized using standard reference material. The specific activity of an RIA has a significant impact on its reliability, because of the decay of 125I radioactivity. Values around the hypocretin-1 cut-off can reliably be measured. Hypocretin-1 concentrations below 28 pg/mL should be reported as "undetectable" when measured with the Phoenix Pharmaceuticals RIA. CLINICAL TRIAL INFORMATION: This study is not registered in a clinical trial register, as it has a retrospective database design.


Assuntos
Radioisótopos do Iodo , Narcolepsia , Humanos , Narcolepsia/líquido cefalorraquidiano , Narcolepsia/diagnóstico , Orexinas/líquido cefalorraquidiano , Preparações Farmacêuticas , Radioimunoensaio/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos
5.
Urol Oncol ; 40(5): 193.e15-193.e20, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35437219

RESUMO

INTRODUCTION & AIMS: Monitoring testosterone (T) levels is recommended to assess the effectiveness of androgen deprivation therapy (ADT) in advanced prostate cancer. T levels below 20 ng/dL have been associated with better outcomes. Three main measures for T exist including radioimmunoassay (RIA), chemiluminescence assay (CLIA) and mass spectrometry (MS). While CLIA and RIA are ubiquitous, MS is regarded as the reference standard. We set out to determine the discordance of T measurements amongst men on ADT. METHODS: A retrospective review of men with prostate cancer on ADT for ≥3 months was conducted. Serum samples were split in triplicate. Observational data was reported and T measurements were compared analyzing for variability looking for categorical concordance. Over and under-estimation rates were calculated. RESULTS: Ninety-five patients were included with a mean age of 70 (50-92) years. Mean ADT duration was 24.1 (3-144) months. Ninety-five percent of patients had T ≤20ng/dL by MS and CLIA as compared to only 80% by RIA. After subdividing into T categories of ≤20, 20 to 50 and ≥50 ng/dL concordance analysis showed that 4.3% and 18.9% of T measured by MS would have a different category result when remeasured by CLIA (Kappa 0.84) or RIA (Kappa 0.50) respectively. CLIA and RIA overestimated T in 66.7% of patients with T <20 ng/dL measured by MS. Conversely CLIA and RIA underestimated T in only 4.4% of cases with T >20 ng/dL measured by MS. CONCLUSIONS: There is significant variability in T measured with RIA, CLIA and MS. CLIA and RIA overestimated T levels in majority of patients leaving a concern of misdiagnosing truly castrate patients as being inadequately treated.


Assuntos
Antagonistas de Androgênios , Neoplasias da Próstata , Idoso , Androgênios , Cromatografia Líquida/métodos , Humanos , Luminescência , Masculino , Neoplasias da Próstata/tratamento farmacológico , Radioimunoensaio/métodos , Espectrometria de Massas em Tandem/métodos , Testosterona
6.
J Am Vet Med Assoc ; 260(9): 1041-1047, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35417417

RESUMO

OBJECTIVE: To evaluate the urine cortisol-to-creatinine ratio (UCCR) for the diagnosis of hypoadrenocorticism (HA) in dogs and to determine whether the method of urine cortisol measurement affects results. ANIMALS: 41 dogs with naturally occurring HA and 107 dogs with nonadrenal illness. PROCEDURES: Urine samples were prospectively collected from dogs undergoing testing for HA. Urine cortisol concentrations were measured at a veterinary diagnostic laboratory using either a radioimmunoassay (RIA) or a chemiluminescent immunoassay (CLIA). Receiver operating characteristic (ROC) curves were constructed to assess UCCR performance by both methods for HA diagnosis. Sensitivities, specificities, accuracies, and predictive values were calculated for various cutpoints. RESULTS: The areas under the ROC curves for UCCR diagnosis of HA were 0.99 (95% CI, 0.98 to 1.00) and 1.00 (95% CI, 1.00 to 1.00) when urine cortisol was determined by RIA and CLIA, respectively. An RIA UCCR of ≤ 2 was 97.2% sensitive, 93.6% specific, and 94.7% accurate for HA diagnosis, whereas a CLIA UCCR of ≤ 10 was 100% sensitive, specific, and accurate. An RIA UCCR > 4 and a CLIA UCCR of > 10 had negative predictive values of 100%. CLINICAL RELEVANCE: The UCCR was an accurate diagnostic test for HA in this study population, although equivocal results are possible. Case characteristics, method of cortisol measurement, and laboratory-specific cutpoints must be considered when interpreting results.


Assuntos
Insuficiência Adrenal , Doenças do Cão , Insuficiência Adrenal/diagnóstico , Insuficiência Adrenal/veterinária , Animais , Creatinina/urina , Doenças do Cão/diagnóstico , Doenças do Cão/urina , Cães , Hidrocortisona , Radioimunoensaio/veterinária , Urinálise/veterinária
7.
Drug Test Anal ; 14(8): 1438-1450, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35368147

RESUMO

This paper aimed to assess a method to measure eight thyroid-related compounds in serum by liquid chromatography-mass spectrometry (LC-MS/MS), to verify the correlation with radioimmunoassay (RIA), to evaluate the possible cross-reactivity, and to observe differences between athletes declaring the consumption of sodium levothyroxine and nonathletes serum samples. Validation was carried out to assess carryover, working range and linearity, limit of detection and limit of quantification, precision, matrix influence, recovery, accuracy, and uncertainty. Comparison between RIA and LC-MS/MS results was done. The assay was applied to serum samples, and comparison with RIA was done for T3 and T4 levels supported by RIA Thyroid-stimulating hormone (TSH) measurements. Validation parameters showed satisfactory results. Correlation between RIA and LC-MS/MS for T3 and T4 showed good results, but a cross-reactivity between T3 and T3AA was observed. Although no significant differences were proved, preliminary comparison between athletes and nonathletes serum samples showed a shift towards high values of TSH and lower for T4 values in the athletes' group. Differences between thyronine and T4AA concentrations and ratios were observed. The trend of T4 values supported by TSH measures might indicate subclinical hypothyroidism in athletes. This represents one of the most controversial thyroid statuses as different criteria about its treatment are described, especially since one of the exogenous causes is inadequate levothyroxine therapy. Because the variation of thyroid hormones and TSH has been extensively studied in high-performance sports, it is worth considering the need to set an adequate reference interval to accurately assess the thyroid status in athletes.


Assuntos
Espectrometria de Massas em Tandem , Hormônios Tireóideos , Cromatografia Líquida/métodos , Humanos , Radioimunoensaio , Espectrometria de Massas em Tandem/métodos , Tireotropina
8.
Biomolecules ; 12(3)2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35327658

RESUMO

Methods for glucagon analysis suffered in the past from lack of specificity and a narrow sensitivity range, which has led to inaccurate results and to the suggestion that type 1 diabetes (T1D) and type 2 diabetes (T2D) patients have elevated fasting glucagon levels. However, the availability of more specific and more sensitive methods to detect intact glucagon has shown that actual glucagon levels are lower than previously assumed. This study aimed to characterize fasting plasma glucagon levels in healthy individuals and T1D and T2D patients with two different glucagon assays. The study included 20 healthy individuals, 20 T1D and 20 T2D patients. Blood was collected under fasting conditions. A double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) and a conventional radioimmunoassay (RIA) were used. A significant difference in fasting glucagon levels between healthy individuals and T2D was observed by ELISA, but not by RIA. ELISA also yielded lower glucagon levels in healthy individuals than in T1D and T2D patients which RIA did not. RIA produced significantly (p = 0.0001) higher overall median glucagon values than ELISA in a pooled analysis. These results underline the notion that the choice of selective laboratory methods is highly relevant for mechanistic endocrine research.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 2/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Glucagon , Humanos , Radioimunoensaio
10.
Ann Biol Clin (Paris) ; 80(1): 91-95, 2022 Feb 01.
Artigo em Francês | MEDLINE | ID: mdl-35107065

RESUMO

The first step to complete in a method validation of a biological analysis is the study of precision intra-assay. In the absence or insufficient quantity of control material, this study may be difficult to perform. This article proposes a methodology for preparing its own control samples for the radioimmunological assay of the amino-terminal peptide of procollagene type III (PIIIP). This methodology is easy to carry out, cost-effective and can be applied to analyses other than PIIIP. Furthermore, it allows the execution of control samples which have similar concentrations of analytes to those described in the precision studies of the datasheets provided by the manufacturers.


Assuntos
Fragmentos de Peptídeos , Pró-Colágeno , Humanos , Radioimunoensaio
11.
Endocr J ; 69(1): 45-54, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-34305069

RESUMO

A commutability confirmation test for the blood aldosterone measurement was performed on liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) as a designated comparison method (DCM) and four chemiluminescent enzyme immunoassay (CLEIA) measurement procedures based on metrological traceability. A conventional radioimmunoassay (RIA) and two measurement procedures of CLEIA which obtains RIA equivalent values were also compared. The relationship between the DCM value and the CLEIA value with respect to 120 pg/mL of the RIA value, which is the screening criterion of primary aldosteronism (PA) was clarified. For the correlation test, 75 samples of patient serum and plasma were used. Regression analysis revealed that the standardized LC-MS/MS and four CLEIA measurement procedures were in good agreement. This is the effect of measurement specificity and calibration using by certified reference material (CRM). The median of the LC-MS/MS corresponding to 120 pg/mL of RIA was 48.5 pg/mL. In the mean of standardized four CLEIA values corresponding to the 48.5 pg/mL of LC-MS/MS value was 47.51 pg/mL and the standard deviation (SD) was 2.93 pg/mL. However, the correlation between the RIA value and the RIA equivalent of the two measurement procedures by CLEIA differed depending on the measurement procedure. This is due to the influence of RIA measurement performance. Standardized CLEIA measurements are suitable for routine measurement procedure. When converting the LC-MS/MS equivalent value by the standardized CLEIA to the conventional RIA value, it is necessary to use the conversion formula.


Assuntos
Aldosterona , Espectrometria de Massas em Tandem , Cromatografia Líquida/métodos , Humanos , Técnicas Imunoenzimáticas , Radioimunoensaio/métodos , Espectrometria de Massas em Tandem/métodos
12.
J Vet Diagn Invest ; 34(1): 90-93, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34470514

RESUMO

Determination of serum or plasma progesterone (P4) concentrations is important to recognize pregnant and non-pregnant ewes, and also to predict the number of carried lambs. The 2 most common methodologies for the detection of plasma P4 are radioimmunoassay (RIA) and enzyme immunoassay (EIA). RIA is very expensive, and not all laboratories are equipped to perform this test; EIA is commercially available for human use, but only a few companies produce species-specific kits, which are expensive. We verified for ovine plasma a less expensive and easily available ELISA kit (DiaMetra) designed to quantify P4 in humans. Pools of ovine and human plasma were used to compare repeatability, accuracy, sensitivity, and stability of P4 measured by the DiaMetra kit. Repeatability data were within 15%, and accuracy values were ~90% for both plasma matrices. Stability data showed a loss of <20% for freeze-thaw and <30% for 30-d storage. All parameters were acceptable under international guidelines for method validation. The human ELISA kit was used successfully to quantify plasma P4 in 26 ewes during pregnancy until delivery. P4 concentrations were also correlated with the number of carried lambs.


Assuntos
Progesterona , Animais , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Humanos , Técnicas Imunoenzimáticas , Gravidez , Radioimunoensaio/veterinária , Ovinos
13.
J Immunoassay Immunochem ; 43(3): 233-249, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-34672902

RESUMO

This study aimed to purify human chorionic gonadotropin (HCG) from the urine of pregnant women with high biological activity (10811 IU/mg) and purity (98.2%), by simple capturing of HCG using DEAE Sepharose FF and polishing using Sephacryl S200 HR. The HCG obtained was characterized by SDS-PAGE and dissociated into alpha and beta subunits using the urea treatment method. The ßHCG subunits were injected into rabbits for the production of highly specific polyclonal anti-ßHCG antisera. The polyclonal anti-ßHCG was locally produced in rabbits and assessed for binding titer (1/10000), displacement (84.8%), and specificity (98.8%). Purified HCG along with locally prepared polyclonal anti-ßHCG antisera were used as basic components of the in-house Radioimmunoassay system for quantitative estimation of HCG in human serum.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta , Gonadotropina Coriônica , Animais , Gonadotropina Coriônica/urina , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Soros Imunes , Gravidez , Coelhos , Radioimunoensaio/métodos
14.
Eur J Neurol ; 29(2): 564-572, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34710286

RESUMO

BACKGROUND AND PURPOSE: This study was undertaken to assess the long-term outcome of patients with paraneoplastic and non paraneoplastic autoimmune cerebellar ataxia (ACA) using the Scale for the Assessment and Rating of Ataxia (SARA). METHODS: Patients with subacute cerebellar ataxia admitted to our institution between September 2012 and April 2020 were prospectively recruited. Serum and/or cerebrospinal fluid was tested for neural autoantibodies by indirect immunofluorescence on mouse brain, cell-based assays, and radioimmunoassay. SARA and modified Rankin Scale (mRS) score were employed to assess patients' outcome. RESULTS: Fifty-five patients were recruited, of whom 23 (42%) met the criteria for cerebellar ataxia of autoimmune etiology. Neural autoantibodies were detected in 22 of 23 patients (Yo-immunoglobulin G [IgG], n = 6; glutamic acid decarboxylase 65-IgG, n = 3; metabotropic glutamate receptor 1-IgG, n = 2; voltage-gated calcium channel P/Q type-IgG, n = 2; Hu-IgG, n = 1; glial fibrillary acidic protein-IgG, n = 1; IgG-binding unclassified antigens, n = 7). Thirteen patients were diagnosed with paraneoplastic cerebellar syndrome (PCS) and 10 with idiopathic ACA. All patients received immunotherapy. Median SARA score was higher in the PCS group at all time points (p = 0.0002), while it decreased significantly within the ACA group (p = 0.049) after immunotherapy. Patients with good outcome (mRS ≤ 2) had less neurological disability (SARA < 15) at disease nadir (p = 0.039) and presented less frequently with paraneoplastic neurological syndrome (p = 0.0028). The univariate linear regression model revealed a good correlation between mRS and SARA score both at disease onset (p < 0.0001) and at last follow-up (p < 0.0001). SARA score < 11 identified patients with good outcome. CONCLUSIONS: Patients with idiopathic ACA significantly improved after immunotherapy. SARA score accurately reflects patients' clinical status and may be a suitable outcome measure for patients with ACA.


Assuntos
Ataxia Cerebelar , Animais , Autoanticorpos , Ataxia Cerebelar/diagnóstico , Ataxia Cerebelar/terapia , Humanos , Fatores Imunológicos/uso terapêutico , Imunoterapia , Camundongos , Radioimunoensaio
15.
J Hum Hypertens ; 36(1): 77-85, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33564064

RESUMO

Determination of plasma aldosterone concentrations (PAC) and plasma active renin concentrations (ARC) is essential for the diagnosis of primary aldosteronism (PA). In Japan, although PAC and ARC are measured by radioimmunoassay and immunoradiometric assay, respectively, non-radioisotopic methods with better detection sensitivity, measurement accuracy, and technical simplicity are needed. We developed two-site sandwich chemiluminescent enzyme immunoassays (CLEIAs) to measure both PAC and ARC using monoclonal antibodies immobilized onto ferrite particles. The results of both assays are obtained simultaneously from a single plasma sample within 30 min using a fully automated system. The novel CLEIAs were validated using plasma samples from patients with PA (n = 52) and essential hypertension (n = 23). The PAC determined by the CLEIA was significantly correlated with that measured by liquid chromatography/mass spectrometry or conventional radioimmunoassay. The ARC determined by the CLEIA was significantly correlated with that measured by immunoradiometric assay. The limits of detection of the CLEIAs for PAC and ARC were 0.1 ng/dl and 0.04 pg/ml, respectively, which were better than those of conventional methods (PAC: 2.5 ng/dl; ARC: 5 pg/ml). The PAC and PAC/ARC ratio (ARR) were significantly higher, and the ARC significantly lower, in patients with PA than in those with essential hypertension. An ARR cut-off of 1.31 ng/dl per pg/ml showed a sensitivity of 96.2% and specificity of 78.3% for PA screening. The newly developed CLEIAs for measuring PAC and ARC could provide a clinically powerful alternative to conventional methods used for hypertension screening in clinical practice.


Assuntos
Hiperaldosteronismo , Hipertensão , Aldosterona , Hipertensão Essencial/diagnóstico , Humanos , Hiperaldosteronismo/diagnóstico , Hipertensão/diagnóstico , Radioimunoensaio , Renina
16.
Endokrynol Pol ; 72(6): 668-669, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34855198

RESUMO

INTRODUCTION: Thyroid hormone autoantibody (THAAb) is one of the important factors affecting thyroid function measurement. By analyzing the examination of a patient suffered with Hashimoto's thyroiditis, we sought to find a correct assessment method. MATERIAL AND METHODS: Radioimmunoassay, chemiluminescence immunoassay on an ADVIA Centaur XP system and Architect i2000sr platform, and electrochemiluminescence immunoassay on a Roche Cobas 601 system were used for detecting thyroid function. Polyethylene glycol (PEG) precipitation were performed to eliminate the influence of THAAbs. RESULTS: The results showed that the patient's thyroid function was consistent with the clinical manifestations and conformed to the law of the hypothalamic-pituitary-thyroid axis at Architect-i2000sr platform and Roche-Cobas-601 system. The content of FT4 was significantly reduced and lower than the normal reference range, after the patients' serum was treated with PEG, which was in line with the clinical practice. The serum THAAb titer of the patients was nearly 100 times higher than that of the control group. CONCLUSIONS: Considering an abnormal thyroid function examination, it is necessary for laboratory staff to retest samples on different platforms. It is of great significance to provide a true and accurate result to clinicians and patients.


Assuntos
Autoanticorpos/análise , Doença de Hashimoto/diagnóstico , Testes de Função Tireóidea/métodos , Hormônios Tireóideos/imunologia , Tiroxina/sangue , Antígenos de Neoplasias/sangue , Autoanticorpos/imunologia , Feminino , Doença de Hashimoto/sangue , Humanos , Pessoa de Meia-Idade , Proteínas de Neoplasias/sangue , Radioimunoensaio , Tiroxina/imunologia
17.
PLoS One ; 16(11): e0260131, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34793577

RESUMO

BACKGROUND: Endogenous ouabain (EO) and atrial natriuretic peptide (ANP) are important in regulation of sodium and fluid balance. There is indirect evidence that ANP may be involved in the regulation of endogenous cardenolides. METHODS: H295R are human adrenocortical cells known to release EO. Cells were treated with ANP at physiologic concentrations or vehicle (0.1% DMSO), with or without guanylyl cyclase inhibitor 1,2,4 oxadiazolo[4,3-a]quinoxalin-1-one (ODQ). Cyclic guanosine monophosphate (cGMP), the intracellular second messenger of ANP, was measured by a chemiluminescent immunoassay and EO was measured by radioimmunoassay of C18 extracted samples. RESULTS: EO secretion is inhibited by ANP treatment, with the most prolonged inhibition (90 min vs ≤ 60 min) occurring at physiologic ANP concentrations (50 pg/mL). Inhibition of guanylyl cyclase with ODQ, also reduces EO secretion. The inhibitory effects on EO release in response to cotreatment with ANP and ODQ appeared to be additive. CONCLUSIONS: ANP inhibits basal EO secretion, and it is unlikely that this is mediated through ANP-A or ANP-B receptors (the most common natriuretic peptide receptors) or their cGMP second messenger; the underlying mechanisms involved are not revealed in the current studies. The role of ANP in the control of EO synthesis and secretion in vivo requires further investigation.


Assuntos
Fator Natriurético Atrial/farmacologia , Ouabaína/antagonistas & inibidores , Ouabaína/metabolismo , Córtex Suprarrenal/metabolismo , Fator Natriurético Atrial/metabolismo , Linhagem Celular Tumoral , GMP Cíclico/análise , Guanilato Ciclase/metabolismo , Humanos , Oxidiazóis/farmacologia , Fragmentos de Peptídeos/metabolismo , Quinoxalinas/farmacologia , Radioimunoensaio/métodos , Receptores do Fator Natriurético Atrial/metabolismo , Receptores de Superfície Celular/metabolismo , Sistemas do Segundo Mensageiro/efeitos dos fármacos , Vasodilatadores/farmacologia
18.
PLoS One ; 16(9): e0257422, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34529698

RESUMO

OBJECTIVE: To determine if maternal plasma CRH and preterm birth history were associated with recurrent preterm birth risk in a high-risk cohort. STUDY DESIGN: Secondary analysis of pregnant women with a prior preterm birth ≤35 weeks receiving 17-alpha hydroxyprogesterone caproate for the prevention of recurrent spontaneous preterm birth. All women with a 24-week blood sample were included. Maternal plasma CRH level at 24- and 32-weeks' gestation was measured using both enzyme-linked immunosorbent assay (ELISA) and extracted radioimmunoassay (RIA) technologies. The primary outcome was spontaneous preterm birth <37 weeks. The association of CRH, prior preterm birth history, and the two combined was assessed in relation to recurrent preterm birth risk. RESULTS: Recurrent preterm birth in this cohort of 169 women was 24.9%. Comparing women who subsequently delivered <37 versus ≥37 weeks, mean levels of CRH measured by RIA were significantly different at 24 weeks (111.1±87.5 vs. 66.1±45.4 pg/mL, P = .002) and 32 weeks (440.9±275.6 vs. 280.2±214.5 pg/mL, P = .003). The area under the receiver operating curve (AUC) at 24 and 32 weeks for (1) CRH level was 0.68 (95% CI 0.59-0.78) and 0.70 (95% CI 0.59-0.81), (2) prior preterm birth history was 0.75 (95% CI 0.67-0.83) and 0.78 (95% CI 0.69-0.87), and (3) combined was 0.81 (95% CI 0.73-0.88, P = .001) and 0.81 (95% CI 0.72-0.90, P = .01) respectively for delivery <37 weeks. CRH measured by ELISA failed to correlate with gestational age or other clinical parameters. CONCLUSION: In women with a prior preterm birth, CRH levels were higher and had an earlier rise in women who experienced recurrent preterm birth. Second trimester CRH may be useful in identifying a sub-group of women with preterm birth due to early activation of the placenta-fetal adrenal axis. Assay methodology is a variable that contributes to difficulties in reproducibility of CRH levels in the obstetric literature.


Assuntos
Hormônio Liberador da Corticotropina/sangue , Placenta/metabolismo , Nascimento Prematuro , Caproato de 17 alfa-Hidroxiprogesterona/administração & dosagem , Adulto , Área Sob a Curva , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática , Feminino , Idade Gestacional , Humanos , Gravidez , Resultado da Gravidez , Cuidado Pré-Natal , Estudos Prospectivos , Curva ROC , Radioimunoensaio , Fatores de Risco , Regulação para Cima
19.
Am J Nurs ; 121(10): 67, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34554993

RESUMO

Stories of discovery, wrong turns, and hope.


Assuntos
Nível de Alerta , Endocrinologia , Hormônios , Hormônios/análise , Hormônios/fisiologia , Humanos , Radioimunoensaio
20.
Sci Rep ; 11(1): 14286, 2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34253766

RESUMO

We examined the effect of total and afferent renal denervation (RDN) on hypertension and the renin-angiotensin system (RAS) in a rodent model of juvenile-onset polycystic kidney disease (PKD). Lewis Polycystic Kidney (LPK) and control rats received total, afferent or sham RDN by periaxonal application of phenol, capsaicin or normal saline, respectively, and were monitored for 4-weeks. Afferent RDN did not affect systolic blood pressure (SBP) determined by radiotelemetry in either strain (n = 19) while total RDN significantly reduced SBP in Lewis rats 4-weeks post-denervation (total vs. sham, 122 ± 1 vs. 130 ± 2 mmHg, P = 0.002, n = 25). Plasma and kidney renin content determined by radioimmunoassay were significantly lower in LPK vs. Lewis (plasma: 278.2 ± 6.7 vs. 376.5 ± 11.9 ng Ang I/ml/h; kidney: 260.1 ± 6.3 vs. 753.2 ± 37.9 ng Ang I/mg/h, P < 0.001, n = 26). These parameters were not affected by RDN. Intrarenal mRNA expression levels of renin, angiotensinogen, angiotensin-converting enzyme (ACE)2, and angiotensin II receptor type 1a were significantly lower, whereas ACE1 expression was significantly higher in the LPK vs. Lewis (all P < 0.05, n = 26). This pattern of intrarenal RAS expression was not changed by RDN. In conclusion, RDN does not affect hypertension or the RAS in the LPK model and indicates RDN might not be a suitable antihypertensive strategy for individuals with juvenile-onset PKD.


Assuntos
Denervação , Hipertensão/complicações , Rim/inervação , Rim/fisiopatologia , Doenças Renais Policísticas/fisiopatologia , Sistema Renina-Angiotensina , Animais , Anti-Hipertensivos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Rim/cirurgia , Masculino , RNA Mensageiro/metabolismo , Radioimunoensaio , Ratos , Ratos Endogâmicos Lew , Renina/metabolismo
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