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1.
Anal Biochem ; 684: 115371, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37940014

RESUMO

Genetic testing has been increasingly used in several fields. In many applications, nucleic acid amplification technology is required. However, current methods to detect nucleic acid amplification require expensive reagents and special equipment or exhibit limited sensitivity, which hinders their use. To address this issue, this study reports an assay method for detecting occurrence of acid amplification in post-amplification samples using pyrophosphate, a highly sensitive byproduct of nucleic acid amplification. The method proposed requires two reagents and an automated analyzer. First, hydrogen peroxide is derived from pyrophosphate, an indicator of nucleic acid amplification, and the oxidizing power of hydrogen peroxide is used to produce Fe (III) from Fe (II). The specific metal chelator 5-Br-PAPS forms a complex with the trivalent iron produced, resulting in a highly sensitive coloration. The within-run reproducibility of our method (n = 20) was less than 3.67% at each concentration tested, and the detection limit was 0.075 µmol/L, sufficient for quantitative analysis. The technique described could detect pyrophosphate in a sample that was amplified using the loop-mediated isothermal amplification method after only 10 min. Therefore, the proposed method has the potential to be a new, rapid, and simple detection technique for amplified nucleic acids.


Assuntos
Difosfatos , Ácidos Nucleicos , Sensibilidade e Especificidade , Peróxido de Hidrogênio , Reprodutibilidade dos Testes , Técnicas de Amplificação de Ácido Nucleico/métodos , Ácidos Nucleicos/genética
2.
J Clin Lab Anal ; 36(3): e24276, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35150028

RESUMO

BACKGROUND: Diagnosis of bleeding disorders includes correct analysis of coagulation factors VIII, IX, XI, XII, XIII, II, V, VII, and X and von Willebrand antigen and activity. The aim of this study was to evaluate the analytical performance of the Atellica COAG 360 analyzer in a specialized coagulation laboratory with focus on specific coagulation parameters involved in the diagnosis of bleeding disorders. METHODS: Verification included assessment of precision, reference interval, and method comparison according to local guidelines. For FVIII (Chromogenix) and FIX (Rossix), extended verifications were performed with additional assessment of linearity, detection limit, and comparability to BCS-XP. RESULTS: The precision was below 5% (normal levels) and below 10% (abnormal levels) and either improved or similar when compared to expected target values from a BCS-XP. The locally established reference range agreed well (≥80% of measured values within manufacturer's assigned ranges) for most of the methods. The lower limit of quantification was calculated to below 0.01 IU/ml for FVIII chromogenic (Chromogenix) and FIX chromogenic (Rossix), both with acceptable linearity. Bland-Altman analyses revealed generally good agreement between Atellica COAG 360 and BCS-XP in the determination of coagulation parameters, and differences between the two instruments did not result in any diagnostic change. CONCLUSIONS: The results of the evaluation show that the Atellica COAG 360 analyzer performs as expected to target values and equivalent to BCS-XP for the diagnosis of bleeding disorders in a specialized coagulation laboratory providing service to a hemophilia treatment center (HTC).


Assuntos
Coagulação Sanguínea , Hemofilia A , Testes de Coagulação Sanguínea/métodos , Fator VIII , Humanos , Laboratórios
3.
Ecotoxicol Environ Saf ; 157: 335-342, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29627418

RESUMO

A novel tool, the DAMTA analyzer (Device for Analytical Monitoring and Toxicity Assessment), designed for fully automated toxicity measurements based on luminescent bacteria as well as for concomitant determination of chemical parameters, was developed and field-tested. The instrument is a robotic water analyzer equipped with a luminometer and a spectrophotometer, integrated on a thermostated reaction plate which contains a movable carousel with 80 cuvettes. Acute toxicity is measured on-line using a wild type Photobacterium phosphoreum strain with measurable bioluminescence and unaltered sensitivity to toxicants lasting up to ten days. The EC50 values of reference compounds tested were consistent with A. fischeri and P. phosphoreum international standards and comparable to previously published data. Concurrently, a laboratory trial demonstrated the feasibility of use of the analyzer for the determination of nutrients and metals in parallel to the toxicity measurements. In a prolonged test, the system was installed only in toxicity mode at the premises of the World Fair "Expo Milano-2015″, a high security site to ensure the quality of the supplied drinking water. The monitoring program lasted for six months during which ca. 2400 toxicity tests were carried out; the results indicated a mean non-toxic outcome of -5.5 ±â€¯6.2%. In order to warrant the system's robustness in detecting toxic substances, Zn was measured daily with highly reproducible inhibition results, 70.8 ±â€¯13.6%. These results assure that this novel toxicity monitor can be used as an early warning system for protection of drinking water sources from emergencies involving low probability/high impact contamination events in source water or treated water.


Assuntos
Água Potável/análise , Monitoramento Ambiental/instrumentação , Robótica , Poluentes Químicos da Água/toxicidade , Abastecimento de Água/normas , Água Potável/normas , Monitoramento Ambiental/métodos , Desenho de Equipamento , Itália , Medições Luminescentes , Photobacterium/efeitos dos fármacos , Testes de Toxicidade/instrumentação , Testes de Toxicidade/métodos , Poluentes Químicos da Água/análise
4.
J Avian Med Surg ; 29(3): 181-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26378663

RESUMO

Biochemical analysis is necessary for diagnosis and monitoring of diseases in birds; however, the small volume of blood that can be safely obtained from small avian species often limits laboratory diagnostic testing. Consequently, a suitable methodology requiring only a small volume of blood must be used. This study was designed to compare blood glucose concentrations in domestic pigeons ( Columba livia domestica) as measured by a commercial, handheld, human glucometer and a standard autoanalyzer. During the first phase of the study, whole blood samples obtained from 30 domestic pigeons were used to measure the blood glucose concentration with a glucometer, the packed cell volume (PCV), and the total erythrocyte count (nRBC). Plasma separated from the each sample was then used to obtain the plasma glucose concentration with the autoanalyzer. During the second phase of the study, 30 pigeons were assigned to 2 equal groups (n = 15). Hypoglycemia or hyperglycemia was induced in each group by intravenous injection of insulin or glucose, respectively. Blood was collected and processed, and glucose concentrations, PCV, and nRBC were measured as previously described. Linear-regression models demonstrated a significant relationship between results measured by the glucometer and autoanalyzer results from normoglycemic (correlation coefficient [R] = 0.43, P = .02), hypoglycemic (R = 0.95; P < .001), and hyperglycemic (R = 0.81; P < .001) birds. The results of this study suggest that we can predict the real blood-glucose concentration of pigeons by using results obtained by a glucometer.


Assuntos
Análise Química do Sangue/veterinária , Glicemia/fisiologia , Columbidae/sangue , Sistemas Automatizados de Assistência Junto ao Leito , Animais , Análise Química do Sangue/instrumentação , Glicemia/análise , Reprodutibilidade dos Testes
5.
Vet Clin Pathol ; 53(1): 8-39, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38164989

RESUMO

BACKGROUND: The Sysmex XN-1000V automated hematology analyzer with multispecies software was released in June 2017 for use in research laboratories. Laser light, impedance, fluorescent staining, and fluorescent flow cytometry are used to analyze whole blood for CBC, reticulocyte counts, and WBC counts, including a 5-part differential leukocyte analysis. OBJECTIVES: A side-by-side comparison of the Sysmex XN-1000V with the Siemens ADVIA 120 in analyzing blood from healthy mice and rats will provide insight into the performance of the new analyzer and its capabilities for use in drug development studies. Method correlation analyses on normal mouse and rat hematology data collected with both analyzers and manual reference methods will help determine the reliability of the data produced using the Sysmex XN-1000V analyzer. METHODS: Whole blood samples collected in K2 EDTA from healthy CD-1 mice and CD Sprague-Dawley rats were analyzed in parallel with the XN-1000V and ADVIA 120 analyzers. Male and female mice, approximately 6-9 weeks old, and male and female rats, approximately 7-9 weeks old, were included in this study. Manual reference methods for WBC differential leukocyte analysis and packed cell volume (PCV) measurements were also performed. EP Evaluator version 11.2 (Data Innovations LLC, South Burlington, VT, USA) was used for method comparison statistical analysis. RESULTS: Most hematologic parameters for naïve mice and rats achieved correlation in the fair to excellent range, with the majority showing very good to excellent correlation with low biases (<11.0%) for cohorts analyzed separately and when cohort data were combined. CONCLUSIONS: The Sysmex XN-1000V Hematology Analyzer provided comparable results to those obtained from the Siemens ADVIA 120. We found the Sysmex XN-1000V Hematology Analyzer to be acceptable for use in drug development studies for rats and mice.


Assuntos
Hematologia , Humanos , Masculino , Feminino , Camundongos , Ratos , Animais , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Contagem de Leucócitos/veterinária , Contagem de Reticulócitos/veterinária , Hematologia/métodos
6.
J Clin Med ; 13(8)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38673517

RESUMO

Background: We compared the performance of 21 different assays performed by the Wantai Wan200+ (Wantai BioPharm, Beijing, China) with respect to other methods in use at the University Hospital of Padova (AOPD), Italy. Methods: The plasma (P) or serum (S) of 5027 leftover samples, collected from May to Sept 2023, was either analyzed or frozen at -20 °C. Beckman DXI800 (DXI), Roche Cobas 8000 e801 (RC), Snibe Maglumi 4000 plus (SM), DiaSorin Liaison XL (DL) and Binding Site Optilite (BS) equipment were used at the AOPD. P-procalcitonin (PCT), DXI; P-Troponin I (TnI), DXI; S-CA125, DXI; S-free PSA (f-PSA), DXI; S-total PSA (t-PSA), DXI; S-IL6, SM; P-Troponin T (TnT), RC; P-NT-proBNP, RC; P-Neuron-Specific Enolase (NSE), RC; S-CA15-3, DL; S-CA19-9, DL; S-AFP, DL; and S-CEA, DL were tested in fresh samples. P-Myoglobin (Myo), DXI; P-Cyfra21-1, RC; S-ß2 microglobulin (B2MIC), BS; S-HE4, SM; S-PGI, SM; S-PGII, SM; S-CA72-4, SM; and S-CA50, SM were analyzed in frozen and thawed samples. Bland-Altman (BA), Passing-Bablok (PB) and Cohen's Kappa (CKa) metrics were used as statistics. Results: An excellent comparability profile was found for 11 analytes. For example, the t-PSA CKa was 0.94 (95%CI: 0.90 to 0.98), and the PB slope and intercept were 1.02 (95%CI: 0.99 to 1.03) and 0.02 (95%CI: 0.01 to 0.03), respectively; the BA bias was 2.25 (95%CI: -0.43 to 4.93). Ten tested measurands demonstrated a suboptimal comparability profile. Biological variation in EFLM (EuBIVAS) performance specifications was evaluated to assess the clinical relevance of measured biases. Conclusions: Evaluation of the Wantai Wan200+'s performance suggests that between-method differences did not exceed the calculated bias. Metrological traceability may influence the comparisons obtained for some measurands.

7.
Hematology ; 28(1): 2248433, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37642342

RESUMO

OBJECTIVE: This study aims to evaluate the consistency of heterogeneity degree of erythrocyte volume parameters between the blood automated analyzer Sysmex-XN9000 and the advanced red blood cell software CellaVisionDI-60. METHOD: 500 blood samples of volunteers were analyzed by Sysmex-XN9000 and CellaVision-DI60. The sensitivity, specificity, positive predictive value, negative predictive value, false positive rate, and false negative rate were evaluated. The consistency of all parameters was tested. RESULT: Taking the standard RBC group as the control group, the RBC parameters of the macrocytic and the microcytic group were compared. There was a statistical difference between the groups. ROC curve analysis showed that the best cutoff value of microcytic and of macrocytic affecting MCV were 4.1% and 5.7%, respectively. The best cutoff value of anisocytosis was 15.0%. The correlation coefficient between anisocytosis and red blood cell distribution width (RDW-CV) was 0.756. The sensitivity, specificity, positive predictive value and coincidence rate of anisocytosis were high. The false negative rate was 10.0%, and the false positive rate was 7.4%. CONCLUSION: All parameters of the degree of heterogeneity have good accuracy and consistency in the two instruments. Anisocytosis is with higher coincidence rate and positive predictive value. MIC and MAC have a good prediction on the increase or decrease of MCV. Although advanced RBC software's false negative and false positive rates are high, the red blood cell image system is more intuitive and time-saving in observing cells. Consequently, CellaVision-DI60 is suggested to combine with XN-9000 for judging the anisocytosis in daily work comprehensively.


Assuntos
Índices de Eritrócitos , Eritrócitos , Humanos , Curva ROC , Software
8.
Ann Lab Med ; 42(5): 515-530, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35470271

RESUMO

Automated hematology analyzers generate accurate complete blood counts (CBC) results on nearly all specimens. However, every laboratory encounters, at times, some specimens that yield no or inaccurate result(s) for one or more CBC parameters even when the analyzer is functioning properly and the manufacturer's instructions are followed to the letter. Inaccurate results, which may adversely affect patient care, are clinically unreliable and require the attention of laboratory professionals. Laboratory professionals must recognize unreliable results, determine the possible cause(s), and be acquainted with the ways to obtain reliable results on such specimens. We present a concise overview of the known causes of unreliable automated CBC results, ways to recognize them, and means commonly utilized to obtain reliable results. Some examples of unreliable automated CBC results are also illustrated. Pertinent analyzer-specific information can be found in the manufacturers' operating manuals.


Assuntos
Laboratórios , Contagem de Células Sanguíneas/métodos , Humanos , Contagem de Leucócitos , Reprodutibilidade dos Testes
9.
Talanta ; 237: 122908, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34736645

RESUMO

Here we describe an automated and compact pollen detection system that integrates enrichment, in-situ detection and self-cleaning modules. The system can achieve continuous capture and enrichment of pollen grains in air samples by electrostatic adsorption. The captured pollen grains are imaged with a digital camera, and an automated image analysis based on machine vision is performed, which enables a quantification of the number of pollen particles as well as a preliminary classification into two types of pollen grains. In order to optimize and evaluate the system performance, we developed a testing approach that utilizes an airflow containing a precisely metered amount of pollen particles surrounded by a sheath flow to achieve the generation and lossless transmission of standard gas samples. We studied various factors affecting the pollen capture efficiency, including the applied voltage, air flow rate and humidity. Under optimized conditions, the system was successfully used in the measurement of airborne pollen particles within a wide range of concentrations, spanning 3 orders of magnitude.


Assuntos
Poluentes Atmosféricos , Pólen , Poluentes Atmosféricos/análise , Alérgenos/análise , Processamento de Imagem Assistida por Computador , Pólen/química , Eletricidade Estática
10.
Lab Med ; 53(3): e69-e73, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-34668538

RESUMO

OBJECTIVE: To indicate the ability to disaggregate platelet clumps by vortex mixing and kanamycin supplementation in EDTA-dependent pseudothrombocytopenia (EDTA-PTCP) specimens. MATERIALS AND METHODS: For patients with EDTA-PTCP, citrate-anticoagulated, primary EDTA-anticoagulated, vortex-mixed, and kanamycin-treated specimens were tested for complete blood count and platelet-related parameters. RESULTS: Forty-eight specimens were included. Nineteen (39.6%) of the vortex-mixed specimens and 42 (87.5%) of the kanamycin-treated specimens revealed platelet counts more than those of the primary EDTA specimens, with levels exceeding 100 × 109/L. The platelet count and platelet recovery of the kanamycin-treated specimens were higher than those of the vortex-mixed specimens. CONCLUSION: Kanamycin supplementation to EDTA-PTCP blood may be considered as an alternative approach when the recollection of specimens is impractical. Only platelet-related parameters from kanamycin treatment were suitable for guiding patient management. Further studies about the impact of these methods in patients with various conditions, such as in patients with advanced kidney disease, should be conducted.


Assuntos
Transtornos Plaquetários , Trombocitopenia , Suplementos Nutricionais , Ácido Edético/farmacologia , Humanos , Canamicina/farmacologia , Agregação Plaquetária , Contagem de Plaquetas/métodos
11.
Bioanalysis ; 14(6): 325-340, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35234530

RESUMO

Background: With the spread of COVID-19, anti-SARS-CoV-2 antibody tests have been utilized. Herein we evaluated the analytical performance of anti-SARS-CoV-2 antibody test kits using a new reference standard prepared from COVID-19 patient sera. Methods: Fifty-seven kits in total (16 immunochromatography types, 11 ELISA types and 30 types for automated analyzers) were examined. By measuring serially diluted reference standards, the maximum dilution factor showing a positive result and its precision were investigated. Results: The measured cut-off titers varied largely depending on the antibody kit; however, the variability was small, with the titers obtained by each kit being within twofold in most cases. Conclusion: The current results suggest that a suitable kit should be selected depending on the intended purpose.


Assuntos
Teste Sorológico para COVID-19/métodos , Kit de Reagentes para Diagnóstico , Anticorpos Antivirais/sangue , Automação Laboratorial , Teste Sorológico para COVID-19/instrumentação , Teste Sorológico para COVID-19/normas , Ensaio de Imunoadsorção Enzimática/instrumentação , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Imunoglobulina G/sangue , Japão , SARS-CoV-2/imunologia
12.
J Vet Intern Med ; 35(3): 1439-1447, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33760275

RESUMO

BACKGROUND: Detection of urinary casts is difficult due to their intermittent presence and deterioration in urine samples. OBJECTIVE: To compare the performance of the IDEXX SediVue Dx® Urine Sediment Analyzer (SediVue) with manual microscopy for the detection of urinary casts. We hypothesized that the SediVue analyzer would perform similarly to manual microscopy in cast detection. ANIMALS: Four hundred forty-three samples from 420 dogs from a hospital population. METHODS: This is a prospective, cross-sectional study. For SediVue analysis (software version [SW] 1.0.1.3), uncentrifuged urine was pipetted into a disposable cartridge. Seventy images were captured and processed by an onboard algorithm. For manual microscopy, urine was centrifuged to obtain sediment. Any cast identified by either method was considered a positive result (>0/low-power field [LPF]). SediVue images were evaluated if casts were detected by either methodology. A revised sensitivity and specificity were calculated after image review and when using a threshold of >1 cast/LPF. RESULTS: The sensitivity of the SediVue analysis for the detection of urinary casts was 53.7% (43.85%-63.35%), and specificity was 86.0% (81.78%-89.51%). After image review, the revised sensitivity/specificity was 52.0% (42.89%-61.02%) and 90.6% (86.81%-93.54%), respectively. When using a more clinically relevant threshold of >1/LPF, the sensitivity was 52.6% (35.82%-69.02%) and specificity was 99.3% (97.85%-99.85%). CONCLUSIONS AND CLINICAL IMPORTANCE: The SediVue provides moderate agreement to manual methodology for detection of casts in urine.


Assuntos
Microscopia , Urinálise , Animais , Estudos Transversais , Cães , Microscopia/veterinária , Estudos Prospectivos , Sensibilidade e Especificidade , Urinálise/veterinária
13.
Diagn Pathol ; 16(1): 9, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33482827

RESUMO

BACKGROUND: "Atypical cells" parameter in automated urinalysis has recently been introduced. An instrument capable of measuring quantitative and qualitative features of nuclear and cytoplasmic properties of a cell has the potential to detect cellular atypia. Instruments using flow cytometry have been detecting atypical cells in blood for a long time; yet instruments using the same methodology very lately developed this parameter in urinalysis. MATERIALS AND METHODS: Samples with an atypical cells value higher than 1 atypical cell/µL were included in the study. Besides automated urinalysis, every sample was reflexed to modular unit for digital imaging. The remainder of each sample was stained with Sternheimer dye and examined manually under a light microscope. RESULTS: 50 samples with higher than1 atypical cell/µL result were included in the study. Patients were composed of 43 females (86 %) and 7 males (14 %). The mean age was 47.12 ± 19.45 years. The median atypical cells value was 1.8/µL (95 % range 1.5-2.4/µL). Manual microscopic evaluation of the 50 samples showed atypical cells in 1 sample. The patient had papillary lesions on cystoscopy and pathology report informed a high grade urothelial carcinoma. Other 49 samples were negative for atypical cells in manual microscopy. They were crowded samples with leucocytes and squamous epithelial cells. CONCLUSIONS: The positive case provided evidence for Sysmex UN's capability to detect atypical cells in urine. The negative cases presented clues that probable vulvovaginal contamination and crowded specimens could be deceptive for Sysmex UN in this particular parameter.


Assuntos
Carcinoma/patologia , Urinálise/instrumentação , Adulto , Idoso , Automação Laboratorial , Carcinoma/urina , Células Epiteliais/patologia , Feminino , Humanos , Leucócitos/patologia , Masculino , Microscopia , Pessoa de Meia-Idade , Urotélio/patologia
14.
Int J Lab Hematol ; 42(1): 28-36, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31769163

RESUMO

INTRODUCTION: Fully-automated coagulation analyzers are key components of a high-throughput central laboratory. The novel Atellica COAG 360 (Siemens Healthineers) is a high-volume coagulation analyzer approved for hemostasis diagnostics. The aim of the study was to evaluate the analytical performance of this coagulation analyzer in a central laboratory. METHODS: Intra (n = 10)- and inter (n = 20)-assay precision of the Atellica COAG 360 was determined using commercially available control samples. Patient samples (n = 74-104) were used for comparison analyses with the Sysmex CS-5100 (Siemens Healthineers). Effects of visual interferences on coagulation testing were assessed and the sample throughput rate of the Atellica COAG 360 was determined. RESULTS: Intra- and inter-assay precision of the Atellica COAG 360 showed coefficient of variations (CVs) < 5% for most of the coagulation parameters comparable to CVs of the Sysmex CS-5100. Passing-Bablok and Bland-Altman analyses revealed high correlation and good agreement between both coagulation analyzers in determination of coagulation parameters. Results of coagulation measurements determined in optically abnormal samples were comparable between the Atellica COAG 360 and the Sysmex CS-5100 and were confirmed by mechanical measurements on a STart Max (Stago Diagnostics) coagulation analyzer. A sample throughput rate of about 190 tests per hour in a routine setting including five coagulation parameters was determined for the Atellica COAG 360 integrated in a total laboratory automation system. CONCLUSION: The Atellica COAG 360 provides high analytical performance as high-throughput analyzer for routine and specific coagulation parameters and is suitable to be connected to a total laboratory automation.


Assuntos
Testes de Coagulação Sanguínea/instrumentação , Coagulação Sanguínea , Adulto , Testes de Coagulação Sanguínea/métodos , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes
15.
Clin Chim Acta ; 511: 298-305, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33096031

RESUMO

BACKGROUND AND AIMS: Polymerase chain reaction-based techniques require expensive equipment for fluorescence detection of the products. However, the measurement of inorganic pyrophosphate (PPi) released during DNA synthesis can be used to quantify target genes without such equipment. Here, we devised a high-sensitivity enzymatic assay for detection of PPi. MATERIALS AND METHODS: In our assay method, PPi was converted to hypoxanthine by hypoxanthine phosphoribosyl transferase. Xanthine dehydrogenase converted the hypoxanthine to uric acid and yielded two molecules of NADH, which in turn reduced Fe3+ to Fe2+ (mediated by 1-methoxy-5-ethylphenazinium ethylsulfate). 2-Nitroso-5-(N-propyl-N-sulfopropylamino) phenol chelated the Fe2+, which resulted in an intensely colored product that could be measured using a biochemical automated analyzer. RESULTS: The assay was able to detect PPi within 10 min. It was linear between 0 and 10 µmol/L PPi, and intra-run and inter-run coefficients of variation were 1%-2%. Other validation tests with a biochemical automated analyzer were satisfactory. The assay could potentially be used to directly quantify samples after isothermal nucleic acid sequence-based amplification of a target gene. CONCLUSION: The method developed here for detection of PPi can be used to measure nucleic acid biomarkers in biological samples in clinical practice using a high-throughput biochemical automated analyzer.


Assuntos
Difosfatos , Replicação de Sequência Autossustentável , Humanos , Técnicas de Amplificação de Ácido Nucleico , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
16.
J Lab Physicians ; 11(1): 29-33, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30983799

RESUMO

INTRODUCTION: Morphologic changes in the size and granularity of leukocytes seen in sepsis could be measured using the volume, conductivity, and scatter (VCS parameters) from the automated hematology analyzers. The objective of this study is to find the clinical usefulness of VCS parameters as possible indicators of sepsis and to determine the effect of treatment on these parameters. METHODS: This observational study was conducted in a tertiary level hospital in India. Hemogram and VCS parameters obtained from LH 750 (Beckman coulter, Fullerton, CA) from 134 proven blood culture-positive cases of sepsis were reviewed on the day of culture positivity (day 0), day 3, and day 7 were analyzed and compared with those of samples from otherwise healthy 100 participants. Statistical analysis of data was done, and cutoff value was established using receiver-operator characteristic curve. RESULTS: Out of 134 culture-positive cases, 55.2% (n = 74) Gram-negative and 44.8% (n = 60) Gram-positive bacteria were isolated. The mean neutrophil volume (MNV) and mean monocyte volume (MMV) were higher in the sepsis group compared to that of the control group (165.43 ± 18.21 vs. 140.59 ± 7.6, P = 0.001 for MNV and 179.8 ± 14.16 vs. 164.54 ± 9.6, P = 0.001 for MMV). A significant decrease in MNV and MMV was observed with the initiation of the treatment. Significant changes in scatter and conductivity parameters were also noticed. A cutoff value of 150.2 for MNV gave a sensitivity and specificity of 79.1% and 95%, respectively, with an area under the curve (AUC) of 92.3%. With a cutoff of 168.3, MMV had a sensitivity of 80.6% and specificity of 77.5%, AUC of 83%. CONCLUSION: VCS parameters such as MNV and MMV can be easily obtained by an automated hematology analyzer and could be used for early detection and therapeutic response in sepsis.

17.
J Vet Intern Med ; 33(1): 167-177, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30511380

RESUMO

BACKGROUND: Microscopic evaluation of urine is inconsistently performed in veterinary clinics. The IDEXX SediVue Dx® Urine Sediment Analyzer (SediVue) recently was introduced for automated analysis of canine and feline urine and may facilitate performance of urinalyses in practice. OBJECTIVE: Compare the performance of the SediVue with manual microscopy for detecting clinically relevant numbers of cells and 2 crystal types. SAMPLES: Five-hundred thirty urine samples (82% canine, 18% feline). METHODS: For SediVue analysis (software versions [SW] 1.0.0.0 and 1.0.1.3), uncentrifuged urine was pipetted into a cartridge. Images were captured and processed using a convolutional neural network algorithm. For manual microscopy, urine was centrifuged to obtain sediment. To determine sensitivity and specificity of the SediVue compared with manual microscopy, thresholds were set at ≥5/high power field (hpf) for red blood cells (RBC) and white blood cells (WBC) and ≥1/hpf for squamous epithelial cells (sqEPI), non-squamous epithelial cells (nsEPI), struvite crystals (STR), and calcium oxalate dihydrate crystals (CaOx Di). RESULTS: The sensitivity of the SediVue (SW1.0.1.3) was 85%-90% for the detection of RBC, WBC, and STR; 75% for CaOx Di; 71% for nsEPI; and 33% for sqEPI. Specificity was 99% for sqEPI and CaOx Di; 87%-90% for RBC, WBC, and nsEPI; and 84% for STR. Compared to SW1.0.0.0, SW1.0.1.3 had increased sensitivity but decreased specificity. Performance was similar for canine versus feline and fresh versus stored urine samples. CONCLUSIONS AND CLINICAL IMPORTANCE: The SediVue exhibits good agreement with manual microscopy for the detection of most formed elements evaluated, but improvement is needed for epithelial cells.


Assuntos
Autoanálise/veterinária , Oxalato de Cálcio/urina , Microscopia/veterinária , Estruvita/urina , Urina/citologia , Algoritmos , Animais , Autoanálise/métodos , Gatos/urina , Cães/urina , Contagem de Eritrócitos/métodos , Contagem de Eritrócitos/veterinária , Contagem de Leucócitos/métodos , Contagem de Leucócitos/veterinária , Microscopia/métodos , Sensibilidade e Especificidade , Software , Urina/química
18.
Pract Lab Med ; 17: e00147, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31799362

RESUMO

OBJECTIVES: The level of glycated hemoglobin A (HbA1C) in blood is the preferred marker for diabetes monitoring and treatment. Here, we evaluate the analytical performance of the Roche Diagnostics Cobas c 513, a stand-alone HbA1C immunoassay analyzer. DESIGN AND METHODS: Performance was assessed with regards to imprecision, accuracy, linearity, method comparison against the Roche Cobas Integra 800 CTS, specimen stability, interference from common hemoglobin variants and hemoglobin F, and throughput. RESULTS: Within-run and between-run precisions were 0.5-0.7 and 0.8-1.3%CV, respectively. An average bias of -1.6% to proficiency survey samples was observed. The c 513 correlated well with the Integra (slope = 0.94, y-intercept = 0.50, and correlation coefficient = 0.998). The effect of hemoglobin variants on this assay was negligible while specimens containing ≥10% HbF demonstrated a negative bias. The c 513 instrument can process up to 340 samples per hour. CONCLUSIONS: The c 513 is a precise, accurate, automated high throughput analyzer for measuring HbA1C in large laboratories.

19.
J Lab Physicians ; 9(1): 1-4, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28042208

RESUMO

BACKGROUND AND OBJECTIVE: With the advent of automated hematology analyzer, the use of traditional microscopy of blood film has become limited. The objective of our study was to determine the percentage of peripheral blood smear review in our institution in the era of automation and to identify reasons of manual review. MATERIALS AND METHODS: This was a prospective audit from January 1, 2015, to January 15, 2015. Consecutive complete blood count (CBC) samples and peripheral smear requests made up the sample size. All age groups and genders were included. CBCs were performed on Sysmex XE-5000. The variables to be analyzed included inpatient and outpatient samples, frequency of peripheral film review, identifying reasons of smear review, and addition of information missed by the automated analyzer. RESULTS: We analyzed 1200 consecutive CBC samples. Peripheral smear was reviewed in 500 (42%) of the cases of which, 241 were inpatient, and 259 were outpatient samples. In 384/500, the findings of hematology analyzer correlated with peripheral smear review. Flags identified included nucleated red blood cells (NRBCs) in 155 (40%), immature white blood cell (WBC) 129 (34%), and atypical lymphocytes 100 (26%). In 23% of the cases, the analyzer missed important findings. The sensitivity of abnormal histogram in our study was 91.3%, while the sensitivity of abnormal parameters was 100%. CONCLUSION: Peripheral smear review was performed in 42% of the cases. The analyzer identified NRBC, immature WBC precursors, and atypical lymphocytes as the most common abnormality. The information correlated in 77% of the cases.

20.
Pract Lab Med ; 4: 50-61, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28856193

RESUMO

BACKGROUND: We compared the diagnostic performances of two newly introduced fully automated multiple allergen simultaneous tests (MAST) analyzers with two conventional MAST assays. METHODS: The serum samples from a total of 53 and 104 patients were tested for food panels and inhalant panels, respectively, in four analyzers including AdvanSure AlloScreen (LG Life Science, Korea), AdvanSure Allostation Smart II (LG Life Science), PROTIA Allergy-Q (ProteomeTech, Korea), and RIDA Allergy Screen (R-Biopharm, Germany). We compared not only the total agreement percentages but also positive propensities among four analyzers. RESULTS: Evaluation of AdvanSure Allostation Smart II as upgraded version of AdvanSure AlloScreen revealed good concordance with total agreement percentages of 93.0% and 92.2% in food and inhalant panel, respectively. Comparisons of AdvanSure Allostation Smart II or PROTIA Allergy-Q with RIDA Allergy Screen also showed good concordance performance with positive propensities of two new analyzers for common allergens (Dermatophagoides farina and Dermatophagoides pteronyssinus). The changes of cut-off level resulted in various total agreement percentage fluctuations among allergens by different analyzers, although current cut-off level of class 2 appeared to be generally suitable. CONCLUSIONS: AdvanSure Allostation Smart II and PROTIA Allergy-Q presented favorable agreement performances with RIDA Allergy Screen, although positive propensities were noticed in common allergens.

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