Comparison of four enzymatic library preparation kits for sequencing Shiga toxin-producing Escherichia coli for surveillance and outbreak detection.

Four enzymatic DNA library preparation kits were compared for sequencing Shiga toxin-producing E. coli. All kits produced high quality sequence data which performed equally well in the downstream analyses for surveillance and outbreak detection. Important differences were noted in the workflow user-friendliness and per sample cost.

Comparison of three qPCR-based commercial tests for detection of periodontal pathogens.

In periodontal practice microbial results of periodontal test kits for identification of key pathogens are an aid in the treatment planning. Information on the performance of commercially available test kits is therefore essential for the clinician. In this retrospective analysis three commercially available qPCR kits for detection and quantification of selected periodontal bacterial species were compared, using 100 clinical samples from patients with untreated periodontitis. The analysis involved two separate comparisons in which kit A (LabOral Diagnostics, The Netherlands) was compared with kit B (Advanced Dental Diagnostics, The Netherlands), and with kit C (OralDent diagnostics, The Netherlands). Analytic procedures for detection and quantification of selected periodontal bacterial species were carried out according to the instructions of the laboratories. Kit A detected target species more often, and absolute numbers of bacterial cells were higher than with kit B. A high degree of similarity was found between the test outcomes by kit A and kit C. All three kits performed satisfactory but small and significant differences exist between kits.

Rapid detection of bacteria in bloodstream infections using a molecular method: a pilot study with a neonatal diagnostic kit.

Neonatal sepsis is a life-threatening condition and its early diagnosis is crucial for infant survival. Identifying responsible pathogens is a key step. Blood culture (BC) is the gold standard, but more rapid and specific diagnostic methods are needed. We evaluated the reliability and utility of 3 h turnaround time diagnostic molecular kit, "EuSepScreen lattanti "CE IVD marked, (EuSepScreen lattanti, Eurospital Spa Trieste, Italy) specifically targeted to detect 4 pathogens in neonatal sepsis: Klebsiella pneumoniae (KP), Escherichia coli (EC), Streptococcus agalactiae (GBS), and Lysteria monocytogenes. We evaluated 69 neonates, 40 full term and 29 preterm infants, with suspected bloodstream infection, who, overall the routine clinical procedures, were tested using the molecular kit. Kit results were compared to BC outcomes. Nineteen cases for early onset sepsis (EOS) were evaluated, 2 of them resulted positive to a molecular kit and to BC (both for GBS and EC). In the 50 cases of suspected late onset sepsis (LOS), 7 infants reported positive and coincident results to both the methods, in 3 further cases the molecular kit identified pathogens (EC) in neonates with negative BC result; in 10 cases BC revealed etiological pathogens exceeding the molecular kit possibility of identification. In case of EOS, results of the molecular kit were coincident to these of BC, but available in 3 h turnaround time, which is an advantage, so the kit may actually be an "add-on tool" for EOS, with reference to EC and GBS, but a larger study with a greater number of EOS cases are needed to validate its usefulness in the NICU. Regarding LOS the restricted panel of identifiable microorganisms failed to provide timely information for sepsis diagnosis, highlighting the need of enlarged number microorganisms for the diagnosis of LOS.Trial registration number: NCT03884894.

Performance evaluation of three rapid antigen tests for the diagnosis of group A Streptococci.

OBJECTIVE: To compare the diagnostic performance of three rapid antigen detection tests (RADTs) for group A Streptococcus (GAS). DESIGN: A hospital-based, cross-sectional, retrospective study. SETTING: A comparative study of rapid diagnostic tests for GAS using clinical specimens in a single institute. PARTICIPANTS: 225 children in the outpatient clinics ofKorea University Guro Hospitalwith suspicious symptoms were subjected to throat swab sampling. A dual-swab applicator was used. Samples were stored at below -70°C in a 10 mL transport tube containing 1 mL liquid Stuart's transport medium. OUTCOME MEASURES: All tests were performed in the laboratory by trained clinical laboratory scientists. Sensitivity, specificity, accuracy and kappa index of three RADTs were compared with the reference PCR test and culture results. RESULTS: Of the 225 patients suspected of having GAS, 67 and 90 were positive for GAS in the culture and PCR tests, respectively. Compared with the reference culture, the sensitivity for GAS was 92.5% (CI 83.4 to 97.5), 71.6% (CI 59.3 to 81.9) and 74.63% (CI 62.5 to 84.4) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively, and the specificity was 97.0% (CI 93.1 to 99.0), 94.6% (CI 90.1 to 97.5) and 92.9% (CI 87.8 to 96.2) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively. Compared with the reference GAS real-time PCR, the sensitivity was 73.3% (CI 62.9 to 82.1), 63.3% (CI 52.5 to 73.2) and 67.8% (CI 57.1 to 77.2) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively, and the specificity was 99.3% (CI 95.9 to 99.9), 100.0% (CI 97.3 to 100.0) and 99.3% (CI 95.9 to 99.9) for careUS Strep A Plus, SD Bioline and BD Veritor, respectively. CONCLUSIONS: The careUS Strep A Plus is a useful test that showed highly comparable results with those of the culture test and superior performances among the three RADTs. The use of RADTs should be encouraged to provide acceptable and fast results using simple equipment.

High Efficacy of Rapid Urine Test for Diagnosis of Helicobacter pylori Infection in Thai People

Background: Accurate diagnosis of Helicobacter pylori (H. pylori) infection plays an important role in further effective treatment. Rapid urine test (RAPIRUN) is a test developed for qualitative detection of urine H. Pylori antibody and use for determine the sensitivity, specificity and accuracy. However, the test needs validation in Thai population before using in clinical practice. Objective: This study aimed to compare performance of different diagnostic tests on H. pylori detection in Thai population. Methods: Total of 94 patients with dyspepsia who referred to Thammasat University Hospital, Pathumthani, Thailand, between December 2012 and April 2013 were enrolled in this study. All patients underwent gastroscopy. Then, 3 biopsies at antrum were taken for H. pylori diagnosis. including rapid urease test (Pronto Dry, Eisai, Thailand), H. pylori culture, and histopathology. Urine samples were also collected at the same time for rapid urine test (RAPIRUN H. pylori Antibody, Otsuka Pharmaceutical Co., Ltd.). Patients were diagnosed with H. pylori-positive if their culture or rapid urease tests plus histopathology yielded positive results. Results: Total of 29 patients (30.9%) were infected with H. pylori. Prevalence of H. pylori infection by rapid urease test, histopathology, culture and rapid urine test were 25.5%, 28.7%, 29.8%, and 32.9% respectively. We observed that rapid urease test, histopathology, culture, and rapid urine test had sensitivity of 82.8%, 93.1%, 93.1% and 86.2%; specificity of 100%, 100%, 100%, and 90.8%; and accuracy of 95.7%, 97.9%, 97.9%, and 89.4%, respectively. Conclusion: Rapid urine test (RAPIRUN) provided a reliable result for diagnosis of H. pylori infection. Furthermore, this rapid urine test demonstrated high accuracy, reliable, safe handle and easy to use. We suggested rapid urine test for diagnosis of H. pylori infection in Thai population since we found it less invasive and with higher reliable efficacy.

Rapid antigen diagnostic testing for the diagnosis of group A beta-haemolytic streptococci pharyngitis.

Background: It is difficult to make a diagnosis of group A beta-haemolytic streptococci (GABHS) pharyngitis solely on clinical findings. The McIssac scoring system has been recommended as a reliable clinical tool for diagnosis. The rapid antigen detection test (RADT) has been shown to considerably increase the number of patients who are appropriately treated for streptococcal pharyngitis, compared with the use of traditional throat cultures. It also reduces the time to start treatment. We evaluated the diagnostic utility of RADT in comparison with throat swab culture. Methods: Using the McIssac scoring system, RADT and throat swab cultures in those with a McIssac score of 3 or more, we evaluated 165 children (aged 2-15 years) with a clinical diagnosis of pharyngitis. Results: GABHS pharyngitis was confirmed in 41 (24.8%) by throat swab culture and RADT was positive in 39(23.6%). Only in 2 (4.9%) children, RADT was negative but throat swab was positive. The sensitivity of RADT was 89.7% and specificity was 98.4% with a positive predictive value of 94.6%, negative predictive value of 96.9% and diagnostic accuracy of 96.4%. Conclusion: RADT performed was observed to have high sensitivity and sensitivity for the diagnosis of GABHS pharyngitis in contrast to an earlier report from India. Our observations suggest that using RADT as a point-of-care test is reliable and cost-effective and needs to be propagated in Indian settings where facilities for throat swab culture are not routinely available and also because clinical diagnosis based on scoring systems are comparatively less reliable.

Rapid Diagnostic Tests in Childhood Infections.

Presumptive treatment of infections often results in irrational antimicrobial use resulting in detrimental spread of drug resistance and untoward side effects. A rapid diagnostic test (RDT) is a test that delivers a result earlier than conventional testing methods employed in the past to identify the offending microorganism. RDTs help in early definitive therapy, reduction in hospital stay and cost, and in degree of morbidity and mortality associated with the infection. To select a proper RDT, one should consider how specific and sensitive the test is. Most RDTs gives a qualitative result not quantitative; hence disease severity, monitoring of the disease, prognostication and therapeutic efficacy cannot be assessed. A RDT should be easy to perform, should not require sophisticated machines, and kits should be stable in extremes of temperature. RDTs may be of immense help in remote places where conventional diagnostic facilities are unavailable or lack quality. RDTs hold promise of reasonable diagnostic accuracy if done in a optimal clinical background. They should never be ordered as a shotgun approach to exclude all possible infections but should be used judiciously with appropriate interpretation.

Influence of the microbiological component of Cariogram® for evaluating the risk of caries in children.

OBJECTIVE: To compare the risk for caries in children as determined by Cariogram® software (CS; Stockholm, Sweden) with and without its microbiological component and by a form based on Cariogram® (FBC). METHODS: Children (n = 28) aged 3-9 years were included. Data were collected clinically and from anamnesis. The salivary levels of Streptococcus mutans (SM) were evaluated. A linear regression model was used to determine which variables were predictive for each type of risk analysis. Caries risk was the dependent variable and the independent variables were caries experience, related disease, plaque amount, diet frequency, salivary levels of SM, fluoride sources and clinical judgment. A paired Student t-test was used for the following comparisons: (a) CS with and without SM; (b) CS without SM and FBC; (c) CS with SM and FBC. RESULTS: The mean dmft/DMFT was 5.56 ± 2.51. There was no difference between the methods (p < .05). Regardless of caries risk, the children presented the same levels of SM (p = .889). Caries experience, plaque amount, diet frequency and fluoride sources were predictors of caries risk in all assessment methods. Clinical judgment was a significant predictor in CS. CONCLUSIONS: Caries experience, plaque amount, diet frequency and fluoride sources are valuable predictors of caries risk; microbiological tests are not necessary for evaluating caries risk in children, which can be assessed similarly by CS without SM and FBC.

[ON DEVELOPMENT OF TOOLS OF IMMUNE DIAGNOSTIC OF INFECTIOUS DISEASES: PROBLEMS OF DIAGNOSTIC IN VIVO AND IN VITRO].

The article considers a number of problematic issues concerning development of effective means of immune diagnostic of infectious diseases of bacterial and mycotic etiology related to approaches of choosing appropriate diagnostic targets.

[THE MOLECULAR TECHNIQUES OF DIAGNOSTIC OF GINGIVITIS AND PERIODONTITIS IN HIV-INFECTED PATIENTS].

The examination was carried out in the Moscow clinical infectious hospital No 2 concerning 102 patients with verified diagnosis "AIDS-infection" and seropositive according results of detection of anti-HIV-antibodies in blood serum. The study was organized to analyze rate ofcolonization of gums with virulent anaerobic bacteria in HIV-infected (polymerase chain reaction) and antibodies to HIV in gingival fluid (enzyme-linked immunosorbent assay). It is established that in HIV-infected patients, in scrape from gingival sulcus dominate anaerobic bacteria P. gigngivalis and A. ctinomycetemcomitans and in case of periodontitis--P. gingivalis and T. forsythia. The received data permits recommending the test-system "Multident-5" for polymerase chain reaction diagnostic. The reagents kit "Calypte®HIV-1/2"--for enzyme-linked immunosorbent assay gingival fluid. The results of polymerase chain reaction and enzyme-linked immunosorbent assay have no impact of concomitant stomatological (periodontitis, gingivitis) and somatic pathology.

Stool metatranscriptomics: A technical guideline for mRNA stabilisation and isolation.

BACKGROUND: The complex microbiome of the gut has an enormous impact on human health. Analysis of the transcriptional activity of microorganisms through mRNA sequencing (metatranscriptomics) opens a completely new window into their activity in vivo, but it is highly challenging due to numerous technical and bioinformatical obstacles. Here we present an optimized pipeline for extraction of high quality mRNA from stool samples. RESULTS: Comparison of three commercially available RNA extraction kits with the method of Zoetendal revealed that the Powermicrobiome Kit (MoBio) performed best with respect to RNA yield and purity. Next, the influence of the stabilization reagent during sample storage for up to 15 days was studied. RIN analysis and qRT-PCR of spiked-in and indigenous genes revealed that RNA Later preserved mRNA integrity most efficiently, while samples conserved in RNA Protect showed substantial mRNA decay. Using the optimized pipeline developed here, recovery rates for spiked-in E.coli cells expressing fluorescing proteins were 8.7-9.7% for SuperfolderGFP and 14.7-17.8% for mCherry. The mRNA of stabilized stool samples as well as of snap-frozen controls was sequenced with Illumina Hiseq, yielding on average 74 million reads per sample. PCoA analysis, taxonomic classification using Kraken and functional classification using bwa showed that the transcriptomes of samples conserved in RNA Later were unchanged for up to 6 days even at room temperature, while RNA Protect was inefficient for storage durations exceeding 24 h. However, our data indicate that RNA Later introduces a bias which is then maintained throughout storage, while RNA Protect conserved samples are initially more similar to the snap frozen controls. RNA Later conserved samples had a reduced abundance of e.g. Prevotellaceae transcripts and were depleted for e.g. COG category "Carbohydrate transport and metabolism". CONCLUSION: Since the overall similarity between all stool transcriptional profiles studied here was >0.92, these differences are unlikely to affect global comparisons, but should be taken into account when rare but critically important members of the stool microbiome are being studied.

The validation of the NH Immunochromato O157 test kit.

NH Immunochromato O157 is an immunochromatographic test for detection of Escherichia coli O157:H7 and O157:NM in food. It enables simple and rapid testing for the target organism after 18-24 h enrichment. In inclusivity and exclusivity testing, all 50 O157:H7 strains and 15 O157:NM strains tested positive, while all 33 exclusivity strains yielded negative results. Taken together, all 98 strains tested in inclusivity/exclusivity testing were identified correctly. NH Immunochromato O157 method was compared to U.S. Department of Agriculture Food Safety and Inspection Service Microbiology Laboratory Guidebook, Chapter 5.08, reference method for detection of E. coli O157:H7 in 25 g of raw ground beef. The performance of both methods was revealed to be statistically equivalent. Autoclaved and non-autoclaved sample enrichments yielded the same results, showing sterilization is not mandatory for testing with NH Immunochromato O157. The results of the robustness study were not statistically different in all conditions, suggesting that NH Immunochromato produce reliable results under various conditions. However, the users are recommended to follow the instruction when applying sample to the test strip, because a smaller sample volume may produce invalid result.

Vivione Bioscience RAPID-B(®) E. coli O157 test kit and non-O157 STEC test kit evaluation.

RAPID-B(®) is a high performance, integrated microbiology/infectious disease diagnostic system. The system uses hardware and software that are specifically designed for optimal detection using custom, immuno-based reagents designed to react to cell surface antigens of the target bacteria. The Vivione Bioscience RAPID-B Escherichia coli O157 and non-O157 Shiga toxin-producing E. coli (STEC) kits were validated alongside the U.S. Department of Agriculture, Food Safety and Inspection Service (FSIS), Microbiology Laboratory Guidebook (MLG) 5.07 (for E. coli O157) and FSIS MLG 5B.04 (for non-O157 STEC) reference methods for the detection of E. coli O157 and STEC. The matrixes, ground beef and beef trim, were inoculated with appropriate CFU/test portion of E. coli O157 and STEC so as to generate fractional positives results, 5 to 15 positives out of 20 inoculated samples. Samples were enriched in prewarmed Brain Heart Infusion broth at 42 ± 1°C for 6.5-7.5 h or 8.5-9.5 h depending on the sample size. All samples were confirmed using the MLG reference method, regardless of initial screen result. The RAPID-B test methods were statistically equivalent to the reference method for the detection of E. coli O157 and STEC in all tested samples. Inclusivity and exclusivity testing of the RAPID-B methods showed 100% specificity for both kits. Finally, the RAPID-B test methods were shown to be robust when variations were applied to enrichment time, broth temperature, and vortexing time.

Evaluation of a rapid diagnostic test for yaws infection in a community surveillance setting.

Yaws is a non-venereal treponemal infection caused by Treponema pallidum ssp. pertenue. The WHO has launched a worldwide control programme, which aims to eradicate yaws by 2020. The development of a rapid diagnostic test (RDT) for serological diagnosis in the isolated communities affected by yaws is a key requirement for the successful implementation of the WHO strategy. We conducted a study to evaluate the utility of the DPP test in screening for yaws, utilizing samples collected as part of a community prevalence survey conducted in the Solomon Islands. 415 serum samples were tested using both traditional syphilis serology (TPPA and quantitative RPR) and the Chembio DPP Syphilis Screen and Confirm RDT. We calculated the sensitivity and specificity of the RDT as compared to gold standard serology. The sensitivity of the RDT against TPPA was 58.5% and the specificity was 97.6%. The sensitivity of the RDT against RPR was 41.7% and the specificity was 95.2%. The sensitivity of the DPP was strongly related to the RPR titre with a sensitivity of 92.0% for an RPR titre of >1/16. Wider access to DPP testing would improve our understanding of worldwide yaws case reporting and the test may play a key role in assessing patients presenting with yaws like lesions in a post-mass drug administration (MDA) setting.

Microorganisms in respiratory tract of patients diagnosed with atypical pneumonia: results of a research based on the use of reverse transcription polymerase chain reaction (RT-PCR) DNA microarray method and enzyme-linked immunosorbent assay.

BACKGROUND: Numerous molecular-based tests were applied for the laboratory-based diagnosis of viruses. In this cross-sectional case control study, in addition to bacteria, we aimed to determine respiratory viruses using, for the first time in our country, the Reverse Transcription PCR DNA Microarray method, and we also aimed to evaluate its diagnostic performance. METHODS: Respiratory viruses were investigated from nasopharyngeal swabs of 76 patients diagnosed with atypical pneumonia and 64 healthy controls using the CLART Pneumovir (Genomica, Spain) kit and from 10 mL blood samples of the same subjects. M. pneumoniae IgM was detected by ELISA and L. pneumophila IgM and C. pneumoniae IgM by indirect immunofluorescence. Person's chi-square test was used for statistical analysis. RESULTS: Our results showed that the specificity (100%) and the positive predictive value (100%) of the CLART Pneumovir kit were high, but its sensitivity (53%), its negative predictive value (64%), and its kappa value (50%) were low. Parainfluenza Virus type 3 and M. pneumoniae were found alone or together as the most common microorganisms while no cases of human bocavirus, adenovirus, rhinovirus, or coronavirus were detected. CONCLUSIONS: Our results demonstrated that, during the study period, most of our patients had atypical pneumonia due to Parainfluenza Virus type 3 and M. pneumoniae co-infection.

Comparison of a new microbiological assay with a standard high-performance liquid chromatographic method for determination of vitamin B6 in serum.

BACKGROUND: A high-performance liquid chromatographic (HPLC) assay for vitamin B6 in human serum was compared with a novel microbiological assay (ID-Vit) that uses microtitre plates precoated with a specific microorganism, thus avoiding numerous problems associated with the use of stock cultures utilized by common other microbial assay mit B6. METHODS: Data obtained using HPLC were compared with 1D-Vit results in 170 healthy individuals and in 68 patients with coronary artery disease (CAD, 37 with acute coronary syndrome [ACS], 31 with stable CAD). Regression and Bland-Altman analysis were performed. Homocysteine in CAD patients was measured by HPLC. RESULTS: The ID-Vit assay correlated well with the HPLC assay (Pearson's r = 0.89 [p < 0.0001] in healthy and 0.82 [p < 0.001] in CAD individuals). Bland-Altman analyses revealed good agreement between the results of both methods in both cohorts, with > or = 95% of all values grouping within the lines of agreement. In CAD patients, mean homocysteine values did not differ between stable CAD and ACS and were normal. Thirty-seven percent of CAD patients had estimated glomerular filtration rates (GFR) below 60 mL/min/1.73m2. GFR correlated inversely with homocysteine levels (r = -0.80, p < 0.001) whereas neither HPLC nor ID-Vit values for B6 did. CONCLUSIONS: ID-Vit assay and the HPLC standard are in very good agreement. The new assay can easily be automated and is less laborious than common microbiological assays. The lack of correlation between B6 vitamin and homocysteine can be accounted for by the fact that mean vitamin B6 in our CAD patients was in the normal range and that a relevant percentage of patients had chronic renal disease.

ESwab as an optional collection device for use with the Affirm VPIII microbial test system.

The ESwab collection device was compared to the collection swab provided as part of the Affirm VPIII microbial identification test kit for testing vaginal specimens with the Affirm test system. There was excellent agreement between the two sampling devices for Candida spp., Gardnerella vaginalis, and Trichomonas vaginalis.

Evaluación de las características funcionales del juego de reactivos VDRL Plus / Evaluation of the functional characteristics of the set of reagents called VDRL Plus

Introducción: la prueba de VDRL (venereal disease research laboratories) es una técnica no treponémica de microfloculación en lámina para la detección cualitativa y semicuantitativa de reaginas plasmáticas. El VDRL Plus es un juego de reactivos que contiene una suspensión antigénica estabilizada (no alcohólica), basada en una mezcla de cardiolipina, colesterol y lecitina en tampón fosfato. Objetivo: determinar un conjunto de parámetros funcionales que caracterizan el desempeño diagnóstico o clínico del juego de reactivo VDRL Plus producido en Centro de Isótopos (CENTIS). Métodos: los parámetros del desempeño diagnóstico evaluados fueron: sensibilidad y especificidad diagnóstica, valores predictivos positivo y negativo, razón de verosimilitud positiva y negativa. Se determinaron además los índices de Youden y de concordancia Kappa. Se emplearon como métodos de referencia TPHA (Treponema pallidum hemagglutination) y RPR (rapid plasma reagin)-carbón producidos en el CENTIS. Se utilizaron muestras de sueros obtenidas en diferentes instituciones de salud de La Habana y el estudio se realizó con dos lotes del producto. Resultados: para los dos lotes evaluados se obtuvieron valores de sensibilidad de 100 porciento y de especificidad diagnóstica de 81 y 84 porciento. Los valores predictivos positivos resultaron de 71 y 75 porciento, y los negativos de 100 porciento. Por su parte, las razones de verosimilitud negativas fueron de 0 porciento y las positivas de 5,3 y 6,3 porciento, para cada lote estudiado. Los índices de Youden obtenidos (0,84 y 0,81) y la concordancia expresada mediante Kappa muestran que existe una adecuada correlación entre los resultados con el método en evaluación y los de referencia. Conclusiones: las características funcionales evaluadas evidencian que el diagnosticador VDRL Plus es apto para el uso previsto y que estas son consistentes entre los lotes estudiados

Introduction: the VDRL test (venereal disease research laboratories) is a no-treponemal slide microaglutination test for the qualitative and semi-quantitative detection of plasma reagins in human serum. The VDRL Plus contains non alcoholic stabilized antigen suspension based in cardiolipin, lecithin and cholesterol in phosphate buffer. Objective: to determine a group of functional parameters in the diagnostic or clinical performance of the VDRL Plus set of reagents produced by the Center of Isotopes (CENTIS). Methods: several parameters, such as, sensitivity, specificity, positive and negative predictive values and positive and negative likelihood ratios were evaluated. Likewised, Youden and Kappa indexes were calculated. Two references methods were employed, that is, TPHA (Treponema pallidum hemagglutination) and RPR-Carbon (rapid plasma reagin)-carbon, both from CENTIS. Serum samples were collected from several health centers in Havana city. Two different product batches were evaluated. Results: the sensitivity value for both evaluated batches was 100 percent and the specificity was 81 and 84 percent. The positives predictive values were 71 and 75 percent and negative predictive value was 100 percent. The positive likelihood ration were 5.3 and 6,3 percent respectively and negative likelihood ration was 0 percent for both batches. The Youden indexes obtained (0.84 and 0.81) and Kappa's indexes showed that there was an adequate correlation between the results obtained and the evaluation and reference methods. Conclusions: the evaluated functional characteristics showed that they are consistent among studied batches and that the VDRL Plus assay is suitable for the intended use

An adhesion molecule-based colloidal gold immunochromatography assay strip for rapidly and specifically detecting chicken antibodies against Mycoplasma gallisepticum.

The fragment of the VlhA1.2 gene was cloned from a Mycoplasma gallisepticum (MG) DNA library by serial PCRs after the same-sense mutagenesis of three TGA codons encoding tryptophan (Trp). Following transforming the generated plasmid of pKG-VlhA1.2, the recombinant VlhA1.2-GST fusion protein of 92kDa was induced and recognized by anti-MG sera. After GST-affinity chromatographic purification, the VlhA-based colloidal gold immunochromatography assay (GICA) strips were generated. The GICA strips specifically detected anti-MG antibodies, but not antibodies against Mycoplasma synoviae and other positive sera against non-MG pathogens tested. The GICA strips were 128-fold more sensitive to detect anti-MG antibodies, as compared with traditional serological methods and were stored at 4° C for 15 months without loss of their sensitivity and specificity. Analysis of sample revealed that, the GICA strips were highly sensitive, specific and stable for the on-site surveillance of MG infections by unskilled users.