Reference Test Research Articles

Accuracy of rapid lateral flow immunoassays for human leptospirosis diagnosis: A systematic review and meta-analysis.

In the last two decades, several rapid lateral flow immunoassays (LFIs) for the diagnosis of human leptospirosis were developed and commercialized. However, the accuracy and reliability of these LFIs are not well understood. In this study, we aimed to evaluate the accuracy of leptospirosis LFIs as well as the factors affecting the test efficiency using systematic review and meta-analysis. Original articles reporting the accuracy of human leptospirosis LFIs against microagglutination tests (MAT) or immunofluorescent assays (IFA) were searched from PubMed, Embase, and Scopus, and selected as per pre-set inclusion and exclusion criteria. A total of 49 data entries extracted from 24 eligible records published between 2003 and 2023 were included for meta-analysis. A meta-analysis was performed using STATA. The quality of the included studies was assessed according to the revised QUADAS-2. Only nine studies (32.1%) were considered to have a low risk of bias and no concern for applicability. Pooled sensitivity and specificity were calculated to be 68% (95% confidence interval, CI: 57-78) and 93% (95% CI: 90-95), respectively. However, the ranges of sensitivity (3.6 - 100%) and specificity (53.5 - 100%) of individual entries are dramatically broad, possibly due to the heterogeneity found in both study designs and LFIs themselves. Subgroup analysis demonstrated that IgM detection has better sensitivity than detection of IgG alone. Moreover, the test performance seems to be unaffected by samples from different phases of infection. The pooled specificity of LFIs observed is somewhat acceptable, but the pooled sensitivity is low. These results, however, must be interpreted with caution because of substantial heterogeneity. Further evaluations of the LFIs with well-standardized design and reference test will be needed for a greater understanding of the test performance. Additionally, IgM detection type should be employed when leptospirosis LFIs are developed in the future.

Targeted sequencing from cerebrospinal fluid for rapid identification of drug-resistant tuberculous meningitis.

Mortality from tuberculous meningitis (TBM) remains around 30%, with most deaths occurring within 2 months of starting treatment. Mortality from drug-resistant strains is higher still, making early detection of drug resistance (DR) essential. Targeted next-generation sequencing (tNGS) produces high read depths, allowing the detection of DR-associated alleles with low frequencies. We applied Deeplex Myc-TB-a tNGS assay-to cerebrospinal fluid (CSF) samples from 72 adults with microbiologically confirmed TBM and compared its genomic drug susceptibility predictions to a composite reference standard of phenotypic susceptibility testing (pDST) and whole genome sequencing, as well as to clinical outcomes. Deeplex detected Mycobacterium tuberculosis complex DNA in 24/72 (33.3%) CSF samples and generated full DR reports for 22/24 (91.7%). The read depth generated by Deeplex correlated with semi-quantitative results from MTB/RIF Xpert. Alleles with <20% frequency were seen at canonical loci associated with first-line DR. Disregarding these low-frequency alleles, Deeplex had 100% concordance with the composite reference standard for all drugs except pyrazinamide and streptomycin. Three patients had positive CSF cultures after 30 days of treatment; reference tests and Deeplex identified isoniazid resistance in two, and Deeplex alone identified low-frequency rifampin resistance alleles in one. Five patients died, of whom one had pDST-identified pyrazinamide resistance. tNGS on CSF can rapidly and accurately detect drug-resistant TBM, but its application is limited to those with higher bacterial loads. In those with lower bacterial burdens, alternative approaches need to be developed for both diagnosis and resistance detection.

Comparison of an Enzyme Linked-Immunosorbent Assay and a Chemiluminescent Immunoassay with an Immunofluorescence Assay for Detection of Phase II IgM and IgG Antibodies to Coxiella burnetii.

In this study, we have compared the detection of IgM and IgG against C. burnetii phase II of an enzyme-linked immunosorbent assay (ELISA) (Euroimmun) and a chemiluminescent immunoassay (CLIA) (VIRCLIA, Vircell). In addition, an indirect immunofluorescence assay (IFA) was used as a reference test. One hundred forty-eight sera were used for IgG evaluation, and eighty-eight for IgM. The sensitivity of ELISA and CLIA in detecting phase II IgM was excellent. On the other hand, the CLIA IgM showed better specificity than the ELISA IgM. As for phase II IgG, the specificity of ELISA and CLIA was similar, while the ELISA technique showed a higher sensitivity. In conclusion, the best system to detect phase II IgM antibodies against C. burnetii is the CLIA from Vircell, which is characterized by high sensitivity and specificity. For the detection of phase II IgG, the Euroimmun ELISA and Vircell CLIA assays are suitable for the determination of this marker in the laboratory, although the IgG ELISA has greater sensitivity.

Diagnostic tests for human Schistosoma mansoni and Schistosoma haematobium infection: a systematic review and meta-analysis

Accurate diagnosis is pivotal for implementing strategies for surveillance, control, and elimination of schistosomiasis. Despite their low sensitivity in low-endemicity areas, microscopy-based urine filtration and the Kato-Katz technique are considered as reference diagnostic tests for Schistosoma haematobium and Schistosoma mansoni infections, respectively. We aimed to collate all available evidence on the accuracy of other proposed diagnostic techniques. In this systematic review and meta-analysis, we searched PubMed, Embase, the Cochrane Library, and LILACS for studies published from database inception to Dec 31, 2022, investigating the sensitivity and specificity of diagnostic tests for S haematobium and S mansoni infections against Kato-Katz thick smears or urine microscopy (reference tests) involving adults (aged ≥18 years), school-aged children (aged 7 to 18 years), or preschool-aged children (aged 1 month to 7 years). We extracted raw data on true positives, true negatives, false positives, and false negatives for the diagnostic tests and data on the number of participants, study authors, publication year, journal, study design, participants' age and sex, prevalence of Schistosoma infection, and treatment status. To account for imperfect reference tests, we used a hierarchical Bayesian latent class meta-analysis to model test accuracy. Overall, we included 121 studies, assessing 28 different diagnostic techniques. Most studies (103 [85%] of 121) were done in Africa, 14 (12%) in South America, one (1%) in Asia, and one (1%) in an unknown country. Compared with the reference test, Kato-Katz thick smears, circulating cathodic antigen urine cassette assay version 1 (CCA1, 36 test comparisons) had excellent sensitivity (95% [95% credible interval 88-99]) and reasonable specificity (74% [63-83]) for S mansoni. ELISA-based tests had a performance comparable to circulating cathodic antigen, but there were few available test comparisons. For S haematobium, proteinuria (42 test comparisons, sensitivity 73% [62-82]; specificity 94% [89-98]) and haematuria (75 test comparisons, sensitivity 85% [80-90]; specificity 96% [92-99]) reagent strips showed high specificity, with haematuria reagent strips having better sensitivity. Despite limited data, nucleic acid amplification tests (NAATs; eg, PCR or loop-mediated isothermal amplification [LAMP]) showed promising results with sensitivity estimates above 90%. We found an unclear risk of bias of about 70% in the use of the reference or index tests and of 50% in patient selection. All analyses showed substantial heterogeneity (I2>80%). Although NAATs and immunological diagnostics show promise, the limited information available precludes drawing definitive conclusions. Additional research on diagnostic accuracy and cost-effectiveness is needed before the replacement of conventional tests can be considered. WHO and Luxembourg Institute of Health.

Diagnosis of human brucellosis: Systematic review and meta-analysis.

Brucellosis, a widely spread zoonotic disease, poses significant diagnostic challenges due to its non-specific symptoms and underreporting. Timely and accurate diagnosis is crucial for effective patient management and public health control. However, a comprehensive comparative review of available diagnostic tests is lacking. This systematic review addressed the following question: 'What is the accuracy of the available tests to confirm human brucellosis?' Two independent reviewers examined articles published up to January 2023. The review included original studies reporting symptomatic patients with brucellosis suspicion, through any index test, with sensitivity and/or specificity as outcomes. As exclusion criteria were considered: sample size smaller than 10 patients, studies focusing on complicated brucellosis, and those lacking essential information about index or comparator tests. Sensitivity and specificity were assessed, with consideration for the index test, and 'culture' and 'culture and standard tube agglutination test (SAT)' were used as reference standards. Bias assessment and certainty of evidence were carried out using the QUADAS-2 and GRADE tools, respectively. A total of 38 studies reporting diagnostic test performance for human brucellosis were included. However, the evidence available is limited, and significant variability was observed among studies. Regarding the reference test, culture and/or SAT are deemed more appropriate than culture alone. Rose Bengal, IgG/IgM ELISA, and PCR exhibited equally high performances, indicating superior overall diagnostic accuracy, with very low certainty of the evidence. This systematic review underscores the potential of the Rose Bengal test, IgG/IgM ELISA, and PCR as promising diagnostic tools for brucellosis. However, the successful implementation and recommendations for their use should consider the local context and available resources. The findings highlight the pressing need for standardization, improved reporting, and ongoing advancements in test development to enhance the accuracy and accessibility of brucellosis diagnosis.

Diagnostic accuracy of magnetically guided capsule endoscopy with a detachable string for detecting oesophagogastric varices in adults with cirrhosis: prospective multicentre study

ObjectiveTo evaluate the diagnostic accuracy and safety of using magnetically guided capsule endoscopy with a detachable string (ds-MCE) for detecting and grading oesophagogastric varices in adults with cirrhosis.DesignProspective multicentre diagnostic...

Comparative evaluation of lateral flow assays to diagnose chronic Trypanosoma cruzi infection in Bolivia.

Bolivia has the highest incidence of Chagas disease (CD) worldwide. Caused by the parasite Trypanasoma cruzi, CD is generally a chronic condition. Diagnosis is logistically and financially challenging, requiring at least two different laboratory-based serological tests. Many CD cases are missed; in Bolivia it is estimated just 6% of individuals chronically infected with T. cruzi get diagnosed. Achieving control on the way to elimination of CD requires a radical simplification of the current CD testing pathways, to overcome the barriers to accessing CD treatment. We aimed to generate unbiased performance data of lateral flow assays (LFAs) for T. cruzi infection in Bolivia, to evaluate their usefulness for improving T. cruzi diagnosis rates in a precise and efficient manner. This retrospective, laboratory-based, diagnostic evaluation study sought to estimate the sensitivity/specificity of 10 commercially available LFAs for T. cruzi, using the current CD diagnostic algorithm employed in Bolivia as the reference test method. All tests were blinded at the study site and performed by three operators. In total, 470 serum samples were tested, including 221 and 249 characterized as CD-positive/-negative, respectively. The LFAs were scored according to their relative importance using a decision-tree-based algorithm, with the mean decrease in Gini index as the scoring metric. The estimates of sensitivities ranged from 62.2-97.7% (95% confidence interval (CI) lower bound 55.0-94.7%); for specificities the range was 78.6-100% (95% CI lower bound 72.0-97.5%); 5/10 and 6/10 tests had sensitivity >90% and specificity >95%, respectively. Four LFAs showed high values of both sensitivity (93-95%) and specificity (97-99%). The agreement between 6 LFAs and the reference tests was almost perfect (Kappa 0.83-0.94). Most LFAs evaluated thus showed performances comparable with current laboratory-based diagnostic methods.

Clinical evaluation of a modified SARS-CoV-2 rapid molecular assay, ID NOW ™ COVID-19 2.0

In the diagnosis of coronavirus disease 2019 (COVID-19), several types of instruments and reagents for SARS-CoV-2 nucleic acid testing have been introduced to meet clinical needs. We evaluated the clinical performances of ID NOW™ COVID-19 2.0 (ID NOW™ 2.0), which is capable of detecting SARS-CoV-2 within 12 min as part of point-of-care testing (POCT). Patients who displayed COVID-19 related symptoms, and who were tested for screening purposes, were recruited to this study. Two nasopharyngeal swabs were collected and tested using the ID NOW™ 2.0 test. Reference testing was performed using the cobas 8800 or 6800 (reagents: cobas SARS-CoV-2 and Flu A/B). A total of 38 samples and 46 samples were tested positive and negative, respectively, by the reference test. The ID NOW™ 2.0 showed a sensitivity of 94.7% (95% CI: 82.3–99.4) and a specificity of 100% (95% CI: 92.3–100). Samples that were positive by reference testing had cycle threshold (Ct) values ranging from 11.90 to 35.41. Among these reference positive samples, two samples were negative by ID NOW™ 2.0 with Ct values of 35.25 and 35.41. For samples with Ct values < 35, the sensitivity of ID NOW™ 2.0 was 100%. In Japan, the restrictions related to COVID-19 have been relaxed, however the COVID-19 epidemic still continues. ID NOW™ 2.0 is expected to be used as a rapid and reliable alternative to laboratory-based RT-PCR methods.

Single-cell operando SOC and SOH diagnosis in a 24 V lithium iron phosphate battery with a voltage-controlled model

Batteries typically consist of multiple individual cells connected in series. Here we demonstrate single-cell state of charge (SOC) and state of health (SOH) diagnosis in a 24 V class lithium-ion battery. To this goal, we introduce and apply a novel, highly efficient algorithm based on a voltage-controlled model (VCM). The battery, consisting of eight single cells, is cycled over a duration of five months under a simple cycling protocol between 20 % and 100 % SOC. The cell-to-cell standard deviations obtained with the novel algorithm were 1.25 SOC-% and 1.07 SOH-% at beginning of cycling. A cell-averaged capacity loss of 9.9 % after five months cycling was observed. While the accuracy of single-cell SOC estimation was limited (probably owed to the flat voltage characteristics of the lithium iron phosphate, LFP, chemistry investigated here), single-cell SOH estimation showed a high accuracy (2.09 SOH-% mean absolute error compared to laboratory reference tests). Because the algorithm does not require observers, filters, or neural networks, it is computationally very efficient (three seconds analysis time for the complete data set consisting of eight cells with approx. 780.000 measurement points per cell).

Enhancing music recognition using deep learning-powered source separation technology for cochlear implant users.

Cochlear implant (CI) is currently the vital technological device for assisting deaf patients in hearing sounds and greatly enhances their sound listening appreciation. Unfortunately, it performs poorly for music listening because of the insufficient number of electrodes and inaccurate identification of music features. Therefore, this study applied source separation technology with a self-adjustment function to enhance the music listening benefits for CI users. In the objective analysis method, this study showed that the results of the source-to-distortion, source-to-interference, and source-to-artifact ratios were 4.88, 5.92, and 15.28 dB, respectively, and significantly better than the Demucs baseline model. For the subjective analysis method, it scored higher than the traditional baseline method VIR6 (vocal to instrument ratio, 6 dB) by approximately 28.1 and 26.4 (out of 100) in the multi-stimulus test with hidden reference and anchor test, respectively. The experimental results showed that the proposed method can benefit CI users in identifying music in a live concert, and the personal self-fitting signal separation method had better results than any other default baselines (vocal to instrument ratio of 6 dB or vocal to instrument ratio of 0 dB) did. This finding suggests that the proposed system is a potential method for enhancing the music listening benefits for CI users.

Abstract IA007: The WID-qEC test for simple and accurate endometrial cancer detection

Abstract Endometrial cancer incidence has been rising over the past ten years. Delays in diagnosis reduce survival and necessitate more aggressive treatment. We developed the WID-qEC test, a PCR-based test that evaluates DNA methylation in gene regions of GYPC and ZSCAN12, using 726 cervico-vaginal samples from women with and without endometrial cancer. So far, the WID-qEC test has been validated in an additional 1388 women in various settings, including a case/control study utilizing self-samples and a nested case/control set from a screening cohort including samples taken up to 3 years prior to endometrial cancer diagnosis. In a recent prospective observational study (the EPI-SURE study), the primary aim was to compare the performance of conventional index imaging tests (i.e., sonography) with the WID-qEC test for endometrial cancer detection. We invited all women aged ≥ 45 years with abnormal uterine bleeding attending a tertiary gynecological diagnostic referral center in the UK between June and November 2022 to participate. A cervicovaginal sample for the WID-qEC test was obtained prior to the current diagnostic pathway, and the test was performed blinded to the clinical outcome. Patients were followed until diagnostic resolution or until June 12, 2023. Four hundred of the eligible 474 women consented to study participation; one patient withdrew. Based on 603 index imaging tests (i.e., sonography), 186 (46.6%) women were recommended for a reference histology test (i.e., biopsy+/-hysteroscopy). Twelve cancers were diagnosed. 198 reference histology test procedures detected nine cancers and missed two; one further cancer was directly diagnosed at hysterectomy without a prior reference test. Endometrial thickness assessment from an ultrasound scan was possible in 379 (95.0%) of the 399 women and a pre-specified cut-off of ≥ 4.5mm had sensitivity, specificity, positive (PPV) and negative (NPV) predictive values of 90.9% (95% CI: 62.3-98.4), 79.1% (95% CI: 74.5-82.9), 11.8% (95% CI: 6.5-20.3) and 99.6% (95% CI: 98.0-99.9), respectively. Using a cut-off of &amp;gt; 3mm, the specificity was 45.8% (95% CI: 40.7–51.0) without a change in sensitivity. The WID-qEC test was possible in 390 (97.7%) of the 399 patients with 90.9% sensitivity (95% CI: 62.3-98.4), 92.1% specificity (95% CI: 88.9-94.4), a PPV of 25.6% (95% CI:14.6-41.1) and a NPV of 99.7% (95% CI: 98.3-99.9) when the pre-specified threshold (WID-qEC sumPMR ≥ 0.03) was applied. When a higher threshold was applied (WID-qEC sumPMR ≥ 0.3) the specificity increased to 97.3% (95% CI: 95.1-98.5) without a change in sensitivity. The WID-qEC test delivers fast results and shows improved performance compared with a combination of imaging index tests. Triage of women with abnormal uterine bleeding using the WID-qEC test could reduce the number of women requiring histological assessments for identification of potential malignancy and, specifically, reduce the false positive rate by up to 95% (from 52.6% based on the endometrial thickness of &amp;gt; 3mm to 2.6% based on a WID-qEC sumPMR ≥ 0.3). Citation Format: Martin Widschwendter, Iona Evans, Daniel Reisel, Allison Jones, Alba Bajrami, Simrit Nijjar, Sarah A Solangon, Rupali Arora, Elisa Redl, Lena Schreiberhuber, Isma Ishaq-Parveen, Julia Rothärmel, Chiara Herzog, Davor Jurkovic. The WID-qEC test for simple and accurate endometrial cancer detection [abstract]. In: Proceedings of the AACR Special Conference on Endometrial Cancer: Transforming Care through Science; 2023 Nov 16-18; Boston, Massachusetts. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(5_Suppl):Abstract nr IA007.

Independent clinic-based evaluation of dual POCTs for screening for HIV and syphilis in men who have sex with men in Italy, Malta, Peru, and the United Kingdom

IntroductionGlobally, the incidence of HIV and syphilis can be reduced by the use of validated point of care tests (POCTs). As part of the WHO PRoSPeRo Network, we aimed to evaluate the performance, acceptability, and operational characteristics of two dual HIV/syphilis POCTs (Bioline HIV/Syphilis Duo (Abbott) and DPP® HIV-Syphilis assay (Chembio) for the screening of HIV and syphilis amongst men who have sex with men (MSM).Method and analysesA cross sectional study of 2,577 MSM in Italy, Malta, Peru, and the United Kingdom (UK) presenting to seven clinic sites, were enrolled. Finger prick blood was collected to perform POCTs and results compared with standard laboratory investigations on venepuncture blood. Acceptability and operational characteristics were assessed using questionnaires. Diagnostic meta-analysis was used to combine data from the evaluation sites.ResultsBased on laboratory tests, 23.46% (n = 598/2549) of participants were confirmed HIV positive, and 35.88% of participants (n = 901/2511) were positive on treponemal reference testing. Of all participants showing evidence of antibodies to Treponema pallidum, 50.56% (n = 455/900) were Rapid Plasma Reagin (RPR) test reactive. Of HIV positive individuals, 60.62% (n = 354/584) had evidence of antibodies to T. pallidum, and of these 60.45% (n = 214/354) exhibited reactive RPR tests indicating probable (co)infection. For Bioline POCT, pooled sensitivities and specificities for HIV were 98.95% and 99.89% respectively, and for syphilis were 73.79% and 99.57%. For Chembio pooled sensitivities and specificities for HIV were 98.66% and 99.55%, and for syphilis were 78.60% and 99.48%. Both tests can detect greater than 90% of probable active syphilis cases, as defined by reactive RPR and treponemal test results. These dual POCTs were preferred by 74.77% (n = 1,926) of participants, due to their convenience, and the operational characteristics made them acceptable to health care providers (HCPs).ConclusionsBoth the Bioline and the Chembio dual POCT for syphilis and HIV had acceptable performance, acceptability and operational characteristics amongst MSM in the PRoSPeRo network. These dual POCTs could serve as a strategic, more cost effective, patient and healthcare provider (HCP) friendly alternative to conventional testing; in clinical and other field settings, especially those in resource-limited settings.

Pharmacokinetics and bioequivalence evaluation of two oral formulations of cotrimoxazole tablets in healthy Chinese volunteers under fasting conditions

This bioequivalence study was conducted to evaluate two oral formulations of cotrimoxazole tablets in healthy Chinese subjects. All 26 subjects recruited to this study were randomly and evenly classified into two groups and received a single dose (sulfamethoxazole: 400 mg and trimethoprim: 80 mg) of test cotrimoxazole tablets (generic drug) or reference cotrimoxazole tablets (branded drug). After a 7-day washout period, these subjects received one dose of reference drug or test drug. Blood samples were collected from participants before and up to 48 h after dosing to assess the concentration of sulfamethoxazole (SMX) and trimethoprim (TMP) in plasma and a plasma concentration-time curve was drawn. Then, the pharmacokinetics parameters were calculated accordingly. Our data revealed that there were no significant differences observed in the maximum plasma concentration (Cmax), area under the curve from time 0 to the last measurable concentration (AUC0-t), and area under the curve from time 0 to infinity (AUC0-∞) between the two formulations. For SMX, the 90% confidence intervals (CI) of the geometric mean ratio for Cmax, AUC0-t, and AUC0-∞ were 104.03-113.92%, 100.46-103.70%, and 100.41-103.81%, respectively. Similarly, for Trimethoprim (TMP), the 90% CI ranged from 98.54 to 106.95% for Cmax, from 99.31 to 107.68% for AUC0-t, and from 99.49 to 107.55% for AUC0-∞. Importantly, all these 90% CI values fell within the range of 80.00–125.00%, indicating that the test drug is bioequivalent to the reference drug. Furthermore, throughout the entire trial, no suspected serious adverse events were reported, indicating the safety profile of the newly developed generic cotrimoxazole. In summary, our study demonstrates that the newly developed generic formulation of cotrimoxazole is bioequivalent to the branded formulation under fasting conditions.

Application of a Biomimetic Nanoparticle-Based Mock Virus to Determine SARS-CoV-2 Neutralizing Antibody Levels in Blood Samples Using a Lateral Flow Assay.

The presence of neutralizing antibodies against SARS-CoV-2 in blood, acquired through previous infection or vaccination, is known to prevent the (re)occurrence of outbreaks unless the virus mutates. Therefore, the measurement of neutralizing antibodies constitutes an indispensable tool in assessing an individual's and a population's immunity against SARS-CoV-2. For this reason, we have developed an innovative lateral flow assay (LFA) capable of detecting blood-derived neutralizing antibodies using a biomimetic SARS-CoV-2 mock virus system. Here, functionalized gold nanoparticles (AuNPs) featuring the trimeric spike (S) protein at its surface imitate the virus's structure and are applied to monitor the presence and efficacy of neutralizing antibodies in blood samples. The detection principle relies on the interaction between mock virus and the immobilized angiotensin-converting enzyme 2 (ACE2) receptor, which is inhibited when neutralizing antibodies are present. To further enhance the sensitivity of our competitive assay and identify low titers of neutralizing antibodies, an additional mixing pad is embedded into the device to increase the interaction time between mock virus and neutralizing antibodies. The developed LFA is benchmarked against the WHO International Standard (21/338) and demonstrated reliable quantification of neutralizing antibodies that inhibit ACE2 binding events down to a detection limit of an antibody titer of 59 IU/mL. Additional validation using whole blood and plasma samples showed reproducible results and good comparability to a laboratory-based reference test, thus highlighting its applicability for point-of-care testing.

Test Setup for Investigating the Impact Behavior of Biaxially Prestressed Composite Laminates

Instrumented impact testing and compression-after-impact testing are important to adequately qualify material behavior and safely design composite structures. However, the stresses to which fiber-reinforced plastic components are typically subjected in practice are not considered in the impact test methods recommended in guidelines or standards. In this paper, a test setup for investigating the impact behavior of composite specimens under plane uniaxial and biaxial preloading is presented. For this purpose, a special test setup consisting of a biaxial testing machine and a specially designed drop-weight tower was developed. The design decisions were derived from existing guidelines and standards with the aim of inducing barely visible impact damage in laminated carbon fiber-reinforced plastic specimens. Several measurement systems have been integrated into the setup to allow comprehensive observation of the impact event and specimen behavior. A feasibility test was performed with biaxially prestressed carbon fiber-reinforced plastic specimens in comparison with unstressed reference tests. The compressive-tensile prestressing resulted in lower maximum contact forces, higher maximum deflections, higher residual deflections and a different damage pattern, which was investigated by light microscopic analysis. Finally, the functionality of the experimental setup is discussed, and the results seem to indicate that the test setup and parameters were properly chosen to investigate the effect of prestresses on the impacts behavior of composite structures, in particular for barely visible subsequent damages.

Examination of Diagnostic Performance of New IgG4 Rapid Test Compared with IgG- and IgG4-ELISAs to Investigate Epidemiology of Strongyloidiasis in Northeast Thailand.

Strongyloidiasis, caused by Strongyloides stercoralis, is a neglected tropical disease with a global distribution. The infection can be fatal in immunocompromised individuals, and accurate diagnosis leading to timely treatment can save lives. Serodiagnosis is a sensitive method for diagnosis and is recommended for screening high-risk individuals. A point-of-care rapid test will facilitate the screening activities, especially in low-resource settings. This study aims to apply a new IgG4 immunochromatographic test using S. stercoralis recombinant antigen (SsRapid® cassette test) and to compare it with in-house IgG and IgG4 enzyme-linked immunosorbent assays (IgG- and IgG4-ELISAs) using native Strongyloides ratti antigen to investigate the epidemiology of strongyloidiasis in northeast Thailand. A total of 300 people participated, with 136 males and 164 females of a similar mean age. The reference tests were fecal examinations using the formalin-ethyl acetate concentration technique and an agar plate culture technique. The prevalence of S. stercoralis determined by SsRapid (81.7%) was significantly higher than that by fecal examinations (43.3%) or by antibody detection by IgG-ELISA (53.0%) or IgG4-ELISA (44.0%). The diagnostic sensitivities of SsRapid, IgG-ELISA, and IgG4-ELISA were found to be 93.9%, 77.7%, and 63.1%, respectively. The rate of positive tests by the SsRapid was significantly correlated to the levels of Strongyloides-specific IgG4 and IgG antibodies. By all diagnostic methods, male participants had a significantly higher prevalence of strongyloidiasis than females. Age was significantly associated with the concentration of specific serum IgG but not with the SsRapid grading score. In conclusion, SsRapid was shown to be a sensitive and valuable diagnostic test for the epidemiology study of strongyloidiasis.

Evaluation of Phenotypic Tests for Carbapenemase Detection in Enterobacteriaceae in Tunisia.

Introduction: Resistance to carbapenems in Enterobacteriaceae is a challenge for public health. Carbapenemase production is the leading mechanism. This work aims to evaluate four phenotypic methods for carbapenemase detection in comparison with a molecular method. Materials and Methods: Thirty-seven nonrepeating Enterobacteriaceae strains with decreased susceptibility to ertapenem were included. Imipenem MIC, Modified Hodge Test (MHT), Neo-Rapid Carb Kit® and KPC, MBL, and OXA-48 Confirm Kit® were performed. Isolates were tested for blaOXA-48, blaNDM, and blaVIM genes by end-point polymerase chain reaction. The results of the molecular study were used as a reference test to determine the performances of the phenotypic tests. Results: Imipenem resistance does not seem to be a good marker for carbapenemase production with a sensitivity of 54% (95% CI: 38-71). MHT showed 82% sensitivity (95% CI: 65-91). Overall, the enzymatic test showed the best performances for carbapenemase detection with 100% sensitivity (95% CI: 89-100) and the best turnaround time. The characterization of carbapenemases classes by the combined discs test demonstrated 88% overall sensitivity (95% CI: 72-95). Conclusion: The results of this study support the combination of the enzymatic and the combined disc tests for carbapenemase detection in Enterobacteria.

Diagnostic accuracy of ultrasound versus X-ray for distal forearm fractures in children and adolescents: a systematic review and meta-analysis.

Utilizing ultrasound for the detection of distal forearm fractures in children presents a potential safe and radiation-free alternative compared to X-ray. A systematic review was undertaken to compare the diagnostic accuracy of ultrasound in detecting distal forearm fractures in children with X-ray imaging within the period spanning January 2010 to August 2023. The electronic databases MEDLINE and Cochrane CENTRAL were utilized for data retrieval. The QUADAS-2 tool was employed to assess the quality of the included studies. Subsequent statistical analysis was performed to calculate pooled sensitivity and specificity, positive and negative likelihood ratios, as well as the diagnostic odds ratio. Our meta-analysis included seventeen studies, encompassing a total of 2003 patients, 2546 ultrasound scans, and 1203 fracture cases as identified by the reference test (X-ray). The pooled sensitivity and specificity were 0.96 (95% CI: 0.93-0.98) and 0.96 (95% CI: 0.89-0.98), respectively. The positive likelihood ratio was 13.40 (95% CI: 7.97-21.50), the negative likelihood ratio was 0.06 (95% CI: 0.04-0.1), and the pooled diagnostic odds ratio was 209 (95% CI: 92.20-412.00). Our statistical analysis revealed low heterogeneity within our studied cohort. Our study indicates that ultrasound exhibits exceptionally high accuracy in the detection of distal forearm fractures in children and adolescents. It can be employed safely to either confirm or rule out a fracture, thus circumventing the need for potentially harmful radiation exposure in this vulnerable population. Future research endeavors should focus on establishing a universally accepted protocol for training and scanning methods to standardize practices and eliminate disparities in diagnostic procedures.

Self-Efficacy for Therapeutic Use of Self Questionnaire: Turkish Adaptation

Self-efficacy is pivotal for therapeutic relationships in occupational therapy. This study aimed to adapt SETUS to Turkish and assess the psychometric properties of SETUS-TR scale for Turkish occupational therapists. Beaton’s cross-cultural adaptation guidelines were followed adapting scale to Turkish. SETUS-TR showed strong internal consistency (Cronbach’s alpha: 0.83-0.94), acceptable construct validity, and reliable test-retest results (ICC: 0.87-0.94). Significant correlations (0.12-0.39) existed between SETUS-TR and reference test subscales. SETUS-TR is valid and reliable tool, evaluating Turkish occupational therapists’ self-efficacy in therapeutic use of self. This research furthers understanding of therapeutic use of self in occupational therapy.

Strain measurement with adaptive local feature extraction method based on special fiber OFDR system.

The optical fiber distributed strain sensor based on the optical frequency domain reflectometer (OFDR) preserves its dominant position in short-distance measurement fields with high spatial resolution, such as biomedical treatment, soft robot, etc. However, owing to the weak intensity of the Rayleigh backscattered signal (RBS) in the single-mode fiber (SMF) and complex computation, the large strain changes cannot be precisely and rapidly demodulated by the traditional cross-correlation method. In this work, the OFDR with backscattering enhanced optical fiber (BEOF) is proposed and demonstrated for fast and large strain measurement. By enhancing the RBS amplitude, the signal-to-noise ratio (SNR) is improved, resulting in a higher similarity between the reference signal and test signal, which is beneficial for the expansion of the strain measurement range. Moreover, the adaptive local feature extraction and matching (ALFEM) algorithm is presented and demonstrated, which replaces the traditional cross-correlation method for strain demodulation and fast measurement. On account of the enhancement ratio of BEOF, the dominant characteristic data segment can be extracted from whole wavelength data. In the experiments, the enhancing ratio of BEOF is designed as 10, resulting in the spatial resolution reaches 400µm and the strain measurement range is greatly increased to 4800µɛ. Further, the effectiveness of the ALFEM algorithm has been verified, in which the strain demodulation time is approximately 25% of that of the traditional method. This scheme fully exploits the enhancement characteristic of the BEOF and is also applicable to the systems based on other types of BEOF, different strain changes and sensing distances.