Reference Standard Research Articles

Sputum culture contamination and associated characteristics in a diagnostic clinical trial, Papua New Guinea.

Papua New Guinea is a high-burden multidrug-resistant TB (MDR/RR-TB) country that reports low rates of bacteriological confirmation. Sputum drug susceptibility testing for second-line drugs is important. Access to culture is limited. To evaluate the prevalence of mycobacterial sputum sample culture contamination and determine factors associated with contamination. A retrospective analysis of data from a TB diagnostic accuracy study that used culture as the diagnostic reference standard. Data included characteristics of people with presumptive pulmonary TB who provided sputum, sputum quality and culture results. Sputum (1-3 samples) was collected from 174 adults. The median age was 33 years (IQR 24-47). Of 337 samples sent for culture, 28% were contaminated. Contamination was strongly associated with samples self-collected by participants outside clinic hours (aOR 5.69; 95% CI 2.62-12.38). Contamination risk increased with delays in shipping to the reference laboratory (aOR 1.19 per day, 95% CI 1.10-1.29) beyond the minimum 3 days. Contamination was less frequent among people aged 35-44 years compared to 18-24 years (aOR 0.27, 95% CI 0.10-0.73). Sputum quality was not associated with culture contamination. Culture contamination could be reduced using spot sputum collection, expedited submission to laboratories and faster shipping when required.

Preparation of waste toner-derived magnetic adsorbent for analysis of lead in aqueous and oil-based foods

Waste toner powder contains carbon and ferrosoferric oxide, meaning it has potential as a magnetic adsorbent. Previous efforts have tried to improve its hydrophilicity for aqueous samples, but not non-aqueous food matrices such as edible oils. In this work, we proposed a one-step hydrothermal carbonization method using 50 % (v/v) acetic acid to prepare carboxyl-functionalised magnetic adsorbent for aqueous and oil-based food samples. Owing to the complexation of carboxyl groups and electrostatic attraction, the adsorption capacity for Pb(II) was 50.3 ± 0.4 mg g−1. Combined with GFAAS, the developed method demonstrated a high enhancement factor (91.0), a low detection limit (0.013 μg L−1) and was also validated by the certified standard reference material, including environmental water, rice flour and tea. Furthermore, successful applications were demonstrated in tap and lake water, orange juice, edible oil and mushrooms with recoveries ranging from 84.4 to 108 %.

Optimization and greenness assessments of the supramolecular solvent-assisted cloud point extraction method for copper spectrophotometric determination in water and food samples

For the first time, the green supramolecular solvents (SUPRASs)-based cloud point extraction (CPE) approach was created for copper spectrophotometric determination in food and water samples. SUPRASs were synthesized in six different forms and used as synergistic reagents. SUPRAS (water, salicylic acid, and THF) mixed with TritonX-114 (TX-114) to be the most efficient extraction solvent. The validation investigation found that the linearity range, limit of detection (LOD), limit of quantification (LOQ), enhancement factor (EF), and preconcentration factor (PF) are 0.2-700.0 μg L-1, 0.1 μg L-1, 0.33 μg L-1, 85.0, and 50.0, respectively. The technique's accuracy was calculated using standard reference materials (SRMs) (GBW07605 Tea Leaves and GBW10019 Apple) and ranged between 96.0 and 98.9%. Lastly, a novel SUPRAS-CPE approach was utilized to determine copper concentrations in real water, food tests, and SRMs. Furthermore, the SUPRAS-CPE conforms to green chemistry principles by using less both time and energy than previous studies. Also, the greenness values were determined by three recent tools. The Analytical Greenness Metric for Sample Preparation (AGREEprep), Complex Modified GAPI (ComplexMoGAPI), and Sample Preparation Metric of Sustainability (SPMS) programs produced results of 0.79, 86.0, and 8.42, respectively. These results are strongly aligned with both green ideals and environmentally friendly practices. The finding increases the possibilities for using SUPRAS-CPE to extract additional mineral ions.

PERSISTENT COAGULATION ABNORMALITIES IN RECOVERED COVID-19 PATIENTS FOLLOWING VACCINATION: A RETROSPECTIVE ANALYSIS

This retrospective observational study assessed persistent coagulation abnormalities in individuals who recovered from COVID-19 and subsequently received two doses of COVID-19 vaccination. The study enrolled 250 individuals, aged 20–50 years, and evaluated four primary coagulation markers: prothrombin time, activated partial thromboplastin time, D-dimer, and fibrinogen. Blood samples were analyzed using the STA-R coagulation analyzer. Results indicated that 10% of participants exhibited elevated D-dimer levels, 34% had elevated prothrombin times, and 85% displayed prolonged activated partial thromboplastin times, while 7.2% showed increased fibrinogen levels. Statistical analysis revealed significant deviations in D-dimer, activated partial thromboplastin time, and fibrinogen from standard reference ranges. These abnormalities suggest a possible hypercoagulable state post-vaccination, potentially due to vaccine-induced mechanisms that activate coagulation pathways. Findings align with reports of vaccine-induced thrombotic complications, especially in adenovirus-vectored vaccines. This study underscores the importance of monitoring coagulation parameters in vaccinated individuals with prior COVID-19 infection to ensure vaccine safety and efficacy. Future studies should investigate the underlying mechanisms of these coagulation changes and their clinical implications.

Comparison of the STANDARD M10 C. difficile, Xpert C. difficile, and BD MAX Cdiff assays as confirmatory tests in a two-step algorithm for diagnosing Clostridioides difficile infection.

Current guidelines recommend a two-step algorithm rather than relying solely on a single test for diagnosing Clostridioides difficile infection. This algorithm starts with enzyme immunoassay (EIA) for detecting glutamate dehydrogenase (GDH) and toxins A/B, followed by nucleic acid amplification test (NAAT) for GDH-positive but toxin-negative cases. This study compared the performance of three commercial NAATs: the STANDARD M10 C. difficile, Xpert C. difficile, and BD MAX Cdiff assays, utilized as confirmatory testing of the two-step algorithm. Two hundred archived stool specimens, previously tested GDH-positive but toxin-negative by EIA, were analyzed in parallel with these NAATs and toxigenic culture, which served as the reference standard. Sensitivity, specificity, positive predictive value, and negative predictive value were 89.1%, 92.6%, 94.6%, and 85.2%, respectively, for the M10 assay; 95.8%, 86.4%, 91.2%, and 93.3%, respectively, for the Xpert assay; and 89.8%, 91.4%, 93.8%, and 86.0%, respectively, for the BD MAX assay. The rates of invalid results were 1.0%, 0.5%, and 1.0% for the M10, Xpert, and BD MAX assays, respectively. In conclusion, the M10 assay is a reliable diagnostic tool, performing comparably to the Xpert and BD MAX assays when used as confirmatory testing in the two-step algorithm.IMPORTANCEWhile numerous studies have assessed nucleic acid amplification tests (NAATs) as stand-alone tests for diagnosing Clostridioides difficile infection, limited research has compared their performance as confirmatory tests in a two-step algorithm. This study evaluated the performance of three commercial NAATs (M10, Xpert, and BD MAX assays) using 200 archived stool specimens initially tested as glutamate dehydrogenase (GDH)-positive but toxin-negative by GDH/toxin A/B enzyme immunoassay, the first step in the two-step algorithm. All three assays demonstrated high sensitivity (89.1% to 95.8%) and specificity (86.4% to 92.6%), with low rates of invalid results (≤1%). Our findings suggest that the M10 assay performs comparably to the Xpert and BD MAX assays when used as confirmatory testing in the two-step algorithm. Offering similar performance and turnaround time to these widely used assays at a slightly lower cost, the M10 assay serves as a practical alternative in this setting.

Microscopic Characterization of Achillea santolina L. Flower Through Light Microscopy and Scanning Electron Microscopy.

This study is a comprehensive account of microscopic assessment of flower of Achillea santolina L., a medicinally important species of the genus Achillea from Pakistan. The study was aimed to provide data for the quality control and standardization of A. santolina L. flower. The microscopic characterization has been carried out through light microscopy and scanning electron microscopy. Various characteristic histological features of phyllaries, ray floret, disc floret, anther wall, filament, stigma, style, and ovary were observed. The pollens were found as tricolporate, spheroidal while the surface ornamentation was echinate. Qualitative and quantitative palyno-anatomical assessment was carried out through scanning electron microscopy. The exine thickness and the width of spines were calculated. The P/E ratio characterized the shape of pollen as oblate-spheroidal and sub-oblate in polar and equatorial views respectively. The elemental analysis of the flower through SEM-EDX showed the presence of various elements. Phytochemical screening of flower showed the presence of carbohydrates, flavonoids, fixed oils, glycosides, phenols, steroids, tannins, terpenoids, and coumarins. UV-vis spectra of the ethanol extract showed characteristics peaks in both ultraviolet and visible regions. This work will provide a standard reference for the correct identification of A. santolina L. an important aspect in the quality control. Additionally, the data produced by phytochemical, elemental and florescence analysis, and UV-visible spectroscopy will help in developing standards for this herb that will be useful for research and development and manufacturing of herbal products.

Improved MR Detection of Optic Nerve Demyelination With MP2RAGE-FLAWS Compared With T2-Weighted Fat-Saturated Sequences.

Nonenhanced T1-w sequences such as magnetization-prepared 2 rapid acquisition gradient echo (MP2RAGE) and derived fluid and white matter suppression (FLAWS) have demonstrated high performance for detecting brain parenchymal and cervical spine demyelinating lesions in multiple sclerosis. However, their potential for identifying optic nerve (ON) demyelination remains unexplored. The aim of this study was to evaluate the performance of compressed sensing-accelerated (CS) MP2RAGE-FLAWS imaging for detection of ON demyelination lesions compared with T2-w fat-saturated (FS) TSE imaging in a clinical setting. We conducted a retrospective study of magnetic resonance scans acquired on patients with central nervous system demyelinating disorders between January and December 2022. Inclusion criteria were the acquisition in the same session of a brain CS-MP2RAGE-FLAWS imaging and a combination of axial + coronal T2-w FS orbital sequences. A 4-step radiological analysis-including blinded and consensus readings-assessed ON lesion detection. The reference standard was the final reading session of radiologists using the entire patient file. Sensitivities and specificities of both sequences were computed and compared using McNemar χ2 tests. Thirty-nine patients (mean age: 43 ± 14 years; 25 women) were analyzed, including 34 with multiple sclerosis, 2 with MOGAD (myelin oligodendrocyte glycoprotein antibody-associated disease), 1 with NMOSD (neuromyelitis optica spectrum disorder), and 2 with indeterminate demyelinating disease. Among the 78 ONs analyzed, 64 lesions were detected with CS-MP2RAGE-FLAWS as opposed to 37 with 2D T2-w FS imaging, corresponding to a total of 41 and 27 affected nerves, respectively. CS-MP2RAGE-FLAWS exhibited higher sensitivity for overall detection of ON lesions compared with 2D T2-w FS imaging (97.5% vs 67.5%, P = 0.001) without reducing the specificity. Improved lesion detectability with CS-MP2RAGE-FLAWS was significant compared with 2D T2-w FS in intraorbital and intracanalicular segments (respectively, 92.3% vs 50% and 96.3% vs 66.7%; P < 0.05). There was no difference in sensitivity (P = 0.69) or specificity (P = 0.99) regarding the intracranial segment analysis. CS-MP2RAGE-FLAWS sequence improves ON lesion detection compared with conventional 2D T2-w FS, especially in the intraorbital segment, while simultaneously providing whole-brain and cervical spinal cord imaging at no additional time cost.

Rethinking the missions and functions of public research institutes: evidence from Iranian PRIs

Abstract Public research institutes (PRIs) are pivotal in national and sectoral innovation systems and the transition to a knowledge-based economy. So, the current study has reassessed these institutes’ functions and suggested policy recommendations to augment their influence in moving toward a knowledge-based economy. The findings of this research reveal that functions such as innovation hub and specialized accelerator; strategic and problem-oriented research management platform; standard and regulatory reference; specialized technical service center; center for cooperation, transfer, and dissemination of technology; and the hub of technology and policy intelligence in a specific industrial sector are crucial functions of PRIs in transitioning to a knowledge-based economy. Additionally, to foster a conducive environment for the influence of PRIs in actualizing a knowledge-based economy, policies related to governance and division of responsibilities, stimulation of both supply and demand sides, strengthening the linkage between the supply and demand sides, and provisioning supportive environment and infrastructure are recommended.

The diagnostic validity of the cervical side bend-rotation test for C 1/2 dysfunction

ABSTRACT Introduction Neck pain and headaches are common, with a reported lifetime prevalence of up to 66%. Upper cervical segmental dysfunction has been implicated as meaningful in neck pain and multiple headache types. Several tests have been described to assess upper cervical joint dysfunction, including the flexion-rotation test (FRT), the side bend-rotation test (SBRT), and joint play assessment (PA). The purpose of this study was to determine the diagnostic validity of the SBRT to detect C1–2 dysfunction in a sample of people with medically diagnosed sinus headaches and controls. Methods Design: prospective diagnostic accuracy study, occurring during an observational case-control study in a sample of individuals with medically diagnosed sinus headaches. All participants were assessed using the SBRT, FRT, and C1–2 joint play assessments. The diagnostic accuracy of the SBRT was assessed using a reference standard of concurrent positive FRT (a loss of at least 10° from expected ROM (≤34°)) and restriction of C1–2 joint play. Cut-off scores for the SBRT were determined using ROC curve analysis, and tests of diagnostic accuracy were calculated using 2 × 2contingency tables. Results A total of 80 individuals (40 headache, 64 female, mean age 32.9 ± 13.8 yrs.) were included in the study. Mean ROM for the tests was: SBRT 31.4 ± 9.4°, FRT 44.9 ± 9.5°, and C1–2 mobility 22 hypomobile/58 normal. An SBRT cutoff score of <25° was confirmed using ROC curves. Using this cutoff score, the SBRT demonstrated 100% sensitivity and 62% specificity to detect C1–2 hypomobility. Discussion/conclusion The SBRT, using a cutoff score of ≤25°, appears to be a sensitive test to detect C1–2 dysfunction. Based on the strong sensitivity and negative predictive values, scores greater than 25° may effectively rule-out C1–2 dysfunction. The SBRT should be considered as part of a sequential clinical decision-making process when screening for C1–2 dysfunction, although further research is required to improve generalizability of these findings.

Validation of American College of Radiology Bone Reporting and Data System (Bone-RADS) Version 2023 for diagnosis of malignant tumors of appendicular bone on conventional radiographs

PurposeTo evaluate the diagnostic performance of the American College of Radiology(ACR) Bone Reporting and Data System (Bone-RADS) in diagnosis of malignant tumors of the appendicular bone on conventional radiographs. MethodsPrimary and secondary tumors of appendicular bone in patients who underwent radiographic and MRI examinations were classified into benign, intermediate, and malignant using a reference standard of histopathology, imaging follow-up, or clinical-radiologic consensus. Two radiologists assessed five radiographic features (margin, periosteal reaction, endosteal erosion, pathologic fracture, and extra-osseous mass), scored point total (points from radiographic features and a history of cancer), and assigned Bone-RADS categories. The diagnostic performance of Bone-RADS and interreader agreements were calculated. ResultsA total of 778 patients (507 benign, 45 intermediate, and 226 malignant tumors) were included. Bone-RADS showed high discrimination performance, with areas under the receiver-operating characteristics curve of 0.940–0.957 for point total and 0.895–0.900 for categorization. Bone-RADS had high sensitivity (95.2 %–99.1 %) and negative predictive value (NPV) (96.4 %–99.5 %), but relatively low specificity (65.0 %–68.6 %) and positive predictive value (PPV) (53.7 %–61.9 %). Interreader agreements were good to excellent for Bone-RADS point total (ICC = 0.850), categorization (k = 0.739), and most of the radiographic features (k = 0.621–0.822), except for endosteal erosion (k = 0.537) and extra-osseous mass (k = 0.234). ConclusionIn diagnosis of malignant bone tumors, ACR Bone-RADS showed high discrimination performance, with high sensitivity and NPV, but relatively low specificity and PPV. Nevertheless, relatively low interobserver agreement in some radiographic features and the consensus-based points system in Bone-RADS warrant further research and possible updates.

Development of a microhaplotype panel for steelhead/rainbow trout (Oncorhynchus mykiss) and application for phylogenetic analysis in California

AbstractAdvances in high-throughput sequencing and bioinformatic data processing have prompted a transition in wildlife and fisheries genetics from the use of allozymes, mtDNA, or microsatellites towards markers that are more amenable to genotyping by sequencing, increasing the amount of data obtained for a lower cost with less time-consuming techniques. Microhaplotypes are novel multi-allelic genetic markers that utilize a high-throughput genomic amplicon sequencing approach to genotype large numbers of individuals for parentage and kinship analysis and population genetic studies, including applications in monitoring and fisheries management. We describe the development of a panel of microhaplotypes for Oncorhynchus mykiss, a species of high cultural and economic importance throughout its native range and globally through introductions for aquaculture and due to its reputation as a prized sport fish among recreational fishers. The panel includes 124 loci presumed to be neutral, a marker for the sex determination locus (SdY), and 10 loci targeting previously identified adaptive genomic variants associated with important life-history traits in this species. We demonstrate that this panel provides high resolution for phylogeographic and other genetic analysis and on initial standardized reference population genetic baseline of California O. mykiss.

Pioneering NMR-based dereplication for identifying novel quinolone additives in personal care products: A new frontier in public health protection

Personal care products (PCPs) are often adulterated with antimicrobial agents, such as quinolones, which pose risks to consumer safety and challenge regulatory oversight. Current detection methods rely on standard reference substances and are limited in identifying novel quinolone isomers and structural derivatives. In this study, we present the first use of MixONat, an advanced dereplication tool, combined with 13C NMR spectroscopy to detect illegal quinolone additives in PCPs. Key advancements include the establishment of an in-house quinolone database, innovative sample pretreatment methods, and the integration of these elements to improve the detection of new illegal additives in PCPs. Standard addition experiments in both blank matrices and commercial cosmetics successfully identified new quinolones not included in the database, with effective differentiation of stereoisomers such as ofloxacin and levofloxacin. The proposed approach significantly improves detection efficiency and accuracy, bolstering PCP safety regulations and contributing to public health protection.

A Metabolomics Strategy Combining Countercurrent Separation and qNMR for the Comprehensive Chemical Evaluation of Polygoni Multiflori Radix Processing.

Polygoni Multiflori Radix (PMR) is commonly used in traditional medicine as both raw and processed forms. Raw PMR was prepared into processed PMR via processing procedure; however, there is a lack of standardized protocols ensuring the completeness of processing. This aims to develop a strategy based on a metabolomics approach for the comprehensive chemical profiling and comparison of raw and processed PMR and establish a basis for PMR processing standardization. Methanol extracts of raw and processed PMR were fractionated by centrifugal partition chromatography (CPC) with an optimized two-phase solvent system based on the partition coefficient calculated from the shake-flask method to produce primary (1°Ms)- and secondary metabolites (2°Ms)-enriched fractions. These fractions were profiled by 1D and 2D and selective 1D NMR experiments, spectral fitting, and comparison with reference standards. The profiled compounds were quantified via quantitative 1H NMR (qHNMR) to show the chemical changes, which were correlated with changes in antioxidant effects on H2452 cells. A CPC method was developed to efficiently separate 1°Ms- and 2°Ms-enriched fractions. This method achieved high purity of the major stilbene in PMR in a single run. qHNMR effectively quantified four 2°Ms and twenty-one 1°Ms in both raw and processed PMR, including meso-butane-2,3-diol, which was first reported from processed PMR. Changes in chemical composition of PMR because of processing are highly correlated to the increase of antioxidant activity. A convenient and cost-effective strategy for the comprehensive chemical profiling of raw and processed PMR was developed by combining countercurrent separation and qHNMR. This approach will contribute to the standardization of medicinal herbal materials.

Long-Term Risk of Clinically Significant Prostate Cancer in Biopsy-Negative Patients With Baseline Biparametric Prostate MRI.

The long-term prevalence of clinically significant prostate cancer (csPCa) in patients with initial negative prostate biopsy is unknown. To investigate the rate of csPCa of men with initial negative biopsy. Retrospective analysis of prospectively collected data. A total of 197 men (mean age 63 years [SD ±6.98, range 29-79]) without csPCa on initial biopsy and available baseline biparametric prostate MRI (bpMRI). 3.0 T, turbo spin-echo T2-weighted (axial and sagittal) and three sets of diffusion-weighted imaging using single-shot spin-echo planar imaging (5 b-values 0-500 seconds/mm2; 2 b-values 0 and 1500 seconds/mm2, and 2 b-values 0 and 2000 seconds/mm2). BpMRI was read using Prostate Imaging Reporting Data System (PI-RADS) v2.1. Systematic or targeted biopsy results served as reference standard. Continuous variables were compared using Kruskal-Wallis rank sum test. Categorical variables were compared using either Fisher's exact test or Pearson's chi-square test. Uni- and multivariate regression odds ratios (95% confidence interval) were used to study factors affecting csPCa being diagnosed during follow-up. Time to diagnosis of csPCa is calculated using the Kaplan-Meier method. Of 197 men, 74 (38%), 57 (29%), and 66 (34%) presented with PI-RADS 1-2, 3, and 4-5 findings in the baseline bpMRI. During the median follow-up of 52 months, 8.1%, 5.3%, and 18.2% of these men were diagnosed with csPCa, respectively. Baseline PI-RADS finding was the only factor that associated with csPCa found during the follow-up. Baseline bpMRI with PI-RADS scores 1-3 and initial biopsies negative of csPCa had low rate of csPCa during follow-up, which supports more conservative follow-up for them but further research with longer follow-up is warranted. 3 TECHNICAL EFFICACY: Stage 2.

Diagnostic Accuracy of Lung and Abdominal Ultrasound for Tuberculosis in a German Multicenter Cohort of Patients With Presumed Tuberculosis Disease.

There is limited evidence on point-of-care ultrasound for tuberculosis (TB), but studies suggest high sensitivity, especially for lung ultrasound (LUS). However, insufficient data are available on specificity of the examination and its generalizability to a broader patient population. Our study aimed to establish accuracy for lung, chest, and abdominal ultrasound, individually and in combination, for TB diagnosis. We conducted a prospective diagnostic accuracy study among consecutive adult out- and inpatients with probable TB in three German referral hospitals. We applied a comprehensive standardized ultrasound protocol. TB diagnosis was established by a microbiological reference standard including polymerase chain reaction and culture. A total of 102 participants originating from 30 different countries were enrolled. HIV prevalence was 7/99 (7%) and 73/102 (72%) had confirmed TB. TB was limited to the lungs in 15/34 (44%) of refugees and 27/39 (69%) in nonrefugees. Focused assessment with sonography for HIV-associated tuberculosis had a sensitivity of 40% (95% confidence interval [CI], 30-52) and specificity of 55% (95% CI, 38-72). Additional findings, such as small subpleural consolidations on LUS had a high sensitivity (88%; 95% CI, 78-93), but a low specificity (17%; 95% CI, 8-35). Larger consolidations in the lung apices had a sensitivity of 19% (95% CI, 12-30) and a specificity of 97% (95% CI, 83-100). Our study establishes the first data on LUS performance against a comprehensive reference standard. Overall, our data suggest that ultrasound does not meet the requirements for triage but previously described and novel ultrasound targets in combination could aid in the clinical decision making.Registry: DRKS00026636.

Large-Volume Injection and Assessment of Reference Standards for n-Alkane δD and δ13C Analysis via Gas Chromatography Isotope Ratio Mass Spectrometry.

Compound-specific stable isotope analysis of hydrogen (δD) and carbon (δ13C) in organic compounds is a valuable tool in biogeochemical research. A key limitation of this method is the relatively large amount of sample required to achieve desirable precision. We developed a large-volume (20 μL) injection method that allows for high throughput analysis of less concentrated samples and tested it for δ13C and δD measurements of n-alkanes. We also conducted a comparison of reference standards and assessed several methods to normalize and correct n-alkane δD and δ13C measurements. The mean precision of the δD method based on 233 environmental n-alkane samples (two to three replications per sample) is 4.0‰ (1σ, estimated from the weighted mean of the pooled unbiased standard deviations) and 0.46‰ (1σ) for δ13C from 37 environmental samples (two to three replications per sample). The evaluation of reference standards shows that the use of n-alkane standards with large offsets in δD values in adjacent n-alkane chains can lead to biases in measurement correction. The large-volume injection method shows good reproducibility of δ13C and δD measurements of n-alkanes and reduces the required sample concentration by about 80%. We propose that for δD measurements, a reference standard set should be used in which each reference standard has a limited range of δD values and no adjacent n-alkane chains, to minimize memory effects.

Rapid test for hepatitis B core-related antigen to identify people living with hepatitis B having high viral load in Cameroon

This study presents a retrospective assessment of the diagnostic performance of the newly developed hepatitis B core-related antigen rapid diagnostic test (HBcrAg-RDT) in detecting plasma samples with elevated hepatitis B virus (HBV) DNA levels (≥200,000 IU/ml) in Yaoundé, Cameroon. Samples were collected consecutively from treatment-naïve adults living with HBV between January 1, 2021, and June 30, 2023. Analyzing 146 samples from participants with a median age of 36 years, the HBcrAg-RDT exhibited a sensitivity of 97.5% (95% CI: 86.8–99.9) and a specificity of 77.4% (68.2–84.9) when compared to real-time PCR as the reference standard. These findings suggest that HBcrAg-RDT holds promise as a valuable point-of-care tool for diagnosing high HBV DNA levels, particularly in resource-limited settings. Further research will refine its practicality and effectiveness.

A comprehensive pharmacokinetic strategy for systematic evaluation of whole interaction of different constituents in Astragali Radix -Fructus Corni to improve diabetic kidney disease

Ethnopharmacological relevanceAstragali-Radix (the dried root of Astragalus mongholicus Bunge, AR) - Fructus Corni (the dried ripe fruit of Cornus officinalis Sieb. et Zucc., FC) has been used as a herb-pair remedy to treat diabetic kidney disease (DKD) for hundred years. Polysaccharides, saponins, and flavonoids in AR, and the iridoid glycosides in FC were deemed as the main bioactive constituents that can offer beneficial nephroprotective activities. A systematic evaluation of the nephroprotective effects of AR-FC herb pair, the main bioactive constituents extracted from the herb pair, and their combinations in different ratios was performed, CG6 (polysaccharides, flavonoids, saponins, and iridoid glycosides, in a ratio of 2:3:1:2) as the best compatibility proportion was screened out in our previous study. Aim of the studyThis study aimed to investigate the pharmacokinetic characteristics of AR-FC herb-pair in DKD rats, and explore the interactions between constituents from AR-FC and the rational compatibility of different constituents. Materials and methodsThe protective effect of AR-FC and CG6 on renal injury caused by DKD was first verified by histopathological examination. Then, an analytical method based on UHPLC-Q-TOF-MS and UHPLC-QqQ-MS/MS for qualitative and quantitative metabolites without reference standards was established and applied to pharmacokinetic (PK) studies in following different aspects: between single groups (polysaccharides, flavonoids, saponins and iridoid glycosides) and compatibility groups (AR-FC, CG6), in normal and DKD rats, in single-dose administration and long-term administration. ResultsPathological observations confirmed that AR-FC could improve renal injury in DKD rats. PK profiles of nine prototypes and four metabolites in various groups were obtained, revealing the compatibility of multiple constitutes, pathological states, and long-term administration could alter PK characteristics of the main components from AR-FC, and promoting the absorption of them (Cmax, AUC0-t, and AUC0-t increased). Notably, co-administration of iridoid glycosides could significantly increase the absorption of flavonoids and saponins in vivo. The pharmacokinetics based on homologous compounds revealed that saponins first acted, then its initial metabolites affected flavonoids, and ultimately the metabolites of flavonoids influenced iridoid glycosides. ConclusionThis study demonstrated the existence of interactions between constituents from AR-FC herb-pair and the importance of their rational compatibility. It provides experimental evidence for developing a therapeutic agent based on AR-FC (especially CG6) to treat DKD. It is also expected to provide a reference for the multi-component pharmacokinetic study of other herbal medicines.

Comparison of intravoxel incoherent motion and diffusion kurtosis imaging and 18- FDG PET/CT in response assessment in rectosigmoid carcinoma.

To evaluate the performance of intravoxel incoherent motion and diffusion kurtosis imaging (IVIM- DKI) in response assessment of rectosigmoid carcinoma to chemo-radiotherapy (CRT) and compare with 18-FDG PET/CT parameters. A total of 30 patients of recto-sigmoid cancer on CRT underwent baseline staging and follow-up with IVIM - DKI. Out of this cohort, 20 patients underwent 18-FDG PET/CT. IVIM- DKI MRI and PET/CT parameters were noted from both pre and post-chemoradiotherapy (done at 6 weeks after completion) scans. Quantitative IVIM-DKI parameters, viz. apparent (ADC) and molecular (D) diffusion coefficient, perfusion coefficient (f), and kurtosis (K) were measured from non-necrotic areas and semi-quantitative PET parameters including SUV max, SUV ratio, metabolic tumor volume (MTV), total lesion glycolysis (TLG) were also measured. All these parameters correlated with the patient's response keeping RECIST 1.1 criteria as reference standard. A statistically significant increase in D and ADC with a significant decline in K was noted after therapy in the entire cohort. These changes were observed in both responders as well as non-responders. No significant differences were observed in the percentage changes of these parameters post therapy amongst both groups. Among 20 patients with follow-up PET/CT imaging, a significant decline in all parameters of primary lesion was seen post-therapy. Responders (n = 12) showed a significant decline in MTV and TLG from baseline after therapy, whereas non-responders did not show any such decline. Change in TLG (ɗ TLG), followed by ɗ MTV had the strongest correlation with a positive response. A ɗ TLG value of ≥ 54.19 carried a 79% sensitivity and 83% specificity in differentiating responders from non responders. 18-FDG PET/CT is a more accurate single modality for assessing both response and tumor burden post therapy, while ADC and D from IVIM MRI are useful adjuncts to response assessment.

Prediction of vesicouterine adhesions by transvaginal sonographic sliding sign technique: validation study.

Adhesions between the uterus, bladder and anterior abdominal wall are associated with clinical sequelae, including chronic pelvic pain and dyspareunia, and can also yield complications during surgery. The transvaginal sonographic (TVS) sliding bladder sign is a minimally invasive diagnostic tool to evaluate the presence of vesicouterine adhesions. This study aimed to determine the predictive value and intra- and interobserver variation of the TVS sliding bladder sign in the assessment of vesicouterine adhesions. This was a prospective observational double-blind diagnostic accuracy study conducted at the Amsterdam University Medical Center. Patients scheduled for gynecological laparoscopic surgery for a benign disorder between January 2020 and December 2022 were included consecutively. All patients underwent preoperative TVS, including a dynamic sliding bladder sign examination in our outpatient clinic. Videoclips of the TVS scans were stored for offline assessment and used as an index test. The recordings of both TVS and laparoscopy were evaluated for diagnostic characteristics of vesicouterine adhesions by independent assessors, who were blinded to the clinical situation in addition to the laparoscopic findings when assessing recordings of TVS and vice versa. The presence of adhesions on laparoscopy was used as the reference standard. The positive predictive value (PPV), negative predictive value (NPV), specificity and sensitivity of the sliding bladder sign were calculated. In addition, inter- and intraobserver variability of the sliding bladder sign on TVS were assessed. Of 116 included women, 57 had a negative sliding bladder sign on TVS, while on laparoscopy, 51 women had mild and 28 had severe vesicouterine adhesions. A negative sliding bladder sign had a PPV of 94.7% (95% CI, 88.9-100%) for the presence of any vesicouterine adhesions, and a positive sliding bladder sign had a specificity of 91.9% (95% CI, 83.1-100%). For severe adhesions, the negative sliding bladder sign had a sensitivity of 89.3% (95% CI, 77.8-100%) and a positive sliding bladder sign had a NPV of 94.9% (95% CI, 89.3-100%). When using Cohen's kappa coefficient, inter- and intraobserver agreement between assessors was good. Sliding bladder sign evaluation using TVS is a reliable diagnostic tool for the prediction of vesicouterine adhesions on laparoscopy. A negative sliding bladder sign indicates the presence of vesicouterine adhesions, while a positive sliding bladder sign makes the presence of severe adhesions unlikely. Establishing vesicouterine adhesions by TVS may optimize preoperative planning, and can be used for future studies to evaluate the relationship between symptomatology and vesicouterine adhesions and, subsequently, the effect of adhesion-prevention interventions. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.