High Sensitivity Research Articles

Simultaneous bending and temperature measurement based on a superimposed fiber grating sensor

A compact and novel superimposed fiber grating (SI-FG) sensor for simultaneous measurement of temperature and bending based on UV-induced FBG cascaded with a multimode fiber (MMF) embedded ultra-long period fiber grating (MMF-EULPFG) has been proposed and experimentally validated. The MMF-EULPFG acts as a temperature and bending sensing unit and was fabricated by periodically splicing a non-UV-non-photosensitive MMF and a UV-photosensitive single-mode fiber (SMF) which is so called cleaving-splicing method. Due to the periodic refractive index modulation, the 6-period SMF-MMF structure based MMF-EULPFG with a total length of 2.7 mm forms transmission spectra with a −17 dB dip. The proposed SI-FG sensor exhibits high bending and temperature sensitivities of 17.096 nm/m−1 and −0.238 nm/℃, respectively. The UV-induced FBG is fabricated in the initial segment of UV-sensitive fibers within EULPFG by UV exposure method. The dip of FBG transmission spectra also shows response to bending and temperature. By utilizing a matrix obtained from the experimental results, simultaneous measurement of temperature and bending can be achieved. Due to its compact structure and high sensitivity, the proposed novel SI-FG sensor can be used as a competitive all-fiber sensor for structural health monitoring and 3D-shape sensing.Index Terms: Optical fiber sensor, long period fiber grating, superimposed fiber grating, simultaneous measure.

Experimental teaching reform of polymer molar mass determination using gel permeation chromatography coupled with light scattering

Gel permeation chromatography coupled with light scattering (GPC-LS) is among the most common methods for determining the molar masses of polymers. GPC-LS is widely used in polymer science research and has been adopted for many industrial applications owing to its high sensitivity, accuracy, and precision. The determination of polymer molar masses using GPC-LS is an important experimental component of the "Polymer Physics Experiments" course. However, the present GPC-LS experimental teaching content tends to be overly simplistic and lacking in depth. Herein, the original experimental content is expanded and multiple sets of experiments are redesigned: (1) Using commercial polystyrene as an experimental sample, the molar mass, molar mass distribution, radius of gyration, and other molecular structure parameters are determined using GPC-LS; (2) Using two polyacrylonitriles with similar molecular structure parameters, subtle differences in the molar mass distributions of the samples are explored using differential mass distribution curves; (3) By comparing the chromatograms of a series of polyethylene glycols with different molar masses, the effect of molar mass on chromatographic peaks is investigated; and (4) For three different polymers (polyacrylonitrile, poly(methyl methacrylate), and poly(β-cyclodextrin)), the polymer chain conformations are analyzed using conformation plots (i.e., radius of gyration vs. molar mass). In addition, the experimental teaching method is modified to convert passive learning into active learning, thereby improving the students' self-directed learning ability. This experimental teaching reform will help students obtain a more comprehensive understanding of GPC-LS principles and applications, stimulate their enthusiasm for learning, and improve the teaching quality of the experimental course.

Requirement of Repeated Serum VEGF Measurements in POEMS Syndrome.

POEMS syndrome is often associated with a poor prognosis. Elevated serum vascular endothelial growth factor (sVEGF) is a useful diagnostic marker with high sensitivity and specificity. However, the relationship between sVEGF elevation and polyneuropathy in POEMS syndrome remains controversial. We herein report a case of polyneuropathy without sVEGF elevation at the first admission. However, at 21 months after the onset, the patient tested positive for sVEGF and was diagnosed with POEMS syndrome. Therefore, it is important to repeatedly measure sVEGF levels in patients with polyneuropathy with an atypical course when POEMS syndrome is suspected, even if the initial sVEGF level is normal.

Carbon Nanocomposites-based Electrochemical Sensors and Biosensors for Biomedical Diagnostics.

Detection of emergent biomolecules or biomarkers remains crucial for early diagnosis in advancing healthcare monitoring and biomedicine. The possibility for rapid detection, real-time monitoring, high sensitivity, low detection limit, good selectivity, and low cost is central, among other significant issues for advancing point-of-care diagnosis. Carbon-based nanocomposites have been employed as sensing materials for various biomarkers due to their high surface-to-volume ratio, high electrical conductivity, chemical stability, and biocompatibility. The carbon nanomaterials, such as carbon nanotubes (CNTs), graphene (GR), carbon quantum dots (CQDs), carbon fibres (CFs), and their nanocomposites have broadly integrated with numerous sensing electrode materials for the detection of biomarkers under various experimental settings. The present review includes the recent advances in the development of carbon nanomaterials-based electrochemical sensors and biosensors for biomedical applications. The preparation, electrode preparation, effective utilization of carbon-derived nanomaterials, and their sensing performances towards numerous biomarkers have been highlighted. The state-of-the-merit, challenges, and prospects for designing carbon nanocomposites-based electrochemical sensor/biosensor platforms for biomedical diagnostics have also been described.

Graphene Terahertz Devices for Sensing and Communication.

Graphene-based terahertz (THz) devices have emerged as promising platforms for a variety of applications, leveraging graphene's unique optoelectronic properties. This review explores recent advancements in utilizing graphene in THz technology, focusing on two main aspects: THz molecular sensing and THz wave modulation. In molecular sensing, the environment-sensitive THz transmission and emission properties of graphene are utilized for enabling molecular adsorption detection and biomolecular sensing. This capability holds significant potential, from the detection of pesticides to DNA at high sensitivity and selectivity. In THz wave modulation, crucial for next-generation wireless communication systems, graphene demonstrates remarkable potential in absorption modulation when gated. Novel device structures, spectroscopic systems, and metasurface architectures have enabled enhanced absorption and wave modulation. Furthermore, techniques such as spatial phase modulation and polarization manipulation have been explored. From sensing to communication, graphene-based THz devices present a wide array of opportunities for future research and development. Finally, advancements in sensing techniques not only enhance biomolecular analysis but also contribute to optimizing graphene's properties for communication by enabling efficient modulation of electromagnetic waves. Conversely, developments in communication strategies inform and enhance sensing capabilities, establishing a mutually beneficialrelationship.

CXCR4-Targeted 68Ga-Pentixafor PET/CT Imaging in Inflammatory Bowel Disease.

To investigate the role of CXCR4-targeted 68Ga-pentixafor PET/CT imaging in inflammatory bowel disease (IBD). Five IBD patients and 12 control subjects performing 68Ga-pentixafor PET/CT examinations were included. 68Ga-pentixafor PET/CT imaging and endoscopic findings were recorded and compared. The semiquantitative parameters of 68Ga-pentixafor uptake by the lesion segments in IBD patients and the normal intestines in the control were investigated. Among these 5 IBD patients, endoscopy successfully examined a total of 26 intestinal segments, with 13 segments showing endoscopic lesions. 68Ga-pentixafor PET/CT was positive in all endoscopy-proven lesions (13/13). Additionally, 68Ga-pentixafor PET/CT revealed the lesions in small intestines and colons that cannot be reached by endoscopy due to severe stenosis, and mesenteric lymphadenitis accompanied IBD. The SUVmax of the lesion segments in IBD patients was significantly higher than that of the normal intestines in the control group (median, 3.15 [range, 1.61-6.26] vs 1.67 [1.18-2.29], P < 0.001). Moreover, the SUVmax ratios of the lesion segments/liver or blood pool were higher when compared with the control (2.20 [1.13-3.26] vs 0.85 [0.54-1.20]; 1.66 [0.94-2.95] vs 0.67 [0.52-1.04]; P ≤ 0.001). 68Ga-pentixafor PET/CT can be a potentially valuable tool to assess the active intestinal lesions of IBD with high sensitivity. Moreover, this noninvasive approach does not require fasting or bowel preparation, offering good tolerance and safety.

Review of whole-body magnetic resonance imaging in multiple myeloma.

Multiple Myeloma (MM) is a hematological malignancy affecting bone marrow, most frequently in elderly men. Imaging has a crucial role in this disease. Recently, whole-body MRI has been introduced and it has gained growing interest due to is high sensitivity and specificity in evaluating bone marrow involvement in MM. Diffusion-weighted sequences (DWI) with apparent diffusion coefficient (ADC) maps have emerged as the most sensitive technique to evaluate patients with MM, both in the pre- and post-treatment setting. Aim of this review is to provide an overview of the role and main imaging findings of whole-body MRI in MM.

Differentiating idiopathic inflammatory myopathies by automated morphometric analysis of MHC-1, MHC-2 and ICAM-1 in muscle tissue.

Diagnosis of idiopathic inflammatory myopathies (IIM) is based on morphological characteristics and the evaluation of disease-related proteins. However, although broadly applied, substantial bias is imposed by the respective methods, observers and individual staining approaches. We aimed to quantify the protein levels of major histocompatibility complex (MHC)-1, (MHC)-2 and intercellular adhesion molecule (ICAM)-1 using an automated morphometric method to mitigate bias. Double immunofluorescence staining was performed on whole muscle sections to study differences in protein expression in myofibre and endomysial vessels. We analysed all IIM subtypes including dermatomyositis (DM), anti-synthetase syndrome (ASyS), inclusion body myositis (IBM), immune-mediated-necrotising myopathy (IMNM), dysferlinopathy (DYSF), SARS-CoV-2 infection and vaccination-associated myopathy. Biopsies with neurogenic atrophy (NA) and normal morphology served as controls. Bulk RNA-Sequencing (RNA-Seq) was performed on a subset of samples. Our study highlights the significance of MHC-1, MHC-2 and ICAM-1 in diagnosing IIM subtypes and reveals distinct immunological profiles. RNASeq confirmed the precision of our method and identified specific gene pathways in the disease subtypes. Notably, ASyS, DM and SARS-CoV-2-associated myopathy showed increased ICAM-1 expression in the endomysial capillaries, indicating ICAM-1-associated vascular activation in these conditions. In addition, ICAM-1 showed high discrimination between different subgroups with high sensitivity and specificity. Automated morphometric analysis provides precise quantitative data on immune-associated proteins that can be integrated into our pathophysiological understanding of IIM. Further, ICAM-1 holds diagnostic value for the detection of IIM pathology.

Temperature-insensitive vector curvature sensor based on four-core fiber offset structure

Vector curvature measurement is very important in industrial fields with the unavoidable problem of temperature crosstalk. To improve the detection performance, a novel temperature-insensitive vector bending sensor have been proposed in the paper. The sensor is fabricated by core-offset splicing a segment of four-core fiber (FCF) between two single-mode fibers (SMFs). The Mach-Zehnder interference and the recognition ability of bending directions are enhanced by the core-offset structure. The experimental results demonstrate the curvature sensitivities of our sensor reach 38.16 nm/m−1, 37.46 nm/m−1, 4.99 nm/m−1 and −7.12 nm/m−1 in different bending directions within the range of 0.346–0.49 m−1. The average temperature sensitivity is only −6.67 pm/℃ in the range of 30–90 °C. The all-fiber, low cost, high sensitivity, and excellent vectoriality make our sensor more potential in harsh, complex industrial environment.

Broadband Enhancement of Magneto-Optical Effects in Hybrid Waveguide-Plasmonic Surfaces for Sensing.

Conventional magnetophotonic nanostructures typically function within narrow wavelength and incident angle ranges, where resonance is observed and magneto-optical (MO) effects are amplified. Expanding these operational ranges may allow for improved applications, including in (bio)sensing devices. In this study, we describe a hybrid magnetoplasmonic waveguide grating (HMPWG) in which the coupling of plasmonic resonances and waveguide modes leads to enhanced MO effects and sensitivity, according to full-wave electromagnetic simulations. High transverse magneto-optical Kerr effect (TMOKE) signals were observed for the full range of wavelengths and angles investigated, i.e., for θinc ≥ 1° and 500 nm ≤ λ ≤ 850 nm. As a proof-of-concept we verified that using the HMPWG nanostructure with an aqueous solution as superstrate one may obtain a sensitivity in variation of the refractive index unit (RIU) of S = 166°/RIU and S = 230 nm/RIU in angle and wavelength interrogation modes, respectively. Upon comparing with conventional magnetoplasmonic gratings, which only enable excitation of plasmonic resonances, we demonstrate that HMPWG nanostructures can be further optimized to reach not only high sensitivity but also high resolution in sensing and biosensing.

Magnetic resonance imaging of the breast: Could it be used as a screening test?

To investigate whether magnetic resonance imaging (MRI) best detects early malignancy in high-risk women. A retrospective, cross-sectional study, carried out at King Abdulaziz University Hospital, Jeddah, Saudi Arabia, included 419 female breast cancer patients aged 16-84 years (mean age of 49). Data were collected from the radiological department's database to compare the MRI, ultrasound (US), and mammography results, with or without tissue biopsy. In diagnosing benign versus malignant lesions, MRI showed significant agreement with tissue biopsy, with high sensitivity (70%) and specificity (87%); its positive predictive value (PPV) was 92% and negative predictive value (NPV) was 56%. While US has a PPV of 84% and NPV of 63%; with a sensitivity (79%) and specificity (71%). In patients without tissue biopsy, there was little difference between mammography and US compared with MRI results. Magnetic resonance imaging is more effective than US and mammography for early detection of BC. It showed high sensitivity in detecting breast lesions and high specificity in characterizing their nature when correlated with pathological results. Ultrasound screening followed by MRI is suggested for undetected or suspected lesions. This will increase the breast lesion detection rate, reduce unneeded tissue biopsies, and enhance the disease's survival rate.

Single-molecule epiallelic profiling of DNA derived from routinely collected Pap specimens for noninvasive detection of ovarian cancer.

Recent advances in molecular analyses of ovarian cancer have revealed a wealth of promising tumour-specific biomarkers, including protein, DNA mutations and methylation; however, reliably detecting such alterations at satisfactorily high sensitivity and specificity through low-cost methods remains challenging, especially in early-stage diseases. Here we present PapDREAM, a new approach that enables detection of rare, ovarian-cancer-specific aberrations of DNA methylation from routinely-collected cervical Pap specimens. The PapDREAM approach employs a microfluidic platform that performs highly parallelized digital high-resolution melt to analyze locus-specific DNA methylation patterns on a molecule-by-molecule basis at or near single CpG-site resolution at a fraction (<1/10th) of the cost of next-generation sequencing techniques. We demonstrate the feasibility of the platform by assessing intermolecular heterogeneity of DNA methylation in a panel of methylation biomarker loci using DNA derived from Pap specimens obtained from a cohort of 43 women, including 18 cases with ovarian cancer and 25 cancer-free controls. PapDREAM leverages systematic multidimensional bioinformatic analyses of locus-specific methylation heterogeneity to improve upon Pap-specimen-based detection of ovarian cancer, demonstrating a clinical sensitivity of 50% at 99% specificity in detecting ovarian cancer cases with an area under the receiver operator curve of 0.90. We then establish a logistic regression model that could be used to identify high-risk patients for subsequent clinical follow-up and monitoring. The results of this study support the utility of PapDREAM as a simple, low-cost screening method with the potential to integrate with existing clinical workflows for early detection of ovarian cancer. KEY POINTS: We present a microfluidic platform for detection and analysis of rare, heterogeneously methylated DNA within Pap specimens towards detection of ovarian cancer. The platform achieves high sensitivity (fractions <0.00005%) at a suitably low cost (∼$25) for routine screening applications. Furthermore, it provides molecule-by-molecule quantitative analysis to facilitate further study on the effect of heterogeneous methylation on cancer development.

Texture-based morphometry in relation to apolipoprotein ε4 genotype, ageing and sex in a midlife population.

Brain atrophy and cortical thinning are typically observed in people with Alzheimer's disease (AD) and, to a lesser extent, in those with mild cognitive impairment. In asymptomatic middle-aged apolipoprotein ε4 (ΑPOE4) carriers, who are at higher risk of future AD, study reports are discordant with limited evidence of brain structural differences between carriers and non-carriers of the ε4 allele. Alternative imaging markers with higher sensitivity at the presymptomatic stage, ideally quantified using typically acquired structural MRI scans, would thus be of great benefit for the detection of early disease, disease monitoring and subject stratification. In the present cross-sectional study, we investigated textural properties of T1-weighted 3T MRI scans in relation to APOE4 genotype, age and sex. We pooled together data from the PREVENT-Dementia and ALFA studies focused on midlife healthy populations with dementia risk factors (analysable cohort: 1585 participants; mean age 56.2 ± 7.4 years). Voxel-based and texture (examined features: contrast, entropy, energy, homogeneity) based morphometry was used to identify areas of volumetric and textural differences between APOE4 carriers and non-carriers. Textural maps were generated and were subsequently harmonised using voxel-wise COMBAT. For all analyses, APOE4, sex, age and years of education were used as model predictors. Interactions between APOE4 and age were further examined. There were no group differences in regional brain volume or texture based on APOE4 carriership or when age × APOE4 interactions were examined. Older people tended to have a less homogeneous textural profile in grey and white matter and a more homogeneous profile in the ventricles. A more heterogeneous textural profile was observed for females in areas such as the ventricles, frontal and parietal lobes and for males in the brainstem, cerebellum, precuneus and cingulate. Overall, we have shown the absence of volumetric and textural differences between APOE4 carriers and non-carriers at midlife and have established associations of textural features with ageing and sex.

Inflammatory markers in systemic immune-inflammatory index and inflammatory response index to predict early pregnancy loss.

To uncover the predictive value of systemic immune-inflammatory index (SII) and systemic inflammatory response index (SIRI) on early pregnancy loss. A total of 535 individuals were enrolled in this retrospective analysis. The early pregnancy losses (EPL) group included patients between 18-35 years old who experienced EPL. The control group comprised healthy pregnant women who gave birth at ≥37 weeks. The EPL group had significantly lower plateletcrit (p=0.04), platelet distribution width (PDW, p<0.0001), and RDW (p<0.0001) and higher monocyte (p<0.0001) and SIRI (p<0.0001) values than the control group. The hemoglobin, white blood cells, platelet count, neutrophil count, lymphocyte count, mean platelet volume, neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), and SII values were not significantly different between the EPL and control groups (p>0.05). The cut-off value for the SIRI that offers the best sensitivity/specificity balance was 1.48 (sensitivity of 63%; specificity of 63%) in the receiver operating characteristics curve. Among the inflammatory parameters for predicting EPL, PDW had highest specificity (84%), and RDW had the highest sensitivity (80%). This study provides compelling evidence that various inflammatory pathways may significantly contribute to EPL pathogenesis. Moreover, our findings suggest that SIRI could be a more effective marker than NLR, PLR, MLR, and SII in predicting EPL in an ongoing pregnancy, thereby potentially revolutionizing early pregnancy loss diagnostics.

Predictive capacity of fetal pancreatic circumference for gestational diabetes mellitus.

To assess the capacity of fetal pancreatic size, before standard blood testing for screening and diagnosis, to predict maternal gestational diabetes mellitus (GDM). This was a retrospective cohort study of low-risk pregnant women recruited during routine second-trimester fetal anatomical screening at 20-25 weeks' gestation at two ultrasound units in Israel between 2017 and 2020. The predictive performance of fetal pancreatic circumference ≥ 80th and ≥ 90th centiles and glucose challenge test (GCT) was examined for the outcome of GDM. The independent-samples t-test was used to compare mean pancreatic circumference centile between pregnancies with GDM and those without GDM. Diagnostic performance was evaluated with 2 × 2 contingency tables and receiver-operating-characteristics (ROC) curves. Overall, 195 women were selected for statistical analysis. Twenty-four (12.3%) women were diagnosed subsequently with GDM. The mean ± SD pancreatic circumference centile was significantly higher in the GDM group compared with the non-GDM group (82.4 ± 14.6 vs 62.8 ± 27.6; P < 0.001). The pancreatic circumference centile was correlated positively with the estimated fetal weight centile (Pearson's coefficient, 0.243; P = 0.001). The 80th centile cut-off for pancreatic circumference had the highest sensitivity (70.8%) and positive predictive value (23.3%) for future maternal GDM, with the best trade-off between sensitivity and specificity achieved at the 75th centile cut-off (sensitivity, 79%; specificity, 60%). The GCT had better specificity (90.2%) and negative predictive value (97.9%) compared with both cut-offs in pancreatic circumference. The area under the ROC curve was higher for pancreatic circumference compared with GCT (0.71 vs 0.64) and only the former was statistically significant (P = 0.001). Fetal pancreatic circumference has a higher positive predictive capacity compared with GCT. Measuring pancreatic circumference can identify pregnancies at high risk for maternal GDM, thereby promoting earlier diagnosis and treatment, decreasing the time period during which the fetus is exposed to high maternal glucose levels and improving infant outcome. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Imaging of Biliary Tree Abnormalities.

Pathologic conditions of the biliary system, although common, can be difficult to diagnose clinically. Challenges in biliary imaging include anatomic variants and the dynamic nature of the biliary tract, which can change with age and intervention, blurring the boundaries of normal and abnormal. Choledochal cysts can have numerous appearances and are important to diagnose given the risk of cholangiocarcinoma potentially requiring surgical resection. Choledocholithiasis, the most common cause of biliary dilatation, can be difficult to detect at US and CT, with MRI having the highest sensitivity. However, knowledge of the imaging pitfalls of MRI and MR cholangiopancreatography is crucial to avoid misinterpretation. Newer concepts in biliary tract malignancy include intraductal papillary biliary neoplasms that may develop into cholangiocarcinoma. New paradigms in the classification of cholangiocarcinoma correspond to the wide range of imaging appearances of the disease and have implications for prognosis. Accurately staging cholangiocarcinoma is imperative, given expanding curative options including transplant and more aggressive surgical options. Infections of the biliary tree include acute cholangitis or recurrent pyogenic cholangitis, characterized by obstruction, strictures, and central biliary dilatation. Inflammatory conditions include primary sclerosing cholangitis, which features strictures and fibrosis but can be difficult to differentiate from secondary causes of sclerosing cholangitis, including more recently described entities such as immunoglobulin G4-related sclerosing cholangitis and COVID-19 secondary sclerosing cholangitis. The authors describe a wide variety of benign and malignant biliary tract abnormalities, highlight differentiating features of the cholangitides, provide an approach to interpretation based on the pattern of imaging findings, and discuss pearls and pitfalls of imaging to facilitate accurate diagnosis. ©RSNA, 2024 Supplemental material is available for this article.

Diagnostic accuracy of digital breast tomosynthesis and digital mammography in women with dense or non-dense breast tissue: A systematic review and meta-analysis.

Despite its excellent screening effectiveness and sensitivity for breast cancer (BC), digital breast tomosynthesis (DBT) is controversial due to its high radiation exposure and long reading time. This study examines the diagnostic accuracy of DBT and digital mammography (DM) for BC screening and diagnosis in women with dense or non-dense breast tissue. PRISMA-compliant searches were performed on Medline, Embase, PubMed, Web of Science, and the Cochrane databases for articles comparing DBT and DM for BC screening until March 2023. Meta-analysis was performed using RevMan sofware, and the Cochrane Risk of Bias Assessment Tool was employed to assess study quality. This meta-analysis included 11 trials with a total of 2,124,018 individuals. Screening with DBT resulted in a greater cancer detection rate, as demonstrated by a risk ratio (RR) of 1.27 (95% confidence interval (95% CI): 1.14-1.41). Digital breast tomosynthesis also had a reduced recall rate, with a RR of 0.88 (95% CI: 0.78-0.99), higher sensitivity and specificity values (pooled sensitivity of 0.91 (95% CI: 0.59-0.99)) and pooled specificity of 0.90 (95% CI: 0.42-1.0)) than DM (pooled sensitivity of 0.86 (95% CI: 0.52-1.0) and pooled specificity of 0.81 (95% CI: 0.12-1.0)). All acquired data exhibited reliability, lack of bias and statistical significance (p < 0.05). Digital breast tomosynthesis is a more effective screening and diagnostic assessment tool for women with dense or non-dense breasts than DM in terms of incremental cancer detection, sensitivity and recall rate.

Development of classical swine fever virus E2-protein based indirect ELISA for detection of antibodies against the virus in pigs.

Classical swine fever (CSF) is an economically important and highly contagious disease of pigs caused by CSF virus, genus Pestivirus. Serological diagnosis of the disease is highly valuable for surveillance and thereby containment of spread of the disease. In this study, we have demonstrated the development of CSFV envelope glycoprotein E2-based indirect ELISA (E2-iELISA) for the detection of CSFV specific antibodies. The full-length E2 protein was expressed in E. coli and the purified protein was used as a coating antigen in indirect ELISA for detecting CSFV specific antibodies in pigs. A panel of 506 pig sera samples was used to validate the ELISA and the results were highly comparable to the results obtained with the commercial antibody detection kit (PrioCHECK CSFV Ab kit). The in-house E2-iELISA demonstrated high diagnostic sensitivity (95.4%) and specificity (95.5%), highlighting its potential application for sero-surveillance or monitoring of the disease in the swine population.

Structural and biochemical characterization of an encapsulin-associated rhodanese from Acinetobacter baumannii.

Rhodanese-like domains (RLDs) represent a widespread protein family canonically involved in sulfur transfer reactions between diverse donor and acceptor molecules. RLDs mediate these transsulfuration reactions via a transient persulfide intermediate, created by modifying a conserved cysteine residue in their active sites. RLDs are involved in various aspects of sulfur metabolism, including sulfide oxidation in mitochondria, iron-sulfur cluster biogenesis, and thio-cofactor biosynthesis. However, due to the inherent complexity of sulfur metabolism caused by the intrinsically high nucleophilicity and redox sensitivity of thiol-containing compounds, the physiological functions of many RLDs remain to be explored. Here, we focus on a single domain Acinetobacter baumannii RLD (Ab-RLD) associated with a desulfurase encapsulin which is able to store substantial amounts of sulfur inside its protein shell. We determine the 1.6 Å x-ray crystal structure of Ab-RLD, highlighting a homodimeric structure with a number of unusual features. We show through kinetic analysis that Ab-RLD exhibits thiosulfate sulfurtransferase activity with both cyanide and glutathione acceptors. Using native mass spectrometry and in vitro assays, we provide evidence that Ab-RLD can stably carry a persulfide and thiosulfate modification and may employ a ternary catalytic mechanism. Our results will inform future studies aimed at investigating the functional link between Ab-RLD and the desulfurase encapsulin.

Evaluation of an AI algorithm trained on an ethnically diverse dataset to screen a previously unseen population for diabetic retinopathy.

This study aimed to determine the generalizability of an artificial intelligence (AI) algorithm trained on an ethnically diverse dataset to screen for referable diabetic retinopathy (RDR) in the Armenian population unseen during AI development. This study comprised 550 patients with diabetes mellitus visiting the polyclinics of Armenia over 10 months requiring diabetic retinopathy (DR) screening. The Medios AI-DR algorithm was developed using a robust, diverse, ethnically balanced dataset with no inherent bias and deployed offline on a smartphone-based fundus camera. The algorithm here analyzed the retinal images captured using the target device for the presence of RDR (i.e., moderate non-proliferative diabetic retinopathy (NPDR) and/or clinically significant diabetic macular edema (CSDME) or more severe disease) and sight-threatening DR (STDR, i.e., severe NPDR and/or CSDME or more severe disease). The results compared the AI output to a consensus or majority image grading of three expert graders according to the International Clinical Diabetic Retinopathy severity scale. On 478 subjects included in the analysis, the algorithm achieved a high classification sensitivity of 95.30% (95% CI: 91.9%-98.7%) and a specificity of 83.89% (95% CI: 79.9%-87.9%) for the detection of RDR. The sensitivity for STDR detection was 100%. The study proved that Medios AI-DR algorithm yields good accuracy in screening for RDR in the Armenian population. In our literature search, this is the only smartphone-based, offline AI model validated in different populations.