Significant Change In Sensitivity Research Articles

Changes in Reader Performance During Sequential Reading of Breast Cancer Screening Digital Breast Tomosynthesis Examinations.

Background Studies suggest that readers experience perceptual adaptation when interpreting batched screening mammograms, which may serve as a mechanism for improved performance. Purpose To analyze clinical digital breast tomosynthesis (DBT) screening data to evaluate changes in reader performance during sequential batch reading. Materials and Methods This observational retrospective study used data from the radiology information system collected for screening DBT examinations performed from January 2018 to December 2019. The reference standard was established based on pathology results, if applicable, or imaging findings at 1-year follow-up. Examinations were aggregated into batches, defined as a sequence of cases for a given reader with differences in interexamination time of 10 minutes or less. Mixed-effect models were used to evaluate performance and timing across batch positions. Statistical adjustments accounted for potential confounders, including patient characteristics (age, breast density), reading factors (day of week, time of day), and between-reader heterogeneity. Results The dataset included 121 652 examinations (median patient age, 61 years [IQR, 53-69 years]), including 1081 cancers interpreted by 15 radiologists. Unadjusted false-positive rates decreased from an averaged 15.5% at the first within-batch examination to 10.5% after three sequentially read examinations (P < .001), without a significant change in sensitivity (82.6% vs 84.2%; P = .15). The interpretation time consistently decreased, achieving a substantial reduction in longer batches (average 2.8 to 2.2 minutes for noncancer examinations; P < .001). Adjustment for sampling bias and confounders (patient age, breast density, day of week, time of day; all P < .005) reduced the effect on false-positive rates (11.5% to 9.4% after three examinations; P < .001) and interpretation time (3.2 to 2.7 minutes for noncancer examinations; P < .001). Conclusion Radiologists showed improved recall rates and interpretation times without change in sensitivity over the course of batch reading of DBT screening examinations. © RSNA, 2024 See also the editorial by Iima and Satake in this issue.

Clinical applicability of signal heterogeneity and tumor border assessment on T2-weighted MR images to distinguish astrocytic from oligodendroglial origin of gliomas

Background and purposeRadiological features on magnetic resonance imaging (MRI) were attributed to oligodendroglioma, although the diagnostic accuracy in a real-world clinical setting remains partially elusive. This study investigated the accuracy and robustness of tumor heterogeneity and tumor border delineation on T2-weighted MRI to distinguish oligodendroglioma from astrocytoma. Materials and methodsEight readers from three different specialties (radiology, neurology, neurosurgery) with varying levels of experience blindly rated 79 T2-weighted MR images of patients with either oligodendroglioma or astrocytoma. After the first reading session, all readers were re-invited for a second reading session within three weeks. Diagnostic accuracy, including area under the receiver operator characteristics curve (AUC), and intra-observer variability and inter-observer variability were used as outcome measures. ResultsPooled sensitivity and specificity to distinguish oligodendroglioma from astrocytoma for the use of tumor heterogeneity were 59.9 % respectively 74.5 %, and 85.7 % respectively 40.1 % for tumor border. A second reading session did not result in a significant change in sensitivity or specificity for tumor heterogeneity (P = 0.752 and P = 0.733, respectively) or tumor border (P = 0.309 and P = 0.271, respectively). An AUC of 0.825 was achieved with regard to predicting oligodendroglial origin of gliomas. Intra-observer agreement ranged from moderate to very good for tumor heterogeneity (kappa-value 0.43–0.87) and tumor border (0.40–0.84). A moderate inter-oberserver agreement was achieved for tumor heterogeneity and tumor border (kappa-value of 0.50 and 0.45, respectively). ConclusionThis study demonstrates that tumor heterogeneity and tumor borders on T2-weighted MRI could be used with moderate Finter-observer agreement to non-invasively distinguish oligodendroglioma from astrocytoma.

Fatigue and vigilance in medical experts detecting breast cancer

An abundance of laboratory-based experiments has described a vigilance decrement of reducing accuracy to detect targets with time on task, but there are few real-world studies, none of which have previously controlled the environment to control for bias. We describe accuracy in clinical practice for 360 experts who examined >1 million women's mammograms for signs of cancer, whilst controlling for potential biases. The vigilance decrement pattern was not observed. Instead, test accuracy improved over time, through a reduction in false alarms and an increase in speed, with no significant change in sensitivity. The multiple-decision model explains why experts miss targets in low prevalence settings through a change in decision threshold and search quit threshold and propose it should be adapted to explain these observed patterns of accuracy with time on task. What is typically thought of as standard and robust research findings in controlled laboratory settings may not directly apply to real-world environments and instead large, controlled studies in relevant environments are needed.

Incremental value of diffusion weighted imaging over conventional MRI for the diagnosis of osteomyelitis of extremities.

To determine the incremental value of diffusion weighted imaging (DWI) over conventional MR imaging in diagnosing extremity osteomyelitis (OM). In this cross-sectional study, three experienced musculoskeletal radiologists evaluated clinically suspected cases of extremity OM in two rounds-first on conventional MR imaging, and then conventional MR imaging combined with DWI 4-6 weeks later. The readers recorded a result of the presence or absence of OM and their diagnostic confidence on a 1-5 scale. Mean and minimum apparent diffusion coefficient (ADC) were measured. Pathology diagnosis served as the reference standard. Statistical analysis utilized intraclass correlation (ICC) and Conger's kappa. A total of 213 scans of suspected OM were reviewed by three musculoskeletal radiologists with no significant changes in sensitivity (0.97, 0.97), specificity (0.97, 0.94), positive predictive value (0.91, 0.87), or negative predictive value (0.98, 0.98) between conventional MR imaging and MR imaging combined with DWI, respectively. Reader confidence did not significantly change with the addition of DWI (4.55 and 4.70, respectively). A high inter-reader agreement was observed for the diagnosis of OM, soft tissue abscess, and intraosseous abscess in both rounds. A higher mean (1.46+/-0.43 × 10-3 mm2/s > 0.64+/-0.47 × 10-3mm2/s) and minimum (1.18+/-0.45 × 10-3mm2/s > 0.37+/-0.44 × 10-3mm2/s) ADC value was associated with OM (p-value < 0.0001) with odds ratios of 1.34 and 1.31, respectively, for mean and minimum ADC of the involved bone. DWI-derived ADC increase is associated with OM. The use of DWI slightly increases reader confidence in the diagnosis of OM; however, no significant incremental value over conventional MR imaging is seen for the final diagnosis of OM.

No-core fiber by self-image length optimization for optical based refractive index sensor

No-core fiber has been widely demonstrated as an alternative refractive index sensor over conventional optical fiber sensors. However, previous works demonstrated that the self-image length optimization of this sensor only focused on simulation and formed a conclusion without data analysis. Hence, the sensitivity provided does not follow the standard unit, providing a limited evaluation of the sensitivity for refractive index measurement. This paper investigates the no-core fiber at a fixed diameter of 125 μm and varies the length based on the self-image index ranging from 1 to 4 indexes to evaluate the sensor sensitivity at the analyte refractive index ranging from 1.3000 RIU to 1.4000 RIU via experimental study. The results showed that the dip wavelength shift non-linearly increased for all the samples as the analyte refractive index increased. The overall analysis showed that there were significant changes in the sensitivity between the odd and even self-image indexes, and there were no significant sensitivity changes between them. The best sensor performance was achieved by the NCF length of 2.90 cm with two self-image indexes. The sensitivity achieved by the sensor was 104.64 nm/RIU and 241.30 nm/RIU for analyte refractive index ranging from 1.3000 RIU to 1.3600 RIU and 1.36000 RIU to 1.4000 RIU, respectively, via a linear fitting plot. Meanwhile, the figure merit value obtained by the sensor was 1.45 RIU−1 and 3.75 RIU−1 at analyte RI of 1.3600 RIU and 1.4000 RIU, respectively. In the future, this can be used as a reference for no core fiber length optimization.

Development of potentiometric sensors based on thiourea derivatives, Gd2O3@rGO and MoO3@rGO for the determination of salicylate in drug tablets and biofluids and DFT studies

Determination of salicylates in pharmaceutical formulations and biofluids is of great importance because of the toxicity of high doses in the blood. However, most analytical methods used for salicylate determination are expensive and time-consuming. In this study, potentiometric sensors based on carbon paste electrodes (CPEs) with the thiourea derivative (TUD1, ionophore) were successfully constructed for the detection of salicylate levels in pharmaceutical formulations and biofluids. Computational studies at the density functional theory (DFT) level were utilized to estimate inter-and intra-molecular interactions between salicylate and TUD1. The sensitivity of the CPEs to salicylate ions was optimized using different plasticizers (2-nitrophenyloctyl ether-NPOE, tricresyl phosphate-TCP, and dibutyl phthalate-DPB), nanomaterials (Gd2O3@rGO and MoO3@rGO), and ion exchanger (tridodecylmethylammonium chloride-TDMAC). The use of nanomaterials (Gd2O3@rGO and MoO3@rGO) improved the sensitivity and response time of the sensor over a wide pH range (4–10). The best sensor achieved a Nernst slope of 60 mV/decade over a dynamic concentration of 10−5 to 10−1 M with a detection limit of 10−5 M and good selectivity to interfering ions (Cl−, F−, Br−, benzoate, uric acid, and ascorbic acid) compared to previous reports. In addition, the sensor exhibited a lifetime of 6 months without any significant change in sensitivity (less than 5 % deviation). The developed sensors were successfully used for the determination of salicylate in tablets (Aspocid®), spiked serum, and spiked urine with high accuracy.

Diagnostic accuracy of cervical cancer screening strategies for high-grade cervical intraepithelial neoplasia (CIN2+/CIN3+) among women living with HIV: A systematic review and meta-analysis.

SummaryBackgroundWe systematically reviewed the diagnostic accuracy of cervical cancer screening and triage strategies in women living with HIV (WLHIV).MethodsCochrane Library, Embase, Global Health and Medline were searched for randomised controlled trials, prospective or cross-sectional studies published from database inception to 15 July 2022 reporting diagnostic accuracy of tests in cervical cancer screening and triage of screen-positive WLHIV. Studies were included if they reported the diagnostic accuracy of any cervical cancer screening or triage strategies for the detection of histologically-confirmed high-grade cervical intraepithelial neoplasia (CIN2+/CIN3+) among WLHIV. Summary data were extracted from published reports. Authors were contacted for missing data where applicable. Sensitivity and specificity estimates for CIN2/3+ were pooled using models for meta-analysis of diagnostic accuracy data. Study quality was assessed using the QUADAS-2 tool for the quality assessment of diagnostic accuracy studies. PROSPERO registration:CRD42020189031.FindingsIn 38 studies among 18,737 WLHIV, the majority (n=19) were conducted in sub-Saharan Africa. The pooled prevalence was 12.0% (95%CI:9.8-14.1) for CIN2+ and 6.7% (95%CI:5.0-8.4) for CIN3+. The proportion of screen-positive ranged from 3-31% (visual inspection using acetic acid[VIA]); 2-46% (high-grade squamous intraepithelial lesions, and greater [HSIL+] cytology); 20-64% (high-risk[HR]-HPV DNA). In 14 studies, sensitivity and specificity of VIA were variable limiting the reliability of pooled estimates. In 5 studies where majority had histology-confirmed CIN2+, pooled sensitivity was 56.0% (95%CI:45.4-66.1; I2=65%) for CIN2+ and 65.0% (95%CI:52.9-75.4; I2=42%) for CIN3+; specificity for <CIN2 was 73.8% (95%CI:59.8-84.2, I2=94%). Cytology was similarly variable (sensitivity of ASCUS+ for CIN2+ range: 58-100%; specificity: 9-96%). In 28 studies, sensitivity of tests targeting 14-HR-HPV types was high (91.6%, 95%CI:88.1-94.1; I2=45% for CIN2+ and 92.5%, 95%CI:88.4-95.2; I2=32%) for CIN3+); but specificity for <CIN2 was low (62.2% (95%CI:57.9-66.4;I2=92%). Restriction to 8-HR-HPV increased specificity (65.8%; Relative specificity[RSpec] vs. 14-HR-HPV=1.17; 95%CI:1.10-1.24) with no significant change in sensitivity (CIN2+:85.5%; Relative Sensitivity[RSens]=0.94, 95%CI: 0.89-1.00; CIN3+:90%; RSens=0.96, 95%CI:0.89-1.03). VIA triage of 14-HR-HPV positive women decreased sensitivity for CIN2+ compared to HPV-DNA test alone (64.4% vs. 91.6%; RSens=0.68, 95%CI:0.62-0.75).InterpretationHPV-DNA based approaches consistently showed superior sensitivity for CIN2+/CIN3+ compared to VIA or cytology. The low specificity of HPV-DNA based methods targeting up to 14-HR-HPV could be improved significantly by restricting to 8-HR-HPV with only minor losses in sensitivity, limiting requirement for triage for which optimal approaches are less clear.FundingWorld Health Organisation; National Cancer Institute; European Union's Horizon 2020 and Marie Skłodowska-Curie Actions programme.

Impact of Obtaining a Digital Breast Tomosynthesis (DBT) Spot Compression View on Assessment of Equivocal DBT Findings.

BACKGROUND. A recently introduced digital breast tomosynthesis (DBT) device allows acquisition of DBT spot compression views with a small paddle during DBT acquisition. OBJECTIVE. The purpose of this study was to evaluate the impact on diagnostic performance of obtaining a DBT spot compression view for assessment of equivocal DBT findings. METHODS. This retrospective study included 102 women (mean age, 60 years) in whom a DBT spot compression view was obtained to characterize an equivocal finding on DBT at the performing radiologist's discretion. The DBT examinations were performed from December 14, 2018, to December 18, 2019. Two fellowship-trained breast radiologists and one breast imaging fellow, who were aware of the location of the equivocal lesions, independently reviewed the examinations. Readers first assigned a BI-RADS category using standard DBT views and then immediately assigned a category using the DBT spot compression view. BI-RADS categories 2 and 3 were considered negative, and categories 4A and greater were considered positive. Histology and at least 1 year of imaging follow-up served as the reference standard. Intrareader agreement for one reader and interreader agreement among all readers were evaluated with kappa coefficients. Diagnostic performance was compared between DBT with and DBT without spot compression views by use of McNemar tests. RESULTS. Intrareader agreement increased from 0.43 to 0.72, and interreader agreement increased from 0.21 to 0.45 on the basis of kappa coefficients for DBT without and with spot compression views. Eighteen cancers were present. Compared with standard DBT views, DBT spot compression views yielded significantly increased accuracy for all three readers (75% vs 90%, 74% vs 94%, 72% vs 94%); significantly increased specificity for all three readers (69% vs 90%, 75% vs 94%, 68% vs 93%); and significantly increased sensitivity for one reader (67% vs 94%) without significant change in sensitivity for the two other readers (89% vs 100%, 100% vs 89%). Radiation dose was 1.97 mGy for the DBT spot compression view versus 1.78-1.81 mGy for standard DBT craniocaudal and medio-lateral oblique views. CONCLUSION. Use of the DBT spot compression view increased intrareader agreement, interreader agreement, and diagnostic accuracy (primarily owing to improved specificity); the supplemental dose for the spot compression view was slightly higher than that for a standard DBT view. CLINICAL IMPACT. DBT spot compression may help characterize equivocal DBT findings, reducing further workup for benign findings.

Exploring the application of blue and red thermoluminescence for dating volcanic glasses

Tephras are significant markers in the stratigraphic record and play a key role in establishing paleoenvironmental and paleoclimate histories worldwide. Despite burgeoning research focused on tephra characterization and correlation techniques, there are still few techniques that allow for the direct dating of tephra, particularly below the lower age limit of K/Ar and Ar/Ar dating methods. In this study, we test different thermoluminescence (TL) dating approaches on the 4–11 μm volcanic glass constituents of three different independently different tephras. By comparing against independent age control, we demonstrate the utility of both blue (320–450 nm) and red (587–651 nm) TL emissions for dating volcanic glasses using single aliquot regenerative (SAR) dose techniques. We find that both blue and red TL emissions from the volcanic glass shards are dim but reproducible and show no evidence for significant sensitivity changes occurring between the natural TL and the first test dose during the SAR protocol. Fading tests on the blue TL signal show that g-values range from 1.6 ± 1.0 to 2.9 ± 1.1%/decade and are statistically indistinguishable with zero at 2σ for the red TL. Bleaching experiments show that both blue and red TL signals are sensitive to light exposure, with sensitivity corrected signals declining by ∼40% over a 2-h period. For all three tephras, both the fading-corrected blue and red SAR-TL ages are consistent with age expectation. These successful results demonstrate the effectiveness of TL techniques for determining the eruption ages of tephra deposits in primary position between ∼1 and at least 30 ka.

Role of Contrast-enhanced Ultrasound in Distinguishing between Benign and Malignant Thyroid Nodules with Calcification

Objective To explore the roles of conventional ultrasound and contrast-enhanced ultrasound in distinguishing between benign and malignant thyroid nodules with calcification. Methods A total of 102 solid thyroid nodules with calcification in 76 patients were evaluated by conventional ultrasound alone and conventional ultrasound combined with contrast-enhanced ultrasound.The features obtained through conventional ultrasound alone and that combined with contrast-enhanced ultrasound were scored,and the diagnostic performance of the two methods was analyzed based on the final pathological results. Results The distribution of microcalcification(P<0.0001),aspect ratio>1(P=0.039),unclear boundary(P=0.027),ring enhancement around nodules(P=0.000),and the degree(P=0.000)and uniformity(P=0.001)of enhancement for the non-calcified part were statistically different between benign and malignant nodules.Compared with conventional ultrasound alone,conventional ultrasound combined with contrast-enhanced ultrasound significantly improved the area under the curve(0.841 vs.0.701,P<0.001)and specificity(97.06% vs. 44.12%,P=0.007),without significant change in sensitivity(67.55% vs. 73.53%,P=0.727). Conclusions The combination with contrast-enhanced ultrasound can improve the performance of conventional ultrasound in the differential diagnosis of benign and malignant thyroid solid nodules with calcification.Eight malignant signs include solid,hypoechoic,microcalcification,aspect ratio,and blurred edges detected by conventional ultrasound,and non-circular enhancement around nodules,low enhancement and non-uniform enhancement of solid parts detected by contrast-enhanced ultrasound.A solid thyroid nodule with calcification presenting five or more malignant signs highly suggests malignancy.

Diagnosing arrhythmogenic ventricular cardiomyopathy: a re-appraisal of the role and normal range of the signal-averaged ECG

Abstract Funding Acknowledgements Type of funding sources: None. Introduction The 2010 Task Force Criteria (TFC) for the diagnosis of arrhythmogenic right ventricular cardiomyopathy (A(R)VC) in 1st degree relatives includes an abnormality in a single parameter of the signal averaged ECG (SAECG). SAECG normal ranges were derived predominately from ischaemic heart disease patients, so may not be applicable in an A(R)VC population. There remain concerns that the SAECG is not specific enough and its role in the diagnosis of A(R)VC is under scrutiny. Purpose to improve the diagnostic utility of the SAECG Methods Patients with an A(R)VC diagnosis and 1st degree family members (FM) under follow-up at a single inherited cardiac conditions (ICC) centre were included. All cases were independently reviewed by 3 cardiologists experienced in the diagnosis and management of A(R)VC. All SAECGs included were free from artefact. TFC clinical variables and genetic status were recorded for each patient. Where tests had been repeated the most recent values were used. Because of concerns about the use of a single abnormal SAECG parameter in making a clinical diagnosis we required ≥2 abnormal SAECG parameters, or a confirmed genetic mutation to make a diagnosis. A diagnosis of false positive SAECG was made with ≥2 abnormalities when the individual was known not to carry the familial pathogenic mutation. Results A study population of 160 patients (male 103 (64%), age 46yrs (range 18-85yrs); 41 pro-bands and 119 FM. 62(52%) FM had a clinical diagnosis of AVC, with ARVC the pre-dominant phenotype 51(82%). A pathogenic genetic variant was identified in 24(47%) of FM with ARVC. The SAECG data is presented graphically for each parameter. A clinical diagnosis of ARVC was made on the basis of an affected 1st degree FM and an abnormal SAECG in 24(47%) of FM. Of these, 16(67%) had three abnormal SAECG parameters, 6(25%) two and 2(8%) a single abnormal parameter. Both patients with only one abnormal SAECG parameter carry a pathogenic variant. In total 88% of FM with ARVC, and 32% of FM without AVC had an abnormal SAECG as per current TFC. False positive values were mainly in fQRS duration (17/18), but also LAS40 (5/18), and RMS40 (2/18). By redefining an abnormal fQRS duration to be ≥118ms, false positives are reduced from 17 to 4. In addition, if there is a requirement for a 2nd abnormality then the false positives are reduced to 2 (4%). By adjusting the diagnostic criteria to fQRS duration ≥118ms, with a 2nd abnormal parameter or known pathogenic gene carrier status none of the 24 FM with a clinical diagnosis on abnormal SAECG alone would change diagnostic classification. Conclusion The SAECG is useful in family screening as it is frequently the only test to show an abnormality. However, the current TFC reference values lack specificity. By redefining an abnormal fQRS as ≥118ms with the requirement of a 2nd abnormal parameter, specificity is increased to 96%, with no significant change in sensitivity. Abstract Figure. SAECG Parameters in Family Members

Association between different scale bars in dermoscopic images and diagnostic performance of a market-approved deep learning convolutional neural network for melanoma recognition

BackgroundStudies systematically unravelling possible causes for false diagnoses of deep learning convolutional neural networks (CNNs) are scarce, yet needed before broader application. ObjectivesThe objective of the study was to investigate whether scale bars in dermoscopic images are associated with the diagnostic accuracy of a market-approved CNN. MethodsThis cross-sectional analysis applied a CNN trained with more than 150,000 images (Moleanalyzer-pro®, FotoFinder Systems Inc., Bad Birnbach, Germany) to investigate seven dermoscopic image sets depicting the same 130 melanocytic lesions (107 nevi, 23 melanomas) without or with digitally superimposed scale bars of different manufacturers. Sensitivity, specificity and area under the curve (AUC) of receiver operating characteristics (ROC) for the CNN's binary classification of images with or without superimposed scale bars were assessed. ResultsSix dermoscopic image sets with different scale bars and one control set without scale bars (overall 910 images) were submitted to CNN analysis. In images without scale bars, the CNN attained a sensitivity [95% confidence interval] of 87.0% [67.9%–95.5%] and a specificity of 87.9% [80.3%–92.8%]. ROC AUC was 0.953 [0.914–0.992]. Scale bars were not associated with significant changes in sensitivity (range 87%–95.7%, all p ≥ 1.0). However, four scale bars induced a decrease of the CNN's specificity (range 0%–43.9%, all p < 0.001). Moreover, ROC AUC was significantly reduced by two scale bars (range 0.520–0.848, both p ≤ 0.042). ConclusionsSuperimposed scale bars in dermoscopic images may impair the CNN's diagnostic accuracy, mostly by increasing the rate of the false-positive diagnoses. We recommend avoiding scale bars in images intended for CNN analysis unless specific measures counteracting effects are implemented. Clinical trial numberThis study was registered at the German Clinical Trial Register (DRKS-Study-ID: DRKS00013570; URL: https://www.drks.de/drks_web/).

AlN Single Crystal Accelerometer for Nuclear Power Plants

Reliable vibration sensing is essential to the immediate detection of unusual vibrations, ensuring the safety of nuclear power plant structures. For nuclear power plant applications, the sensor element must endure the harsh environment while retaining reliable performance. Aluminum nitride (AlN) single crystal is considered a promising candidate for the sensing unit due to its robustness to high temperature (HT) and irradiation conditions. However, there are few efforts in developing industrial accelerometers using AlN bulk-machined materials. This article aims to develop a shear-type accelerometer with AlN single crystal plates. The accelerometer's design is based on the numerical simulation results, followed by the fabrication of the sensor and the extensive validation under HT (~1000 °C). The sensitivity of the accelerometer was about 9.2 pC/g. The prototype sensor showed stable performance at varying temperatures from room temperature to 1000 °C. Furthermore, the sensitivity of the accelerometer was successfully sustained for 10 h under HT exposure of 1000 °C, and no obvious mechanical damage was detected after the test. After gamma irradiation for 1 month, the sensor performed stably, without any significant change in sensitivity. The developed AlN accelerometer can be a promising option to monitor the structural integrity of nuclear power plant structures.

Role of LuxR-type regulators in fish pathogenic Aeromonas hydrophila.

LuxR-type transcriptional factors are essential in many bacterial physiological processes. However, there have been no reports on their roles in Aeromonas hydrophila. In this study, six stable silent strains were constructed using shRNA. Significant decreases in the expression levels of luxR05 , luxR08 , luxR19 , luxR11 , luxR164 and luxR165 were shown in their respective strains by qRT-PCR. The luxR05 -RNAi and luxR164 -RNAi exhibit the most significant changes in sensitivity to kanamycin and gentamicin. The luxR05 -RNAi showed minimum biofilm formation and the least motility, while luxR164 -RNAi showed minimum biofilm formation, adhesion, growth and extracellular protease activity compared to the wild-type strain. In summary, the results of this paper suggest that all six luxR genes are involved in multiple physiological processes in A.hydrophila and that the roles of luxR05 and luxR164 are highly significant. The sensitivity of luxR05 -RNAi and luxR164 -RNAi to drugs may be closely related to biofilm formation. The luxR05 may play an important role in the pathogenicity of A.hydrophila by regulating the movement, adhesion and biofilm formation of bacteria, whereas luxR164 may be involved in similar functions by regulating bacterial adhesion, extracellular enzyme activity and growth. These results help further our understanding of the drug resistance and pathogenesis of A.hydrophila.

Effect of a Deep Learning Framework-Based Computer-Aided Diagnosis System on the Diagnostic Performance of Radiologists in Differentiating between Malignant and Benign Masses on Breast Ultrasonography.

ObjectiveTo investigate whether a computer-aided diagnosis (CAD) system based on a deep learning framework (deep learning-based CAD) improves the diagnostic performance of radiologists in differentiating between malignant and benign masses on breast ultrasound (US).Materials and MethodsB-mode US images were prospectively obtained for 253 breast masses (173 benign, 80 malignant) in 226 consecutive patients. Breast mass US findings were retrospectively analyzed by deep learning-based CAD and four radiologists. In predicting malignancy, the CAD results were dichotomized (possibly benign vs. possibly malignant). The radiologists independently assessed Breast Imaging Reporting and Data System final assessments for two datasets (US images alone or with CAD). For each dataset, the radiologists' final assessments were classified as positive (category 4a or higher) and negative (category 3 or lower). The diagnostic performances of the radiologists for the two datasets (US alone vs. US with CAD) were compared.ResultsWhen the CAD results were added to the US images, the radiologists showed significant improvement in specificity (range of all radiologists for US alone vs. US with CAD: 72.8–92.5% vs. 82.1–93.1%; p < 0.001), accuracy (77.9–88.9% vs. 86.2–90.9%; p = 0.038), and positive predictive value (PPV) (60.2–83.3% vs. 70.4–85.2%; p = 0.001). However, there were no significant changes in sensitivity (81.3–88.8% vs. 86.3–95.0%; p = 0.120) and negative predictive value (91.4–93.5% vs. 92.9–97.3%; p = 0.259).ConclusionDeep learning-based CAD could improve radiologists' diagnostic performance by increasing their specificity, accuracy, and PPV in differentiating between malignant and benign masses on breast US.

Confirmed value of shear wave elastography for ultrasound characterization of breast masses using a conservative approach in Chinese women: a large-size prospective multicenter trial.

PurposeThis study aimed to investigate the value of shear wave elastography (SWE) for characterization of breast masses in a Chinese population.Patients and methodsTwo thousand two hundred seventy-three women consented to be prospectively enrolled for the characterization of breast masses with ultrasound and SWE. Breast masses were known from symptoms, palpability, and/or previous imaging screening with mammography and/or ultrasound. Correlation of SWE qualitative and quantitative features with malignancy risk and impact on diagnostic performance of combining SWE features were assessed, and the Breast Imaging Reporting and Data System (BI-RADS) scoring was calculated using histopathology as reference.ResultsData of 2,262 masses (median size: 13 mm; range: 1.3–50) from 2,262 patients (median age: 43 years; range: 18–91) were investigated, of which 752 (33.3%) were malignant. Sensitivity and specificity of BI-RADS diagnosis were 97.5% (733/752) and 54.8% (827/1,510), respectively. By logistic regression, the combination of maximum elasticity (Emax) measurements with BI-RADS assessments increased the area under the receiver operating characteristic curve from 0.908 (95% CI: 0.896–0.920) to 0.954 (95% CI: 0.944–0.962). Using Emax of 30 kPa or lower to selectively downgrade BI-RADS 4a masses to follow-up, and Emax of 160 kPa or higher to selectively upgrade BI-RADS 3 lesions to biopsy, specificity significantly increased from 54.8% (827/1,510) to 66.1% (998/1,510) (P<0.001) while sensitivity decreased nonsignificantly from 97.5% (733/752) to 96.9% (729/752) (P=0.2891). Positive predictive value for biopsy recommendation increased from 51.7% (733/1,417) to 58.7% (729/1,241) (P<0.001).ConclusionAdding SWE maximum stiffness to BI-RADS 3 and BI-RADS 4a breast masses in a Chinese population increased significantly the specificity of breast ultrasonography, without significant change in sensitivity.

Education-Adjusted Normality Thresholds for FDG-PET in the Diagnosis of Alzheimer Disease

Background: A corollary of the reserve hypothesis is that what is regarded as pathological cortical metabolism in patients might vary according to education. Objective: The aim of this study is to assess the incremental diagnostic value of education-adjusted over unadjusted thresholds on the diagnostic accuracy of FDG-PET as a biomarker for Alzheimer disease (AD). Methods: We compared cortical metabolism in 90 healthy controls and 181 AD patients from the Alzheimer Disease Neuroimaging Initiative (ADNI) database. The AUC of the ROC curve did not differ significantly between the whole group and the higher-education patients or the lower-education subjects. Results: The threshold of wMetaROI values providing 80% sensitivity was lower in higher-education patients and higher in the lower-education patients, compared to the standard threshold derived over the whole AD collective, without, however, significant changes in sensitivity and specificity. Conclusion: These data show that education, as a proxy of reserve, is not a major confounder in the diagnostic accuracy of FDG-PET in AD and the adoption of education-adjusted thresholds is not required in daily practice.

Chronology of desert margin in western India using improved luminescence dating protocols

The present study provides improved chronology for the desert margin fluvial sediments of semi-arid region located in the Mahi river basin, western India. The sequence has preserved a near-continuous record of climate change since the Last Interglacial. An earlier attempt of dating based on feldspar IRSL chronology shows a combined effect of anomalous fading and unbleached components resulting in age inversions. The present work tries to explore the possibility of using blue light stimulated luminescence (BLSL) of quartz, infra-red stimulated luminescence (IRSL) of feldspar and the newly developed methodologies, like natural correction factor based single aliquot regeneration (NCF-SAR) protocol and decision making schemes based on distribution of doses and beta heterogeneity concept for luminescence dating of sediments. Observations suggest that quartz suffered from significant sensitivity changes during natural signal measurement and partial bleaching. A combination of NCF-SAR protocol and sample specific equivalent dose computation helped in arriving at better age estimate for present samples. The study also compares the criteria for the selection of different age models that are used at present. The age of the alluvial sequence is now bracketed between 10 ka (upper aeolian unit) and 75 ka (lowermost fluvial unit).

B-Mode Ultrasound Combined with Color Doppler and Strain Elastography in the Diagnosis of Non-mass Breast Lesions: A Prospective Study

Non-mass breast lesions on ultrasound (US) are areas without an associated mass. The purpose of this study was to evaluate whether combining B-mode US with color Doppler US and strain elastography (SE) improves US differentiation between benign and malignant non-mass breast lesions and the decision for biopsy. In this prospective study, three different radiologists analyzed the US images of 77 non-mass lesions independently and recorded Breast Imaging Reporting and Data System (BI-RADS) categories for four data sets. The image characteristics and BI-RADS categories of the four data sets were analyzed by another radiologist. The final diagnosis was made on the basis of pathologic findings. Values for area under the receiver operating curve (AUC), sensitivity, specificity and accuracy were compared among the data sets. The AUC of B-mode US combined with both color Doppler US and SE was greater than that of B-mode US alone (0.666 vs. 0.828) (p = 0.011). The specificity of making the decision for biopsy increased from 6.5% to 38.7% when B-mode US was combined with color Doppler and SE, without a statistically significant change in sensitivity (p < 0.001). Combined use of color Doppler and SE could improve the diagnostic value of B-mode US in distinguishing benign from malignant non-mass breast lesions and the specificity of making the decision for biopsy of non-mass breast lesions.

Application of membrane-selective electrodes for the determination of Tiemonium methylsulphate

Three ion selective electrodes were developed for the quantification of Tiemonium methylsulphate (TIM). Two of these sensors involve the construction of water insoluble ion-association complexes; namely sensor1 TIM-phosphotungstate (TIM-PT) and sensor 2 TIM-Reinecke (TIM-R). Molecular recognition elements have extensive applications in electrochemical sensors with a significant potential for future development thus a third electrode utilizing molecularly imprinted polymer was constructed; sensor 3 TIM-MIP. The proposed sensors showed fast, stable Nernstian responses of 56.4, 56.1and 57.5mV/decade for sensors 1, 2 and 3, respectively, across a relatively wide TIM concentration range (1×10−4 to 1×10−2molL−1 for sensors 1 and 2 and 1×10–5 to 1×10–2molL−1 for sensor 3) in the pH range of 2–7. Sensor 1 and sensor 2 can be used for five weeks while sensor 3 for 65days without a significant change in sensitivity. The suggested method was used to determine TIM in dosage forms. No measurable difference was obtained when the result statistically compared with respect to accuracy and precision with reported HPLC method.