Uncovering the semantics of concepts using GPT-4.

The ability of recent Large Language Models (LLMs) such as GPT-3.5 and GPT-4 to generate human-like texts suggests that social scientists could use these LLMs to construct measures of semantic similarity that match human judgment. In this article, we provide an empirical test of this intuition. We use GPT-4 to construct a measure of typicality-the similarity of a text document to a concept. We evaluate its performance against other model-based typicality measures in terms of the correlation with human typicality ratings. We conduct this comparative analysis in two domains: the typicality of books in literary genres (using an existing dataset of book descriptions) and the typicality of tweets authored by US Congress members in the Democratic and Republican parties (using a novel dataset). The typicality measure produced with GPT-4 meets or exceeds the performance of the previous state-of-the art typicality measure we introduced in a recent paper [G. Le Mens, B. Kovács, M. T. Hannan, G. Pros Rius, Sociol. Sci. 2023, 82-117 (2023)]. It accomplishes this without any training with the research data (it is zero-shot learning). This is a breakthrough because the previous state-of-the-art measure required fine-tuning an LLM on hundreds of thousands of text documents to achieve its performance.

No evidence for the superiority of 3 T MRI over 1.5 T MRI for diagnosing wrist ligamentous lesions: a systematic review and meta-analysis.

PURPOSES: Our aim was to determine the diagnostic accuracy of native MRI regarding different ligamentous lesions of the wrist and to analyze the influence of technical characteristics, such as field strength, application of fat saturation, 3D sequences, and wrist coils. METHODS: The systematic search was performed using MEDLINE, Embase, and CENTRAL databases. Studies that were published before the 12th of February 2024 were included. All studies comparing the diagnostic accuracy of native wrist MRI to that of wrist arthroscopy for suspected ligamentous lesions were included. Results were analyzed by anatomic localization and technical aspects of the MRI. To assess the quality of included studies, we used the revised QUADAS-2 tool. RESULTS: The systematic search revealed 5,181 articles. Thirty-seven studies, reporting 3893 ligamentous lesions, were eligible for inclusion. The studies displayed heterogeneity in terms of technical conditions, such as field strength, the use of wrist coils, the application of 3D sequences and fat saturation. Research methods also varied. Overall sensitivity and specificity were 0.78 (0.66 - 0.86) and 0.81 (0.70 - 0.89) for 1.5T MRI, while sensitivity was 0.73 (0.68 - 0.78) and specificity was 0.90 (0.59 - 0.98) for 3T MRI. There was no significant difference between the two subgroups (p=0,3807 and p=0,4248). Sensitivity was 0.82 (0.75 - 0.87) for triangular fibrocartilage complex (TFCC) lesions, 0.63 (0.50 - 0.74) for scapholunate ligament (SL) tears, and 0.41 (0.25 - 0.60) for lunotriquetral ligament (LT) lesions. Specificity for TFCC lesions was 0.82 (0.73 - 0.89), for SL tears 0.86 (0.73 - 0.93), and for LT lesions 0.93 (0.81 - 0.98). CONCLUSION: The sensitivity and specificity of MRI is influenced by the anatomic location of the lesion and technical conditions. In terms of diagnostic accuracy, no significant difference was found between 1.5T and 3T MRI. LEVEL OF EVIDENCE: III. Systematic review of Level II. - III.

Severity of rotator cuff disorders and additional load affect fluoroscopy-based shoulder kinematics during arm abduction.

BACKGROUND: Rotator cuff disorders, whether symptomatic or asymptomatic, may result in abnormal shoulder kinematics (scapular rotation and glenohumeral translation). This study aimed to investigate the effect of rotator cuff tears on in vivo shoulder kinematics during a 30° loaded abduction test using single-plane fluoroscopy. MATERIALS AND METHODS: In total, 25 younger controls, 25 older controls and 25 patients with unilateral symptomatic rotator cuff tears participated in this study. Both shoulders of each participant were analysed and grouped on the basis of magnetic resonance imaging into healthy, rotator cuff tendinopathy, asymptomatic and symptomatic rotator cuff tears. All participants performed a bilateral 30° arm abduction and adduction movement in the scapular plane with handheld weights (0, 2 and 4 kg) during fluoroscopy acquisition. The range of upward-downward scapular rotation and superior-inferior glenohumeral translation were measured and analysed during abduction and adduction using a linear mixed model (loads, shoulder types) with random effects (shoulder ID). RESULTS: Scapular rotation was greater in shoulders with rotator cuff tendinopathy and asymptomatic rotator cuff tears than in healthy shoulders. Additional load increased upward during abduction and downward during adduction scapular rotation (P < 0.001 in all groups but rotator cuff tendinopathy). In healthy shoulders, upward scapular rotation during 30° abduction increased from 2.3° with 0-kg load to 4.1° with 4-kg load and on shoulders with symptomatic rotator cuff tears from 3.6° with 0-kg load to 6.5° with 4-kg load. Glenohumeral translation was influenced by the handheld weights only in shoulders with rotator cuff tendinopathy (P ≤ 0.020). Overall, superior glenohumeral translation during 30° abduction was approximately 1.0 mm with all loads. CONCLUSIONS: The results of glenohumeral translation comparable to control but greater scapular rotations during 30° abduction in the scapular plane in rotator cuff tears indicate that the scapula compensates for rotator cuff deficiency by rotating. Further analysis of load-dependent joint stability is needed to better understand glenohumeral and scapula motion. LEVEL OF EVIDENCE: Level 2. TRIAL REGISTRATION: Ethical approval was obtained from the regional ethics committee (Ethics Committee Northwest Switzerland EKNZ 2021-00182), and the study was registered at clinicaltrials.gov on 29 March 2021 (trial registration number NCT04819724, https://clinicaltrials.gov/ct2/show/NCT04819724 ).

Chronic stage magnetic resonance imaging findings in patients with shoulder injury related to vaccine administration (SIRVA).

PURPOSE: Identify chronic shoulder MRI findings in patients with known shoulder injury related to vaccine administration (SIRVA). MATERIALS AND METHODS: Two fellowship-trained musculoskeletal radiologists retrospectively reviewed the MRI of nine patients with clinically established SIRVA. MRI was performed at least 4 weeks after vaccination and included intravenous contrast-enhanced sequences. MRI was reviewed for the presence of erosions, tendonitis, capsulitis, synovitis, bone marrow oedema, joint effusion, bursitis, cartilage defects, rotator cuff lesions, and lymphadenopathy. The number and location of focal lesions were recorded. RESULTS: Erosions of the greater tuberosity were present in 8/9 (89%), tendonitis of the infraspinatus muscle tendon in 7/9 (78%), capsulitis, synovitis, and bone marrow oedema in 5/9 (56%) cases, respectively. Effusion was found in three, and subdeltoid bursitis, rotator cuff lesions as well as cartilage defects in one patient, respectively. None of our included subjects showed axillary lymphadenopathy. CONCLUSION: In this case series, greater humeral tuberosity erosions, infraspinatus muscle tendonitis, capsulitis, synovitis, and bone marrow oedema were common MRI findings in chronic SIRVA.

Load-induced increase in muscle activity during 30° abduction in patients with rotator cuff tears and control subjects.

BACKGROUND: Rotator cuff muscles stabilise the glenohumeral joint and contribute to the initial abduction phase with other shoulder muscles. This study aimed to determine if the load-induced increase in shoulder muscle activity during a 30° abduction test is influenced by asymptomatic or symptomatic rotator cuff pathologies. MATERIALS AND METHODS: Twenty-five patients with unilateral rotator cuff tears (age, 64.3 ± 10.2 years), 25 older control subjects (55.4 ± 8.2 years) and 25 younger control subjects (26.1 ± 2.3 years) participated in this study. Participants performed a bilateral 30° arm abduction and adduction movement in the scapular plane with handheld weights (0-4 kg). Activity of the deltoid, infraspinatus, biceps brachii, pectoralis major, latissimus dorsi and upper trapezius muscles was analysed at maximum abduction angle after normalisation to maximum voluntary contraction. Shoulders were classified into rotator cuff tendinopathy, asymptomatic and symptomatic rotator cuff tears, and healthy based on magnetic resonance images. A linear mixed model (loads, shoulder types) with random effects (shoulder identification) was applied to the log-transformed muscle activities. RESULTS: Muscle activity increased with increasing load in all muscles and shoulder types (P < 0.001), and 1-kg increments in additional weights were significant (P < 0.001). Significant effects of rotator cuff pathologies were found for all muscles analysed (P < 0.05). In all muscles, activity was at least 20% higher in symptomatic rotator cuff tears than in healthy shoulders (P < 0.001). Symptomatic rotator cuff tears showed 20-32% higher posterior deltoid (P < 0.05) and 19-25% higher pectoralis major (P < 0.01) activity when compared with asymptomatic tears. CONCLUSIONS: Rotator cuff pathologies are associated with greater relative activity of shoulder muscles, even with low levels of additional load. Therefore, the inclusion of loaded shoulder tests in the diagnosis and rehabilitation of rotator cuff pathologies can provide important insight into the functional status of shoulders and can be used to guide treatment decisions. LEVEL OF EVIDENCE: Level 2. TRIAL REGISTRATION: Ethical approval was obtained from the regional ethics committee (Ethics Committee Northwest Switzerland EKNZ 2021-00182), and the study was registered at clinicaltrials.gov on 29 March 2021 (trial registration number NCT04819724, https://clinicaltrials.gov/ct2/show/NCT04819724 ).

Diagnostics of infrapatellar saphenous neuralgia-a reversible cause of chronic anteromedial pain following knee surgery.

OBJECTIVES: To evaluate the impact of diagnostic nerve block and ultrasound findings on therapeutic choices and predict the outcome after concomitant surgery in patients with suspected neuropathy of the infrapatellar branch of the saphenous nerve (IPBSN). METHODS: Fifty-five patients following knee surgery with suspicion of IPBSN neuralgia were retrospectively included. Ultrasound reports were assessed for neuroma and postsurgical scarring (yes/no). Responders and non-responders were assigned following anesthetic injection of the IPBSN. The type of procedure (neurectomy/interventional pain procedure/other than nerve-associated therapy) and pain score at initial follow-up were recorded and patients were assigned as positive (full pain relief) or negative (partial/no pain relief) to therapeutic nerve treatment. Factors associated with a relevant visual analog scale (VAS) reduction were assessed using uni- and multivariate logistic regression models and chi-square for quantitative and qualitative variables (p ≤ 0.05). RESULTS: Responders (37/55) more often had an entrapment or an evident neuroma of the IPBSN (97% vs. 6%). A positive Hoffmann-Tinel sign (p = 0.002) and the absence of knee joint instability (p = 0.029) predicted a positive response of the diagnostic nerve block (90%; 26/29). In the follow-up after therapeutic nerve treatment, all patients with full pain relief showed neuromas or entrapment of the IPBSN. Patients negatively responding to therapeutic nerve treatment more frequently showed an additional knee joint instability (25% vs. 4%). CONCLUSION: Selective denervation for neuropathic knee pain is beneficial in selected patients with significant VAS reduction after diagnostic nerve block. Non-responders following diagnostic nerve block but sonographic evidence of IPBSN pathologies need to be evaluated for other causes such as knee joint instability. KEY POINTS: • Sonographic diagnosis of neuroma or entrapment of the IPBSN is frequently seen in patients with anteromedial knee pain and leads to a good response to diagnostic nerve block following knee surgery. • The vast majority of patients with clinical signs of IPBSN neuropathy and response to a diagnostic nerve block sustained full pain relief following therapeutic nerve treatment. • Patients not responding to therapeutic IPBSN treatment have to be evaluated for other causes of anteromedial knee pain such as knee joint instability.

Microaerobic enrichment of benzene-degrading bacteria and description of Ideonella benzenivorans sp. nov., capable of degrading benzene, toluene and ethylbenzene under microaerobic conditions.

In the present study, the bacterial community structure of enrichment cultures degrading benzene under microaerobic conditions was investigated through culturing and 16S rRNA gene Illumina amplicon sequencing. Enrichments were dominated by members of the genus Rhodoferax followed by Pseudomonas and Acidovorax. Additionally, a pale amber-coloured, motile, Gram-stain-negative bacterium, designated B7T was isolated from the microaerobic benzene-degrading enrichment cultures and characterized using a polyphasic approach to determine its taxonomic position. The 16S rRNA gene and whole genome-based phylogenetic analyses revealed that strain B7T formed a lineage within the family Comamonadaceae, clustered as a member of the genus Ideonella and most closely related to Ideonella dechloratans CCUG 30977T. The sole respiratory quinone is ubiquinone-8. The major fatty acids are C16:0 and summed feature 3 (C16:1 ω7c/iso-C15:0 2-OH). The DNA G + C content of the type strain is 68.8 mol%. The orthologous average nucleotide identity (OrthoANI) and in silico DNA-DNA hybridization (dDDH) relatedness values between strain B7T and closest relatives were below the threshold values for species demarcation. The genome of strain B7T, which is approximately 4.5 Mb, contains a phenol degradation gene cluster, encoding a multicomponent phenol hydroxylase (mPH) together with a complete meta-cleavage pathway including a I.2.C-type catechol 2,3-dioxygenase (C23O) gene. As predicted by the genome, the type strain is involved in aromatic hydrocarbon-degradation: benzene, toluene and ethylbenzene are degraded aerobically and also microaerobically as sole source of carbon and energy. Based on phenotypic characteristics and phylogenetic analysis, strain B7T is a member of the genus Ideonella and represents a novel species for which the name Ideonella benzenivorans sp. nov. is proposed. The type strain of the species is strain B7T (= LMG 32,345T = NCAIM B.02664T).

Antiproliferative and cytotoxic effects of sesquiterpene lactones isolated from Ambrosia artemisiifolia on human adenocarcinoma and normal cell lines.

CONTEXT: Ambrosia artemisiifolia L. (Asteraceae) contains sesquiterpene lactones as characteristic secondary metabolites. Many of these compounds exert antiproliferative and cytotoxic effects. OBJECTIVE: To isolate the sesquiterpene lactones from the aerial part of A. artemisiifolia and to elucidate their cytotoxic, antiproliferative and antibacterial effects. MATERIALS AND METHODS: The compounds were identified by one-dimensional (1D) and 2D NMR, HR-MS spectroscopy from the methanol extract. Isolated compounds were investigated for their cytotoxic and antiproliferative effects on human colonic adenocarcinoma cell lines and human embryonal lung fibroblast cell line using MTT assay. The selectivity of the sesquiterpenes was calculated towards the normal cell line. To check the effect of drug interactions between compounds and doxorubicin, multidrug-resistant Colo 320 cells were used. RESULTS: A new seco-psilostachyinolide derivative, 1,10-dihydro-1'-noraltamisin, and seven known compounds were isolated from the methanol extract. Acetoxydihydrodamsin had the most potent cytotoxic effect on sensitive (Colo205) cell line (IC50 = 7.64 µM), also the strongest antiproliferative effect on Colo205 (IC50 = 5.14 µM) and Colo320 (IC50 = 3.67 µM) cell lines. 1'-Noraltamisin (IC50 = 8.78 µM) and psilostachyin (IC50 = 5.29 µM) showed significant antiproliferative effects on the multidrug-resistant Colo320 cell line and had moderate selectivity against human embryonal lung fibroblast cell line. Psilostachyin C exhibited cytotoxic effects on Colo205 cells (IC50 = 26.60 µM). None of the isolated compounds inhibited ABCB1 efflux pump (EP; P-glycoprotein) or the bacterial EPs. DISCUSSION AND CONCLUSIONS: Acetoxydihydrodamsin, 1'-noraltamisin, and psilostachyin showed the most remarkable cytotoxic and antiproliferative activity on tumour cell lines and exerted selectivity towards MRC-5 cell line.

AI-based detection and classification of distal radius fractures using low-effort data labeling: evaluation of applicability and effect of training set size.

OBJECTIVES: To evaluate the performance of a deep convolutional neural network (DCNN) in detecting and classifying distal radius fractures, metal, and cast on radiographs using labels based on radiology reports. The secondary aim was to evaluate the effect of the training set size on the algorithm's performance. METHODS: A total of 15,775 frontal and lateral radiographs, corresponding radiology reports, and a ResNet18 DCNN were used. Fracture detection and classification models were developed per view and merged. Incrementally sized subsets served to evaluate effects of the training set size. Two musculoskeletal radiologists set the standard of reference on radiographs (test set A). A subset (B) was rated by three radiology residents. For a per-study-based comparison with the radiology residents, the results of the best models were merged. Statistics used were ROC and AUC, Youden's J statistic (J), and Spearman's correlation coefficient (ρ). RESULTS: The models' AUC/J on (A) for metal and cast were 0.99/0.98 and 1.0/1.0. The models' and residents' AUC/J on (B) were similar on fracture (0.98/0.91; 0.98/0.92) and multiple fragments (0.85/0.58; 0.91/0.70). Training set size and AUC correlated on metal (ρ = 0.740), cast (ρ = 0.722), fracture (frontal ρ = 0.947, lateral ρ = 0.946), multiple fragments (frontal ρ = 0.856), and fragment displacement (frontal ρ = 0.595). CONCLUSIONS: The models trained on a DCNN with report-based labels to detect distal radius fractures on radiographs are suitable to aid as a secondary reading tool; models for fracture classification are not ready for clinical use. Bigger training sets lead to better models in all categories except joint affection. KEY POINTS: • Detection of metal and cast on radiographs is excellent using AI and labels extracted from radiology reports. • Automatic detection of distal radius fractures on radiographs is feasible and the performance approximates radiology residents. • Automatic classification of the type of distal radius fracture varies in accuracy and is inferior for joint involvement and fragment displacement.

In vivo 3D tomography of the lumbar spine using a twin robotic X-ray system: quantitative and qualitative evaluation of the lumbar neural foramina in supine and upright position.

OBJECTIVES: Supine lumbar spine examinations underestimate body weight effects on neuroforaminal size. Therefore, our purpose was to evaluate size changes of the lumbar neuroforamina using supine and upright 3D tomography and to initially assess image quality compared with computed tomography (CT). METHODS: The lumbar spines were prospectively scanned in 48 patients in upright (3D tomographic twin robotic X-ray) and supine (30 with 3D tomography, 18 with CT) position. Cross-sectional area (CSA), cranio-caudal (CC), and ventro-dorsal (VD) diameters of foramina were measured by two readers and additionally graded in relation to the intervertebral disc height. Visibility of bone/soft tissue structures and image quality were assessed independently on a 5-point Likert scale for the 18 patients scanned with both modalities. Descriptive statistics, Wilcoxon's signed-rank test (p < 0.05), and interreader reliability were calculated. RESULTS: Neuroforaminal size significantly decreased at all levels for both readers from the supine (normal intervertebral disc height; CSA 1.25 ± 0.32 cm2; CC 1.84 ± 0.24 cm2; VD 0.88 ± 0.16 cm2) to upright position (CSA 1.12 ± 0.34 cm2; CC 1.78 ± 0.24 cm2; VD 0.83 ± 0.16 cm2; each p < 0.001). Decrease in intervertebral disc height correlated with decrease in foraminal size (supine: CSA 0.88 ± 0.34 cm2; CC 1.39 ± 0.33 cm2; VD 0.87 ± 0.26 cm2; upright: CSA 0.83 ± 0.37 cm2, p = 0.010; CC 1.32 ± 0.33 cm2, p = 0.015; VD 0.80 ± 0.21 cm2, p = 0.021). Interreader reliability for area was fair to excellent (0.51-0.89) with a wide range for cranio-caudal (0.32-0.74) and ventro-dorsal (0.03-0.70) distances. Image quality was superior for CT compared with that for 3D tomography (p < 0.001; κ, CT = 0.66-0.92/3D tomography = 0.51-1.00). CONCLUSIONS: The size of the lumbar foramina is smaller in the upright weight-bearing position compared with that in the supine position. Image quality, especially nerve root delineation, is inferior using 3D tomography compared to CT. KEY POINTS: • Weight-bearing examination demonstrates a decrease of the neuroforaminal size. • Patients with higher decrease in intervertebral disc showed a narrower foraminal size. • Image quality is superior with CT compared to 3D tomographic twin robotic X-ray at the lumbar spine.

MR variability of collagen meniscal implant remodelling in patients with good clinical outcome.

PURPOSE: Collagen meniscal implants (CMI) have variable imaging findings on MRI and it remains ambiguous, if alterations may be present in asymptomatic patients. The aim was, to evaluate MR morphological characteristics and volume of CMI in the early, mid- and long-term follow-up. METHODS: Fifty-seven patients (mean age, 43.6±11 years; 41 male/16 female) with good clinical outcome (subjective visual analogue scale for satisfaction < 2 and a Lysholm-score ≥ 84) after CMI were assessed retrospectively using MRI 1, 2 and 3-8 years postoperatively. CMI morphology, signal intensity (SI), homogeneity and size were assessed and a meniscal score was calculated. Chondral defects and bone marrow edema pattern were reported and summarized in a chondral score. Meniscal extrusion and volume were evaluated. Intra- and inter-reader reliabilities were calculated. Spearman and partial correlations were used (p < 0.05). RESULTS: One year postoperatively, the CMI varied in size [10% (4/40) normal, 30% (12/40) small, 60% (24/40) hypertrophic] and was hyperintense and inhomogeneous in all patients. At long-term follow-up, the size of CMI decreased [6% (1/17) resorbed, 18% (3/17) normal, 41% (7/17) small, 35% (6/17) hypertrophic]. The SI of the CMI changed to normal in only 13% (2/16). The majority was still hyperintense [87% (14/16)]. Less meniscal extrusion was present in the follow-up [71% (11/16) versus initially 93% (37/40)]. The meniscal score improved significantly (ρ = 0.28). Over time, full-thickness femoral chondral defects were increasingly present [65% (10/17) versus initially 33% (13/40)] and the chondral score worsened significantly (p = 0.017). CONCLUSION: Abnormal and inhomogeneous SI and irregular margins of the early postoperative CMI on MRI are findings seen in patients with good clinical results and should not necessarily be overcalled when reporting MRI. These features tend to decrease over time. LEVEL OF EVIDENCE: IV.

Language-Style Similarity and Social Networks.

This research demonstrates that linguistic similarity predicts network-tie formation and that friends exhibit linguistic convergence over time. In Study 1, we analyzed the linguistic styles and the emerging social network of a complete cohort of 285 students. In Study 2, we analyzed a large-scale data set of online reviews. In both studies, we collected data in two waves to examine changes in both social networks and linguistic styles. Using the Linguistic Inquiry and Word Count (LIWC) framework, we analyzed the text of students' essays and of 1.7 million reviews by 159,651 Yelp reviewers. Consistent with our theory, results showed that similarity in linguistic style corresponded to a higher likelihood of friendship formation and persistence and that friendship ties, in turn, corresponded to a convergence in linguistic style. We discuss the implications of the coevolution of linguistic styles and social networks, which contribute to the formation of relational echo chambers.

Comparison of 3D X-ray tomography with computed tomography in patients with distal extremity fractures.

OBJECTIVE: To compare fracture detection, image quality, and radiation dose in patients with distal extremity fractures using 3D tomography and computed tomography (CT). MATERIALS AND METHODS: IRB approval was obtained including informed consent for this prospective study from June to December 2016. Patients diagnosed with an acute fracture at CT were consecutively scanned on the same day using 3D tomography. Anatomical location (effected bone and location within the bone) and morphological characteristics of fractures (avulsion, articular involvement, mono- vs. multifragmented, displacement), visibility of bone/soft tissue structures, and image quality were assessed independently by two blinded readers on a 5-point Likert scale. Dose-length-product (DLP; mGy*cm) was compared between both modalities. Descriptive statistics, Wilcoxon signed rank test (P < 0.05), Student's t test (P < 0.05), and Cohen's kappa (κ) for interreader reliability were calculated. RESULTS: In 46 patients (28 males; 18 females; mean age, 53 ± 20 years) with 28 hand/wrist and 18 foot/ankle examinations, 86 out of 92 fractures were diagnosed with 3D tomography compared with CT. No false-positive finding occurred at 3D tomography. The six missed fractures on 3D tomography were five avulsion fractures of the carpals/metacarpals or tarsals/metatarsals, respectively, and one nondisplaced fracture of the capitate. Interreader agreement of anatomical location and morphological characteristics was substantial to almost perfect for upper (κ = 0.80-0.96) and lower (κ = 0.70-0.97) extremity fractures. Visibility of bone and soft tissue structures and image quality were slightly inferior using 3D tomography compared with CT (upper extremity P < 0.001-0.038 and lower extremity P < 0.001-0.035). DLP of a comparable scan coverage was significantly lower for 3D tomography (P < 0.001) for both upper (3D mean, 19.4 ± 5.9 mGy*cm; estimated CT mean, 336.5 ± 52.2 mGy*cm) and lower extremities (3D mean, 24.1 ± 11.1 mGy*cm; estimated CT mean, 182.9 ± 6.5 mGy*cm). Even the highest DLP with 3D tomography was < 30% of the mean estimated CT dose of a comparable area of coverage. CONCLUSION: Fracture assessment of peripheral extremities is reliable utilizing a low-dose 3D tomography X-ray system, with slightly reduced image quality.

Testing the Applicability of MALDI-TOF MS as an Alternative Stock Identification Method in a Cryptic Species Complex.

Knowledge of intraspecific variability of a certain species is essential for their long-term survival and for the development of conservation plans. Nowadays, molecular/genetic methods are the most frequently used for this purpose. Although, the Matrix Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS) technique has become a promising alternative tool to specify intraspecific variability, there is a lack of information about the limitations of this method, and some methodological issues need to be resolved. Towards this goal, we tested the sensitivity of this method on an intraspecific level, using genetically identified individuals of a cryptic fish species complex collected from five distinct populations. Additionally, some methodologic issues, such as the effect of (1) delayed sample preparation, (2) clove oil anaesthetization, and (3) different tissue types (muscle, and brain) were investigated using the MS analysis results. Our results show that the delayed sample preparation has a fundamental effect on the result of MS analysis, while at the same time the clove oil did not affect the results considerably. Both the brain and muscle samples were usable for cryptic species identification, but in our opinion this method has limited applicability for population-level segregation. The application of MALDI-TOF MS to the exploitable toolkit of phylogenetic and taxonomic researches could be used to broaden conclusions.

Expression of GLP-1 receptors in insulin-containing interneurons of rat cerebral cortex.

AIMS/HYPOTHESIS: Glucagon-like peptide 1 (GLP-1) receptors are expressed by pancreatic beta cells and GLP-1 receptor signalling promotes insulin secretion. GLP-1 receptor agonists have neural effects and are therapeutically promising for mild cognitive impairment and Alzheimer's disease. Our previous results showed that insulin is released by neurogliaform neurons in the cerebral cortex, but the expression of GLP-1 receptors on insulin-producing neocortical neurons has not been tested. In this study, we aimed to determine whether GLP-1 receptors are present in insulin-containing neurons. METHODS: We harvested the cytoplasm of electrophysiologically and anatomically identified neurogliaform interneurons during patch-clamp recordings performed in slices of rat neocortex. Using single-cell digital PCR, we determined copy numbers of Glp1r mRNA and other key genes in neurogliaform cells harvested in conditions corresponding to hypoglycaemia (0.5 mmol/l glucose) and hyperglycaemia (10 mmol/l glucose). In addition, we performed whole-cell patch-clamp recordings on neurogliaform cells to test the effects of GLP-1 receptor agonists for functional validation of single-cell digital PCR results. RESULTS: Single-cell digital PCR revealed GLP-1 receptor expression in neurogliaform cells and showed that copy numbers of mRNA of the Glp1r gene in hyperglycaemia exceeded those in hypoglycaemia by 9.6 times (p < 0.008). Moreover, single-cell digital PCR confirmed co-expression of Glp1r and Ins2 mRNA in neurogliaform cells. Functional expression of GLP-1 receptors was confirmed with whole-cell patch-clamp electrophysiology, showing a reversible effect of GLP-1 on neurogliaform cells. This effect was prevented by pre-treatment with the GLP-1 receptor-specific antagonist exendin-3(9-39) and was absent in hypoglycaemia. In addition, single-cell digital PCR of neurogliaform cells revealed that the expression of transcription factors (Pdx1, Isl1, Mafb) are important in beta cell development. CONCLUSIONS/INTERPRETATION: Our results provide evidence for the functional expression of GLP-1 receptors in neurons known to release insulin in the cerebral cortex. Hyperglycaemia increases the expression of GLP-1 receptors in neurogliaform cells, suggesting that endogenous incretins and therapeutic GLP-1 receptor agonists might have effects on these neurons, similar to those in pancreatic beta cells.

Development and characterization of 49 novel microsatellite markers in the African catfish, Clarias gariepinus (Burchell, 1822).

The African catfish or sharp tooth catfish (Clarias gariepinus) is one of the important species (due to its high environmental tolerance and easily controllable breeding habits) that can significantly contribute to reducing hunger in many countries. It is farmed in numerous African, Asian, and European countries. Moreover, during the last decades its production has grown significantly worldwide. Currently, following the carp, this species is produced in the second largest volume in Hungary. Despite its economic importance, the stocks have been maintained without genetic control or guided breeding. Molecular genetic data on bred populations or strains are very limited. In order to investigate the genetic structure of the stocks, 49 new microsatellite markers were characterized and tested on 32 individuals from a Hungarian farmed stock. All these markers were polymorph. The number of alleles per locus ranged from 2 to 11. The observed and expected overall heterozygosities were between 0.519 and 0.544 respectively and the overall inbreeding coefficient (Fis: 0.063) does not reveal the presence of inbreeding. However, 63% of the markers showed significant deviations from HWE. The results suggest that the maintenance of genetic variation within the stock require high attention in closed bred populations. These new markers provide a useful tool for population and conservation genetics of natural and bred African catfish populations.

How Endogenous Crowd Formation Undermines the Wisdom of the Crowd in Online Ratings.

People frequently consult average ratings on online recommendation platforms before making consumption decisions. Research on the wisdom-of-the-crowd phenomenon suggests that average ratings provide unbiased quality estimates. Yet we argue that the process by which average ratings are updated creates a systematic bias. In analyses of more than 80 million online ratings, we found that items with high average ratings tend to attract more additional ratings than items with low average ratings. We call this asymmetry in how average ratings are updated endogenous crowd formation. Using computer simulations, we showed that it implies the emergence of a negative bias in average ratings. This bias affects items with few ratings particularly strongly, which leads to ranking mistakes. The average-rating rankings of items with few ratings are worse than their quality rankings. We found evidence for the predicted pattern of biases in an experiment and in analyses of large online-rating data sets.

Short-term effects of T-2 toxin or deoxynivalenol on glutathione status and expression of its regulatory genes in chicken.

Short-term (48-hour) effects of 3.74/1.26 mg kg-1 T-2/HT-2 toxin or 16.12 mg kg-1 DON in feed were investigated in the liver of three-week-old cockerels (body weight: 749.60 ± 90.98 g). Markers of lipid peroxidation showed no significant changes. At hour 24, glutathione content in the T-2/HT-2 toxin group was significantly higher than in the control. Glutathione peroxidase activity was significantly higher than the control at hour 24 in the T-2/H-2 toxin group and at hour 48 in the DON group. In the DON group, expression of the glutathione peroxidase 4 gene (GPX4) was significantly lower than in the control at hours 12 and 14, and higher at hour 48. Expression of the glutathione reductase gene (GSR) was significantly lower than in the control at hour 12 in the T-2/HT-2 toxin group, and at hours 12, 24 and 48 in the DON group. However, at hour 36 higher GSR expression was measured in the DON group. Due to the effect of both trichothecenes, expression of the glutathione synthetase gene (GSS) was significantly lower than in the control at hours 24 and 48. In conclusion, T-2/HT-2 toxin and DON had a moderate short-term effect on free radical formation. T-2/HT-2 toxin induced more pronounced activation of the glutathione redox system than did DON.

Feasibility of Dose Optimization in a Second-Generation Dual-Source CT Scanner for a Manufacturer-Recommended Urolithiasis Protocol for Imaging Renal Stones.

OBJECTIVE: The purpose of this article is to investigate the magnitude of dose optimization for a manufacturer-recommended urolithiasis protocol in a second-generation dual-source CT scanner. MATERIALS AND METHODS: Custom renal phantoms with 24 stones were scanned using the manufacturer-provided dual-energy CT protocol (tube A, 100 kVp and 210 reference mAs; tube B, 140 kVp and 162 reference mAs) and seven dose-optimized protocols in which the reference tube current-time product setting of tube A was reduced stepwise by 20 mAs. Detection and characterization of the stones was assessed. In the patient study, 25 patients underwent the manufacturer-provided dual-energy protocol and 25 patients underwent imaging with a dose-optimized protocol (tube A, 100 kVp and 90 reference mAs; tube B, 140 kVp and 70 reference mAs). Dose-length product (DLP), image noise, and contrast-to-noise ratio (CNR) were assessed. Subjective image quality was analyzed by three independent radiologists. RESULTS: In the phantom study, the reference tube current-time product of tube A could be reduced from 210 to 90 mAs without losing the accuracy of detection or characterization of the calculi. In the patient study, the dose-optimized protocol resulted in a significant reduction of the average DLP by 51% compared with the standard protocol (219.4 vs 443.5 mGy·cm, respectively; p = 0.0001). The image noise was higher, and the CNR was lower, in the dose-optimized group than in the standard-dose group (p < 0.05). The subjective overall image quality of the dose-optimized CT examinations was rated as good, and that of the standard-dose CT examinations was rated as excellent (p = 0.001). CONCLUSION: The in vitro and in vivo assessment revealed a potential for a 51% dose reduction of the manufacturer-recommended dual-energy CT protocol for urolithiasis without compromising the accuracy.

Short-term effects of T-2 toxin or deoxynivalenol on lipid peroxidation and the glutathione system in common carp.

The purpose of this study was to investigate the short-term effects of a single oral dose of T-2 and HT-2 toxin at 0.15, 0.33 and 1.82 mg kg-1 body weight, or deoxynivalenol (DON) and 15-acetyl-DON at 0.13, 0.31 and 1.75 mg kg-1 body weight in common carp. Conjugated dienes and trienes (the early markers of lipid peroxidation) were elevated in all DON-treated groups at the 16th hour, while thiobarbituric acid reactive substances (TBARS; termination marker) were increased at the highest dose of DON at the 16th and 24th hours. T-2 toxin did not cause changes in these parameters. Glutathione content and glutathione peroxidase activity showed higher levels at the 16th hour as the effect of both mycotoxins. The expression of glutathione peroxidase (GPx4) genes (gpx4a and gpx4b) revealed a dual response. Downregulation was observed at the 8th hour, followed by an induction at the 16th hour, at the lowest dose of both mycotoxins. Higher doses revealed long-drawn emergence and an elevation was observed only at the 24th hour. However, at the lowest and highest doses of DON or T-2 toxin the changes in gene expression were delayed, which may be related to the low oxidative stress response, as suggested by the expression profiles of the nrf2, keap1, gpx4a and gpx4b genes.