Cross-cultural comparison of neurobehavioral performance in Asian workers

Widely-used neurobehavioral tests have been developed and standardized on Western populations, but studies on subject factors for Asian populations have been very limited. For the effective application and interpretation of neurobehavioral tests in Asian populations, an evaluation of the effects of subject factors, including cultural background, is necessary. A cross-cultural study was conducted to evaluate the effects of cultural background and the interaction between cultural background and education on neurobehavioral tests in Asian populations. The Korean version of the Swedish Performance Evaluation System (Simple Reaction Time, Symbol Digit, and Finger Tapping Speed) and a pegboard test were administered to 537 workers who were not exposed to chemicals at work from Fareast (Korea and Chinese), Central (Uzbekistan and Tajikistan), and South Asia (Sri Lanka and Indonesia). The Fareast Asian group exhibited better performance in adjusted test scores than other Asian groups, achieving significance for Symbol Digit and Finger Tapping Speed in both genders. The magnitude of the effect of cultural background on Symbol Digit was comparable to the effect of about 10 years of education. Cultural background did not modify the relation between years of education and Symbol Digit in either males or females. This study may provide the first evidence that cultural background has a large impact on neurobehavioral test performance, even within Asian populations, and suggests that cultural background is a critical confounding factor that must be controlled in epidemiologic studies which include Asian populations in the sample.     

Motor outcome prediction using diffusion tensor tractography in pontine infarct

We investigated whether the integrity of the corticospinal tract classified by diffusion tensor tractography (DTT) can predict the motor outcome in 25 patients with pontine infarct. DTTs were obtained in the early stage of stroke (5-30 days) and were classified into two groups (type A: the integrity of corticospinal tract was preserved around the infarct; type B: corticospinal tract was interrupted). DTT type A patients showed better motor function than the type B patients at 6 months after onset. DTT obtained at the early stage of pontine infarct appears to have predictive value for motor outcome in patients with pontine infarct.     

Anxiety and depression propensities in patients with acute toxic liver injury

AIM:To investigate anxiety and depression propensities in patients with toxic liver injury.METHODS:The subjects were divided into three groups:a healthy control group(Group 1,n=125),an acute non-toxic liver injury group(Group 2,n=124),and a group with acute toxic liver injury group caused by noncommercial herbal preparations(Group 3,n=126).These three groups were compared and evaluated through questionnaire surveys and using the Hospital Anxiety-Depression Scale(HADS),Beck Anxiety Inventory(BAI),Beck Depression Inventory(BDI),and the hypochondriasis scale.RESULTS:The HADS anxiety subscale was 4.9±2.7,5.0±3.0 and 5.6±3.4,in Groups 1,2,and 3,respectively.The HADS depression subscale in Group 3 showed the most significant score(5.2±3.2,6.4±3.4 and 7.2±3.4in Groups 1,2,and 3,respectively)(P<0.01 vs Group 1,P<0.05 vs Group 2).The BAI and BDI in Group 3showed the most significant score(7.0±6.3 and 6.9±6.9,9.5±8.6 and 8.8±7.3,10.7±7.2 and 11.6±8.5in Groups 1,2,and 3,respectively)(BAI:P<0.01 vs Group 1,P<0.05 vs Group 2)(BDI:P<0.01 vs Group1 and 2).Group 3 showed a significantly higher hypochondriasis score(8.2±6.0,11.6±7.5 and 13.1±6.5in Groups 1,2,and 3,respectively)(P<0.01 vs Group 1,P<0.05 vs Group 2).CONCLUSION:Psychological factors that present vulnerability to the temptation to use alternative medicines,such as herbs and plant preparations,are important for understanding toxic liver injury.     

Refined prefrontal working memory network as a neuromarker for Alzheimer’s disease

Detecting Alzheimer’s disease (AD) is an important step in preventing pathological brain damage. Working memory (WM)-related network modulation can be a pathological feature of AD, but is usually modulated by untargeted cognitive processes and individual variance, resulting in the concealment of this key information. Therefore, in this study, we comprehensively investigated a new neuromarker, named “refined network,” in a prefrontal cortex (PFC) that revealed the pathological features of AD. A refined network was acquired by removing unnecessary variance from the WM-related network. By using a functional near-infrared spectroscopy (fNIRS) device, we evaluated the reliability of the refined network, which was identified from the three groups classified by AD progression: healthy people (N=31), mild cognitive impairment (N=11), and patients with AD (N=18). As a result, we identified edges with significant correlations between cognitive functions and groups in the dorsolateral PFC. Moreover, the refined network achieved a significantly correlating metric with neuropsychological test scores, and a remarkable three-class classification accuracy (95.0%). These results implicate the refined PFC WM-related network as a powerful neuromarker for AD screening.     

Enhanced Electron Heat Conduction in TaS3 1D Metal Wire

The 1D wire TaS₃ exhibits metallic behavior at room temperature but changes into a semiconductor below the Peierls transition temperature (T_p), near 210 K. Using the 3ω method, we measured the thermal conductivity κ of TaS₃ as a function of temperature. Electrons dominate the heat conduction of a metal. The Wiedemann–Franz law states that the thermal conductivity κ of a metal is proportional to the electrical conductivity σ with a proportional coefficient of L₀, known as the Lorenz number—that is, κ=σLoT. Our characterization of the thermal conductivity of metallic TaS₃ reveals that, at a given temperature T, the thermal conductivity κ is much higher than the value estimated in the Wiedemann–Franz (W-F) law. The thermal conductivity of metallic TaS₃ was approximately 12 times larger than predicted by W-F law, implying L=12L0. This result implies the possibility of an existing heat conduction path that the Sommerfeld theory cannot account for.     

Which radiograph is most accurate for assessing hip joint penetration in infra-acetabular screw placement?

Although infra-acetabular screws have been used for anterior and posterior column transfixation, a screw penetrating the hip joint can result in harmful complications. However, the most accurate intraoperative radiologic imaging tool for identifying articular penetration has not been established. The purpose of the present study was, therefore, to evaluate the consistency with which standard pelvic radiographs compared with computed tomography (CT) can be used for demonstrating articular penetration.This retrospective review was performed between January 2015 and December 2020. We evaluated the records of patients with acetabular or pelvic fractures who underwent open reduction and internal fixation with infra-acetabular screw placement. We collected demographic data and described infra-acetabular screw placement as follows: ideal placement, articular penetration, and out of the bone. Articular penetration was assessed independently on each pelvic radiograph and compared statistically with the CT scans. Sensitivity, specificity, correct interpretation rate, and prevalence-adjusted bias-adjusted kappa (PABAK) were calculated for each radiograph.Thirty-nine patients underwent infra-acetabular screw placement. The mean age of patients was 55 years (range, 27–90 years); there were 29 men and 10 women. One patient underwent bilateral infra-acetabular screw placement; therefore, 40 infra-acetabular screws were included in total. Six (6/40, 15%) infra-acetabular screws showed articular penetration on CT and two (2/40, 5%) showed infra-acetabular screws extending out of the bone. Hip joint penetration was correctly identified at a rate of 92.5% (95% confidence interval [CI], 79.6–98.4%) on the outlet view and 87.5% (95% CI, 73.2–95.8%) on the anteroposterior (AP) view. The PABAK for the agreement between pelvic radiographs and CT scans was 0.85 in the outlet view and 0.75 in the AP view.The outlet view is an accurate method for detecting articular penetration of infra-acetabular screws. We recommend the insertion of an infra-acetabular screw under fluoroscopic outlet view to avoid articular penetration intraoperatively.     

Pallidal index on MRI as a target organ dose of manganese: structural equation model analysis

We have used a structural equation model (SEM) to analyze the interrelationships among exposure markers, magnetic resonance imaging (MRI) signal index, and neurobehavioral effects. Based on exposure groups, we assessed blood manganese, MRI measurements of pallidal index (PI), and neurobehavioral core test battery (WHO-NCTB) on 111 male workers occupationally exposed to manganese, including welders, smelter workers, and welding rod manufacturing workers. Latent variables were constructed to represent the neurobehavioral effects in an integrated way. The structural equation model revealed that airborne manganese and blood manganese contribute to PI significantly. Manganese exposure in the ambient air may lead to an increase in the internal dose, not only indirectly, by increasing blood manganese level, but also directly, independent of blood concentration. PI significantly contributed to a decrease in neurobehavioral test scores. We found that airborne manganese contributed to PI, and that PI is the most effective predictor of neurobehavioral performance, after adjusting for age and level of education. In conclusion, PI on MRI reflects target organ dose of occupational manganese exposure.