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- Author or Editor: Min Wang x
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Abstract
An improved and rapid method for determination of90Sr via its daughter nuclide,90Y, in aqueous samples from the low-level radioactive wastes by Cerenkov counting was established. This technique is applicable to beta particles maximum energies greater than 0.263 MeV in aqueous solution. A comparison of90Sr determination by Cerenkov counting and standard wet chemical separation techniques indicates a high degree of correlation and excellent agreement. For a 20 ml aqueous sample following the prescribed experimental conditions and a 60 min counting interval, the detection limit was 0.20 dpm/ml (0.10 pCi/ml), and the relative deviation is less then 5%.
Abstract
The aim of this study was to examine the radioiodinating condition of betulinic acid and understand the possibility of 131I–betulinic acid (131I–BA) as a potential tumor radiotherapy agent through in vitro uptake and in vivo biodistribution studies 131I–BA was prepared by the reaction of betulinic acid with Na131I in the presence of hydrogen peroxide, and then purified by HPLC. The labeling yield was about 80%, and the radiochemical purity was greater than 95%. 131I–BA was found to be stable at 4 °C in saline containing 1% ethanol. In vitro studies showed that 131I–betulinic acid accumulated in the cancer cell lines (BEL-7402 and NCI-H446) in comparison with free 131I−. In vivo biodistribution study in KM mice bearing HepA tumor showed that 131I–BA stayed longer time in tumors than free 131I−. A significant differences were seen in tumor/muscle ratio at 4 h postinjection between 131I–BA and free 131I−. In vivo and in vitro studies showed the higher fraction of 131I–BA can be utilized for therapy and a higher dose will be delivered per targeting event. 131I–BA is a promising radiopharmaceutical in nuclear medicine, especially for hepatocellular tumor targeted radionuclide brachytherapy.
Abstract
Background and aims
Individuals with addictive disorders are usually characterized by impaired executive control, persistent craving and excessive reward-seeking. However, it is unclear whether there is a deviation in the connection pattern among the neural systems implicated in these problem behaviors.
Methods
One hundred thirty-six online gaming players were recruited in the current study (68 Internet gaming disorder (IGD) subjects and 68 recreational game users (RGUs) who served as controls matched on age, sex, years of education, and years of gaming). Dynamic interactions among the reward system (striatum), control system (prefrontal cortex), and the interoceptive awareness system (insula) were calculated and compared when subjects were facing gaming cues.
Results
The results revealed that RGUs showed a significant positive correlation in the putamen-middle frontal gyrus (MFG)-insula neural pathway when facing gaming cues, which was missing in the IGD subjects. Additionally, dynamic causal modeling (DCM) analysis revealed that the MFG region was more inhibited by the putamen in the IGD subjects relative to the RGUs.
Conclusions
These findings suggest that the inhibitory neuromodulation of the putamen to the prefrontal cortex in IGD individuals undermines the balance among the tripartite systems. Our findings provide novel neurobiological evidence for understanding the internal connection bias of the addicted individual’s neural system and how the addictive disorder impairs executive control; consequently, the pathway from the striatum to the prefrontal cortex may serve as a potential biomarker to predict the risk of developing an addiction.
Background and aims
Although studies have suggested that individuals with Internet gaming disorder (IGD) may have impairments in cognitive functioning, the nature of the relationship is unclear given that the information is typically derived from cross-sectional studies.
Methods
Individuals with active IGD (n = 154) and those individuals no longer meeting criteria (n = 29) after 1 year were examined longitudinally using functional magnetic resonance imaging during performance of cue-craving tasks. Subjective responses and neural correlates were contrasted at study onset and at 1 year.
Results
Subjects’ craving responses to gaming cues decreased significantly at 1 year relative to study onset. Decreased brain responses in the anterior cingulate cortex (ACC) and lentiform nucleus were observed at 1 year relative to onset. Significant positive correlations were observed between changes in brain activities in the lentiform nucleus and changes in self-reported cravings. Dynamic causal modeling analysis showed increased ACC–lentiform connectivity at 1 year relative to study onset.
Conclusions
After recovery from IGD, individuals appear less sensitive to gaming cues. This recovery may involve increased ACC-related control over lentiform-related motivations in the control over cravings. The extent to which cortical control over subcortical motivations may be targeted in treatments for IGD should be examined further.
Abstract
Laser-induced optical fiber fluorimetry has been first used to analyze uranium(VI) concentration in the kinetic studies on the extraction of uranium(VI) between 0.5 mol/l H3PO4 solution and HDEHP-cyclohexane system with a Lewis cell. The effects of stirring speed, temperature and concentrations of uranium(VI) and HDEHP on the rate of extraction were examined. These data show that the extraction rate of uranium(VI) in this system is controlled by the chemical reaction at the interface. The rate equations and the rate constants of forward and reverse extraction are obtained. The mechanism of the extraction is discussed.
Abstract
Background and aims
Sex differences in internet gaming disorder (IGD) remain unknown. Investigating sex-specific neural features that underlie the core risk factor (i.e., risk-taking) of IGD would help in understanding sex-specific vulnerabilities to IGD and advance sex-specific treatments and prevention for IGD.
Methods
111 participants (28 IGD males, 27 IGD females, 26 recreational game user (RGU) males, 30 RGU females) completed a probability discounting task during fMRI scanning.
Results
First, among RGUs, males showed a higher risk-taking tendency and greater neural activation associated with risk/value evaluation for reward (the ventromedial prefrontal cortex (vmPFC), anterior cingulate cortex (ACC), left putamen) and smaller activation associated with cognitive control (the inferior frontal gyrus) than females during the contrast of risky-safe choices. Moreover, males showed a greater modulatory effect of risky choices on the connection from the vmPFC/ACC to the left putamen than females. Second, IGD males showed decreased activation in the vmPFC/ACC and left putamen compared to RGU males, whereas this decrease did not exist in IGD females.
Discussion
Males show a higher risk-taking tendency than females. Altered neural substrates associated with risky decision-making exist in IGD males but not in IGD females.
Conclusions
The present findings fill the gap in information on the behavioral and neural substrates underlying IGD among females and demonstrate that a high risk-taking tendency is a risk factor and core symptom only in IGD males but not in IGD females. It is necessary to design and adopt distinct treatments and prevention strategies for IGD in males and females.
Abstract
23-Hydroxybetulinic acid (23-HBA) is the efficient antitumor compound extracted from the roots of a Chinese Medicinal Herb, Pulsatilla chinensis (Bge) Regel. To evaluate the effect of radioiodination on cytotoxicity, 23-HBA was radioiodinated with 125I. 125I-23-HBA could be prepared in high yields and good radiochemical purity and was characterized using reverse phase HPLC. In ICR mice bearing Liver Cancer HepA tumor, 125I-23-HBA showed a tumor uptake of 2.1% ID/g at 2 h p.i. and 0.15% ID/g at 48 h p.i on i.v. injection. When injected intratumorally, greater tumor uptake and retention was observed (20% ID/g at 2 h p.i. and 4.6% ID/g at 48 h p.i. respectively).
Abstract
Background
Internet gaming disorder (IGD) is included in the DSM-5 as a provisional diagnosis. Whether IGD should be regarded as a disorder and, if so, how it should be defined and thresholded have generated considerable debate.
Methods
In the current study, machine learning was used, based on regional and interregional brain features. Resting-state data from 374 subjects (including 148 IGD subjects with DSM-5 scores ≥5 and 93 IGD subjects with DSM-5 scores ≥6) were collected, and multivariate pattern analysis (MVPA) was employed to classify IGD from recreational game use (RGU) subjects based on regional brain features (ReHo) and communication between brain regions (functional connectivity; FC). Permutation tests were used to assess classifier performance.
Results
The results demonstrated that when using DSM-5 scores ≥5 as the inclusion criteria for IGD subjects, MVPA could not differentiate IGD subjects from RGU, whether based on ReHo or FC features or by using different templates. MVPA could differentiate IGD subjects from RGU better than expected by chance when using DSM-5 scores ≥6 with both ReHo and FC features. The brain regions involved in the default mode network and executive control network and the cerebellum exhibited high discriminative power during classification.
Discussion
The current findings challenge the current IGD diagnostic criteria thresholding proposed in the DSM-5, suggesting that more stringent criteria may be needed for diagnosing IGD. The findings suggest that brain regions involved in the default mode network and executive control network relate importantly to the core criteria for IGD.
Abstract
In order to evaluate the evolution of contamination we collected river water and sediment samples in the every spring season since 1998. The elemental analysis of water and sediment samples was performed by PIXE using the 3×2 MeV NEC Tandem accelerator at the Taipei Institute of Physics. The characterization of 
- and 
-radioactive levels for water and sediment samples was performed by a BH1216, low background radioactivity instrument at the Shanghai Institute of Nuclear Research. The PIXE results showed that the elemental contents of Cl, K, Ca, Cr, Mn, Fe, Zn and Pb in river water gradually decreased with the rising tide. At high tide, their concentrations were minimum and then increased toward the ebb tide. The analysis also demonstrated that the radioactivity of water samples had been gradually decreasing year by year. It was found that the decreasing rate of -radioactivity was a little quicker than that of -radioactivity. Further aspects of environmental data evaluation and assessment are also discussed.
Abstract
For the disposal of the high efficiency particulate air (HEPA) glass filter to environment, the glass fiber should be leached to lower its radioactive concentration. To derive the optimum method for removal of Co and Cs from HEPA glass fiber, four methods were applied in this study. Results of electrochemical leaching of glass fiber by 4.0 M HNO3–0.1 M Ce(IV) solution showed that the removal efficiency of 134Cs, 137Cs, and 60Cs from glass fiber after 5 h was 96.4, 93.6, and 93.8%, respectively. Results by 5 wt% NaOH solution showed that the removal efficiency of 134Cs, 137Cs, and 60Cs after 30 h was 81.7, 82.1, and 10.0%, respectively. Results by repeat 2.0 M HNO3 solution showed that the removal efficiencies of 134Cs, 137Cs, and 60Cs after 2 h of three repetitions were 96.2, 99.4, and 99.1%, respectively. Finally, results by repeat 4.0 M HNO3 solution showed that the removal efficiencies of 134Cs, 137Cs, and 60Cs after 4 h of three repetitions were 100, 99.9, and 99.9%, respectively, and their radioactivities were below 0.1 Bq/g. Therefore, the chemical leaching method by 4.0 M HNO3 solution was considered as an optimum one for removal of cesium and cobalt from HEPA glass fiber for self disposal. Also the removal efficiencies of 60Co, 134Cs, and 137Cs from the waste-solution after its precipitation-filtration treatment for reuse of 4.0 M HNO3 waste-solution were 88.0, 95.0, and 99.8%.
