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- Author or Editor: Meng Zhang x
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Late embryonic proteins (LEA) gene family was abundant mainly in higher plant embryos, which could protect the embryos from the damage caused by abiotic stress, especially drought and salt stresses. In the present study, GmLEA2-1 was cloned from soybean leaf tissue treated by 10% polyethylene glycol 6000 (PEG6000). The results of quantitative real-time PCR (qRT-PCR) revealed a variety of expression patterns of GmLEA2-1 in various tissues of soybean (root, stem, leaf, flower, pod, early embryo and late embryo). GmLEA2-1 gene shared a lower sequence similarity with other typical LEA genes of same group from different species, but similar functions. Overexpression of GmLEA2-1 in transgenic Arabidopsis thaliana conferred tolerance to drought and salt stresses. The fresh weight and dry weight of seedling, the primary root length and the lateral root density of transgenic Arabidopsis plants were higher than those of wild type Arabidopsis (WT) under drought and salt stresses. Cis-acting regulatory elements in the GmLEA2-1 promoter were also predicted. These data demonstrate that GmLEA2-1 protein play an important role in improving drought and salt tolerance in plants.
Background and aims
Internet gaming disorder (IGD) was proposed in Diagnostic and Statistical Manual of Mental Disorders of American Psychiatric Association as an area warranting more research attention. High prevalence of excessive Internet game use and related addictions has been reported in China, especially among youth; however, there is a lack of psychometrically and theoretically sound instruments for assessing IGD in the Chinese language.
Methods
This study aimed to examine the psychometric properties of a Chinese version of the Internet Gaming Disorder Test (IGD-20 Test) among Chinese middle school (n = 569; M age = 13.34; 46.2% females) and university students (n = 523; M age = 20.12; 48.4% females) samples in Beijing, China. All participants voluntarily completed an anonymous questionnaire.
Results
Confirmatory factor analysis results showed that the Chinese version of the IGD-20 Test had five factors (i.e., salience-tolerance, mood modification, withdrawal, conflict, and relapse). Measurement invariance was confirmed across the two samples. The test score was positively associated with the modified Young’s Internet Addiction Test for gaming addiction. Concurrent validation was further demonstrated by the IGD-20 Test’s positive correlation with weekly gameplay and depression symptoms. The latent profile analysis showed four different gamer classes (i.e., regular gamers, low-risk engaged gamers, high-risk engaged gamers, and probable disordered gamers), with the estimated prevalence of 2.1% of the last group.
Discussion and conclusion
The IGD-20 Test was applicable to Chinese youth and its Chinese version generally demonstrated good psychometric properties.
Abstract
Nanosized copper particles are widely used in fields of lubricants, polymers/plastic, metallic coating and ink. Recently, we found that copper particles in different sizes can lead to different toxicological effects. To clarify the target organs of copper particles of different sizes, the inductively coupled plasma mass spectroscopy (ICP-MS) was employed to evaluate the distribution of copper in different organs of mice after a single dose oral exposure. The results suggest that the main target organs for copper nanoparticles are kidney, liver and blood. Liver is the main damaged organ.
Abstract
Isoproturon [N'-(p-cumenyl)-N,N-dimethylurea] was synthesized, and the low-temperature heat capacities were measured with a small sample precise automatic adiabatic calorimeter over the temperature range from 78 to 342 K. No thermal anomaly or phase transition was observed in this temperature range. The melting and thermal decomposition behavior of isoproturon was investigated by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). The melting point and decomposition temperature of isoproturon were determined to be 152.4 and 239.0C. The molar melting enthalpy, and entropy of isoproturon, ΔH m and ΔS m, were determined to be 21.33 and 50.13 J K-1 mol-1, respectively. The fundamental thermodynamic functions of isoproturon relative to standard reference temperature, 298.15 K, were derived from the heat capacity data.
Abstract
Recently, it was reported that the toxicity of copper particles increases with the decrease of the particle size on a mass basis. To understand this phenomenon, inductively coupled plasma mass spectrometry (ICP-MS) techniques and in vitro chemical studies were carried out to explore how they produce toxicity in vivo. The results suggest that when the sizes of particles become small and down to a nanoscale, copper becomes extremely reactive in a simulative intracorporeal environment. The nanosized copper particles consume the hydrogen ions in stomach more quickly than micron ones. These processes further convert the copper nanoparticles into cupric ions whose toxicity is very high in vivo.
Mycoplasma pneumoniae (M. pneumoniae) is one of the most important pathogens that cause respiratory tract infection in children and adults. In this study, we describe a rapid and sensitive colorimetric loop mediated isothermal amplification (LAMP) method to detect M. pneumoniae. The specificity and sensitivity of this assay were detected with 21 common respiratory pathogens and 39 M. pneumoniae DNA. The sensitivity of LAMP was 100% among 39 M. pneumoniae isolates and the specificity was 100% among 9 members of other Mycoplasma and 12 common respiratory pathogens. The lowest detectable limit (LDL) of this assay was 102 copies, which detected by a series of standard M. pneumoniae DNA. To evaluate the clinical applicability of the LAMP assay, a total of 80 clinical samples were examined by conventional PCR, real-time PCR and the LAMP assays, respectively. The positive rates were 15.0%, 32.5% and 26.3%, respectively. This colorimetric LAMP assay demonstrated a high level of sensitivity comparable with that of conventional PCR for the detection of M. pneumoniae. It is a valuable method for simple, cost-effective and rapid detection of M. pneumoniae in the rural areas and basic clinical of China.
Summary
A selective and sensitive liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) method was developed and validated for analysis of xanthotoxol (1), xanthotoxin (2), isoimpinellin (3), bergapten (4), oxypeucedanin (5), imperatorin (6), cnidilin (7), and isoimperatorin (8) in rat bile and urine using pimpinellin as an internal standard (IS). An Agilent 1200 liquid chromatography system (Agilent Technologies, USA) equipped with a quaternary pump, an autosampler, and a column compartment was used for all analyses. Chromatographic separations were performed on a Sapphire C18 column (150 mm × 4.6 mm, 5 μm), and the column temperature was maintained at 30°C; the sample injection volume was 10 μL. The specificity, linearity, accuracy, precision, recovery, matrix effect, and several stabilities were validated for all analytes in the rat bile and urine samples. The method was successfully applied in monitoring the concentrations of eight coumarins in rat bile and urine after a single oral administration of Radix Angelicae Dahuricae extract with a dosage of 8.0 mL/kg. In the bile samples, the eight coumarins excreted completely in twenty-four hours. The average percentages of coumarins (1–8) excreted were 0.045%, 0.019%, 0.177%, 0.105%, 0.337%, 0.023%, 0.024%, 0.021%. In the urine samples, the eight coumarins excreted completely in seventy-two hours. The average percentages of coumarins (1–8) excreted were 1.78%, 0.095%, 0.130%, 0.292%, 0.082%, 0.008%, 0.005%, 0.004%. The method is robust and specific and it can successfully complete the requirements of the excretion study of the eight coumarins in Radix Angelicae Dahuricae.
Abstract
Heat capacities of the carbon nanotubes (CNTs) with different sizes have been measured by modulated temperature differential scanning calorimetry (MDSC) and reported for the first time. The results indicated the values of C p increased with shortening length of CNTs when the diameters of CNTs were between 60 and 100 nm. However, the values of C p of CNTs were not affected by their diameter when the lengths of CNTs were 1–2 um, or not affected by the length of CNTs when their diameters were below 10 nm. The thermal stabilities of the CNTs have been studied by TG-DTG-DSC. The results of TG-DTG showed that thermal stabilities of CNTs were enhanced with their diameters increase. With lengths increase, the thermal stabilities of CNTs increased when their diameters were between 60 and 100 nm, but there is a slight decrease when their diameters were less than 60 nm. The further DSC analyses showed both released heat and T onset increased with the increase of CNTs diameters, which confirms the consistency of the results from both TG-DTG and DSC on CNTs thermal stability.
Abstract
Sarecycline is a narrow-spectrum antibiotic for the treatment of acne, which is a chronic inflammatory disease of the hair follicle sebaceous glands. In the study, UPLC-MS/MS was used to establish a rapid and accurate analytical method. The sarecycline was determined with poziotinib as internal standard (IS) in rat plasma. An ACQUITY UPLC HSS T3 column (2.1 × 100 mm, 1.8 μm) could performe chromatographic separation with the mobile phase (methanol: water of 0.1% formic acid) with gradient elution. The ions of target fragment were m/z 488.19→410.14 for sarecycline and m/z 492.06→354.55 for poziotinib, which could quantify the electrospray ionization of positive multiple reaction monitoring (MRM) mode. The linear calibration curve of the concentration range was 1–1,000 ng/mL for sarecycline with a lower limit of quantification (LLOQ) of 1 ng/mL. The mean recovery was between 82.46 and 95.85% for sarecycline and poziotinib in rat plasma. RSD for precision of inter-day and intra-day were between 3.24 and 13.36%, and the accuracy ranged from 105.26 to 109.75%. The developed and validated method was perfectly used in the pharmacokinetic study and bioavailability of sarecycline after intravenous and oral administration in rats.
Abstract
Background and aims
Internet gaming disorder (IGD) has been recognized as a mental illness. Cognitive and emotional illness representations affect coping and health outcomes. Very little is known about such perceptions related to IGD, in both general and diseased populations. This study examined the psychometric properties of the Revised Illness Perception Questionnaire (IPQ-R) for IGD in a general population that included mostly non-cases while a small proportion of the sample was IGD cases.
Methods
An anonymous cross-sectional telephone survey was conducted in a random sample of 1,501 Chinese community-dwelling adults (41.3% male; mean age = 40.42, SD = 16.85) in Macao, China.
Results
The confirmatory factor analysis identified a modified 6-factor model (i.e., timeline cyclical, consequences, personal control, treatment control, illness coherence, and emotional representations) of 26 items that showed satisfactory model fit and internal consistency. Criterion-related validity was supported by the constructs' significant correlations with stigma (positive correlations: timeline cyclical, consequence, emotional representations; negative correlations: illness coherence). Ever-gamers, compared to never-gamers, reported higher mean scores in the subscales of personal control and illness coherence, and lower mean scores in time cyclical, consequence, and emotional representations. Among the sampled gamers, probable IGD cases were more likely than non-IGD cases to perceive IGD as cyclical and involved more negative emotions.
Conclusions
This study shows that the revised 26-item version of IPQ-R is a valid instrument for assessing illness representation regarding IGD in a general population of Chinese adults. It can be used in future research that examines factors of incidence and prevention related to IGD.
