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- Author or Editor: S. Li x
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Summary
An efficient method used to separate five bioactive compounds from Gelidium amansii was optimized by the HCI software. The optimum composition of mobile phase for high-performance liquid chromatographic (HPLC) separation was obtained. The elution profiles were calculated by the polynomial theory based on the retention factor ln k = A + BF + CF 2 (F was the volume percentage of acetonitrile with 1.0% acetic acid); then, the theory was applied to calculate the elution profile in both isocratic and gradient modes by modifying different mobile phase conditions with HCI program. The calculated results of mobile phase condition suggested that acetonitrile-water (containing 1.0% acetic acid) with a linear gradient elution of 0∼30 min from 15:85 to 50:50 (v/v) was the optimized component. In the experimental conditions, the agreement between the experimental elution profiles and the calculated values of eluted concentration was relatively good.
Background and aims
Internet addiction disorder (IAD) is common in university students. A number of studies have examined the prevalence of IAD in Chinese university students, but the results have been inconsistent. This is a meta-analysis of the prevalence of IAD and its associated factors in Chinese university students.
Methods
Both English (PubMed, PsycINFO, and Embase) and Chinese (Wan Fang Database and Chinese National Knowledge Infrastructure) databases were systematically and independently searched from their inception until January 16, 2017.
Results
Altogether 70 studies covering 122,454 university students were included in the meta-analysis. Using the random-effects model, the pooled overall prevalence of IAD was 11.3% (95% CI: 10.1%–12.5%). When using the 8-item Young Diagnostic Questionnaire, the 10-item modified Young Diagnostic Questionnaire, the 20-item Internet Addiction Test, and the 26-item Chen Internet Addiction Scale, the pooled prevalence of IAD was 8.4% (95% CI: 6.7%–10.4%), 9.3% (95% CI: 7.6%–11.4%), 11.2% (95% CI: 8.8%–14.3%), and 14.0% (95% CI: 10.6%–18.4%), respectively. Subgroup analyses revealed that the pooled prevalence of IAD was significantly associated with the measurement instrument (Q = 9.41, p = .024). Male gender, higher grade, and urban abode were also significantly associated with IAD. The prevalence of IAD was also higher in eastern and central of China than in its northern and western regions (10.7% vs. 8.1%, Q = 4.90, p = .027).
Conclusions
IAD is common among Chinese university students. Appropriate strategies for the prevention and treatment of IAD in this population need greater attention.
A rapid and sensitive ultraperformance liquid chromatography-multiple reaction monitoring-multi-stage/mass spectrometry (UPLC-MRM-MS/MS) method has been developed for simultaneous quantification of salvianolic acid B and tanshinone IIA of salvia tropolone tablets in dog plasma. This was achieved by performing quantification using the MRM acquisition with two channels of MRM-MS/MS and MS full scan for more accuracy qualitative results, and the fragmentation transitions of m/z 295→249, 191 for tanshinone IIA and m/z 297→279, 251 for IS in positive mode, m/z 717→519, 321 for salvianolic acid B and m/z 295→267, 239 for IS in negative mode were selected. The UPLC separation was achieved within 3 min in a single UPLC run. Linear calibration curves were obtained over the concentration range of 10 pg/mL−1 ng/mL for tanshinone IIA and 100 pg/mL−1 for salvianolic acid B. Lower limit of quantitation (LLOQ) was 10 pg/mL and 100 pg/mL for tanshinone IIA and salvianolic acid B, respectively. The inter-day and intra-day precision (relative standard deviation, RSD) in all samples were less than 8.21%, and the recoveries were over 85.9% for both tanshinone IIA and salvianolic acid B. The two channels of MRM with MS full scan approach could provide both qualitative and quantitative results without the need for repetitive analyses and resulted in the reduction of further confirmation experiments and analytical time. The pharmacokinetic study of the two active components of salvia tropolone tablets following oral gavage administration of dogs was thus explored with this method.
Abstract
Nattokinase (NK) is effective in the prevention and treatment of cardiovascular disease. Cucumber is rich in nutrients with low sugar content and is safe for consumption. The aim of this study was to construct a therapeutic cucumber that can express NK, which can prevent and alleviate cardiovascular diseases by consumption. Because the Bitter fruit (Bt) gene contributes to bitter taste but has no obvious effect on the growth and development of cucumber, so the NK-producing cucumber was constructed by replacing the Bt gene with NK by using CRISPR/Cas9. The pZHY988-Cas9-sgRNA and pX6-LHA-U6-NK-T-RHA vectors were constructed and transformed into Agrobacterium tumefaciens EHA105, which was transformed into cucumber by floral dip method. The crude extract of NK-producing cucumber had significant thrombolytic activity in vitro. In addition, treatment with the crude extract significantly delayed thrombus tail appearance, and the thrombin time of mice was much longer than that of normal mice. The degrees of coagulation and blood viscosity as well as hemorheological properties improved significantly after crude extract treatment. These findings show that NK-producing cucumber can effectively alleviate thrombosis and improve blood biochemical parameters, providing a new direction for diet therapy against cardiovascular diseases.
An improved ion-pairing reversed-phase high-performance liquid chromatography method coupled with evaporative light scattering detection (HPLC-ELSD) was developed to determine spectinomycin and its related substances in commercial samples. The method was validated in accordance with International Conference on Harmonization (ICH) guidelines. The specificity of the HPLC-ELSD method was similar to that of the European Pharmacopoeia (Ph. Eur.) method, and repeatability and robustness were markedly improved relative to other reported methods due to our empirical evaluation of separation columns. Indeed, it is a more specific assay of spectinomycin than traditional microbiological techniques. The HPLC-ELSD method was used to evaluate the impurity profiles of eight compounds in seven spectinomycin batches from five different companies. Liquid chromatography coupled with electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) was employed to characterize the structures of these compounds. Though the HPLC-ELSD method was not as sensitive as the Ph. Eur. method, its limit of quantitation (LOQ) (0.16%) was lower than the disregard limit (0.3%) described by the Ph. Eur. 7.0. This suggests that the HPLC-ELSD method is appropriate for routine analysis of spectinomycin and its related substances.
Abstract
Background and aims
Problematic online social networking use is prevalent among adolescents, but consensus about the instruments and their optimal cut-off points is lacking. This study derived an optimal cut-off point for the validated Online Social Networking Addiction (OSNA) scale to identify probable OSNA cases among Chinese adolescents.
Methods
A survey recruited 4,951 adolescent online social networking users. Latent profile analysis (LPA) and receiver operating characteristic curve (ROC) analyses were applied to the validated 8-item OSNA scale to determine its optimal cut-off point.
Results
The 3-class model was selected by multiple criteria, and validated in a randomly split-half subsample. Accordingly, participants were categorized into the low risk (36.4%), average risk (50.4%), and high risk (13.2%) groups. The highest risk group was regarded as “cases” and the rest as “non-cases”, serving as the reference standard in ROC analysis, which identified an optimal cut-off point of 23 (sensitivity: 97.2%, specificity: 95.2%). The cut-off point was used to classify participants into positive (probable case: 17:0%) and negative groups according to their OSNA scores. The positive group (probable cases) reported significantly longer duration and higher intensity of online social networking use, and higher prevalence of Internet addiction than the negative group.
Conclusions
The classification strategy and results are potentially useful for future research that measure problematic online social networking use and its impact on health among adolescents. The approach can facilitate research that requires cut-off points of screening tools but gold standards are unavailable.
Background
The reward deficiency syndrome hypothesis posits that genes are responsible for reward dependence and related behaviors. There is evidence that both bulimia and anorexia nervosa, especially in women, have been linked to a lifetime history of substance use disorder (SUD). There are difficulties in accepting food as an addiction similar to drugs; however, increasingly neuroimaging studies favor such an assertion.
Case presentations
We are reporting the evidence of comorbidity of eating disorders with SUD found within these case presentations. We show 50 case reports derived from two independent treatment centers in Florida that suggest the commonality between food and drug addictions. In an attempt to provide data from this cohort, many participants did not adequately respond to our questionnaire.
Discussion
We propose that dopamine agonist therapy may be of common benefit. Failure in the past may reside in too powerful D2 agonist activity leading to D2 receptor downregulation, while the new methodology may cause a reduction of “dopamine resistance” by inducing “dopamine homeostasis.” While this is not a definitive study, it does provide some additional clinical evidence that these two addictions are not mutually exclusive.
Conclusion
Certainly, it is our position that there is an overlap between food- and drug-seeking behavior. We propose that the studies focused on an effort to produce natural activation of dopaminergic reward circuitry as a type of common therapy may certainly be reasonable. Additional research is warranted.
Background and aims
The aim of this study is to estimate the longitudinal associations between online social networking addiction (OSNA) and depression, whether OSNA predicts development of depression, and reversely, whether depression predicts development of OSNA.
Methods
A total of 5,365 students from nine secondary schools in Guangzhou, Southern China were surveyed at baseline in March 2014, and followed up 9 months later. Level of OSNA and depression were measured using the validated OSNA scale and CES-D, respectively. Multilevel logistic regression models were applied to estimate the longitudinal associations between OSNA and depression.
Results
Adolescents who were depressed but free of OSNA at baseline had 1.48 times more likely to develop OSNA at follow-up compared with those non-depressed at baseline [adjusted OR (AOR): 1.48, 95% confidence interval (CI): 1.14–1.93]. In addition, compared with those who were not depressed during the follow-up period, adolescents who were persistently depressed or emerging depressed during the follow-up period had increased risk of developing OSNA at follow-up (AOR: 3.45, 95% CI: 2.51–4.75 for persistent depression; AOR: 4.47, 95% CI: 3.33–5.99 for emerging depression). Reversely, among those without depression at baseline, adolescents who were classified as persistent OSNA or emerging OSNA had higher risk of developing depression compared with those who were no OSNA (AOR: 1.65, 95% CI: 1.01–2.69 for persistent OSNA; AOR: 4.29; 95% CI: 3.17–5.81 for emerging OSNA).
Conclusion
The findings indicate a bidirectional association between OSNA and depression, meaning that addictive online social networking use is accompanied by increased level of depressive symptoms.
