Search

In this paper, a kind of soybean nodule-derived nitrogen-doped carbon (SNNDC) was prepared, characterized and applied to modify the assembled carbon paste electrode (CPE), to fabricate a novel chemical sensor for the detections of AA and DA. The electrochemical characteristics of SNNDC implied that it is an effective electron transfer mediator accelerating the electron transfer to CPE. The cyclic voltammetry measurements at different scan rates indicated that the electrochemical process on the electrode surface of the chemical sensor is a diffusion-controlled irreversible oxidation reaction of one-electron and one-proton for DA, and two-electron with one-proton for AA. The linear detection ranges of the chemical sensor for the detections of AA and DA were 5–3000 μM and 5–1000 μM with the detection limits of 1.90 μM and 3.18 μM, respectively, as determined by amperometric experiments. Both linear detection range and detection limit obtained are comparable or better than those of several modified electrodes reported recently. And the chemical sensor was also successfully applied to the detections of AA and DA in injection samples. This study suggested that the fabricated chemical sensor is a hopeful candidate to be used in the detection of pharmaceutical samples of AA and DA, and provides valuable reference information for the development of novel drug sensors in both clinical laboratory and food industries.

Sediment samples in this study were taken from five typical sites near the outlet of Shekou industrial district of Shenzhen City, China. The concentrations of seven elements including Cr, Cu, Cd, Pb, Hg, Zn, and As were determined respectively by atomic absorption spectrometry or atomic fluorescence spectrometry. The pollution degrees of the seven elements were assessed with the contamination factor and potential ecological risk index respectively, and their different sources were identified using multivariate statistical methods. The calculated contamination factors of these elements indicated that the sediments were at least moderately polluted by all the surveyed elements except As. The values of potential ecological risk indexes obtained decreased as the following order: Cd > Hg > Cu > As > Pb > Zn > Cr, and suggested that Cd and Hg were respectively at high and considerable environmental health risks. In addition, multivariate statistical analyses indicated that Cd, Hg, Cu, and Zn were most likely from the waste of electroplating, metal, and battery industries at Shekou industrial district, while Pb and As originated from both natural processes and anthropogenic activities along the bank of Pear River such as coal transportation and combustion, glass manufacturing, and painting, and Cr came mostly from Cr-related industries especially leather tanning within Shenzhen City. This study provided useful reference information about heavy metal contamination in the sediments in the estuarine and coastal areas with rapid urbanization and industrialization, and should be very helpful for the local governments to make relevant policies and strategies of heavy metal contamination control and management in developing countries.

Sediment samples in this study were taken from five typical sites near the outlet of Shekou industrial district of Shenzhen City, China. The concentrations of seven elements including Cr, Cu, Cd, Pb, Hg, Zn, and As were determined respectively by atomic absorption spectrometry or atomic fluorescence spectrometry. The pollution degrees of the seven elements were assessed with the contamination factor and potential ecological risk index respectively, and their different sources were identified using multivariate statistical methods. The calculated contamination factors of these elements indicated that the sediments were at least moderately polluted by all the surveyed elements except As. The values of potential ecological risk indexes obtained decreased as the following order: CdHgCuAsPbZnCr, and suggested that Cd and Hg were respectively at high and considerable environmental health risks. In addition, multivariate statistical analyses indicated that Cd, Hg, Cu, and Zn were most likely from the waste of electroplating, metal, and battery industries at Shekou industrial district, while Pb and As originated from both natural processes and anthropogenic activities along the bank of Pear River such as coal transportation and combustion, glass manufacturing, and painting, and Cr came mostly from Cr-related industries especially leather tanning within Shenzhen City. This study provided useful reference information about heavy metal contamination in the sediments in the estuarine and coastal areas with rapid urbanization and industrialization, and should be very helpful for the local governments to make relevant policies and strategies of heavy metal contamination control and management in developing countries.

Polymannuronate (PM) is an acidic polymer separated from alginate. PM is a linear block polysaccharide in edible brown algae that has been widely used in the food industry. Seleno-polymannuronate (Se-PM) is a seleno-derivative of PM synthesized from PM and Na2SO3 in our laboratory. We investigated the anti-neuroinflammatory activity of Se-PM in lipopolysaccharide (LPS)-activated primary microglia and astrocytes and a mouse model of acute inflammation. Our results show that Se-PM could markedly reduce NO and PGE2 production, iNOS and COX-2 expression, and TNF-α, IL-1β and IL-6 secretion in LPS-treated primary microglia and astrocytes. Moreover, the LPS-triggered overactivation of NF-κB and MAPK signalling was attenuated by Se-PM. In addition, in vivo, LPS-induced microglial and astrocytic activation was remarkably suppressed by Se-PM. These results suggest that Se-PM merits exploration as an alternative medicinal or functional food for alleviating neuroinflammation.

The objective of this longitudinal study was to identify growth curves and related predictors of depressive symptoms among Chinese adolescent earthquake survivors. A total of 1573 adolescent survivors of the 8-magnitude Wenchuan earthquake were assessed through the Depression Self-Rating Scale for Children (cutoff for probable clinical depression: 15), Social Support Rate Scale, Adolescent Self-Rating Life Events Checklist, and a self-designed questionnaire covering earthquake exposure and demographic information at 6-, 12-, 18-, 24- and 30-months after the earthquake. Data were analyzed using growth mixture modeling (GMM) and multinomial logistic regression. The prevalence rates of depressive symptoms were 27.6%, 40.6%, 30.9%, 37.5% and 29.8% at 6-, 12-, 18-, 24- and 30-months, respectively. GMM analysis showed four patterns of growth curves for depressive symptoms: chronic depression (25.6% of the sample), recovery (1.7%), delayed depression (4.3%), and resilience (68.4%). Female gender was related with decreased probability of resilience. Direct witness of tragic scenes during the earthquake was related with higher risk for chronic depression. More negative life events and fewer social support were also common predictors of not developing the resilience pattern. The need of providing appropriate individualized interventions for high-risk adolescent earthquake survivors is indicated., Highlights • About 2/3 of adolescent survivors showed persistent euthymia post-earthquake. • About one quarter of them showed persistent depressive symptomatology. • Others showed a gradual relief or delayed-onset of depressive symptoms over time. • Female sex and directly viewing tragic scenes lowered the probability for euthymia. • Life adversity and less social support also predicted worse outcome than euthymia.

The effect of RCMF-magnetic therapy apparatus on signal substances was studied. The radioimmunoassay (RIA) suggested that the magnetic field increased beta-endorphin markedly in plasma. ELISA indicated that the magnetic field inhibited vomiting reaction induced by chemotherapy drug, with reversible decrease of serotonin (5-HT) level in brains, small intestine tissue and serum. Furthermore, the bioeffect of magnetic fields on 5-HT level presented a typical window effect and post-effect, and the inhibitory effect of magnetic field on the emesis was parallel to the decrease level of 5-HT. This result implied that the decrease of 5-HT might be the basis of rotating constant magnetic field (RCMF) inhibiting drug-induced emesis. The nitric acid reductase-spectrophotometry and nicotinamide adenine dinucleotide-diaphorase/arginine-vasopressin (AVP) cytochemistry technique showed that the magnetic field induced nitric oxide (NO) increase in hypothalamus and the high NO(A) level lasted for 3 hours. The results suggested that NO(A) increases after the treatment of the magnetic field in hypothalamus, which may result from strong expression of NO-ergic neuron in paraventricular hypothalamic nucleus (PVN), periventricular hypothalamic nucleus (PEN) and supraoptic nucleus (SON). The coexistence of NO and AVP may play an important role in the regulation of endocrine and neuroendocrine by the magnetic field. And our data also confirmed that the magnetic field increased the content of NO so strongly that high NO level lasted for 3 hours, also made neuropeptide Y (NPY) cell in medulla stained heavily.