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Arsenic (As) and fluoride (F) are two of the most common elements contaminating groundwater resources. A growing number of studies have found that As and F can cause neurotoxicity in infants and children, leading to cognitive, learning, and memory impairments. However, early biomarkers of learning and memory impairment induced by As and/or F remain unclear. In the present study, the mechanisms by which As and/or F cause learning memory impairment are explored at the multi-omics level (microbiome and metabolome). We stablished an SD rats model exposed to arsenic and/or fluoride from intrauterine to adult period. Arsenic and/fluoride exposed groups showed reduced neurobehavioral performance and lesions in the hippocampal CA1 region. 16S rRNA gene sequencing revealed that As and/or F exposure significantly altered the composition and diversity of the gut microbiome, featuring the Lachnospiraceae_NK4A136_group, Ruminococcus_1, Prevotellaceae_NK3B31_group, [Eubacterium]_ xylanophilum_group. Metabolome analysis showed that As and/or F-induced learning and memory impairment may be related to tryptophan, lipoic acid, glutamate, gamma-aminobutyric acidergic (GABAergic) synapse, and arachidonic acid (AA) metabolism. The gut microbiota, metabolites, and learning memory indicators were significantly correlated. Learning memory impairment triggered by As and/or F exposure may be mediated by different gut microbes and their associated metabolites. [ABSTRACT FROM AUTHOR]

In this study, green phosphorescent Pt(II) complexes with N,N‐diphenyl‐6‐(1H‐pyrazol‐1‐yl)pyridin‐2‐amine (Ndpp) coordinated ligands, [Pt (Ndpp)Cl] 2a, [Pt (Ndpp)Pb, Pb = (prop‐1‐ynyl)benzene] 2b, and [Pt (Ndpp)CN] 2aCN were theoretically investigated by means of density functional theory and time‐dependent density functional theory calculations to reveal their marked distinct phosphorescence quantum yields. These complexes exhibit evident absorption bands in the 200–450 nm region but emit strong green light with marked differences of phosphorescence quantum yields. Compared with the complex 2a, the complex 2b possesses large oscillator strengths of absorption spectra, strong spin‐orbit coupling, and transition electric dipole moment, as well as small singlet‐triplet splitting energies, which conduces to enhancing its radiative decay. To illustrate the nonradiative decay process, the transition state (TS) between the triplet metal‐centered (3MC) state and the excited state (T1) was optimized. The 3MC state is found to be the minimum energy crossing point (MECP) between the T1 state and the S0 state. Compared with the complex 2a, the complex 2b possesses a much larger energy barrier to the MECP state from the T1 state, so it is strongly emissive in the green region. Besides, the introduction of CN substitutions on 2a is useful for enhancing the energy barrier to the thermal deactivation pathway of 3MLCT → TS → MECP. These results demonstrate that the modification of metal–ligand conjugation is an effective way to develop high‐performance phosphorescent materials. [ABSTRACT FROM AUTHOR]

The optimum conditions for extraction pigment from Black Potato were determined by using response surface method on the basis of ethanol concentration, reflux temperature, reflux time and ratio of solid to liquid four single factor tests The results showed that the optimal extraction condition was as folows: ethanol concentration 42.5%, reflux temperature 47°C,reflux time 47.5min, and ratio of solid to liquid 1 : Under these conditions, the measured absorbance of pigment was 0.413, compared with the predictive value of 0.416, the relative eror was 0.726% The result also indicated it was feasible to adopt response surface methodology to optimize the extraction condition. [ABSTRACT FROM AUTHOR]

Vp1 gene of O type foot-and-mouth diseases virus and M. tuberculosis HSP70 were expressed in methylotrophic yeast Pichia pastoris expression system. The results of cellular immune responses and humoral immune response were examined after BALB/c mice were immunized with fusion protein expressed in methylotrophic yeast Pichia pastoris. The genes was cloned into the vector pPICZalpha-A by routine molecular technique. The plasmid fusion (pPICZalphaA-vp1-HSP70) was created that HSP70 located downstream of VP1 gene of O type foot-and-mouth disease virus. Vp1 was expressed by fusing to the amino terminus of M. tuberculosis hsp70 in yeast Pichia pastoris. The recombined fusion plasmid was transformed into methylotrophic yeast Pichia pastoris X-33 by electrophoration. The recombinant transformants were selected by Zeocin and induced by the addition of methanol every 24h. The expressived product analyzed by SDS-PAGE and Western blotting. The result indicated that the fusion protein(vp1-HSP70) has specific antigenicity. Mice were inoculated transcutaneous three times at a two-weeks interval with fusion protein, PBS and conventional inactivated vaccines. To evaluate the prophylaxtic efficacy of fusion protein, Titers of antibodies was detected by ELISA and proliferation of lymphocytes were determined by MTT. The results indicated that fusion protein could elicit specific humoral immune and cellular immune responses. Compared with conventional inactivated vaccines, fusion protein elicited slightly lower FMDV antibody level but stronger T cell proliferation.

Aim: To analyze occupational health hazards exposure to doses lower than the Chinese occupational health standard in a selected VC polymerization plant in China, and also to elucidate the relationship between genetic polymorphisms and genetic susceptibility on liver lesions of workers exposed to vinyl chloride monomer(VCM)., Methods: In order to explore the mechanism of VCM-related health effects, we used a case-control design to investigate the association between the genetic polymorphisms of metabolic enzymes and liver lesions in workers occupationally exposed to VCM. Genotypes of CYP2E1, GSTT1, GSTM1, ALDH2 and ADH2 were identified using PCR and PCR-RFLP., Results: Even when the concentration of VCM was lower than the current Chinese occupational health standard, neurasthenia, pharyngeal irritation, liver ultrasonography abnormalities and hemoglobin disorders were significantly higher in exposure subjects compared to non-exposure subjects, and the relative risks (RR and 95% CI) were 1.74 (1.06-2.85), 1.97 (1.56-2.48), 10.69 (4.38-26.12), and 2.07 (1.20-3.57). CYP2E1 c1c2/c2c2 genotype was significantly associated with liver damages (OR 3.29, 95% CI 1.51-7.20, P<0.01)., Conclusion: The incidences of neurasthenia and liver ultrasonography abnormalities significantly increase when the cumulative exposure dose increases. The genotypes of metabolic enzymes (CYP2E1 c1c2/c2c2, null GSTT1 and ADH2 1-1) play important roles in VCM metabolism. Polymorphisms of CYP 2E1, GSTT1 and ADH2 may be a major reason of genetic susceptibility in VCM-induced hepatic damage.

A FAAS method was established for the determination of Na, K, Mg, Ca, Cu, Zn, Fe, Mn, Ni, Co, Pb, Cr, Cd, Ag and Au in Cynomorium songaricum after digestion with HNO3-HClO4 (phi 4:1) at 90-95 degrees C and at normal pressure. In this paper, the parameters in FAAS were studied. The analytical results of Na, K, Mg, Ca, Fe, Zn, Cu, Mn, Pb, Ni and Ag were 13,572.0, 14,260.0, 358.3, 168.3, 238.5, 19.4, 5.9, 3.4, 2.6, 1.3 and 0.4 microg x g(-1) respectively and Co, Cr, Cd and Au were not found in the samples. The results showed that the recovery of standard addition was 97.8%-104.5%, and the relative standard deviation (n = 9) was 0.2%-5.0%. The method is fast, simple and convenient. The results were satisfactory.