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Vibrational properties associated with the intra- and intermolecular bonding of the crystalline Dibenz[a,h]anthracene at low temperatures are investigated by Raman scattering. A complete characterization of phonon spectra is given for this material. In the 120-150 K temperature region, several lattice modes show abrupt changes of splitting and the discontinuities in the temperature shift, but no emergence of new modes. Moreover, the intensity ratio of I 68 / 38 is greater than 1 below 130 K. Meanwhile, the aromatic C-C stretching modes exhibit anomalous behaviors in frequencies, widths, and intensities at about 130 K. These spectroscopic results demonstrate a disorder-order transition occurred at about 130 K. However, the modes, corresponding to C-H out-of-plane bending, C-H in-plane bending, and/or C-H rocking, have no significant change in the whole temperature range. It indicates that the transition mainly results from the change of the tilt angle between the molecules. Our work is of great significance to understand the internal vibrational properties of Dibenz[a,h]anthracene, and it also provides considerable supports for the further study of this material., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Background: The aim of this study was to evaluate the long-term sequelae and cognitive profiles resulting from severe hand, foot, and mouth disease (HFMD) with central nervous system (CNS) involvement., Methods: 294 HFMD cases were included in a retrospective follow-up study. Physical examinations were conducted. The Chinese Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV) was used to assess intelligence., Results: 58 mild HFMD cases and 99 severe HFMD cases with mild CNS involvement did not present any neurological sequelae. In comparison, the sequelae incidence for severe HFMD with more severe CNS complications was 50.0%. The proportion of full-scale intelligence quotient (FSIQ) impairment was 45.0%. In the 2:6-3:11 age group, severe HFMD with more severe CNS complications and lower maternal education level were risk factors for verbal comprehension disorder. Urban-rural residence and lower paternal education level were risk factors for FSIQ disorder. Furthermore, in the 4:0-6:11 age group, severe HFMD with more severe CNS complication was a risk factor for visual spatial disorder and fluid reasoning disorder. Lower paternal education level was a risk factor for FSIQ disorder., Conclusion: Early assessment and intervention among severe HFMD patients with more severe CNS involvement at a very young age will prove beneficial for their future performance., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Wilforine, a compound of sesquiterpene alkaloids isolated from Tripterygium wilfordii, exhibits excellent insecticidal activity against Mythimna separata. In order to clarify the action mechanism of wilforine, the plasma membrane calcium transporting ATPase (PMCA) and inositol 1,4,5-trisphosphate receptor (IP 3 R) from M. separata were studied. Results showed that the open reading frame of MsIP 3 R and MsPMCA were 8118 bp and 3438 bp in length, as well as encoded 2706 and 1146 amino acids, respectively. Multiple sequence alignment and phylogenetic analysis revealed that the MsIP 3 R and MsPMCA had high homology with the IP 3 R and PMCA of other insects, but had low similarity with those of mammals, which means the IP 3 R and PMCA have potential to be the novel targets of insecticides with high selectivity between mammals and insects. Both MsIP 3 R and MsPMCA genes existed throughout the life cycle of M. separata, and were all predominantly expressed in somatic muscle of fifth-instar larvae and the adults. The susceptibilities of PMCA-silenced M. separata to wilforine were significantly lower than that of the normal M. separata, which illustrates that PMCA could be one of the targets of wilforine. However, the susceptibilities of IP 3 R-silenced M. separata to wilforine did not change significantly compared with the susceptibilities of normal M. separata, which shows that wilforine may not interact with the IP 3 R protein. These findings provide clues for elucidating the insecticidal mechanism of wilforine., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare Vitamin D (Vit D) levels in children with epilepsy on valproate monotherapy with healthy controls., Methods: A meta-analysis performed on articles identified from PubMed and Web of Science online databases evaluated using National Institute of Health National Heart, Lung, and Blood Institute Study Quality Assessment Tools. Subgroup analyses and publication bias assessments were also performed., Results: Eleven publications were eligible based on inclusion/exclusion criteria for the meta-analysis. Results noted a decrease in the mean Vit D level in children with epilepsy on valproate monotherapy compared with healthy children with a Standard Mean Difference = -0.313 [-0.457, -0.169]. Cumulative meta-analysis showed progressive negative effect of valproate therapy on Vit D levels across time. Other antiepileptic medications caused a similar effect on Vit D status. There was no evidence of publication bias in the analyses. Type of study design and country of origin introduced heterogeneities into the meta-analyses., Conclusion: This meta-analysis provides evidence that long-term therapy with valproate causes a decrease in Vit D levels in children. Therefore, in children with a seizure disorder on long-term valproate therapy, 25-OH-Vit D levels should be monitored and appropriate supplementation implemented if levels are deficient., (Copyright © 2019 British Epilepsy Association. All rights reserved.)

This work illustrates an accurate method for determination of Se by electrolytic hydride generation technique based on a novel carbon paste electrode for sample introduction combined with atomic fluorescence spectral analysis. The studies show that Se(IV) can be converted efficiently to SeH 2 on an L -cysteine modified carbon paste electrode (CMCPE), which has never been reported before. Significantly, generation from Se(IV) implies that the use of carbon paste electrode-based electron-induced hydride generation system to achieve efficiency is almost 90% to that obtained by chemical hydride generation, and the response obtained from CMCPE is 2 and 3 times of that from the Pb and graphite electrode, respectively. Results also display that the lifetime and the stability of the CMCPE is superior to that of L -cysteine ornamented graphite electrode fabricated by covalently bonding. Under the optimal conditions, a low concentration limit of detection 0.065µgL -1 of Se(IV) is achieved. The repeatability denoted as % RSD is 2.2% for 1.0μgL -1 Se(IV). The utility of the studied method is compared with certified reference materials as well as several edible samples. The advantages and limitations of this method, compared with existing techniques, are also discussed., (Copyright © 2017 Elsevier B.V. All rights reserved.)

A novel non-chromatographic speciation technique for ultra-trace arsenite [As(III)] and total arsenic (tAs) in Chinese herbal medicine (CHM) is developed and validated by electrolytic hydride generation (EHG) coupled with atomic fluorescence spectrometry (AFS). The studies show that As(III) can be converted efficiently to AsH3 on an L -cysteine modified carbon paste electrode (CMCPE), which has never been reported before. Significantly, other arsenic species such as arsenate [As(V)], monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) do not form any or only less volatile hydrides at low applied current mode (<1.0 A). The results also demonstrate that L -cysteine and graphite powder play different roles in the electrolytic generation of AsH 3 . Comparing with the traditional graphite electrode, CMCPE has better stability, sensitivity and interference tolerance. Under the optimal conditions, the limit of detection (LOD) of tAs and As(III) for this method are 0.087µgL -1 and 0.095µgL -1 respectively. The accuracy of the method is verified through the analysis of reference materials (CRM 08231 and SRM1568a), and the proposed method has been applied satisfactorily to the determination of As(III) and tAs in several CHM samples., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Paris saponins possess anticancer, anti-inflammatory, and antiviral effects. However, the anticancer effect of Paris saponins has not been well elucidated and the mechanisms underlying the potential function of Paris saponins in cancer therapy are needed to be further identify. In this study, we report that saponin compounds isolated from Paris polyphylla exhibited antitumor activity against breast cancer cell lines, MCF-7 and MDA-MB-231. Paris saponin XA-2 induced apoptosis in both cell lines, as evidenced by the activation of caspases and cleavage of Poly (ADP-ribose) polymerase. The ability of XA-2 to induce autophagy was confirmed by acridine orange staining, accumulation of autophagosome-bound Long chain 3 (LC3)-II, and measurement of autophagic flux. XA-2-induced autophagy was observed to promote apoptosis by the combined treatment of breast cancer cell lines with XA-2 and autophagy inhibitors 3-methyladenine and bafilomycin A1, respectively. Moreover, we report a decrease in the levels of Akt/mTOR signaling pathway proteins, such as the phosphorylated forms of Akt, mTOR, P70S6K, and eukaryotic translation initiation factor 4E-binding protein 1 (4EBP1). Taken together, these results provide important insights explaining the anticancer activity of Paris saponins and the potential development of XA-2 as a new therapeutic agent., (Copyright © 2017 Elsevier B.V. All rights reserved.)

This work describes a novel non-chromatographic approach for the accurate and selective determining As species by modified graphite electrode-based electrolytic hydride generation (EHG) for sample introduction coupled with atomic fluorescence spectrometry (AFS) detection. Two kinds of sulfydryl-containing modifiers, l-cysteine (Cys) and glutathione (GSH), are used to modify cathode. The EHG performance of As has been changed greatly at the modified cathode, which has never been reported. Arsenite [As(III)] on the GSH modified graphite electrode (GSH/GE)-based EHG can be selectively and quantitatively converted to AsH3 at applied current of 0.4A. As(III) and arsenate [As(V)] on the Cys modified graphite electrode (Cys/GE) EHG can be selectively and efficiently converted to arsine at applied current of 0.6A, whereas monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) do not form any or only less volatile hydrides under this condition. By changing the analytical conditions, we also have achieved the analysis of total As (tAs) and DMA. Under the optimal condition, the detection limits (3s) of As(III), iAs and tAs in aqueous solutions are 0.25μgL(-1), 0.22μgL(-1) and 0.10μgL(-1), respectively. The accuracy of the method is verified through the analysis of standard reference materials (SRM 1568a)., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Cyclin D1 messenger RNA expression was investigated in differentiated proliferation-competent primary cultures of adult rat hepatocytes. Periodic expression was observed during the 12-day growth cycle (approximately two population doublings). Upon reaching a quiescent G(o)-state, 4-kb cyclin D1 mRNA levels were undetectable. When G(o) cultures were shifted into defined media without or with 0.2-0.8 nM TGF-alpha, conditions that reinitiate full proliferative transitions synchronously, cyclin D1 mRNA levels were elevated 1.2-4.6-fold, respectively. These findings support the hypothesis that hepatic mitogens stimulate periodic cyclin mRNA expression directly.

Normal and malignant hepatocytes were transfected during log phase culture with a nested series of DNA plasmids containing 5'-flanking regions of the rat liver-specific acute phase plasma proteinase alpha 1-inhibitor III (alpha 1 I3) gene. Under these conditions, luciferase reporter gene expression in primary adult rat and mouse hepatocytes was 10-fold higher than luciferase expression in hepatoma lines (human HepG2 and Hep3B; rat FAZA). Optimal expression in primary rat hepatocytes required regions stretching 2214 bp 5'-upstream of the transcription start site. Shorter 5'-flanking sequences were optimal for expression in hepatoma cells (-1025 and -186 bp for rat and human lines, respectively) and primary mouse hepatocytes (-225 bp). In contrast, regions from -186 to -225 bp drove luciferase expression in primary rat hepatocytes, but only 20-75% of optimal levels. Qualitative differences were unaccounted for by non-equivalent uptake of plasmid DNA, suggesting that tissue specific gene expression is regulated differently in normal and malignant cells, and with apparent species specificity.