Chemical composition of the volatile oil of Chenopodium ambrosioides L. from Mianyang in Sichuan Province of China and its sub-chronic toxicity in mice

Purpose: To determine the chemical constituents of the volatile oil of Chenopodium ambrosioides L. from Mianyang in Sichuan Province of China, and assess the sub-chronic toxicity of the volatile oil in mice.Methods: The volatile chemical components were analyzed by gas chromatography-mass spectrometry (GC-MS). Sixty Kunming mice were divided into six groups of ten mice each. One group served as control (no treatment), two groups were orally administered ρ-cymene at doses of 3 and 7 mg/kg, respectively, for 27 days, while three groups received the volatile oil at doses of 10, 25 and 40 mg/kg, respectively, for the same duration. Sub-chronic toxicity in the mice was evaluated by observing their general behavior, measuring serum levels of aspartate transaminase (AST) and alanine transaminase (ALT), evaluating liver, heart, kidney and thymus indices, and assessing the histological morphology of the organs.Results: The volatile oil contained 14 chemical components, of which α-terpinene and ρ-cymene accounted for 32.89 and 24.25 %, respectively. The volatile oil caused significant (p < 0.05) increase in liver index, and serum AST and ALT levels, and also induced distinct morphological changes in mouse liver, heart and kidney.Conclusion: The main volatile components of the oil are α-terpinene and ρ-cymene. The volatile oil showed dose-dependent toxicity in mice, thus lending some support for the safe use of C. ambrosioides in traditional medicine. Keywords: Chenopodium ambrosioides, Volatile oil, Oral toxicity, AST and ALT, Histopathological change

Safety and efficacy of rapid withdrawal of anti-seizure medication during long-term video-EEG monitoring

ObjectiveAnti-seizure medications (ASMs) are often withdrawn during long-term video-EEG monitoring (LTM) to allow pre-surgical evaluation. Herein, we evaluated the safety and efficacy of ultra-rapid withdrawal (URW) and rapid withdrawal (RW) of ASMs in an epilepsy monitoring unit (EMU).MethodsThis retrospective study examined all consecutive patients admitted to our EMU between May 2021 and October 2022. Patients were classified into the URW and RW groups according to the way ASMs were withdrawn. We compared the efficacy and safety of the procedures used in the groups in terms of duration of LTM, latency to the first seizure, and incidence of focal to bilateral tonic–clonic seizures (FBTCS), seizure clusters (SC), and status epilepticus (SE).ResultsOverall, 110 patients (38 women) were included. The mean age of patients at the time of LTM was 29 years. All medications were stopped on admission for monitoring in the URW group (n = 75), while in the RW group (n = 35) ASMs were withdrawn within 1 day. In both groups, the duration of LTM was approximately 3 days: URW group (2.9 ± 0.5 days) and RW group (3.1 ± 0.8 days). The latency to the first seizure was significantly different between the two groups; however, there were no differences between the two groups in terms of the distribution of FBTCS, SC, or SE, number of seizures, and the requirement for intravenous rescue medication was low.ConclusionThe rapid withdrawal of ASMs to provoke seizures during monitoring for pre-surgical evaluation following the URW protocol was as effective and safe as with RW. Ultra-rapid ASM withdrawal has the benefits of reducing LTM duration and shortening the time to first seizure compared to rapid medication tapering

Knowledge of and attitudes towards erosive tooth wear among students of two Chinese universities

Background: To assess the knowledge of and attitudes towards erosive tooth wear among dental, medical, and non-medical university students of two Chinese universities. Methods: A questionnaire containing 15 questions on knowledge of erosive tooth wear and 10 questions on attitudes towards erosive tooth wear was designed, and its psychometric properties (reliability and validity) were analysed in a pilot study (n = 120 students). The following 3 groups of university students (n = 635) were recruited based on a convenience sampling technique and were distributed the questionnaire via an online survey system: Dental students (DSs), medical students (MSs), and non-medical students (NSs). Differences in the scores between groups and genders were analysed by one-way analysis of variance (ANOVA). The Pearson correlation coefficient was used to determine the association between the knowledge and attitude scores (P < 0.05). Results: The questionnaire was found to be reliable, valid and reproducible. A total of 435 students participated in this study (response rate: 69.6%). The knowledge score of the DSs (11.5 ± 3.4) was significantly higher than those of the NSs (5.5 ± 4.0) and MSs (6.1 ± 4.0) (P < 0.001). The attitude score of the DSs (45.2 ± 6.5) was significantly higher than those of the NSs (41.1 ± 6.9) and MSs (41.8 ± 6.4) (P < 0.001). The majority of DSs expressed attitudes that were more accurate and positive than those expressed by the other 2 groups. The attitude score was positively correlated with the knowledge score (r = 0.237, P < 0.001). Conclusions: Dental students had more accurate knowledge of and more positive attitudes towards erosive tooth wear than medical and non-medical students. In this population, a positive correlation was established between knowledge of and attitudes towards erosive tooth wear

1,2,4,5-Tetra­phenyl-1H-imidazole

The asymmetric unit of the title compound, C27H20N2, contains two independent mol­ecules, A and B. In both mol­ecules, the N atom in the 1-position and the C atom in the 5-position are statistically disordered [as 0.571 (8):0.429 (8) in A and 0.736 (9):0.264 (9) in B]. The phenyl rings in the 1-, 2-, 4- and 5-positions in A are twisted from the central imidazole ring by 84.3 (2), 21.6 (2), 21.5 (2) and 75.7 (2)°, respectively. The corresponding dihedral angles in B are 85.5 (2), 3.8 (2), 2.4 (2) and 81.7 (2)°, respectively

Molecular characterization of CHST11 and its potential role in nacre formation in pearl oyster Pinctada fucata martensii

Background: C4ST-1 catalyzes the transfer of sulfate groups in the sulfonation of chondroitin during chondroitin sulfate synthesis. Chondroitin sulfate consists of numerous copies of negatively charged sulfonic acid groups that participate in the nucleation process of biomineralization. In the present study, we obtained two CHST11 genes (PmCHST11a and PmCHST11b) which encoded the C4ST-1 and explored the functions of these genes in the synthesis of chondroitin sulfate and in the formation of the nacreous layer of shells. Results: Both PmCHST11a and PmCHST11b had a sulfotransferase-2 domain, a signal peptide and a transmembrane domain. These properties indicated that these genes localize in the Golgi apparatus. Real-time PCR revealed that both PmCHST11a and PmCHST11b were highly expressed in the central zone of the mantle tissue. Inhibiting PmCHST11a and PmCHST11b via RNA interference significantly decreased the expression levels of these genes in the central zone of the mantle tissue and the concentration of chondroitin sulfate in extrapallial fluid. Moreover, shell nacre crystallized irregularly with a rough surface after RNA interference. Conclusions: This study indicated thatPmCHST11a and PmCHST11b are involved in the nacre formation of Pinctada fucata martensii through participating in the synthesis of chondroitin sulfate

Development of SSR marker by RNA-seq and its application in genotyping pearl sac in pearl oyster Pinctada fucata martensii

Background: Pearl oyster Pinctada fucata martensii is cultured for producing round nucleated pearls. Pearl production involves a surgical operation where a mantle tissue graft from a donor oyster and a round nucleus are implanted in the gonad of a host oyster. Whether the mantle graft implanted in the gonad of a host oyster contributes to the formation of a pearl sac that secretes pearl nacre to form a pearl should be determined. In April 2012, two full-sib families were separately used as donor and host oysters for a nucleus insertion operation. The pearl sac was sampled from the host oysters at day 60 after nucleus operation. A large number of simple sequence repeat (SSR) markers were developed using Illumina HiSeq\u2122 2000 platform. The two full-sib families were also used to mine diagnostic SSR markers for genotyping donor oyster, host oyster, and pearl sac. Results: A total of 3168 microsatellite lociwere identified in 39,078 unigenes, and 1977 SSR primerswere designed by Primer 3.0. Forty-seven SSR primers were validated, and the rate of successful amplification was 72.3%. Two diagnostic SSR primers could successfully genotype pearl sac, donor oyster, and host oyster. Donor and host oysters were both homogenous, and the alleles in pearl sac were identical to those in donor and host oysters. Conclusions: The present results confirmed that themantle graft implanted in the gonad of host oyster contributed to the formation of the pearl sac in pearl oyster P. fucata martensii

Flexoelectricity-stabilized ferroelectric phase with enhanced reliability in ultrathin La:HfO2 films

Doped HfO2 thin films exhibit robust ferroelectric properties even for nanometric thicknesses, are compatible with current Si technology and thus have great potential for the revival of integrated ferroelectrics. Phase control and reliability are core issues for their applications. Here we show that, in (111)-oriented 5%La:HfO2 (HLO) epitaxial thin films deposited on (La0.3Sr0.7)(Al0.65Ta0.35)O3 substrates, the flexoelectric effect, arising from the strain gradient along the films normal, induces a rhombohedral distortion in the otherwise Pca21 orthorhombic structure. Density functional calculations reveal that the distorted structure is indeed more stable than the pure Pca21 structure, when applying an electric field mimicking the flexoelectric field. This rhombohedral distortion greatly improves the fatigue endurance of HLO thin films by further stabilizing the metastable ferroelectric phase against the transition to the thermodynamically stable non-polar monoclinic phase during repetitive cycling. Our results demonstrate that the flexoelectric effect, though negligibly weak in bulk, is crucial to optimize the structure and properties of doped HfO2 thin films with nanometric thicknesses for integrated ferroelectric applications