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The escalating obesity epidemic and aging population have propelled metabolic dysfunction-associated steatohepatitis (MASH) to the forefront of public health concerns. The activation of FXR shows promise to combat MASH and its detrimental consequences. However, the specific alterations within the MASH-related transcriptional network remain elusive, hindering the development of more precise and effective therapeutic strategies. Through a comprehensive analysis of liver RNA-seq data from human and mouse MASH samples, we identified central perturbations within the MASH-associated transcriptional network, including disrupted cellular metabolism and mitochondrial function, decreased tissue repair capability, and increased inflammation and fibrosis. By employing integrated transcriptome profiling of diverse FXR agonists-treated mice, FXR liver-specific knockout mice, and open-source human datasets, we determined that hepatic FXR activation effectively ameliorated MASH by reversing the dysregulated metabolic and inflammatory networks implicated in MASH pathogenesis. This mitigation encompassed resolving fibrosis and reducing immune infiltration. By understanding the core regulatory network of FXR, which is directly correlated with disease severity and treatment response, we identified approximately one-third of the patients who could potentially benefit from FXR agonist therapy. A similar analysis involving intestinal RNA-seq data from FXR agonists-treated mice and FXR intestine-specific knockout mice revealed that intestinal FXR activation attenuates intestinal inflammation, and has promise in attenuating hepatic inflammation and fibrosis. Collectively, our study uncovers the intricate pathophysiological features of MASH at a transcriptional level and highlights the complex interplay between FXR activation and both MASH progression and regression. These findings contribute to precise drug development, utilization, and efficacy evaluation, ultimately aiming to improve patient outcomes.

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Generating new molecules with the desired physical or chemical properties is the key challenge of computational material design. Deep learning techniques are being actively applied in the field of data-driven material informatics and provide a promising way to accelerate the discovery of innovative materials. In this work, we utilize an invertible graph generative model to generate hypothetical promising high-temperature polymer dielectrics. A molecular graph generative model based on the invertible normalizing flow is trained on a data set containing 250k polymer molecular graphs (mostly generated by an RNN-based generative model) to learn the invertible transformations between latent distributions and molecular graph structures. When generating molecular graphs, a sample vector is drawn from the latent space, and then an adjacency tensor and node attribute matrix are generated through two invertible flows in two steps and assembled into a molecular graph. The model has the merits of exact likelihood training and an efficient one-shot generation process. The learned latent space is used to generate polymers with a high glass-transition temperature (Tg) and a wide band gap (Eg) for the application of high-temperature energy storage film capacitors. This work contributes to the efficient design of high-temperature polymer dielectrics by using deep generative models.

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The further electrification of various fields in production and daily life makes it a topic worthy of exploration to improve the performance of capacitors for a long time, including thin-film capacitors. The discharge energy density of thin-film capacitors that serves as one of the important types directly depends on electric field strength and the dielectric constant of the insulation material. However, it has long been a great challenge to improve the breakdown strength and dielectric constant simultaneously. Considering that boron nitride nanosheets (BNNS) possess superior insulation and thermal conductivity owing to wide band gap and 2-dimensional structure, a bilayer polymer film is prepared via coating BNNS by solution casting on surface of polyethylene terephthalate (PET) films. By revealing the bandgap and insulating behavior with UV absorption spectrum, leakage current, and finite element calculation, it is manifested that nanocoating contributes to enhance the bandgap of polymer films, thereby suppressing the charge injection by redirecting their transport from electrodes. Worthy to note that an ultrahigh breakdown field strength (~ 736 MV m-1), an excellent discharge energy density (~ 8.77 J cm-3) and a prominent charge-discharge efficiency (~ 96.51%) are achieved concurrently, which is ascribed to the contribution of BNNS ultrathin layer. In addition, the modified PET films also have superior comprehensive performance at high temperatures (~ 120 °C). The materials and methods here selected are easily accessible and facile, which are suitable for large-scale roll-to-roll process production, and are of certain significance to explore the methods about film modification suitable for commercial promotion.

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The medical use of molecular hydrogen, including hydrogen-rich water and hydrogen gas, has been extensively explored since 2007. This article aimed to demonstrate the trend in medical research on molecular hydrogen. A total of 1126 publications on hydrogen therapy were retrieved from the PubMed database until July 30, 2021. From 2007 to 2020, the number of publications in this field had been on an upward trend. Medical Gas Research, Scientific Report and Shock have contributed the largest number of publications on this topic. Researchers by the name of Xue-Jun Sun, Ke-Liang Xie and Yong-Hao Yu published the most studies in the field. Analysis of the co-occurrence of key words indicated that the key words "molecular hydrogen," "hydrogen-rich water," "oxidative stress," "hydrogen gas," and "inflammation" occurred most frequently in these articles. "Gut microbiota," "pyroptosis," and "COVID-19" occurred the most recently among the keywords. In summary, the therapeutic application of molecular hydrogen had attracted much attention in these years. The advance in this field could be caught up by subscribing to relevant journals or following experienced scholars. Oxidative stress and inflammation were the most important research directions currently, and gut microbiota, pyroptosis, and coronavirus disease 2019 might become hotspots in the future.

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With the improvement of living standards and changes in working style, the prevalence of abnormal glucose and lipid metabolism in humans is increasing in modern society. Clinically, the related indicators are often improved by changing the lifestyle and/or taking hypoglycemic and lipid-lowering drugs, but there are no therapeutic drugs for disorders of glucose and lipid metabolism at present. Hepatitis C virus core protein binding protein 6(HCBP6) is a newly discovered target that can regulate triglyceride and cholesterol content according to level oscillations in the body, thereby regulating abnormal glucose and lipid metabolism. Relevant studies have shown that ginsenoside Rh_2 can significantly up-regulate the expression of HCBP6, but there are few studies on the effect of Chinese herbal medicines on HCBP6. Moreover, the three-dimensional structural information of HCBP6 has not been determined and the discovery of potential active components acting on HCBP6 is not rapidly advanced. Therefore, the total saponins of eight Chinese herbal medicines commonly used to regulate abnormal glucose and lipid metabolism were selected as the research objects to observe their effect on the expression of HCBP6. Then, the three-dimensional structure of HCBP6 was predicted, followed by molecular docking with saponins in eight Chinese herbal medicines to quickly find potential active components. The results showed that all total saponins tended to up-regulate HCBP6 mRNA and protein expression, where gypenosides showed the optimum effect on up-regulating HCBP6 mRNA and ginsenosides showed the optimum effect on up-regulating HCBP6 protein expression. Reliable protein structures were obtained after the prediction of protein structures using the Robetta website and the evaluation of the predicted structures by SAVES. The saponins from the website and literature were also collected and docked with the predicted protein, and the saponin components were found to have good binding activity to the HCBP6 protein. The results of the study are expected to provide ideas and methods for the discovery of new drugs from Chinese herbal medicines to regulate glucose and lipid metabolism.

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To improve the quality control methods of Poria and develop and utilize its resources fully, alkaline extraction was used in this study to determine the yield and content of alkali-soluble polysaccharides of Poria. The alkali-soluble extracts of Poria were obtained according to the optimum extraction conditions on the basis of single-factor test, and 30 batches of samples were determined. The structure and chemical composition of the alkali-soluble extracts was characterized by high-performance gel permeation chromatography(HPGPC), Fourier transform infrared spectrometry(FT-IR), nuclear magnetic resonance(NMR) spectroscopy and high-performance liquid chromatography(HPLC) with 1-phenyl-3-methyl-5-pyrazolone(PMP-HPLC). The results showed that the content of the alkali-soluble extracts was in the range of 46.98%-73.86%. The main component was ß-(1→3)-glucan, and its molecular mass was about 1.093×10~5. Further, the content of alkali-soluble polysaccharides of Poria was measured by UV-Vis spectrophotometry and HPLC coupled with the evaporative light scattering detector(HPLC-ELSD), and 30 batches of samples were measured. The results indicated that the content of alkali-soluble polysaccharides determined by UV-Vis spectrophotometry was in the range of 73.70%-92.57%, and the content of samples from Hubei province was slightly higher than that from Yunnan province, Anhui province and Hunan province. The content of alkali-soluble polysaccharides determined by HPLC-ELSD was in the range of 51.42%-76.69%, and the samples from Hunan province had slightly higher content than that from the other three provinces. The content determined by UV-Vis spectrophotometry was higher than that by HPLC-ELSD. However, the content determined by HPLC-ELSD was close to that of alkali-soluble extract, which could accurately characterize the content of alkali-soluble polysaccharides in Poria, and the method was simple and repeatable. Therefore, it is recommended that the quantitative analysis method for alkali-soluble extract and alkali-soluble polysaccharides by HPLC-ELSD be used in the quality standards of Poria in Chinese Pharmacopeia.

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BACKGROUND AND PURPOSE: Early identification of cerebrovascular atherosclerotic ischemic stroke is necessary for accurate treatment and clinical research. AIMS: To identify novel predictors and build a predictive model of ischemic strokes due to cerebrovascular atherosclerosis. METHOD: MIMIC-IV database was used to search for clinical data of patients with ischemic stroke. Included patients were divided into two groups according to their etiologies. Univariate and multivariate logistic regressions were used to build the predictive model, and the model reliability parameters were calculated. The cut-off value for the model was selected according to the Youden index. Clinical data from the Neurovascular Center of Changhai Hospital were used to verify the predictive model. RESULTS: Logistical regressions showed a positive correlation between advanced age, peripheral atherosclerosis, history of transient ischemia, and the diagnosis of ischemic strokes due to cerebrovascular atherosclerosis. The history of atrial fibrillation, levels of the National Institutes of Health Stroke Scale, serum potassium, and activated partial thromboplastin time were negatively correlated to the diagnosis of cerebrovascular atherosclerotic ischemic stroke. The predictive model was constructed from logistic regression results, and the area under the curve was 0.764. The cut-off value for the model was set at 0.089 to achieve the highest Youden index, with sensitivity and specificity of 75.9% and 64.1%. Clinical verification of the model revealed that the sensitivity and specificity of the model were 52.5% and 93.0% respectively. CONCLUSION: The efficacy of the predictive model was acceptable as an aid in predicting cerebrovascular atherosclerotic ischemic stroke.

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Aims: This study aimed to build a prediction model to early diagnose intracranial atherosclerosis (ICAS)-related large vascular occlusion (LVO) in acute ischemic stroke patients before digital subtractive angiography. Methods: Patients enrolled in the DIRECT-MT trial (NCT03469206) were included in our secondary analysis and distributed into ICAS-LVO and non-ICAS-LVO groups. We also retrieved demographic data, medical histories, clinical characteristics, and pre-operative imaging data. Hypothesis testing was used to compare data of the two groups, and univariate logistic regression was used to identify the predictors of ICAS-LVO primarily. Then, we used multivariate logistic regression to determine the independent predictors and formulate the prediction model. Model efficacy was estimated by the area under the receiver operating characteristic (ROC) curve (AUC) and diagnostic parameters generated from internal and external validations. Results: The subgroup analysis included 45 cases in the ICAS-LVO group and 611 cases in the non-ICAS-LVO group. Variates with p < 0.1 in the comparative analysis were used as inputs in the univariate logistic regression. Next, variates with p < 0.1 in the univariate logistic regression were used as inputs in the multivariate logistic regression. The multivariate logistic regression indicated that the atrial fibrillation history, hypertension and smoking, occlusion located at the proximal M1 and M2, hyperdense artery sign, and clot burden score were related to the diagnosis of ICAS-LVO. Then, we constructed a prediction model based on multivariate logistics regression. The sensitivity and specificity of the model were 84.09 and 74.54% in internal validation and 73.11 and 71.53% in external validation. Conclusion: Our current prediction model based on clinical data of patients from the DIRECT-MT trial might be a promising tool for predicting ICAS-LVO.

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The ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS~E) technology was employed to compare the chemical components between the aerial and underground parts of Coptis chinensis samples from different batches. According to the retention time, molecular ion peak, and LC-MS~E fragment information of the reference substances and available literature, we identified a total of 40 components. Thirty-three and 31 compounds were respectively identified in the underground part(taproots) and the aerial part(stems and leaves) of C. chinensis. Among them, 24 compounds, including alkaloids(e.g., berberine and jatrorrhizine) and phenolic acids(e.g., chlorogenic acid, quinic acid, and tanshinol), were common in the two parts. In addition, differential components were also identified, such as magnoline glucoside in the underground part and(±) lariciresionol-4-ß-D-glucopyranoside in the aerial part. The analysis of fragmentation pathways based on spectra of reference substances indicated the differences among samples of different batches. Furthermore, we performed the principal component analysis(PCA) for the peak areas of C. chinensis in different batches. The results showed that the underground part and the aerial part were clearly clustered into two groups, indicating that the chemical components contained in the two parts were different. Furthermore, the results of partial least squares discriminant analysis(PLS-DA) identified 31 differential compounds(VIP value>1) between the underground part and the aerial part, mainly including alkaloids, phenolic acids, lignans, and flavonoids. This study proves that C. chinensis possesses great development potential with multiple available compounds in stems and leaves. Moreover, it sheds light on for the development and utilization of non-medicinal organs of C. chinensis and other Chinese medicinal herbs.

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BACKGROUND AND PURPOSE: DIRECT-MT showed that endovascular thrombectomy was noninferior to thrombectomy preceded by intravenous alteplase with regard to functional outcome in patients with acute ischemic stroke. In this post hoc analysis, we examined whether infarct size modified the effect of alteplase. METHODS: All patients with baseline Alberta Stroke Program Early Computed Tomography Score (ASPECTS) grades were included. The primary outcome was the 90-day modified Rankin Scale (mRS) score. Multivariate ordinal logistic regression analysis was used to calculate the adjusted common odds ratio (OR) for better functional outcome based on the mRS for thrombectomy alone versus combination therapy. An interaction term was entered to test for an interaction with baseline ASPECTS subgroups: 0-4 versus 5-7 versus 8-10. RESULTS: Of 649 patients, 323 (49.8%) were in the thrombectomy-alone group and 326 (50.2%) in the combination-therapy group. There was no significant treatment-by-trichotomized ASPECTS interaction with alteplase prior to endovascular treatment for the primary endpoint of ordinal mRS (p-value interaction term relative to ASPECTS 8-10: ASPECTS 0-4, p = 0.386; ASPECTS 5-7, p = 0.936). Adjusted common ORs for improvement in the 90-day mRS with thrombectomy alone compared with combination therapy were 1.99 (95% confidence interval = 0.72-5.46) for ASPECTS 0-4, 1.07 (0.62-1.86) for ASPECTS 5-7, and 1.03 (0.74-1.45) for ASPECTS 8-10. There was no significant difference in the safety outcomes between the two groups. CONCLUSIONS: Baseline infarct size may not modify the effect of alteplase prior to endovascular thrombectomy with regard to favorable functional outcomes and adverse events.

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With the development of advanced electronic devices and electric power systems, polymer-based dielectric film capacitors with high energy storage capability have become particularly important. Compared with polymer nanocomposites with widespread attention, all-organic polymers are fundamental and have been proven to be more effective choices in the process of scalable, continuous, and large-scale industrial production, leading to many dielectric and energy storage applications. In the past decade, efforts have intensified in this field with great progress in newly discovered dielectric polymers, fundamental production technologies, and extension toward emerging computational strategies. This review summarizes the recent progress in the field of energy storage based on conventional as well as heat-resistant all-organic polymer materials with the focus on strategies to enhance the dielectric properties and energy storage performances. The key parameters of all-organic polymers, such as dielectric constant, dielectric loss, breakdown strength, energy density, and charge-discharge efficiency, have been thoroughly studied. In addition, the applications of computer-aided calculation including density functional theory, machine learning, and materials genome in rational design and performance prediction of polymer dielectrics are reviewed in detail. Based on a comprehensive understanding of recent developments, guidelines and prospects for the future development of all-organic polymer materials with dielectric and energy storage applications are proposed.

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The dried fruit body of Phylloporia ribis(Hymenochaetaceae), which prefers to live on the stumps of Lonicera japonica(Caprifoliaceae), has a variety of activities, whereas its pharmacodynamic material basis is not completely clear and there are few reports on its quality control and evaluation. In this study, an UPLC-Q-TOF-MS method was used to analyze the nucleosides and nucleobases in P. ribis and a HPLC method was established for simultaneous determination of 10 nucleosides and nucleobases. MS and MS/MS data were acquired in positive ion mode. Based on the data comparison of the sample and the reference substance, the literature data and the compound databases of ChemSpider and PubChem, 18 nucleosides and nucleobases were identified qualitatively from the water extract of P. ribis for the first time. After optimization, the HPLC was performed using a Welch Ultimate AQ C_(18) column(4.6 mm×250 mm, 5 µm) by gradient elution with acetonitrile and water as mobile phase, the flow rate of 1.0 mL·min~(-1), the detection wavelength of 260 nm, and the column temperature of 30 ℃. Through the investigation of the extraction method, solvent and time, it was determined that the test solution should be obtained by cold water extraction for 18 h. At the present HPLC conditions, 10 components of uracil, cytidine, hypoxanthine, uridine, thymine, inosine, guanosine, 2'-deoxyinosine, 2'-deoxyguanosine and thymidine could be well separated(R > 1.5) and showed good linearity(r > 0.999 9) in the concentration ranges of 0.247-24.7, 0.283-28.3, 0.273-27.3, 0.256-25.6, 0.257-25.7, 0.318-31.8, 0.245-24.5, 0.267-26.7, 0.250-25.0 and 0.267-26.7 mg·L~(-1), respectively. The average reco-veries of 10 components were 95.78%-104.5%, and the RSDs were 2.2%-5.2%(n=6). The contents of 10 nucleosides and nucleobases in different samples of P. ribis varied greatly, which were 0.021-0.122, 0.004-0.029, 0.014-0.226, 0.009-0.442, 0.003-0.014, 0.002-0.146, 0.007-0.098, 0-0.054, 0.005-0.069, 0.004-0.081 and 0.072-1.28 mg·g~(-1) for uracil, cytidine, hypoxanthine, uridine, thymine, inosine, guanosine, 2'-deoxyinosine, 2'-deoxyguanosine, thymidine and total 10 components, respectively. These results demonstrated that the components had significant differences in the internal quality, and good quality control was needed to ensure the medical efficacy. This study provides a scientific basis for the discovery of pharmacodynamic ingredients, quality control and evaluation of P. ribis.

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Recently, sensors that can imitate human skin have received extensive attention. Capacitive sensors have a simple structure, low loss, no temperature drift, and other excellent properties, and can be applied in the fields of robotics, human-machine interactions, medical care, and health monitoring. Polymer matrices are commonly employed in flexible capacitive sensors because of their high flexibility. However, their volume is almost unchanged when pressure is applied, and they are inherently viscoelastic. These shortcomings severely lead to high hysteresis and limit the improvement in sensitivity. Therefore, considerable efforts have been applied to improve the sensing performance by designing different microstructures of materials. Herein, two types of sensors based on the applied forces are discussed, including pressure sensors and strain sensors. Currently, five types of microstructures are commonly used in pressure sensors, while four are used in strain sensors. The advantages, disadvantages, and practical values of the different structures are systematically elaborated. Finally, future perspectives of microstructures for capacitive sensors are discussed, with the aim of providing a guide for designing advanced flexible and stretchable capacitive sensors via ingenious human-made microstructures.

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Chrysanthemum is widely used as a type of edible flower and also considered as the important materials of many beverages in China. Due to the occurrence of diseases and pests, and the lack of regulations for species, frequency, dose of pesticides in Chrysanthemum, pesticides have become one of the main pollutants in Chrysanthemum. The pesticide residues in Chrysanthemum were detected frequently and worth noting. This paper focused on the types of pesticides, pesticide residue detection techniques, and risk assessment methods for Chrysanthemums on the basis of relevant literatures. The pesticide residues of traditional Chinese medicine are mainly organochlorines, organophosphorus and pyrethroids, and the detection techniques include gas chromatography(GC), liquid chromatography(LC) or both combined with mass spectrometry(MS). With the increasing use of traditional Chinese medicine, Chrysanthemum is widely circulated in the market. Therefore, it is important to understand the current situation of pesticide residues in different varieties of Chrysanthemum, so as to provide theoretical reference for the control of quality and safety of Chrysanthemum and the formulation of the maximum residue limit.

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Similar to sampling perfection with application-optimized contrast using different flip angle evolutions (SPACE), T2-weighted fast field echo (FFE) also has a black blood effect and a high imaging efficiency. The purpose of this study was to optimize 3D_T2_FFE and compare it with 3D_T2_SPACE for carotid imaging. The scanning parameter of 3D_T2_FFE was optimized for the imaging of the carotid wall. Twenty healthy volunteers and 10 patients with carotid plaque underwent cervical 3D_T2_FFE and 3D_T2_SPACE examinations. The signal-to-noise ratios of the carotid wall (SNRwall) and lumen (SNRlumen), and the contrast-to-noise ratios between the wall and lumen (CNRwall_lumen) were compared. The incidence of the residual flow signal at the carotid bifurcation and the grades of flow voids in the cerebellopontine angle region in the two sequences were also compared. The reproducibility of the two sequences was tested. No significant difference was observed between the two sequences in terms of the SNRwall of healthy individuals and patients (P = 0.132 and 0.102, respectively). The SNRlumen in the 3D_T2_FFE images was lower than that in the 3D_T2_SPACE images. No significant difference was observed between the two sequences in terms of the CNRwall-lumen. The incidence of the residual flow signal at the carotid bifurcation in 3D_T2_FFE was significantly lower than that in 3D_T2_SPACE. The grades of flow suppression in the cerebellopontine angle region in 3D_T2_SPACE was lower than that in 3D_T2_FFE. Both sequences showed excellent inter-and intra-observer reproducibility. Compared to 3D_T2_SPACE, 3D_T2_FFE showed stronger flow suppression while maintaining good imaging quality, which can be used as an alternative tool for carotid imaging.

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BACKGROUND: Patients with large vessel occlusion and noncontrast computed tomography (CT) Alberta Stroke Program Early CT Score (ASPECTS) <6 may benefit from endovascular treatment (EVT). There is uncertainty about who will benefit from it. OBJECTIVE: To explore the predicting factors for good outcome in patients with ASPECTS <6 treated with EVT. METHODS: We retrospectively reviewed 60 patients with ASPECTS <6 treated with EVT in our center between March 2018 and June 2019. Patients were divided into 2 groups because of the modified Rankin Score (mRS) at 90 d: good outcome group (mRS 0-2) and poor outcome group (mRS ≥3). Baseline and procedural characteristics were collected for unilateral variate and multivariate regression analyses to explore the influent variates for good outcome. RESULTS: Good outcome (mRS 0-2) was achieved in 24 (40%) patients after EVT and mortality was 20% for 90 d. Compared with the poor outcome group, higher baseline cortical ASPECTS (c-ASPECTS), lower intracranial hemorrhage, and malignant brain edema after thrombectomy were noted in the good outcome group (all P < .01). Multivariate logistic regression showed that only baseline c-ASPECTS (≥3) was positive factor for good outcome (odds ratio = 4.29; 95% CI, 1.21-15.20; P = .024). The receiver operating characteristics curve indicated a moderate value of c-ASPECTS for predicting good outcome, with the area under receiver operating characteristics curve 0.70 (95% CI, 0.56-0.83; P = .011). CONCLUSION: Higher baseline c-ASPECTS was a predictor for good clinical outcome in patients with ASPECTS <6 treated with EVT, which could be helpful to treatment decision.

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BACKGROUND: High temperatures, particularly at night, decrease rice yield and quality. As high nighttime temperatures (HNTs) become increasingly frequent due to climate change, it is imperative to develop rice crops that tolerate HNTs. DNA methylation may represent a potential avenue for HNT-tolerant rice strain development, as this mechanism regulates gene activity and cellular phenotype in response to adverse environmental conditions without changing the nucleotide sequence. RESULTS: After HNT exposure, the methylation patterns of cytosines in the CHH context differed noticeably between two coisogenic rice strains with significantly different levels in heat tolerance. Methylation differences between strains were primarily observed on successive cytosines in the promoter or downstream regions of transcription factors and transposon elements. In contrast to the heat-sensitive rice strain, the regions 358-359 bp and 2-60 bp downstream of two basal transcriptional factors (TFIID subunit 11 and mediator of RNA polymerase II transcription subunit 31, respectively) were fully demethylated in the heat-tolerant strain after HNT exposure. In the heat-tolerant strain, HNTs reversed the methylation patterns of successive cytosines in the promoter regions of various genes involved in abscisic acid (ABA)-related reactive oxygen species (ROS) equilibrium pathways, including the pentatricopeptide repeat domain gene PPR (LOC_Os07g28900) and the homeobox domain gene homeobox (LOC_Os01g19694). Indeed, PRR expression was inhibited in heat-sensitive rice strains, and the methylation rates of the cytosines in the promoter region of PRR were greater in heat-sensitive strains as compared to heat-tolerant strains. CONCLUSIONS: After HNT exposure, cytosines in the CHH context were more likely than cytosines in other contexts to be methylated differently between the heat-sensitive and heat-tolerant rice strains. Methylation in the promoter regions of the genes associated with ABA-related oxidation and ROS scavenging improved heat tolerance in rice. Our results help to clarify the molecular mechanisms underlying rice heat tolerance.

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The effects of the growing periods, processing methods, nutritive organs and cut parts of the herbs on the quality of Andrographis Herba have been studied, which could provide scientific basis for producing high-quality crude materials of Andrographis Herba. A quantitative analysis of multi-components by single-marker(QAMS) method was used to simultaneously determine 4 diterpene lactones of andrographolide(AD), neoandrographolide(NAD), 14-deoxyandrographolide(14-DAD), and dehydroandrographolide(DHAD) in 78 batches of Andrographis Herba samples. Visual analysis, clustering analysis and partial least squares discrimination analysis(PLS-DA) were used for data processing and mining. The growing periods of Andrographis Herba were divide into the rapid growing stage(Ⅰ), the luxuriant foliage stage(Ⅱ), the bud stage(Ⅲ), the flower stage(Ⅳ), the fruiting stage(Ⅴ) and the later fruiting stage(Ⅵ), six ones in total. The results showed that the total contents of 4 diterpene lactones(TC) kept almost constant in growing periods of Ⅰ-Ⅲ, began to fall off in growing period Ⅳ, decreased rapidly in growing period Ⅴ and reduced to minimum in growing period Ⅵ. Therefore, the best harvesting period for Andrographis Herba was the bud stage. For the processing methods, none significant difference occurred for TC between drying by the sun and drying in the shade. However, in comparison of the samples dried by the sun, the samples dried in the shade exhibited lower content of AD, nonetheless, the higher contents of DHAD and NAD, indicating that the process of drying in the shade may lead to the decomposition and transformation of AD. Therefore, when the weather conditions permitted, the method drying by the sun should be used. The distributions of AD, DHAD and TC in the different cut parts and nutritive organs were determined as follows: upper cut parts > middle cut parts ≈ entire herbs > lower cut parts, leaves > entire herbs > stems. Furthermore, the contents of 4 diterpene lactones in leaves and herbs were much higher than those in stems. Therefore, it was suggested that the upper and middle cut parts of the herbs or the parts containing leaves should be preferred for harvesting to ensure the proportion of the leaves in Andrographis Herba.

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Taking Lonicerae Japonicae Flos as an example, the method of "expert consensus of different regions" was used to screen the representative samples and evaluate their commodity grades. The correlation analysis, hierarchical cluster analysis and partial least squares discriminant analysis(PLS-DA) of "commodity grade-appearance characteristic-component content" were carried out to reveal the scientificity of traditional commodity grade of Chinese medicinal material. By referring to the existing literature and the grade investigation from the sample collection regions, 78 "initial grade" samples were screened out from 118 collected samples. Authoritative experts from four regions(n=4) including Linyi(Shangdong province), Bozhou(Anhui province), Anguo(Hebei province) and Beijing were organized to evaluate their commodity grades, separately. Based on the grade consistency rate(R_i≥70%), 69 "local grade" samples were screened out from the "initial grade" samples. Based on the average grade consistency rate ■ "authoritative grade" samples were screened out from the "local grade" samples, including15 first-grade samples, 9 second-grade samples, 11 third-grade samples and 17 fourth-grade samples. For these "authoritative grade" samples, the main appea-rance characteristics were quantified and the contents of 13 components were determined by ultra performance liquid chromatography(UPLC). Furthermore, the total contents of 6 phenolic acids, 4 flavonoids and 3 iridoids were calculated, respectively. The results of correlation analysis showed that 4 appearance characteristics indices were correlated with the commodity grades: color, rate of yellow bars(including blooming flowers), rate of black heads(including black bars), and rate of stems and leaves(including bud debris). Five component content indices were correlated with the commodity grades: chlorogenic acid, isochlorogenic acid C, sweroside, loganin and the total contents of six phenolic acids. Furthermore, chlorogenic acid, loganin and the total contents of six phenolic acids showed significantly negative correlation with the main appearance characteristics, indicating that the appearance characteristics of Lonicerae Japonicae Flos can reflect its internal quality, and these 3 indices can be used as quality markers(Q-markers). The results of hierarchical cluster analysis showed that the samples of four grades were classified into four categories, and the samples with the same grades and the same categories accounted for 80.8% of the total samples, while the samples with the different grades were obviously classified into different categories. The results of PLS-DA analysis showed that the samples of different grades showed obvious intragroup aggregation and intergroup dispersion. The above results indicated that it was feasible to evaluate the traditional commodity grade of Lonicerae Japonicae Flos by the method of "expert consensus of different regions". For the evaluation of traditional commodity grade of Chinese medicinal material, the samples should be representative, expert conclusions should have enough consensuses, and grade determination should be authoritative. As the crystallization of clinical experience, traditional commodity grade can scientifically reflect the internal quality of Chinese medicinal material.

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PURPOSE: Data on posterior circulation tandem occlusions in acute ischemic stroke are scarce: recognition may be challenging and little is known about optimal treatment strategy. We report our endovascular treatment strategy for posterior circulation tandem occlusion. METHODS: Consecutive patients with posterior circulation tandem occlusions in our centre were enrolled retrospectively. The preferred strategy was "distal-to-proximal" strategy, which means opening the distal occlusion first followed by treatment of the proximal pathology. The imaging characteristics, treatment strategy, clinical outcomes, and complications of patients with posterior circulation tandem occlusions were analyzed. RESULTS: In total, 21 patients with posterior circulation tandem occlusions were enrolled in the study, which accounted for 23.6% of patients with posterior circulation stroke in our centre. The mean age was 60 years (range 32 to 80), and median pre-procedure NIHSS score was 28 (interquartile range: 13-31). Eighteen patients (85.7%) had vertebrobasilar artery tandem occlusions and 3 (14.3%) had basilar artery to basilar artery tandem occlusions. All distal occlusions were successfully recanalized (modified TICI 2b/3). Two (9.5%) of the proximal lesions were not treated. A total of 57.1% of the patients had stents implanted on the proximal occlusions. The rate of mRS 0-3 at 3 months was 57.1% and the mortality rate was 19.0%. CONCLUSION: In patients with acute ischaemic stroke caused by posterior circulation tandem occlusions, we favor "distal-to-proximal" strategy based on the positive results in this small series. Nevertheless, a more extensive study is required to explore the optimal treatment strategy further.

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