[Establishment of quality control model for high performance liquid chromatography fingerprint based on ultraviolet full-wavelength scanning spectrum: case study on different grades of Scrophulariae Radix].

High performance liquid chromatography-ultraviolet(HPLC-UV) fingerprint is one of the most important methods for the quality control of Chinese medicines in Chinese Pharmacopoeia. However, certain subjectivity is present in selection of specific band of UV, and the inherent quality differences of Chinese medicine can't be well characterized by this method. Therefore, with different grades of Scrophulariae Radix were taken as the research object in this study, a new quality control model of HPLC-UV was established in this study based on the ultraviolet full-wavelength scanning spectrum. Firstly, different grades of Scrophulariae Radix samples were collected, and the full-wavelength ultraviolet absorption spectra of all the samples were established at the bands of 200-400 nm. In order to analyze the differences among samples, the analysis model was built following multivariate statistical analysis methods such as principal component analysis(PCA) and partial least squares discrimination analysis(PLS-DA) after the pretreatment of spectral data. The result showed that the ultraviolet band at 251 nm may contribute most to distinguish the quality differences among different grades of samples. Then, the HPLC fingerprints of samples were established with the band at 251 nm. The multivariate statistical analysis showed that there was a more significant classification trend in HPLC fingerprints than that in the original UV fingerprints, which could be used to distinguish different grades of samples, and could better reflect the differences among different grades. The method reported in this study can be of a great guidance and reference for the establishment of specific fingerprints of Chinese medicines as well as for the quality control of Chinese medicine.

[Mechanism of Fuke Qianjin Capsules in treating intrauterine adhesion in rats through TGF-ß1-PI3K/Akt signaling pathway].

To explore the effect of Fuke Qianjin Capsules on anti-endometrial fibrosis in intrauterine adhesion(IUA) rats through TGF-ß1-PI3 K/Akt signaling pathway. With female SD rats as the object, IUA rat models were established through mechanical injury and infection, and they were randomly divided into normal group, sham operation group, Bujiale group(0.63 mg·kg~(-1)·d~(-1)), and high-dose Fuke Qianjin Capsules group(1.008 g·kg~(-1)·d~(-1)), medium-dose Fuke Qianjin Capsules group(0.504 g·kg~(-1)·d~(-1)), low-dose Fuke Qianjin Capsules group(0.252 g·kg~(-1)·d~(-1)). The rats were sacrificed 21 days after drug administration, and the uterus and liver were removed after blood collection from the abdominal aorta. The morphology of the uterus was observed with the naked eyes; the pathological and morphological changes of the uterine tissue and liver were observed by HE staining; the degree of fibrosis of the uterine tissue was observed by Masson staining; the expressions of TGF-ß1, TNF-α and IL-6 in serum were detected; the expressions of TGF-ß1, PI3 K, Akt, p-Akt protein in uterine tissue were detected by Western blot. The results showed that Fuke Qianjin Capsules could improve the pathological changes of uterine tissues in IUA rats, without damage to liver tissues, and reduce the expressions of TGF-ß1, TNF-α and IL-6 in serum(P<0.01); significantly reduce TGF-ß1, PI3 K, p-Akt protein expression in uterine tissues(P<0.05, P<0.01). It is indicated that Fuke Qianjin Capsules could exert the anti-endometrial fibrosis effect by regulating the TGF-ß1-PI3 K/Akt signal pathway, so as to achieve the effect in treating IUA rats, especially with the best effect in medium-dose Fuke Qianjin Capsules group.

DNA methylation of skeletal muscle function-related secretary factors identifies FGF2 as a potential biomarker for sarcopenia.

BACKGROUND: Sarcopenia is characterized by progressive loss of muscle mass and function due to aging. DNA methylation has been identified to play important roles in the dysfunction of skeletal muscle. The aim of our present study was to explore the whole blood sample-based methylation changes of skeletal muscle function-related factors in patients with sarcopenia. METHODS: The overall DNA methylation levels were analysed by using MethlTarget™ DNA Methylation Analysis platform in a discovery set consistent of 50 sarcopenic older adults (aged ≥65 years) and 50 age- and sex-matched non-sarcopenic individuals. The candidate differentially methylated regions (DMRs) were further validated by Methylation-specific PCR (MSP) in another two independent larger sets and confirmed by pyrosequencing. Receiver operating characteristic (ROC) curve analysis was used to determine the optimum cut-off levels of fibroblast growth factor 2 (FGF2)_30 methylation best predicting sarcopenia and area under the ROC curve (AUC) was measured. The correlation between candidate DMRs and the risk of sarcopenia was investigated by univariate analysis and multivariate logistic regression analysis. RESULTS: Among 1149 cytosine-phosphate-guanine (CpG) sites of 27 skeletal muscle function-related secretary factors, 17 differentially methylated CpG sites and 7 differentially methylated regions (DMRs) were detected between patients with sarcopenia and control subjects in the discovery set. Further methylation-specific PCR identified that methylation of fibroblast growth factor 2 (FGF2)_30 was lower in patients with sarcopenia and the level was decreased as the severity of sarcopenia increased, which was confirmed by pyrosequencing. Correlation analysis demonstrated that the methylation level of FGF2_30 was positively correlated to ASMI (r = 0.372, P < 0.001), grip strength (r = 0.334, P < 0.001), and gait speed (r = 0.411, P < 0.001). ROC curve analysis indicated that the optimal cut-off value of FGF2_30 methylation level that predicted sarcopenia was 0.15 with a sensitivity of 84.6% and a specificity of 70.1% (AUC = 0.807, 95% CI = 0.756-0.858, P < 0.001). Multivariate logistic regression analyses showed that lower FGF2_30 methylation level (<0.15) was significantly associated with increased risk of sarcopenia even after adjustment for potential confounders including age, sex, and BMI (adjusted OR = 9.223, 95% CI: 6.614-12.861, P < 0.001). CONCLUSIONS: Our results suggest that lower FGF2_30 methylation is correlated with the risk and severity of sarcopenia in the older adults, indicating that FGF2 methylation serve as a surrogate biomarker for the screening and evaluation of sarcopenia.

Variation of carbon source and sink along the environmental gradient from lakeside to highlands in Yuanchi swamp wetlands, Changbai Mountains, China.

Lacustrine wetlands have long-term carbon storage capacity and contribute significantly to regional carbon cycle, but it is unclear how its carbon sinks respond to climate change. We measured soil heterotrophic respiration carbon emissions (CO2 and CH4), vegetation carbon sequestration, and related environmental factors (temperature, water level, etc.) of five kinds of natural swamps (Phragmites marsh-L, Carex schmidtii marsh-C, Rhododendron capitatum swamp-D, Betula fruticose swamp-H, Larix olgensis swamp-LT)by using static chamber gas chromatography and relative growth equation methods, along the water environmental gradients from lakeside to highlands in Yuanchi of Changbai Mountains. We quantified the carbon source/sink function (CSS) and global warming potential (GWP) of various swamp types by estimating ecosystem net carbon balance, and revealed the variation patterns and formation mechanisms of CSS and GWP along the environmental gradients, aiming to explore the response of carbon source/sink of lakeside wetland in high altitude area to climate change. The results showed that marshes (L and C) were weak sources (-1.018 and -0.090 t C·hm-1·a-1) at the lower habitats of the water environment gradient, shrub swamps (D and H) were strong or weak sinks (1.956 and 0.239 t C·hm-1·a-1) at the middle habitats, forest swamp (LT) was strong source (-3.214 t C·hm-1·a-1) at the upper habitat. The spatial changes were promoted by water level and suppressed by soil temperature. For GWP, strong thermal radiation for marshes (from 44.682 to 59.282 t CO2·hm-1·a-1), cold radiation for shrub swamps (from -0.920 to -7.008 t CO2·hm-1·a-1), and weak thermal radiation for forest swamp (11.668 t CO2·hm-1·a-1), and their GWP was only promoted by soil temperature. Under current climate change background, marshes and forest swamp at both ends of the water environment gradient from lakeside to highlands played a positive feedback effect due to the increases of CH4 or CO2 emissions, while the middle shrub swamp still maintained a negative feedback effect in Yuanchi located the high-altitude area of the temperate Changbai Mountains.

[Spatial differentiation and mechanism of carbon source/sink of forest swamps in riverside of Changbai Mountains, China]. / 长白山河滨森林湿地碳源/汇空间分异规律及机制.

To quantify the carbon source/sink function of riparian zone swamps and explore the feedback relationship with climate change, we measured the annual fluxes of soil greenhouse gas, soil carbon emission, net vegetation carbon sequestration and related environmental factors (temperature, water level, etc.) by static chamber-gas chromatography and relative growth equation methods in three kinds of forest swamps (Alnus sibirica swamp, Betula platyphylla swamp, and Larix olgensis swamp) distributed along the water reduction gradient of lowland to highland in the stream riparian zone of Changbai Mountains. The results showed that the annual fluxes of CH4(0.19-0.85 mg·m-2·h-1), CO2(60.81-228.63 mg·m-2·h-1), and N2O (-0.02-0.05 mg·m-2·h-1) showed spatial variations along the water gradient of lowland to highland, with a trend of first constant then decreasing, decreasing, and first absorption then emission, respectively. The spatial variations of annual fluxes of these greenhouse gases were controlled by water levels. The annual net carbon sequestration of vegetation (2.61-3.45 t C·hm-2·a-1) was constant along the water gradient, which was mainly promoted by nitrate nitrogen content. The carbon source/sink and global warming potential (GWP) undergo regular changes along water gradients. The A. sibirica swamp was a carbon sink (1.93 t C·hm-2·a-1), the B. platyphylla swamp was a weak carbon source (-0.18 t C·hm-2·a-1), and the L. olgensis swamp was a strong carbon source (-2.51 t C·hm-2·a-1). The spatial variation of carbon source/sink in forest swamps was jointly promoted by water level and nitrate nitrogen content. A. sibirica swamp exhibited a strong cooling effect with a strong negative feedback effect on climate change (-5.88 t CO2·hm-2·a-1). L. olgensis swamp exhibited a strong warming effect with a strong positive feedback effect (10.97 t CO2·hm-2·a-1). B. platyphylla swamp exhibited a weak warming effect, approximately neutral (2.95 t CO2·hm-2·a-1). The spatial variation of GWP in forest swamps was mainly inhibited by water level.

Serum Retinol Binding Protein 4 as a Potential Biomarker for Sarcopenia in Older Adults.

Sarcopenia is characterized by progressive loss of muscle mass and function due to aging. Retinol-binding protein 4 (RBP4) is an adipokine with pro-inflammatory effects. However, the change of RBP4 concentration and its role in sarcopenia remains unclear. The aim of this study was to evaluate the association of serum RBP4 level with sarcopenia in the older adults. A total of 816 community-dwelling older adults aged ≥60 years were enrolled. Serum RBP4 was measured by enzyme-linked immunosorbent assay. Appendicular skeletal muscle mass index (ASMI), grip strength, and gait speed were measured. We found that serum RBP4 levels were higher in patients with sarcopenia when compared with those without sarcopenias (44.3 [33.9-57.7] vs 38.0 [28.0-48.4] µg/mL). Receiver operating characteristic curve analysis indicated that the optimal cutoff value of serum RBP4 level that predicted sarcopenia was 38.79 µg/mL with a sensitivity of 67.8% and a specificity of 53.3%. Multivariate logistic regression analysis showed that the subjects with a higher level of RBP4 had a higher risk of sarcopenia (adjusted odds ratio [OR] = 2.036, 95% CI = 1.449-2.861). Serum RBP4 concentration was negatively correlated with grip strength (r = -.098), gait speed (r = -.186), and AMSI (r = -.096). Moreover, serum RBP4 levels were higher in patients with severe sarcopenia when compared with those with moderate sarcopenia (49.0 [37.3-61.2] vs 40.4 [31.3-51.2] µg/mL). Taken together, our results demonstrate that serum RBP4 level is correlated with the risk and severity of sarcopenia in the older adults, indicating that RBP4 might serve as a surrogate biomarker for the screening and evaluation of sarcopenia.

[Effects of nitrogen management on soil microbial community structure at different growth stages under straw returning in paddy soils]. / 秸秆还田下氮肥运筹对水稻各生育期土壤微生物群落结构的影响.

Effects of different nitrogen application methods on microbial community structure of paddy soil at different rice growth stages were examined using phospholipid fatty acid analysis (PLFA) and Biolog technique. There were four treatments, no straw returning or fertilization (CK), straw returning +urea with the proportions of after wheat harvest, before rice transplanting, tillering stage and booting stage being 0:6:2:2 (T1) and 3:3:2:2 (T2), and straw returning+co-application of biogas slurry and urea with the proportion of after wheat harvest, before rice transplanting, tillering stage and booting stage being 3 (biogas slurry):3 (2biogas slurry+1urea):2 (urea):2 (urea)(T3). Results showed that T3 significantly increased soil available nitrogen contents at all growth stages, which was significantly higher at maturity stage than that at tillering and booting stages. T1-T3 had higher available phosphorus and available potassium contents at all growth stages compared with CK, which were higher at tillering stage than at booting and maturity stages. The interaction between growth stage and treatment in paddy soil significantly affected the contents of soil available nitrogen, available phosphorus and available potassium. Furthermore, carbohydrate, amino acid, polymer and carboxylic acid were the primary carbon sources for microbial community of paddy soil. T3 effectively enhanced soil carbon sources metabolic utilization intensity. The interaction between growth stage and treatment in paddy soil significantly affected the microbial utilization capacity of carbohydrates and carboxylic acids. Soil microbial biomass was significantly higher in T2 and T3 treatments. Moreover, T2 had high fungi/bacteria (F/B) value, indicating that fungi could benefit the stabilization of paddy soil. In summary, simultaneous nitrogen application (urea or biogas slurry) and straw returning could increase soil microbial activity and improve soil environment in paddy field.

A micro-computed tomographic evaluation of dentinal microcrack alterations during root canal preparation using single-file Ni-Ti systems.

The aim of the present study was to evaluate the length of dentinal microcracks observed prior to and following root canal preparation with different single-file nickel-titanium (Ni-Ti) systems using micro-computed tomography (micro-CT) analysis. A total of 80 mesial roots of mandibular first molars presenting with type II Vertucci canal configurations were scanned at an isotropic resolution of 7.4 µm. The samples were randomly assigned into four groups (n=20 per group) according to the system used for root canal preparation, including the WaveOne (WO), OneShape (OS), Reciproc (RE) and control groups. A second micro-CT scan was conducted after the root canals were prepared with size 25 instruments. Pre- and postoperative cross-section images of the roots (n=237,760) were then screened to identify the lengths of the microcracks. The results indicated that the microcrack lengths were notably increased following root canal preparation (P<0.05). The alterations in microcrack length in the OS group were more significant compared with those in the WO, RE and control groups (P<0.05). In conclusion, the formation and development of dentinal microcracks may be associated with the movement caused by preparation rather than the taper of the files. Among the single-file Ni-Ti systems, WO and RE were not observed to cause notable microcracks, while the OS system resulted in evident microcracks.

Genome-Wide Screening for Novel Candidate Virulence Related Response Regulator Genes in Xanthomonas oryzae pv. oryzicola.

Two-component regulatory system (TCS), a major type of cellular signal transduction system, is widely used by bacteria to adapt to different conditions and to colonize certain ecological niches in response to environmental stimuli. TCSs are of distinct functional diversity, genetic diversity, and species specificity (pathovar specificity, even strain specificity) across bacterial groups. Although TCSs have been demonstrated to be crucial to the virulence of Xanthomonas, only a few researches have been reported about the studies of TCSs in Xanthomonas oryzae pathovar oryzicola (hereafter Xoc), the pathogen of rice bacterial streak disease. In the genome of Xoc strain GX01, it has been annotated 110 TCSs genes encoding 54 response regulators (RRs), 36 orthodox histidine kinase (HKs) and 20 hybrid histidine kinase (HyHKs). To evaluate the involvement of TCSs in the stress adaptation and virulence of Xoc, we mutated 50 annotated RR genes in Xoc GX01 by homologous vector integration mutagenesis and assessed their phenotypes in given conditions and tested their virulence on host rice. 17 RR genes were identified to be likely involved in virulence of Xoc, of which 10 RR genes are novel virulence genes in Xanthomonas, including three novel virulence genes for bacteria. Of the novel candidate virulence genes, some of which may be involved in the general stress adaptation, exopolysaccharide production, extracellular protease secretion and swarming motility of Xoc. Our results will facilitate further studies on revealing the biological functions of TCS genes in this phytopathogenic bacterium.

Design, synthesis and structural exploration of novel fluorinated dabigatran derivatives as direct thrombin inhibitors.

Twenty-one fluorinated dabigatran derivatives were designed based on the bioisosteric principle. All derivatives were synthesised and evaluated for their thrombin inhibitory activity in vitro. Among these compounds, 14h, 14m, 14s and 14t were potent and the activity was in the range of reference drug, dabigatran. Three structural changes were introduced in these 21 compounds to elucidate the structure-activity relationship of the drugs. In addition, prodrugs of compounds 14h and 14s were developed to investigate their anticoagulant activities in vivo. In these experiments, compound 16 showed a fairly strong inhibitory effect on thrombin-induced platelet aggregation, and demonstrated potent activity for inhibiting arteriovenous thrombosis with an inhibition rate of (73 ± 6) %, which was comparable to that of dabigatran etexilate (76 ± 2) %. Moreover, molecular docking studies were performed to understand the binding interactions of active compounds 14h, 14s and 14t with thrombin protein (PDB ID:1KTS). Contour maps obtained from the 3D-QSAR model are meaningful in designing more active molecules to act as direct inhibitors of thrombin.

Reduction of fibrosis in dibutyltin dichloride-induced chronic pancreatitis using rat umbilical mesenchymal stem cells from Wharton's jelly.

OBJECTIVES: The objective of this study was to investigate the effects of rat umbilical cord mesenchymal stem cells (UCMSCs) from Wharton's jelly on dibutyltin dichloride (DBTC)-induced chronic pancreatitis (CP) and subsequent pancreatic fibrosis in rats. METHODS: A rat model of CP induced by DBTC was used. Male Sprague-Dawley rats were randomly divided into 4 groups: the control, DBTC, DBTC + UCMSCs, and control + UCMSC groups. Umbilical cord mesenchymal stem cells were administered intravenously on day 5 after the administration of DBTC. On days 14 and 28, the rats were evaluated morphologically and biochemically. The expression levels of inflammatory cytokines and chemokines in the pancreatic tissues of different groups were evaluated using quantitative real-time polymerase chain reaction. The activation of pancreatic stellate cells was estimated by immunochemistry and Western blot analysis of α-smooth muscle actin. RESULTS: Umbilical cord mesenchymal stem cells were detected in inflamed pancreatic tissues. Umbilical cord mesenchymal stem cell treatment improved the histological scores and alleviated the fibrosis of pancreas samples, The expression of cytokines in the DBTC + UCMSC group was significantly lower than that in the DBTC group. Also, pancreatic stellate cell activation was inhibited by UCMSC treatment. CONCLUSIONS: Xenogeneic transplantation of UCMSCs is a novel approach for the treatment of CP and subsequent fibrosis. Umbilical cord mesenchymal stem cells may be a promising therapeutic intervention for human CP in the future.