Impacts of spectral characteristics of dissolved organic matter on methylmercury contents in peatlands, Northeast China.

Dissolved organic matter (DOM) plays an important role in promoting or suppressing methylmercury (MeHg) production in wetlands. However, the effects of DOM spectral characteristics on MeHg levels remain poorly understood in boreal peatlands in Northeast China, where is undergoing remarkable climate warming. In the present work, soil samples were collected from 22 peatlands in the Greater Khingan Mountains (GKM) to test the hypothesis that DOM spectral properties control MeHg levels. DOM was characterized by UV-Vis absorption and fluorescence spectroscopy; the three-dimensional fluorescence excitation-emission matrix (EEM) was used to unveil the origin of DOM. The average total mercury (THg) and MeHg contents were 112.76 µg/kg and 12.43 µg/kg across all peatlands, respectively. There was a significantly positive correlation between MeHg and the longitude spanning the range from 120 to 123°E (p < 0.05). Proportions of MeHg to THg (%MeHg), 12.3% on average, were positively correlated with DOM humification degree at p < 0.05 level. Protein-like components of DOM (P-like) were negatively related to %MeHg. DOM had positive effects on THg, and P-like components, HIX and BIX can negatively affect THg as well as MeHg. Our findings demonstrate that the spectral characteristics of DOM in soil are crucial to the content of methyl mercury in the GKM soil.

Accumulation of mercury in the terrestrial food chain of the Liaohe estuary wetlands, China.

Mercury is a global pollutant that can be enriched in organisms and eventually endanger human health. In this paper, we studied the soil, plants, and animals in the sandy beach, winged alkali pong wetland, reed wetland, and rice field in Liaohe estuary in 2018 and 2019, measured the plant and animal carbon and stable nitrogen isotopes, and carried out the food chain construction by animal carbon and nitrogen stable isotopes, and studied and analyzed the accumulation of mercury from the producer to the consumer of the food chain. The results showed that the food chain construction at the sampling sites was as follows: S1: plants < flesh worms, ants < spiders; S4: plants < moths, leaf beetles, mosquitoes, ants < spiders; S6: plants < mosquitoes < spiders; S7: plants < flattened hooks, mosquitoes, ants < spiders; S9: plants < ants < spiders. The range of Hg in soil: S1: 0.087-0.175 mg/kg; S2: 0.035-0.197 mg/kg; S3: 0.089-0.249 mg/kg; S4: 0.050-0.167 mg/kg; S5: 0.024-0.150 mg/kg; S6: 0.066-0.152 mg/kg. S7: 0.035-0.165 mg/kg; S8: 0.026-0.083 mg/kg; S9: 0.035-0.191 mg/kg. The range of Hg in plant samples: S1: 0.019-0.242 mg/kg; S2: 0.019-0.161 mg/kg; S3: 0.025-0.142 mg/ kg; S4: 0.010-0.120 mg/kg; S5: 0.015-0.269 mg/kg; S6: 0.040-0.079 mg/kg; S7: 0.014-0.300 mg/kg; S8: 0.020-0.100 mg/kg; S9: 0.022-0.208 mg/kg. Constructing the food chain of In animal samples, the accumulation of Hg: S1: 0.061-0.355 mg/kg; S3: 0.082-0.198 mg/kg; S4: 0.051-0.230 mg/kg; S6: 0.032-0.449 mg/kg; S7: 0.078-0.195 mg/kg; S9: 0.086-0.189 mg/kg By comparing the data, the annual accumulation of heavy metals in soil and plant samples showed an increasing trend and combined with the trophic level relationship of the food chain, it was found that the accumulation trend of heavy metals increased step by step with the trophic level of consumers.

Global dynamics of an age-dependent multiscale hepatitis C virus model.

In this paper, we focus on the global dynamics of a multiscale hepatitis C virus model. The model takes into account the evolution of the virus in cells and RNA. For the model, we establish the globally asymptotical stability of both infection-free and infected equilibria. We first give the basic reproduction number [Formula: see text] of the model, and then find that the system holds infected equilibrium when [Formula: see text]. Using eigenvalue analysis, Lyapunov functional, persistence theory and so on, it is proved that infection-free and infected equilibria are globally asymptotically stable when [Formula: see text] and [Formula: see text], respectively. Thus, extinction and persistence of viruses in cells are theoretically judged. Finally, we show our theoretical results by means of numerical simulation.

Biosynthesis of biocompatibility Ag2Se quantum dots in Saccharomyces cerevisiae and its application.

As fluorescence in the second near-infrared window (NIR-II, 1000-1400 nm) could image deep tissue with high signal-to-noise ratios compared with that in NIR-I (750-900 nm), Ag2Se quantum dots (QDs) with fluorescence in the NIR-II could be ideal fluorophores. Here, we described a biosynthesis method to prepare the Ag2Se QDs by using temporally coupling the irrelated biochemical reactions, whose photoluminescence (PL) emission can reach NIR-II. The nanoparticles were characterized by transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The results showed that the nanoparticles obtained by extracellular purification were Ag2Se QDs with a uniform size of 3.9 ± 0.6 nm. In addition, the fluorescence intensity of Saccharomyces cerevisiae was improved successfully by nearly 4-fold by constructed engineering strain. In particular, the biosynthesis of Ag2Se QDs had good biocompatibility because it was capped by protein. Furthermore, investigating the toxicity of Ag2Se on cells and NIR images of nude mice showed that the Ag2Se synthesized using S. cerevisiae had low toxicity and could be used for in vivo imaging. In this work, the synthesis pathway of biocompatible Ag2Se was broadened and laid a foundation for the enlarged applicability of bioimaging in the biosynthesis of NIR-II QDs.

Glycemic deviation index: a novel method of integrating glycemic numerical value and variability.

BACKGROUND: There are many continuous blood glucose monitoring (CGM) data-based indicators, and most of these focus on a single characteristic of abnormal blood glucose. An ideal index that integrates and evaluates multiple characteristics of blood glucose has not yet been established. METHODS: In this study, we proposed the glycemic deviation index (GDI) as a novel integrating characteristic, which mainly incorporates the assessment of the glycemic numerical value and variability. To verify its effectiveness, GDI was applied to the simulated 24 h glycemic profiles and the CGM data of type 2 diabetes (T2D) patients (n = 30). RESULTS: Evaluation of the GDI of the 24 h simulated glycemic profiles showed that the occurrence of hypoglycemia was numerically the same as hyperglycemia in increasing GDI. Meanwhile, glycemic variability was added as an independent factor. One-way ANOVA results showed that the application of GDI showed statistically significant differences in clinical glycemic parameters, average glycemic parameters, and glycemic variability parameters among the T2D groups with different glycemic levels. CONCLUSIONS: In conclusion, GDI integrates the characteristics of the numerical value and the variability in blood glucose levels and may be beneficial for the glycemic management of diabetic patients undergoing CGM treatment.

Total and Methylmercury of Suaeda heteroptera Wetland Soil Response to a Salinity Gradient Under Wetting and Drying Conditions.

Mercury (Hg) methylation could occur in freshwater ecosystems with low or high salinity. However, few studies are available about the effects of salinity change on mercury(Hg) release and methylation. In-situ experiments using Suaeda heteroptera wetland soil column from the Liaohe estuary were performed to decipher how total mercury (THg) and methylmercury (MeHg) contents change under fluctuant salinity and wet and dry soil conditions. Salinity gradients were set to 0.50% (S1), 1.00% (S2), 1.50% (S3) and 1.80% (S4), and pure deionized water was used as a blank control (CK). Wet and dry soil conditions were set to full inundation condition (WD1) and naturally dried treatment (WD2). Results indicated that the highest THg and MeHg contents were found in surface and bottom soil when water salinity treatment was CK under WD1. THg and MeHg decreased with salinity under WD1. THg contents in overlying water varied from 0.854 to 1.243 µg L-1 under WD1 treatments and increased with salinity change. When under WD2 treatment, THg contents in both soil layers gradually decreased with rising salinity. Meanwhile, MeHg contents in both soil layers reached the lowest level at CK (1.666 µg kg-1and 2.520 µg kg-1) and increased gradually with the rising salinity. By comparison, THg content of the soil was much lower in WD1 than that in WD2. Under the WD1 condition, the MeHg contents and %MeHg decreased with rising salinity and showed significantly different in different salinity treatment, however, its showed an opposite trend with rising salinity under the WD2 condition.

Effect of Testosterone Synthesis and Conversion on Serum Testosterone Levels in Obese Men.

Obesity is associated with decreased testosterone levels in males. Testosterone is synthesized by testosterone synthetic enzymes, which are stimulated by luteinizing hormone (LH). Testosterone can also be converted to estradiol via the aromatase. The objective of this study was to examine the factors related to testosterone synthesis and conversion, and to systematically evaluate the key processes that influence testosterone levels in male obesity. Three hundred and two male subjects (aged 25-45 years old) were divided according to BMI into normal weight (18.5-23.9 kg/m2), overweight (24-27.9 kg/m2), and obese (≥28 kg/m2) groups; or divided following WHR into non-abdominal obesity and abdominal obesity groups (WHR: ≥0.9). Male C57BL/6 mice were divided into normal diet (ND) and high-fat diet (HFD)-induced obesity group. Serum sex hormones and aromatase levels were measured using ELISAs. Testosterone synthetic enzymes in the testes were measured by qRT-PCR. The testosterone levels in obese men and abdominal obesity men were lower than normal men. In abdominal obesity men serum LH levels were decreased and associated with testosterone levels after multivariate regression analysis. Serum aromatase levels were increased in abdominal obesity males. In mice, compared to the ND group, the HFD group had decreased steroidogenic acute regulatory protein (StAR). However, aromatase levels in subcutaneous adipose tissue were higher in the ND group than HFD group. In conclusion, according to this study decreased testicular synthesis function and the conversion of testosterone may explain the reduction in testosterone levels in male obesity, and the decrease of testicular synthesis may change first.

A predictive model of thyroid malignancy using clinical, biochemical and sonographic parameters for patients in a multi-center setting.

BACKGROUND: Thyroid nodules are highly prevalent, but a robust, feasible method for malignancy differentiation has not yet been well documented. This study aimed to establish a practical model for thyroid nodule discrimination. METHODS: Records for 2984 patients who underwent thyroidectomy were analyzed. Clinical, laboratory, and US variables were assessed retrospectively. Multivariate logistic regression analysis was performed and a mathematical model was established for malignancy prediction. RESULTS: The results showed that the malignant group was younger and had smaller nodules than the benign group (43.5 ± 11.6 vs. 48.5 ± 11.5 y, p < 0.001; 1.96 ± 1.16 vs. 2.75 ± 1.70 cm, p < 0.001, respectively). The serum thyrotropin (TSH) level (median = 1.63 mIU/L, IQR (0.89-2.66) vs. 1.19 (0.59-2.10), p < 0.001) was higher in the malignant group than in the benign group. Patients with malignancies tested positive for anti-thyroglobulin antibody (TGAb) and anti-thyroid peroxidase antibody (TPOAb) more frequently than those with benign nodules (TGAb, 30.3% vs. 15.0%, p < 0.001; TPOAb, 25.6% vs. 18.0%, p = 0.028). The prevalence of ultrasound (US) features (irregular shape, ill-defined margin, solid structure, hypoechogenicity, microcalcifications, macrocalcifications and central intranodular flow) was significantly higher in the malignant group. Multivariate logistic regression analysis confirmed that age (OR = 0.963, 95% CI = 0.934-0.993, p = 0.017), TGAb (OR = 4.435, 95% CI = 1.902-10.345, p = 0.001), hypoechogenicity (OR = 2.830, 95% CI = 1.113-7.195, p = 0.029), microcalcifications (OR = 4.624, 95% CI = 2.008-10.646, p < 0.001), and central intranodular flow (OR = 2.155, 95% CI = 1.011-4.594, p < 0.05) were independent predictors of thyroid malignancy. A predictive model including four variables (age, TGAb, hypoechogenicity and microcalcification) showed an optimal discriminatory accuracy (area under the curve, AUC) of 0.808 (95% CI = 0.761-0.855). The best cut-off value for prediction was 0.52, achieving sensitivity and specificity of 84.6% and 76.3%, respectively. CONCLUSION: A predictive model of malignancy that combines clinical, laboratory and sonographic characteristics would aid clinicians in avoiding unnecessary procedures and making better clinical decisions.

Atherogenic index of plasma is a novel predictor of non-alcoholic fatty liver disease in obese participants: a cross-sectional study.

BACKGROUND: The atherogenic index of plasma showed to be related with some chronic disease like cardiovascular diseases and atherosclerosis. Body mass index which was commonly used in clinical practice is not an accurate index to predict non-alcoholic fatty liver disease. The aim of this study is to investigate the relationship between atherogenic index of plasma and non-alcoholic fatty liver disease in obese participants. METHODS: 538 obese subjects were included in this cross sectional study. Non-alcoholic fatty liver disease was diagnosed by B-ultrasonography after excluding participants with other liver diseases. The atherogenic index of plasma was classified into three groups: the low (< 0.11), the intermediate (0.11-0.21) and the high (> 0.21) risk. The participants were separated into groups according to their atherogenic index of plasma levels. The area under receiver operating characteristic curve of the atherogenic index of plasma for predicting non-alcoholic fatty liver disease was calculated. RESULTS: There were concordances between increased atherogenic index of plasma and significant increase in the value of body mass index, waist circumference, alanine aminotransferase, glutamyl transpeptidase and lipid profile. The atherogenic index of plasma is strongly associated with non-alcoholic fatty liver disease. Compared to the low risk group, the high risk group had a 5.37 folds risk after adjustment for covariates. Results of receiver operating characteristic curves showed that the area under the curve (95% confidence intervals) was 0.718 (0.670-0.766). CONCLUSION: These data suggest that atherogenic index of plasma might be a method which can be used in the auxiliary diagnosis of non-alcoholic fatty liver disease.

Clinical and molecular characterization of 5α-reductase type 2 deficiency due to mutations (p.Q6X, p.R246Q) in SRD5A2 gene.

Early diagnosis and optimal management for steroid 5α-reductase type 2 deficiency (5α-RD2) patients are major challenges for clinicians and mutation analysis for the 5α-reductase type 2 (SRD5A2) gene is the golden standard for the diagnosis of the disease. In silico analysis of this enzyme has not been reported due to the lack of appropriate model. Moreover, the histological and pathological changes of the gonads are largely unknown. In the present study, a 5α-RD2 patient born with abnormal external genitalia was studied and mutation analysis for SRD5A2 gene was conducted. Moreover, we constructed the homology modeling of 5α-reductase using SWISS-MODEL, followed by the molecular docking study. Furthermore, immunohistochemical staining of Ki67 for the testes tissue was conducted to investigate the potential pathological characteristics. The patient had male (46, XY) chromosomes but presented female characteristics, and the mutation analysis identified a heterozygotes mutation (p.Q6X, p.R246Q) in SRD5A2 gene. In silico analysis elucidated the potential effect of the mutation on enzyme activity. Immunohistochemical staining for the excised testes showed that 30%-50% of the germ cells were Ki67 positive, which indicated the early neoplastic potential. In conclusion, we analyzed the genotype-phenotype correlations of 5α-RD2 caused by a heterozygotes mutation (p.Q6X, p.R246Q). Importantly, we conducted the homology modeling and molecular docking for the first time, which provided a homology model for further investigations. Immunohistochemical results suggested gonadectomy or testis descent should be performed early for 5α-RD2 patient, as delayed treatment would have maintained the testes in a tumorigenic condition.

RagD regulates amino acid mediated-casein synthesis and cell proliferation via mTOR signalling in cow mammary epithelial cells.

This research paper addresses the hypothesis that RagD is a key signalling factor that regulates amino acid (AA) mediated-casein synthesis and cell proliferation in cow mammary epithelial cells (CMECs). The expression of RagD was analysed at different times during pregnancy and lactation in bovine mammary tissue from dairy cows. We showed that expression of RagD at lactation period was higher (P < 0·05) than that at pregnancy period. When CMECs were treated with methionine (Met) or lysine (Lys), expression of RagD, ß-casein (CSN2), mTOR and p-mTOR, and cell proliferation were increased. Further, when CMECs were treated to overexpress RagD, expression of CSN2, mTOR and p-mTOR, and cell proliferation were up-regulated. Furthermore, the increase in expression of CSN2, mTOR and p-mTOR, and cell proliferation in response to Met or Lys supply was inhibited by inhibiting RagD, and those effects were reversed in the overexpression model. When CMECs were treated with RagD overexpression together with mTOR inhibition or conversely with RagD inhibition together with mTOR overexpression, results showed that the increase in expression of CSN2 and cell proliferation in response to RagD overexpression was prevented by inhibiting mTOR, and those effects were reversed by overexpressing mTOR. The interaction of RagD with subunit proteins of mTORC1 was analysed, and the result showed that RagD interacted with Raptor. CMECs were treated with Raptor inhibition, and the result showed that the increase in expression of mTOR and p-mTOR in response to RagD overexpression was inhibited by inhibiting Raptor.In conclusion, our study showed that RagD is an important activation factor of mTORC1 in CMECs, activating AA-mediated casein synthesis and cell proliferation, potentially acting via Raptor.

Mercury bioaccumulation in arthropods from typical community habitats in a zinc-smelting area.

This study assessed the enrichment of mercury in the food web from the different community habitats in a zinc-smelting area of China. We used a nitrogen stable isotope technique to analyze trophic level relationships among arthropods and found that the first trophic level consisted of plants in the different community habitats, the second trophic level consisted of herbivores such as locusts and grasshoppers (primary consumers), and the third trophic level included spiders and mantes (secondary consumers). Mercury enrichment in the primary consumers was not evident, but enrichment in arthropods of the third trophic level was significant. The average of enrichment coefficients in spiders and mantes was greater than 1. The δ15N values indicated that mercury concentrations accumulated from primary producers to top carnivorous arthropods increased. In this zinc-smelting area, the biological amplification of mercury in the food web is significant. It is reasonable to assume that humans, located at the top of the food chain, are exposed to biomagnified levels of mercury.

The Effect of Aromatase on the Reproductive Function of Obese Males.

Obesity has increased dramatically worldwide, which is associated with male infertility. Androgen deficiency, impaired spermatogenesis, and erectile dysfunction are characteristics of male infertility. The balance of androgens and estrogens is essential for maintaining normal reproductive function in males. Aromatase, the rate-limiting enzyme in the conversion of androgens into estrogens, is present in various tissues. The expression of aromatase is proportional to body fat mass and causes more fat accumulation, thus forming a vicious cycle. Excessive aromatase activity in adipose tissue leads to increased conversion of androgens into estrogens, eventually results in a reduction of testosterone levels and is the underlying reason for obesity-related infertility. In the male reproductive system, all testicular somatic cells and germ cells express aromatase, except for peritubular myoid cells. The results of studies regarding the effect of aromatase in testicular somatic cells and germ cells have been contradictory. The effect of estrogens in testicular somatic cells is inhibitory, leading to reduced testosterone levels and sperm production; however, it has been observed that aromatase participates in the acquisition of sperm motility. The overall effect of estrogen modulation is an inhibition of spermatogenesis. Aromatase inhibitors are an effective therapy for obesity-associated hypogonadism because they restore normal sex hormone levels and improve semen parameters. This article systematically introduces the basic knowledge of aromatase and provides information of the current advances relating to aromatase in male reproductive function. Increasing our knowledge on the role of aromatase in male obesity could help in proposing new approaches to treat infertile men.

A treadmill exercise reactivates the signaling of the mammalian target of rapamycin (mTor) in the skeletal muscles of starved mice.

It has been well established that a starvation-induced decrease in insulin/IGF-I and serum amino acids effectively suppresses the mammalian target of rapamycin (mTor) signaling to induce autophagy, which is a major degradative cellular pathway in skeletal muscles. In this study, we investigated the systematic effects of exercise on the mTor signaling of skeletal muscles. Wild type C57BL/6J mice were starved for 24h under synchronous autophagy induction conditions. Under these conditions, endogenous LC3-II increased, while both S6-kinse and S6 ribosomal protein were dephosphorylated in the skeletal muscles, which indicated mTor inactivation. Using GFP-LC3 transgenic mice, it was also confirmed that fluorescent GFP-LC3 dots in the skeletal muscles increased, including soleus, plantaris, and gastrocnemius, which clearly showed autophagosomal induction. These starved mice were then subjected to a single bout of running on a treadmill (12m/min, 2h, with a lean of 10 degrees). Surprisingly, biochemical analyses revealed that the exercise elicited a decrease in the LC3-II/LC3-I ratio as well as an inversion from the dephosphorylated state to the rephosphorylated state of S6-kinase and ribosomal S6 in these skeletal muscles. Consistently, the GFP-LC3 dots of the skeletal muscles were diminished immediately after the exercise. These results indicated that exercise suppressed starvation-induced autophagy through a reactivation of mTor signaling in the skeletal muscles of these starved mice.

Adipose tissue hypoxia and low-grade inflammation: a possible mechanism for ethanol-related glucose intolerance?

The exact mechanism of ethanol's effects on glucose tolerance has not been well determined. The present study focuses for the first time on hypoxia and low-grade inflammation in adipose tissue (AT). In the in vivo experiments, twenty-four male Wistar rats were randomly allocated into control and ethanol feeding groups. Ethanol-treated rats received edible ethanol once a day at a total dosage of 5 g/kg per d, and the controls received distilled water. Ethanol volumes were adjusted every week. At the end of 8 weeks, we carried out an oral glucose tolerance test. Blood and AT were collected for measuring hypoxia-inducible factor-1α (HIF-1α), GLUT1, TNF-α, IL-6, leptin and vascular endothelial growth factor (VEGF). In the in vitro experiments, differentiated OP9 adipocytes were incubated with 100 mm of ethanol for 48 h; the media and cells were then collected for measuring HIF-1α, GLUT1, TNF-α and IL-6. The results showed that long-term ethanol consumption impaired glucose tolerance in rats. Ethanol consumption had little influence on body weight, but both epididymal and perirenal AT were markedly enlarged in the ethanol-treated rats as compared to the controls. Visceral adipose tissue (VAT) had accumulated, and the protein levels of HIF-1α and GLUT1, the indicators of hypoxia in rat epididymal AT and OP9 adipocytes, were elevated. Secondary to the AT hypoxia, the levels of inflammation-related adipokines, such as TNF-α, IL-6, leptin and VEGF, were increased. Based on these findings, we conclude that VAT hypoxia and low-grade inflammation might be a new mechanism in the treatment of ethanol-related diabetes.

[Different proportion of potassium chloride and potassium sulphate application on cultivation of Panax notoginseng].

In order to make sure whether Panax notoginseng is sensitive to chloridion and guide fertilization in planting of P. notoginseng, the effects of the different proportion of potassium chloride (KCl) and potassium sulfate (K2SO4) on the yield, quality of P. notoginseng were studied. The results showed that K fertilizer significantly improved the growth of P. notoginseng and increased the biomass per plant or per pot and the content of N, P, K and the content of saponin. In cases of conditions such as potassium, and the effects of K2SO4 on increasing the petiole length, leaf size, rhizome length, root length, and content and accumulation of Ginsenoside Rg1 were better than those of KCl. While compared with K2SO4, KCl was more conducive to augmenting height, root width, the biomass of shoot, rhizome, root and the content of Ginsenoside Rb1 and Rd. There was not remarkable difference in agronomic characters, biomass and the content of N, P, K among KCl, K2SO4 and the combination of KCl and K2SO4. However, the content of saponin of the treatment with combination of KCl and K2SO4 was significant higher than that of single KCl or K2SO4 treatments. K fertilizer significantly increased yield and the content of saponins. And P. notoginseng was not sensitive to chloridion. KCl increased the yield and the content of saponins of P. notoginseng as well as K2SO4, and the combination treatment was superior to single treatment. It is recommended that the KCl should be adopted in production, to reduce the cost of potash fertilizer.

[Comparison of agronomic traits of Panax notoginseng between traditional cultivated fields and new cultivated fields].

OBJECTIVE: In order to provide scientific basis for introduction breeding and production regionalization of Panax notoginseng, the environment of producing area, agronomic traits and medicinal material output were investigated. METHOD: Using field survey sampling at harvest time, agronomic traits indicators of leaf segment, stem segment and roots segment etc. of commodity P. notoginseng, longitude and latitude, elevation, soil type, landform of producing area were measured and observed. RESULT: The P. notogiseng cultivation was expanding from traditional area like Wenshang to new areas as Honghe, Kunming, Qujing at large scale. Comparing with traditional cultivated fields, the elevation of new fields, which are red soil of moderate or low mountain slopes and gentle hills between 1 800-2 130 m, increases markedly. The agronomic traits of new cultivated fields such as plant height, stem diameter, the ground and underground biomass were better than those of traditional cultivated fields in varying degree. Furthermore, the root weight, taproot weight, taproot length and other agronomic index augmented more than 20%. Comparison among different cultivated fields showed P. notoginseng of Honghe Shiping Niujie, Kunming Shilin Guishan, Honghe Jiangshui Guanting etc. had better agronomic traits, the plant were thick and tall, the taproot and the top of reed were large, the number of root was more. Inversely, P. notoginseng of Kunming Guandu Xiaoshao, Guangxi Jingxi Lutong, Wenshang Yanshan Jiangna were thin and small. Cluster analysis showed that cultivated fields of P. notoginseng which was across clustered by traditional and new cultivated fields can be divided into three groups, including a high-yielding region insist of three new cultivated fields Honghe Shiping Niujie, Kunming Shilin Guishan, Honghe Jiangshui Guanting and one traditional cultivated field Wenshan Yanshan Jiangna. Correlation analysis indicated that the size and weight of taproot and top of reed were significantly positive correlated with plant height, stem diameter, leaf size, leaf weight and stem weight. Regression analysis pointed out that stem diameter, leaf width, leaf length/width, leaf weight were the main factors affecting the dry weight of taproot, and the main factors influencing the dry weight of top of reed were plant height, petiole, leaf length, leaf width and other agronomic traits. CONCLUSION: From agronomic traits, P. notoginseng in new cultivated fields were more robust than that in traditional fields, but besides the length of taproot, the difference of rest agronomic traits didn't reach the significant level. It is suggested that, in the west and the north of traditional area, the red soil land of moderate or low mountain slopes and gentle hills where the elevation is between 1 800-2 130 m is suitable for cultivating P. notoginseng. Honghe Shiping Niujie, Honghe Jianshui Guanting, Kuming Shilin Gongshan can be used as vital development area for commodity P. notoginseng.

Ferulic acid induces mammalian target of rapamycin inactivation in cultured mammalian cells.

Ferulic acid (FA), a naturally occurring polyphenol abundant in vegetables and rice bran, is known to possess a potent antioxidant activity, thereby protecting cells from oxidative stress. In the present study, we show that in addition to its known anti-oxidant activity, ferulic acid exerts substantial inhibitory activity on cellular mammalian target of rapamycin (mTor)-signaling pathways. In HeLa cells and mouse primary hepatocytes cultured with conventional nutrient-rich media, ferulic acid (1 mM) elicited dephosphorylation of S6 kinase and its substrate ribosomal S6. The dephosphorylating activity of ferulic acid was almost comparable to that of rapamycin, an established mTor inhibitor (TORC1). We next investigated the effect of ferulic acid on autophagy, a major cellular degradative process, which significantly contributes to the maintenance of cell homeostasis. Using a conventional green fluorescent protein-microtubule-associated protein IA/IB light chain 3 (GFP-LC3) dot assay to evaluate autophagy flux, we showed that ferulic acid caused a significant increase in GFP-LC3 dots under serum-rich conditions in HeLa cells. The enhancement of autophagic flux by ferulic acid was almost equivalent to that of rapamycin. Furthermore, ferulic acid significantly enhanced autophagic degradation of (14)C-leucine-labeled long-lived proteins of cultured mouse hepatocytes under nutrient-rich conditions, but not nutrient-deprived conditions. These results indicate that ferulic acid is almost the equivalent of rapamycin in the ability to inhibit mTor (TORC1), which makes it a potent activator of basal autophagy.

Effects of phosphorus application on yield, quality and phosphorus use efficiency of edible sweetpotato: A case study of Xushu 32.

To explore the appropriate amount of phosphorus (P) fertilizer and improve economic yield and P use efficiency of edible sweetpotato, we took Xushu 32 as an example and compared the effects of different P application rates on yield, quality, P accumulation and P use efficiency of edible sweetpotato based on a two-year field experiment (soil available P content was 31.70 mg·kg-1) from 2018 to 2019. There were five P application levels (P2O5), including 0 (P0), 25 (P25), 50 (P50), 75 (P75) and 100 kg·hm-2(P100). The results showed that, 1) compared with P0, P application significantly increased the yield of fresh sweetpotao and commodity potato, with the effects being the stongest under P75 treatment, followed by P50 treatment. However, there was no significant difference between the two treatments. 2) P application significantly increased the contents of starch and reducing sugar in storage root. The contents of soluble sugar and protein increased significantly under P50 treatment. 3) Du-ring the growth period of 90 to 120 d, P fertilizer supply significantly increased P accumulation and dry matter accumulation of sweetpotato. 4) The apparent P use efficiency (APUE) decreased with increasing P application rates, while P agronomic efficiency (PAE) increased first and then decreased with the increases of P application rates, which was significantly higher under P50 than other treatments. Taking into account the yield, quality, economic yield and P utilization rate of edible sweetpotato, the optimal dosage of P2O5 is 50 kg·hm-2 under the experimental conditions.

Label-free fluorescent detection of ions, proteins, and small molecules using structure-switching aptamers, SYBR Gold, and exonuclease I.

We have demonstrated a label-free sensing strategy employing structure-switching aptamers (SSAs), SYBR Gold, and exonuclease I to detect a broad range of targets including inorganic ions, proteins, and small molecules. This nearly universal biosensor approach is based on the observation that SSAs at binding state with their targets, which fold into secondary structures such as quadruplex structure or Y shape structure, show more resistance to nuclease digestion than SSAs at unfolded states. The amount of aptamer left after nuclease reaction is proportional to the concentrations of the targets and in turn is proportional to the fluorescence intensities from SYBR Gold that can only stain nucleic acids but not their digestion products, nucleoside monophosphates (dNMPs). Fluorescent assays employing this mechanism for the detection of potassium ion (K(+)) are sensitive, selective, and convenient. Twenty µM K(+) is readily detected even at the presence of a 500-fold excess of Na(+). Likewise, we have generalized the approach to the specific and convenient detection of proteins (thrombin) and small molecules (cocaine). The assays were then validated by detecting K(+), cocaine, and thrombin in urine and serum or cutting and masking adulterants with good agreements with the true values. Compared to other reported approaches, most limited to G-quadruplex structures, the demonstrated method has less structure requirements of both the SSAs and their complexes with targets, therefore rending its wilder applications for various targets. The detection scheme could be easily modified and extended to detection platforms to further improve the detection sensitivity or for other applications as well as being useful in high-throughput and paralleled analysis of multiple targets.