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1.
Zhongguo Zhen Jiu ; 40(5): 505-9, 2020 May 12.
Artigo em Chinês | MEDLINE | ID: mdl-32394658

RESUMO

OBJECTIVE: To observe the therapeutic effect of acupuncture on cancer-related fatigue (CRF) and to explore its possible mechanism. METHODS: A total of 80 patients with CRF were randomized into an observation group and a control group, and finally 67 patients completed the trial (36 patients in the observation group, 31 patients in the control group). Patients in the control group were treated with conventional chemoradiotherapy and symptomatic treatment, while no particular anti-fatigue intervention was adopted. On the basis of treatment in the control group, acupuncture was applied at Baihui (GV 20), Guanyuan (CV 4), Qihai (CV 6), Fengchi (GB 20), Zusanli (ST 36), Sanyinjiao (SP 6) in the observation group, once a day, 5 times as one course, with 2 days interval between each course, totally 4 courses were required. Before and after treatment, scores of functional assessment of cancer therapy-fatigue (FACT-F) in Chinese and McGill quality of life questionnaire (MQOL), serum levels of C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-α(TNF-α) and soluble TNF receptor-1 (sTNF-R1) were observed in the two groups. RESULTS: ①Compared before treatment, the FACT-F score was decreased after treatment in the observation group (P<0.05), while there was no significant difference in the control group (P<0.05). The change of the FACT-F score in the observation group was larger than that in the control group (P<0.05). ②In the observation group, scores of physiological and psychological dimension were decreased (P<0.05), score of social support dimension was increased after the treatment (P<0.05). The score changes of physiological, psychological and social support dimension in the observation group were larger than those in the control group (all P<0.05). ③After treatment, the serum levels of IL-6, TNF-α and sTNF-R1 were decreased in the observation group (P<0.05), while the serum levels of CPR and IL-6 were increased in the control group (P<0.05). The serum levels of CPR, IL-6 and TNF-α in the observation were lower than those in the control group (P<0.05). CONCLUSION: ①Acupuncture can improve the related symptoms of depression, weakness and headache in patients with CRF, strengthen their cognition of the support from society and family, and boost the confidence in curing the disease. ②Acupuncture can effectively down-regulate serum levels of the relative inflammatory factors, which may be its possible mechanism on treating CRF.

2.
Vet Parasitol ; 280: 109068, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32278937

RESUMO

Interleukin-4 (IL-4), an immunomodulatory cytokine derived from activated T lymphocytes were shown to regulate Th2-type immune responses. It plays an important role in anti-parasitic infections. In this study, a recombinant plasmid was designed using murine IL-4 co-expressed with pgsA anchor system of Lactobacillus plantarum NC8 and was delivered by live Lactobacillus plantarum NC8, which exhibited an enhanced immunogenicity in protection of BALB/c mice from infection with Trichinella spiralis. The results showed that the levels of serum IgG1 and mucosal secretory IgA (sIgA) were both increased significantly in mice orally inoculated with NC8-pSIP409-pgsA-mIL-4, and the Th2 phenotype immune response was up-regulated. A 29.9 % reduction in adult worm burden at 7 days post-infection (dpi) and 83.3 % reduction in muscle larvae burden at 28 dpi were observed in immune-stimulated mice with NC8-pSIP409-pgsA-mIL-4. Moreover, weight loss and pathological changes were also improved in mice of NC8-pSIP409-pgsA-mIL-4 group. Taken together, it suggests that NC8-pSIP409-pgsA-mIL-4 could improve the intestinal mucosal immunity and promoted the elimination of the adult worm in Trichinella-infected mice. This study laid the foundation for the development of a novel vaccines against Trichinellosis.

3.
Zhongguo Zhong Yao Za Zhi ; 45(4): 846-853, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32237485

RESUMO

To explore the relationship between the variations of the physiochemical properties of traditional Chinese medicine(TCM) decoction before or after precipitation in alcohol and the wall stickiness in spray drying. In this study, widely used TCMs in clinic were selected to determine the physiochemical properties of TCM decoction before or after precipitation in alcohol separately.Afterwards, the principle component analysis(PCA),Hierarchical cluster analysis(HCA),and orthogonal partial least squares-discriminate analysis(OPLS-DA) were used to evaluate the relationship between the variations of those liquid before or after precipitation in alcohol and hot-melt stickiness in spray drying.Three types of statistical analysis methods all indicated that ethanol precipitation affected physiochemical properties of TCM decoction, and the variations of physical properties showed significant association with hot-melt stickiness in spray drying.The results of PCA-X and HCA suggested that the dynamic surface tension(DST) was impacted most by the alcohol deposition treatment,at the same time,the other 5 physiochemical properties were also affected.OPLS-DA verified that PCA-X and HCA results, and revealed that DST,equilibrium surface tension(EST) and pH were significantly affected by alcohol deposition treatment,and the order of the affecting factors from high to low was DST,EST and pH.Therefore,the downward trend of DST and pH were the important factors that directly affected the hot-melt stickiness of TCM after precipitation in alcohol,which would be probably caused by losing macromolecules alcoholic insoluble components and increasing relative proportions of organic acid and small molecule sugar.

4.
Gene ; 747: 144657, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32298762

RESUMO

OBJECTIVE: We analysed the effect of expression of nucleolar spindle-associated protein 1 (NuSAP1) on the prognosis of breast cancer (BC) and investigated its potential mechanism of tumourigenicity in triple-negative breast cancer (TNBC) cell lines. MATERIALS AND METHODS: We downloaded the RNA-seq breast cancer (BC) data from The Cancer Genome Atlas (TCGA) and screened for the NuSAP1 gene using R software. The clinical data for patients with BC were screened and analysed using R software. A survival curve was drawn using the Kaplan-Meier Plotter. Cell proliferation and invasion were verified by the Cell Counting Kit-8 and Transwell assays. Expression of NuSAP1, the Wnt/ß-catenin pathway, and epithelial-mesenchymal-transition-related proteins in TNBC was detected using real-time quantitative polymerase chain reaction (qRT-PCR) and western blotting (WB). RESULTS: Expression of NuSAP1 was upregulated in BC. The change in NuSAP1 expression levels was associated with multiple clinicopathological factors, and the higher the expression of NuSAP1 was, the shorter the survival time. In MDA-MB-231 and BT549 cells, knockdown of NuSAP1 expression resulted in a significant decrease in cell proliferation and invasion; a decrease in expression of cyclin D1, vimentin, Slug, Twist, wnt3a, and pß-catenin; and an increase in expression of e-cadherin. The results of the sh-NuSAP1 + ov-NuSPA1 group were the opposite of the results of the sh-NuSAP1 group. CONCLUSION: NuSAP1 is a carcinogen that facilitates progression of TNBC through the Wnt/ß-catenin and epithelial-mesenchymal transition pathways.


Assuntos
Transição Epitelial-Mesenquimal , Neoplasias de Mama Triplo Negativas/patologia , Via de Sinalização Wnt , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Prognóstico , Modelos de Riscos Proporcionais , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Análise de Sobrevida , Neoplasias de Mama Triplo Negativas/genética
5.
J Am Chem Soc ; 142(18): 8109-8115, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32319766

RESUMO

We report a one-step procedure to directly reduce unactivated aryl esters into their corresponding tolyl derivatives. This is achieved by an organosilane-mediated ester hydrosilylation reaction and subsequent Ni/NHC-catalyzed hydrogenolysis. The resulting conditions provide a direct and efficient alternative to multi-step procedures for this transformation that often require the use of hazardous metal hydrides. Applications in the synthesis of -CD3-containing products, derivatization of bioactive molecules, and chemoselective reduction in the presence of other C-O bonds are demonstrated.

6.
J Econ Entomol ; 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32300789

RESUMO

Asian longhorned beetle, Anoplophora glabripennis (Motschulsky), is a high-risk invasive forest pest worldwide. We surveyed Asian longhorned beetle parasitoid guilds and their seasonal abundance using field-deployed sentinel host logs infested with Asian longhorned beetle eggs or newly hatched (early-instar) larvae in three different sites of China (Beijing City, Shanghai City, and Jilin Province) from 2015 to 2018. Our survey detected 12 species of hymenopteran parasitoids (four Pteromalidae, three Braconidae, two Eupelmidae, one Eurytomidae, one Ichneumonidae, and one Bethylidae) attacking sentinel Asian longhorned beetle larvae or eggs deployed in these sites. Total parasitism by all the parasitoid species varied with different sites and across different years of the survey (averaging 7-16% in Beijing, 4-11% in Shanghai, and 0-0.2% in Jilin Province). In addition, the seasonal pattern of parasitism also differed among different sites, with parasitism peaking in July in the northern site (Beijing, 19%) and June in the southern site (Shanghai, 16%). Among all the parasitoid species recovered, Oxysychus sp. (Hymenoptera: Pteromalidae) was the most abundant parasitoid species in both Beijing and Shanghai (with 42-66% relative abundance and an average of 6% Asian longhorned beetle parasitism). The second most abundant species was Bracon planitibiae Yang, Cao et Gould (Hymenoptera: Braconidae), which accounted for 35% of the species collected and caused an average of 5% Asian longhorned beetle parasitism. Relevance of our findings to Asian longhorned beetle biocontrol is discussed.

7.
Parasit Vectors ; 13(1): 56, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32046772

RESUMO

BACKGROUND: Eimeria spp. are responsible for chicken coccidiosis which is the most important enteric protozoan disease resulting in tremendous economic losses in the poultry industry. Understanding the interaction between the avian cecal microbiota and coccidia is of interest in the development of alternative treatments that do not rely on chemotherapeutics and do not lead to drug resistance. METHODS: We utilized 16S rRNA gene sequencing to detect the dynamics of the cecal microbial community in AA broilers challenged with Eimeria tenella. Histopathological analysis of the cecum was also conducted. RESULTS: We found that microbial shifts occur during the infection. Lactobacillus, Faecalibacterium, Ruminococcaceae UCG-013, Romboutsia and Shuttleworthia decreased in abundance. However, the opportunistic pathogens Enterococcus and Streptococcus increased in abundance over time in response to the infection. CONCLUSIONS: Eimeria tenella disrupts the integrity of the cecal microbiota and could promote the establishment and growth of potentially pathogenic bacteria. Defining bacterial populations affected by coccidial infection might help identify bacterial markers for intestinal disease as well as populations or species that could be beneficial in maintaining and restoring gut homeostasis during and after infection with E. tenella.

8.
Pest Manag Sci ; 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32077251

RESUMO

BACKGROUND: RNA interference (RNAi)-based pest management requires efficient delivery and large-batch production of double-stranded (ds)RNA. We previously developed a nanocarrier-mediated dsRNA delivery system that could penetrate an insect's body and efficiently silence gene expression. However, there is a great need to improve the plasmid-Escherichia coli system for the mass production of dsRNA. Here, for efficient dsRNA production, we removed the rnc gene encoding endoribonuclease RNase III in E. coli BL21(DE3) and matched with the RNAi expression vector containing a single T7 promoter. RESULTS: The novel pET28-BL21(DE3) RNase III-system was successfully constructed to express vestigial (vg)-dsRNA against Harmonia axyridis. dsRNA was extracted and purified from cell cultures in four E. coil systems, and the yields of dsRNA in pET28-BL21(DE3) RNase III-, pET28-HT115(DE3), L4440-BL21(DE3) RNase III- and L4440-HT115(DE3) were 4.23, 2.75, 0.88 and 1.30 µg mL-1 respectively. The dsRNA expression efficiency of our novel E. coil system was three times that of L4440-HT115(DE3), a widely used dsRNA production system. The RNAi efficiency of dsRNA produced by our system and by biochemical synthesis was comparable when injected into Harmonia axyridis. CONCLUSION: Our system expressed dsRNA more efficiently than the widely used L4440-HT115(DE3) system, and the produced dsRNA showed a high gene-silencing effect. Notably, our pET28-BL21(DE3) RNase III-system provides a novel method for the mass production of dsRNA at low cost and high efficiency, which may promote gene function analysis and RNAi-based pest management. © 2020 Society of Chemical Industry.

9.
Med Sci Monit ; 26: e918207, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32037392

RESUMO

BACKGROUND Clinical relapse in acute myeloid leukemia (AML) is associated with the reduced treatment response of leukemia stem cells (LSCs). This study aimed to investigate the effects of the ginseng derivative, ginsenoside Rg1 (Rg1), on CD34+CD38- LSCs derived from KG1a human acute myeloid leukemia cells. MATERIAL AND METHODS CD34+CD38- LSCs were isolated from KG1a human acute myeloid leukemia cells by cell sorting. CD34+CD38- KG1alpha LSCs were divided into the control group and the Rg1 group (treated with Rg1). The cell counting kit-8 (CCK-8) assay evaluated the proliferation of CD34+CD38- KG1alpha LSCs and flow cytometry studied the cell cycle. The mixed colony-forming unit (CFU-Mix) assay and staining for senescence-associated beta-galactosidase (SA-ß-Gal) evaluated cell senescence. Expression of sirtuin 1 (SIRT1) and tuberous sclerosis complex 2 (TSC2) were evaluated using Western blot and quantitative reverse transcription-polymerase chain reaction (qRT-PCR). RESULTS CD34+CD38- KG1alpha LSCs were isolated at 98.72%. Rg1 significantly reduced the proliferation of CD34+CD38- KG1alpha LSCs compared with the control group (p<0.05). Cells in the G0/G1 phase were significantly increased, and cells in the G2/M and S phase were significantly reduced compared with the control group (p<0.05). Rg1 significantly increased SA-ß-Gal and reduced CFU-Mix formation compared with the control group (p<0.05), significantly down-regulated SIRT1 expression in CD34+CD38- KG1alpha LSCs compared with the control group (p<0.05), and significantly reduced TSC2 expression in CD34+CD38- KG1alpha LSCs compared with the control group (p<0.05). CONCLUSIONS Rg1 inhibited cell proliferation and induced cell senescence markers in CD34+CD38- KG1alpha LSCs by activating the SIRT1/TSC2 signaling pathway.

10.
Nat Plants ; 6(2): 107-118, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32042158

RESUMO

Hornworts, liverworts and mosses are three early diverging clades of land plants, and together comprise the bryophytes. Here, we report the draft genome sequence of the hornwort Anthoceros angustus. Phylogenomic inferences confirm the monophyly of bryophytes, with hornworts sister to liverworts and mosses. The simple morphology of hornworts correlates with low genetic redundancy in plant body plan, while the basic transcriptional regulation toolkit for plant development has already been established in this early land plant lineage. Although the Anthoceros genome is small and characterized by minimal redundancy, expansions are observed in gene families related to RNA editing, UV protection and desiccation tolerance. The genome of A. angustus bears the signatures of horizontally transferred genes from bacteria and fungi, in particular of genes operating in stress-response and metabolic pathways. Our study provides insight into the unique features of hornworts and their molecular adaptations to live on land.

11.
Angew Chem Int Ed Engl ; 59(18): 7209-7213, 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32050043

RESUMO

Vibralactone is isolated from the basidiomycete fungus Boreostereum vibrans as one of the strongest lipase inhibitors. Its unusual ß-lactone-fused bicycle is derived from an aryl ring moiety by an oxidative ring-expansion prior to an intramolecular cyclization. Herein, we report the discovery of the cyclase VibC which belongs to the α/ß-hydrolase superfamily and is involved in the vibralactone biosynthesis. Biochemical and crystal studies suggest that VibC may catalyze an aldol or an electrocyclic reaction initiated by the Ser-His-Asp catalytic triad. For the aldol and pericyclic chemistry in living cells, VibC is a unique hydrolase performing the carbocycle formation of an oxepinone to a fused bicyclic ß-lactone. This presents a naturally occurring, new enzymatic reaction in both aldol and hydrolase (bio)chemistry that will guide future exploitation of these enzymes in synthetic biology for chemical-diversity expansion of natural products.

12.
Ground Water ; 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31970755

RESUMO

Aquifer hydraulic parameters are commonly inferred from constant-rate pumping tests, while variable pumping rates are frequently encountered in actual field conditions. In this study, we propose a generally applicable dimensionless form of the analytical solution for variable-rate pumping tests in confined aquifers. In particular, we adopt a piecewise-linear fitting of variable pumping rates and propose a new type-curve method for estimating the hydraulic conductivity (K) and specific storage (Ss ) of the investigated confined aquifer. For each test, a series of type curves, which depend on the variable pumping rates, the location of observation wells and the introduced first dimensionless inflection time, need to be provided for matching the observed drawdown data on a log-log graph. We first demonstrate the applicability and robustness of this method through a synthetic pumping test. Subsequently, we apply this method to analyze drawdown data from four pumping tests conducted within a multilayered aquifer/aquitard system in Wuxi city, Jiangsu Province, China. The parameter estimates are then compared with those reported by PEST. The K and Ss values estimated by the new type-curve method are found to be quite close to PEST-based estimates. Parameter estimation results demonstrate the difference in K and Ss values between observation wells. The difference could be attributed to the spatial heterogeneity in K and Ss . A future research topic may focus on the characterization of K and Ss heterogeneity with the currently available drawdown data from variable-rate pumping tests.

13.
Ying Yong Sheng Tai Xue Bao ; 31(1): 65-71, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-31957381

RESUMO

China is one of the countries with serious forest fires. Besides the methods of strengthening management of fire source and increasing forest fire monitoring and rescue efforts, improving the ability of forest itself to resist fire is also the key to prevent forest fires. In this study, we examined the characteristics of the bark across 11 main tree species in Korean pine broad-leaved forest at Jiaohe Forestry Experimental Area in Jilin Province. Fire resistance of bark acorss the tree species was evaluated comprehensively with four indices of water content, ash content, calorific value and oxygen index, using the methods of entropy weight, variance analysis and cluster analysis. Results showed that water content of bark was the highest in Phellodendron amurense. Calorific value of bark was the lowest and ash content was the highest in Ulmus davidiana. Oxygen index of bark was the highest in Fraxinus mandshurica. Bark fire resistance of 11 tree species followed the order of U. davidiana > Acer mono > Acer triflorum > Acer mandshuricum > F. mandshurica > Quercus mongolica > P. amurense > Tilia amurensis > Juglans mandshurica > Pinus koraiensis > Betula costata. The tree species in Korean pine broad-leaved forest could be classified to five categories according to bark fire resistance: U. davidiana belonged to the category of strongest fire-resistance; A. mono and A. triflorum belonged to the category of strong fire-resistance; A. mandshuricum, F. mandshurica, Q. mongolica, P. amurense, T. amurensis belonged to the category of common fire-resistance; J. mandshurica and P. koraiensis belonged to the category of weak fire-resistance; and B. costata belonged to the category of poor fire-resistance.


Assuntos
Pinus , Árvores , China , Florestas , Casca de Planta
14.
Aging (Albany NY) ; 12(1): 156-177, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31896739

RESUMO

A promising new strategy for cancer therapy is to target the autophagic pathway. However, comprehensive characterization of autophagy genes and their clinical relevance in cancer is still lacking. Here, we systematically characterized alterations of autophagy genes in multiple cancer lines by analyzing data from The Cancer Genome Atlas and CellMiner database. Interactions between autophagy genes and clinically actionable genes (CAGs) were identified by analyzing co-expression, protein-protein interactions (PPIs) and transcription factor (TF) data. A key subnetwork was identified that included 18 autophagy genes and 22 CAGs linked by 28 PPI pairs and 1 TF-target pair, which was EGFR targeted by RARA. Alterations in the expression of autophagy genes were associated with patient survival in multiple cancer types. RARA and EGFR were associated with worse survival in colorectal cancer patients. The regulatory role of EGFR in 5-FU resistance was validated in colon cancer cells in vivo and in vitro. EGFR contributed to 5-FU resistance in colon cancer cells through autophagy induction, and EGFR overexpression in 5-FU resistant colon cancer was regulated by RARA. The present study provides a comprehensive analysis of autophagy in different cancer cell lines and highlights the potential clinical utility of targeting autophagy genes.

15.
Ground Water ; 58(1): 132-142, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31407317

RESUMO

In arid northwestern China, as many inland areas around the world with arid or semi-arid climate, inland river flow recharges groundwater; vegetation pattern depends on the water table, which characterizes the landscapes of oasis, transition zone and desert, within different distances from an inland river. The water table conditions play an important role in water and land management-a high water table causes salinization within the oasis while a low water table causes desertification around the oasis. This study applies a theoretical-empirical method to calculating critical groundwater depths including the depth of critical groundwater level causing salinization (DCGS) and the depth of critical groundwater level causing desertification (DCGD); the calculations are validated with field observations in the Luocheng Irrigation District located in the middle reach of the Heihe River, an inland river of the northwestern China. Specifically, the calculated DCGS is 1.29 m for the case study area and the range of water table depth at the locations with saline soil is 0.5-1.2 m. The calculated DCGD for three vegetation communities, Nitraria tangutorum + Glycyrrhiza uralensis Fisch community, Tamarix chinensis + Phragmites australis community, and Alhagi sparsifolia + Phragmites communis, are 8.26, 11.26, and 13.26 m, respectively, basically within an observed range of 6.0-13.0 m in the study area. The critical depths can be used to design an engineering approach to control water tables and mitigate salinization and desertification problem for ecosystem restoration in the study region.


Assuntos
Ecossistema , Água Subterrânea , China , Clima Desértico , Ecologia , Água
16.
J Phys Condens Matter ; 32(10): 105701, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-31747646

RESUMO

The electronic stopping power for low-velocity ions (including protons, [Formula: see text]-particles, and [Formula: see text]) is investigated in a novel semimetal HgTe system, where the data are obtained with the aid of Ehrenfest dynamics combined with time-dependent density functional theory. For the light projectile ions (protons and [Formula: see text]-particles), the linear and nonlinear behaviors of electronic stopping power in three different channel directions are analyzed in detail. In the case where the projectile ion is a proton, the linear results for the threshold velocity are correlated with an indirect band gap; the direction of the electronic stopping power depends on the radial drag force, the channeling electronic density and the trapped charge. More notably, we report an interesting channel-geometry fact, i.e. that the electronic stopping power of HgTe is powerfully modulated by the impact parameters. The parallel off-center tracks increase the electronic stopping power, making it more consistent with the SRIM data. In the case of an [Formula: see text]-particle as the projectile ion, nonlinear behavior that varies with velocity can be ascribed to the charge transfer, which is another mode of energy dissipation. In addition, when the slightly heavier projectile [Formula: see text] travels through the medium HgTe, the projectile [Formula: see text] can capture more free charges than the protons and [Formula: see text]-particles under the same circumstances. Especially, for the projectile in the off-channel, the electronic stopping power is close to the SRIM data with the decrease of the impact parameter. These results extend the study of radiation damage to a new field of materials.

17.
J Am Chem Soc ; 142(1): 573-580, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31789517

RESUMO

Pre-schisanartanin C belongs to the family of Schisandra nortriterpenoids with potent antihepatitis, antitumor, and anti-HIV activities. This paper presents the enantioselective total synthesis of pre-schisanartanin C (1). An important step in the total synthesis of 1 is gold-catalyzed intramolecular cyclopropanation of a 1,8-enyne substrate bearing a secondary ester group at the propargylic position to prepare a bicyclo[6.1.0]nonane core. Additional highlights include (i) an asymmetric Diels-Alder reaction to install the initial C5 stereogenic center of 1 and (ii) a sequential Pd-catalyzed Stille coupling, regio- and stereoselective Sharpless asymmetric dihydroxylation, and a subsequent intramolecular lactonization to construct the side chain of 1. The developed chemistry paves the way for the total syntheses of other family members bearing highly rigid bicyclo[6.1.0]nonane cores.

18.
Neuron ; 105(5): 799-812.e5, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-31883788

RESUMO

Sensory experiences cause long-term modifications of neuronal circuits by modulating activity-dependent transcription programs that are vital for regulation of long-term synaptic plasticity and memory. However, it has not been possible to precisely determine the interaction between neuronal activity patterns and transcription factor activity. Here we present a technique using two-photon fluorescence lifetime imaging (2pFLIM) with new FRET biosensors to chronically image in vivo signaling of CREB, an activity-dependent transcription factor important for synaptic plasticity, at single-cell resolution. Simultaneous imaging of the red-shifted CREB sensor and GCaMP permitted exploration of how experience shapes the interplay between CREB and neuronal activity in the neocortex of awake mice. Dark rearing increased the sensitivity of CREB activity to Ca2+ elevations and prolonged the duration of CREB activation to more than 24 h in the visual cortex. This technique will allow researchers to unravel the transcriptional dynamics underlying experience-dependent plasticity in the brain.

19.
Ying Yong Sheng Tai Xue Bao ; 30(12): 4049-4058, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31840449

RESUMO

According to slope direction and position of the distribution of Juglans mandshurica natural secondary mixed forest in 12 sites of Changbai Mountain in Jilin Province, and combined with the age structure of J. mandshurica, we set up 109 plots. Based on the age-tree height data, we complied the site index of the forests. We used the three times tree height standard deviation method to eliminate abnormal data, 379 pairs age and tree height data were obtained from the 80 plots. Then, we used seven mathematical models for comparison and got simplex site index-oriented curve equation as H=28.0181(1-e-0.0341A)1.0503. The coefficient of determination R2 and the sum of squared residuals were 0.85 and 0.89, respectively, the base age was 50 years, the exponential interval was 2 m, and 7 site index curves of 16-28 m were obtained. According to different site types, polymorphic sites index model was established, and the power function fitting effect was best. Its equation was H=B0tB1, in which B0=10-9e0.9213SI, B1=-0.2139SI+5.6183. Finally, the polymorphic site index model equation was H=10-9e0.9213SIt-0.2139SI+5.6183. The exponential difference method and drop point test were conducted to check the accuracy of the two site index models. The results showed that the polymorphic site index had higher precision and it could accurately reflect the difference in tree height growth under different site types of J. mandshurica. Therefore, it could evaluate the site quality of natural secondary mixed forests of J. mandshurica in Changbai Mountain area of Jilin Province.


Assuntos
Juglans , Pinus , China , Florestas , Árvores
20.
Artigo em Inglês | MEDLINE | ID: mdl-31838830

RESUMO

Interferon (IFN)-λ plays an essential role in mucosal cells which exhibit strong antiviral activity. Lactobacillus plantarum (L. plantarum) has substantial application potential in the food and medical industries because of its probiotic properties. Alphacoronaviruses, especially porcine epidemic diarrhea virus (PEDV) and transmissible gastroenteritis virus (TGEV), cause high morbidity and mortality in piglets resulting in economic loss. The co-infection of the two viruses is becoming increasingly frequent. Therefore, it is particularly important to develop a new drug to prevent diarrhea infected with mixed viruses in piglets. In this study, we first constructed an anchored expression vector with CWA (C-terminal cell wall anchor) on L. plantarum. Second, we constructed two recombinant L. plantarum strains that anchored IFN-λ3 via pgsA (N­terminal transmembrane anchor) and CWA. Third, we demonstrated that both recombinant strains possess strong antiviral effects against coronavirus infection in the intestinal porcine epithelial cell line J2 (IPEC-J2). However, recombinant L. plantarum with the CWA anchor exhibited a more powerful antiviral effect than recombinant L. plantarum with pgsA. Consistent with this finding, Lb.plantarum-pSIP-409-IFN-λ3-CWA enhanced the expression levels of IFN-stimulated genes (ISGs) (ISG15, OASL, and Mx1) in IPEC-J2 cells more than did recombinant Lb.plantarum-pSIP-409-pgsA'-IFN-λ3. Our study verifies that recombinant L. plantarum inhibits PEDV and TGEV infection in IPEC-J2 cells, which may offer great potential for use as a novel oral antiviral agent in therapeutic applications for combating porcine epidemic diarrhea and transmissible gastroenteritis. This study was the first study that recombinant L. plantarum suppresses PEDV and TGEV infection of IPEC-J2 cells.

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