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1.
Nanoscale ; 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33020793

RESUMO

The volume change and concurrent stress evolution of electrode materials during the cycling of lithium-ion batteries can cause severe mechanical issues such as the fracture of active materials and electrodes, thus leading to safety issues and capacity fading. Recent years have witnessed a thriving interest to gain a complete understanding of battery electrode materials from the viewpoint of mechanics. This review paper aims at discussing battery electrode materials from a mechanical perspective to provide an overview of the recent innovative efforts in this field. On the one hand, we introduce the mechanical issues of active materials and electrodes in the electrochemical processes, along with a focus on the strategies developed for enhancing the mechanical strength of electrode materials and constructing mechanically robust electrodes. On the other hand, experimental and theoretical studies on the stress-regulated effects on electrochemical processes are discussed to demonstrate the intriguing role of mechanical stress as an enabler in electrochemistry. We also give an outlook on the promising research topics for understanding the material mechanical issues, reinforcing electrode materials and improving battery performance.

2.
Exp Eye Res ; : 108286, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33035554

RESUMO

Retinoblastoma (RB) is the most common intraocular malignant tumour in infants, and chemotherapy has been the primary therapy method in recent years. PRMT5 is an important member of the protein arginine methyltransferase family, which plays an important role in various tumours. Our study showed that PRMT5 was overexpressed in retinoblastoma and played an important role in retinoblastoma cell growth. EPZ015666 is a novel PRMT5 inhibitor, and we found that it inhibited retinoblastoma cell proliferation and led to cell cycle arrest at the G1 phase. At the same time, EPZ015666 regulated cell cycle related protein (P53, P21, P27, CDK2) expression. In brief, our study showed that PRMT5 promoted retinoblastoma growth, the PRMT5 inhibitor EPZ015666 inhibited retinoblastoma in vitro by regulating P53-P21/P27-CDK2 signaling pathways and slowed retinoblastoma growth in a xenograft model.

3.
Chin J Traumatol ; 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-33008740

RESUMO

PURPOSE: Several researches comparing the imageless navigation (IN) system and manual freehand (MF) approaches for the total hip arthroplasty (THA) have been published, but the curative effect is still contentious. This meta-analysis aims to systematically compare the differences between the two approaches. METHODS: Random controlled trials which compared the clinical efficacy between IN and MF approaches for THA were retrieved between June 1999 and June 2019, from PubMed, Embase, Cochrane Library, etc. Mean difference, odds ratio and corresponding 95% confidence intervals (CI) were used for estimating the effects of the two methods. I2 test and Chi-square test were used to test heterogeneity among studies. Statistical analyses were done using Review Manager Version 5.3. RESULTS: Eleven pieces of literature were presented. No statistical variation in IN and MF approaches on Harris hip score (HHS) (95% CI: -2.91, 1.47; p = 0.52), cup inclination (95% CI: -0.60, 1.95; p = 0.30), cup anteversion (95% CI: -2.85, 0.91; p = 0.31), cup abduction (95% CI: -3.65, 0.63; p = 0.17), length of incision (95% CI: -0.25, 0.29; p = 0.90), blood loss (95% CI: -69.14, 25.61; p = 0.37) and the decrease of hemoglobin (Hb) at 24 h after surgery (95% CI: -0.45, 0.40; p = 0.91), etc. However, the number of cases outside the safe zone in the IN group were less than in the MF group (95% CI: 0.08, 0.25; p < 0.00001). The deviation of cup inclination/anteversion in the IN group was smaller than in the MF group (95% CI: -3.65, -0.52; p = 0.009) vs. (95% CI: -6.16, 1.91; p = 0.0002). But the operation time in the IN group was longer than in the MF group (95% CI: 5.47, 11.60; p < 0.00001). CONCLUSIONS: IN system is more accurate than MF approaches in THA, but IN system needs more operation time. There is no difference between the approaches on HHS, cup inclination, cup anteversion, length of incision, blood loss and the decrease of Hb at 24 h after surgery.

4.
Ecotoxicol Environ Saf ; 206: 111382, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33011509

RESUMO

Waterborne exposure to highly persistent microplastic pollutants is a major concern for aquatic species worldwide. There are still gaps in knowledge on microplastics' potential transgenerational effects on offspring generation. Using zebrafish, this study investigated the survival and early development of offspring through a 21-day continuous parental treatment with polystyrene microplastics. The results showed that continuous waterborne exposure to high concentrations (>100 µg/L) of polystyrene microplastics (1 µm) for 21 days resulted in notable microplastic accumulation in adult fish intestines. Exposure at microplastic concentrations greater than 100 µg/L also induced significant changes in steroidogenic mRNA expression in zebrafish gonads. However, no significant changes in the cumulative number of eggs spawned and fertilization rate were observed at any parental exposure concentrations when compared to the control. Early development of derived offspring, in terms of hatching rate, body length, malformation rate and mortality rate, did not significantly differ from that of the control. This study showed that transgenerational effects of parental exposure to polystyrene microplastics in zebrafish might be negligible or recoverable. This study provided new results and insights on the transgenerational effects of microplastics on a freshwater fish species and can help to understand impacts of microplastics on freshwater ecosystems.

5.
J Sci Food Agric ; 2020 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-33012027

RESUMO

BACKGROUND: In this study, we investigated the effects of water-nitrogen interaction on the grain quality of two varieties of japonica rice grown on the North China Plain, based on evaluations of grain biochemical components, starch X-ray diffraction properties, thermal and pasting characteristics, and particle size distribution. RESULTS: We found that, under controlled irrigation, increasing levels of nitrogen resulted in a reduction in grain starch content and an increase in protein content. Nitrogen fertilization, irrigation, and their interaction had significant effects on the particle size and size distribution of rice flour. Under both controlled and flooding irrigation, the lowest values of pasting parameters for cultivars Xindao22 and Xindao10 were observed in response to moderate and high nitrogen application, respectively. Under flooding irrigation, Xindao22 exhibited lower mean value of gelatinization onset, peak, and conclusion temperatures and enthalpy in response to control irrigation, whereas in Xindao10 these parameters were relatively stable with respect to nitrogen and irrigation treatments. However, we observed no significant effects of either nitrogen or irrigation on amylopectin chain length distribution or starch relative crystallinity. CONCLUSION: Nitrogen application rate and irrigation methods had distinct effects on the physicochemical properties of flour derived from treated rice plants. The findings will provide support for scientific irrigation and fertilization in order to improve rice grain quality. © 2020 Society of Chemical Industry.

6.
Mol Cell ; 80(2): 237-245.e4, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33007200

RESUMO

Heterotrimeric G proteins communicate signals from activated G protein-coupled receptors to downstream effector proteins. In the phototransduction pathway responsible for vertebrate vision, the G protein-effector complex is composed of the GTP-bound transducin α subunit (GαT·GTP) and the cyclic GMP (cGMP) phosphodiesterase 6 (PDE6), which stimulates cGMP hydrolysis, leading to hyperpolarization of the photoreceptor cell. Here we report a cryo-electron microscopy (cryoEM) structure of PDE6 complexed to GTP-bound GαT. The structure reveals two GαT·GTP subunits engaging the PDE6 hetero-tetramer at both the PDE6 catalytic core and the PDEγ subunits, driving extensive rearrangements to relieve all inhibitory constraints on enzyme catalysis. Analysis of the conformational ensemble in the cryoEM data highlights the dynamic nature of the contacts between the two GαT·GTP subunits and PDE6 that supports an alternating-site catalytic mechanism.

7.
EBioMedicine ; 61: 103048, 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33039712

RESUMO

BACKGROUND: Microbial communities and their metabolic components in the gut are of vital importance for immune homeostasis and have an influence on the susceptibility of the host to a number of immune-mediated diseases like acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, little is known about the functional connections between microbiome and metabolome in aGVHD due to the complexity of the gastrointestinal environment. METHOD: Initially, gut microbiota and fecal metabolic phenotype in aGVHD murine models were unleashed by performing 16S ribosomal DNA gene sequencing and ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS)-based metabolomics. FINDINGS: The group with aGVHD experienced a significant drop in Lachnospiraceae_unclassified but an increase in the relative abundance of Clostridium XI, Clostridium XIVa and Enterococcus. Meanwhile, a lower content of tyrosine was observed in the gut of aGVHD mice. The correlation analysis revealed that tyrosine-related metabolites were inversely correlated with Clostridium XIVa, besides, Blautia and Enterococcus also displayed the negative tendency in aGVHD condition. Apart from exploring the importance and function of tyrosine, different tyrosine diets were offered to mice during transplantation. Additional tyrosine supplements can improve overall survival, ameliorate symptoms at the early stage of aGVHD and change the structure and composition of gut microbiota and fecal metabolic phenotype. In addition, aGVHD mice deprived from tyrosine displayed worse manifestations than the vehicle diet group. INTERPRETATION: The results demonstrated the roles and mechanisms of gut microbiota, indispensable metabolites and tyrosine in the progression of aGVHD, which can be an underlying biomarker for aGVHD diagnosis and treatment. FUNDING: This research was funded by the International Cooperation and Exchange Program (81520108002), the National Key R&D Program of China, Stem Cell and Translation Research (2018YFA0109300), National Natural Science Foundation of China (81670169, 81670148, 81870080 and 91949115) and Natural Science Foundation of Zhejiang Province (LQ19H080006).

8.
Artigo em Inglês | MEDLINE | ID: mdl-33055218

RESUMO

Plants utilize a two-tiered immune system consisting of pattern recognition receptor (PRR)-triggered immunity (PTI) and effector-triggered immunity (ETI) to defend themselves against pathogenic microbes. The receptor protein kinase BAK1 plays a central role in multiple PTI signaling pathways in Arabidopsis However, double mutants made by BAK1 and its closest paralog BKK1 exhibit autoimmune phenotypes, including cell death resembling a typical nucleotide-binding leucine-rich repeat protein (NLR)-mediated ETI response. The molecular mechanisms of the cell death caused by the depletion of BAK1 and BKK1 are poorly understood. Here, we show that the cell-death phenotype of bak1 bkk1 is suppressed when a group of NLRs, ADR1s, are mutated, indicating the cell-death of bak1 bkk1 is the consequence of NLR activation. Furthermore, introduction of a Pseudomonas syringae effector HopB1, which proteolytically cleaves activated BAK1 and its paralogs via either gene transformation or bacterium-delivery, results in a cell-death phenotype in an ADR1s-dependent manner. Our study thus pinpoints that BAK1 and its paralogs are likely guarded by NLRs.

9.
Wei Sheng Yan Jiu ; 49(5): 844-849, 2020 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-33070834

RESUMO

OBJECTIVE: To study the status of chronic disease multimorbidity of middle-aged and elderly people over 45 years old in China, and to analyze the influencing factors. METHODS: Using the data of the"China Health and Nutrition Survey(CHNS)", this survey has been carried out in 10 rounds nationwide since 1989. Multi-stage cluster random sampling was used to investigate rural and urban areas in 9 provinces and cities in China. In this study, the general socio-demographic characteristics, disease history, living habits and other information in the 2009 database were used to analyze the subjects who were collected blood samples. The prevalence of 8 common chronic diseases and multimorbidity such as hypertension, mixed-hyperlipidemia and hyperuricemia were described respectively. The Venn diagram in the R software package was used to calculate the multimorbidity of the disease. The χ~2 test and multiple correspondence analysis were used to explore the influencing factors of chronic disease multimorbidity in the middle-aged and elderly people in China. RESULTS: Among the 5316 subjects, the highest prevalence among 8 chronic diseases was hypertension(2143, 40. 3%). The lowest prevalence was myocardial infarction(87, 1. 4%). There were all together 1498 patients who had two kinds or more than two kinds of chronic diseases with a detection rate of 28. 18%. The most common multimorbidity were hypertension+hyperuricemia(199, 13. 30%), followed by hypertension + mixed-hyperlipidemia(191, 12. 77%). Hypertension+hyperuricemia+mixed-hyperlipidemia was the most common combination of the three chronic diseases(103, 6. 89%). Age(Kendull=0. 158, P<0. 001), region(χ~2=30. 129, P<0. 001), BMI(Kendull=0. 344, P<0. 001) and marital status(χ~2=21. 923, P<0. 001) were associated with the number of multimorbidities. Correspondence analysis showed that subjects aged 65 to 74, living in cities and sleeping less than 7 hours were more likely to have multimorbidity. CONCLUSION: The prevalence of chronic disease multimorbidity among middle-aged and elderly residents in China is high. Older age, unmarried, overweight and obesity, too little or too much sleep may increase the risk of multimorbidity.

10.
J Vet Med Sci ; 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33071252

RESUMO

An enzyme-linked immunosorbent assay (ELISA) based on recombinant SAG1-related sequence 2 of Toxoplasma gondii (rTgSRS2) was developed to detect toxoplasmosis in cats. The specificity and sensitivity of rTgSRS2 ELISA were confirmed using a series of serum samples from T. gondii-experimentally infected mice. A total of 76 field samples from cats were examined by the developed ELISA. The rTgSRS2 ELISA showed a good diagnostic performance characterized by high concordance (88.16) and kappa value (0.76) with latex agglutination test (LAT). The sensitivity and specificity of the test were 92.68% and 82.86%, respectively. These results suggest that the ELISA based on rTgSRS2 could be a useful tool for serodiagnosis of T. gondii infection in cats.

11.
Mol Cell Biochem ; 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33074446

RESUMO

The present study screened the effect of Myricitrin on cognitive deficits post-cerebral ischemic stroke and the involved mechanism. The rats were submitted to middle cerebral artery occlusion (MCAO) and were treated with sodium butyrate or Myricitrin (15 and 30 mg/kg) for 28 days. The spatial memory was studied by Morris water maze (MWM). After 4 weeks, the rats were euthanized and hippocampus region was utilized for neurochemical and biochemical changes. The extent of histone acetylation was studied by ELISA. Protein levels were analyzed by Western blot analysis. The mRNA levels were analyzed by polymerase chain reaction (PCR). In silico bioinformatics docking studies were done for target confirmation of Myricitrin. The treatment of Myricitrin showed improved memory in MWM compared to rats treated with vehicle, and the effects of Myricitrin were similar to sodium butyrate-treated rats. At a dose of 30 mg/kg Myricitrin, the histone deacetylase content was decreased, the expression levels of BDNF were increased, the levels of acetylated H3 and H4 along with Syn-I in the hippocampus region were over-expressed compared to control vehicle-treated rats. However, at low dose, i.e., 15 mg/kg Myricitrin failed to show alterations in biochemical as well as neurochemical markers. Docking studies suggested the BDNF and Sun-I as potential target proteins of Myricitrin. The cognitive ameliorating effect of Myricitrin post-cerebral ischemia stroke can be attributed to increased expression of BDNF and Syn-I and modulation of histone acetylation.

12.
Artigo em Inglês | MEDLINE | ID: mdl-32875975

RESUMO

AIM: The aim of the present study is to investigate the effect of flavonoids from stem and leaf of Scutellaria baicalonsis Georgi (SSF) on multi-sites phosphorylation of tau protein in cerebral cortex and hippocampus of rats induced by okadaic acid (OA) and the regulative mechanism of the protein kinases. METHODS: The model of AD-like memory impairment and neuronal injuries was established in male SD rats who were microinjected with OA (200 ng/kg) to establish a memory impairment model and screened for successful model rats by Morris water maze on day 21 after surgery. The successful model rats were continuously administered with intragastric infusion (ig) SSF 25, 50, and 100 mg/kg or Ginkgo biloba leaves flavonoids (GLF) 200 mg/kg for 36 d. The relative protein expressed levels of phosphorylated tau protein at sites of Ser199, Ser202, Ser214, Ser404 and Thr231, protein kinases (CDK5, PKA, pTyr216-GSK3ß and pSer9-GSK3ß) were detected by Western blotting. RESULTS: The relative protein expressed levels of p-tau(Ser199), p-tau(Ser202), p-tau(Ser214), p-tau(Ser404) p-tau(Thr231), and pTyr216-GSK3ß were significantly increased in both cerebral cortex and hippocampus regions of the model rats subjected to intracerebroventricular injection of OA (P<0.01), while the protein expressed levels of CDK5, PKA and pSer9- GSK3ß (P<0.01) were reduced. SSF can dramatically reverse these increments in phosphorylated tau protein levels (P<0.01) and differently regulate the protein expressed levels of CDK5, PKA, and GSK3ß (P<0.01) in rats' cerebral cortex and hippocampus induced by OA. GLF also exhibits a similar effect on SSF. CONCLUSION: The results demonstrated that SSF could inhibit the hyperphosphorylation of tau in rats' cerebral cortex and hippocampus induced by microinjection of OA, which may be related to the activities of protein kinase CDK5, PKA, and GSK3ß.

13.
Biol Reprod ; 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32902612

RESUMO

Transforming growth factor ß (TGFß) signaling regulates multifaceted reproductive processes. It has been shown that the type 1 receptor of TGFß (TGFBR1) is indispensable for female reproductive tract development, implantation, placental development, and fertility. However, the role of TGFß signaling in decidual development and function remains poorly defined. Our objective is to determine the impact of uterine-specific deletion of Tgfbr1 on decidual integrity, with a focus on the cellular and molecular properties of the decidua during development. Our results show that the developmental dynamics of the decidua are altered in TGFBR1 conditionally depleted uteri from embryonic day (E) 5.5 to E8.5, substantiated by downregulation of genes associated with inflammatory responses and uterine natural killer cell abundance, reduced presence of non-decidualized fibroblasts in the antimesometrial region, and altered decidual cell development. Notably, conditional ablation of TGFBR1 results in the formation of decidua containing more abundant alpha smooth muscle actin (ACTA2)-positive cells at the peripheral region of the antimesometrial side versus controls at E6.5-E8.5. This finding is corroborated by upregulation of a subset of smooth muscle marker genes in Tgfbr1 conditionally-deleted decidua at E6.5 and E8.5. Moreover, increased cell proliferation and enhanced decidual ERK1/2 signaling were found in Tgfbr1 conditional knockout mice upon decidual regression. In summary, conditional ablation of TGFBR1 in the uterus profoundly impacts the cellular and molecular properties of the decidua. Our results suggest that TGFBR1 in uterine epithelial and stromal compartments is important for the integrity of the decidua, a transient but crucial structure that supports embryo development.

14.
Cell Chem Biol ; 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32916088

RESUMO

MKK4/7 are kinases that phosphorylate JNKs and regulate the MAPK signaling pathway. Their overexpression has been associated with tumorigenesis and aggressiveness in cancers such as breast, prostate, non-small cell lung, and pediatric leukemia, making them a potential target for inhibitor development. Here, we report the discovery, development, and validation of a dual MKK4/7 inhibitor, BSJ-04-122, that covalently targets a conserved cysteine located before the DFG motif and displays excellent kinome selectivity. BSJ-04-122 exhibits potent cellular target engagement and induces robust target-specific downstream effects. The combination of the dual MKK4/7 inhibitor with a selective, covalent JNK inhibitor demonstrated an enhanced antiproliferative activity against triple-negative breast cancer cells. Taken together, the results show that BSJ-04-122 represents a pharmacological probe for MKK4/7 and credential covalent targeting as a way to explore the therapeutic potential of these kinases.

15.
Int J Mol Sci ; 21(18)2020 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-32932732

RESUMO

Radiotherapy is an important modality for the local control of human cancers, but the radioresistance induced by aberrant apoptotic signaling is a hallmark of cancers. Restoring the aberrant apoptotic pathways is an emerging strategy for cancer radiotherapy. In this study, we determined that targeting cell division cycle 20 (CDC20) radiosensitized colorectal cancer (CRC) cells through mitochondrial-dependent apoptotic signaling. CDC20 was overexpressed in CRC cells and upregulated after radiation. Inhibiting CDC20 activities genetically or pharmacologically suppressed the proliferation and increased radiation-induced DNA damage and intrinsic apoptosis in CRC cells. Mechanistically, knockdown of CDC20 suppressed the expression of antiapoptotic protein Mcl-1 but not other Bcl-2 family proteins. The expressions of CDC20 and Mcl-1 respond to radiation simultaneously through direct interaction, as evidenced by immunoprecipitation and glutathione S-transferase (GST) pull-down assays. Subsequently, decreased Mcl-1 expression inhibited the expression level of phosphorylated checkpoint kinase 1 (p-Chk1), thereby resulting in impaired DNA damage repair through downregulating the homologous recombination repair protein Rad51 and finally causing apoptotic signaling. In addition, both CDC20 and Chk1 inhibitors together, through in vivo studies, confirmed the radiosensitizing effect of CDC20 via inhibiting Mcl-1 and p-Chk1 expression. In summary, our results indicate that targeting CDC20 is a promising strategy to improve cancer radiotherapy.

16.
Chin J Integr Med ; 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32946039

RESUMO

OBJECTIVE: To assess the effect and safety of bloodletting puncture at hand twelve Jing-Well points (HTWPs) in acute stroke patients with conscious disturbance. METHODS: In this multi-center and randomized controlled trial, 360 patients suffered from ischemic or hemorrhagic stroke with conscious disturbance within 48 h from the onset of symptom were divided into bloodletting (180 cases) and control (180 cases) groups using a block randomization. Patients in both groups received routine Western medicine, and patients in the bloodletting group received additional bloodletting puncture at HTWPs on admission immediately before conventional treatment. The primary outcome measure was Glasgow Coma Scale (GCS) score and the secondary outcomes included blood pressure, respiratory rate and pulse rate. All variables were evaluated at baseline (before bloodletting), 0 (after bloodletting immediately), 15, 30, 50 and 80 min post bloodletting. RESULTS: At 80 min post bloodletting, the proportion of patients with improved consciousness in the bloodletting group was greater than the control group (P<0.05). In the separate analysis of moderate consciousness disturbance subgroup, bloodletting therapy benefited ischemic patients, and improved the eye and language response of GCS score at 15, 30, 50, 80 min post bloodletting (P<0.05 or P<0.01). No significant differences were observed regarding the secondary outcomes between two groups (P>0.05). CONCLUSION: The bloodletting puncture at HTWPs was safe and could improve conscious levels of ischemic stroke patients, highlighting a first-aid intervention for acute stroke. (Registration No. ChiCTR-INR-16009530).

17.
J Cell Mol Med ; 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32996285

RESUMO

Long noncoding RNAs have key roles in glioma progression. However, the function and mechanisms of action of the long noncoding RNA, LINC00346, in glioma remain unclear. In our study, we observed that LINC00346 levels were increased in glioma tissue samples, and according to Gene Expression Profiling Interactive Analysis, its levels were related to disease-free survival and overall survival rates, suggesting that a high level of LINC00346 expression corresponds to a poor prognosis. We next confirmed the high levels of LINC00346 expression in glioma tissues and cell lines and showed that LINC00346 knockdown suppressed glioma cell proliferation, migration and invasion; promoted apoptosis; and delayed tumour growth. Moreover, the oncogenic function of LINC00346 may be explained, in part, by the down-regulation of miR-340-5p and the de-repression of ROCK1. We showed that LINC00346 may function as a competing endogenous RNA of miR-340-5p, thereby de-repressing ROCK1. This study revealed a new regulatory network in glioma and identified potential therapeutic targets for this cancer.

18.
Artigo em Inglês | MEDLINE | ID: mdl-32972216

RESUMO

CRF01_AE and CRF07_BC are two widespread HIV-1 strains among different high-risk populations, including men who have sex with men (MSM), in China. This co-epidemic of various HIV strains enables the production of second-generation recombinants. In this study, we detected a novel HIV-1 CRF01_AE/CRF07_BC recombinant from LN321945, a MSM lived in Liaoning province, northeast China. The phylogenetic and recombination analyses indicated the near full-length genome (NFLG) sequence of LN321945 had six recombination breakpoints, with three CRF07_BC fragments inserted into a CRF01_AE backbone. Further subregion trees analysis revealed that both CRF01_AE and CRF07_BC fragments were derived from two predominant HIV-1 strains among MSM. Additionally, the NFLG of LN321945 was revealed to be clustered closely to another CRF01_AE/CRF07_BC recombinant previously identified in Shaanxi province, northwest China, but these two recombinants had distinct recombination structure and origin of CRF01_AE fragments. Hence, this study identified a second-generation recombinant between the main strains circulating among MSM, indicating more complicated trend of HIV-1 epidemic in China.

19.
Artigo em Inglês | MEDLINE | ID: mdl-32867377

RESUMO

Human activities such as deforestation and urbanization have affected the regional habitat quality of the Poyang Lake area. To evaluate the evolution of habitat quality and its influencing factors in the area, we used Classification and Regression Trees (CART) to interpret the land-use status and used the InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) model to analyze the characteristics of changes in habitat quality in the Poyang Lake Eco-Economic Zone (PLEEZ) from 1988 to 2018. The results show that, from 1988 to 2018, land use in the PLEEZ underwent significant changes. The changes in land use led to a gradual increase in habitat degradation and a gradual decrease in habitat quality in the study area. Rapid urbanization notably decreased the habitat quality in the study area. However, at the same time, the ecological protection projects such as returning farmland to forests slowed the decline in habitat quality. Driven by these two factors, habitat quality in the PLEEZ gradually declined but the rate of its decline was suppressed. The findings of this study are of great significance for the coordinated development of social, economic, and ecological development in the PLEEZ and similar areas.

20.
PLoS One ; 15(9): e0238152, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32970678

RESUMO

This research aims to create a hierarchical framework for the development of a platform business model based on big data. However, this hierarchical framework must consider unnecessary attributes and the interrelationships between the aspects and the criteria. Hence, fuzzy set theory is used for screening out the unnecessary attributes, a decision-making and trial evaluation laboratory (DEMATEL) is proposed to manage the complex interrelationships among the aspects and attributes, and interpretive structural modeling (ISM) is used to divide the hierarchy and finally construct a hierarchical framework. The results reveal that (1) value proposition and community building in value production are fundamental links; (2) information technology and information management in value production are technical supports; (3) customer development in value marketing is the power source; and (4) value acquisition is the last link, which is established on the basis of and influenced by value marketing and value network. This hierarchical framework aims to guide the platform toward the application of big data. This study also proposes engagement of stakeholders for promoting value creation and establishing a sound business model from multiple levels and links.

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