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1.
J Hazard Mater ; 401: 123438, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-32763717

RESUMO

Cadmium (Cd), a well-known environmental pollutant, can lead to placental insufficiency and fetal growth restriction. However, the underlying mechanism is unknown. The purpose of our study is to explore the effect of Cd on placental angiogenesis and its mechanism using in vitro and in vivo models. Results found that gestational Cd exposure obviously decreased placental weight and impaired placental vascular development in mice. Correspondingly, Cd exposure evidently downregulated the expression of VEGF-A protein (a key indicator of angiogenesis) and progesterone receptor (PR) in placental trophoblasts. Further experiment showed that lentivirus PR overexpression reversed Cd-caused the reduction of VEGF-A level in human placental trophoblasts. In addition, Cd significantly reduced progesterone level, down-regulated the expression of key progesterone synthase (StAR, CYP11A1), and activated mitochondrial stress response and GCN-2/p-eIF2α signaling in placental trophoblasts. Additional experiment showed that GCN-2 siRNA pretreatment markedly alleviated Cd-activated mitochondrial stress response, restored Cd-downregulated the expression of CYP11A1, reversed Cd-reduced the level of progesterone and VEGF-A in human placental trophoblasts. Finally, our case-control study confirmed that impaired placental angiogenesis and reduced progesterone level occurred in all-cause small for gestational age placenta. Taken together, environmental exposure to Cd impairs fetal growth and placental angiogenesis via GCN-2-mediated mitochondrial stress.

2.
BMC Infect Dis ; 20(1): 844, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33198666

RESUMO

BACKGROUND: Raised intracranial pressure (ICP) and insufficient antifungal regimens are the two main factors result to unsatisfactory outcomes in non-HIV cryptococcal meningitis (CM) patients. In this study, we try to discuss that whether triple therapy of amphotericin B (AmB), fluconazole, 5-flucytosine (5-FC) plus ventriculoperitoneal shunts (VPS) is superior to AmB, 5-FC, fluconazole plus intermittent lumbar puncture in induction therapy in non-HIV CM patients with increased ICP. METHODS: We reviewed 66 clinical records from non-HIV CM patients with increased ICP. The demographic and clinical characteristics, BMRC staging, cerebrospinal fluid profiles (CSF), brain magnetic resonance imaging, treatment, and outcomes of these individuals were retrospectively analyzed. All non-HIV CM patients with increased ICP (≥ 25 cmH2O) were divided into two groups, including 27 patients treated with triple antifungal agents and 39 patients treated with the same triple therapy plus VPS. RESULTS: Triple therapy plus VPS group had more satisfactory outcomes, more CSF sterilization at 10 weeks follow-up, lower CSF opening pressure, lower BMRC staging scores one week after VPS, less CSF C. neoformans counts and CSF culture positive. Besides, these patients had shorter hospital stay than triple therapy group. CONCLUSIONS: Triple antifungal agents combined with VPS could effectively reduce ICP, had faster rate of clearance of C. neoformans counts, more improved neurological function, shorten hospitalization time and better outcomes in non-HIV CM patients with increased ICP. Our study indicated that triple therapy plus early VPS may be an optimal treatment for non-HIV CM patients with increased ICP.

3.
Artigo em Inglês | MEDLINE | ID: mdl-33211541

RESUMO

Few studies have simultaneously examined the underlying mechanisms of the link between violent video games exposure (VVGE) and aggression (as proposed by different theories) to examine how they explain the relationship between the concepts as independent-dependent variables. This study used a multi-informant design to examine the relationship between VVGE and the functions (proactive and reactive) of aggressive behaviors by comparing three mediating mechanisms: anger, moral disengagement, and cognitive impulsivity. The sample consisted of 2,095 Chinese children and adolescences (48.9 percent girls; Mage = 11.12 years, SD = 1.70) and their mothers. After controlling for age, gender, socioeconomic status, child maltreatment, and problematic traits, structural equation modeling indicated that anger and moral disengagement play mediating roles between VVGE and proactive and reactive aggression, but cognitive impulsivity only plays a mediating role between VVGE and reactive aggression. The discussion emphasizes the importance of creating prevention programs for anger, moral disengagement, and cognitive impulsivity to break the VVGE-to-aggression cycle, and provides suggestions for future research.

4.
Aging (Albany NY) ; 12(21): 21923-21941, 2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33186122

RESUMO

Alternative splicing events are a major source of transcript and protein diversity in eukaryotes. Aberrant alternative splicing events have been increasingly reported in various cancers, including gastric cancer. To further explore the prognostic significance of alternative splicing events in gastric cancer patients, a comprehensive and systematic investigation was conducted by integrating alternative splicing event data and clinical information. Univariate Cox regression analysis identified 1383 alternative splicing events to be significantly associated with the overall survival of gastric cancer patients. Then, least absolute shrinkage and selection operator (LASSO) and multivariate Cox analyses were performed for the development of prognostic signatures. The final prognostic signature based on all seven types of alternative splicing events can act as an independent prognostic indicator after multivariate adjustment of several clinical parameters. Furthermore, the correlation and function analysis identified CELF2, BAG2, RBFOX2, PTBP2 and QKI as hub splicing factors, and the focal adhesion signaling pathway was most significantly correlated with survival-associated alternative splicing events. The results of this study may establish a foundation for further research investigating the underlying mechanism of alternative splicing events in the progression of gastric cancer.

5.
Cell Death Dis ; 11(9): 818, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32999280

RESUMO

As a deubiqutinase Otub1 stabilizes and promotes the oncogenic activity of the transcription factor c-Maf in multiple myeloma (MM), a malignancy of plasma cells. In the screen for bioactive inhibitors of the Otub1/c-Maf axis for MM treatment, nanchangmycin (Nam), a polyketide antibiotic, was identified to suppress c-Maf activity in the presence of Otub1. By suppressing Otub1, Nam induces c-Maf polyubiquitination and subsequent degradation in proteasomes but does not alter its mRNA level. Consistently, Nam downregulates the expression of CCND2, ARK5, and ITGB7, the downstream genes regulated by c-Maf, and promotes MM cell apoptosis as evidenced by PARP and Caspase-3 cleavage, as well as Annexin V staining. In line with the hypothesis, overexpression of Otub1 partly rescues Nam-induced MM cell apoptosis, and interestingly, when Otub1 is knocked down, Nam-decreased MM cell survival is also partly ablated, suggesting Otub1 is essential for Nam anti-MM activity. Nam also displays potent anti-MM activity synergistically with Doxorubicin or lenalidomide. In the in vivo assays, Nam almost completely suppresses the growth of MM xenografts in nude mice at low dosages but it shows no toxicity. Given its safety and efficacy, Nam has a potential for MM treatment by targeting the Otub1/c-Maf axis.

6.
Neurosci Bull ; 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33051817

RESUMO

In the developing spinal cord, the majority of oligodendrocyte progenitor cells (OPCs) are induced in the ventral neuroepithelium under the control of the Sonic Hedgehog (Shh) signaling pathway, whereas a small subset of OPCs are generated from the dorsal neuroepithelial cells independent of the Shh pathway. Although dorsally-derived OPCs (dOPCs) have been shown to participate in local axonal myelination in the dorsolateral regions during development, it is not known whether they are capable of migrating into the ventral region and myelinating ventral axons. In this study, we confirmed and extended the previous study on the developmental potential of dOPCs in the absence of ventrally-derived OPCs (vOPCs). In Nestin-Smo conditional knockout (cKO) mice, when ventral oligodendrogenesis was blocked, dOPCs were found to undergo rapid amplification, spread to ventral spinal tissue, and eventually differentiated into myelinating OLs in the ventral white matter with a temporal delay, providing genetic evidence that dOPCs are capable of myelinating ventral axons in the mouse spinal cord.

7.
Steroids ; 164: 108751, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33075399

RESUMO

Ergosterol peroxide (EP) has considerable potential effect against the proliferation of tumor cells. Here, we established a new approach for EP content detection through liquid chromatography-tandem mass spectrometry. The specificity, limit of detection (LOD)/quantitative (LOQ), linearity and range, accuracy, repeatability, and intermediate precision were tested. The EP retention time was 7.18 min. The linear relationship between the mass concentration of nonylphenol and the chromatographic peak area was good within the EP concentration range of 0.1-2.0 µg/mL. The correlation coefficient was 0.994, the regression equation was Y = 27 409.8 × X - 1114.67, the average recovery rate was 82.77%, the relative standard deviation was 11.1%, the LOQ was 50 ng/mL, and the LOD was 20 ng/mL. The detection technique was convenient, accurate, reproducible, and rapid. Therefore, this method could be used for deep liquid fermentation, providing a basis for EP to serve as a quality standard for the fermentation of Paecilomyces cicadae.

8.
Light Sci Appl ; 9: 160, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32963772

RESUMO

The advent of low-dimensional materials with peculiar structure and superb band properties provides a new canonical form for the development of photodetectors. However, the limited exploitation of basic properties makes it difficult for devices to stand out. Here, we demonstrate a hybrid heterostructure with ultrathin vanadium dioxide film and molybdenum ditelluride nanoflake. Vanadium dioxide is a classical semiconductor with a narrow bandgap, a high temperature coefficient of resistance, and phase transformation. Molybdenum ditelluride, a typical two-dimensional material, is often used to construct optoelectronic devices. The heterostructure can realize three different functional modes: (i) the p-n junction exhibits ultrasensitive detection (450 nm-2 µm) with a dark current down to 0.2 pA and a response time of 17 µs, (ii) the Schottky junction works stably under extreme conditions such as a high temperature of 400 K, and (iii) the bolometer shows ultrabroad spectrum detection exceeding 10 µm. The flexible switching between the three modes makes the heterostructure a potential candidate for next-generation photodetectors from visible to longwave infrared radiation (LWIR). This type of photodetector combines versatile detection modes, shedding light on the hybrid application of novel and traditional materials, and is a prototype of advanced optoelectronic devices.

9.
Cell Mol Neurobiol ; 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32876898

RESUMO

The original version of the article unfortunately contained an error in positive control group of Figure 8.

10.
BMC Geriatr ; 20(1): 369, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32977753

RESUMO

BACKGROUND: To investigate the current situation regarding the activities of daily living (ADL) of older adults living at home in Ningxia Hui Autonomous Region of China and to analyze the associated factors of ADL performance so that we can provide references for the implementation of pension policies and long-term care insurance of older adults living at home. METHODS: We surveyed a total of 1040 older adults who live at home and receive home-based care in Ningxia Hui Autonomous Region by a face-to-face evaluation. A logistic regression model was used to analyze the factors associated with ADL performance. RESULTS: In the study, 82.79% of the older adults living at home can live independently. A total of 11.92% of the older adults have mild dysfunction, 4.33% have moderate dysfunction, and 0.96% have severe dysfunction. Multiple logistic analyses indicated that older adults with very difficult economic conditions (OR 3.212; 95% CI(1.209-8.534)) and without a spouse (OR 1.616; 95% CI(1.098-2.377)) were significantly associated with ADL limitations. In addition, the risks of ADL limitations in older adults aged 60-69 years and 70-79 years were 0.187 and 0.4307 times, respectively, that of older adults over 80 years old. The risk of ADL limitations in older adults of the Han nationality was 0.605 times that of the minority population. More highly educated and older adults without diseases have a lower risk of ADL limitations. CONCLUSIONS: Compared with the national average in China, the number of ADL limitations of older adults in Ningxia is greater and is associated with advanced age, ethnic minority status, low education level, low income, lacking a spouse and having diseases. As the number of older adults increases, maintaining and improving their ability to perform ADL and providing comfortable pension services and health services urgently need to be solved.

11.
Epidemiol Infect ; 148: e238, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32993821

RESUMO

The mortality of coronavirus disease 2019 (COVID-19) differs between countries and regions. This study aimed to clarify the clinical characteristics of imported and second-generation cases in Shaanxi. This study included 134 COVID-19 cases in Shaanxi outside Wuhan. Clinical data were compared between severe and non-severe cases. We further profiled the dynamic laboratory findings of some patients. In total, 34.3% of the 134 patients were severe cases, 11.2% had complications. As of 7 March 2020, 91.8% patients were discharged and one patient (0.7%) died. Age, lymphocyte count, C-reactive protein, erythrocyte sedimentation rate, direct bilirubin, lactate dehydrogenase and hydroxybutyrate dehydrogenase showed difference between severe and no-severe cases (all P < 0.05). Baseline lymphocyte count was higher in survived patients than in non-survivor case, and it increased as the condition improved, but declined sharply when death occurred. The interleukin-6 (IL-6) level displayed a downtrend in survivors, but rose very high in the death case. Pulmonary fibrosis was found on later chest computed tomography images in 51.5% of the pneumonia cases. Imported and second-generation cases outside Wuhan had a better prognosis than initial cases in Wuhan. Lymphocyte count and IL-6 level could be used for evaluating prognosis. Pulmonary fibrosis as the sequelae of COVID-19 should be taken into account.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China/epidemiologia , Infecções por Coronavirus/sangue , Infecções por Coronavirus/complicações , Infecções por Coronavirus/mortalidade , Feminino , Humanos , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/complicações , Pneumonia Viral/mortalidade , Estudos Retrospectivos , Adulto Jovem
12.
BMC Genomics ; 21(1): 641, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938401

RESUMO

BACKGROUND: In 2014, a novel tick-borne virus of the Flaviviridae family was first reported in the Mogiana region of Brazil and named the Mogiana tick virus (MGTV). Thereafter, the Jingmen tick virus (JMTV), Kindia tick virus (KITV), and Guangxi tick virus (GXTV)-evolutionarily related to MGTV-were reported. RESULTS: In the present study, we used small RNA sequencing (sRNA-seq) to detect viruses in ticks and discovered a new MGTV strain in Amblyomma testudinarium ticks collected in China's Yunnan Province in 2016. We obtained the full-length genome sequence of this MGTV strain Yunnan2016 (GenBank: MT080097, MT080098, MT080099 and MT080100) and recommended it for its inclusion in the NCBI RefSeq database for future studies on MGTV, JMTV, KITV and GXTV. Phylogenetic analysis showed that MGTV, JMTV, KITV and GXTV are monophyletic and belong to a MGTV group. Furthermore, this MGTV group of viruses may be phylogenetically related to geographical regions that were formerly part of the supercontinents Gondwana and Laurasia. CONCLUSIONS: To the best of our knowledge, this is the first study in which 5' and 3' sRNAs were used to generate full-length genome sequences of, but not limited to, RNA viruses. We also demonstrated the feasibility of using the sRNA-seq based method for the detection of viruses in pooled two and even possible one small ticks. MGTV may preserve the characteristic of ancient RNA viruses, which can be used to study the origin and evolution of RNA viruses. In addition, MGTV can be used as novel species for studies in phylogeography.

13.
Ann Diagn Pathol ; 49: 151633, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32977235

RESUMO

OBJECTIVES: We investigated whether serum tumor markers (STMs) represent a valuable noninvasive tool to predict epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer (NSCLC) patients. METHODS: A retrospective analysis was performed for 143 NSCLC patients at the Peking University International Hospital from December 2014 to December 2019. EGFR mutations in the tumor tissues were identified by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and next generation sequencing (NGS). The relationships between EGFR mutation and several clinicopathological features were analyzed. RESULT: EGFR mutation were found more frequently in female (56.67%, P = 0.01), never-smokers (55.26%, P = 0.004), and those with lung adenocarcinoma (ADC) (52.17%, P < 0.001). The positive mutation rate for the EGFR gene were higher in the squamous cell carcinoma antigen (SCCA)group (≤1.5 ng/ml) and in the gastrin-releasing peptide precursor (preGRP) increased group (≥69.2 pg/ml), and this difference was statistically significant (P < 0.05). Univariate logistic regression analysis demonstrated that females (Odd ratio [OR]: 2.435, 95% confidence interval [CI]: 1.232, 4.813, P = 0.01) and never-smokers (OR = 0.370; CI = 0.186, 0.734; P = 0.004), lung adenocarcinoma patients (OR = 9.091; CI = 2.599, 21.800; P = 0.001), the SCC group (≤1.5 ng/ml) (OR = 0.331, CI = 0.120, 0.914; P = 0.033), and the preGRP group (≥69.2 pg/ml) (OR = 5.478, CI = 1.462, 20.528; P = 0.012) patients were risk factors for EGFR gene mutation. Multivariate logistic regression analysis demonstrated that lung ADC and proGRP elevation were independent risk factors for predicting EGFR gene positivity (P < 0.05). CONCLUSION: STMs are associated with mutant EGFR status and could be integrated with other clinical factors to facilitate the classification of EGFR mutation status among NSCLC patients.

14.
Neurosci Lett ; 738: 135383, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32937190

RESUMO

Hyperglycemia is common and associated with poor outcome in acute ischemic stroke patients. Neutrophil extracellular traps (NETs) are increased either in diabetes or ischemic stroke. We aimed to determine the role of NETs in acute ischemic stroke with hyperglycemia as it has not been clarified. NETs were observed in thrombi retrieved from ischemic stroke patients undergoing endovascular treatment. Citrullinated histone H3 was much more abundant in thrombi from hyperglycemic patients than in those from normoglycemic patients. BKS-db/db and wild-type mice injected with glucose were used to establish the permanent middle cerebral artery occlusion model with hyperglycemia. NETs induced by hyperglycemia were detected in the peri-ischemic brain tissue. Inhibition of NET formation decreased the infarction volume both in db/db and wild-type mice with hyperglycemia. Neurological function deficits were alleviated by blocking NET formation. These findings suggest that NETs increased by hyperglycemia play a role in exacerbation of ischemic brain damage.

15.
BMC Vet Res ; 16(1): 317, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32859190

RESUMO

BACKGROUND: The gram-negative Coxiella burnetii bacterium is the pathogen that causes Q fever. The bacterium is transmitted to animals via ticks, and manure, air, dead infected animals, etc. and can cause infection in domestic animals, wild animals, and humans. Xinjiang, the provincial-level administrative region with the largest land area in China, has many endemic tick species. The infection rate of C. burnetii in ticks in Xinjiang border areas has not been studied in detail. RESULTS: For the current study, 1507 ticks were collected from livestock at 22 sampling sites in ten border regions of the Xinjiang Uygur Autonomous region from 2018 to 2019. C. burnetii was detected in 205/348 (58.91%) Dermacentor nuttalli; in 110/146 (75.34%) D. pavlovskyi; in 66/80 (82.50%) D. silvarum; in 15/32 (46.90%) D. niveus; in 28/132 (21.21%) Hyalomma rufipes; in 24/25 (96.00%) H. anatolicum; in 219/312 (70.19%) H. asiaticum; in 252/338 (74.56%) Rhipicephalus sanguineus; and in 54/92 (58.70%) Haemaphysalis punctata. Among these samples, C. burnetii was detected in D. pavlovskyi for the first time. The infection rate of Rhipicephalus was 74.56% (252/338), which was the highest among the four tick genera sampled, whereas the infection rate of H. anatolicum was 96% (24/25), which was the highest among the nine tick species sampled. A sequence analysis indicated that 63 16S rRNA sequences could be found in four newly established genotypes: MT498683.1 (n = 18), MT498684.1 (n = 33), MT498685.1 (n = 6), and MT498686.1 (n = 6). CONCLUSIONS: This study indicates that MT498684.1 might represent the main C. burnetii genotype in the ticks in Xinjiang because it was detected in eight of the tick species studied. The high infection rate of C. burnetii detected in the ticks found in domestic animals may indicate a high likelihood of Q fever infection in both domestic animals and humans.

16.
J Phys Chem Lett ; : 7782-7789, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32856921

RESUMO

The past decade has witnessed the burgeoning discovery of a variety of topological states of matter with distinct nontrivial band topologies. Thus far, most materials that have been studied possess two-dimensional or three-dimensional electronic structures, with only a few exceptions that host quasi-one-dimensional (quasi-1D) topological electronic properties. Here we present clear-cut evidence for Dirac Fermions in the quasi-1D telluride TaNiTe5. We show that its transport behaviors are highly anisotropic, and we observe nontrivial Berry phases via quantum oscillation measurements. The nontrivial band topology is further corroborated by first-principles calculations. Our results may help to guide the future quest for topological states in this new family of quasi-1D ternary chalcogenides.

17.
Sci Rep ; 10(1): 12957, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737391

RESUMO

Transition-metal dichalcogenides (TMDs) offer an ideal platform to experimentally realize Dirac fermions. However, typically these exotic quasiparticles are located far away from the Fermi level, limiting the contribution of Dirac-like carriers to the transport properties. Here we show that NiTe2 hosts both bulk Type-II Dirac points and topological surface states. The underlying mechanism is shared with other TMDs and based on the generic topological character of the Te p-orbital manifold. However, unique to NiTe2, a significant contribution of Ni d orbital states shifts the energy of the Type-II Dirac point close to the Fermi level. In addition, one of the topological surface states intersects the Fermi energy and exhibits a remarkably large spin splitting of 120 meV. Our results establish NiTe2 as an exciting candidate for next-generation spintronics devices.

18.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(3): 399-404, 2020 Jun 30.
Artigo em Chinês | MEDLINE | ID: mdl-32616139

RESUMO

Oral cancer is a common and deadly malignancy.While multidisciplinary treatment(mainly surgery)has been applied in the treatment of cancer treatment,early diagnosis and complete removal of the primary lesion are essential for a better prognosis.Raman spectroscopy is an optical technique that detects inelastic scattered light generated by the interaction of light and matter.It can detect the vibrational spectra of biochemical and biomolecular structures and tissue conformations,and can provide the "molecular fingerprint" for cells,tissues,and biological fluids.With the development of related technologies and optical instruments,Raman spectroscopy has been widely applied in medical fields.This article reviews the research advances and application of Raman spectroscopy in the diagnosis of oral cancer.


Assuntos
Neoplasias Bucais , Análise Espectral Raman , Humanos
19.
Exp Parasitol ; 217: 107955, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32649953

RESUMO

Nicotiana tabacum, Stemona japonica, and Cnidium monnieri are common plants that are widely used for their anti-parasitic properties. The purpose of this study was to evaluate the acaricidal activity of extracts from these plants against the brown dog tick, Rhipicephalus sanguineus. A composition analysis of crude extracts by GC-MS was conducted to discover compounds with acaricidal effects. The toxicity of extraction against the engorged nymphs of R. sanguineus was evaluated by an immersion test. The results showed that the crude extracts of S. japonica and C. monnieri in varying ratios, concentrations, and from different extraction methods, had a killing effect on R. sanguineus. Lethality reached 76.67% ± 0.04410 when using a 1:1 extract of S. japonica:C. monnieri in 75% ethanol with ultrasonic extraction; the crude extract was determined at a concentration of 0.5 g/mL. GC-MS results showed that osthole and 5-hydroxymethylfurfural (5-HMF) are the main components of the extract. These results suggested that ultrasound-assisted extraction (UAE) extracts contained acaricidal components acting against R. sanguineus, which may result in the development of effective extracts of S. japonica and C. monnieri as a source of low-toxicity, plant-based, natural acaricidal drugs.


Assuntos
Cnidium/química , Extratos Vegetais/farmacologia , Rhipicephalus sanguineus/efeitos dos fármacos , Stemonaceae/química , Controle de Ácaros e Carrapatos/métodos , Animais , Bioensaio , Cumarínicos/análise , Cumarínicos/farmacologia , Furaldeído/análogos & derivados , Furaldeído/análise , Furaldeído/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Muda/efeitos dos fármacos , Ninfa/efeitos dos fármacos , Extratos Vegetais/química , Coelhos , Tabaco/química
20.
Sci Total Environ ; 736: 139587, 2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32492611

RESUMO

Permafrost play an important role in regulating global climate system. We analyzed the gross primary productivity (GPP), net primary productivity (NPP), and evapotranspiration (ET) derived from MODIS and three earth system models participated in the Coupled Model Inter-comparison Project Phase 6 (CMIP6) in the Asian permafrost region. The water use efficiency (WUE) was further computed. The simulated GPP, NPP, and ET show slightly increasing trends during historical period (1900-2014) and strong increasing trends in projection period (2015-2100), and projected impacts of climate change on all variables are greater under high-emission scenarios than low-emission scenarios. Further analysis revealed higher increases in GPP and NPP than that of ET, indicating that vegetation carbon sequestration governs the growing WUE under historical and projected periods in this region. The GPP, NPP and ET showed higher changing rates in western, central and southeast areas of this region, and WUE (WUEGPP, and WUENPP) shows the similar spatial pattern. Compared to MODIS-derived GPP, NPP, and ET during 2000-2014, Earth system models yield the best estimates for NPP, while slight underestimations for GPP and ET, and thus slight overestimations for WUEGPP and WUENPP. This study highlights the predominant role of vegetation activity in regulating regional WUE in Asian permafrost region under future climate change. Vegetation domination of the growing water use efficiency implies that the permafrost region may continue acting efficiently in sequestrating atmospheric carbon in terms of water consumption throughout the 21st century.


Assuntos
Pergelissolo , Ciclo do Carbono , Mudança Climática , Ecossistema , Modelos Teóricos , Água
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