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1.
Nat Commun ; 10(1): 5230, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31745089

RESUMO

The Hengduan Mountains (HDM) biodiversity hotspot exhibits exceptional alpine plant diversity. Here, we investigate factors driving intraspecific divergence within a HDM alpine species Salix brachista (Cushion willow), a common component of subnival assemblages. We produce a high-quality genome assembly for this species and characterize its genetic diversity, population structure and pattern of evolution by resequencing individuals collected across its distribution. We detect population divergence that has been shaped by a landscape of isolated sky island-like habitats displaying strong environmental heterogeneity across elevational gradients, combined with population size fluctuations that have occurred since approximately the late Miocene. These factors are likely important drivers of intraspecific divergence within Cushion willow and possibly other alpine plants with a similar distribution. Since intraspecific divergence is often the first step toward speciation, the same factors can be important contributors to the high alpine species diversity in the HDM.

2.
Dev Growth Differ ; 61(7-8): 410-418, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31608440

RESUMO

Macular fibrosis is a vital obstacle of vision acuity improvement of age-related macular degeneration patients. This study was to investigate the effects of interleukin 2 (IL-2) on epithelial-mesenchymal transition (EMT), extracellular matrix (ECM) synthesis and transforming growth factor ß2 (TGF-ß2) expression in retinal pigment epithelial (RPE) cells. 10 µg/L IL-2 was used to induce fibrosis in RPE cells for various times. Western blot was used to detect the EMT marker α-smooth muscle actin (α-SMA), ECM markers fibronectin (Fn) and type 1 collagen (COL-1), TGF-ß2, and the activation of the JAK/STAT3 and NF-κB signaling pathway. Furthermore, JAK/STAT3 and NF-κB signaling pathways were specifically blocked by WP1066 or BAY11-7082, respectively, and the expression of α-SMA, COL-1, Fn and TGF-ß2 protein were detected. Wound healing and Transwell assays were used to measure cell migration ability of IL-2 with or without WP1066 or BAY11-7082. After induction of IL-2, the expressions of Fn, COL-1, TGF-ß2 protein were significantly increased, and this effect was correlated with IL-2 treatment duration, while α-SMA protein expression did not change significantly. Both WP1066 and BAY11-7082 could effectively downregulate the expression of Fn, COL-1 and TGF-ß2 induced by IL-2. What's more, both NF-κB and JAK/STAT3 inhibitors could suppress the activation of the other signaling pathway. Additionally, JAK/STAT3 inhibitor WP1066 and NF-κB inhibitor BAY 11-7082 could obviously decrease RPE cells migration capability induced by IL-2. IL-2 promotes cell migration, ECM synthesis and TGF-ß2 expression in RPE cells via JAK/STAT3 and NF-κB signaling pathways, which may play an important role in proliferative vitreoretinopathy.

3.
Int J Med Microbiol ; 309(8): 151340, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31494039

RESUMO

Chlamydia pneumoniae (C. pneumoniae) infection is associated with the initiation and progression of atherosclerosis. The migration of vascular smooth muscle cell (VSMC) from the media to the intima is a key event in the development of atherosclerosis. Interleukin-17C (IL-17C) could enhance cell migration ability. The aim of our study is to investigate the role of IL-17C in C. pneumoniae infection-promoted VSMC migration, thereby possibly accelerating atherosclerosis. We firstly demonstrated that C. pneumoniae infection significantly increased IL-17C expression in VSMCs in the atherosclerotic lesion area from ApoE deficient mice. Our in vitro study further showed that IL-17C is required for C. pneumoniae infection-promoted VSMC migration, and its expression could be regulated by c-Fos through phosphorylating extracellular signal-regulated kinase (ERK). Unexpectedly, in the present study, we also found that IL-17C is critical for C. pneumoniae infection-induced c-Fos activation. c-Fos expression and activation induced by the exposure to recombinant IL-17C were markedly suppressed in the presence of the ERK inhibitor PD98059. These results suggest a possible positive feedback between c-Fos and IL-17C after C. pneumoniae infection. Taken together, our results indicate that C. pneumoniae infection promotes VSMC migration via c-Fos/IL-17C signaling.

4.
Oncotarget ; 9(57): 30962-30978, 2018 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-30123420

RESUMO

Neuronal plasticity occurs in associative memory. Associative memory cells are recruited for the integration and storage of associated signals. The coordinated refinements and interactions of associative memory cells including glutamatergic and GABAergic neurons remain elusive, which we have examined in a mouse model of associative learning. Paired olfaction, tail and whisker stimulations lead to odorant-induced and tail-induced whisker motions alongside whisker-induced whisker motion. In mice that show this cross-modal associative memory, barrel cortical glutamatergic and GABAergic neurons are recruited to encode the newly learned odor and tail signals alongside the innate whisker signal. These glutamatergic neurons are functionally upregulated, and GABAergic neurons are refined in a homeostatic manner. The mutual innervations between these glutamatergic and GABAergic neurons are upregulated. Therefore, the co-activations of sensory cortices by pairing the input signals recruit their glutamatergic and GABAergic neurons to be associative memory cells, which undergo coordinated refinement among glutamatergic and GABAergic neurons as well as homeostatic plasticity among subcellular compartments in order to drive these cells toward the optimal state for the integrative storage of associated signals.

5.
Biochem Biophys Res Commun ; 497(2): 742-748, 2018 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-29462613

RESUMO

Migration of monocytes into the subendothelial layer of the intima is one of the critical events in early atherosclerosis. Chlamydia pneumoniae (C. pneumoniae) infection has been shown to promote monocyte transendothelial migration (TEM). However, the exact mechanisms have not yet been fully clarified. In this study, we tested the hypothesis that C. pneumoniae infection increases vascular endothelial cell (VEC) permeability and subsequent monocyte TEM through stimulating the tyrosine phosphorylation of vascular endothelial-cadherin (VE-cadherin). Here, we demonstrated that C. pneumoniae infection promoted monocyte TEM in a TEM assay possibly by increasing the permeability of a VEC line EA.hy926 cell as assessed by measuring the passage of FITC-BSA across a VEC monolayer. Subsequently, Western blot analysis showed that C. pneumoniae infection induced VE-cadherin internalization. Our further data revealed that Src-mediated VE-cadherin phosphorylation at Tyr658 was involved in C. pneumoniae infection-induced internalization of VE-cadherin, VEC hyperpermeability and monocyte TEM. Taken together, our data indicate that C. pneumoniae infection promotes monocyte TEM by increasing VEC permeability via the tyrosine phosphorylation and internalization of VE-cadherin in VECs.


Assuntos
Antígenos CD/metabolismo , Caderinas/metabolismo , Permeabilidade Capilar , Infecções por Chlamydophila/metabolismo , Chlamydophila pneumoniae/fisiologia , Monócitos/microbiologia , Migração Transendotelial e Transepitelial , Células Cultivadas , Infecções por Chlamydophila/microbiologia , Infecções por Chlamydophila/patologia , Endotélio Vascular/metabolismo , Endotélio Vascular/microbiologia , Endotélio Vascular/patologia , Interações Hospedeiro-Patógeno , Humanos , Monócitos/citologia , Monócitos/patologia , Fosforilação
6.
ACS Nano ; 11(12): 12385-12391, 2017 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-29140678

RESUMO

Superhydrophobic carbon nanotube (CNT) films have demonstrated many fascinating performances in versatile applications, especially for those involving solid/liquid interfacial processes, because of their ability to affect the material/energy transfer at interfaces. Thus, developing superhydrophobic CNTs has attracted extensive research interests in the past decades, and it could be achieved either by surface coating of low-free energy materials or by constructing micro/nanohierarchical structures via various complicated processes. So far, developing a simple approach to fabricate stable superhydrophobic CNTs remains a challenge because the capillary force induced coalescence frequently happens when interacting with liquid. Herein, drawing inspirations from the lotus leaf, we proposed a simple one-step chemical vapor deposition approach with programmable controlled gas flow to directly fabricate a CNT film with rather stable superhydrophobicity, which can effectively prevent even small water droplets from permeating into the film. The robust superhydrophobicity was attributable to typical lotus-leaf-like micro/nanoscale hierarchical surface structures of the CNT film, where many microscale clusters composed of entangled nanotubes randomly protrude out of the under-layer aligned nanotubes. Consequently, dual-scale air pockets were trapped within each microscale CNT cluster and between, which could largely reduce the liquid/solid interface, leading to a Cassie state. Moreover, the superhydrophobicity of the CNT film showed excellent durability after long time exposure to air and even to corrosive liquids with a wide range of pH values. We envision that the approach developed is advantageous for versatile physicochemical interfacial processes, such as drag reduction, electrochemical catalysis, anti-icing, and biosensors.

7.
J Plant Res ; 130(6): 989-997, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28642987

RESUMO

Chromosome number and genome size are important cytological characters that significantly influence various organismal traits. We investigated chromosome number and genome size variation in 73 accessions belonging to four Colocasia species from China. Five different chromosome counts (2n = 26, 28, 38, 42, and 56) were found, the largest one representing a new record in Colocasia. The basic chromosome numbers are x = 13, 14, and 19, corresponding to 2x, 3x, and 4x cytotypes. Yunnan Province, China is considered the center of Colocasia polyploid origin. The 2C values in our accessions ranged from 3.29 pg in C. gigantea to 12.51 pg in C. esculenta. All species exhibit inter- and intraspecific chromosomal variation. Differences in DNA content among the Colocasia species seem to have occurred by chromosomal gain under similar habitats. Polyploidization also obviously contributes to 2C value variation.


Assuntos
Cromossomos de Plantas/genética , Colocasia/genética , Variação Genética , Tamanho do Genoma , Genoma de Planta/genética , China , Geografia , Cariótipo , Fenótipo , Folhas de Planta/genética , Raízes de Plantas/genética , Poliploidia
8.
Oncotarget ; 8(22): 35933-35945, 2017 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-28415589

RESUMO

BACKGROUND: Major depression, persistent low mood, is one of common psychiatric diseases. Chronic stressful life is believed to be a major risk factor that leads to dysfunctions of the limbic system. However, a large number of the individuals with experiencing chronic stress do not suffer from major depression, called as resilience. Endogenous mechanisms underlying neuronal invulnerability to chronic stress versus major depression are largely unknown. As GABAergic neurons are vulnerable to chronic stress and their impairments is associated with major depression, we have examined whether the invulnerability of GABAergic neurons in the limbic system is involved in resilience. RESULTS: GABAergic neurons in the nucleus accumbens from depression-like mice induced by chronic unpredictable mild stress appear the decreases in their GABA release, spiking capability and excitatory input reception, compared with those in resilience mice. The levels of decarboxylase and vesicular GABA transporters decrease in depression-like mice, but not resilience. MATERIALS AND METHODS: Mice were treated by chronic unpredictable mild stress for three weeks. Depression-like behaviors or resilience was confirmed by seeing whether their behaviors change significantly in sucrose preference, Y-maze and forced swimming tests. Mice from controls as well as depression and resilience in response to chronic unpredictable mild stress were studied in terms of GABAergic neuron activity in the nucleus accumbens by cell electrophysiology and protein chemistry. CONCLUSIONS: The impairment of GABAergic neurons in the nucleus accumbens is associated with major depression. The invulnerability of GABAergic neurons to chronic stress may be one of cellular mechanisms for the resilience to chronic stress.


Assuntos
Transtorno Depressivo Maior/etiologia , Transtorno Depressivo Maior/metabolismo , Neurônios GABAérgicos/metabolismo , Núcleo Accumbens/metabolismo , Resiliência Psicológica , Estresse Fisiológico , Animais , Comportamento Animal , Transtorno Depressivo Maior/psicologia , Modelos Animais de Doenças , Masculino , Camundongos , Modelos Biológicos , Transmissão Sináptica
9.
PLoS One ; 11(11): e0166535, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27861545

RESUMO

BACKGROUND: Stressful life leads to mood disorders. Chronic mild stress is presumably major etiology for depression, and acute severe stress leads to anxiety. These stressful situations may impair hypothalamus-pituitary-adrenal axis and in turn induce synapse dysfunction. However, it remains elusive how the stress hormones mess up subcellular compartments and interactions between excitatory and inhibitory neurons, which we have investigated in mouse amygdala, a structure related to emotional states. METHODS AND RESULTS: Dexamethasone was chronically given by intraperitoneal injection once a day for one week or was acutely washed into the brain slices. The neuronal spikes and synaptic transmission were recorded by whole-cell patching in amygdala neurons of brain slices. The chronic or acute administration of dexamethasone downregulates glutamate release as well as upregulates GABA release and GABAergic neuron spiking. The chronic administration of dexamethasone also enhances the responsiveness of GABA receptors. CONCLUSION: The upregulation of GABAergic neurons and the downregulation of glutamatergic neurons by glucocorticoid impair their balance in the amygdala, which leads to emotional disorders during stress.


Assuntos
Tonsila do Cerebelo/citologia , Tonsila do Cerebelo/fisiologia , Neurônios GABAérgicos/efeitos dos fármacos , Neurônios GABAérgicos/fisiologia , Glucocorticoides/farmacologia , Ácido Glutâmico/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Tonsila do Cerebelo/efeitos dos fármacos , Animais , Dexametasona/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Camundongos , Receptores de GABA/metabolismo , Ácido gama-Aminobutírico/metabolismo
10.
Plant Divers ; 38(4): 190-193, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30159464

RESUMO

Fresh plant material is usually used for genome size estimation by flow cytometry (FCM). Lack of fresh material is cited as one of the main reasons for the dearth of studies on plants from remote locations. Genome sizes in fresh versus desiccated tissue of 16 Ophiopogoneae species and five model plant species were estimated. Our results indicated that desiccated tissue was suitable for genome size estimation; this method enables broader geographic sampling of plants when fresh tissue collection is not feasible. To be useful, after dessication the Ophiopogoneae sample should be green without brown or yellow markings; it should be stored in deep freezer at -80 °C, and the storage time should be no more than 6 months.

11.
Case Rep Anesthesiol ; 2014: 718690, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24757571

RESUMO

Paraplegia is a rare postoperative complication. We present a case of acute paraplegia after elective gastrectomy surgery because of cervical disc herniation. The 73-year-old man has the medical history of cervical spondylitis with only symptom of temporary pain in neck and shoulder. Although the patient's neck was cautiously preserved by using the Discopo, an acute paraplegia emerged at about 10 hours after the operation. Severe compression of the spinal cord by herniation of the C4-C5 cervical disc was diagnosed and emergency surgical decompression was performed immediately. Unfortunately the patient showed limited improvement in neurologic deficits even after 11 months.

12.
FEBS J ; 280(16): 3920-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23773620

RESUMO

Adiponectin is an adipocyte hormone that is predominantly secreted by adipocytes, and has important roles in glucose and lipid homeostasis. Recent studies have shown that adiponectin is also involved in the regulation of many endocrine organs, such as the ovary, adrenal gland, and pituitary. However, its biological role in male testes is largely unexplored. The present findings demonstrate the presence of adeponectin receptors (adiponectin receptor 1 and adiponectin receptor 2) in TM3 cells derived from mouse Leydig cells. Proinflammatory cytokine treatment significantly downregulated mRNA and protein levels of adiponectin receptor 1 and adiponectin receptor 2. However, adiponectin pretreatment successfully inhibited the signaling pathway mediated by proinflammatory cytokines. At the molecular level, we provide compelling evidence that adeponectin achieves this by suppressing nuclear factor-κB activation through promotion of AMP-activated protein kinase phosphorylation. Thus, our data clearly indicate that adiponectin plays a protective role in Leydig cells through its anti-inflammatory actions.


Assuntos
Adiponectina/metabolismo , Citocinas/antagonistas & inibidores , Regulação para Baixo , Células Intersticiais do Testículo/metabolismo , NF-kappa B/antagonistas & inibidores , Receptores de Adiponectina/metabolismo , Transdução de Sinais , 3-Hidroxiesteroide Desidrogenases/antagonistas & inibidores , 3-Hidroxiesteroide Desidrogenases/química , 3-Hidroxiesteroide Desidrogenases/genética , 3-Hidroxiesteroide Desidrogenases/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Linhagem Celular , Ciclo-Oxigenase 2/química , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Inativação Gênica , Células Intersticiais do Testículo/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/química , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Fosfoproteínas/agonistas , Fosfoproteínas/antagonistas & inibidores , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fosforilação , Processamento de Proteína Pós-Traducional , Receptores de Adiponectina/antagonistas & inibidores , Receptores de Adiponectina/genética , Regulação para Cima
13.
J Plant Res ; 126(5): 597-604, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23508340

RESUMO

Chromosome numbers and karyotypes of 26 Ophiopogon species, 2 Liriope species and 5 Peliosanthes species of the family Liliaceae from Southwest China, were investigated. The study revealed a detailed picture of chromosome features and their pattern of karyotype variation in Ophiopogoneae. Karyotype asymmetry in different species and different populations of the same species varied greatly due to different locality conditions. Our analyses may support the separately monophyly of Ophiopogon, Liriope and Peliosanthes.


Assuntos
Cromossomos de Plantas/genética , Genoma de Planta/genética , Cariótipo , Liliaceae/genética , Evolução Biológica , China , Cariotipagem , Poliploidia
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