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1.
Artigo em Inglês | MEDLINE | ID: mdl-38918087

RESUMO

Tracheal bronchus is a rare congenital tracheal abnormality that generally refers to the right upper lobe bronchus of the lung that originates from the trachea. Tracheal bronchus is usually asymptomatic and is often accidentally detected by fiberoptic bronchoscopy or computed tomography for other conditions. Depending on the location of the tracheal bronchial opening and possible anatomical variations, the management of 1-lung ventilation in patients with tracheal bronchus is a significant challenge for anesthesiologists. To provide a reference for anesthesiologists to better manage anesthesia in such patients, we review the pathophysiology, definition, and Conacher classification of tracheal bronchus and then discuss the diagnosis of tracheal bronchus and management of 1-lung ventilation during anesthesia according to the Conacher classification.

2.
Sci Rep ; 10(1): 6543, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32300144

RESUMO

It is well recognized that the zonal shift in the South Asian High (SAH) has pronounced influences on weather and climate anomalies over surrounding and teleconnected regions. Hence, it is of great importance to investigate the factors related to the interannual variation in the zonal location of the SAH. This study indicates that the anomalous atmospheric apparent heat source () around East Europe has a close relationship with the interannual variation in the SAH zonal shift during boreal summer. In particular, when above (below) normal exists, the SAH tends to shift westward (eastward). Above-normal over East Europe can trigger an eastward propagating wave train along the subtropical jet stream, resembling the negative phase of the Silk Road teleconnection pattern, with positive geopotential height anomalies around the Iranian Plateau and Northeast Asia and negative anomalies around East Europe and the Tibetan Plateau, which could lead to a westward shift in the SAH. Our model experiments confirm that anomalous around East Europe can exert pronounced impacts on the zonal shift in the SAH by inducing an eastward propagating atmospheric wave train.

3.
Adv Mater ; 29(9)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28008660

RESUMO

Azobenzene-containing cross-linked liquid crystal polymer films without hydrophilic groups exhibit dual-responsivity to humidity and UV light. The films realize not only a series of large and sophisticated contactless motions by utilizing moisture, including an inchworm walk, and tumbling locomotion, but also dual-mode actuation that can be applied in flexible electronics.

4.
ACS Appl Mater Interfaces ; 9(1): 782-789, 2017 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-28001030

RESUMO

Two types of novel reactive linear liquid crystal polymers (LLCPs) with different azotolene concentrations have been synthesized and processed into films and fibers by solution and melting processing methods. Then, the LLCPs in the obtained monodomain fiber and polydomain film were easily cross-linked with difunctional primary amines. The resulted cross-linked liquid crystal polymers (CLCPs) underwent reversible photoinduced bending and unbending behaviors in response to 445 and 530 nm visible light at room temperature, respectively. The post-cross-linking method provides a facile way to prepare the CLCP films and fibers with different shapes from LLCPs, which can be processed by traditional melting and solution methods.

5.
Nature ; 537(7619): 179-84, 2016 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-27604946

RESUMO

The manipulation of small amounts of liquids has applications ranging from biomedical devices to liquid transfer. Direct light-driven manipulation of liquids, especially when triggered by light-induced capillary forces, is of particular interest because light can provide contactless spatial and temporal control. However, existing light-driven technologies suffer from an inherent limitation in that liquid motion is strongly resisted by the effect of contact-line pinning. Here we report a strategy to manipulate fluid slugs by photo-induced asymmetric deformation of tubular microactuators, which induces capillary forces for liquid propulsion. Microactuators with various shapes (straight, 'Y'-shaped, serpentine and helical) are fabricated from a mechanically robust linear liquid crystal polymer. These microactuators are able to exert photocontrol of a wide diversity of liquids over a long distance with controllable velocity and direction, and hence to mix multiphase liquids, to combine liquids and even to make liquids run uphill. We anticipate that this photodeformable microactuator will find use in micro-reactors, in laboratory-on-a-chip settings and in micro-optomechanical systems.

6.
Neuroimage ; 89: 226-34, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23618602

RESUMO

The seven-factor biopsychosocial model of personality distinguished four biologically based temperaments and three psychosocially based characters. Previous studies have suggested that the four temperaments-novelty seeking (NS), reward dependence (RD), harm avoidance (HA), and persistence (P)-have their respective neurobiological correlates, especially in the striatum-connected subcortical and cortical networks. However, few studies have investigated their neurobiological basis in the form of fiber connectivity between brain regions. This study correlated temperaments with fiber connectivity between the striatum and subcortical and cortical hub regions in a sample of 50 Chinese adult males. Generally consistent with our hypotheses, results showed that: (1) NS was positively correlated with fiber connectivity from the medial and lateral orbitofrontal cortex (mOFC, lOFC) and amygdala to the striatum; (2) RD was positively correlated with fiber connectivity from the mOFC, posterior cingulate cortex/retrosplenial cortex (PCC), hippocampus, and amygdala to the striatum; (3) HA was positively linked to fiber connectivity from the dorsolateral prefrontal cortex (dlPFC) and PCC to the striatum; and (4) P was positively linked to fiber connectivity from the mOFC to the striatum. These results extended the research on the neurobiological basis of temperaments by identifying their anatomical fiber connectivity correlates within the subcortical-cortical neural networks.


Assuntos
Encéfalo/anatomia & histologia , Córtex Cerebral/anatomia & histologia , Corpo Estriado/anatomia & histologia , Rede Nervosa/anatomia & histologia , Temperamento , Adulto , Tonsila do Cerebelo/anatomia & histologia , Povo Asiático , Imagem de Tensor de Difusão , Humanos , Masculino , Fibras Nervosas Mielinizadas , Vias Neurais , Adulto Jovem
7.
Adv Mater ; 26(11): 1782-7, 2014 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-24375918

RESUMO

An azobenzene-derived surfactant behaves as a "smart" molecule. Not only is it used as the structure-directing agent to synthesize unique mesoporous silica nanospheres, but it can also be quickly released from the silica framework with UV light and subsequently recycled.

8.
Toxicol Lett ; 224(1): 130-40, 2014 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-24157283

RESUMO

Arsenic (As), a well-known high toxic metal, is an important environmental and industrial contaminant, and it induces oxidative stress, which causes many adverse health effects and diseases in humans, particularly in inorganic As (iAs) more harmful than organic As. Recently, epidemiological studies have suggested a possible relationship between iAs exposure and neurodegenerative disease development. However, the toxicological effects and underlying mechanisms of iAs-induced neuronal cell injuries are mostly unknown. The present study demonstrated that iAs significantly decreased cell viability and induced apoptosis in Neuro-2a cells. iAs also increased oxidative stress damage (production of malondialdehyde (MDA) and ROS, and reduction of Nrf2 and thioredoxin protein expression) and induced several features of mitochondria-dependent apoptotic signals, including: mitochondrial dysfunction, the activations of PARP and caspase cascades, and the increase in caspase-3 activity. Pretreatment with the antioxidant N-acetylcysteine (NAC) effectively reversed these iAs-induced responses. iAs also increased the phosphorylation of JNK and ERK1/2, but did not that p38-MAPK, in treated Neuro-2a cells. NAC and the specific JNK inhibitor (SP600125) and ERK1/2 inhibitor (PD98059) abrogated iAs-induced cell cytotoxicity, caspase-3/-7 activity, and JNK and ERK1/2 activation. Additionally, exposure of Neuro-2a cells to iAs triggered endoplasmic reticulum (ER) stress identified through several key molecules (GRP 78, CHOP, XBP-1, and caspase-12), which was prevented by NAC. Transfection with GRP 78- and CHOP-specific si-RNA dramatically suppressed GRP 78 and CHOP expression, respectively, and attenuated the activations of caspase-12, -7, and -3 in iAs-exposed cells. Therefore, these results indicate that iAs induces ROS causing neuronal cell death via both JNK/ERK-mediated mitochondria-dependent and GRP 78/CHOP-triggered apoptosis pathways.


Assuntos
Apoptose/efeitos dos fármacos , Arsênio/toxicidade , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Proteínas de Choque Térmico/fisiologia , Proteínas Quinases JNK Ativadas por Mitógeno/fisiologia , Mitocôndrias/fisiologia , Neurônios/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição CHOP/fisiologia , Animais , Chaperona BiP do Retículo Endoplasmático , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos
9.
Mol Med Rep ; 7(3): 831-5, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23358592

RESUMO

The present study was undertaken to confirm whether sulodexide aleviates neointimal hyperplasia by regulating angiopoietin/Tie in a rat femoral arteriovenous fistula (AVF) model. Sprague Dawley rats were divided into four groups: sham, model, treatment and treatment control. An arteriovenous shunt model was created in the model and treatment groups. Sulodexide was subcutaneously administered (10 mg/kg/day) 6 times per week for 8 weeks in the treatment and treatment control groups. Histology and immunofluorescence were analyzed and the protein expression of angiopoietin­1, angiopoietin­2, Tie­2, p­ERK and total­ERK were tested by ELISA and/or western blotting after 8 weeks. HE staining revealed that sulodexide was able to partially alleviate intimal hyperplasia of remodeled veins in the AVF model. Additionally, sulodexide was able to decrease angiopoietin­2 and Tie­2 expression while increasing angiopoietin­1 expression in AVF tissue. Sulodexide was also able to decrease ERK phosphorylation which was increased in the model. Serum levels of soluble Tie-2 (sTie­2) were also significantly decreased by sulodexide compared with the model. Immunofluorescent analysis also confirmed that sulodexide was able to decrease angiopoietin­2 expression, possibly partially by inhibiting endothelial cell proliferation. Sulodexide may alleviate venous intimal hyperplasia by regulating the angiopoietin/Tie system, which may play a significant role in assisting remodeled veins to cope with their new biomechanical environment, but whether the angiopoietin/Tie system is beneficial or not requires further study.


Assuntos
Angiopoietina-2/metabolismo , Fibrinolíticos/farmacologia , Glicosaminoglicanos/farmacologia , Túnica Íntima/efeitos dos fármacos , Angiopoietina-1/sangue , Angiopoietina-2/antagonistas & inibidores , Angiopoietina-2/sangue , Animais , Fístula Arteriovenosa/metabolismo , Fístula Arteriovenosa/patologia , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Hiperplasia , Masculino , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptor TIE-2/sangue , Túnica Íntima/patologia , Regulação para Cima/efeitos dos fármacos
10.
PLoS One ; 7(10): e47019, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23071701

RESUMO

Humans demonstrate an inherent bias towards making maladaptive decisions, as shown by a phenomenon known as the gambler's fallacy (GF). The GF has been traditionally considered as a heuristic bias supported by the fast and automatic intuition system, which can be overcome by the reasoning system. The present study examined an intriguing hypothesis, based on emerging evidence from neuroscience research, that the GF might be attributed to a weak affective but strong cognitive decision making mechanism. With data from a large sample of college students, we found that individuals' use of the GF strategy was positively correlated with their general intelligence and executive function, such as working memory and conflict resolution, but negatively correlated with their affective decision making capacities, as measured by the Iowa Gambling Task. Our result provides a novel insight into the mechanisms underlying the GF, which highlights the significant role of affective mechanisms in adaptive decision-making.


Assuntos
Cognição , Tomada de Decisões , Jogo de Azar/psicologia , Função Executiva , Feminino , Humanos , Testes de Inteligência , Intuição , Masculino , Experimentação Humana não Terapêutica , Adulto Jovem
11.
Sci Rep ; 2: 677, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22997551

RESUMO

Both genetic and environmental factors have been shown to influence decision making, but their relative contributions and interactions are not well understood. The present study aimed to reveal possible gene-environment interactions on decision making in a large healthy sample. Specifically, we examined how the frequently studied COMT Val(158)Met polymorphism interacted with an environmental risk factor (i.e., stressful life events) and a protective factor (i.e., parental warmth) to influence affective decision making as measured by the Iowa Gambling Task. We found that stressful life events acted as a risk factor for poor IGT performance (i.e., high reward sensitivity) among Met carriers, whereas parental warmth acted as a protective factor for good IGT performance (i.e., higher IGT score) among Val/Val homozygotes. These results shed some new light on gene-environment interactions in decision making, which could potentially help us understand the underlying etiology of several psychiatric disorders associated with decision making impairment.


Assuntos
Catecol O-Metiltransferase/genética , Tomada de Decisões , Interação Gene-Ambiente , Acontecimentos que Mudam a Vida , Relações Pais-Filho , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Substituição de Aminoácidos , Análise de Variância , Feminino , Jogo de Azar , Jogos Experimentais , Estudos de Associação Genética , Humanos , Masculino , Fatores de Risco , Estatísticas não Paramétricas , Adulto Jovem
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