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1.
Ann Palliat Med ; 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32692241

RESUMO

BACKGROUND: To analyze the clinical and infectious characteristics of new coronavirus pneumonia with diagnosed and suspected cases in the Second Hospital of WISCO(Wuhan Iron and Steel Company) of Qingshan District, Wuhan City, and further enhance the understanding of new coronavirus pneumonia. METHODS: According to the fifth and sixth editions of the new coronavirus pneumonia diagnosis and treatment plan issued by the National Health Commission of the People's Republic of China and National Administration of Traditional Chinese Medicine, we carried out the case analysis and infectious disease investigation and research on the confirmed and suspected cases of new coronavirus pneumonia admitted to the second-floor ward of the hospital from January 28th, 2020, to February 26th, 2020. RESULTS: From January 28th, 2020 to February 26th, 2020, 83 patients were admitted, 40 were cured, and 7 died. Before February 13th, 69 patients were admitted, including 22 confirmed patients and 47 suspected patients. After February 13th, the data of newly hospitalized suspected patients decreased to 2 people. The average time from onset to diagnosis was 5.38 days. About 57.1% of the confirmed patients were isolated at home before admission, and 53.2% of the suspected patients were isolated by hospital observation before admission. The proportion of fever and other clinical symptoms was 81.8%, 65.5% of the patients had the fastest heart rate of 90-120 rpm, and 11 of the patients had severe/critical illness, accounting for 20%. The count of leukocytes, neutrophils, and C-reactive proteins (CRPs) in severe patients was higher than those in light patients (P<0.05), and the count of lymphocytes was lower than that in mild patients (P=0.016). CONCLUSIONS: The novel coronavirus pneumonia in Qingshan District of Wuhan in February was diagnosed promptly, controlled,and treated effectively. The combination of traditional Chinese and western medicine in the treatment of new coronavirus pneumonia might help patients.

2.
Minerva Anestesiol ; 86(8): 853-860, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32449338

RESUMO

INTRODUCTION: Delirium is an acute and fluctuating change in cognition, attention and consciousness, defined as an acute neuropsychiatric syndrome, but mechanism is extremely complex and still not well understood. Recently, the S100 calcium-binding protein B protein (S100ß) has received attention in the biomarker research area of delirium. This meta-analysis was designed to investigate the relationship between S100ß levels and delirium. EVIDENCE ACQUISITION: We conducted a systematic literature search of MEDLINE (via PubMed search engine), Ovid, EMBASE, and Cochrane Library electronic databases for case-control studies measuring S100ß levels from delirium and no delirium controls. Extracted data were analyzed with STATA. The standardized mean difference (SMD) and the 95% confidence interval (95% CI) were calculated using a random effect model. EVIDENCE SYNTHESIS: We identified ten eligible studies including 1739 patients. The pooled SMD showed significant difference in S100ß between delirium patients and control (SMD: 0.88; 95% CI: 0.31 to 1.46), but there was high heterogeneity (I2: 95.9%; P=0.000). Further subgroup analysis showed significant differences in cerebrospinal fluid (CSF) S100ß (SMD: 0.87; 95% CI: 0.20 to 1.53) and low heterogeneity (I2: 59.8%; P=0.115). CONCLUSIONS: This meta-analysis provides evidence that serum S100ß seems to be of limited value as a biomarker of delirium, but CSF S100ß elevation may be more meaningful.

3.
Science ; 368(6487): 197-201, 2020 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-32273471

RESUMO

Vulnerability to relapse during periods of attempted abstinence from cocaine use is hypothesized to result from the rewiring of brain reward circuitries, particularly ventral tegmental area (VTA) dopamine neurons. How cocaine exposures act on midbrain dopamine neurons to precipitate addiction-relevant changes in gene expression is unclear. We found that histone H3 glutamine 5 dopaminylation (H3Q5dop) plays a critical role in cocaine-induced transcriptional plasticity in the midbrain. Rats undergoing withdrawal from cocaine showed an accumulation of H3Q5dop in the VTA. By reducing H3Q5dop in the VTA during withdrawal, we reversed cocaine-mediated gene expression changes, attenuated dopamine release in the nucleus accumbens, and reduced cocaine-seeking behavior. These findings establish a neurotransmission-independent role for nuclear dopamine in relapse-related transcriptional plasticity in the VTA.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/metabolismo , Transtornos Relacionados ao Uso de Cocaína/psicologia , Cocaína/efeitos adversos , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Comportamento de Procura de Droga , Histonas/metabolismo , Área Tegmentar Ventral/metabolismo , Animais , Transtornos Relacionados ao Uso de Cocaína/genética , Regulação da Expressão Gênica , Glutamina/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Plasticidade Neuronal , Núcleo Accumbens/metabolismo , Ratos , Ratos Sprague-Dawley , Transmissão Sináptica
4.
Front Biosci (Landmark Ed) ; 25: 1324-1336, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32114435

RESUMO

Glycerol-lactate esters are energy supplements for exercise, but effects of trilactic glyceride (TLG) on intestinal function and hepatic metabolism are unknown. We found that dietary supplementation with 0.5% TLG to weanling piglets decreased plasma concentrations of low-density lipoprotein and gamma-glutamyl transferase but increased those of D-xylose and high-density lipoprotein. TLG supplementation enhanced mRNA levels for fatty acid synthase (FASN) and SLC27A2 in white adipose tissue; insulin receptor in duodenum; aquaporin-8 in ileum, jejunum and colon; aquaporin-10 in duodenum and ileum; nuclear factor like-2 in jejunum and colon; glutathione S-transferase and phosphoenolpyruvate carboxykinase-1 in intestines; and abundances of claudin-1 and occludin proteins. TLG supplementation decreased mRNA levels for: hepatic hormone-sensitive lipase E, lipoprotein lipase, FASN, insulin-like growth factor-binding protein-3, and SLC27A2; and intestinal lipoprotein lipase, FASN and NADPH oxidase. Furthermore, TLG supplementation enhanced abundances of genus Bifidobacterium, while reducing abundances of family Enterobacteriaceae in ileum, colon and cecum; jejunal caspase-3 protein and diarrhea rate. In conclusion, dietary supplementation with TLG modulated lipid metabolism and alleviated diarrhea by improving intestinal function and regulating intestinal microflora in piglets.

5.
Biochem Biophys Res Commun ; 525(3): 759-766, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32145915

RESUMO

Formononetin (FN), a methoxy isoflavone abundant in many plants and herbs, has been evidently proven to possess multiple medicinal properties. Our study aimed to clarify the impact of FN on myocardial ischemia/reperfusion (I/R) injury (MIRI) and the involved mechanism. A rat model of MIRI was produced by ligation and loosening of the left anterior descending (LAD) branch of the coronary artery. Rats received 10 and 30 mg/kg of FN when the reperfusion started. At 24 h after surgery, cardiac function, infarct size, and sera levels of the cardiac markers and inflammatory mediators were measured. To mimic the inflammasome activation in cardiomyocytes, neonatal rat cardiomyocytes (NRCMs) were cultured and treated with lipopolysaccharide (LPS) plus nigericin. Cell death and reactive oxygen species (ROS) were determined. Myocardial expression and activation of the nucleotide-binding domain and leucine-rich repeat-containing protein 3 (NLRP3) inflammasome in rats were examined by western blotting. The level of thioredoxin interacting protein (TXNIP)-NLRP3 interaction was assessed. FN notably attenuated cardiac dysfunction, infarct size, release of cardiac markers, and elevation of TNF-α, IL-1ß, and IL-6. FN alleviated LPS plus nigericin-induced injury and ROS increase in NRCMs. Western blotting revealed that FN suppressed the activation of NLRP3 inflammasome and TXNIP-NLRP3 interaction in rats. These findings indicate that FN ameliorated MIRI in rats and inhibited the activation of the NLRP3 inflammasome, at least partially, attributable to suppression of the ROS-TXNIP-NLRP3 pathway.

6.
ACS Appl Mater Interfaces ; 12(15): 17936-17948, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32208630

RESUMO

To improve water solubility and bioavailability, curcumin (Cur) was encapsulated by liposomes (Cur-Lip), which was further coated with thiolated chitosan (CSSH) to form liposomal hydrogels (CSSH/Cur-Lip gel). The hydrogels were thermosensitive with in situ injectable performance, which were fluidic at room temperature and gelled quickly at 37 °C. The cumulative release ratio of the 200 µM CSSH/Cur-Lip gel was 31.57 ± 1.34% at 12 h, which could effectively delay the release of curcumin. Worthily, the resilient hydrogels were compressive even after five cycles of compression. The cytotoxicity test indicated that the liposomal hydrogels had good cytocompatibility, but after encapsulation of curcumin, MCF-7 cells were suppressed and killed dramatically after 72 h. The in vivo breast cancer recurrence experiment showed that the CSSH/Cur-Lip gel inhibited breast cancer recurrence after tumors were resected, and the tissue of defect in the CSSH/Cur-Lip gel group was repaired. The results showed that the drug-loaded liposomal hydrogels can deliver curcumin continuously and exerted an excellent tumoricidal effect in vitro and in vivo. The injectable, in situ-formable, and thermosensitive CSSH/Cur-Lip gel can be designed as a promising novel drug delivery vehicle to be used as carriers for local accurate and sustained drug delivery to minimize burst release and as tissue engineering scaffolds for tissue regeneration after tumor resection.

7.
Chin Med J (Engl) ; 133(1): 41-48, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31923103

RESUMO

BACKGROUND: The purpose of this study was to analyze cases of AO31-A2 intertrochanteric fractures (ITFs) and to identify the relationship between the loss of the posteromedial support and implant failure. METHODS: Three hundred ninety-four patients who underwent operative treatment for ITF from January 2003 to December 2017 were enrolled. Focusing on posteromedial support, the A2 ITFs were divided into two groups, namely, those with (Group A, n = 153) or without (Group B, n = 241) posteromedial support post-operatively, and the failure rates were compared. Based on the final outcomes (failed or not), we allocated all of the patients into two groups: failed (Group C, n = 66) and normal (Group D, n = 328). We separately analyzed each dataset to identify the factors that exhibited statistically significant differences between the groups. In addition, a logistic regression was conducted to identify whether the loss of posteromedial support of A2 ITFs was an independent risk factor for fixation failure. The basic factors were age, sex, American Society of Anesthesiologists (ASA) score, side of affected limb, fixation method (intramedullary or extramedullary), time from injury to operation, blood loss, operative time and length of stay. RESULTS: The failure rate of group B (58, 24.07%) was significantly higher than that of group A (8, 5.23%) (χ = 23.814, P < 0.001). Regarding Groups C and D, the comparisons of the fixation method (P = 0.005), operative time (P = 0.001), blood loss (P = 0.002) and length of stay (P = 0.033) showed that the differences were significant. The logistic regression revealed that the loss of posteromedial support was an independent risk factor for implant failure (OR = 5.986, 95% CI: 2.667-13.432) (P < 0.001). CONCLUSIONS: For AO31-A2 ITFs, the loss of posteromedial support was an independent risk factor for fixation failure. Therefore, posteromedial wall reconstruction might be necessary for the effective treatment of A2 fractures that lose posteromedial support.

8.
New Phytol ; 226(1): 244-253, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31536638

RESUMO

Nutrient distribution and neighbours can impact plant growth, but how neighbours shape root-foraging strategy for nutrients is unclear. Here, we explore new patterns of plant foraging for nutrients as affected by neighbours to improve nutrient acquisition. Maize (Zea mays) was grown alone (maize), or with maize (maize/maize) or faba bean (Vicia faba) (maize/faba bean) as a neighbour on one side and with or without a phosphorus (P)-rich zone on the other in a rhizo-box experiment. Maize demonstrated root avoidance in maize/maize, with reduced root growth in 'shared' soil, and increased growth away from its neighbours. Conversely, maize proliferated roots in the proximity of neighbouring faba bean roots that had greater P availability in the rhizosphere (as a result of citrate and acid phosphatase exudation) compared with maize roots. Maize proliferated more roots, but spent less time to reach, and grow out of, the P patches away from neighbours in the maize/maize than in the maize/faba bean experiment. Maize shoot biomass and P uptake were greater in the heterogeneous P treatment with maize/faba bean than with maize/maize system. The foraging strategy of maize roots is an integrated function of heterogeneous distribution of nutrients and neighbouring plants, thus improving nutrient acquisition and maize growth. Understanding the foraging patterns is critical for optimizing nutrient management in crops.

9.
Annu Rev Physiol ; 82: 227-249, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-31635526

RESUMO

Sensory neurons provide organisms with data about the world in which they live, for the purpose of successfully exploiting their environment. The consequences of sensory perception are not simply limited to decision-making behaviors; evidence suggests that sensory perception directly influences physiology and aging, a phenomenon that has been observed in animals across taxa. Therefore, understanding the neural mechanisms by which sensory input influences aging may uncover novel therapeutic targets for aging-related physiologies. In this review, we examine different perceptive experiences that have been most clearly linked to aging or age-related disease: food perception, social perception, time perception, and threat perception. For each, the sensory cues, receptors, and/or pathways that influence aging as well as the individual or groups of neurons involved, if known, are discussed. We conclude with general thoughts about the potential impact of this line of research on human health and aging.

10.
J Sci Food Agric ; 100(4): 1678-1686, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31803940

RESUMO

BACKGROUND: Nitrogen (N) fertilization influences plant growth and yield, and may also affect fruit quality. For two consecutive seasons, we examined the effects of various N fertilization levels - 5 to 200 mg L-1  - on pomegranate fruit, aril and juice quality. Evaluations included fruit and aril weight, size and color, appearance of peel blemishes, internal black rot and nutritional composition of extracted juices. RESULTS: Nitrogen fertilization affected pomegranate fruit, aril and juice quality. The most pronounced effects were observed in trees grown under the lowest N fertilization level, which bore smaller fruit and arils, the latter with lighter color; the fruit suffered from sunburn, and the juice had lower total soluble solid, acidity and anthocyanin contents. The proportion of edible aril weight per total fruit weight gradually increased with an increase in N fertilization concentration. In contrast, N fertilization did not affect peel color, roughness or cracking incidence. Black rot incidence increased with increasing N concentration. CONCLUSIONS: Nitrogen fertilization affected pomegranate fruit, aril and juice quality, and the total number of marketable fruits per tree. The optimal N fertilization levels, which were most beneficial for achieving high-quality marketable fruit, were between 40 and 100 mg L-1 . © 2019 Society of Chemical Industry.


Assuntos
Sucos de Frutas e Vegetais/análise , Nitrogênio/metabolismo , Romã (Fruta)/metabolismo , Fertilizantes/análise , Frutas/química , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Romã (Fruta)/química , Romã (Fruta)/crescimento & desenvolvimento , Controle de Qualidade
11.
IEEE Trans Cybern ; 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31634856

RESUMO

Flocking control has been studied extensively along with the wide applications of multivehicle systems. In this article, the distributed flocking control strategy is studied for a network of autonomous vehicles with limited communication range. The main difference from the existing methods lies in that collision avoidance is considered a necessary condition while the vehicles are driven to follow a common desired trajectory under the proximity network. The sufficient conditions for system feasibility and stability are given by the proposed strategy. First, a centralized standard model predictive control (MPC) scheme is adopted to formulate the multivehicle flocking control problem by setting collision avoidance as an optimization constraint under the proximity network. Further, an equivalent distributed MPC (DMPC) is developed based on the consensus of local controllers under the existing framework of the alternating direction method of multiplier (ADMM). However, it may require infinite time to achieve consensus for all vehicles and, thus, the local controllers resulting in a limited number of ADMM iterations may not satisfy the given constraints. The constraints for each local controller are then modified so that the collision between vehicles is avoided all of the time. The feasibility and stability of the proposed method are analyzed under practical conditions. Simulation and experimental results show that the flocking of vehicles can track the common desired trajectory stably with no collisions by the proposed method.

12.
Chin Med J (Engl) ; 132(21): 2534-2542, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31658157

RESUMO

BACKGROUND: Reverse intertrochanteric fractures are usually initially treated with closed reduction. However, sometimes these fractures are not amenable to closed reduction and require open reduction. To date, few studies have been conducted on predictors of and reduction techniques for irreducible reverse intertrochanteric fractures. Therefore, this study aimed to summarize the displacement patterns of irreducible reverse intertrochanteric fractures and corresponding reduction techniques, and explore predictors of irreducibility. METHODS: We reviewed 1174 cases of trochanteric fractures treated in our hospital from January 2006 to October 2018, 113 of which were reverse intertrochanteric fractures. An irreducible fracture was determined according to intra-operative fluoroscopy imaging after closed manipulation. Fractures were assessed for displacement patterns, radiographic features of irreducibility, and reduction techniques. Logistic regression analysis was performed on potential predictors for irreducibility, including gender, age, body mass index, AO Foundation/Orthopaedic Trauma Association (AO/OTA) classification, and radiographic features. RESULTS: Seventy-six irreducible fractures were identified, accounting for 67% of reverse intertrochanteric fractures. Six patterns of fracture displacement after closed manipulation were identified; the most common pattern was medial displacement and posterior sagging of the femoral shaft relative to the head-neck fragment. Multivariate logistic regression analysis identified three predictors of irreducibility: a medially displaced femoral shaft relative to the head-neck fragment on the anteroposterior (AP) view (odds ratio [OR], 8.00; 95% confidence interval [CI], 3.04-21.04; P < 0.001), a displaced lesser trochanter (OR, 3.61; 95% CI, 1.35-9.61; P = 0.010), and a displaced lateral femoral wall (OR, 2.92; 95% CI, 1.02-8.34; P = 0.046). CONCLUSIONS: A high proportion of reverse intertrochanteric fractures are not amenable to closed reduction. Six patterns of fracture displacement after closed manipulation were identified. Different reduction techniques are required for different displacement patterns. Predictors of irreducibility include a medially displaced femoral shaft relative to the head-neck fragment on the AP view, a displaced lesser trochanter, and a displaced lateral femoral wall. These patients warrant special consideration in terms of recognition and management.


Assuntos
Fraturas do Quadril/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Pinos Ortopédicos , Parafusos Ósseos , Feminino , Fraturas do Quadril/cirurgia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade
13.
Pharmacol Rep ; 71(5): 855-861, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31408784

RESUMO

BACKGROUND: Recent evidence indicates that Puerarin has a protective effect on pulmonary arteries. In the present study, we aimed to investigate whether Puerarin could protect pulmonary arterial endothelial cells from hypoxic injury and determine its potential targets. METHODS: In our study, human pulmonary arterial endothelial cells (HPAECs) were injured by hypoxic (1% O2) incubation. Cell viability was detected by a cell counting kit (CCK8). The production of nitric oxide (NO) was detected by Griess reagent and endothelin-1 (ET-1) was detected by the ELISA method. Oxidative stress was measured by a fluorescence microscope via the fluorescent probe DCFH-DA. Western blotting was employed for studying the mechanism. RESULTS: The results show that Puerarin protects HPAECs from hypoxia-induced apoptosis and slightly improves cell viability. Puerarin increases NO and decreases ET-1 to prevent the imbalance between vasoactive substances induced by hypoxia in HPAECs. Puerarin also inhibits the oxidative stress induced by hypoxia. The results from the Western blot show that Puerarin activates the BMPRII/Smad and PPARγ/PI3K/Akt signaling pathways. CONCLUSION: In conclusion, Puerarin protects HPAECs from hypoxic injury through the inhibition of oxidative stress and the activation of the BMPRII and PPARγ signaling pathways. This work provides insight into the development of Puerarin as a treatment for hypoxic pulmonary hypertension.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Células Endoteliais/efeitos dos fármacos , Isoflavonas/farmacologia , PPAR gama/metabolismo , Artéria Pulmonar/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Óxido Nítrico/biossíntese , Estresse Oxidativo/efeitos dos fármacos , Artéria Pulmonar/citologia , Artéria Pulmonar/metabolismo , Transdução de Sinais
14.
Nat Commun ; 10(1): 2875, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253766

RESUMO

The charge and spin of the electrons in solids have been extensively exploited in electronic devices and in the development of spintronics. Another attribute of electrons-their orbital nature-is attracting growing interest for understanding exotic phenomena and in creating the next-generation of quantum devices such as orbital qubits. Here, we report on orbital-flop induced magnetoresistance anisotropy in CeSb. In the low temperature high magnetic-field driven ferromagnetic state, a series of additional minima appear in the angle-dependent magnetoresistance. These minima arise from the anisotropic magnetization originating from orbital-flops and from the enhanced electron scattering from magnetic multidomains formed around the first-order orbital-flop transition. The measured magnetization anisotropy can be accounted for with a phenomenological model involving orbital-flops and a spin-valve-like structure is used to demonstrate the viable utilization of orbital-flop phenomenon. Our results showcase a contribution of orbital behavior in the emergence of intriguing phenomena.

15.
Nat Commun ; 10(1): 2365, 2019 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-31147540

RESUMO

Sensory perception modulates health and aging across taxa. Understanding the nature of relevant cues and the mechanisms underlying their action may lead to novel interventions that improve the length and quality of life. We found that in the vinegar fly, Drosophila melanogaster, exposure to dead conspecifics in the environment induced cues that were aversive to other flies, modulated physiology, and impaired longevity. The effects of exposure to dead conspecifics on aversiveness and lifespan required visual and olfactory function in the exposed flies. Furthermore, the sight of dead flies was sufficient to produce aversive cues and to induce changes in the head metabolome. Genetic and pharmacologic attenuation of serotonergic signaling eliminated the effects of exposure on aversiveness and lifespan. Our results indicate that Drosophila have an ability to perceive dead conspecifics in their environment and suggest conserved mechanistic links between neural state, health, and aging; the roots of which might be unearthed using invertebrate model systems.


Assuntos
Sinais (Psicologia) , Morte , Longevidade , Percepção Olfatória , Serotonina/metabolismo , Percepção Visual , Animais , Dióxido de Carbono/metabolismo , Drosophila , Proteínas de Drosophila/genética , Drosophila melanogaster , Drosophila simulans , Metaboloma , Fosfolipase C beta/genética , Receptores Odorantes/genética , Transdução de Sinais , Triglicerídeos/metabolismo
16.
Materials (Basel) ; 12(6)2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30917534

RESUMO

Tetraethyl orthosilicate was selected as a matrix of heat insulating materials among three silanes, and an anti-infrared radiation fiber was chosen as a reinforcement for silica aerogel insulation composite. The silica aerogel was combined well and evenly distributed in the anti-infrared radiation fiber. The heat insulation effect was improved with the increase in thickness of the aerogel insulation material, as determined by the self-made aerospace insulation material insulation performance test equipment. The 15 mm and 30 mm thick thermal insulation material heated at 250 °C for 3 h, the temperatures at the cold surface were about 80 °C and 60 °C, respectively, and the temperatures at 150 mm above the cold surface were less than 60 °C and 50 °C, respectively. The silica aerogel composites with various thicknesses showed good thermal insulation stability. The silica insulation composite with a thickness of 15 mm exhibited good heat insulation performance, meets the thermal insulation requirements of general equipment compartments under low-temperature and long-term environmental conditions. The thermal conductivity of prepared silica aerogel composite was 0.0191 W·m-1·k-1 at room temperature and 0.0489 W·m-1·k-1 at 500 °C.

17.
Nature ; 567(7749): 535-539, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30867594

RESUMO

Chemical modifications of histones can mediate diverse DNA-templated processes, including gene transcription1-3. Here we provide evidence for a class of histone post-translational modification, serotonylation of glutamine, which occurs at position 5 (Q5ser) on histone H3 in organisms that produce serotonin (also known as 5-hydroxytryptamine (5-HT)). We demonstrate that tissue transglutaminase 2 can serotonylate histone H3 tri-methylated lysine 4 (H3K4me3)-marked nucleosomes, resulting in the presence of combinatorial H3K4me3Q5ser in vivo. H3K4me3Q5ser displays a ubiquitous pattern of tissue expression in mammals, with enrichment observed in brain and gut, two organ systems responsible for the bulk of 5-HT production. Genome-wide analyses of human serotonergic neurons, developing mouse brain and cultured serotonergic cells indicate that H3K4me3Q5ser nucleosomes are enriched in euchromatin, are sensitive to cellular differentiation and correlate with permissive gene expression, phenomena that are linked to the potentiation of TFIID4-6 interactions with H3K4me3. Cells that ectopically express a H3 mutant that cannot be serotonylated display significantly altered expression of H3K4me3Q5ser-target loci, which leads to deficits in differentiation. Taken together, these data identify a direct role for 5-HT, independent from its contributions to neurotransmission and cellular signalling, in the mediation of permissive gene expression.


Assuntos
Regulação da Expressão Gênica , Histonas/química , Histonas/metabolismo , Lisina/metabolismo , Processamento de Proteína Pós-Traducional , Serotonina/metabolismo , Fator de Transcrição TFIID/metabolismo , Animais , Diferenciação Celular , Linhagem Celular , Feminino , Proteínas de Ligação ao GTP/metabolismo , Glutamina/química , Glutamina/metabolismo , Humanos , Metilação , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica , Neurônios Serotoninérgicos/citologia , Transglutaminases/metabolismo
18.
Nat Commun ; 10(1): 287, 2019 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-30655544

RESUMO

Negative longitudinal magnetoresistances (NLMRs) have been recently observed in a variety of topological materials and often considered to be associated with Weyl fermions that have a defined chirality. Here we report NLMRs in non-Weyl GaAs quantum wells. In the absence of a magnetic field the quantum wells show a transition from semiconducting-like to metallic behaviour with decreasing temperature. We observe pronounced NLMRs up to 9 Tesla at temperatures above the transition and weak NLMRs in low magnetic fields at temperatures close to the transition and below 5 K. The observed NLMRs show various types of magnetic field behaviour resembling those reported in topological materials. We attribute them to microscopic disorder and use a phenomenological three-resistor model to account for their various features. Our results showcase a contribution of microscopic disorder in the occurrence of unusual phenomena. They may stimulate further work on tuning electronic properties via disorder/defect nano-engineering.

19.
Int J Ophthalmol ; 11(5): 726-735, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29862169

RESUMO

AIM: To investigate the roles of integrins in choroidal neovascularization (CNV) and their associations with the stromal cell-derived factor-1 (SDF-1)/CXCR4 axis. METHODS: CNV lesions were induced in mice using laser photocoagulation. After CNV induction, all animals were randomly assigned to: control, SDF-1, SDF-1+age-related macular degeneration (AMD) 3100 (CXCR4 inhibitor), and SDF-1+ATN161 (integrin α5ß1 inhibitor) groups; their effects on CNV progression were observed using hematoxylin eosin (HE) staining, fundus fluorescein angiography (FFA) grading and optical coherence tomography (OCT), and their effects on CXCR4/integrin α5 expression were evaluated using Western blot and double immunofluorescence staining. Hypoxia-exposed endothelial cells (ECs) were used to simulate CNV in vitro, they were treated with SDF-1, combined with CXCR4 siRNA/AMD3100 or ATN161, and expression of integrin α5, cell migration and tube formation were analyzed. RESULTS: Integrin subunit α5 increased at 3rd and 7th day and decreased at 14th day in CNV mice, with no significant change of ß1-integrin. CXCR4 expression in CNV mice had persistent increase within 14d after induction. SDF-1 treatment significantly promoted the CNV progression during 3-14d. The mean CNV length in AMD3100 and ATN161 group at day 7 was 270.13 and 264.23 µm in HE images, significantly lower than the mean length in SDF-1 (345.70 µm) group. AMD3100 and ATN161 also significantly reduced thickness and leakage of CNV induced by SDF-1. Mean integrin α5 positive area in SDF-1 group reached 2.31×104 µm2, significantly higher than control (1.25×104 µm2), which decreased to 1.78×104 µm2 after AMD3100 treatment. About 61.36% of ECs in CNV lesions expressed α5 in SDF-1 group, which significantly decreased to 43.12% after AMD3100 treatment. In vitro, integrin α5 peaked by 6 folds after 6h of hypoxia exposure and CXCR4 gradually increased by up to 2.3 folds after 24h of hypoxia. Approximately 25.12% of ECs expressed integrin α5 after SDF-1 stimulation, which decreased to 7.2%-9.5% after si-CXCR4 or AMD3100 treatment. ATN161 exerted an inhibitory effect comparable to that of si-CXCR4 on EC migration and tube formation in the presence of SDF-1. CONCLUSION: SDF-1/CXCR4 signaling induces integrin α5ß1 expression in ECs to promote CNV.

20.
Zhonghua Wei Chang Wai Ke Za Zhi ; 21(5): 564-568, 2018 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-29774940

RESUMO

OBJECTIVE: To investigate clinicopathological features and prognostic factors of appendiceal neuroendocrine neoplasms(a-NEN). METHODS: Clinical data of 20 patients diagnosed with a-NEN at Zhongshan Hospital of Fudan University between January 2000 and December 2016 were retrospectively analyzed. Pathological diagnosis was based on the WHO classification criteria of digestive system tumors (2010 edition). Based on the mitotic count and Ki-67 index, a-NENs were divided into grade 1 neuroendocrine tumor (NET G1), grade 2(G2) NET G2) and grade 3 (neuroendocrine carcinoma, NEC). Some special types of a-NEN (e.g. goblet cell carcinoid) and mixed adenoneuroendocrine neoplasms were classified as mixed adenoneuroendocrine carcinoma (MANEC). Follow-up was conducted by telephone or return visits. Univariate analysis was carried out using the Kaplan-Meier method, and the log-rank test was used to draw survival curves. RESULTS: Of 20 patients, 14 were male and 6 were female with median age of 54 years. Seventeen cases presented acute right lower quadrant abdominal pain, 1 chronic right lower quadrant abdominal pain, 1 persistent abdominal discomfort with outburst whole abdominal pain and 1 was found during body check without symptoms. Twenty cases comprised 8 G1 patients, 4 G2 patients, 3 G3 patients, and 5 MANEC patients. When diagnosed, there was 1 patient with liver metastasis, 1 patient with abdominal and pelvic metastases, and 2 patients with postoperative pathological findings of lymph node metastasis. Six patients underwent appendectomy, 12 underwent right hemicolectomy, 1 underwent right hemicolectomy plus small intestine resection, and 1 underwent partial hepatectomy plus right hemicolectomy. The follow-up time was 7-187 months(average, 36 months). The total 1- and 3-year survival rates were 94.7% and 60.2%, respectively. Univariate analysis showed that age >50 years (χ2=7.036, P=0.008), pathology grade as MANEC (χ2=5.297, P=0.021), and metastasis (χ2=6.558, P=0.010) indicated lower 5-year survival rate. CONCLUSIONS: Most a-NEN patients have no typical symptoms, and the main complaint at consultation is acute right lower quadrant abdominal pain. Prognosis is poor for patients with age >50 years, MANEC pathology grade and metastasis.


Assuntos
Neoplasias do Apêndice , Tumores Neuroendócrinos , Neoplasias do Apêndice/complicações , Neoplasias do Apêndice/diagnóstico , Neoplasias do Apêndice/cirurgia , Carcinoma Neuroendócrino/complicações , Carcinoma Neuroendócrino/diagnóstico , Carcinoma Neuroendócrino/terapia , Feminino , Neoplasias Gastrointestinais , Humanos , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/complicações , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/cirurgia , Prognóstico , Estudos Retrospectivos
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