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1.
Nano Lett ; 24(22): 6665-6672, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38767991

RESUMEN

Shape morphing of biopolymer materials, such as chitosan (CS) films, has great potential for applications in many fields. Traditionally, their responsive behavior has been induced by the differential water swelling through the preparation of multicomponent composites or cross-linking as deformation is not controllable in the absence of these processes. Here, we report an interfacial dehydration strategy to trigger the shape morphing of the monocomponent CS film without cross-linking. The release of water molecules is achieved by spraying the surface with a NaOH solution or organic solvents, which results in the interfacial shrinkage and deformation of the entire film. On the basis of this strategy, a range of CS actuators were developed, such as soft grippers, joint actuators, and a light switch. Combined with the geometry effect, edited deformation was also achieved from the planar CS film. This shape-morphing strategy is expected to enable the application of more biopolymers in a wide range of fields.

2.
Opt Express ; 32(6): 9699-9709, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38571198

RESUMEN

In order to enhance the performance of a continuous-wave photocathode electron gun at Peking University, and to achieve electron beams with higher current and brightness, a multifunctional drive laser system named PULSE (Peking University drive Laser System for high-brightness Electron source) has been developed. This innovative system is capable of delivering an average output power of 120 W infrared laser pulse at 81.25 MHz, as well as approximately 13.8 W of green power with reliable stability. The utilization of two stages of photonic crystal fibers plays a crucial role in achieving this output. Additionally, the incorporation of two acousto-optic modulators enables the selection of macro-pulses with varying repetition frequencies and duty cycles, which is essential for effective electron beam diagnosis. Furthermore, the system employs a series of birefringent crystals for temporal pulse shaping, allowing for stacking Gaussian pulses into multiple types of distribution. Overall, the optical schematic and operating performance of PULSE are detailed in this paper.

3.
J Environ Sci (China) ; 138: 102-111, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38135379

RESUMEN

Aiming at purification of NOx from hydrogen internal combustion engines (HICEs), the hydrogen selective catalytic reduction (H2-SCR) reaction was investigated over a series of Pt/KFI zeolite catalysts. H2 can readily reduce NOx to N2 and N2O while O2 inhibited the deNOx efficiency by consuming the reductant H2. The Pt/KFI zeolite catalysts with Pt loading below 0.1 wt.% are optimized H2-SCR catalysts due to its suitable operation temperature window since high Pt loading favors the H2-O2 reaction which lead to the insufficient of reactants. Compared to metal Pt0 species, Ptδ+ species showed lower activation energy of H2-SCR reaction and thought to be as reasonable active sites. Further, Eley-Rideal (E-R) reaction mechanism was proposed as evidenced by the reaction orders in kinetic studies. Last, the optimized reactor was designed with hybrid Pt/KFI catalysts with various Pt loading which achieve a high NOx conversion in a wide temperature range.


Asunto(s)
Hidrógeno , Zeolitas , Hidrógeno/química , Oxidación-Reducción , Cinética , Amoníaco/química , Catálisis
4.
Environ Sci Technol ; 57(10): 4308-4317, 2023 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-36808994

RESUMEN

The complex poisoning of Cu-KFI catalysts by SO2 and hydrothermal aging (HTA) was investigated. The low-temperature activity of Cu-KFI catalysts was restrained by the formation of H2SO4 and then CuSO4 after sulfur poisoning. Hydrothermally aged Cu-KFI exhibited better SO2 resistance than fresh Cu-KFI since HTA significantly reduced the number of Brønsted acid sites, which were considered to be the H2SO4 storage sites. The high-temperature activity of SO2-poisoned Cu-KFI was basically unchanged compared to the fresh catalyst. However, SO2 poisoning promoted the high-temperature activity of hydrothermally aged Cu-KFI since it triggered CuOx into CuSO4 species, which was considered as an important role in the NH3-SCR reaction at high temperatures. In addition, hydrothermally aged Cu-KFI catalysts were more easily regenerated after SO2 poisoning than fresh Cu-KFI on account of the instability of CuSO4.


Asunto(s)
Amoníaco , Oxidación-Reducción , Temperatura , Catálisis
5.
Int J Mol Sci ; 24(14)2023 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-37511287

RESUMEN

In this study, a transcriptomic analysis of the dehydration rate of mature rice seeds was conducted to explore candidate genes related to the dehydration rate and provide a theoretical basis for breeding and utilization. We selected two rice cultivars for testing (Baghlani Nangarhar, an extremely rapid dehydration genotype, and Saturn, a slow dehydration genotype) based on the results determined by previous studies conducted on the screening of 165 germplasm materials for dehydration rate phenotypes. A rapid dehydration experiment performed on these two types of seeds was conducted. Four comparative groups were set up under control and dehydration conditions. The differentially expressed genes (DEGs) were quantified via transcriptome sequencing and real-time quantitative PCR (RT-qPCR). GO (Gene ontology) and KEGG(Kyoto Encyclopedia of Genes and Genomes) analyses were also conducted. In Baghlani Nangarhar, 53 DEGs were screened, of which 33 were up-regulated and 20 were down-regulated. In Saturn, 25 DEGs were screened, of which 19 were up-regulated and 6 were down-regulated. The results of the GO analysis show that the sites of action of the differentially expressed genes enriched in the rapid dehydration modes are concentrated in the cytoplasm, internal components of the membrane, and nucleosomes. They play regulatory roles in the processes of catalysis, binding, translocation, transcription, protein folding, degradation, and replication. They are also involved in adaptive responses to adverse external environments, such as reactive oxygen species and high temperature. The KEGG analysis showed that protein processing in the endoplasmic reticulum, amino acid biosynthesis, and oxidative phosphorylation were the main metabolic pathways that were enriched. The key differentially expressed genes and the most important metabolic pathways identified in the rapidly and slowly dehydrated genotypes were protein processing in the endoplasmic reticulum and oxidative phosphorylation metabolism. They were presumed to have important regulatory roles in the mechanisms of stress/defense, energy metabolism, protein synthesis/folding, and signal transduction during the dehydration and drying of mature seeds. The results of this study can potentially provide valuable information for further research on the genes and metabolic pathways related to the dehydration rate of mature rice seeds, and provide theoretical guidance for the selection and breeding of new rice germplasm that can be rapidly dehydrated at the mature stage.


Asunto(s)
Oryza , Transcriptoma , Oryza/genética , Oryza/metabolismo , Deshidratación/genética , Fitomejoramiento , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Semillas/genética
6.
Molecules ; 28(8)2023 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-37110735

RESUMEN

In the current article, the effect of Si/Al ratio on the NOx adsorption and storage capacity over Pd/Beta with 1 wt% Pd loading was investigated. The XRD, 27Al NMR and 29Si NMR measurements were used to determine the structure of Pd/Beta zeolites. XAFS, XPS, CO-DRIFT, TEM and H2-TPR were used to identify the Pd species. The results showed that the NOx adsorption and storage capacity on Pd/Beta zeolites gradually decreased with the increase of Si/Al ratio. Pd/Beta-Si (Si-rich, Si/Al~260) rarely has NOx adsorption and storage capacity, while Pd/Beta-Al (Al-rich, Si/Al~6) and Pd/Beta-C (Common, Si/Al~25) exhibit excellent NOx adsorption and storage capacity and suitable desorption temperature. Pd/Beta-C has slightly lower desorption temperature compared to Pd/Beta-Al. The NOx adsorption and storage capacity increased for Pd/Beta-Al and Pd/Beta-C by hydrothermal aging treatment, while the NOx adsorption and storage capacity on Pd/Beta-Si had no change.

7.
Environ Sci Technol ; 56(24): 17946-17954, 2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36322164

RESUMEN

A comparative study was performed to investigate the NH3-selective catalytic reduction (SCR) reaction activity of Cu-SSZ-13 zeolites having Si/Al ratios (SARs) of 5, 18, and 30. Remarkably, the Cu-SSZ-13 zeolite catalysts exhibited completely opposite behaviors as a function of SAR under standard SCR (SSCR) and fast SCR (FSCR) reaction atmospheres. Under SSCR conditions, the NOx conversion increased as expected with the decreasing SAR. Under FSCR conditions, however, the NOx conversion decreased as the SAR decreased, contrary to expectations. In this study, based on characterization of the catalysts by X-ray diffraction, transmission electron microscopy, electron paramagnetic resonance, H2-temperature-programmed reduction, temperature-programmed desorption, and diffuse reflectance infrared Fourier transform spectroscopy, together with theoretical calculations, the authors found that the amount of Brønsted acid sites goes up while the SAR goes down, leading to an increase in the accumulation of NH4NO3 under FSCR reaction conditions. Moreover, the accumulated NH4NO3 is of greater stability for those low SAR Cu-SSZ-13 catalysts. These two reasons cause the FSCR performance of Cu-SSZ-13 to decrease with a decrease in SAR. As a result, the NO2 effect on SCR activity changes from promotion to inhibition as the SAR decreases.

8.
J Craniofac Surg ; 33(8): 2507-2512, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36409870

RESUMEN

OBJECTIVES: To find out the occurrence rate and risk factors of unplanned reoperation (any unscheduled surgery within 30 d after the initial surgery) in patients who have received oral squamous cell carcinoma (OSCC) surgery and vascularized free flap reconstruction. PATIENTS AND METHODS: We organized a retrospective study of 1058 patients who underwent OSCC resection and reconstruction with vascularized free flaps from 2011 to 2019. Clinical characteristics, reasons for unplanned reoperation, flap types, and previous treatment were compared between the unplanned reoperation group and the control group. Univariate and multivariate analyses were performed to identify perioperative risk factors for unplanned reoperation. The related perioperative factors that may influence perioperative infusion were included in propensity score matching to investigate the independent contribution of intraoperative colloid infusion on unplanned reoperation. RESULTS: The overall rate of unplanned reoperation in OSCC patients was 11% (n=115). Flap necrosis and bleeding were the most common causes. Higher American Society of Anesthesiologists (ASA) grade [odds ratio (OR)=1.709, P=0.009], postoperative anemia (OR=0.983, P=0.011) and excessive intraoperative colloid input (OR=1.55, P=0.037) were identified as risk factors for unplanned reoperation. Propensity score matching was applied, and the difference of unplanned reoperation incidence between the matched groups was statistically significant (14.59% versus 8.54%; P=0.025). The multivariate analyses after propensity score matching confirmed that the intraoperative rate of colloid infusion of more than 2.3 mL/kg/h (OR=1.756, P=0.042) and prior radiotherapy (OR=2.78, P=0.001) are independent risk factors for unplanned reoperation. CONCLUSION: High intraoperative colloid infusion rate and prior radiotherapy may increase the risk of unplanned reoperation in patients who underwent OSCC surgery and vascularized free flap reconstruction.


Asunto(s)
Carcinoma de Células Escamosas , Colgajos Tisulares Libres , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Humanos , Reoperación , Carcinoma de Células Escamosas de Cabeza y Cuello , Neoplasias de la Boca/cirugía , Carcinoma de Células Escamosas/cirugía , Estudios Retrospectivos , Factores de Riesgo
9.
BMC Infect Dis ; 21(1): 593, 2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34157968

RESUMEN

BACKGROUND: Unprotected anal intercourse (UAI) within the context of concurrent sexual relationship are prevalent among men who have sex with men (MSM) who have regular male sex partners and it aggravates the risk of HIV infection among this community. The aim of this study was to assess the effect of intimate relationship characteristics on UAI among MSM couples at the dyadic level. METHODS: Two hundred four MSM couples were recruited from a HIV testing clinic from April 2017 to April 2018 in Guangzhou, China. The actor-partner interdependence model (APIM) was applied for dyadic analysis. Each MSM couple was divided into the insertive role and the receptive role according to their regular anal sex role. In this context, actor effect is the impact of an MSM's intimate relationship characteristics on his own UAI, and partner effect is the impact of his partner's intimate relationship characteristics on his UAI. RESULTS: Of the 408 participants, 58.82% had UAI with regular male sex partner (UAI-RP) and 8.09% had concurrent UAI. Intimate relationship characteristics were associated with concurrent UAI, but not associated with UAI-RP. For the receptive role, his relationship investment exerted significant actor and partner effects on concurrent UAI (AOR actor = 1.31, P < 0.001; AOR partner = 1.17, P < 0.001). Meanwhile, receptive role's violence experience within relationship exerted significant actor effects on his own concurrent UAI (AOR actor = 6.43, P = 0.044). CONCLUSIONS: Relationship investment and violence experience influenced concurrent UAI among MSM couples and it varied in different sex roles. Additional assistance on empowerment, relationship therapy and sexual agreement is urgently needed to reduce their high possibility on engagement of HIV-related risk behaviors.


Asunto(s)
Homosexualidad Masculina/psicología , Relaciones Interpersonales , Conducta Sexual , Parejas Sexuales/psicología , Minorías Sexuales y de Género/psicología , Sexo Inseguro , Adulto , China , Humanos , Masculino
10.
Ecotoxicol Environ Saf ; 211: 111921, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33486382

RESUMEN

Citric acid (CA) can regulate the balance of anions and cations in plants, and improve their resistance to heavy metals. It is not clear if foliar application with CA has any effect on migration of Cd and Mn in rice plant. In this work, a low-Cd-accumulating indica rice line (P7) and a high-Cd-accumulating line (HZ) were used to investigate the influence of CA on the transport of Cd and Mn as well as amino acid metabolism in grains. Content of Cd in grains and other organs increased with the increase of Cd content (0.1-2.4 mg kg-1) in soil, while decreased with the foliar application with CA. With the increase of Cd content in rice grains, the content of most amino acids in HZ, P7, HZ+CA and P7 + CA showed an obvious decline trend. Foliar application with CA efficiently raised the Mn:Cd ratio in grains and nodes of both HZ and P7. Meanwhile, the expression levels of OsNramp2, 3 and 5 in panicles were efficiently enhanced by CA application when plants grew in soil with Cd content of 0.6-2.4 mg kg-1. The increasing effect of CA on the content of 4 amino acids (i.e., Glu, Phe, Thr and Ala) in grains was related to varieties and Cd pollution. These results indicate that foliar application with CA can regulate the transport of Cd and Mn in the opposite directions in tissues and inhibit Cd accumulation in grains by enhancing expression of OsNRAMP 2, 3 or 5 and triggering the defense response of some amino acids in Cd-contaminated environment.


Asunto(s)
Aminoácidos/metabolismo , Cadmio/metabolismo , Ácido Cítrico/farmacología , Grano Comestible/fisiología , Manganeso/metabolismo , Sustancias Protectoras/farmacología , Transporte Biológico , Contaminación Ambiental , Metales Pesados/análisis , Oryza/metabolismo , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Suelo/química , Contaminantes del Suelo/análisis
11.
Nat Mater ; 18(6): 608-613, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30911121

RESUMEN

Converting low-grade heat into useful electricity requires a technology that is efficient and cost effective. Here, we demonstrate a cellulosic membrane that relies on sub-nanoscale confinement of ions in oxidized and aligned cellulose molecular chains to enhance selective diffusion under a thermal gradient. After infiltrating electrolyte into the cellulosic membrane and applying an axial temperature gradient, the ionic conductor exhibits a thermal gradient ratio (analogous to the Seebeck coefficient in thermoelectrics) of 24 mV K-1-more than twice the highest value reported until now. We attribute the enhanced thermally generated voltage to effective sodium ion insertion into the charged molecular chains of the cellulosic membrane, which consists of type II cellulose, while this process does not occur in natural wood or type I cellulose. With this material, we demonstrate a flexible and biocompatible heat-to-electricity conversion device via nanoscale engineering based on sustainable materials that can enable large-scale manufacture.

12.
J Oral Maxillofac Surg ; 78(12): 2316-2327, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32866482

RESUMEN

PURPOSE: Blood transfusion is usually a common clinical practice in flap transfer surgery because of its invasive hemorrhagic nature. Although intraoperative restrictive transfusion policy was suggested in vascularized fibular flap reconstruction, its clinical evidence was still insufficient. Therefore, our study aimed to investigate the influence of intraoperative blood transfusion on length of stay (LOS) after vascularized fibular flap reconstruction. PATIENTS AND METHODS: Patients who underwent vascularized fibular flap reconstruction of mandibulofacial defects between 2012 and 2018 were reviewed. Univariate and multivariate analyses were performed to identify factors that influenced LOS. The identified factors and other perioperative factors that may influence transfusion decision were included in propensity score matching to explore the independent impact of intraoperative blood transfusion on LOS. RESULTS: About 375 patients were included, and the median LOS was 14.00 (12.00, 19.00) days in our study. Multivariate analysis suggested that duration of surgery, fluid infusion speed for more than 24 hours on operative day, intraoperative blood transfusion, and postoperative complication were associated with prolonged LOS (P < .05). Propensity score matching was performed, and the difference of LOS between the matched transfused and nontransfused group was statistically significant (15.00 [12.75, 20.00] vs 14.00 [11.75, 16.25]; P < .001). The comparison between the matched and unmatched transfused patients indicated that the former has less radiotherapy history, blood loss, and higher preoperative hemoglobin (P ≤ .001). CONCLUSIONS: Intraoperative blood transfusion is independently associated with prolonged LOS in patients without preoperative anemia, radiotherapy history, or intraoperative massive hemorrhage who undergo vascularized fibular flap reconstruction. Efforts should be made to avoid unnecessary intraoperative blood transfusion, and our results support consideration of a restrictive transfusion policy in these patients.


Asunto(s)
Transfusión Sanguínea , Complicaciones Posoperatorias , Humanos , Tiempo de Internación , Puntaje de Propensión , Estudios Retrospectivos
13.
J Med Internet Res ; 22(1): e13201, 2020 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-32012054

RESUMEN

BACKGROUND: Affective states, including sentiment and emotion, are critical determinants of health. However, few studies among men who have sex with men (MSM) have examined sentiment and emotion specifically using real-time social media technologies. Moreover, the explorations on their associations with sexual and health status among MSM are limited. OBJECTIVE: This study aimed to understand and examine the associations of affective states with sexual behaviors and health status among MSM using public data from the Blued (Blued International Inc) app. METHODS: A total of 843,745 public postings of 377,610 MSM users located in Guangdong were saved from the Blued app by automatic screen capture. Positive affect, negative affect, sexual behaviors, and health status were measured using the Simplified Chinese Linguistic Inquiry and Word Count. Emotions, including joy, sadness, anger, fear, and disgust, were measured using the Weibo Basic Mood Lexicon. A positive sentiment score and a positive emotion score were also calculated. Univariate and multivariate linear regression models on the basis of a permutation test were used to assess the associations of affective states with sexual behaviors and health status. RESULTS: A total of 5871 active MSM users and their 477,374 postings were finally selected. Both positive affect and positive emotions (eg, joy) peaked between 7 AM and 9 AM. Negative affect and negative emotions (eg, sadness and disgust) peaked between 2 AM and 4 AM. During that time, 25.1% (97/387) of negative postings were related to health and 13.4% (52/387) of negative postings were related to seeking social support. A multivariate analysis showed that the MSM who were more likely to post sexual behaviors were more likely to express positive affect (beta=0.3107; P<.001) and positive emotions (joy: beta=0.027; P<.001), as well as negative emotions (sadness: beta=0.0443; P<.001 and disgust: beta=0.0256; P<.001). They also had a higher positive sentiment score (beta=0.2947; P<.001) and a higher positive emotion score (beta=0.1612; P<.001). The MSM who were more likely to post their health status were more likely to express negative affect (beta=0.8088; P<.001) and negative emotions, including sadness (beta=0.0705; P<.001), anger (beta=0.0058; P<.001), fear (beta=0.0052; P<.001), and disgust (beta=0.3065; P<.001), and less likely to express positive affect (beta=-0.0224; P=.02). In addition, they had a lower positive sentiment score (beta=-0.8306; P<.001) and a lower positive emotion score (beta=-0.3743; P<.001). CONCLUSIONS: The MSM social media community mainly expressed their positive affect in the early morning and negative affect after midnight. Positive affective states were associated with being sexually active, whereas negative affective states were associated with health problems, mostly about mental health. Our finding suggests the potential to deliver different health-related intervention strategies (eg, psychological counseling and safe sex promotion) on a social media app according to the affective states of MSM in real time.


Asunto(s)
Homosexualidad Masculina/psicología , Conducta Sexual/psicología , Medios de Comunicación Sociales/normas , Adulto , China , Humanos , Masculino
15.
J Craniofac Surg ; 31(2): 381-384, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31821214

RESUMEN

PURPOSE: To determine perioperative risk factors predicted complications in elderly Chinese patients undergoing oral and maxillofacial reconstruction with radial forearm free flaps (RFFF). PATIENTS AND METHODS: The authors implemented a retrospective study and enrolled a sample of patients at least 65-year old who underwent resection of oral and maxillofacial tumors and RFFF reconstruction from January 2011 to June 2018. Predictor variables were divided into: demographic variables (gender, age, weight, comorbidities, history of smoking, radiotherapy history, primary lesions); hemodynamic (preoperative and postoperative hemoglobin and albumin level, blood loss, blood transfusion, urine output (mL), and rate (mL/kg/h), and infusion rates for crystalloids and colloids (mL/kg/h, and volumes given intraoperatively and postoperatively for 24 hours); anesthetic and surgical (American Society of Anesthesiologists classification, visual analogue score, duration of tourniquet, and operation). The primary outcome was the presence of postoperative complications (yes/no), and secondary outcome was types of complications (medical and surgical). All the variables were analyzed by univariate and multivariable analysis and statistical significance was set at a P < 0.05 RESULTS:: The study sample was composed of 118 patients with a mean age of 72 years. There were 15 complications, of which 9 were surgical and 6 medical. Risk factors were: postoperative hypoproteinemia, crystal in 24 hours, and hypertension combined with diabetes. CONCLUSIONS: Although reconstruction with a RFFF is a common and safe treatment for elderly patients with oral and maxillofacial tumors, postoperative hypoproteinemia, crystal in 24 hours, and hypertension combined with diabetes are potential predictors of postoperative complications.


Asunto(s)
Colgajos Tisulares Libres/cirugía , Procedimientos de Cirugía Plástica/efectos adversos , Complicaciones Posoperatorias , Anciano , Anciano de 80 o más Años , Femenino , Antebrazo/cirugía , Humanos , Masculino , Periodo Posoperatorio , Estudios Retrospectivos , Factores de Riesgo
16.
Pharmacology ; 104(5-6): 276-286, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31494660

RESUMEN

BACKGROUND: Surgery plays a significant role in the comprehensive treatment of breast cancer, and opioids are often the first-choice analgesics in the perioperative period. However, recent studies showed that opioids may enhance the angiogenesis of breast cancer and the recurrence and metastasis of tumor cells. OBJECTIVES: We aim to investigate the influence of opioids on recurrence and metastasis of breast cancer in nude mice. METHODS: Forty female nude mice with breast tumor were randomly divided into 4 groups (n = 10). They were treated with (i) normal saline (10 mL/kg), (ii) morphine (10 mg/kg), (iii) morphine plus naloxone (10 + 4 mg/kg), and (iv) naloxone (4 mg/kg) for 2 weeks. Four groups of MDA-MB-231 cells were administered (i) Dulbecco's Modified Eagle's Medium, (ii) morphine (10 µmol/mL), (iii) morphine plus naloxone (10 + 10 µmol/mL), and (iv) naloxone (10 µmol/mL). The influence of morphine in each treated group was evaluated by immunocytochemistry and Western blotting. RESULTS: Mice in the morphine group had higher rates of Ki67-positive cells, lower rates of apoptotic index, and a significant increase in the microvessels density of the tumor as evidenced by CD31 staining (p < 0.05). Furthermore, the MDA-MB-231 cells in the morphine group showed an increase in p-Akt, c-Myc, and thrombosponin-1 expression. CONCLUSION: In the current study, we found that morphine promotes the angiogenesis of the recurrent postoperative tumors of nude mice with breast cancer and the proliferation of tumor cells and such promotion may be related to the PI3K-c-Myc signaling pathway.


Asunto(s)
Adenocarcinoma/patología , Analgésicos Opioides/efectos adversos , Neoplasias Mamarias Experimentales/patología , Morfina/efectos adversos , Recurrencia Local de Neoplasia/patología , Neovascularización Patológica/inducido químicamente , Adenocarcinoma/metabolismo , Animales , Línea Celular Tumoral , Femenino , Humanos , Neoplasias Mamarias Experimentales/metabolismo , Ratones Endogámicos BALB C , Ratones Desnudos , Recurrencia Local de Neoplasia/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Periodo Posoperatorio , Proteínas Proto-Oncogénicas c-myc/metabolismo , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Ecotoxicol Environ Saf ; 179: 160-166, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31039458

RESUMEN

Non-selective cation channels (NSCCs) play important roles in uptake of heavy metals in plants. However, little information is available concerning the contribution of NSCCs to cadmium (Cd) transport in rice seedlings. Results from the hydroponic experiment showed that the inhibition of 2.7 µM Cd on the development of rice roots was alleviated by adding 0.1 mM gadolinium (Gd) in nutrient solution, companied by reduction of Cd content by 55.3% in roots and by 45.0% in shoots. Inhibition of Gd on Cd accumulation in cytoplasm fraction (F3) was much greater than that in cell walls (F1) and organelles (F2) in roots. After increasing concentrations of Mn and Zn in nutrient solution, adding 0.1 mM Gd resulted in reductions in Cd content by 89.1%, in micronutrients by 54.9% and in macronutrients by 5.4% in roots, respectively. Cd stress resulted in significant increase of PC2∼4 and free amino acids, but decrease of V-ATPase activity by 32.3% in roots. These results indicate that NSCCs make a great contribution to uptake of Cd in rice seedlings and opportunities for Cd to be transported by NSCCs can be efficiently reduced by blocking NSCCs and/or increasing essential microelements like Mn and Zn.


Asunto(s)
Cadmio/metabolismo , Gadolinio/farmacología , Canales Iónicos/antagonistas & inhibidores , Transporte Iónico/efectos de los fármacos , Oryza/metabolismo , Plantones/metabolismo , Hidroponía , Oryza/efectos de los fármacos , Oryza/crecimiento & desarrollo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo
18.
Ecotoxicol Environ Saf ; 184: 109640, 2019 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-31499448

RESUMEN

Altering Cd chemical form is one of the mechanisms to alleviate Cd toxicity in rice plant. Field experiments were carried out in this study to investigate the potential of rice vegetative organs in altering Cd into insoluble chemical forms in the natural environment. Experimental results showed that more than 80% of Cd in rice roots existed in the insoluble forms. Uppermost nodes altered Cd into insoluble form preferentially and generally had higher content of insoluble Cd than other organs. Rachises displayed a slow increasing trend in soluble Cd when total Cd in roots was less than 1.8 mg kg-1. However, when Cd content in roots exceeded 2.8 mg kg-1, the ratio of insoluble to soluble Cd remained stable at 85:15 in rachises and roots, and at 75:25 in uppermost nodes and flag leaves. Cd concentration in grains was greatly lower than that in vegetative organs, and closely correlated with the content of soluble Cd in rachises (r = 0.991**) as well as in uppermost nodes. Soluble Cd in the uppermost nodes displayed a much lower mobility than that in other organs. Accumulation of soluble Cd was always companied by decrease of Ca and increase of Mn in roots, uppermost nodes and rachises. A small increase of soluble Cd from 0.05 to 0.1 mg kg-1 caused a sharp decline of Ca:Mn ratio in roots and rachises. Roots and nodes had much higher Ca:Mn ratio than rachises when soluble Cd was less than 0.5 mg kg-1 in them. These results indicate that vegetative organs have a great potential to alter more than 75% Cd into insoluble forms and increasing Ca:Mn ratio may be another way to alleviate Cd toxicity by establishing new ionic homeostasis in rice plants.


Asunto(s)
Cadmio/toxicidad , Calcio/análisis , Manganeso/análisis , Oryza/efectos de los fármacos , Cadmio/química , Grano Comestible/química , Grano Comestible/efectos de los fármacos , Modelos Teóricos , Oryza/química , Hojas de la Planta/química , Hojas de la Planta/efectos de los fármacos , Raíces de Plantas/química , Raíces de Plantas/efectos de los fármacos , Solubilidad
19.
J Basic Microbiol ; 58(12): 1083-1090, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30240023

RESUMEN

A new actinobacteria Streptomyces cavourensis TJ430 was isolated from the mountain soil collected from the southwest of China. In previous study, TJ430 showed striking bactericidal activities and strong ability of antibiotic production. Here, we report complete genome of this bacterium, consisting of 7.6 Mb linear chromosome and 0.2 Mb plasmids. It was predicted 6450 genes in chromosome and 225 genes in plasmids, as well as 12 gene islands in chromosome. Abundant genes have predicted functions in antibiotic metabolism and stress resistance. A whole-genome comparison of S. cavourensis TJ430, S. coelicolor A3(2), and S. lividans 66 indicates that TJ430 has a relatively high degree of strain specificity. The 16S rRNA phylogenetic tree shows the high identities (99.79%) of TJ430 with S. cavourensis DSM40300. TJ430 is a new and rare Streptomyces species, and analysis of its genome helps us to better understand primary metabolism mechanism of this isolate, as well as the evolutionary biology.


Asunto(s)
Genoma Bacteriano/genética , Microbiología del Suelo , Streptomyces/genética , Composición de Base , Secuencia de Bases , China , Farmacorresistencia Bacteriana/genética , Genes Bacterianos , Tamaño del Genoma , Islas Genómicas , Anotación de Secuencia Molecular , Filogenia , Plásmidos/genética , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Streptomyces/clasificación
20.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 35(4): 518-523, 2018 08 25.
Artículo en Zh | MEDLINE | ID: mdl-30124013

RESUMEN

The directed functional connectivity in cerebral cortical is the key to understanding the pattern of the behavioral tissue. This process was studied to explore the directed functional network of rifle shooters at cerebral cortical rhythms from electroencephalogram (EEG) data, aiming to provide neurosciences basis for the future development of accelerating rifle skill learning method. The generalized orthogonalized partial directed coherence (gOPDC) algorithm was used to calculate the effective directed functional connectivity of the experts and novices in the pre-shot period. The results showed that the frontal, frontal-central, central, parietal and occipital regions were activated. Moreover, the more directed functional connections numbers in right hemispheres were observed compared to the left hemispheres. Furthermore, as compared to experts, novices had more activated regions, the stronger strength of connections and the lower value of the global efficiency during the pre-shot period. Those indirectly supported the conclusion that the novices needed to recruit more brain resources to accomplish tasks, which was consistent with "neural efficiency" hypothesis of the functional cerebral cortical in experts.

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