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1.
Plant J ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38985498

RESUMEN

ERFs (ethylene-responsive factors) are known to play a key role in orchestrating cold stress signal transduction. However, the regulatory mechanisms and target genes of most ERFs are far from being well deciphered. In this study, we identified a cold-induced ERF, designated as PtrERF110, from trifoliate orange (Poncirus trifoliata L. Raf., also known as Citrus trifoliata L.), an elite cold-hardy plant. PtrERF110 is a nuclear protein with transcriptional activation activity. Overexpression of PtrERF110 remarkably enhanced cold tolerance in lemon (Citrus limon) and tobacco (Nicotiana tabacum), whereas VIGS (virus-induced gene silencing)-mediated knockdown of PtrERF110 drastically impaired the cold tolerance. RNA sequence analysis revealed that PtrERF110 overexpression resulted in global transcriptional reprogramming of a range of stress-responsive genes. Three of the genes, including PtrERD6L16 (early responsive dehydration 6-like transporters), PtrSPS4 (sucrose phosphate synthase 4), and PtrUGT80B1 (UDP-glucose: sterol glycosyltransferases 80B1), were confirmed as direct targets of PtrERF110. Consistently, PtrERF110-overexpressing plants exhibited higher levels of sugars and sterols compared to their wild type counterparts, whereas the VIGS plants had an opposite trend. Exogenous supply of sucrose restored the cold tolerance of PtrERF110-silencing plants. In addition, knockdown of PtrSPS4, PtrERD6L16, and PtrUGT80B1 substantially impaired the cold tolerance of P. trifoliata. Taken together, our findings indicate that PtrERF110 positively modulates cold tolerance by directly regulating sugar and sterol synthesis through transcriptionally activating PtrERD6L16, PtrSPS4, and PtrUGT80B1. The regulatory modules (ERF110-ERD6L16/SPS4/UGT80B1) unraveled in this study advance our understanding of the molecular mechanisms underlying sugar and sterol accumulation in plants subjected to cold stress.

2.
BMC Plant Biol ; 24(1): 617, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38937686

RESUMEN

BACKGROUND: Ichang papeda (Citrus ichangensis), a wild perennial plant of the Rutaceae family, is a cold-hardy plant. WRKY transcription factors are crucial regulators of plant growth and development as well as abiotic stress responses. However, the WRKY genes in C. ichangensis (CiWRKY) and their expression patterns under cold stress have not been thoroughly investigated, hindering our understanding of their role in cold tolerance. RESULTS: In this study, a total of 52 CiWRKY genes identified in the genome of C. ichangensis were classified into three main groups and five subgroups based on phylogenetic analysis. Comprehensive analyses of motif features, conserved domains, and gene structures were performed. Segmental duplication plays a significant role in the CiWRKY gene family expansion. Cis-acting element analysis revealed the presence of various stress-responsive elements in the promoters of the majority of CiWRKYs. Gene ontology (GO) analysis and protein-protein interaction predictions indicate that the CiWRKYs exhibit crucial roles in regulation of both development and stress response. Expression profiling analysis demonstrates that 14 CiWRKYs were substantially induced under cold stress. Virus-induced gene silencing (VIGS) assay confirmed that CiWRKY31, one of the cold-induced WRKYs, functions positively in regulation of cold tolerance. CONCLUSION: Sequence and protein properties of CiWRKYs were systematically analyzed. Among the 52 CiWRKY genes 14 members exhibited cold-responsive expression patterns, and CiWRKY31 was verified to be a positive regulator of cold tolerance. These findings pave way for future investigations to understand the molecular functions of CiWRKYs in cold tolerance and contribute to unravelling WRKYs that may be used for engineering cold tolerance in citrus.


Asunto(s)
Citrus , Respuesta al Choque por Frío , Regulación de la Expresión Génica de las Plantas , Filogenia , Proteínas de Plantas , Factores de Transcripción , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Citrus/genética , Citrus/fisiología , Respuesta al Choque por Frío/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Perfilación de la Expresión Génica , Genes de Plantas , Frío
3.
Ultrasonics ; 129: 106915, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36584656

RESUMEN

Phased array-based full-matrix ultrasonic imaging has been the golden standard for the non-destructive evaluation of critical components. However, the piezoelectric phased array cannot be applied in hazardous environments and online monitoring due to its couplant requirement. The laser ultrasonic technique can readily address these challenging tasks via fully non-contact inspection, but low detection sensitivity and complicated wave mode conversion hamper its practical applications. The laser-induced full-matrix ultrasonic imaging of complex defects was displayed in this study. Full matrix data acquisition and deep learning method were adapted to the laser ultrasonic technique to overcome the existing challenges. For proof-of-concept demonstrations, simulations and experiments were conducted on an aluminum sample with representative defects. Numerical and experimental results showed good agreement, revealing the excellent imaging performance of proposed method. Compared with the total focusing method based on ray-trace model, the deep learning method could create superior images with additional quantitative information through end-to-end networks, which use the hierarchical features and generate details from all the relevant imaging and physical characteristics information. The proposed method may help assess defect formation and development at the early stage in a hazardous environment and understand the in-situ manufacturing process due to its couplant-free nature.


Asunto(s)
Aprendizaje Profundo , Ultrasonido , Aluminio , Rayos Láser , Prueba de Estudio Conceptual
4.
Zhonghua Wei Chang Wai Ke Za Zhi ; 22(3): 262-266, 2019 Mar 25.
Artículo en Chino | MEDLINE | ID: mdl-30919379

RESUMEN

OBJECTIVE: To investigate the long-term outcome of laparoscope-assisted transanal total mesorectal excision (taTME) for rectal cancer. METHODS: Clinicopathological data of 29 patients with mid-low rectal cancer undergoing laparoscope-assisted taTME at Department of Gastrointestinal Surgery, the First Affiliated Hospital of Guangzhou Medical University from May 2010 to December 2015 were collected for the retrospective case-series study. All the operations were performed with transabdominal and transanal procedure simultaneously or sequentially. Perioperative presentations, pathological examinations, and oncologic outcomes were retrospectively analyzed. Long-term recurrence, metastasis and survival were assessed during follow-up. Outpatient clinic and telephone survey were used for follow-up. The follow-up time ended in December 2018. The overall survival (OS) rate and disease-free survival (DFS) rate were calculated by the Kaplan-Meier method. RESULTS: The average intra-operative blood loss was (75.9±9.5) ml (range,20 to 200). The average operating time was (223.6±4.1) minutes (range, 165 to 280). The average number of harvested lymph node was 22.3±2.0. The average length of pathological specimen was (13.1±0.6) cm. The average distal resection margin was (2.9±0.2) cm. 89.7% (26/29) of specimens was complete and 10.3% (3/29) near complete. Two cases (6.9%) had positive cutting circumferential margin. Median follow-up was 56 (range, 22 to 91) months. Local recurrence rate, distant metastasis rate, 3-year OS rate, 3-year DFS rate, 5-year OS rate, 5-year DFS rate were 10.3% (3/29), 20.7%(6/29), 96.6%, 83.2%, 87.6% and 79.6%, respectively. No incisional hernia or adhesive intestinal obstruction was found. CONCLUSION: Long-term outcomes of mid-low rectal cancer patients undergoing laparoscope-assisted taTME are satisfactory.


Asunto(s)
Neoplasias del Recto , Cirugía Endoscópica Transanal , Humanos , Laparoscopios , Recurrencia Local de Neoplasia , Neoplasias del Recto/cirugía , Recto , Estudios Retrospectivos
5.
Sci Rep ; 6: 19313, 2016 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-26763292

RESUMEN

Graphene deposited on various substrates has attracted the attention of the scientific and technical communities for use in a wide range of applications. Graphene on substrates is commonly produced by two types of methods, namely, methods that require a transfer step and transfer-free methods. Compared with methods that require a transfer step, transfer-free methods have a simpler procedure and a lower cost. Thus, transfer-free methods have considerable potential to meet the industrial and commercial demands of production methods. However, some limitations of the current transfer-free methods must be overcome, such as the high temperatures encountered during production, the relatively long manufacturing times, incompatibilities for both rigid and flexible substrates, and an inability to extend the process to other two-dimensional (2-D) atomic crystals. In this work, a room-temperature rubbing method is developed for the rapid transfer-free production of defect-free polycrystalline graphene on rigid and flexible substrates. Starting with inexpensive commercially obtained graphite powder, mono- and few-layer graphene can be fabricated directly on various substrates, with an average production time of less than one minute (from raw graphite to graphene on the substrate). Importantly, this method can be extended to other 2-D atomic crystals.

6.
Gland Surg ; 5(6): 628-632, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28149810

RESUMEN

Glass-free three-dimensional (3D) endoscopic provide excellent depth perception without decreasing light quality and fog formation. Herein we report our first case-serial of trans-oral endoscopic thyroidectomy by means of our newly developed glasses-free 3D endoscopic system. Four patients with thyroid goiter undergone trans-oral glasses-free 3D endosocpic thyroidectomy were reviewed. Mean BMI of these patients was 20.98±2.91 kg/m2. The dominate nodule of the thyroid was no more than 5 cm in diameter in all patients. Operation duration was 189.00±39.14 min, and mean Intraoperative blood loss was 7.50±2.89 mL. No postoperative complications were observed. All patients were satisfied with the cosmetic result. The use of a glasses-free 3D system in trans-oral endoscopic thyroidectomy is safe and effective. The clear image casted to the surgeon can greatly facilitate precise surgical movement and reduce eye fatigue. Further comparative studies should be conducted to confirm our conclusions.

7.
Mol Clin Oncol ; 3(5): 1155-1159, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26623069

RESUMEN

With the increase in life expectancy, surgical intervention for colorectal cancer (CRC) is more frequently performed in elderly patients. This retrospective study was designed to compare short-term outcomes between laparoscopy-assisted colorectomy (LC) and open colorectomy (OC) in elderly patients with CRC. A total of 89 CRC patients aged ≥75 years undergoing LC were matched with 89 counterparts undergoing OC. The matching criteria included general information and preoperative status. The operative data and short-term postoperative outcomes were compared. Following analysis, patients in the LC and OC groups were comparable for the matching criteria. Compared with the OC group, the operative time was longer (P=0.046), but the estimated blood loss (P<0.001) and intraoperative transfusion (P=0.042) were less in the LC group. As regards short-term postoperative outcomes, the duration of postoperative hospital stay was shorter (P=0.001) and the incidence of wound complications was lower (P=0.044) with LC. The overall complication, other complications, reoperation and mortality rates were comparable between the two groups. In conclusion, considering the operative variables and short-term outcomes, LC is a safe procedure and appears to be superior to OC for elderly patients with CRC.

8.
Adv Mater ; 27(13): 2236-41, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25704400

RESUMEN

Electrocaloric nanocomposites simultaneously derive high electrocaloric strength from inorganic inclusions and high dielectric strength from the polymer matrix to display a pronounced electrocaloric effect (ECE). By designing the inorganic filler and polymer matrix, which are both relaxor ferroelectrics with the ambient-temperature phase transition and minimized hysteresis, a large ECE becomes accessible with high cooling efficiency over a broad temperature range at and near room temperature.

9.
Sci Rep ; 3: 2697, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24045289

RESUMEN

The functional layers of few-layer two-dimensional (2-D) thin flakes on flexible polymers for stretchable applications have attracted much interest. However, most fabrication methods are "indirect" processes that require transfer steps. Moreover, previously reported "transfer-free" methods are only suitable for graphene and not for other few-layer 2-D thin flakes. Here, a friction based room temperature rubbing method is proposed for fabricating different types of few-layer 2-D thin flakes (graphene, hexagonal boron nitride (h-BN), molybdenum disulphide (MoS2), and tungsten disulphide (WS2)) on flexible polymer substrates. Commercial 2-D raw materials (graphite, h-BN, MoS2, and WS2) that contain thousands of atom layers were used. After several minutes, different types of few-layer 2-D thin flakes were fabricated directly on the flexible polymer substrates by rubbing procedures at room temperature and without any transfer step. These few-layer 2-D thin flakes strongly adhere to the flexible polymer substrates. This strong adhesion is beneficial for future applications.

10.
Ann Surg ; 256(1): 39-52, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22664559

RESUMEN

OBJECTIVE: To evaluate the safety and efficacy of laparoscopy-assisted distal gastrectomy (LADG) in patients with early gastric cancer (EGC) to determine whether LADG is an acceptable alternative to open distal gastrectomy (ODG). BACKGROUND: LADG combined with less than D2 or D2 lymphadenectomy for EGC is still a controversial surgical intervention for its uncertain oncological safety and economic benefit. We conducted this systematic review and meta-analysis that included randomized control trials (RCTs) and non-RCTs of LADG versus ODG to evaluate whether the safety and efficacy of LADG in patients with EGC are equivalent to those of ODG. METHODS: A comprehensive search of PubMed, EMBASE, Cochrane Library, and China Knowledge Resource Integrated Database was performed. Eligible trials published between January 1, 1994, and December 31, 2010, were included in the study. Data synthesis and statistical analysis were carried out by RevMan 5.0 software. The quality of evidence was assessed by GRADEpro 3.2.2. RESULTS: Twenty-two studies with 3411 participants were included in this study. The mean number of lymph nodes retrieved in LADG was close to that retrieved in ODG (in the less than D2 resection: weighted mean difference [WMD] = -1.79; 95% confidence interval [95% CI], -5.78 to 2.19; P = 0.38; heterogeneity: P < 0.00001, I = 98%; and in the D2 resection: WMD = -1.53; 95% CI, -3.56 to 0.51; P = 0.14; heterogeneity: P = 0.23, I = 26%). The overall postoperative morbidity was significantly less in LADG than in ODG (relative risk = 0.58; 95% CI, 0.46-0.74; P < 0.00001; heterogeneity: P = 0.94, I = 0%). LADG reduced the intraoperative blood loss, postoperative analgesic consumption, and hospital duration, without increasing the total hospitalization costs and cancer recurrence rate. The long-term survival rate of patients undergoing LADG was similar to that of patients undergoing ODG. However, LADG was still a technically dependent and time-consuming procedure. Conversion rate of LADG was 0% to 2.94%. The reported reasons for conversion were bleeding, adhesion, and safety resection margin requirement. LIMITATIONS: : There were potential biases and significant heterogeneity in some clinical outcome measures in this study. Methodologically high-quality controlled clinical trials were sparse for this new surgical intervention. According to The Grading of Recommendations Assessment, Development and Evaluation approach, when assessing the safety and efficacy of LADG by comparing with those of ODG with the defined clinical outcomes in patients with EGC, the quality of the currently available clinical evidence was very low. CONCLUSIONS: LADG may be a technically feasible alternative for EGC when it is performed in experienced surgical centers in which patients undergoing LADG may benefit from the faster postoperative recovery. However, the currently available evidence cannot exclude the potential clinical benefits or harms, especially in the node-positive cases. Methodologically high-quality comparative studies are needed for further evaluation.


Asunto(s)
Gastrectomía/métodos , Laparoscopía , Neoplasias Gástricas/cirugía , Pérdida de Sangre Quirúrgica/estadística & datos numéricos , Ensayos Clínicos como Asunto , Flatulencia/epidemiología , Hospitalización/economía , Humanos , Morbilidad , Recurrencia Local de Neoplasia/epidemiología , Factores de Tiempo , Resultado del Tratamiento
11.
Braz. j. med. biol. res ; 45(1): 78-85, Jan. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-610543

RESUMEN

Research on molecular mechanisms of carcinogenesis plays an important role in diagnosing and treating gastric cancer. Metabolic profiling may offer the opportunity to understand the molecular mechanism of carcinogenesis and help to non-invasively identify the potential biomarkers for the early diagnosis of human gastric cancer. The aims of this study were to explore the underlying metabolic mechanisms of gastric cancer and to identify biomarkers associated with morbidity. Gas chromatography/mass spectrometry (GC/MS) was used to analyze the serum metabolites of 30 Chinese gastric cancer patients and 30 healthy controls. Diagnostic models for gastric cancer were constructed using orthogonal partial least squares discriminant analysis (OPLS-DA). Acquired metabolomic data were analyzed by the nonparametric Wilcoxon test to find serum metabolic biomarkers for gastric cancer. The OPLS-DA model showed adequate discrimination between cancer and non-cancer cohorts while the model failed to discriminate different pathological stages (I-IV) of gastric cancer patients. A total of 44 endogenous metabolites such as amino acids, organic acids, carbohydrates, fatty acids, and steroids were detected, of which 18 differential metabolites were identified with significant differences. A total of 13 variables were obtained for their greatest contribution in the discriminating OPLS-DA model [variable importance in the projection (VIP) value >1.0], among which 11 metabolites were identified using both VIP values (VIP >1) and the Wilcoxon test. These metabolites potentially revealed perturbations of glycolysis and of amino acid, fatty acid, cholesterol, and nucleotide metabolism of gastric cancer patients. These results suggest that gastric cancer serum metabolic profiling has great potential in detecting this disease and helping to understand its metabolic mechanisms.


Asunto(s)
Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Persona de Mediana Edad , Metaboloma , Neoplasias Gástricas/sangre , Biomarcadores de Tumor/sangre , Adenocarcinoma , Estudios de Casos y Controles , Cromatografía de Gases y Espectrometría de Masas , Estadificación de Neoplasias , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patología
12.
Braz J Med Biol Res ; 45(1): 78-85, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22124703

RESUMEN

Research on molecular mechanisms of carcinogenesis plays an important role in diagnosing and treating gastric cancer. Metabolic profiling may offer the opportunity to understand the molecular mechanism of carcinogenesis and help to non-invasively identify the potential biomarkers for the early diagnosis of human gastric cancer. The aims of this study were to explore the underlying metabolic mechanisms of gastric cancer and to identify biomarkers associated with morbidity. Gas chromatography/mass spectrometry (GC/MS) was used to analyze the serum metabolites of 30 Chinese gastric cancer patients and 30 healthy controls. Diagnostic models for gastric cancer were constructed using orthogonal partial least squares discriminant analysis (OPLS-DA). Acquired metabolomic data were analyzed by the nonparametric Wilcoxon test to find serum metabolic biomarkers for gastric cancer. The OPLS-DA model showed adequate discrimination between cancer and non-cancer cohorts while the model failed to discriminate different pathological stages (I-IV) of gastric cancer patients. A total of 44 endogenous metabolites such as amino acids, organic acids, carbohydrates, fatty acids, and steroids were detected, of which 18 differential metabolites were identified with significant differences. A total of 13 variables were obtained for their greatest contribution in the discriminating OPLS-DA model [variable importance in the projection (VIP) value >1.0], among which 11 metabolites were identified using both VIP values (VIP >1) and the Wilcoxon test. These metabolites potentially revealed perturbations of glycolysis and of amino acid, fatty acid, cholesterol, and nucleotide metabolism of gastric cancer patients. These results suggest that gastric cancer serum metabolic profiling has great potential in detecting this disease and helping to understand its metabolic mechanisms.


Asunto(s)
Biomarcadores de Tumor/sangre , Metaboloma , Neoplasias Gástricas/sangre , Adenocarcinoma , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patología
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