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1.
Nanoscale ; 11(5): 2179-2185, 2019 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-30346003

RESUMEN

Newly emerging two-dimensional transition metal dichalcogenide HfS2 has received considerable attention recently due to its ultrahigh photoresponsivity, well-balanced carrier mobility and an appropriate band gap which offer potential in electronic and optoelectronic devices. In this work, HfS2 flakes up to 200 layers with varying color contrasts are fabricated and transferred on a SiO2/Si substrate. The Raman intensities of HfS2 flakes and Raman intensities of molecules adsorbed on HfS2 flakes are quantitatively studied both theoretically and experimentally by considering an optical interference effect. The effects of the main experimental factors: thickness of SiO2 and excitation wavelength on Raman intensities are also theoretically investigated. Due to the low absorption of HfS2, many strong high-order interference-induced enhancement peaks are observed which are different from high absorption materials like graphene and MoS2, in which only 2-4 interference-induced enhancement peaks exist. Due to the environmental instability of single layer HfS2 under ambient conditions, multi-layer HfS2 is a better choice than single layer HfS2 as a Raman scattering substrate which has a stronger Raman enhancement and a better environmental stability. The discovery here will expand the application of HfS2 flakes in molecular detection.

2.
Zhongguo Zhong Yao Za Zhi ; (24): 2714-2719, 2020.
Artículo en Zh | WPRIM | ID: wpr-828026

RESUMEN

To breed new varieties of medicinal plants with high resistance is the premise to ensure the production of high-quality medicinal materials. Molecular breeding using modern molecular biology and genetic technology can save time and effort and realize rapid and accurate breeding. Here we are trying to summarize the difference of breeding characteristics between medicinal plants and crops such as genetic background and breeding purpose. The strategy of molecular breeding of medicinal plants was summarized, and the four-phases breeding based on high-throughput sequencing and target gene mining was emphasized. We put forward the current molecular breeding of medicinal plants in the condition of four phases breeding is the optimal technological way of breeding, and gene editing breeding is the direction of medicinal plants breeding.


Asunto(s)
Cruzamiento , Barajamiento de ADN , Edición Génica , Fitomejoramiento , Plantas Medicinales , Genética
3.
Zhongguo Zhong Yao Za Zhi ; (24): 5577-5588, 2020.
Artículo en Zh | WPRIM | ID: wpr-878817

RESUMEN

Unraveling the genetic basis of medicinal plant metabolism and developmental traits is a long-standing goal for pharmacologists and plant biologists. This paper discusses the definition of molecular genetics of medicinal plants, which is an integrative discipline with medicinal plants as the research object. This discipline focuses on the heredity and variation of medicinal plants, and elucidates the relationship between the key traits of medicinal plants(active compounds, yield, resistance, etc.) and genotype, studies the structure and function, heredity and variation of medicinal plant genes mainly at molecular level, so as to reveal the molecular mechanisms of transmission, expression and regulation of genetic information of medicinal plants. Specifically, we emphasize on three major aspects of this discipline.(1)Individual and population genetics of medicinal plants, this part mainly highlights the genetic mechanism of the domestication, the individual genomics at the species level, and the formation of genetic diversity of medicinal plants.(2)Elucidation of biosynthetic pathways of active compounds and their evolutionary significance. This part summarizes the biosynthesis, diversity and molecular evolution of active compounds in medicinal plants.(3) Molecular mechanisms that shaping the key agronomic traits by internal and external factors. This part focuses on the accumulation and distribution of active compounds within plants and the regulation of metabolic network by environmental factors. Finally, we prospect the future direction of molecular genetics of medicinal plants based on the rapid development of multi-omics technology, as well as the application of molecular genetics in the future strategies to achieve conservation and breeding of medicinal plants and efficient biosynthesis of active compounds.


Asunto(s)
Vías Biosintéticas , Genómica , Biología Molecular , Fitomejoramiento , Plantas Medicinales
4.
Artículo en Zh | WPRIM | ID: wpr-816350

RESUMEN

OBJECTIVE: To evaluate the application of three-dimensional visualization technique in total mesopancreas excision(TMpE) for pancreatic head carcinoma. METHODS: From January 2013 to June 2017, 105 TMpE for pancreatic head carcinoma were performed in our institution, and clinical data of these cases were analyzed retrospectively. In order to evaluate the feasibility of operation, three-dimensional visualization techniques were applied to observe the site and size of the pancreatic head tumors, and the relationship between the tumors and peripancreatic vessels before the operation. RESULTS: The median operation time was 239 minutes, and the median blood loss was 409 mL. 29 cases with postoperative complications and no perioperative deaths. 74 patients were considered as R0 resection in final threedimensional pathologic examination, and the rate of R0 resection is 70.5%. CONCLUSION: Preoperative application of three-dimensional visualization technique in TMpE can improve preoperative assessment accuracy and increase the rate of R0 resection, in addition to reduce postoperative complications.

5.
Zhongguo Zhong Yao Za Zhi ; (24): 2421-2432, 2019.
Artículo en Zh | WPRIM | ID: wpr-773243

RESUMEN

With the development of various biotechnology,the research on molecular genetics of medicinal plants has gradually deepened. In this paper,the research system of molecular genetics of medicinal plants was proposed for the first time,which was elaborated from the aspects of genetic resources,genome,gene function and research methods. The application fields of medicinal plant mainly contain species identification,molecular breeding and biosynthesis. The research directions of molecular genetics of medicinal plants in genetic resources,model platform,synthetic biology and molecular breeding were put forward,which include 1 000 genome projects of medicinal plants,model species and mutant libraries,gene original libraries of heterologous synthetic systems,construction gene original library and specific chassis cells in heterologous synthesis system of active ingredient,breeding of new varieties of medicinal plants with high active ingredient and high resistance based on molecular markers andtransgenes.


Asunto(s)
Biotecnología , Biblioteca de Genes , Marcadores Genéticos , Genoma de Planta , Biología Molecular , Fitomejoramiento , Plantas Medicinales , Genética , Investigación , Transgenes
6.
Artículo en Zh | WPRIM | ID: wpr-668178

RESUMEN

BACKGROUND: Previous studies have found that electroacupuncture (EA) could effectively inhibit the expression of p38 and Fas mRNA mediated by MAPK signaling pathways, to further inhibit the apoptosis of chondrocytes. Meanwhile,EA delays the degeneration of articular cartilage mediated by JAK-STAT signaling pathway through upregulating the expression levels of transforming growth factor β1 as well as the mRNA expression levels of STAT3, Smad3 and LepR.OBJECTIVE: To explore the effect of EA on the cartilage ultrastructure and mRNA expression levels of Ras, Raf,MEK1/2 and ERK1/2 in the rat with knee osteoarthritis.METHODS: The rat models of knee osteoarthritis were established, and randomized into four groups at 2 weeks after modeling: model group received no interventions; 15- and 30-minute EA groups were given EA at the Hsiyen (medical,extra) of bilateral knee joints for 15 and 30 minutes, respectively; PD98059 group was given the intravenous injection of extracellular signal-regulated kinase inhibitor PD98059. The intervention time was 3 months. Those rats received normal feeding served as blank control group.RESULTS AND CONCLUSION: Transmission electron microscopy showed that compared with the model group, the chondrocytes in the 15- and 30-minute EA and PD98059 groups changed little, the nucleus was larger, partial endoplasmic reticulum cisterna expanded, and the mitochondria structure was clear. ELISA results showed that the 15-and 30-minute EA and PD98059 groups had a significant decrease in the level of tumor necrosis factor α compared with the model group (P < 0.01). RT-PCR revealed that the mRNA expression levels of Ras, Raf, MEK1/2 and ERK1/2 in the 15- and 30-minute EA and PD98059 groups were significantly downregulated (P < 0.05 or P < 0.01). These results indicate that EA can alleviate chondrocyte injury in the rat osteoarthritic model, reduce the level of tumor necrosis factor α in the synovium, and downregulated the expression levels of Ras, Raf, MEK1/2 and ERK1/2 mRNA, further delaying the chondrocyte degeneration in osteoarthritis.

7.
Zhonghua Wai Ke Za Zhi ; (12): 1067-1070, 2013.
Artículo en Zh | WPRIM | ID: wpr-314765

RESUMEN

<p><b>OBJECTIVE</b>To study the relationship between the change of coagulation and the clinicopathologic characteristics in patients with gallbladder cancer.</p><p><b>METHODS</b>The 64 gallbladder cancer patients (GBC group) and 60 cholecystitis patients (control group) had been reviewed from January 2007 to June 2013. The prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (Fib), and thrombin time (TT) had been measured and compared between patients of GBC group and control group. The relationship of coagulation function and prognosis were analyzed.</p><p><b>RESULTS</b>Compared with control group, APTT in GBC group ((29.0 ± 4.2) s) was significantly shortened (t = -4.265, P = 0.000) and PT ((11.5 ± 1.4) s), TT ((15.3 ± 3.5) s), Fib ((4.1 ± 0.9) g/L) were significantly increased in GBC group (t = 2.521, 4.147 and 4.365, all P < 0.05). The level of Fib was higher in patients with medium or poor-differentiated tumor cells (F = 4.069, P = 0.022), lymph metastasis (t = 2.640, P = 0.010) and advanced staging (II-IV) (t = 3.003, P < 0.01) than those of well-differentiated, non-lymph metastasis and early staging (0-I). The ratio of gallbladder cancer with hyperfibrinogenemia (32/64) was significantly higher than control group (11/60, χ(2) = 13.709, P < 0.01). In GBC group, compared with normal Fib patients, hyperfibrinogenemia patients showed significantly difference in clinicopathologic characteristics (χ(2) = 5.851-10.573, P < 0.05). The average survival period of hyperfibrinogenemia patients and normal Fib patients were 8.63 months and 16.73 months. The 1-, 3-year survival rate of patients with hyperfibrinogenemia were significantly lower than those with normal Fib (64.7%, 14.9% vs. 74.9%, 21.1%, P < 0.05).</p><p><b>CONCLUSION</b>Preoperative plasma level of Fib might be a new promising biomarker in patients with gallbladder cancer for evaluating disease progression and prognosis.</p>


Asunto(s)
Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Coagulación Sanguínea , Estudios de Casos y Controles , Fibrinógeno , Metabolismo , Neoplasias de la Vesícula Biliar , Pronóstico , Tiempo de Protrombina
8.
Zhonghua Wai Ke Za Zhi ; (12): 780-783, 2013.
Artículo en Zh | WPRIM | ID: wpr-301213

RESUMEN

<p><b>OBJECTIVE</b>To evaluate the effect of preoperative transarterial chemoembolization (TACE) on hepatocellular carcinoma located in caudate lobe.</p><p><b>METHODS</b>Totally 29 cases of caudate lobe hepatocellular carcinoma admitted from January 2001 to December 2010 were analyzed retrospectively. Among the 29 patients, 23 were male and the other 6 were female. The median age was 52 years. According to receiving preoperative TACE or not, the 29 cases were divided into two groups: preoperative TACE plus surgery (group A, n = 11) and surgery only (group B, n = 18). The surgical results and long-term survival were compared between two groups.</p><p><b>RESULTS</b>After TACE, the diameter of the tumour reduced by over 33.3% in 3 patients, 10.0% to 33.3% in 6 patients, and less than 10.0% in 2 patients. The duration of surgery and intraoperative blood loss in group A were (298 ± 39) minutes and (1031 ± 310) ml, respectively. The duration of surgery and intraoperative blood loss in group B were (281 ± 54) minutes and (868 ± 403) ml, respectively. No significant difference was found in terms of these two groups (t = 1.006, P = 0.324; t = 1.223, P = 0.232). In addition, 6 cases in group A developed complications and 4 cases in group B did so. Only one patient died because of postoperative complication, and this patient belonged to group A. No significant difference was found between two groups (χ(2) = 0.028, P = 0.868; χ(2) = 0.633, P = 0.426). The 5-year survival rate was 56.8% in group A and 34.9% in group B. The difference did not reach significant difference (P = 0.132).</p><p><b>CONCLUSIONS</b>For hepatocellular carcinoma located in caudate lobe, preoperative TACE does not significantly increase the surgical difficulty and impair the safety. In addition, preoperative TACE has the tendency to provide benefit to long-term survival.</p>


Asunto(s)
Humanos , Carcinoma Hepatocelular , Cirugía General , Quimioembolización Terapéutica , Hepatectomía , Neoplasias Hepáticas , Cirugía General , Estudios Retrospectivos
9.
Artículo en Zh | WPRIM | ID: wpr-321580

RESUMEN

Gastric cancer is one of the most serious health problems in China. The overall survival rate after surgical treatment has increased and the rate of postoperative complication has decreased. These improvements are due to the introduction of more radical surgical techniques, early detection, and the improvement of anesthesia, perioperative care, and nutritional support. The aim of this article is to introduce the general perioperative management of patients with gastric cancer. Good perioperative management of gastric cancer contributes to the improvement of surgical outcomes. There are several controversial issues in the general perioperative management of gastric cancer, such as gastric tube decompression and nutritional support.


Asunto(s)
Humanos , Atención Perioperativa , Métodos , Neoplasias Gástricas , Cirugía General
10.
Chin. med. j ; Chin. med. j;(24): 1777-1783, 2012.
Artículo en Inglés | WPRIM | ID: wpr-324894

RESUMEN

<p><b>BACKGROUND</b>Gastric cancer ranks high among the most common causes of cancer-related death worldwide. This study was designed to explore key genes involved in the progression of normal gastric epithelial cells to moderate gastric epithelial dysplasia (mGED) and to gastric cancer.</p><p><b>METHODS</b>Twelve pairs of mGED tissues, gastric cancer tissues, and normal gastric tissues were collected by gastroscopy. Total RNA was then extracted and purified. After the addition of fluorescent tags, hybridization was carried out on a Gene chip microarray slide. Significance analysis of microarrays was performed to determine significant differences in gene expression between the different tissue types.</p><p><b>RESULTS</b>Microarray data analysis revealed totally 34 genes that were expressed differently: 18 highly expressed (fold change > 2; P < 0.01) and 16 down-regulated (fold change > 2; P < 0.01). Of the 34 genes, 24 belonged to several different functional categories such as structural molecule activity, extracellular regions, structural formation, cell death, biological adhesion, developmental processes, locomotion, and biological regulation that were associated with cancer. The remaining 10 genes were not involved in cancer research. Of these genes, the expression levels of Matrix metalloproteinase-12 (MMP12), Caspase-associated recruitment domain 14 (CARD14), and Chitinase 3-like 1 (CHI3L1) were confirmed by semi-quantitative RT-PCR. A two-way clustering algorithm divided the 36 samples into three categories and the overall correct classification efficiency was 80.6% (29/36). Almost all of these genes (31/34) showed constant changes in the process of normal gastric epithelial cells to mGED to gastric cancer.</p><p><b>CONCLUSIONS</b>The results of this study provided global gene expression profiles during the development and progression from normal gastric epithelial cells to mGED to gastric cancer. These data may provide new insights into the molecular pathology of gastric cancer which may be useful for the detection, diagnosis, and treatment.</p>


Asunto(s)
Adulto , Anciano , Humanos , Persona de Mediana Edad , Células Epiteliales , Metabolismo , Mucosa Gástrica , Metabolismo , Patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estómago , Metabolismo , Patología , Neoplasias Gástricas , Genética , Transcriptoma , Genética
11.
Chin. med. j ; Chin. med. j;(24): 4236-4244, 2011.
Artículo en Inglés | WPRIM | ID: wpr-333580

RESUMEN

<p><b>BACKGROUND</b>The precise molecular mechanisms underlying the gallbladder carcinoma (GBC) metastasis has not been fully elucidated.</p><p><b>METHODS</b>In the present study, metastasis-associated proteins were identified by comparative proteomic analysis. The functional study of the candidate protein vimentin was further investigated. First, a pair of higher and lower metastatic sublines (termed GBC-SD/M3 and GBC-SD, respectively), originated from the same parental cell line, was screened by spontaneous tumorigenicity and metastasis in vivo in animal study and further characterized by metastatic phenotypes analysis in vitro. Subsequently, a proteomic approach comprised two-dimensional gel electrophoresis analysis and mass spectroscopy was used to identify and compare the protein expression patterns between higher metastatic GBC-SD/M3 and lower metastatic GBC-SD cell lines. Then twenty-six proteins were identified.</p><p><b>RESULTS</b>Among the 26 proteins identified, fourteen proteins were up-regulated and 12 proteins were down-regulated in GBC-SD/M3. Vimentin was identified and found to be overexpressed in GBC-SD/M3 as compared with GBC-SD. This result was further confirmed by quantitative PCR and Western blotting analysis. Furthermore, the cell migration and invasion potency of GBC-SD/M3 in vitro was remarkably suppressed after small interference RNA-mediated knockdown of vimentin. Moreover, immunoblot and immunohistochemical analysis on 12 human GBC specimens showed consistently increased vimentin expression in metastases compared with primary tumors.</p><p><b>CONCLUSION</b>Tumor vimentin level may reflect the pathological progression in some GBC and may be a useful marker for predicting tumor metastasis and a therapeutic target for the treatment of GBC patients with metastases.</p>


Asunto(s)
Animales , Humanos , Ratones , Western Blotting , Línea Celular Tumoral , Movimiento Celular , Genética , Fisiología , Electroforesis en Gel Bidimensional , Neoplasias de la Vesícula Biliar , Genética , Metabolismo , Patología , Inmunohistoquímica , Ratones Desnudos , Metástasis de la Neoplasia , Genética , Patología , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Vimentina , Genética , Metabolismo
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