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1.
Sensors (Basel) ; 22(21)2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36365818

RESUMEN

Laser soldering has been gradually applied to the soldering of electronic components due to the rapid development of microelectronics. However, it is inefficient to use a mechanical shaft to move a laser beam. Here, a laser soldering system is constructed using galvanometer scanning, and an intelligent algorithm is also introduced to optimize the soldering path. Firstly, a laser soldering system for scanning of galvanometers is established, and the functions of visual monitoring, motion planning and parameter integration are presented. Secondly, the position of the laser beam and the corresponding soldering spot are determined, and the coordinate information is provided to plan a route by camera calibration and coordinate system transformation. Finally, the problem of path planning in this system is decomposed into the generation of the soldering point full coverage processing frame, and the route optimization of processing platform and laser beam motion. Furthermore, an improved clustering algorithm, based on the characteristics of system structure, and a hybrid optimization algorithm are designed to deal with the generation of the soldering point full coverage processing frame, the route optimization of processing platform and laser beam motion. In addition, the simulations and experiments are verified by test board. These findings shown that the established system and designed optimization algorithm can promote the efficiency of laser soldering.

2.
Physiol Mol Biol Plants ; 28(2): 439-454, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35400891

RESUMEN

Vicatia thibetica de Boiss.: a herb in the family Apiaceae, has been used for over a hundred years as an essential medicinal and edible plant in the Bai ethnic group of Dali City. However, due to the lack of study on plastid genomes of V. thibetica, studies of comparison and phylogeny with other related species remain scarce. In the current study, we assembled, annotated, and characterized the entire chloroplast (cp) genome of V. thibetica through high-throughput sequencing for the first time, compared with published whole chloroplast genomes from the same family. A phylogenetic analysis of the chloroplast genome has also been performed. The whole chloroplast genome of V. thibetica was 145,796 in size and consisted of a large single-copy region (LSC; 92,186 bp), a small single-copy region (SSC; 17,452 bp), and a pair of inverted repeat regions (IRs; 18,079 bp) forming a circular quadripartite structure. Annotation resulted in 128 genes, including 84 protein-coding genes (PCGs), 35 transfer RNA genes (tRNAs), eight ribosomal genes (rRNAs), and one pseudogene. Repeat sequence analysis displayed V. thibetica plastid genome contains 75 simple repeats, 37 long repeats, and 29 tandem repeats. Compared with the cp genome of other Apiaceae species, a common feature was that the IR regions of the genome were more conservative compared to the LSC and SSC regions. Highly variable hotspots included rps16, ndhC-trnV-UAC, clpP, ycf1, and ndhB in the genomes, which supply valuable molecular markers for phylogeny, identification, and classification in the Apiaceae family. The results of phylogenetic analysis strongly supported the genus Vicatia as an independent genus in the family Apiaceae, in which the closest affinities to the related species of Angelica, Peucedanum, and Ligusticum were observed. In conclusion, the first chloroplast genome of Vicatia reported in this study may  improve our understanding of phylogenetic relationship of different genera of Apiaceae. In addition, the current data will be valuable as chloroplast genomic resource for species identification and population genetics. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01154-y.

3.
J Sci Food Agric ; 99(9): 4430-4438, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30859570

RESUMEN

BACKGROUND: Drought is the most serious limiting factor of rice production worldwide and is becoming more intensive with climate change in recent years. Screening and breeding drought-tolerant rice genotypes are essential to maintain yield gain and ensure food security under adverse environments. However, thus far, little attention has been given to the temporal changes of drought resistance concomitant with the year of release in rice genetic breeding. RESULTS: Sixteen rice genotypes bred or widely cultivated from 1934 to 2007 were grown in paddy fields (control) and upland fields (drought stress) to explore the variation of drought resistance in rice genotypes with the year of release. Grain yield and daily grain yield significantly increased with the year of release. The genetic improvements in the grain yield partially resulted from the significant increase in panicle, spikelets per panicle and filling percentage. In addition, various growth-related characteristics like biomass, harvest index, relative growth rate, grain density and growth duration increased with an increase of genetic refinement of the genotypes through the years, and they contributed to improvement of final rice yields. However, grain yield, yield components and these growth-related traits sharply declined under drought stress. Furthermore, the drought resistance coefficients of KYield , KDaily grain yield , KPanicle number , KSpikelets per panicle , KBiomass , KPlant height , KRelative growth rate and KFilling percentage were prominently improved by genetic breeding. CONCLUSIONS: Drought resistance of rice genotypes has been significantly enhanced by genetic processes during the last 73 years in China, but they are still sensitive to drought conditions. Currently, there is still room for further improvement in drought resistance which is an important target in future breeding programs. © 2019 Society of Chemical Industry.


Asunto(s)
Oryza/fisiología , China , Sequías , Genotipo , Oryza/genética , Oryza/crecimiento & desarrollo , Fenotipo , Fitomejoramiento , Semillas/genética , Semillas/crecimiento & desarrollo , Semillas/fisiología
4.
Microbiol Res ; 288: 127839, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39141971

RESUMEN

The evolution of hypervirulent and carbapenem-resistant Klebsiella pneumoniae can be categorized into three main patterns: the evolution of KL1/KL2-hvKp strains into CR-hvKp, the evolution of carbapenem-resistant K. pneumoniae (CRKp) strains into hv-CRKp, and the acquisition of hybrid plasmids carrying carbapenem resistance and virulence genes by classical K. pneumoniae (cKp). These strains are characterized by multi-drug resistance, high virulence, and high infectivity. Currently, there are no effective methods for treating and surveillance this pathogen. In addition, the continuous horizontal transfer and clonal spread of these bacteria under the pressure of hospital antibiotics have led to the emergence of more drug-resistant strains. This review discusses the evolution and distribution characteristics of hypervirulent and carbapenem-resistant K. pneumoniae, the mechanisms of carbapenem resistance and hypervirulence, risk factors for susceptibility, infection syndromes, treatment regimens, real-time surveillance and preventive control measures. It also outlines the resistance mechanisms of antimicrobial drugs used to treat this pathogen, providing insights for developing new drugs, combination therapies, and a "One Health" approach. Narrowing the scope of surveillance but intensifying implementation efforts is a viable solution. Monitoring of strains can be focused primarily on hospitals and urban wastewater treatment plants.


Asunto(s)
Antibacterianos , Carbapenémicos , Infecciones por Klebsiella , Klebsiella pneumoniae , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/patogenicidad , Humanos , Infecciones por Klebsiella/microbiología , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/tratamiento farmacológico , Virulencia , Carbapenémicos/farmacología , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Enterobacteriaceae Resistentes a los Carbapenémicos/patogenicidad , Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Plásmidos/genética , Salud Pública , Salud Global , Factores de Virulencia/genética , Factores de Riesgo
5.
Heliyon ; 10(14): e34846, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39148993

RESUMEN

F. taipaiensis P. Y. Li represents a significant asset within traditional Chinese medicinal flora, though it confronts the challenge of germplasm deterioration during its cultivation phase. This study aimed to discern the implications of single strains or combinations of diverse growth-promoting actinomycetes on the growth metrics, antioxidant competence and pertinent gene expression in the leaves of F. taipaiensis. The result revealed that the malondialdehyde content within the plant's leaves notably diminished in the treatment groups compared to the CK group, with the S6 group showcasing the most pronounced malondialdehyde reduction, amounting to approximately one-third of the CK's value. Leaf area, length and width peaked in the S5 cohort, registering values 4.55, 2.46 and 1.85 times surpassing the CK group. Concurrently, plant height and stem thickness were maximal in the S6 group, being 2.29 and 1.75 times that of the CK group, whereas leaf thickness reached its zenith in the S7 group, marking a 2.17-fold elevation compared to the CK. Photosynthetic pigments, soluble sugars and soluble proteins in the leaves, exhibited augmentation across the inoculated groups to varying magnitudes. Specifically, the S5 group was superior in photosynthetic metrics and pigments, while the S6 group manifested the highest soluble sugar concentration, which was 1.35 times that of the CK. The S3 group demonstrated the pinnacle of soluble protein content, an impressive 5.86-fold increment relative to the CK group. The enzymatic activities of superoxide dismutase, peroxidase and catalase, along with their affiliated gene expressions, were observably augmented in the inoculated groups, with the S5 group standing out. To encapsulate, the actinomycete inoculation holds potential in fostering the growth and maturation of F. taipaiensis, amplifying its environmental resilience. The revelations from this study extend valuable insights for the judicious choice of microbial fertilizers in the cultivated propagation of Fritillaria taipaiensis P. Y. Li.

6.
Int J Biol Macromol ; 253(Pt 8): 127482, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37866586

RESUMEN

Spirulina has been widely used worldwide as a food and medicinal ingredient for centuries. Polysaccharides are major bioactive constituents of Spirulina and are of interest because of their functional properties and unlimited application potential. However, the clinical translation and market industrialization of the polysaccharides from genus Spirulina (PGS) are retarded due to the lack of a further understanding of their isolation, bioactivities, structure-activity relationships (SARs), toxicity, and, most importantly, versatile applications. Herein, we provide an overview of the extraction, purification, and structural features of PGS; meanwhile, the advances in bioactivities, SARs, mechanisms of effects, and toxicity are discussed and summarized. Furthermore, the applications, potential developments, and future research directions are scrutinized and highlighted. This review may help fill the knowledge gap between theoretical insights and practical applications and guide future research and industrial application of PGS.


Asunto(s)
Spirulina , Polisacáridos/química , Relación Estructura-Actividad
7.
Comb Chem High Throughput Screen ; 26(9): 1755-1765, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36173042

RESUMEN

BACKGROUND: Depression is a typical outcome of the repair of posttraumatic stress disorder (PTSD). Based on network pharmacology and neuropharmacology experiments, this study aimed to explore how gastrodin (GAS) reverses depressive symptoms in traumatically stressed rats. METHODS: GAS-related targets were predicted by SwissTargetPrediction; depression-related targets were collected from GeneCards and therapeutic target database (TTD); protein-protein interaction (PPI) network was constructed with its action mechanism being predicted by gene ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. The animal model of PTSD was replicated by single prolonged stress (SPS). The antidepressant effect of GAS was investigated by the forced swim test (FST) and tail suspension test (TST). The levels of tyrosine hydroxylase (TH) and corticotropin-releasing factor type I receptor (CRF1) in locus ceruleus (LC) and the expression of corticotropin-releasing factor (CRF) in the paraventricular nucleus of the hypothalamus (PVN) and central amygdala (CeA) were measured by immunofluorescence. RESULTS: GAS significantly shortened the tail suspension and swimming immobility in SPS rats in TST and FST experiments (p < 0.05 or p < 0.01). The network analysis showed that the critical antidepressant targets of GAS were 86 targets such as GAPDH, CASP3 MMP9, HRAS, DPP4, and TH, which were significantly enriched in the pathways such as pathways neuroactive ligandreceptor interaction. High doses of GAS could significantly reduce the level of TH and CRF in CEA in the brain of rats with depressive symptoms (p < 0.01) and, at the same time, lower the expression of CRF in PVN (p < 0.05). CONCLUSION: The effect of GAS on depressive symptoms in SPS rats may be closely related to its reduction of CRF expression in PVN and CeA and inhibition of neuron (NE) synthesis in LC.


Asunto(s)
Hormona Liberadora de Corticotropina , Depresión , Ratas , Animales , Hormona Liberadora de Corticotropina/genética , Hormona Liberadora de Corticotropina/metabolismo , Depresión/tratamiento farmacológico , Depresión/metabolismo , Farmacología en Red , Receptores de Hormona Liberadora de Corticotropina/genética , Receptores de Hormona Liberadora de Corticotropina/metabolismo , Antidepresivos/farmacología , Antidepresivos/uso terapéutico
8.
Plant Signal Behav ; 18(1): 2203571, 2023 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-37128906

RESUMEN

As a kind of medicinal plant, Peucedanum praeruptorum Dunn has been over-harvested in the wild population, which leads to its artificial cultivation. The present study aims to analyze the effects of different plant growth-promoting rhizobacteria (PGPR) on the growth and physiological characteristics of P. Praeruptorum leaves. Compared with the CK, the content of malondialdehyde (MDA) was drastically reduced in the leaves of P. Praeruptorum in different treatment groups (P < 0.05), and with S6 showing the most significant reduction in MDA content (content was only about 1/3 that of the CK). The indicators of leaf area, length and width were found to be the highest in group S9, reaching a level that is 3.75, 3.08 and 1.48 times higher than those in group CK, respectively. Group S8 has the largest plant height, which is 1.22 times higher than that in group CK. S2 has the largest stem diameter, which is 1.69 times higher than that in group CK. Group S1 has the largest petiole length, which is 1.74 times higher than that in group CK. Group S6 has the largest chlorophyll content, which is 1.63 times higher than that in group CK. Group S2 has the highest content of soluble sugar and soluble protein, which are 2.02 times and 3.82 times higher than those in group CK. Group S9 exhibits the strongest CAT activity, which is 3.71 times higher than that in group CK. S5 exhibits the strongest SOD activity, which is 2.32 times higher than group CK. Group S1 exhibits the strongest POD activity, which is 5.94 times higher than that in group CK. In conclusion, the inoculation with PGPR is effective in improving the growth of P. Praeruptorum leaves and their physiological indicators, which provides guidance on the application of PGPR to achieve the high quality and yield of P. Praeruptorum.


Asunto(s)
Hojas de la Planta , Hojas de la Planta/metabolismo
9.
Mitochondrial DNA B Resour ; 7(1): 115-117, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34993331

RESUMEN

Aconitum piepunense belonging to the family Ranunculaceae is an endangered herb species in southwestern China. In this study, the complete chloroplast genome of A. piepunense was sequenced, and the results revealed a typical quadripartite structure with a length of 155,836 bp, including a large single-copy region (LSC, 86,433 bp), a small single-copy region (SSC, 16,945 bp), and a pair of inverted repeat (IR) regions (IRa and IRb, 26,229 bp, respectively). A total of 130 genes were identified in the A. piepunense chloroplast genome, containing 85 protein-coding genes, 37 transfer RNA (tRNA) genes, and 8 ribosomal RNA (rRNA) genes. Phylogenetic analysis based on the maximum likelihood method indicated that A. piepunense formed a monophyletic group, which was sister to A. contortum and A. vilmorinianum.

10.
Mitochondrial DNA B Resour ; 7(6): 1165-1167, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35783038

RESUMEN

Aconitum forrestii Stapf is an essential traditional Chinese medicine, and is beneficial in dispelling wind, removing dampness, warming, and relieving pain. However, its phylogenetic position of Aconitum is not accepted yet. In order to clarify the evolutionary relationship of A. forrestii, complete sequencing of chloroplast genome was carried out using Illumina sequencing technology. In total, the chloroplast genome was about 155,869 base pair (bp) in length and carried a typical tetrad structure that included a large single-copy, a small-single copy and two inverted repeat regions. A total of 132 genes were annotated, that included 85 protein -coding genes, 37 transfer RNA genes, eight ribosomal RNA genes, and two pseudogenes. The phylogenetic tree analysis indicated that Aconitum forrestii is closely related to Aconitum episcopale and Aconitum delavayi.

11.
Bioorg Med Chem ; 19(19): 5776-81, 2011 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-21893415

RESUMEN

AMP-activated kinase (AMPK) as a key controller in the regulation of whole-body energy homeostasis, plays an important role in protecting the body from metabolic diseases. Recently, improved glucose, lipid utility and increased insulin sensitivity were observed on several diabetic rodent models treated with crude mogrosides isolated from the fruit of Siraitia grosvenorii Swingle, but the precise active compounds responsible for the anti-diabetic activity of this plant have not been clearly identified. In our current work, acid hydrolysis of crude mogrosides provided five new cucurbitane triterpenoids (1-4, 8), along with three known ones (5-7). The main aglycone mogrol (7) and compounds 4 and 8 were found to be potent AMPK activators in the HepG2 cell line. This result suggested AMPK activation by the mogroside aglycones 7 and 8 was proved to contribute at least partially to the anti-hyperglycemic and anti-lipidemic properties in vivo of S. grosvenorii.


Asunto(s)
Proteínas Quinasas Activadas por AMP/química , Cucurbitaceae/química , Activadores de Enzimas/química , Glicósidos/química , Hipoglucemiantes/química , Triterpenos/química , Proteínas Quinasas Activadas por AMP/metabolismo , Activación Enzimática/efectos de los fármacos , Activadores de Enzimas/aislamiento & purificación , Activadores de Enzimas/farmacología , Frutas/química , Glicósidos/aislamiento & purificación , Glicósidos/farmacología , Células Hep G2 , Humanos , Hipoglucemiantes/aislamiento & purificación , Hipoglucemiantes/farmacología , Triterpenos/aislamiento & purificación , Triterpenos/farmacología
12.
Steroids ; 159: 108650, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32360418

RESUMEN

A series of oleandrin-4'-yl ester derivatives were designed, synthesized, and evaluated for their proliferation inhibition activities against tumor cell lines. Cytotoxicity data revealed that the C4' moiety had an important influence on cytotoxic activity. Several compounds that we designed and synthesized exhibit significant in vitro antiproliferative activity against the tested tumor cell lines. Among the derivatives of OL, 4b-HCl not only had good anti-tumor activity but also had good water solubility. Furthermore, 4b-HCl can significantly inhibit tumor growth by 96.4% at a dose of 6 mg/kg/d by ip.


Asunto(s)
Antineoplásicos/farmacología , Cardenólidos/síntesis química , Cardenólidos/farmacología , Muerte Celular/efectos de los fármacos , Neoplasias Experimentales/patología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Cardenólidos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Conformación Molecular , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/metabolismo , Relación Estructura-Actividad
13.
Shanghai Kou Qiang Yi Xue ; 24(4): 460-4, 2015 Aug.
Artículo en Zh | MEDLINE | ID: mdl-26383572

RESUMEN

PURPOSE: To present a method for mandibular defects reconstruction with free fibular flap by three-dimensional virtual technology. METHODS: In 11 patients (8 with ameloblastomas, 1 with ossifying fibroma, 2 with carcinoma of the mandibular gingiva ), three-dimensional virtual technology was simulated with software. The osteotomies were translated into rapid prototyping guides. The solid model of the mandible and the surgical guides were the same as the full size and the shape, and made by using rapid prototyping machine. During operation, the bridging plate could be pre-bended on the repaired mandibular model. One group resected the diseased mandibular according to the model of the osteotomy which was planned before operation, the other group used auxiliary guide for accurate osteotomy of the fibula bone with contact pedicle. The fibular segments were reshaped and fixed with prefabricated titanium plate, and transplanted into the defect for vascular anastomosis. RESULTS: All the bone flaps and osteocutaneous flaps survived. During operation, the fibula flap could be cut in appropriate length. Cutting, remodeling and reposition of the fibula could be accelerated by surgery guides. Postoperative follow-up was 1 to 24 months. Imaging examination showed that the shape of mandible and mandibular angle were good, and the temporomandibular joint and occlusion returned to normal. CONCLUSIONS: Three-dimensional virtual technology is useful in reconstruction of mandibular defect with vascularized fibular flap.


Asunto(s)
Trasplante Óseo , Colgajos Tisulares Libres , Mandíbula/anomalías , Reconstrucción Mandibular/métodos , Ameloblastoma , Placas Óseas , Peroné , Humanos , Imagenología Tridimensional , Osteotomía , Programas Informáticos
14.
Fitoterapia ; 94: 88-93, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24462673

RESUMEN

Two new cucurbitane triterpenoids, 7ß-hydroxycucurbitacin F-25-O-acetate (1) and 2ß,3ß,20(S),26,27-pentahydroxy-16α,23(S)-epoxycucurbita-5,24-dien-11-one (2) along with eleven known cucurbitane triterpenoids (3-13, resp.) were isolated from the rhizomes of Hemsleya amabilis Diels. The chemical structures of the new isolated compounds were elucidated unambiguously by spectroscopic data analysis. The cytotoxic activities of the isolated cucurbitane triterpenoids were evaluated against the HeLa human cancer cell lines. Hemslecin A (5), the main ingredient of H. amabilis, exhibited the significant cytotoxicity with IC50 value of 0.389 µM.


Asunto(s)
Cucurbitaceae/química , Cucurbitacinas/química , Extractos Vegetales/química , Rizoma/química , Triterpenos/química , Alcaloides/química , Alcaloides/aislamiento & purificación , Alcaloides/farmacología , Supervivencia Celular/efectos de los fármacos , Cucurbitacinas/aislamiento & purificación , Cucurbitacinas/farmacología , Femenino , Células HeLa , Humanos , Concentración 50 Inhibidora , Espectroscopía de Resonancia Magnética , Estructura Molecular , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Plantas Medicinales , Triterpenos/aislamiento & purificación , Triterpenos/farmacología
15.
PLoS One ; 9(9): e108163, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25229628

RESUMEN

Spatial and temporal patterns of carbon (C) storage in forest ecosystems significantly affect the terrestrial C budget, but such patterns are unclear in the forests in Hainan Province, the largest tropical island in China. Here, we estimated the spatial and temporal patterns of C storage from 1993-2008 in Hainan's forest ecosystems by combining our measured data with four consecutive national forest inventories data. Forest coverage increased from 20.7% in the 1950s to 56.4% in the 2010s. The average C density of 163.7 Mg C/ha in Hainan's forest ecosystems in this study was slightly higher than that of China's mainland forests, but was remarkably lower than that in the tropical forests worldwide. Total forest ecosystem C storage in Hainan increased from 109.51 Tg in 1993 to 279.17 Tg in 2008. Soil C accounted for more than 70% of total forest ecosystem C. The spatial distribution of forest C storage in Hainan was uneven, reflecting differences in land use change and forest management. The potential carbon sequestration of forest ecosystems was 77.3 Tg C if all forested lands were restored to natural tropical forests. To increase the C sequestration potential on Hainan Island, future forest management should focus on the conservation of natural forests, selection of tree species, planting of understory species, and implementation of sustainable practices.


Asunto(s)
Carbono/análisis , Bosques , Islas , Análisis Espacio-Temporal , China , Incertidumbre
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