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1.
Int J Mol Sci ; 25(13)2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-39000588

RESUMEN

Sand pear is the main cultivated pear species in China, and brown peel is a unique feature of sand pear. The formation of brown peel is related to the activity of the cork layer, of which lignin is an important component. The formation of brown peel is intimately associated with the biosynthesis and accumulation of lignin; however, the regulatory mechanism of lignin biosynthesis in pear peel remains unclear. In this study, we used a newly bred sand pear cultivar 'Xinyu' as the material to investigate the biosynthesis and accumulation of lignin at nine developmental stages using metabolomic and transcriptomic methods. Our results showed that the 30 days after flowering (DAF) to 50DAF were the key periods of lignin accumulation according to data analysis from the assays of lignin measurement, scanning electron microscope (SEM) observation, metabolomics, and transcriptomics. Through weighted gene co-expression network analysis (WGCNA), positively correlated modules with lignin were identified. A total of nine difference lignin components were identified and 148 differentially expressed genes (DEGs), including 10 structural genes (PAL1, C4H, two 4CL genes, HCT, CSE, two COMT genes, and two CCR genes) and MYB, NAC, ERF, and TCP transcription factor genes were involved in lignin metabolism. An analysis of RT-qPCR confirmed that these DEGs were involved in the biosynthesis and regulation of lignin. These findings further help us understand the mechanisms of lignin biosynthesis and provide a theoretical basis for peel color control and quality improvement in pear breeding and cultivation.


Asunto(s)
Frutas , Regulación de la Expresión Génica de las Plantas , Lignina , Metaboloma , Pyrus , Transcriptoma , Lignina/biosíntesis , Lignina/metabolismo , Pyrus/genética , Pyrus/metabolismo , Pyrus/crecimiento & desarrollo , Frutas/metabolismo , Frutas/genética , Frutas/crecimiento & desarrollo , Redes y Vías Metabólicas , Perfilación de la Expresión Génica/métodos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
Zhonghua Zhong Liu Za Zhi ; 38(1): 4-10, 2016 Jan.
Artículo en Zh | MEDLINE | ID: mdl-26796799

RESUMEN

OBJECTIVE: To investigate the changes of ID1 expression in tumor cells treated with etoposide, cisplatin and ultraviolet (UV) irradiation, and explore the effect of ID1 on chemotherapeutic drug- and UV-induced apoptosis. METHODS: In the present study, upon onset of apoptosis induced by various kinds of inducers such as etoposide, cisplatin and UV irradiation, the expression level of ID1 was detected by Western blot and real-time PCR. We also analyzed the half-life of ID1 protein and stability of ID1 mRNA respectively by cycloheximide inhibition test and RT-PCR. Annexin-V assay was carried out to evaluate the contribution of ID1 protein to chemotherapeutic drug- and UV-induced apoptosis. RESULTS: ID1 expression presented a profound down-regulation in the HCT116 cells treated with etoposide, cisplatin and UV irradiation(P<0.05 for all). The apoptosis in the UV irradiation group, cisplatin group, etoposide group was (58.70±1.55)%, (35.80±0.92)% and (21.00±0.72)%, respectively, significantly higher than that of the control group(1.10±0.07)%, (1.20±0.13)% and (3.50±0.23)% (P<0.05 for all). Upon etoposide treatment, ID1 expression level was decreased via induction of mRNA instability, but not the protein degradation changes. Additionally, ectopic expression of ID1 in the HCT116 cells alleviated etoposide-, cisplatin- and UV-induced apoptosis. The results of flow eytometry revealed that the percentage of apoptotic cells in the ID1 group under the treatment of etoposide, cisplatin and UV irradiation was (23.80±0.82)%, (17.80±1.34)% and (13.40±0.53)%, respectively, significantly lower than that in the empty vector group (41.10±1.61)%, (30.40±2.67)% and (22.50±3.47)% (P<0.05 for all). CONCLUSIONS: These observations indicate that the treatment with etoposide reduces the amount of ID1 by induction of mRNA instability, and exogenously introduced ID1 protects cells against etoposide-, cisplatin- and UV irradiation-induced apoptosis. Inhibition of the ID1 bioactivity may become a new strategy in cancer treatment.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis , Células HCT116 , Proteína 1 Inhibidora de la Diferenciación/metabolismo , Rayos Ultravioleta , Cisplatino/farmacología , Regulación hacia Abajo , Etopósido/farmacología , Células HCT116/efectos de los fármacos , Células HCT116/metabolismo , Células HCT116/efectos de la radiación , Semivida , Humanos , Proteína 1 Inhibidora de la Diferenciación/genética , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa
3.
J Environ Biol ; 36(1): 331-6, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26536812

RESUMEN

Two-year-old pine seedlings, Pinus tabulaeformis and Pinus sylvestris were planted under the canopies of three shrub species and in open areas to test for facilitation during seedling establishment in southeast of Mu Us Sandland in northern part of Shaanxi, China. Pine seedlings establishment were assessed three times within three consecutive growing seasons. Height, area and volume of shrubs were measured. Microclimate conditions (light intensity, air temperature and soil temperature and moisture) were recorded in four microhabitats. Near surface light intensity, air temperature and soil temperature were lower under shrubs, which led to higher soil moisture and pine seedlings under the canopy of shrub species. Pine seedlings survival was remarkably higher when planted under the canopy of shrub species (65.7% for P. tabulaeformis and 60.6% for P. sylvestris) as compared with open areas (22.4% for P. tabulaeformis and 38% for P. sylvestris). P. tabulaeformis with shade-tolerance trait expressed high survival of seedlings as compared to that of P. sylvestris seedlings under the canopy of shrub species (Tukey test, P < 0.05). Leguminous shrub (Caragana korshinskii and Amorpha fruticosa) showed continuously facilitation during moderate drought stress (summer 2012, 2013 and 2014), but dense and small shrub (Caragana korshinskii) reduced the establishment of seedlings possibly for light competition. Salix cheilophila showed a facilitation effect in growing seasons, but the effect of allelopathy led to high mortality of seedlings under their canopy. in addition, two pine growths were not inhibited when planted under three shrubs. In conclusions, nurse-shrub facilitation can be used as an effective restoration strategy in this sandland. However, use of shrubs as nurse plants depends on their canopy structure and ecological impacts; the selection of target species depends on their shade tolerance traits.


Asunto(s)
Ecosistema , Restauración y Remediación Ambiental/métodos , Tracheophyta/crecimiento & desarrollo , China , Luz , Tracheophyta/fisiología
4.
Front Plant Sci ; 15: 1374925, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38606078

RESUMEN

Bud sport is a common and stable somatic variation in perennial fruit trees, and often leads to significant modification of fruit traits and affects the breeding value. To investigate the impact of bud sport on the main metabolites in the fruit of white-fleshed loquat, we conducted a multi-omics analysis of loquat fruits at different developmental stages of a white-fleshed bud sport mutant of Dongting loquat (TBW) and its wild type (TBY). The findings from the detection of main fruit quality indices and metabolites suggested that bud sport resulted in a reduction in the accumulation of carotenoids, fructose, titratable acid and terpenoids at the mature stage of TBW, while leading to the accumulation of flavonoids, phenolic acids, amino acids and lipids. The comparably low content of titratable acid further enhances the balanced and pleasent taste profile of TBW. Expression patterns of differentially expressed genes involved in fructose metabolism exhibited a significant increase in the expression level of S6PDH (EVM0006243, EVM0044405) prior to fruit maturation. The comparison of protein sequences and promoter region of S6PDH between TBY and TBW revealed no structural variations that would impact gene function or expression, indicating that transcription factors may be responsible for the rapid up-regulation of S6PDH before maturation. Furthermore, correlation analysis helped to construct a comprehensive regulatory network of fructose metabolism in loquat, including 23 transcription factors, six structural genes, and nine saccharides. Based on the regulatory network and existing studies, it could be inferred that transcription factors such as ERF, NAC, MYB, GRAS, and bZIP may promote fructose accumulation in loquat flesh by positively regulating S6PDH. These findings improve our understanding of the nutritional value and breeding potential of white-fleshed loquat bud sport mutant, as well as serve as a foundation for exploring the genes and transcription factors that regulate fructose metabolism in loquat.

5.
Hortic Res ; 11(4): uhae103, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38689698

RESUMEN

Prunus zhengheensis, an extremely rare population of apricots, originated in warm South-East China and is an excellent material for genetic breeding. However, most apricots and two related species (P. sibirica, P. mandshurica) are found in the cold northern regions in China and the mechanism of their distribution is still unclear. In addition, the classification status of P. zhengheensis is controversial. Thus, we generated a high-quality haplotype-resolved genome for P. zhengheensis, exploring key genetic variations in its adaptation and the causes of phylogenetic incongruence. We found extensive phylogenetic discordances between the nuclear and organelle phylogenies of P. zhengheensis, which could be explained by incomplete lineage sorting. A 242.22-Mb pan-genome of the Armeniaca section was developed with 13 chromosomal genomes. Importantly, we identified a 566-bp insertion in the promoter of the HSFA1d gene in apricot and showed that the activity of the HSFA1d promoter increased under low temperatures. In addition, HSFA1d overexpression in Arabidopsis thaliana indicated that HSFA1d positively regulated plant growth under chilling. Therefore, we hypothesized that the insertion in the promoter of HSFA1d in apricot improved its low-temperature adaptation, allowing it to thrive in relatively cold locations. The findings help explain the weather adaptability of Armeniaca plants.

6.
Genes (Basel) ; 14(9)2023 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-37761819

RESUMEN

SWEETs (sugars will eventually be exported transporters) play a vital role in longer-distance sugar transportation, and thus control carbon flow and energy metabolism in plants. SWEET genes have been identified in various plant species, but their functions in fruit development remain uncharacterized. Here, we isolated 15 putative PsSWEETs from the Prunus salicina genome. For further analysis, comprehensive bioinformatics methods were applied to determine the gene structure, chromosome distribution, phylogeny, cis-acting regulatory elements, and expression profiles of PsSWEETs. qRT-PCR analysis suggested that these SWEETs might have diverse functions in the development of plum fruit. The relative expression levels of PsSWEET1 and PsSWEET9 were obviously higher in ripened fruit than the ones in other developmental stages, suggesting their possible roles in the transport and accumulation of sugars in plum fruit. Positive correlations were found between the expression level of PsSWEET3/10/13 and the content of sucrose, and the expression level of PsSWEET2 and the content of fructose, respectively, during the development of 'Furongli' fruit, suggesting their possible roles in the accumulation of sucrose and fructose. The current study investigated the initial genomic characterization and expression patterns of the SWEET gene family in plum, which could provide a foundation for the further understanding of the functional analysis of the SWEET gene family.


Asunto(s)
Prunus domestica , Frutas/genética , Reproducción , Fructosa , Sacarosa
7.
Alzheimers Res Ther ; 15(1): 32, 2023 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-36765411

RESUMEN

BACKGROUND: Electroencephalogram (EEG) has emerged as a non-invasive tool to detect the aberrant neuronal activity related to different stages of Alzheimer's disease (AD). However, the effectiveness of EEG in the precise diagnosis and assessment of AD and its preclinical stage, amnestic mild cognitive impairment (MCI), has yet to be fully elucidated. In this study, we aimed to identify key EEG biomarkers that are effective in distinguishing patients at the early stage of AD and monitoring the progression of AD. METHODS: A total of 890 participants, including 189 patients with MCI, 330 patients with AD, 125 patients with other dementias (frontotemporal dementia, dementia with Lewy bodies, and vascular cognitive impairment), and 246 healthy controls (HC) were enrolled. Biomarkers were extracted from resting-state EEG recordings for a three-level classification of HC, MCI, and AD. The optimal EEG biomarkers were then identified based on the classification performance. Random forest regression was used to train a series of models by combining participants' EEG biomarkers, demographic information (i.e., sex, age), CSF biomarkers, and APOE phenotype for assessing the disease progression and individual's cognitive function. RESULTS: The identified EEG biomarkers achieved over 70% accuracy in the three-level classification of HC, MCI, and AD. Among all six groups, the most prominent effects of AD-linked neurodegeneration on EEG metrics were localized at parieto-occipital regions. In the cross-validation predictive analyses, the optimal EEG features were more effective than the CSF + APOE biomarkers in predicting the age of onset and disease course, whereas the combination of EEG + CSF + APOE measures achieved the best performance for all targets of prediction. CONCLUSIONS: Our study indicates that EEG can be used as a useful screening tool for the diagnosis and disease progression evaluation of MCI and AD.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Enfermedad de Alzheimer/psicología , Disfunción Cognitiva/psicología , Biomarcadores , Electroencefalografía , Progresión de la Enfermedad , Apolipoproteínas E
8.
Artículo en Inglés | MEDLINE | ID: mdl-22653265

RESUMEN

Gp96 (GRP94) is a chaperone that is responsible for molecular folding and assembly of proteins. To investigate correlations among Gp96 expression, sensitivity to radiotherapy and clinical features of nasopharyngeal carcinoma (NPC), the expression of Gp96 in 98 NPC samples was analyzed by immunohistochemistry and Western blotting at the protein level, and by real-time PCR at the mRNA level. Clinicopathological features, including stage, sex, grade and survival, were compared between the high and low Gp96 expression groups. As a result, Gp96 was expressed at a higher level in NPC tissues than in noncancerous nasopharyngeal mucosa (p = 0.001). Univariate analysis suggested that a higher Gp96 expression level was associated with significantly decreased disease-free and 5-year survival rates (p = 0.000, p = 0.000, respectively). Multivariate Cox proportional-hazard regression analysis, which adjusts for clinicopathological variables, indicated that it was only associated with the 5-year overall survival rate (p = 0.002). Furthermore, patients with high Gp96 expression levels were significantly more resistant to radiotherapy (p = 0.001). These data are the first indication of a positive correlation between Gp96 expression levels and radiosensitivity and 5-year survival rate. Gp96 might serve as a novel candidate marker for predicting the long-term prognostic outcome of NPC.


Asunto(s)
Carcinoma de Células Escamosas , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Neoplasias Nasofaríngeas , Tolerancia a Radiación/genética , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/fisiopatología , Carcinoma de Células Escamosas/radioterapia , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Neoplasias Nasofaríngeas/mortalidad , Neoplasias Nasofaríngeas/fisiopatología , Neoplasias Nasofaríngeas/radioterapia , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Factores de Riesgo , Regulación hacia Arriba/genética , Regulación hacia Arriba/efectos de la radiación , Adulto Joven
9.
Acta Neurobiol Exp (Wars) ; 82(2): 237-243, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35833823

RESUMEN

Pituitary adenoma is a typical adult primary brain tumor and 35% of pituitary adenomas are invasive. The enhancement of angiogenesis is essential for the spread and invasiveness of invasive pituitary adenoma. Thus, it is urgent to uncover the mechanism and relevant biomolecular targets for the therapy and prognosis of pituitary adenomas. The HP75 cells were transfected with si­NC, si­TFF3, pcDNA, and pcDNA­TFF3 to investigate the effects of TFF3 on the proliferation, migration and invasion of pituitary tumor cell. The protein level of TFF3 and HIF­1α/VEGFA was determined by western blot. The transwell migration assay and wound healing assay were used to investigate the influence of TFF3 on the cell migration and invasion of HP75 cells. The tumor angiogenesis was determined by tube formation assay. The proliferation of HP75 cells was assessed by using MTT assay and colony­forming unit assay. The cell proliferation rate was separately enhanced and reduced remarkably in TFF3 overexpression group and si­TFF3 group. TFF3 could modulate the proliferation, migration and invasion ability of HP75 cells. Furthermore, TFF3 may play a oncogenic role in HP75 cells. Overexpression of TFF3 enhanced the number of branching points and network formation in HP75 cells, suggesting the TFF3 had positive effects on cell angiogenesis. These results also disclosed a novel relationship between TFF3 expression and the activation of the HIF­1α/VEGFA signaling pathway. In summary, this study uncovered new insight into the mechanisms of TFF3's anti­tumor activities in pituitary adenoma cells by investigating its effects on HIF­1α/VEGFA signaling pathway regulation.


Asunto(s)
Adenoma , Neovascularización Patológica , Neoplasias Hipofisarias , Factor Trefoil-3 , Factor A de Crecimiento Endotelial Vascular , Adenoma/genética , Adenoma/metabolismo , Adenoma/patología , Adulto , Línea Celular Tumoral , Movimiento Celular/genética , Movimiento Celular/fisiología , Proliferación Celular/genética , Proliferación Celular/fisiología , Humanos , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología , Neoplasias Hipofisarias/genética , Neoplasias Hipofisarias/metabolismo , Neoplasias Hipofisarias/patología , Transducción de Señal , Factor Trefoil-3/genética , Factor Trefoil-3/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
10.
Sci Rep ; 12(1): 14378, 2022 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-35999245

RESUMEN

An increasing number of studies have been devoted to electroencephalogram (EEG) identity recognition since EEG signals are not easily stolen. Most of the existing studies on EEG person identification have only addressed brain signals in a single state, depending upon specific and repetitive sensory stimuli. However, in reality, human states are diverse and rapidly changing, which limits their practicality in realistic settings. Among many potential solutions, transformer is widely used and achieves an excellent performance in natural language processing, which demonstrates the outstanding ability of the attention mechanism to model temporal signals. In this paper, we propose a transformer-based approach for the EEG person identification task that extracts features in the temporal and spatial domains using a self-attention mechanism. We conduct an extensive study to evaluate the generalization ability of the proposed method among different states. Our method is compared with the most advanced EEG biometrics techniques and the results show that our method reaches state-of-the-art results. Notably, we do not need to extract any features manually.


Asunto(s)
Interfaces Cerebro-Computador , Electroencefalografía , Encéfalo , Electroencefalografía/métodos , Humanos
11.
Front Neurosci ; 16: 923587, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36408382

RESUMEN

Action recognition is an exciting research avenue for artificial intelligence since it may be a game changer in emerging industrial fields such as robotic visions and automobiles. However, current deep learning (DL) faces major challenges for such applications because of the huge computational cost and inefficient learning. Hence, we developed a novel brain-inspired spiking neural network (SNN) based system titled spiking gating flow (SGF) for online action learning. The developed system consists of multiple SGF units which are assembled in a hierarchical manner. A single SGF unit contains three layers: a feature extraction layer, an event-driven layer, and a histogram-based training layer. To demonstrate the capability of the developed system, we employed a standard dynamic vision sensor (DVS) gesture classification as a benchmark. The results indicated that we can achieve 87.5% of accuracy which is comparable with DL, but at a smaller training/inference data number ratio of 1.5:1. Only a single training epoch is required during the learning process. Meanwhile, to the best of our knowledge, this is the highest accuracy among the non-backpropagation based SNNs. Finally, we conclude the few-shot learning (FSL) paradigm of the developed network: 1) a hierarchical structure-based network design involves prior human knowledge; 2) SNNs for content-based global dynamic feature detection.

12.
Neurol Ther ; 11(2): 835-849, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35428921

RESUMEN

INTRODUCTION: Even though adrenocorticotropic hormone (ACTH) demonstrated powerful efficacy in the initially successful treatment of infantile spasms (IS), nearly one-half of patients whose spasms were once suppressed experienced relapse. There is currently no validated method for the prediction of the risk of relapse. The Burden of Amplitudes and Epileptiform Discharges (BASED) score is an electroencephalogram (EEG) grading scale for children with infantile spasms. We sought to determine whether an association exists between the BASED score after ACTH treatment and relapse after initial response with ACTH. METHODS: Children with IS who achieved initial response after ACTH treatment were selected as the study subjects. Those who experienced relapse within 12 months after ACTH treatment were categorized as the relapse group, and those who did not were categorized as the non-relapse group. Their general clinical data and EEG data (using BASED scoring) after ACTH treatment were collected, and compared between groups. Cox proportional hazards models were fit to determine factors associated with relapse. RESULTS: A total of 64 children with IS were enrolled in the study, of which 37 (57.8%) experienced a relapse, and the median duration after ACTH treatment was 3 (1.5, 6) months. The BASED score was significantly higher in the relapse group than in the non-relapse group. Cox modeling demonstrated that BASED score was independently associated with relapse. The patients with a score greater than or equal to 3 showed a high rate (89.3%) of relapse. The relapse group had stronger, more stable EEG functional networks than the non-relapse group, and there were obvious correlations between BASED score and functional connectivity. CONCLUSION: This study suggests the BASED score after ACTH treatment has potential value as a predictor for relapse after initial response. Children with IS who have a BASED score greater than or equal to 3 after the initial response of ACTH carry a high risk of relapse within 1 year.

13.
RSC Adv ; 11(33): 20326-20334, 2021 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-35479874

RESUMEN

Surface enhanced Raman spectroscopy (SERS) is a promising sensing technique that can provide unique chemical and structural fingerprint information, but gaining reliable SERS quantitative data with high sensitivity and stability still remains a challenge. Although using a molecule as an internal standard (IS) can improve the SERS quantitative capability, the reliability and SERS measuring conditions for signal fluctuations during calibration based on IS are yet to be explored when the embedded IS molecules and target objects are located in different environments. Herein, a 3D hotspot matrix SERS platform based on Au@4-MPy@AgNPs was constructed in water with the assistance of glycerol and the dynamic signal changes from the IS, i.e. 4-Mpy, and target molecules were monitored during the process of evaporation with high sensitivity and stability. In contrast to the traditional water-dispersed drying film system, the variation trends of IS and target molecules were consistent in the glycerol-assisted liquid film protection system. Therefore, it is reasonable to calibrate the signal fluctuation by utilizing the embedded IS based on the construction strategy of a glycerol-assisted 3D hotspot platform. This work demonstrates a rational, reliable and precise SERS quantitative technique for testing analyte concentrations in practical systems and has great application prospects in the field of analytical chemistry.

14.
Ecol Evol ; 9(7): 4087-4102, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31015990

RESUMEN

Plants' pattern of compensatory growth is often used to intuitively estimate their grazing tolerance. However, this tolerance is sometimes measured by the overall grazing tolerance index (overall GTI), which assumes that tolerance is a multivariate linear function of various underlying mechanisms. Because the interaction among mechanisms is not independent, the grazing tolerance expression based on overall GTI may be inconsistent with that based on compensatory growth. Through a manipulative field experiment from 2007 to 2012, we measured the responses of 12 traits of Elymus nutans to clipping under different resource availabilities in an alpine meadow and explored the compensatory aboveground biomass and the overall GTI to assess the possible differences between the two expressions of tolerance. Our results showed that these two expressions of tolerance were completely opposite. The expression based on overall GTI was over-compensatory and did not vary with clipping and resource availability, while the expression based on compensatory aboveground biomass was under-compensatory and altered to over-compensation after fertilization. The over-expression of highly variable traits with extremely high negative mean GTI to defoliation damage, the influence of random errors contained in traits considered, and the doubling weight of functional redundant traits greatly inflated the overall GTI, which leads to the inconsistency of the two tolerance expressions. This inconsistency is also associated with the different determining mechanisms of the two tolerance expressions. Our data suggest that plants' grazing tolerance is not a multivariate linear function of traits or mechanisms that determine grazing tolerance; the overall GTI is only a measure of traits' variability to defoliation damage. Our findings highlight that the tolerance of E. nutans mainly depends on the response of traits with lower variability to defoliation, and the overall GTI is not an ideal predictor for describing a single-species tolerance to grazing.

15.
Mitochondrial DNA B Resour ; 5(1): 296-297, 2019 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-33366527

RESUMEN

A new super Kadsura coccinea, named 'black tiger 2', was selected from variant forms of seedlings. In this study, The complete chloroplast (cp) genome of 'black tiger 2' was obtained. The complete cp genome is 145,608 in length, and contained 126 genes, including 83 protein-coding genes, 8 ribosomal RNA genes, and 35 transfer RNA genes. Phylogenetic analyses established that 'black tiger 2' was closely clustered with other Schisandraceae species such as Schisandra chinensis and Illicium, which helps elucidate the phylogenetic relationship between 'black tiger 2' and other species.

17.
J Integr Plant Biol ; 50(6): 659-72, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18713406

RESUMEN

Grazing by domestic herbivores is generally recognized as a major ecological factor and an important evolutionary force in grasslands. Grazing has both extensive and profound effects on individual plants and communities. We investigated the response patterns of Polygonum viviparum species and the species diversity of an alpine shrub meadow in response to long-term livestock grazing by a field manipulative experiment controlling livestock numbers on the Qinghai-Tibet Plateau in China. Here, we hypothesize that within a range of grazing pressure, grazing can alter relative allocation to different plant parts without changing total biomass for some plant species if there is life history trade-offs between plant traits. The same type of communities exposed to different grazing pressures may only alter relative species' abundances or species composition and not vary species diversity because plant species differ in resistant capability to herbivory. The results show that plant height and biomass of different organs differed among grazing treatments but total biomass remained constant. Biomass allocation and absolute investments to both reproduction and growth decreased and to belowground storage increased with increased grazing pressure, indicating the increasing in storage function was attained at a cost of reducing reproduction of bulbils and represented an optimal allocation and an adaptive response of the species to long-term aboveground damage. Moreover, our results showed multiform response types for either species groups or single species along the gradient of grazing intensity. Heavy grazing caused a 13.2% increase in species richness. There was difference in species composition of about 18%-20% among grazing treatment. Shannon-Wiener (H') diversity index and species evenness (E) index did not differ among grazing treatments. These results support our hypothesis.


Asunto(s)
Animales Domésticos/fisiología , Ecosistema , Conducta Alimentaria/fisiología , Polygonum/fisiología , Animales , Biomasa , Dinámica Poblacional , Carácter Cuantitativo Heredable , Análisis de Regresión , Especificidad de la Especie , Tibet , Factores de Tiempo
18.
J Colloid Interface Sci ; 316(2): 825-30, 2007 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-17900599

RESUMEN

Low molecular mass organic gelator (LMOG) as an important component of liquid crystal physical gel has a great influence on the electro-optical properties. In this paper, three analogues of amide gelator were synthesized and employed as LMOGs in nematic liquid crystal 5CB. Both hydrogen-bonding and pi-pi-stacking interactions in the gel phase were found to stabilize the self-assembled structure. It was observed that the morphology was highly dependent on the crystallinity of gelators, which was affected by the intensity of hydrogen bonding. The thicker fibril was obtained with higher crystallinity of LMOG, while the thinner fibril was obtained with lower crystallinity. Moreover, the electro-optical properties of liquid crystal physical gels were proposed to be related to the interaction between the fibrils and the liquid crystal molecules.


Asunto(s)
Amidas/química , Electrones , Cristales Líquidos/química , Óptica y Fotónica , Fenómenos Químicos , Química Física , Geles/química , Estructura Molecular , Peso Molecular , Tamaño de la Partícula , Espectrofotometría Infrarroja/métodos , Propiedades de Superficie , Difracción de Rayos X
19.
Anal Chim Acta ; 853: 402-414, 2015 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-25467485

RESUMEN

Resolving components and determining their pseudo-molecular ions (PMIs) are crucial steps in identifying complex herbal mixtures by liquid chromatography-mass spectrometry. To tackle such labor-intensive steps, we present here a novel algorithm for simultaneous detection of components and their PMIs. Our method consists of three steps: (1) obtaining a simplified dataset containing only mono-isotopic masses by removal of background noise and isotopic cluster ions based on the isotopic distribution model derived from all the reported natural compounds in dictionary of natural products; (2) stepwise resolving and removing all features of the highest abundant component from current simplified dataset and calculating PMI of each component according to an adduct-ion model, in which all non-fragment ions in a mass spectrum are considered as PMI plus one or several neutral species; (3) visual classification of detected components by principal component analysis (PCA) to exclude possible non-natural compounds (such as pharmaceutical excipients). This algorithm has been successfully applied to a standard mixture and three herbal extract/preparations. It indicated that our algorithm could detect components' features as a whole and report their PMI with an accuracy of more than 98%. Furthermore, components originated from excipients/contaminants could be easily separated from those natural components in the bi-plots of PCA.


Asunto(s)
Algoritmos , Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Estadística como Asunto/métodos , Medicamentos Herbarios Chinos/química , Peso Molecular , Análisis de Componente Principal , Factores de Tiempo
20.
Mol Med Rep ; 9(1): 333-9, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24248266

RESUMEN

Basic fibroblast growth factor (bFGF) has proven useful for neural stem and progenitor cells during the transplantation­mediated therapeutic effect of bone mesenchymal stem cells (BMSCs). Endogenous bFGF expression levels increase during brain development and gradually diminish with aging. To date, few studies have been conducted on exogenous bFGF promoting BMSC transplantation­mediated functional recovery in adult rats following traumatic brain injury (TBI). The results of the present study showed that BMSCs in the TBI cortex and dentate gyrus showed differentiation along the glial and neuronal lines, which are possibly enhanced by bFGF. The neuronal differentiation rate was not consistent with neurological functional recovery rate over time. bFGF may promote the transplantation­mediated therapeutic effect of BMSCs more significantly and rapidly in rats following TBI, with a small proportion of differentiated neurons. In conclusion, exogenous bFGF functions as a booster of the transplantation­mediated therapeutic effect of BMSCs following TBI.


Asunto(s)
Lesiones Encefálicas/cirugía , Factor 2 de Crecimiento de Fibroblastos/farmacología , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/efectos de los fármacos , Animales , Células de la Médula Ósea/citología , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Corteza Cerebral/citología , Giro Dentado/citología , Modelos Animales de Enfermedad , Masculino , Células Madre Mesenquimatosas/citología , Ratas , Ratas Sprague-Dawley , Recuperación de la Función
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