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1.
BMC Pulm Med ; 24(1): 88, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360672

RESUMO

BACKGROUND: Incentive spirometry (IS) as a routine respiratory therapy during the perioperative period has been widely used in clinical practice. However, the impact of IS on patients with perioperative lung cancer remains controversial. This review aimed to evaluate the efficacy of IS in perioperative pulmonary rehabilitation for patients with lung cancer. METHODS: Cochrane Library, PubMed, Web of Science, Ovid, CINAHL, Chinese National Knowledge Infrastructure, Weipu, and Wanfang Databases were searched from inception to 30 November 2023. Only randomized controlled trials were included in this systematic review. The PRISMA checklist served as the guidance for conducting this review. The quality assessment of the included studies was assessed by the Cochrane risk-of-bias tool. The meta-analysis was carried out utilizing Review Manager 5.4. Furthermore, sensitivity analysis and subgroup analysis were also performed. RESULTS: Nine studies recruited 1209 patients met our inclusion criteria. IS combined with other respiratory therapy techniques was observed to reduce the incidence of postoperative pulmonary complications, enhance pulmonary function, curtail the length of hospital stay, and lower the Borg score. Nevertheless, no improvements were found in the six-minute walk distance or quality of life score. CONCLUSIONS: Although IS demonstrates benefits as a component of comprehensive intervention measures for perioperative patients with lung cancer, it proves challenging to determine the precise impact of IS as a standalone component within the comprehensive intervention measures. Therefore, further researches are required to better understand the effectiveness of IS isolation and its interactions when integrated with additional respiratory therapies for these patients. CLINICAL TRIAL REGISTRATION: PROSPERO, https://www.crd.york.ac.uk/prospero/ , registry number: CRD42022321044.


Assuntos
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/cirurgia , Qualidade de Vida , Motivação , Terapia Respiratória/métodos , Complicações Pós-Operatórias/epidemiologia , Espirometria/métodos
2.
Plant Cell Rep ; 43(1): 4, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38117314

RESUMO

KEY MESSAGE: The leaf hyponasty response depends on tip-to-petiole auxin transport. This transport can happen through two parallel pathways: active trans-membrane transport mediated by PIN proteins and passive diffusion through plasmodesmata. A plant's ability to counteract potential shading by neighboring plants depends on transport of the hormone auxin. Neighbor sensing at the leaf tip triggers auxin production. Once this auxin reaches the abaxial petiole epidermis, it causes cell elongation, which leads to leaf hyponasty. Two pathways are known to contribute to this intercellular tip-to-petiole auxin movement: (i) transport facilitated by plasma membrane-localized PIN auxin transporters and (ii) diffusion enabled by plasmodesmata. We tested if these two modes of transport are arranged sequentially or in parallel. Moreover, we investigated if they are functionally linked. Mutants in which one of the two pathways is disrupted indicated that both pathways are necessary for a full hyponasty response. Visualization of PIN3-GFP and PIN7-GFP localization indicated PIN-mediated transport in parallel to plasmodesmata-mediated transport along abaxial midrib epidermis cells. We found plasmodesmata-mediated cell coupling in the pin3pin4pin7 mutant to match wild-type levels, indicating no redundancy between pathways. Similarly, PIN3, PIN4 and PIN7 mRNA levels were unaffected in a mutant with disrupted plasmodesmata pathway. Our results provide mechanistic insight on leaf hyponasty, which might facilitate the manipulation of the shade avoidance response in crops.


Assuntos
Arabidopsis , Arabidopsis/genética , Plasmodesmos , Transporte Biológico , Proteínas de Membrana Transportadoras/genética , Ácidos Indolacéticos
3.
Proc Natl Acad Sci U S A ; 117(11): 6223-6230, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32123097

RESUMO

All multicellular organisms keep a balance between sink and source activities by controlling nutrient transport at strategic positions. In most plants, photosynthetically produced sucrose is the predominant carbon and energy source, whose transport from leaves to carbon sink organs depends on sucrose transporters. In the model plant Arabidopsis thaliana, transport of sucrose into the phloem vascular tissue by SUCROSE TRANSPORTER 2 (SUC2) sets the rate of carbon export from source leaves, just like the SUC2 homologs of most crop plants. Despite their importance, little is known about the proteins that regulate these sucrose transporters. Here, identification and characterization of SUC2-interaction partners revealed that SUC2 activity is regulated via its protein turnover rate and phosphorylation state. UBIQUITIN-CONJUGATING ENZYME 34 (UBC34) was found to trigger turnover of SUC2 in a light-dependent manner. The E2 enzyme UBC34 could ubiquitinate SUC2 in vitro, a function generally associated with E3 ubiquitin ligases. ubc34 mutants showed increased phloem loading, as well as increased biomass and yield. In contrast, mutants of another SUC2-interaction partner, WALL-ASSOCIATED KINASE LIKE 8 (WAKL8), showed decreased phloem loading and growth. An in vivo assay based on a fluorescent sucrose analog confirmed that SUC2 phosphorylation by WAKL8 can increase transport activity. Both proteins are required for the up-regulation of phloem loading in response to increased light intensity. The molecular mechanism of SUC2 regulation elucidated here provides promising targets for the biotechnological enhancement of source strength.


Assuntos
Arabidopsis/fisiologia , Sequestro de Carbono , Carbono/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Mutação , Floema/metabolismo , Fosforilação/fisiologia , Plantas Geneticamente Modificadas , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitinação/fisiologia
4.
Sensors (Basel) ; 23(20)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37896476

RESUMO

Concrete is among the most widely used structural materials in buildings and bridges all over the world. During their service life, concrete structures may inevitably display cracks due to long-term fatigue loads, leading to the degradation of structural integrity. Thus, it is very important to detect cracks and their growth in concrete structures using an automated structural health monitoring system. In this paper, experimental research on crack detection and imaging of concrete structures by using sensing skin and electrical resistance tomography (ERT) is presented. Carbon ink is screen-printed on the surface of concrete as a conductive material to form sensing skins. With these sensing skins, when cracks occur on or near the surface, it breaks the continuity of the sensing skins and significantly reduces conductivity in cracking areas. Then, after exciting small currents in sensing skins and measuring related voltage data, an inverse analysis based on total variation (TV) regularization is adopted to reconstruct tomographic images showing conductivity changes in sensing skins, to detect the occurrence and growth of cracks. The effectiveness of conductive sensing skins and our related crack detection method is validated in experimental studies on a concrete beam subjected to fatigue tests.

5.
Cell Mol Life Sci ; 78(17-18): 6251-6264, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34398251

RESUMO

Ischemic stroke is one of the most serious diseases today, and only a minority of patients are provided with effective clinical treatment. Importantly, leukocytes have gradually been discovered to play vital roles in stroke thrombosis, including promoting the activation of thrombin and the adhesion and aggregation of platelets. However, they have not received enough attention in the field of acute ischemic stroke. It is possible that we could not only prevent stroke-related thrombosis by inhibiting leukocyte activation, but also target leukocyte components to dissolve thrombi in the cerebral artery. In this review, we expound the mechanisms by which leukocytes are activated and participate in the formation of stroke thrombus, then describe the histopathology of leukocytes in thrombi of stroke patients and the influence of leukocyte composition on vascular recanalization effects and patient prognosis. Finally, we discuss the relevant antithrombotic strategies targeting leukocytes.


Assuntos
AVC Isquêmico/patologia , Leucócitos/metabolismo , Trombose/patologia , Armadilhas Extracelulares/efeitos dos fármacos , Armadilhas Extracelulares/metabolismo , Fibrina/metabolismo , Humanos , Sistema Imunitário/metabolismo , AVC Isquêmico/complicações , Ativação Plaquetária , Prognóstico , Trombose/tratamento farmacológico , Trombose/etiologia , Ativador de Plasminogênio Tecidual/farmacologia , Ativador de Plasminogênio Tecidual/uso terapêutico
6.
Int J Mol Sci ; 23(10)2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35628380

RESUMO

C2H2 zinc finger protein (C2H2-ZFP) is one of the most important transcription factor families in higher plants. In this study, a total of 145 C2H2-ZFPs was identified in Sorghum bicolor and randomly distributed on 10 chromosomes. Based on the phylogenetic tree, these zinc finger gene family members were divided into 11 clades, and the gene structure and motif composition of SbC2H2-ZFPs in the same clade were similar. SbC2H2-ZFP members located in the same clade contained similar intron/exon and motif patterns. Thirty-three tandem duplicated SbC2H2-ZFPs and 24 pairs of segmental duplicated genes were identified. Moreover, synteny analysis showed that sorghum had more collinear regions with monocotyledonous plants such as maize and rice than did dicotyledons such as soybean and Arabidopsis. Furthermore, we used quantitative RT-PCR (qRT-PCR) to analyze the expression of C2H2-ZFPs in different organs and demonstrated that the genes responded to cold and drought. For example, Sobic.008G088842 might be activated by cold but is inhibited in drought in the stems and leaves. This work not only revealed an important expanded C2H2-ZFP gene family in Sorghum bicolor but also provides a research basis for determining the role of C2H2-ZFPs in sorghum development and abiotic stress resistance.


Assuntos
Arabidopsis , Dedos de Zinco CYS2-HIS2 , Sorghum , Arabidopsis/genética , Dedos de Zinco CYS2-HIS2/genética , Secas , Grão Comestível , Filogenia , Sorghum/genética , Dedos de Zinco/genética
7.
J Exp Bot ; 72(4): 1073-1084, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33180933

RESUMO

The primary cell walls of plants provide mechanical strength while maintaining the flexibility needed for cell extension growth. Cell extension involves loosening the bonds between cellulose microfibrils, hemicelluloses and pectins. Pectins have been implicated in this process, but it remains unclear if this depends on the abundance of certain pectins, their modifications, and/or structure. Here, cell wall-related mutants of the model plant Arabidopsis were characterized by biochemical and immunohistochemical methods and Fourier-transform infrared microspectroscopy. Mutants with reduced pectin or hemicellulose content showed no root cell elongation in response to simulated drought stress, in contrast to wild-type plants or mutants with reduced cellulose content. While no association was found between the degrees of pectin methylesterification and cell elongation, cell wall composition analysis suggested an important role of the pectin rhamnogalacturonan II (RGII), which was corroborated in experiments with the RGII-modifying chemical 2ß-deoxy-Kdo. The results were complemented by expression analysis of cell wall synthesis genes and microscopic analysis of cell wall porosity. It is concluded that a certain amount of pectin is necessary for stress-induced root cell elongation, and hypotheses regarding the mechanistic basis of this result are formulated.


Assuntos
Arabidopsis , Parede Celular/química , Pectinas/química , Raízes de Plantas/crescimento & desenvolvimento , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Celulose , Raízes de Plantas/citologia
8.
Int J Mol Sci ; 22(24)2021 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-34948385

RESUMO

In plants, seedling growth is subtly controlled by multiple environmental factors and endogenous phytohormones. The cross-talk between sugars and brassinosteroid (BR) signaling is known to regulate plant growth; however, the molecular mechanisms that coordinate hormone-dependent growth responses with exogenous sucrose in plants are incompletely understood. Skotomorphogenesis is a plant growth stage with rapid elongation of the hypocotyls. In the present study, we found that low-concentration sugars could improve skotomorphogenesis in a manner dependent on BR biosynthesis and TOR activation. However, accumulation of BZR1 in bzr1-1D mutant plants partially rescued the defects of skotomorphogenesis induced by the TOR inhibitor AZD, and these etiolated seedlings displayed a normal phenotype like that of wild-type seedlings in response to both sucrose and non-sucrose treatments, thereby indicating that accumulated BZR1 sustained, at least partially, the sucrose-promoted growth of etiolated seedlings (skotomorphogenesis). Moreover, genetic evidence based on a phenotypic analysis of bin2-3bil1bil2 triple-mutant and gain-of-function bin2-1 mutant plant indicated that BIN2 inactivation was conducive to skotomorphogenesis in the dark. Subsequent biochemical and molecular analyses enabled us to confirm that sucrose reduced BIN2 levels via the TOR-S6K2 pathway in etiolated seedlings. Combined with a determination of the cellulose content, our results indicated that sucrose-induced BIN2 degradation led to the accumulation of BZR1 and the enhancement of cellulose synthesis, thereby promoting skotomorphogenesis, and that BIN2 is the converging node that integrates sugar and BR signaling.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Brassinosteroides/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas Quinases/metabolismo , Açúcares/metabolismo , Arabidopsis/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteólise , Transdução de Sinais
9.
Molecules ; 26(18)2021 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-34576992

RESUMO

The extracellular polysaccharide (EPS) matrix embedding microbial cells and soil particles plays an important role in the development of biological soil crusts (BSCs), which is widely recognized as beneficial to soil fertility in dryland worldwide. This study examined the EPS-producing bacterial strains YL24-1 and YL24-3 isolated from sandy soil in the Mu Us Desert in Yulin, Shaanxi province, China. The strains YL24-1 and YL24-3 were able to efficiently produce EPS; the levels of EPS were determined to be 257.22 µg/mL and 83.41 µg/mL in cultures grown for 72 h and were identified as Sinorhizobium meliloti and Pedobacter sp., respectively. When the strain YL24-3 was compared to Pedobacter yulinensis YL28-9T using 16S rRNA gene sequencing, the resemblance was 98.6% and the strain was classified as Pedobacter sp. using physiological and biochemical analysis. Furthermore, strain YL24-3 was also identified as a subspecies of Pedobacter yulinensis YL28-9T on the basis of DNA-DNA hybridization and polar lipid analysis compared with YL28-9T. On the basis of the EPS-related genes of relevant strains in the GenBank, several EPS-related genes were cloned and sequenced in the strain YL24-1, including those potentially involved in EPS synthesis, assembly, transport, and secretion. Given the differences of the strains in EPS production, it is possible that the differences in gene sequences result in variations in the enzyme/protein activities for EPS biosynthesis, assembly, transport, and secretion. The results provide preliminary evidence of various contributions of bacterial strains to the formation of EPS matrix in the Mu Us Desert.


Assuntos
Matriz Extracelular de Substâncias Poliméricas/química , Pedobacter/isolamento & purificação , Pedobacter/fisiologia , Sinorhizobium meliloti/isolamento & purificação , Sinorhizobium meliloti/fisiologia , Técnicas de Tipagem Bacteriana , China , DNA Bacteriano/genética , Clima Desértico , Matriz Extracelular de Substâncias Poliméricas/genética , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Espaço Extracelular/química , Ácidos Graxos/análise , Metais Pesados/farmacologia , Hibridização de Ácido Nucleico , Pedobacter/citologia , Pedobacter/efeitos dos fármacos , Filogenia , RNA Ribossômico 16S/genética , Sinorhizobium meliloti/citologia , Sinorhizobium meliloti/efeitos dos fármacos , Microbiologia do Solo
10.
Molecules ; 26(23)2021 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-34885803

RESUMO

Fungal pathogens have evolved combinations of plant cell-wall-degrading enzymes (PCWDEs) to deconstruct host plant cell walls (PCWs). An understanding of this process is hoped to create a basis for improving plant biomass conversion efficiency into sustainable biofuels and bioproducts. Here, an approach integrating enzyme activity assay, biomass pretreatment, field emission scanning electron microscopy (FESEM), and genomic analysis of PCWDEs were applied to examine digestibility or degradability of selected woody and herbaceous biomass by pathogenic fungi. Preferred hydrolysis of apple tree branch, rapeseed straw, or wheat straw were observed by the apple-tree-specific pathogen Valsa mali, the rapeseed pathogen Sclerotinia sclerotiorum, and the wheat pathogen Rhizoctonia cerealis, respectively. Delignification by peracetic acid (PAA) pretreatment increased PCW digestibility, and the increase was generally more profound with non-host than host PCW substrates. Hemicellulase pretreatment slightly reduced or had no effect on hemicellulose content in the PCW substrates tested; however, the pretreatment significantly changed hydrolytic preferences of the selected pathogens, indicating a role of hemicellulose branching in PCW digestibility. Cellulose organization appears to also impact digestibility of host PCWs, as reflected by differences in cellulose microfibril organization in woody and herbaceous PCWs and variation in cellulose-binding domain organization in cellulases of pathogenic fungi, which is known to influence enzyme access to cellulose. Taken together, this study highlighted the importance of chemical structure of both hemicelluloses and cellulose in host PCW digestibility by fungal pathogens.


Assuntos
Celulases/metabolismo , Celulose/metabolismo , Proteínas Fúngicas/metabolismo , Fungos/fisiologia , Doenças das Plantas/microbiologia , Brassica napus/microbiologia , Brassica napus/fisiologia , Parede Celular/metabolismo , Parede Celular/microbiologia , Fungos/enzimologia , Interações Hospedeiro-Patógeno , Hidrólise , Malus/microbiologia , Malus/fisiologia , Polissacarídeos/metabolismo , Triticum/microbiologia , Triticum/fisiologia , Madeira/microbiologia , Madeira/fisiologia
11.
J Cell Biochem ; 121(2): 1374-1387, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31512786

RESUMO

Long noncoding RNAs (lncRNAs) have been shown to play important roles in human cancers, including esophageal squamous cell carcinoma (ESCC). We previously demonstrated that a novel lncRNA, lnc-ABCA12-3, was overexpressed in ESCC tissues. However, the exact function of lnc-ABCA12-3 is unknown. In the current study, we aimed to evaluate the expression of lnc-ABCA12-3 in ESCC and to explore the potential mechanism of lnc-ABCA12-3 in cell migration, invasion, and proliferation. We showed that lnc-ABCA12-3 was upregulated in ESCC tumor tissues and cell lines. The increased expression of lnc-ABCA12-3 was positively associated with advanced tumor-node-metastasis stages and poor prognosis. The knockdown of lnc-ABCA12-3 inhibited the cell migration, invasion, and proliferation abilities of KYSE-510 and Eca-109 cells. We also found that fibronectin 1 (FN1) was upregulated in ESCC tumor tissues. The expression of FN1 messenger RNA was positively correlated with the expression of lnc-ABCA12-3 in ESCC tumor tissues. After lnc-ABCA12-3 knockdown, the expression of FN1 was downregulated. In addition, the overexpression of FN1 restored the abilities of cell migration, invasion and proliferation in Eca-109 cells. Further studies indicated that lnc-ABCA12-3 acted as a competing endogenous RNA for miR-200b-3p to regulate FN1 expression. In conclusion, these results suggest that lnc-ABCA12-3 is a novel oncogene in tumorigenesis and that its high expression is related to a poor prognosis for patients with ESCC. lnc-ABCA12-3 promotes cell migration, invasion, and proliferation via the regulation of FN1 in ESCC. Our data suggest that lnc-ABCA12-3 might serve as a potential prognostic biomarker and therapeutic target for ESCC.


Assuntos
Movimento Celular , Proliferação de Células , Carcinoma de Células Escamosas do Esôfago/patologia , Fibronectinas/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , RNA Longo não Codificante/genética , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Feminino , Fibronectinas/genética , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas
12.
Appl Environ Microbiol ; 86(15)2020 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-32471912

RESUMO

Filamentous fungi are intensively used for producing industrial enzymes, including lignocellulases. Employing insoluble cellulose to induce the production of lignocellulases causes some drawbacks, e.g., a complex fermentation operation, which can be overcome by using soluble inducers such as cellobiose. Here, a triple ß-glucosidase mutant of Neurospora crassa, which prevents rapid turnover of cellobiose and thus allows the disaccharide to induce lignocellulases, was applied to profile the proteome responses to cellobiose and cellulose (Avicel). Our results revealed a shared proteomic response to cellobiose and Avicel, whose elements included lignocellulases and cellulolytic product transporters. While the cellulolytic proteins showed a correlated increase in protein and mRNA levels, only a moderate correlation was observed on a proteomic scale between protein and mRNA levels (R2 = 0.31). Ribosome biogenesis and rRNA processing were significantly overrepresented in the protein set with increased protein but unchanged mRNA abundances in response to Avicel. Ribosome biogenesis, as well as protein processing and protein export, was also enriched in the protein set that showed increased abundance in response to cellobiose. NCU05895, a homolog of yeast CWH43, is potentially involved in transferring a glycosylphosphatidylinositol (GPI) anchor to nascent proteins. This protein showed increased abundance but no significant change in mRNA levels. Disruption of CWH43 resulted in a significant decrease in cellulase activities and secreted protein levels in cultures grown on Avicel, suggesting a positive regulatory role for CWH43 in cellulase production. The findings should have an impact on a systems engineering approach for strain improvement for the production of lignocellulases.IMPORTANCE Lignocellulases are important industrial enzymes for sustainable production of biofuels and bio-products. Insoluble cellulose has been commonly used to induce the production of lignocellulases in filamentous fungi, which causes a difficult fermentation operation and enzyme loss due to adsorption to cellulose. The disadvantages can be overcome by using soluble inducers, such as the disaccharide cellobiose. Quantitative proteome profiling of the model filamentous fungus Neurospora crassa revealed cellobiose-dependent pathways for cellulase production, including protein processing and export. A protein (CWH43) potentially involved in protein processing was found to be a positive regulator of lignocellulase production. The cellobiose-dependent mechanisms provide new opportunities to improve the production of lignocellulases in filamentous fungi.


Assuntos
Celobiose/metabolismo , Proteínas Fúngicas/metabolismo , Neurospora crassa/metabolismo , Proteoma/metabolismo , beta-Glucosidase/genética , Biocombustíveis/microbiologia , Celulose/metabolismo , Proteínas Fúngicas/genética , Neurospora crassa/enzimologia , Neurospora crassa/genética , Proteoma/genética , beta-Glucosidase/deficiência
13.
J Exp Bot ; 71(19): 5852-5864, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-32640016

RESUMO

Hydrogen sulfide (H2S) is known to have positive physiological functions in plant growth, but limited data are available on its influence on cell walls. Here, we demonstrate a novel mechanism by which H2S regulates the biosynthesis and deposition of cell wall cellulose in alfalfa (Medicago sativa). Treatment with NaHS was found to increase the length of epidermal cells in the hypocotyl, and transcriptome analysis indicated that it caused the differential expression of numerous of cell wall-related genes. These differentially expressed genes were directly associated with the biosynthesis of cellulose and hemicellulose, and with the degradation of pectin. Analysis of cell wall composition showed that NaHS treatment increased the contents of cellulose and hemicellulose, but decreased the pectin content. Atomic force microscopy revealed that treatment with NaHS decreased the diameter of cellulose fibrils, altered the arrangement of the fibrillar bundles, and increased the spacing between the bundles. The dynamics of cellulose synthase complexes (CSCs) were closely related to cellulose synthesis, and NaHS increased the rate of mobility of the particles. Overall, our results suggest that the H2S signal enhances the plasticity of the cell wall by regulating the deposition of cellulose fibrils and by decreasing the pectin content. The resulting increases in cellulose and hemicellulose contents lead to cell wall expansion and cell elongation.


Assuntos
Sulfeto de Hidrogênio , Medicago sativa , Parede Celular , Celulose , Hipocótilo , Medicago sativa/genética
14.
Plant Physiol ; 176(1): 930-945, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29158330

RESUMO

Suc transporters (SUTs) play a key role in the allocation and partitioning of photosynthetically fixed carbon in plants. While a function could be assigned to many members of the SUT family, almost no information is available on their regulation. Here, the transcriptional regulation of SUTs in response to various environmental stimuli in the leaves of five dicots (Arabidopsis [Arabidopsis thaliana], soybean [Glycine max], potato [Solanum tuberosum], tomato [Solanumlycopersicum], and poplar [Populus spp.]) and four monocots (maize [Zeamays], rice [Oryza sativa], wheat [Triticum aestivum], and barley [Hordeum vulgare]) was investigated. Extensive data on expression of SUTs in relation to changes of environmental conditions were obtained through a global analysis of 168 transcriptomics data sets. Results were validated by quantitative PCR measurements and extended by the measurement of photosynthesis rate and phloem sugar content to draw insight on the correlation of SUT expression and sugar export from leaves. For the apoplasmic phloem loaders, a clear difference in transcriptional regulation in response to different environmental stimuli was observed. The consistent patterns of SUT expression under abiotic stress indicates which types of SUTs are involved in the regulation of leaf sugar status and in stress signaling. Furthermore, it is shown that down-regulation of phloem loading is likely to be caused by transcriptional regulation of SUTs, while up-regulation depends on post-transcriptional regulation. In poplar, expression of PtaSUT4 was found to consistently respond to environmental stimuli, suggesting a significant role in the regulation of sugar export from leaves in this passive symplasmic phloem loader.


Assuntos
Sinais (Psicologia) , Meio Ambiente , Proteínas de Membrana Transportadoras/metabolismo , Floema/metabolismo , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Sacarose/metabolismo , Dióxido de Carbono/metabolismo , Secas , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Temperatura Alta , Luz , Floema/efeitos da radiação , Fotossíntese/genética , Fotossíntese/efeitos da radiação , Filogenia , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Plantas/genética , Plantas/efeitos da radiação , Estresse Fisiológico/efeitos da radiação , Transcriptoma/genética
15.
Int J Syst Evol Microbiol ; 68(8): 2523-2529, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29927365

RESUMO

A Gram-staining-negative, rod-shaped, strictly aerobic, non-motile, non-spore-forming, orange bacterium, which was designated strain YL28-9T, was isolated from sandy soil in the district of Yulin, Shaanxi province, PR China, and was characterized by using a polyphasic taxonomic approach. The optimal growth conditions of the strain were 30 °C, pH 7.0, 0 % (w/v) NaCl. Phylogenetic analysis, based on the 16S rRNA gene sequence, revealed that YL28-9T represented a member of the genus Pedobacter and showed the highest sequence similarity to Pedobacter rhizosphaeraeKACC 14938T (95.1 %). The genomic DNA G+C content of this strain was 50.4 mol%, which was out of the range reported for the other strains of members of the genus Pedobacter. The only respiratory quinone detected in YL28-9T was menaquinone-7 (MK-7). The predominant cellular fatty acids were identified as iso-C15 : 0, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and iso-C17 : 0 3-OH. The major polar lipid was phosphatidylethanolamine. On the basis of the results of phenotypic, genotypic, chemotaxonomic and phylogenetic analysis, YL28-9T could be distinguished from the most closely related species of the genus Pedobacter. It is evident from the derived data that YL28-9T represents a novel species of the genus Pedobacter,for which the name Pedobacter yulinensis sp. nov. is proposed. The type strain is YL28-9T (=CGMCC 1.16050T=KCTC 62104T). An emended description of the genus Pedobacteris proposed.


Assuntos
Pedobacter/classificação , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Pedobacter/genética , Pedobacter/isolamento & purificação , Fosfatidiletanolaminas/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
16.
Appl Microbiol Biotechnol ; 102(22): 9577-9584, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30225531

RESUMO

Neurospora crassa is a filamentous fungus potent in secreting cellulase and degrading lignocellulosic materials. Here, heterologous cis-aconitic acid decarboxylase was expressed in N. crassa to synthesize itaconic acid which is a high potential platform chemical with applications as an alternative for petroleum-based products. The present study demonstrated that itaconic acid can be produced directly from cellulose and other lignocellulosic materials by the engineered strain, with the highest production of 20.414 ± 0.674 mg/L. The multivariate data analysis methods were used in the parameter analysis of the conversion process. It was found by the hot map analysis that itaconic acid production can promote the secretion of cellulase in N. crassa. Principal component analysis suggested that itaconic acid production was closely related to the concentration of the glucose degraded from lignocelluloses, indicating that the secretion of cellulase is key to the direct conversion of cellulose to itaconic acid in the engineered N. crassa. This work demonstrates that N. crassa could be considered as a new platform in the application of cellulose conversion to itaconic acid.


Assuntos
Lignina/metabolismo , Neurospora crassa/genética , Neurospora crassa/metabolismo , Succinatos/metabolismo , Biomassa , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Neurospora crassa/crescimento & desenvolvimento
17.
BMC Nurs ; 17: 26, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29977154

RESUMO

BACKGROUND: Research into evidence-based practice has been extensively explored in nursing and there is strong recognition that the organizational context influences implementation. A range of barriers has been identified; however, the research has predominantly taken place in Western cultures, and there is little information about factors that influence evidence-based practice in China. The purpose of this study was to explore barriers and facilitators to evidence-based practice in Hunan province, a less developed region in China. METHODS: A descriptive qualitative methodology was employed. Semi-structured interviews were conducted with staff nurses, head nurses and directors (n = 13). Interviews were translated into English and verified for accuracy by two bilingual researchers. Both Chinese and English data were simultaneously analyzed for themes related to factors related to the evidence to be implemented (Innovation), nurses' attitudes and beliefs (Potential Adopters), and the organizational setting (Practice Environment). RESULTS: Barriers included lack of available evidence in Chinese, nurses' lack of understanding of what evidence-based practice means, and fear that patients will be angry about receiving care that is perceived as non-traditional. Nurses believed evidence-based practice was to be used when clinical problems arose, and not as a routine way to practice. Facilitators included leadership support and the pervasiveness of web based social network services such as Baidu () for easy access to information. CONCLUSION: While several parallels to previous research were found, our study adds to the knowledge base about factors related to evidence-based practice in different contextual settings. Findings are important for international comparisons to develop strategies for nurses to provide evidence-based care.

18.
New Phytol ; 214(1): 245-256, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27935048

RESUMO

In the sieve elements (SEs) of the phloem, carbohydrates are transported throughout the whole plant from their site of production to sites of consumption or storage. SE structure, especially of the pore-rich end walls, has a direct effect on translocation efficiency. Differences in pore size and other features were interpreted as an evolutionary trend towards reduced hydraulic resistance. However, this has never been confirmed. Anatomical data of 447 species of woody angiosperms and gymnosperms were used for a phylogenetic analysis of end wall types, calculation of hydraulic resistance and correlation analysis with morphological and physiological variables. end wall types were defined according to pore arrangement: either grouped into a single area (simple) or into multiple areas along the end wall (compound). Convergent evolution of end wall types was demonstrated in woody angiosperms. In addition, an optimization of end wall resistance with plant height was discovered, but found to be independent of end wall type. While physiological factors also showed no correlation with end wall types, the number of sieve areas per end wall was found to scale with SE length. The results exclude the minimization of hydraulic resistance as evolutionary driver of different end wall types, contradicting this long-standing assumption. Instead, end wall type might depend on SE length.


Assuntos
Evolução Biológica , Floema/anatomia & histologia , Madeira/anatomia & histologia , Clima , Modelos Lineares , Filogenia , Casca de Planta/anatomia & histologia , Caules de Planta/anatomia & histologia , Água
19.
Plant Physiol ; 171(1): 242-50, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26969722

RESUMO

Here we report that phosphorylation status of S211 and T212 of the CESA3 component of Arabidopsis (Arabidopsis thaliana) cellulose synthase impacts the regulation of anisotropic cell expansion as well as cellulose synthesis and deposition and microtubule-dependent bidirectional mobility of CESA complexes. Mutation of S211 to Ala caused a significant decrease in the length of etiolated hypocotyls and primary roots, while root hairs were not significantly affected. By contrast, the S211E mutation stunted the growth of root hairs, but primary roots were not significantly affected. Similarly, T212E caused a decrease in the length of root hairs but not root length. However, T212E stunted the growth of etiolated hypocotyls. Live-cell imaging of fluorescently labeled CESA showed that the rate of movement of CESA particles was directionally asymmetric in etiolated hypocotyls of S211A and T212E mutants, while similar bidirectional velocities were observed with the wild-type control and S211E and T212A mutant lines. Analysis of cell wall composition and the innermost layer of cell wall suggests a role for phosphorylation of CESA3 S211 and T212 in cellulose aggregation into fibrillar bundles. These results suggest that microtubule-guided bidirectional mobility of CESA complexes is fine-tuned by phosphorylation of CESA3 S211 and T212, which may, in turn, modulate cellulose synthesis and organization, resulting in or contributing to the observed defects of anisotropic cell expansion.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Arabidopsis/genética , Glucosiltransferases/metabolismo , Fosforilação , Anisotropia , Arabidopsis/citologia , Proteínas de Arabidopsis/genética , Parede Celular/metabolismo , Celulose/metabolismo , DNA Complementar , Dinitrobenzenos , Estiolamento , Glucosiltransferases/genética , Hipocótilo/metabolismo , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Microtúbulos/metabolismo , Monossacarídeos/análise , Mutagênese Sítio-Dirigida , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Plântula/crescimento & desenvolvimento , Sulfanilamidas
20.
J Pediatr Nurs ; 34: 78-83, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28024900

RESUMO

PROBLEM: Synthesized evidence on the effectiveness of pain management for nasogastric tube (NGT) and orogastric tube (OGT) insertions in infants is lacking. This paper is a systematic review of the effectiveness of pain management for gastric tube (GT) insertion in infants. ELIGIBILITY CRITERIA: Randomized control trial (RCT) or quasi-experimental studies published up to April 2016, on pain management strategies during GT insertions (either NGT or OGT) in infants up to 12months of age. Databases searched included seven English databases and three Chinese databases. RESULTS: Six English studies out of 1236 screened met the eligibility criteria and were included in the review. Two studied OGT insertion and four studies focused on NGT insertion. All six studies evaluated oral sweet solutions (24%-30% sucrose and 25% glucose) compared to placebo (water) or no treatment and all focused on newborn infants. Data from four studies which used the Premature Infant Pain Profile (PIPP) were pooled for meta-analysis. Results showed a significant reduction in PIPP scores during or immediately after the procedure for sweet solution interventions (MD=-2.18, 95% CI (-3.86, -0.51), P=0.01), compared to no intervention or placebo. CONCLUSIONS: Small volumes of oral sweet solutions reduce pain during GT insertion procedure in newborn infants. IMPLICATIONS: Oral sweet solutions can be recommended before GT insertion for newborns in clinical practice. Further studies determining the effect of sweet solution beyond the newborn period, different concentrations of sweet solution and comparison with other pain management strategies are warranted. Systematic review registration number: CRD42016038535. http://www.crd.york.ac.uk/prospero/.


Assuntos
Nutrição Enteral/efeitos adversos , Manejo da Dor/métodos , Dor/etiologia , Edulcorantes/administração & dosagem , Administração Oral , Nutrição Enteral/métodos , Feminino , Glucose/administração & dosagem , Humanos , Lactente , Masculino , Dor/fisiopatologia , Medição da Dor , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Sacarose/administração & dosagem
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