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1.
J Inorg Biochem ; 225: 111622, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34624670

RESUMO

The studies of iridium (III) complexes as potent anticancer reagents have attracted great attention. Here, a new iridium (III) complex [Ir(bzq)2(PYIP)](PF6) (Ir1, bzq = benzo[h]quinoline, PYIP = 2-(pyren-1-yl)-1H-imidazo[4,5-f][1,10]phenanthroline) was synthesized and its liposomes (Ir1Lipo) was prepared. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method was used to detect the cytotoxic activity of Ir1 and Ir1Lipo on HepG2, SGC-7901, BEL-7402, HeLa, B16, A549 and normal NIH3T3 cells. The complex Ir1 displays no obvious inhibitory effect on the growth of BEL-7402 cells, while the Ir1Lipo shows significant cytotoxic activity on BEL-7402 cells (IC50 = 2.6 ± 0.03 µM). In further studies, Ir1Lipo induced apoptosis by the mitochondrial pathways, such as increasing intracellular reactive oxygen species (ROS) content and intracellular Ca2+ level, decreasing the mitochondrial membrane potential (MMP). In addition, after incubation with Ir1Lipo, the colony formation of BEL-7402 cells was significantly inhibited. Moreover, flow cytometry was used to detect the impact of Ir1Lipo on cell cycle distribution, and western blot was used to detect the expression of caspases and Bcl-2 (B-cell lymphoma-2) family proteins. Furthermore, Ir1Lipo exhibited significant antitumor activity in vivo with an inhibitory rate of 65.8%. These results indicated that Ir1Lipo induces apoptosis in BEL-7402 cells through intrinsic mitochondrial pathway.

3.
Tree Physiol ; 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34625806

RESUMO

Populus ussuriensis is an important and fast-growing afforestation plant species in north-eastern China. The whole-genome sequencing of P. ussuriensis has not been completed. Also, the transcriptional network of P. ussuriensis response to cold stress remains unknown. To unravel the early response of P. ussuriensis to chilling (3°C) stress and freezing (-3°C) stresses at the transcriptional level, we performed Single-Molecule Real-Time (SMRT) and Illumina RNA sequencing for P. ussuriensis. SMRT long-read isoform sequencing led to the identification of 29,243,277 subreads, and 575,481 circular consensus sequencing (CCS) reads. Approximately 50,910 high-quality (HQ) isoforms were generated, and 2,272 simple sequence repeats (SSRs), 8,086 long non-coding RNAs (lncRNAs) were identified. The Ca2+ content and abscisic acid (ABA) content in P. ussuriensis were significantly increased under cold stresses, while the value in freezing stress treatment group was significantly higher than chilling stress treatment group. A total of 49 genes that are involved in the signal transduction pathways related to perception and transmission of cold stress signals, such as Ca2+ signaling pathway, ABA signaling pathway, and MAPK signaling cascade, were found to be differentially expressed. In addition, 158 transcription factors (TFs) from 21 different families, such as MYB, WRKY, and AP2/ERF, were differentially expressed during chilling and freezing treatments. Moreover, the measurement of physiological indicators and bioinformatics observations demonstrated the altered expression pattern of genes involved in reactive oxygen species (ROS) balance, and sugar metabolism pathway during chilling and freezing stresses. This is the first time to report the early responses of P. ussuriensis to cold stress, which lays the foundation for future studies on the regulatory mechanisms in cold stress response. Besides, the full-length reference transcriptome of P. ussuriensis deciphered could be used in future studies on P. ussuriensis.

4.
PLoS One ; 16(9): e0256870, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34520454

RESUMO

Although they represent the cornerstone of analgesic therapy, opioids, such as morphine, are limited in efficacy by drug tolerance, hyperalgesia and other side effects. Activation of microglia and the consequent production of proinflammatory cytokines play a key pathogenic role in morphine tolerance, but the exact mechanisms are not well understood. This study aimed to investigate the regulatory mechanism of epidermal growth factor receptor (EGFR) on microglial activation induced by morphine in mouse microglial BV-2 cells. In this research, BV-2 cells were stimulated with morphine or pretreated with AG1478 (an inhibitor of EGFR). Expression levels of cluster of differentiation molecule 11b (CD11b), EGFR, and phospho-EGFR were detected by immunofluorescence staining. Cell signaling was assayed by Western blot. The migration ability of BV-2 cells was tested by Transwell assay. The production of interleukin-1beta (IL-1ß) and tumor necrosis factor-alpha (TNF-α) in the cell supernatant was determined by ELISA. We observed that the expression of CD11b induced by morphine was increased in a dose- and time- dependent manner in BV-2 cells. Phosphorylation levels of EGFR and ERK1/2, migration of BV-2 cells, and production of IL-1ß and TNFα were markedly enhanced by morphine treatment. The activation, migration, and production of proinflammatory cytokines in BV-2 cells were inhibited by blocking the EGFR signaling pathway with AG1478. The present study demonstrated that the EGFR/ERK signaling pathway may represent a novel pharmacological strategy to suppress morphine tolerance through attenuation of microglial activation.

5.
Rapid Commun Mass Spectrom ; : e9200, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34532912

RESUMO

RATIONALE: Succus Bambusae is consumed as a kind of herbal medicine and natural beverage in China. However, the current quality standards of Succus Bambusae are low and lack of safety indicators, which makes it difficult to effectively guarantee its quality. Therefore, it is of great significance to study the identification and quality control technology for the product. METHODS: In this research, A set of qualitative and quantitative methods based on gas chromatography-mass spectrometry (GC-MS) was developed for the analysis of volatile components in Succus Bambusae oral liquid (SBOL). Combining GC-MS fingerprint analysis and related chemometrics algorithms, with similarity evaluation, Hotelling T2 and distance to Model X (DModX) as criteria, the quality consistency of different batches was evaluated, and the SBOL samples from different manufacturers were differentiated. RESULTS: 29 volatile components were preliminarily identified from 40 batches of SBOL samples from 6 manufacturers, and 6 Q-markers (Quality Markers) for the SBOLs was disscussed and determined using GC-MS. The products from different manufacturers were distinguished using Chemometrics. CONCLUSIONS: The results showed that the quality of the SBOL samples of different batches and different manufacturers fluctuated greatly, which suggested that the researches of raw materials and manufacturing techniques should be strengthened to improve the quality of SBOL and ensure its quality consistency.

6.
J Pharm Sci ; 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34563535

RESUMO

The effect of transporters and enzymes on drug pharmacokinetics is increasingly evaluated using genetically modified animals that have these proteins either knocked-out or their human orthologues transgenically expressed. Analysis of pharmacokinetic data obtained in such experiments is typically performed using non-compartmental analysis (NCA), which has limitations such as not being able to identify the PK parameter that is affected by the genetic modification of the enzymes or transporters and the requirement of intense and homogeneous sampling of all subjects. Here we used a compartmental population pharmacokinetic modeling approach using PK data from a series of genetically modified mouse experiments with lorlatinib to extend the results and conclusions from previously reported NCA analyses. A compartmental population pharmacokinetic model was built and physiologically plausible covariates were evaluated for the different mouse strains. With the model, similar effects of the strains on the area under the concentration-time curve (AUC) from 0 to 8 hours were found as for the NCA. Additionally, the differences in AUC between the strains were explained by specific effects on clearance and bioavailability for the strain with human expressing CYP3A4. Finally, effects of multidrug efflux transporters ATP-binding cassette (ABC) sub-family B member 1 (ABCB1) and G member 2 (ABCG2) on brain efflux were quantified. Use of compartmental population PK modeling yielded additional insight into the role of drug-metabolizing enzymes and drug transporters in mouse experiments compared to the NCA. Furthermore, these models allowed analysis of heterogeneous pooled datasets and the sparse organ concentration data in contrast to classical NCA analyses.

7.
Plant Biotechnol J ; 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34487637

RESUMO

Legume-rhizobia symbiosis enables biological nitrogen fixation to improve crop production for sustainable agriculture. Small heat shock proteins (sHSPs) are involved in multiple environmental stresses and plant development processes. However, the role of sHSPs in nodule development in soybean remains largely unknown. In the present study, we identified a nodule-localized sHSP, called GmHSP17.9, in soybean, which was markedly up-regulated during nodule development. GmHSP17.9 was specifically expressed in the infected regions of the nodules. GmHSP17.9 overexpression and RNAi in transgenic composite plants and loss of function in CRISPR-Cas9 gene-editing mutant plants in soybean resulted in remarkable alterations in nodule number, nodule fresh weight, nitrogenase activity, contents of poly ß-hydroxybutyrate bodies (PHBs), ureide and total nitrogen content, which caused significant changes in plant growth and seed yield. GmHSP17.9 was also found to act as a chaperone for its interacting partner, GmNOD100, a sucrose synthase in soybean nodules which was also preferentially expressed in the infected zone of nodules, similar to GmHSP17.9. Functional analysis of GmNOD100 in composite transgenic plants revealed that GmNOD100 played an essential role in soybean nodulation. The hsp17.9 lines showed markedly more reduced sucrose synthase activity, lower contents of UDP-glucose and acetyl coenzyme A (acetyl-CoA), and decreased activity of succinic dehydrogenase (SDH) in the tricarboxylic acid (TCA) cycle in nodules due to the missing interaction with GmNOD100. Our findings reveal an important role and an unprecedented molecular mechanism of sHSPs in nodule development and nitrogen fixation in soybean.

8.
Int J Biol Macromol ; 191: 540-547, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34571121

RESUMO

Biodegradable poly (lactide) (PLA) and poly (butylene adipate-co-terephthalate) (PBAT) composite films were made by a co-precipitation and hot-pressing method. The property of composite films like the chemical interaction, phase morphology, mechanical properties, and thermal properties were studied. The Fourier transform infrared spectroscopy (FTIR) test manifested that there was a small amount of the transesterifications between the PBAT and PLA during hot pressing, which could improve the compatibility of the two phases. The tensile strength of the film only reduced by 7.4%, while the elongation at break was increased by 119.1% compared with PLA after adding 4%wt PBAT. The composite films showed a high Ultraviolet-visible (UV) light barrier property. The UV blocking rate of the composite after adding 4%wt PBAT was 6.95 times higher than that of pure PLA at 380 nm. The PLA/PBAT composite films with excellent thermal stability, satisfactory mechanical properties and UV-light barrier have high a possibility for an UV screening packaging application.

9.
Adv Sci (Weinh) ; 8(19): e2100368, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34351704

RESUMO

Healthcare-acquired infections as well as increasing antimicrobial resistance have become an urgent global challenge, thus smart alternative solutions are needed to tackle bacterial infections. Antibacterial materials in biomedical applications and hospital hygiene have attracted great interest, in particular, the emergence of surface design strategies offer an effective alternative to antibiotics, thereby preventing the possible development of bacterial resistance. In this review, recent progress on advanced surface modifications to prevent bacterial infections are addressed comprehensively, starting with the key factors against bacterial adhesion, followed by varying strategies that can inhibit biofilm formation effectively. Furthermore, "super antibacterial systems" through pre-treatment defense and targeted bactericidal system, are proposed with increasing evidence of clinical potential. Finally, the advantages and future challenges of surface strategies to resist healthcare-associated infections are discussed, with promising prospects of developing novel antimicrobial materials.

10.
J Inorg Biochem ; 224: 111580, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34438219

RESUMO

In this report, we synthesized three new iridium(III) complexes: [Ir(piq)2(apip)]PF6 (Ir1, piq = 1-phenylisoquinoline, apip = 2-aminophenyl-1H-imidazo[4,5-f][1,10]phenanthroline), [Ir(piq)2(maip)]PF6 (Ir2, maip = 3-aminophenyl-1H-imidazo[4,5-f][1,10]phenanthroline) and [Ir(piq)2(paip)]PF6 (Ir3, paip = 4-aminophenyl-1H-imidazo[4,5-f][1,10]phenanthroline). The DNA binding was investigated. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method was used to detect the cytotoxic activity of Ir1, Ir2 and Ir3, the complexes show highly active against B16 cells with IC50 values of 0.3 ± 0.2 µM, 3.7 ± 0.2 µM and 4.6 ± 1.1 µM, respectively. Subsequently, cellular uptake suggested that the cytotoxicity of the complexes is attributed to their differences in cellular uptake levels. In addition, complexes Ir1, Ir2 and Ir3 induce cell cycle arrest at the G0/G1 phase and regulate the cell cycle mediators such as cyclin D1, CDK6 (cyclin-dependent kinase 6), CDK4 and p21, leading to the inhibition of B16 cells proliferation. The autophagy was investigated by monodansylcadaverine (MDC) staining. The complexes can promote the change from LC3-I to LC3-II, up-regulate levels of Beclin-1 and down-regulate expression of p62. The complexes induced apoptosis by regulating the expression levels of related indicators such as PARP (poly ADP-ribose polymerase), PI3K (phosphoinositide-3 kinase), AKT (protein kinase B), Caspase, Bcl-2 (B-cell lymphoma-2), Bad (Bcl2 associated death promoter), Bax (Bcl2-associated X) and Cyto C (cytochrome C). Additionally, Ir1 exerted significant antitumor activity in the suppression of malignant melanoma proliferation in vivo. As indicated in the above results, these complexes were highly effective for malignant melanoma treatment through the intrinsic pathway and provided much insight into anticancer drugs for tumor therapy.

11.
J Biol Inorg Chem ; 26(6): 705-714, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34448071

RESUMO

The study was intended to determine the antineoplastic effects of two new iridium(III) complexes [Ir(ppy)2(PTTP)](PF6) (1) (ppy = 2-phenylpyridine) and [Ir(piq)2(PTTP)](PF6) (2) (piq = 1-phenylisoquinoline, PTTP = 2-phenoxy-1,4,8,9-tetraazatriphenylene). In MTT assay, the ligand PTTP displayed ineffective inhibition on cell growth in SGC-7901, BEL-7402, HepG2 as well as NIH3T3 cell lines, while complexes 1 and 2 showed high cytotoxic activity on SGC-7901 cells with an IC50 value of 0.5 ± 0.1 µM and 4.4 ± 0.6 µM, respectively. Cellular uptake, cell cloning experiments, wound healing assay and cell cycle arrest indicated that the two complexes can inhibit the cell proliferation in SGC-7901 and induce cell cycle arrest at G0/G1 phase. Additionally, reactive oxygen species (ROS) and mitochondrial membrane potential suggested that the two complexes induced cell apoptosis through disrupting mitochondrial functions. Further, western blot analysis illustrated that the two complexes caused apoptosis via regulating expression levels of Bcl-2 family proteins. Moreover, complex 1 could suppress tumor growth in vivo with an inhibitory rate of 49.41%. Altogether, these results demonstrated that complexes 1 and 2 exert a potent anticancer effect against SGC-7901 cells via mitochondrial apoptotic pathway and have a potential to be developed as antineoplastic drug candidates for human gastric cancer.

12.
Rapid Commun Mass Spectrom ; 35(21): e9174, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34350664

RESUMO

RATIONALE: Kaixin San (KXS) is a prescription traditional Chinese medicine (TCM) with the effects of "tonifying the kidney and brain" and "improving memory". The volatile organic compounds (VOCs) in KXS could effectively improve senile dementia and depression, but only few studies have focused on the overall characterization of VOCs in KXS and the quantitative study of the main active components. METHODS: We have developed a strategy to correlate the results from headspace gas chromatography/ion mobility spectrometry (HS-GC/IMS) and headspace gas chromatography/mass spectrometry (HS-GC/MS) for the comprehensive characterization of VOCs in KXS and the quantitative analysis of the main pharmacodynamic substances. RESULTS: A totsal of 68 low molecular weight VOCs were identified in KXS by HS-GC/IMS at room temperature and atmospheric pressure; 117 VOCs were identified and 10 components (isocalamenediol, α-asarone, ß-asarone, methyl eugenol, isoeugenol methyl ether, camphor, anethol, 2,4-di-tert-butylphol, linalool, asarylaldehyde) as the quality markers of KXS based on HS-GC/MS. CONCLUSIONS: This results from this study provide a foundation for quality control, pharmacodynamic mechanism research and further development of KXS, and provides more convincing data supporting the VOCs of other natural products.

13.
J Pharm Pharmacol ; 73(11): 1451-1459, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34379131

RESUMO

OBJECTIVES: As a common step in the herbal medicine production process, percolation usually lacks effective process monitoring methods and is often conducted with fixed process parameters. In this study, an in-line ultraviolet (UV) spectroscopy was used for monitoring the Caulis Sinomenii percolation process. METHODS: The spectra and concentration data of 156 percolation samples from five batches were collected. Convolutional neural networks (CNNs) were used to develop quantitative calibration models. The mean squared error (MSE), mean absolute percentage error (MAPE) and mean absolute error (MAE) were compared to select the proper loss function for developing the CNN models. Meanwhile, partial least square regression (PLSR) was also used to develop calibration models for performance comparison. KEY FINDINGS: The CNN models with MAPE or MAE as the loss function could provide accurate predictions for all samples. However, CNN models adopting MSE as the loss function tended not to predict low-concentration samples accurately. The CNN models mostly achieved satisfactory results without any preprocessing techniques and surpassed PLSR models in all the performance metrics. CONCLUSIONS: An in-line UV spectroscopy system combining the CNN algorithm was implemented to monitor the percolation process of Caulis Sinomenii. The system can accurately determine the endpoint of the percolation process.

14.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(4): 662-670, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34323047

RESUMO

Objective: To analyze the prevalence of diabetes mellitus among middle-aged and older rural adults of Xinxiang county, Henan Province and its correlation with dietary patterns. Methods: The study was done based on the data collected from a cross-sectional survey of Xinxiang County, which was part of the Prospective Cohort Study on the Common Chronic Non-Communicable Diseases in Rural areas of Henan Province. Randomized cluster sampling was used to select adult respondents (≥18 years old) from among the residents of 17 villages in Xinxiang county. The respondents completed questionnaires, and underwent physical examinations and laboratory tests between April, 2017 and June, 2017. A total of 7604 individuals aged between 45 and 79 were included in our study. Dietary patterns were established through factor analysis and the dietary pattern factor scores were divided into quartiles (Q1-Q4). The relationship between dietary patterns and diabetes mellitus was analyzed with multivariate logistic regression model. Results: Out of the total of 7604 middle-aged and older rural adults in Xinxiang County, Henan Province, 1604 had diabetes mellitus, suggesting a 21.1% prevalence of diabetes mellitus. Factor analysis was used to establish four dietary patterns, namely animal-based diet, vegetable-egg diet, mixed diet and traditional diet. Subjects of these four dietary patterns displayed different demographic characteristics. There were no statistical difference in anthropometricor clinical indicators between the quartile with the lowest dietary pattern factor score (Q1) and the quartile with the highest dietary pattern factor score (Q4) for subjects with animal-based diet ( P>0.05). Compared with those in the Q1 quartile of vegetable-egg diet, subjects in the Q4 quartile of vegetable-egg diet showed lower levels of high-density lipoprotein cholesterol (HDL-C), along with different distribution of fasting blood glucose (FBG), showing statistically significant difference ( P<0.05). In comparison to subjects in Q1 quartile of mixed diet, those in Q4 quartile showed lower levels of systolic blood pressure (SBP), the difference being statistically significant ( P<0.05). In the traditional diet group, subjects in the Q4 quartile had lower waist circumference (WC), but higher levels of HDL-C than those of subjects in Q1 quartile. In addition, the distribution of glycated-hemoglobin (HbA1c) and FBG were different, the difference being statistically significant ( P<0.05). The results of multivariate logistic regression analysis demonstrated that traditional diet could be a protective factor of diabetes mellitus (odds ratio [ OR]=0.810, 95% CI: 0.690-0.952, P trend<0.05) after adjusting for multiple confounding factors. Conclusion: The prevalence of diabetes in middle-aged and older rural residents is relatively high in Xinxiang County, Henan Province, and there may be a protective relationship between traditional diet and diabetes mellitus.


Assuntos
Diabetes Mellitus , População Rural , Adolescente , Adulto , Idoso , Animais , China/epidemiologia , Estudos Transversais , Diabetes Mellitus/epidemiologia , Dieta , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
15.
Angew Chem Int Ed Engl ; 60(37): 20331-20341, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34245082

RESUMO

The multimetallic sulfur-framework catalytic site of biological nitrogenases allows the efficient conversion of dinitrogen (N2 ) to ammonia (NH3 ) under ambient conditions. Inspired by biological nitrogenases, a bimetallic sulfide material (FeWSx @FeWO4 ) was synthesized as a highly efficient N2 reduction (NRR) catalyst by sulfur substitution of the surface of FeWO4 nanoparticles. Thus prepared FeWSx @FeWO4 catalysts exhibit a relatively high NH3 production rate of 30.2 ug h-1 mg-1 cat and a Faraday efficiency of 16.4 % at -0.45 V versus a reversible hydrogen electrode in a flow cell; these results have been confirmed via purified 15 N2 -isotopic labeling experiments. In situ Raman spectra and hydrazine reduction kinetics analysis revealed that the reduction of undissociated hydrazine intermediates (M-NH2 -NH2 ) on the surface of the bimetallic sulfide catalyst is the rate-determing step for the NRR process. Therefore, this work can provide guidance for elucidating the structure-activity relationship of NRR catalysts.

16.
Artigo em Inglês | MEDLINE | ID: mdl-34291410

RESUMO

Concomitant with the promotion of industrial transformation, sustainable development strategies, and accelerated urbanization, there has been an increase in the number of industrial relic restoration projects. However, there are many disputes over the value and development of such industrial relic restoration projects. In this work, we identified three evaluation indicators based on a study of 106 industrial relic restoration projects in China. A value assessment model composed of five parts combining the Delphi method and analytic hierarchy process was established. The results show that an effective assessment of the value of industrial relic restoration projects can enable the effective use of green technology, reduce construction costs, protect industrial heritage, and inherit historical culture. In addition, there are many uncertain factors in developing these projects, such as brownfield pollution and dilapidated buildings, and appropriate renewal strategies can reduce safety risks as well as maximize the heritage value. As there is limited research assessing the value of industrial relic restoration projects in China, our study can serve as a reference for the value assessment of existing building restoration projects including historical blocks and livable villages.

17.
Zhongguo Zhong Yao Za Zhi ; 46(11): 2753-2759, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34296572

RESUMO

Through the investigation of a large number of both domestic and overseas literatures and related quality standards, chemical compositions, quality evaluation system and quality control methods of Succus Bambusae were systematic summarized in this study. There were abundant chemical constituents in Succus Bambusae, mainly including volatile ingredients, amino acids, flavonoids, trace elements and vitamins, with high medicinal and edible value. The quality control methods involved traditional morphological identification, spectroscopy, chromatography and other techniques. However, the current quality standards of Succus Bambusae are relatively low, lacking safety indicators, and cannot effectively ensure its quality, seriously affecting the safety and effectiveness of its clinical use. Therefore, it is particularly important to establish a set of highly sensitive and specific quality evaluation system for Succus Bambusae. In this paper, the current research status of the chemical compositions and quality standards of Succus Bambusae were reviewed, with the purpose of providing a basis for further improvement of its quality evaluation system.


Assuntos
Medicamentos de Ervas Chinesas , Flavonoides , Controle de Qualidade
18.
PLoS One ; 16(7): e0254372, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34292979

RESUMO

China is currently designing a regional economic layout for high-quality urban development, shifting its focus from the primary stage of beautifying cities to the next stage of profound urbanization aiming at strengthening industry. This is of high importance given that the urbanization rate of permanent residents by the end of 2019 was 60.60%, according to the National Bureau of Statistics of China. In the face of various factors such as the need to economize the intensive use of resources, urban stock development, and the need for urban constructions to maintain harmony with the surrounding ecosystem, regeneration has emerged as an efficient means to repurpose old residential districts. It conforms to the policy of stock planning and is one of the important methods to ensure the sustainable development of a city. Prioritizing the right attributes in renovation is one of the critical steps in the regeneration of old residential districts-instead of merely focusing on their selection and scoring by experts, more attention should be paid to the resident satisfaction (or the lack thereof) arising from them. Therefore, in this study, we have proposed a collaborative approach that requires communities to prioritize the appropriate aspects in urban renewal. This study employed the three-factor theory of customer satisfaction, to investigate the five attributes namely geographical location, infrastructure, traffic, residential management, and living facilities, of satisfaction and dissatisfaction of residents in the old city. This includes 327 samples based on the residents of Yanta old town in Xi'an. The asymmetric impact-performance analysis technique was used to explore, and quantify the asymmetric relationship between the attributes of old residential districts, and residents' satisfaction. The results proved that attributes were divided into three: excitement factors, performance, and basic factors, based on the asymmetric influence of attributes on residents' satisfaction. Residential management was into excitement factors, living facilities were categorized into basic factors, and the remaining three attributes were categorized into performance factors. The satisfaction of the residents regarding the renovation was maximized by comprehensively considering the performance of given attributes, adjusting the improvement strategies of each attribute, and further determining the focus of the renovation of the old residential districts. Simultaneously, it helped planners make more rational choices in urban renewal and sustainable development.

19.
Nat Plants ; 7(6): 826-841, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34112988

RESUMO

The leaf epidermis is a dynamic biomechanical shell that integrates growth across spatial scales to influence organ morphology. Pavement cells, the fundamental unit of this tissue, morph irreversibly into highly lobed cells that drive planar leaf expansion. Here, we define how tissue-scale cell wall tensile forces and the microtubule-cellulose synthase systems dictate the patterns of interdigitated growth in real time. A morphologically potent subset of cortical microtubules span the periclinal and anticlinal cell faces to pattern cellulose fibres that generate a patch of anisotropic wall. The subsequent local polarized growth is mechanically coupled to the adjacent cell via a pectin-rich middle lamella, and this drives lobe formation. Finite element pavement cell models revealed cell wall tensile stress as an upstream patterning element that links cell- and tissue-scale biomechanical parameters to interdigitated growth. Cell lobing in leaves is evolutionarily conserved, occurs in multiple cell types and is associated with important agronomic traits. Our general mechanistic models of lobe formation provide a foundation to analyse the cellular basis of leaf morphology and function.


Assuntos
Arabidopsis/citologia , Células Vegetais , Folhas de Planta/citologia , Folhas de Planta/crescimento & desenvolvimento , Arabidopsis/crescimento & desenvolvimento , Fenômenos Biomecânicos , Forma Celular , Parede Celular/fisiologia , Celulose/metabolismo , Análise de Elementos Finitos , Microscopia Eletrônica de Transmissão , Microtúbulos/metabolismo , Modelos Biológicos , Mutação , Células Vegetais/metabolismo , Plantas Geneticamente Modificadas , Plasmodesmos
20.
Plant Cell ; 33(9): 3134-3150, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34109391

RESUMO

Plant cell deformations are driven by cell pressurization and mechanical constraints imposed by the nanoscale architecture of the cell wall, but how these factors are controlled at the genetic and molecular levels to achieve different types of cell deformation is unclear. Here, we used stomatal guard cells to investigate the influences of wall mechanics and turgor pressure on cell deformation and demonstrate that the expression of the pectin-modifying gene PECTATE LYASE LIKE12 (PLL12) is required for normal stomatal dynamics in Arabidopsis thaliana. Using nanoindentation and finite element modeling to simultaneously measure wall modulus and turgor pressure, we found that both values undergo dynamic changes during induced stomatal opening and closure. PLL12 is required for guard cells to maintain normal wall modulus and turgor pressure during stomatal responses to light and to tune the levels of calcium crosslinked pectin in guard cell walls. Guard cell-specific knockdown of PLL12 caused defects in stomatal responses and reduced leaf growth, which were associated with lower cell proliferation but normal cell expansion. Together, these results force us to revise our view of how wall-modifying genes modulate wall mechanics and cell pressurization to accomplish the dynamic cellular deformations that underlie stomatal function and tissue growth in plants.

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