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1.
Chemistry ; 26(4): 888-899, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31696989

RESUMO

The anion-binding and transport properties of an extensive library of thiophene-based molecules are reported. Seventeen bis-urea positional isomers, with different binding conformations and lipophilicities, have been synthesized by appending α- or ß-thiophene or α-, ß-, or γ-benzo[b]thiophene moieties to an ortho-phenylenediamine central core, yielding six subsets of positional isomers. Through 1 H NMR, X-ray crystallography, molecular modelling, and anion efflux studies, it is demonstrated that the most active transporters adopt a pre-organized binding conformation capable of promoting the recognition of chloride, using urea and C-H binding groups in a cooperative fashion. Additional large unilamellar vesicle-based assays, carried out under electroneutral and electrogenic conditions, together with N-methyl-d-glucamine chloride assays, have indicated that anion efflux occurs mainly through an H+ /Cl- symport mechanism. On the other hand, the most efficient anion transporter displays cytotoxicity against tumor cell lines, while having no effects on a cystic fibrosis cell line.

2.
J Org Chem ; 85(2): 493-500, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31845809

RESUMO

A highly efficient synthetic method for the preparation of 2-aminobenzothiazoles starting from arylthioureas has been reported. By using a nickel catalyst, arylthioureas undergo intramolecular oxidative C-H bond functionalization, giving the desired 2-aminobenzothiazoles in good to excellent yields. This protocol features an inexpensive catalyst, low catalyst loading, mild reaction conditions, a short reaction time, and good to excellent yields, and it can be scaled up easily to a gram scale with almost no yields decreasing.

3.
Sci Rep ; 9(1): 16421, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31712559

RESUMO

Quantum key agreement (QKA) is to negotiate a final key among several participants fairly and securely. In this paper, we show that some existing travelling-mode multiparty QKA protocols are vulnerable to internal participant's attacks. Dishonest participants can exploit a favorable geographical location or collude with other participants to predetermine the final keys without being discovered. To resist such attacks, we propose a new travelling-mode multiparty QKA protocol based on non-orthogonal Bell states. Theoretical analysis shows that the proposed protocol is secure against both external and internal attacks, and can achieve higher efficiency compared with existing travelling-mode multiparty QKA protocols. Finally we design an optical platform for each participant, and show that our proposed protocol is feasible with current technologies.

4.
Int. braz. j. urol ; 45(5): 916-924, Sept.-Dec. 2019. graf
Artigo em Inglês | LILACS-Express | ID: biblio-1040072

RESUMO

ABSTRACT Objective This study aims to investigate the association of filamin A with the function and morphology of prostate cancer (PCa) cells, and explore the role of filamin A in the development of PCa, in order to analyze its significance in the evolvement of PCa. Materials and Methods A stably transfected cell line, in which filamin A expression was suppressed by RNA interference, was first established. Then, the effects of the suppression of filamin A gene expression on the biological characteristics of human PCa LNCaP cells were observed through cell morphology, in vitro cell growth curve, soft agar cloning assay, and scratch test. Results A cell line model with a low expression of filamin A was successfully constructed on the basis of LNCaP cells. The morphology of cells transfected with plasmid pSilencer-filamin A was the following: Cells were loosely arranged, had less connection with each other, had fewer tentacles, and presented a fibrous look. The growth rate of LNCap cells was faster than cells transfected with plasmid pSilencer-filamin A (P <0.05). The clones of LNCap cells in the soft agar cloning assay was significantly fewer than that of cells stably transfected with plasmid pSilencer-filamin A (P <0.05). Cells stably transfected with plasmid pSilencer-filamin A presented with a stronger healing and migration ability compared to LNCap cells (healing rate was 32.2% and 12.1%, respectively; P <0.05). Conclusion The expression of the filamin A gene inhibited the malignant development of LNCap cells. Therefore, the filamin A gene may be a tumor suppressor gene.

5.
Chem Commun (Camb) ; 55(74): 11119-11122, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31461096

RESUMO

A new heterometallic macrocycle with photochromic properties was succesfully constructed through coordination-driven self-assembly, which features interesting photoswitchable Förster resonance energy transfer (FRET) behaviour.

6.
Int Braz J Urol ; 45(5): 916-924, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31268639

RESUMO

OBJECTIVE: This study aims to investigate the association of filamin A with the function and morphology of prostate cancer (PCa) cells, and explore the role of filamin A in the development of PCa, in order to analyze its significance in the evolvement of PCa. MATERIALS AND METHODS: A stably transfected cell line, in which filamin A expression was suppressed by RNA interference, was first established. Then, the effects of the suppression of filamin A gene expression on the biological characteristics of human PCa LNCaP cells were observed through cell morphology, in vitro cell growth curve, soft agar cloning assay, and scratch test. RESULTS: A cell line model with a low expression of filamin A was successfully constructed on the basis of LNCaP cells. The morphology of cells transfected with plasmid pSilencer-filamin A was the following: Cells were loosely arranged, had less connection with each other, had fewer tentacles, and presented a fibrous look. The growth rate of LNCap cells was faster than cells transfected with plasmid pSilencer-filamin A (P<0.05). The clones of LNCap cells in the soft agar cloning assay was significantly fewer than that of cells stably transfected with plasmid pSilencer-filamin A (P<0.05). Cells stably transfected with plasmid pSilencer-filamin A presented with a stronger healing and migration ability compared to LNCap cells (healing rate was 32.2% and 12.1%, respectively; P<0.05). CONCLUSION: The expression of the filamin A gene inhibited the malignant development of LNCap cells. Therefore, the filamin A gene may be a tumor suppressor gene.


Assuntos
Filaminas/análise , Filaminas/fisiologia , Neoplasias da Próstata/patologia , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células , Células Cultivadas , Colorimetria/métodos , Filaminas/genética , Formazans , Humanos , Masculino , Plasmídeos , Neoplasias da Próstata/genética , Sais de Tetrazólio , Fatores de Tempo , Transfecção/métodos , Cicatrização/fisiologia
7.
Chem Sci ; 10(18): 4896-4904, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31160961

RESUMO

Discrete, well-defined metallacycles and metallacages with stimuli-responsive behaviors have been largely predominated by the organic donor/metal acceptor paradigm with spontaneous formation of coordination bonds. However, light-driven self-assembly systems usually show relatively low utilization yield of photons and low fatigue resistance. Given that almost no example illustrates the different self-assembly behaviors of antiparallel and parallel conformers in the traditional photochromic diarylethene (DAE) system, here we have for the first time constructed a unique series of photoactive conformer-dependent metallacycles, focusing on the characterization and comparison of self-assembly behavior in different ligand conformers with different di-platinum(ii) acceptors. Their photoswitchable scaffold sizes and shapes are precisely controlled by photochromically separable parallel or anti-parallel conformers via coordination-driven self-assembly. The ap-conformer and closed form provide larger bending angles upon coordination with di-Pt(ii) acceptors into hexagon [6 + 6] or [3 + 3] while the p-conformer only can form smaller polygon cycles. Notably, in contrast with the non-photoactive parallel conformer, the reversible interconversion of anti-parallel ring-open and ring-closed conformer metallacycles can be achieved by alternate irradiation with UV and visible light, respectively, along with a relatively high conversion ratio and good fatigue resistance. This work provides a potential way to construct smart materials for use in sensing, catalysis and drug delivery systems.

8.
Mol Phylogenet Evol ; 139: 106542, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31229601

RESUMO

Goodyerinae are one of the most species-rich and widespread subtribes of Orchidaceae but notorious for their taxonomic difficulty. Here, a comprehensive molecular phylogenetic study of the subtribe is presented based on two nuclear (ITS, Xdh) and five plastid (matK, psaB, rbcL, trnL, trnL-F) regions. A total of 119 species were included representing all clades recovered by previous phylogenetic analyses as well as seven outgroups. Maximum parsimony, maximum likelihood and Bayesian inference methods were used to infer the phylogenetic relationships. The results show that the Goodyerinae subdivided into three major subdivisions and six groupings: Pachyplectron, Goodyera clade (including Goodyera procera, Microchilus subclade and Goodyera subclade) and Cheirostylis clade (including Gonatostylis, Cheirostylis subclade and Ludisia subclade). Four genera, Erythrodes, Goodyera, Myrmechis and Odontochilus, are not monophyletic. The results support Odontochilus s. l. to include Myrmechis and Kuhlhasseltia. The systematic positions of Goodyera procera and two isolated genera, Herpysma and Orchipedum, are difficult to determine.

9.
J Am Chem Soc ; 141(22): 8943-8950, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31088049

RESUMO

Noninvasive control over the reversible generation of singlet oxygen (1O2) has found the practical significance in benefiting photodynamic therapy. In this study, we developed a new dual-stage metallacycle (M) by using a photosensitizer and photochromic switch as the functional building blocks, which enables the noninvasive "off-on" switching of 1O2 generation through the efficient intramolecular energy transfer. Due to the proximal placement of the functional entities within the well-defined metallacyclic scaffold, 1O2 generation in the ring-closed form state of the photochromic switch (C-M) is quenched by photoinduced energy transfer, whereas the generation of 1O2 in the ring-open form state (O-M) is activated upon light irradiation. More interestingly, the metallacycle-loaded nanoparticles with relatively high stability and water solubility were prepared, which allow for the delivery of metallacycles to cancer cells via endocytosis. Their theranostic potential has been systematically investigated both in vitro and in vivo. Under the light irradiation, the designed ring-open form nanoparticles (O-NPs) show remarkable higher cytotoxicity against cancer cells compared to the ring-closed form nanoparticles (C-NPs). In vivo experiments also revealed that tumors can be very efficiently eliminated by the designed nanoparticles under light irradiation with the ability to regulate in vivo generation of singlet oxygen. All these results demonstrated that the supramolecular coordination complexes with a dual-stage state provide a highly efficient nanoplatform for noninvasive control over the reversible generation of 1O2, thus allowing for their promising applications in tumor treatment and beyond.

10.
J Med Ultrason (2001) ; 46(3): 335-341, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30790093

RESUMO

PURPOSE: To review the imaging characteristics and evaluate the diagnostic value of echocardiography for diagnosing anomalous origin of the right coronary artery from the pulmonary artery (ARCAPA). METHODS: We retrospectively reviewed the echocardiographic records and compared these images with operative findings in six children with ARCAPA. RESULTS: ARCAPA was characterized by dilation of the left coronary artery, inappropriate origin of the right coronary artery from the pulmonary artery, and collaterals within the interventricular septum. The associated malformations included atrial septal defect in four cases. Four of six cases were diagnosed correctly, while the remaining two cases were misdiagnosed: one of fistula between the pulmonary artery and the left coronary artery and another of ARCAPA diagnosed intraoperatively in one case of atrial septal defect. CONCLUSION: ARCAPA can be diagnosed by echocardiography but is prone to misdiagnosis. This malformation should be distinguished from coronary artery fistula.


Assuntos
Anomalias dos Vasos Coronários/diagnóstico por imagem , Ecocardiografia , Artéria Pulmonar/anormalidades , Artéria Pulmonar/diagnóstico por imagem , Adolescente , Fístula Artério-Arterial/diagnóstico por imagem , Criança , Pré-Escolar , Erros de Diagnóstico , Feminino , Comunicação Interatrial/diagnóstico por imagem , Humanos , Lactente , Masculino , Estudos Retrospectivos
11.
Curr Med Res Opin ; 35(2): 203-210, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29611724

RESUMO

OBJECTIVE: Ventricular function assessment is very important for the treatment and prognostic classification of children with a single right ventricle (SRV) after cavopulmonary anastomosis (CPA). However, unusual ventricular shapes can result in inaccurate measurements. The aim of this study was to evaluate velocity vector imaging (VVI) for assessing segmental ventricular function in children with SRV after CPA. METHODS: Twenty-one children with SRV after CPA and 21 age- and sex-matched children with normal biventricular anatomy and function were included. The longitudinal velocity, displacement, strain and strain rate were measured in the two groups in six segments by VVI. The velocity, displacement, strain and strain rate of the SRVs were compared with max(dp/dt) measured during simultaneous cardiac catheterization in the SRV subjects. RESULTS: The control group consisted of 13 males and 8 females (69% males) with a mean age of 6.7 ± 3.5 years and mean weight of 20.5 ± 6.5 kg, and the study group consisted of 13 males and 8 females with a mean age 6.7 ± 3.7 years and mean weight of 20.6 ± 6.8 kg. Age, weight and sex distribution were similar between the groups (all, p > .05). Strain and strain rate values in all six segments were significantly lower in the study group than in the control group (all, p < .05). The max(dp/dt) of the SRV was 522.84 ± 158.32 mmHg/s, and the strain rate of the basal segment at the rudimentary chamber correlated best with max(dp/dt) (r = 0.74, p < .01). CONCLUSIONS: Segmental ventricular dysfunction was present in children with SRV after CPA, and it could be assessed using VVI.


Assuntos
Derivação Cardíaca Direita/métodos , Ventrículos do Coração/diagnóstico por imagem , Função Ventricular/fisiologia , Cateterismo Cardíaco/métodos , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Prognóstico
12.
Echocardiography ; 36(1): 133-141, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30515879

RESUMO

BACKGROUND: Challenges remain in quantitative evaluation of right ventricular (RV) function by echocardiography. Multiple-view assessment is believed to provide a more comprehensive quantification of RV function than conventional single-view analysis. Peak systolic longitudinal RV strain (RVLS) measured by speckle tracking echocardiography (STE) has clinical and prognostic value. No study has investigated RV systolic function in the repaired tetralogy of Fallot (rTOF) using a standardized four-view iRotate model from one apical view. Herein, we examined the feasibility and accuracy of the four-view analysis from apical window in quantitation of RVLS among children with rTOF. METHODS: Thirty-seven children with rTOF and 37 age- and gender-matched controls were prospectively enrolled. Tricuspid annular plane systolic excursion (TAPSE) and tricuspid annular peak systolic velocity (TDI-S' ) and fractional area change(FAC) were obtained. RVLS of four free-walls were analyzed by dedicated RV speckle tracking software. Echocardiographic parameters were compared with the right ventricular ejection fraction (RVEF) measured by the cardiac magnetic resonance (CMR) in children with rTOF. RESULTS: Multi-view RVLS analysis from apical window was feasible in 35 children with rTOF and all the controls. Compared with age- and gender-matched controls, RVLS of the anterior, lateral, inferior-a, and inferior-b walls were significantly reduced in children with rTOF (P < 0.001). RVLS of the anterior, lateral, inferior-a, and inferior-b walls correlated well with CMR-RVEF in children with rTOF (r = -0.667, -0.743, -0.808, -0.695, P < 0.001). CONCLUSIONS: Multi-view analysis of RVLS from apical window can be applied to evaluate the RV function in children with rTOF. RVLS of the inferior wall-a in the aortic view is a novel and accurate indicator of RV function because of its good reproducibility and strong correlation with CMR-RVEF.


Assuntos
Ecocardiografia/métodos , Complicações Pós-Operatórias/diagnóstico por imagem , Tetralogia de Fallot/cirurgia , Disfunção Ventricular Direita/diagnóstico por imagem , Pré-Escolar , Estudos de Viabilidade , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Lactente , Masculino , Estudos Prospectivos , Reprodutibilidade dos Testes , Disfunção Ventricular Direita/fisiopatologia , Função Ventricular Direita/fisiologia
13.
J Asian Nat Prod Res ; 21(4): 331-336, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29334258

RESUMO

Two new phenylpropanoid esters bobulretulates A (1) and B (2), together with eleven known compounds, were isolated from the whole plants of Bulbophyllum retusiusculum. Their structures were elucidated by means of extensive spectroscopic analysis.


Assuntos
Orchidaceae/química , Fenilpropionatos/isolamento & purificação , Ésteres/química , Ésteres/isolamento & purificação , Fenilpropionatos/química
14.
J Asian Nat Prod Res ; 21(2): 129-133, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29069925

RESUMO

Two new picrotoxane-type sesquiterpenoid lactones, dendrowillins A (1) and B (2), together with five known sesquiterpenoids, (-)-picrotin (3), α-dihydropicrotoxinin (4), dendronobilin B (5), amoenin (6), and (-)-10ß,13,14-trihydroxyalloaromadendrane (7), were isolated from the whole plants of Dendrobium williamsonii. Their structures were elucidated by means of extensive spectroscopic analysis.


Assuntos
Dendrobium/química , Lactonas/química , Sesquiterpenos/química , Estrutura Molecular
15.
Inorg Chem ; 57(24): 15414-15420, 2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30521327

RESUMO

A new discrete hexagonal metallacycle M containing tris-[2]pseudorotaxane moiety has been successfully designed and synthesized via coordination-driven self-assembly. The newly designed tris-[2]pseudorotaxane metallacycle was well characterized with nuclear magnetic resonance and mass spectra analysis. Such tris-[2]pseudorotaxane metallacycle M and pillar[5]arene dimer (PD) could further form a new family of cross-linked redox-responsive supramolecular polymer M⊃(PD)3 through a host-guest interaction. Interestingly, the polymer M⊃(PD)3 displayed redox-responsive behavior and showed tuned weight-average diffusion coefficients D upon redox stimuli, which is attributed to the changed coordination geometries of [Cu(phen)2]+ and [Cu(phen)2]2+ in such system.

16.
Acc Chem Res ; 51(11): 2699-2710, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30285407

RESUMO

Supramolecular self-assembly, which creates the ordered structures as a result of spontaneous organization of building blocks driven by noncovalent interactions (NCIs), is ubiquitous in nature. Recently, it has become increasingly clear that nature often builds up complex structures by employing a hierarchical self-assembly (HSA) strategy, in which the components are brought together in a stepwise process via multiple NCIs. Inspired by the dedicated biological structures in nature, HSA has been widely explored to construct well-defined assemblies with increasing complexity. The employment of direct metal-ligand bonds to drive the formation of discrete metallosupramolecular architectures has proven to be a highly efficient strategy to prepare structurally diverse architectures like two-dimensional (2-D) polygons and three-dimensional (3-D) polyhedra with well-defined shapes, sizes, and geometries. Such well-defined organometallic assemblies provide an ideal platform for designing novel artificial supramolecular systems with the increasing complexity though HSA. The presence of a well-defined organometallic scaffold brings an additional dimension to the final nanoscale structures. Moreover, the multilevel dynamic nature of hierarchical self-assemblies brings more structural and functional possibilities of resultant supramolecular systems. This Account will focus on our recent advance on construction of stimuli-responsive functional materials through HSA involving coordination interactions. In our study, a series of functionalized metallacycles were first constructed through coordination-driven self-assembly (CDSA). Then, the secondary noncovalent interaction sites were integrated within the functionalized metallacycle system via either preassembly or postassembly approach. Different segments, such as alkyl chains, dendrimers, cholesteryl moiety, covalent macrocycles, and even polymeric fragments, which could provide hydrophobic and hydrophilic interactions, van der Waals forces, hydrogen bonding, CH-π and π-π interactions, and host-guest interactions, have been utilized to provide the secondary NCIs. Further self-assembly of functionalized metallacycles gives rise to the formation of complex higher-order structures driven by other NCIs by taking advantages of orthogonal property of coordination bonds with other NCIs. By changing the type of additional NCIs embodied in building blocks, different supramolecular architectures, such as the ordered nanostructures, supramolecular polymers and gels, fluorescent materials and sensors, have been successfully prepared with the tailored chemical and physical properties. In particular, the dynamic nature of coordination bonds as well as other NCIs endows final assemblies with stimuli-responsive functions. Collectively, our studies suggest that combining coordination and other NCIs in a well-defined and precise manner is a highly efficient strategy to achieve the complex architectures and functional materials. Therefore, it is very promising to develop the desired functional materials with high precision and fidelity by employing HSA involving coordination interactions.

17.
Ying Yong Sheng Tai Xue Bao ; 29(10): 3221-3228, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30325146

RESUMO

Studies on effects of nitrogen deposition were mainly focused on temperate grasslands in Inner Mongolia of China. In addition, there are substantial differences between the present simulation methods and the natural nitrogen deposition. A three-year experiment was carried out to compare the effects of simulation methods (common urea and slow-released urea) and nitrogen deposition rates (0, 25, 50, 75, 100, 150, 200 and 300 kg N·hm-2·a-1) on soil nutrients and biological characteristics in Hulun Buir Grassland. We found that simulated nitrogen deposition had significant influences on soil chemical properties, biological properties and enzyme activities. With the increases of nitrogen deposition, soil pH declined with the greatest extent of 0.2 units, while the highest concentrations of total dissolved nitrogen (TDN) and dissolved organic carbon (DOC) increased by 5-7 times and 12%-36%, respectively. There was a decline trend for soil total phosphorus (TP) and organic phosphorus (TOP). Microbial biomass and metabolic activity increased firstly and then decreased. Moderate simulated nitrogen deposition rates significantly increased soil carbon, nitrogen and phosphorus related enzyme activities. Compared to common urea, using slow-released urea to simulate nitrogen deposition decelerate the decline of soil pH and the increase of dissolved nutrients, and smoothed the change of microbial biomass, metabolic activity, and nitrogen hydrolyzed enzyme activities. Overall, the results confirmed that continuous nitrogen input caused the decline of soil pH and the increase of bioavailable carbon and nitrogen, and then changed microbial biomass and activity.


Assuntos
Solo , Biomassa , Carbono , China , Alimentos , Pradaria , Nitrogênio , Fósforo , Microbiologia do Solo , Ureia
18.
FEBS Open Bio ; 8(9): 1508-1523, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30186751

RESUMO

Integrated studies of accumulated data can be performed to obtain more reliable information and more feasible measures for investigating potential diagnostic biomarkers of gastric cancer (GC) and to explore related molecular mechanisms. This study aimed to identify microRNAs involved in GC by integrating data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus. Through our analysis, we identified hsa-miR-17 (miR-17) as a suitable candidate. We performed a meta-analysis of published studies and analyzed clinical data from TCGA to evaluate the clinical significance and diagnostic value of miR-17 in GC. miR-17 was found to be upregulated in GC tissues and exhibited a favorable value in diagnosing GC. In addition, we predicted that 288 target genes of miR-17 participate in GC-related pathways. Enrichment of Kyoto Encyclopedia of Genes and Genomes pathway, Gene Ontology analysis, and protein-protein interaction analysis of the 288 target genes of miR-17 were also performed. Through this study, we identified possible core pathways and genes that may play an important role in GC. The possible core pathways include the cAMP, phosphoinositide-3-kinase-Akt, Rap1, and mitogen-activated protein kinase signaling pathways. miR-17 may be involved in several biological processes, including DNA template transcription, the regulation of transcription from RNA polymerase II promoters, and cell adhesion. In addition, cellular components (such as cytoplasm and plasma membrane) and molecular functions (such as protein binding and metal ion binding) also seemed to be regulated by miR-17.

19.
Ying Yong Sheng Tai Xue Bao ; 29(8): 2470-2476, 2018 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-30182584

RESUMO

Soil organic C, N, P contents and their catalyzed enzyme activities play an important role in maintaining and supplying energy and nutrient in grasslands. There is no consensus on the effects of N deposition on soil organic nutrients and enzyme activities in grassland ecosystems. It remains unclear whether C addition will retard the negative effects of N deposition. We carried out an experiment in Hulun Buir grassland of Inner Mongolia to examine the effects of C and N additions on soil organic C, N, P and relative enzyme activities after three years treatments. The experiment was conducted with N treatments at five levels (0, 25, 50, 100 and 200 kg·hm-2·a-1) and with C treatments at three levels (0, 250 and 500 kg·hm-2·a-1). The results showed that higher levels of N addition significantly decreased dehydrogenase (DHA) and ß-1,4-N-acetylglucosaminidase (NAG) activities by 22.3% and 12.5%, respectively. Nitrogen addition had no significant effect on soil organic N and decreased the organic C and P contents by 6.6% and 14.5%, respectively. High C addition significantly increased DHA, ß-glucosidase (BG) activities and increased soil organic N and organic P by 15.1%, 12.2%, 1.9%, 2.6%, respectively. The results suggested that continuous N inputs inhibited microbial activities and caused losses of soil organic C and organic P. Carbon addition could enhance microbial activities and promote the secretion of enzymes and increase soil organic N and P. The combined C and N addition could play an important role in maintaining the balance and supply of soil C, N, and P in grassland ecosystem.


Assuntos
Carbono/metabolismo , Pradaria , Nitrogênio/metabolismo , Fósforo/metabolismo , China , Ecossistema , Enzimas , Solo , Microbiologia do Solo
20.
Sci Rep ; 8(1): 14263, 2018 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-30250207

RESUMO

Sleep disturbance is a common complaint in cancer patients. However, less is known about the parameters of sleep in patients with nasopharyngeal cancer (NPC) and their family caregivers (FCs) when they are about to begin treatment. We investigated the sleep quality in patients with NPC and their FCs before treatment and determined the related factors that predict sleep disturbance in these patients before therapy. A total of 101 patient-FC dyads were recruited. They completed the Pittsburgh Sleep Quality Index (PSQI) prior to treatment. No differences were found in sleep disturbance between patients (38.6%) and their FCs (31.7%). Patients reported significantly higher rates of short sleep duration than their FCs (P = 0.011). Logistic regression analyses showed that older patients were more prone to suffer from poor sleep quality before treatment (OR = 1.06, 95% CI = 1.01-1.10, P = 0.008), while patients with a higher BMI were less likely to experience sleep disturbance (OR = 0.83, 95% CI = 0.71-0.96, P = 0.012). Sleep disturbance is a significant problem in patients with NPC and their FCs before therapy. Older patients and those with a lower BMI appear to be more inclined to suffer from poor sleep before treatment.


Assuntos
Cognição/fisiologia , Carcinoma Nasofaríngeo/epidemiologia , Transtornos do Sono-Vigília/epidemiologia , Sono/fisiologia , Adulto , Idoso , Cuidadores/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/complicações , Carcinoma Nasofaríngeo/patologia , Transtornos do Sono-Vigília/complicações , Transtornos do Sono-Vigília/patologia
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