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1.
PLoS One ; 19(5): e0304419, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38820482

RESUMO

In recent years, various data-driven algorithms have been applied to the classification and staging of brain glioma MRI detection. However, the restricted availability of brain glioma MRI data in purely data-driven deep learning algorithms has presented challenges in extracting high-quality features and capturing their complex patterns. Moreover, the analysis methods designed for 2D data necessitate the selection of ideal tumor image slices, which does not align with practical clinical scenarios. Our research proposes an novel brain glioma staging model, Medical Cognition Embedded (MCE) model for 3D data. This model embeds knowledge characteristics into data-driven approaches to enhance the quality of feature extraction. Approach includes the following key components: (1) Deep feature extraction, drawing upon the imaging technical characteristics of different MRI sequences, has led to the design of two methods at both the algorithmic and strategic levels to mimic the learning process of real image interpretation by medical professionals during film reading; (2) We conduct an extensive Radiomics feature extraction, capturing relevant features such as texture, morphology, and grayscale distribution; (3) By referencing key points in radiological diagnosis, Radiomics feature experimental results, and the imaging characteristics of various MRI sequences, we manually create diagnostic features (Diag-Features). The efficacy of proposed methodology is rigorously evaluated on the publicly available BraTS2018 and BraTS2020 datasets. Comparing it to most well-known purely data-driven models, our method achieved higher accuracy, recall, and precision, reaching 96.14%, 93.4%, 97.06%, and 97.57%, 92.80%, 95.96%, respectively.


Assuntos
Algoritmos , Neoplasias Encefálicas , Glioma , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Glioma/diagnóstico por imagem , Glioma/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Imageamento Tridimensional/métodos , Estadiamento de Neoplasias , Aprendizado Profundo , Cognição , Interpretação de Imagem Assistida por Computador/métodos
2.
Inorg Chem ; 61(47): 18950-18956, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36378122

RESUMO

Reversible covalent reactions within crystalline complexes are powerful tools for the design and developing of new generation of reusable smart materials. In this work, a unique photoreactive olefin-containing metal-organic coordination polymer [Ag2(2,3-ppe)2(1,3-bdc)]n (1) was prepared by the hydrothermal reaction between AgNO3, 1-(2-pyridyl)-2-(3-pyridyl)ethylene (2,3-ppe), and 1,3-benzenedicarboxylic acid (1,3-H2bdc). When exposed to sunlight, 1 can undergo single-crystal-to-single-crystal (SCSC) transformation to form [Ag2(dpdpcb)(1,3-bdc)]n (1a, dpdpcb = 1,3-di(2-pyridyl)-2,4-di(3-pyridyl)cyclobutane) through a [2 + 2] cycloaddition reaction. 1a can regenerate into 1 via the cycloreversion reaction based on the thermal effect of sunlight. Such a metal-organic complex exhibits interesting fluorescence switching behavior during the unprecedented fully solar-controlled reversible SCSC reaction, which makes it possible to be applied to the fields of optical memory storage and anti-counterfeiting.

3.
Dalton Trans ; 51(45): 17235-17240, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36314637

RESUMO

Photoreactive coordination polymers are particularly important media for the implementation of highly-selective photoreactions and creation of photoresponsive intelligent materials and devices. Herein, a two-dimensional (2D) photoreactive coordination polymer, formulated as [Cd(pha)(3,3'-bpe)]n (1) was prepared through the hydrothermal reaction between Cd(NO3)2·4H2O, phthalic acid (H2pha) and 1,2-bis(3-pyridyl)ethylene (3,3'-bpe). Upon exposure to 365 nm UV light, the 1H NMR spectroscopy and single crystal X-ray diffraction analysis results indicated that 1 can undergo a [2 + 2] photocycloaddition reaction and thus form a new coordination polymer [Cd(pha)(3,3'-tpcb)0.5]n (1a) through single-crystal to single-crystal (SCSC) transformation. Accompanied by the SCSC photoreaction, the 2D sql net of 1 converted into a 2D binodal network of 1a with the rare (324·627)(326272) topology. The SCSC transformation from 1 to 1a also exhibits an interesting photocontrolled fluorescence. The unique photoinduced structural change and fluorescence quenching of 1 makes it a potential intelligent material for optical anti-counterfeiting, fluorescence sensors and other fields.

4.
Inorg Chem ; 61(5): 2463-2475, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35073687

RESUMO

Functional materials with stable and adjustable luminescence have recently become a research hotspot for their broad application prospects. Tunable luminescence can be realized by the doping of hetero-valent europium ions. High-temperature hydrogen atmosphere reduction is required in the traditional preparation of Eu2+-doped phosphors. Herein, an anoxic molten-salt medium environment was established to form oxygen vacancy defects in the reaction system and induce the self-reduction of Eu3+ ions to obtain Eu2+ ions. X-ray photoelectron spectroscopy (XPS) results confirm the existence of Eu2+ and Eu3+ ions in the samples, and the fluorescence spectrum shows that hetero-valent Eu ions can synergistically emit light effectively. Under 266 nm ultraviolet light excitation, the white light emission was successfully realized for a Ba2InTaO6:Eu phosphor by different emission combinations of Eu3+ and Eu2+ ions. In addition, the Ba2InTaO6:Eu phosphor exhibits adjustable luminescence from greenish-yellow to red exciting at 390-490 nm, which has superior stability in a high-temperature and high-humidity environment. Therefore, it is very promising that Ba2InTaO6:Eu will be used as multi-color functional materials in many fields such as communication encryption and colorful decoration.

5.
Mitochondrial DNA B Resour ; 6(11): 3171-3173, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34746395

RESUMO

The complete chloroplast (cp) genome of Corydalis fangshanensis W.T. Wang ex S.Y. He, a Chinese endemic plant with limestone-specific distribution was first reported. The cp genome was circular in structure and 192,554 bp in length, consisting of a large single copy region (LSC, 98,393 bp), two inverted repeat regions (IRs, 42,263 bp), and a small single copy region (SSC, 9,635 bp). The overall GC content of the genome was 40.26%. It encoded 112 unique genes, including 78 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. Phylogenetic analysis resolved C. fangshanensis was closely related to C. saxicola G.S. Bunting within Corydalis sect. Thalictrifoliae (Fedde) Lidén, in line with morphological character-based taxonomy. Our result provides informative data for studying the taxonomy, phylogeny and ecology of Corydalis, especially species with specific-limestone distribution and also for studying the adaptive evolution in plants.

6.
Inorg Chem ; 60(22): 17173-17177, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34714643

RESUMO

Stimuli-responsive solids with adjustable photophysical properties are particularly attractive because they can be used as smart materials in anticounterfeiting, information storage, holographic imaging, and other fields. Herein, we report a unique nonporous coordination polymer, {[Ag(3,3'-dpe)](2,2'-Hbpdc)}n (1; 3,3'-dpe = 1,2-dipyridin-3-ylethene and 2,2'-H2bpdc = 2,2'-biphenyldicarboxylic acid), that can convert to an extremely photoreactive compound, 1·H2O·MeCN (MeCN = acetonitrile), through guest capture. Upon irradiation of sunlight, 1·H2O·MeCN can transform to {[Ag(3,3'-tpcb)0.5](2,2'-Hbpdc)(H2O)(MeCN)}n (2·H2O·MeCN; 3,3'-tpcb = 1,2,3,4-tetrapyridin-3-ylcyclobutane). 2·H2O·MeCN can lose its solvent molecules to form 2 and further return to 1 at high temperature. Accompanied by direct visualization based on multistep single-crystal-to-single-crystal conversions, the recyclable crystalline solid exhibits remarkable fluorescence changes, which makes it a supramolecular switch for application in multiple anticounterfeiting.

7.
ACS Infect Dis ; 7(8): 2565-2582, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34346692

RESUMO

Biofilms, structured communities of bacterial cells embedded in a self-produced extracellular matrix (ECM) which consists of proteins, polysaccharide intercellular adhesins (PIAs), and extracellular DNA (eDNA), play a key role in clinical infections and are associated with an increased morbidity and mortality by protecting the embedded bacteria against drug and immune response. The high levels of antibiotic tolerance render classical antibiotic therapies impractical for biofilm-related infections. Thus, novel drugs and strategies are required to reduce biofilm tolerance and eliminate biofilm-protected bacteria. Here, we showed that gallium, an iron mimetic metal, can lead to nutritional iron starvation and act as dispersal agent triggering the reconstruction and dispersion of mature methicillin-resistant Staphylococcus aureus (MRSA) biofilms in an eDNA-dependent manner. The extracellular matrix, along with the integral bacteria themselves, establishes the integrated three-dimensional structure of the mature biofilm. The structures and compositions of gallium-treated mature biofilms differed from those of natural or antibiotic-survived mature biofilms but were similar to those of immature biofilms. Similar to immature biofilms, gallium-treated biofilms had lower levels of antibiotic tolerance, and our in vitro tests showed that treatment with gallium agents reduced the antibiotic tolerance of mature MRSA biofilms. Thus, the sequential administration of gallium agents (gallium porphyrin and gallium nitrate) and relatively low concentrations of vancomycin (16 mg/L) effectively eliminated mature MRSA biofilms and eradicated biofilm-enclosed bacteria within 1 week. Our results suggested that gallium agents may represent a potential treatment for refractory biofilm-related infections, such as prosthetic joint infections (PJI) and osteomyelitis, and provide a novel basis for future biofilm treatments based on the disruption of normal biofilm-development processes.


Assuntos
Gálio , Staphylococcus aureus Resistente à Meticilina , Porfirinas , Biofilmes , DNA , Gálio/farmacologia , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Vancomicina/farmacologia
8.
Tree Physiol ; 41(5): 756-770, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33105484

RESUMO

Maintaining mitochondrial respiration is crucial for proving ATP for H+ pumps to continuously exclude Na+ under salt stress. NaCl-altered O2 uptake, mitochondrial respiration and the relevance to H+-ATPase activity were investigated in two contrasting poplar species, Populus euphratica (salt-tolerant) and Populus popularis 35-44 (salt-sensitive). Compared with P. popularis, P. euphratica roots exhibited a greater capacity to extrude Na+ under NaCl stress (150 mM). The cytochemical analysis with Pb(NO3)2 staining revealed that P. euphratica root cells retained higher H+ hydrolysis activity than the salt-sensitive poplar during a long term (LT) of increasing salt stress (50-200 mM NaCl, 4 weeks). Long-sustained activation of proton pumps requires long-lasting supply of energy (adenosine triphosphate, ATP), which is delivered by aerobic respiration. Taking advantage of the vibrating-electrodes technology combined with the use of membrane-tipped, polarographic oxygen microelectrodes, the species, spatial and temporal differences in root O2 uptake were characterized under conditions of salt stress. Oxygen uptake upon NaCl shock (150 mM) was less declined in P. euphratica than in P. popularis, although the salt-induced transient kinetics were distinct from the drastic drop of O2 caused by hyperosmotic shock (255 mM mannitol). Short-term (ST) treatment (150 mM NaCl, 24 h) stimulated O2 influx in P. euphratica roots, and LT-treated P. euphratica displayed an increased O2 influx along the root axis, whereas O2 influx declined with increasing salinity in P. popularis roots. The spatial localization of O2 influxes revealed that the apical zone was more susceptible than the elongation region upon high NaCl (150, 200 mM) during ST and LT stress. Pharmacological experiments showed that the Na+ extrusion and H+-ATPase activity in salinized roots were correspondingly suppressed when O2 uptake was inhibited by a mitochondrial respiration inhibitor, NaN3. Therefore, we conclude that the stable mitochondrial respiration energized H+-ATPase of P. euphratica root cells for maintaining Na+ homeostasis under salt environments.


Assuntos
Populus , Adenosina Trifosfatases , Oxigênio , Raízes de Plantas , Cloreto de Sódio/farmacologia
9.
Int J Mol Sci ; 21(9)2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32397215

RESUMO

Water deficit caused by osmotic stress and drought limits crop yield and tree growth worldwide. Screening and identifying candidate genes from stress-resistant species are a genetic engineering strategy to increase drought resistance. In this study, an increased concentration of mannitol resulted in elevated expression of thioredoxin f (KcTrxf) in the nonsecretor mangrove species Kandelia candel. By means of amino acid sequence and phylogenetic analysis, the mangrove Trx was classified as an f-type thioredoxin. Subcellular localization showed that KcTrxf localizes to chloroplasts. Enzymatic activity characterization revealed that KcTrxf recombinant protein possesses the disulfide reductase function. KcTrxf overexpression contributes to osmotic and drought tolerance in tobacco in terms of fresh weight, root length, malondialdehyde (MDA) content, and hydrogen peroxide (H2O2) production. KcTrxf was shown to reduce the stomatal aperture by enhancing K+ efflux in guard cells, which increased the water-retaining capacity in leaves under drought conditions. Notably, the abscisic acid (ABA) sensitivity was increased in KcTrxf-transgenic tobacco, which benefits plants exposed to drought by reducing water loss by promoting stomatal closure. KcTrxf-transgenic plants limited drought-induced H2O2 in leaves, which could reduce lipid peroxidation and retain the membrane integrity. Additionally, glutathione (GSH) contributing to reactive oxygen species (ROS) scavenging and transgenic plants are more efficient at regenerating GSH from oxidized glutathione (GSSG) under conditions of drought stress. Notably, KcTrxf-transgenic plants had increased glucose and fructose contents under drought stress conditions, presumably resulting from KcTrxf-promoted starch degradation under water stress. We conclude that KcTrxf contributes to drought tolerance by increasing the water status, by enhancing osmotic adjustment, and by maintaining ROS homeostasis in transgene plants.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Tiorredoxinas de Cloroplastos/genética , Tiorredoxinas de Cloroplastos/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Nicotiana/metabolismo , Rhizophoraceae/química , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacologia , Sequência de Aminoácidos , Secas , Frutose/metabolismo , Glucose/metabolismo , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Manitol/toxicidade , NADH NADPH Oxirredutases/metabolismo , Pressão Osmótica , Filogenia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Estômatos de Plantas/citologia , Estômatos de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Análise de Sequência , Nicotiana/efeitos dos fármacos , Regulação para Cima , Água/metabolismo
10.
Chem Commun (Camb) ; 56(13): 1984-1987, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-31960842

RESUMO

Reversible single-crystal-to-single-crystal photocyclization-cycloreversion reaction of a stilbene-based coordination network exhibits a conspicuous fluorescence change. The controllable fluorescence and high fatigue resistance feature of this bistable material make it a single-crystalline device for applications in rewritable optical memory storage systems.

11.
Chem Asian J ; 14(20): 3635-3641, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31207177

RESUMO

The pure diolefinic ligand 1,4-bis(pyridin-4-yl)-1,3-butadiene (bpbde) is photostable in the crystalline state. With the assistance of coordination-driven metal-organic assemblies, the photoreactivity of this diolefinic ligand can be significantly enhanced. A hydrothermal reaction of bpbde with Cd(NO3 )2 ⋅4 H2 O and the auxiliary ligand adipic acid resulted in the formation of a two-dimensional photoreactive coordination polymer (CP), [Cd(adipate)(bpbde)]n (1). When the aliphatic carboxylic acid was replaced by pimelic acid, another photoreactive CP [Cd(pimelate)(bpbde)]n (2) with a three-dimensional framework was obtained. With irradiation of 365 nm UV light, the bpbde ligands in crystalline 1 and 2 underwent a regioselective photochemical [2+2] cycloaddition reaction and converted to 3,4,7,8-tetra(pyridin-4-yl)tricyclo[4.2.0.02,5 ]octane (tptco) and 1,3-bis(pyridin-4-yl)-2,4-bis(2-(pyridin-4-yl)vinyl)cyclobutane (bpbpvcb), respectively. The results provide an interesting insight into the rational design of highly regio- or stereoselective photocatalytic reactions for the formation of special organic molecules.

12.
Chem Commun (Camb) ; 54(46): 5831-5834, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29761180

RESUMO

Reversible cycloaddition reactions between 1,4-bis[2-(3-pyridyl)ethenyl]benzene and its photodimers were performed within a pair of three-dimensional coordination polymers with retention of single crystal character. In each case, switching between two crystalline forms could be followed by monitoring the flourescence behaviour.

13.
Inorg Chem ; 57(2): 849-856, 2018 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-29292993

RESUMO

The observation of a reversible chemical transformation corresponding to an external stimulus in the solid state is intriguing in the exploration of smart materials, which can potentially be applied in molecular machines, molecular switches, sensors, and data storage devices. The solid-state photodimerization reaction of 1,3-bis[2-(4-pyridyl)ethenyl]benzene (1,3-bpeb) in a one-dimensional coordination polymer {[Cd2(1,3-bpeb)2(4-FBA)4]·H2O}n (4-FBA = 4-fluorobenzoate) with 365 nm UV light afforded syn-tetrakis(4-pyridyl)-1,2,9,10-diethano[2.2]metacyclophane (syn-tpmcp) in quantitative yield via a single-crystal-to-single-crystal (SCSC) transformation. Upon irradiation with 254 nm UV light, an SCSC conversion from syn-tpmcp to 1,3-bpeb was also achieved in quantitative yield within the syn-tpmcp-supported coordination polymer {[Cd2(syn-tpmcp)(4-FBA)4]·H2O}n. In particular, accompanied by the reversible transformation between 1,3-bpeb and syn-tpmcp, the coordination chain exhibits photocontrollable fluorescence-switching behavior, which makes this intelligent material an appealing candidate for practical applications.

14.
Eur J Haematol ; 98(3): 198-217, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27893170

RESUMO

BACKGROUND: This review describes the safety of deferoxamine (DFO), deferiprone (DFP), deferasirox (DFX) and combined therapy in young patients less than 25 yr of age with haemoglobinopathies. METHODS: Searches in electronic literature databases were performed. Studies reporting adverse events associated with iron chelation therapy were included. Study and reporting quality was assessed using AHRQ Risk of Bias Assessment Tool and McMaster Quality Assessment Scale of Harms. Prospective clinical studies were pooled in a random-effects meta-analysis of proportions. RESULTS: Safety data of 2040 patients from 34 studies were included. Ninety-two case reports of 246 patients were identified. DFX (937 patients) and DFP (667 patients) possess the largest published safety evidence. Fewer studies on combination regimens are available. Increased transaminases were seen in all regimens (3.9-31.3%) and gastrointestinal disorders with DFP and DFX (3.7-18.4% and 5.8-18.8%, respectively). Therapy discontinuations due to adverse events were low (0-4.1%). Reporting quality was selective and poor in most of the studies. CONCLUSION: Iron chelation therapy is generally safe in young patients, and published data correspond to summary of product characteristics. Each iron chelation regimen has its specific safety risks. DFO seems not to be associated with serious adverse effects in recommended doses. In DFP and DFX, rare, but serious, adverse reactions can occur. Data on combined therapy are scarce, but it seems equally safe compared to monotherapy.


Assuntos
Hemoglobinopatias/complicações , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Terapia por Quelação , Quimioterapia Combinada , Hemoglobinopatias/terapia , Humanos , Quelantes de Ferro/administração & dosagem , Reação Transfusional
15.
Front Plant Sci ; 6: 23, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25657655

RESUMO

Na(+) uptake and transport in Kandelia candel and antioxidative defense were investigated under rising NaCl stress from 100 to 300 mM. Salinized K. candel roots had a net Na(+) efflux with a declined flux rate during an extended NaCl exposure. Na(+) buildup in leaves enhanced H2O2 levels, superoxide dismutase (SOD) activity, and increased transcription of CSD gene encoding a Cu/Zn SOD. Sequence and subcellular localization analyses have revealed that KcCSD is a typical Cu/Zn SOD in chloroplast. The transgenic tobacco experimental system was used as a functional genetics model to test the effect of KcCSD on salinity tolerance. KcCSD-transgenic lines were more Na(+) tolerant than wild-type (WT) tobacco in terms of lipid peroxidation, root growth, and survival rate. In the latter, 100 mM NaCl led to a remarkable reduction in chlorophyll content and a/b ratio, decreased maximal chlorophyll a fluorescence, and photochemical efficiency of photosystem II. NaCl stress in WT resulted from H2O2 burst in chloroplast. Na(+) injury to chloroplast was less pronounced in KcCSD-transgenic plants due to upregulated antioxidant defense. KcCSD-transgenic tobacco enhanced SOD activity by an increment in SOD isoenzymes under 100 mM NaCl stress from 24 h to 7 day. Catalase activity rose in KcCSD overexpressing tobacco plants. KcCSD-transgenic plants better scavenged NaCl-elicited reactive oxygen species (ROS) compared to WT ones. In conclusion, K. candel effectively excluded Na(+) in roots during a short exposure; and increased CSD expression to reduce ROS in chloroplast in a long-term and high saline environment.

16.
Tree Physiol ; 33(1): 81-95, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23264032

RESUMO

Using 3-month-old seedlings of Bruguiera gymnorrhiza (L.) Savigny and Kandelia candel (L.) Druce, we compared species differences in ionic homeostasis control between the two non-secretor mangrove species. A high salinity (400 mM NaCl, 4 weeks) resulted in a decline of the K(+)/Na(+) ratio in root and leaf tissues, and the reduction was more pronounced in K. candel (41-66%) as compared with B. gymnorrhiza (5-36%). Salt-altered flux profiles of Na(+), K(+), H(+) and Ca(2+) in roots and effects of exogenous hydrogen peroxide (H(2)O(2)), nitric oxide (NO) and Ca(2+) on root ion fluxes were examined in seedlings that were hydroponically treated short term with 100 mM NaCl (ST, 24 h) and long term with 200 mM NaCl (LT, 7 days). Short term and LT salinity resulted in Na(+) efflux and a correspondingly increased H(+) influx in roots of both species, although a more pronounced effect was observed in B. gymnorrhiza. The salt-enhanced exchange of Na(+) with H(+) was obviously inhibited by amiloride (a Na(+)/H(+) antiporter inhibitor) or sodium orthovanadate (a plasma membrane H(+)-ATPase inhibitor), indicating that the Na(+) efflux resulted from active Na(+) exclusion across the plasma membrane. Short term and LT salinity accelerated K(+) efflux in the two species, but K. candel exhibited a higher flux rate. The salt-induced K(+) efflux was markedly restricted by the K(+) channel blocker, tetraethylammonium chloride, indicating that the K(+) efflux is mediated by depolarization-activated channels, e.g., KORCs (outward rectifying K(+) channels) and NSCCs (non-selective cation channels). Exogenous H(2)O(2) application (10 mM) markedly increased the apparent Na(+) efflux and limited K(+) efflux in ST-treated roots, although H(2)O(2) caused a higher Na(+) efflux in B. gymnorrhiza roots. CaCl(2) (10 mM) reduced the efflux of K(+) in salinized roots of the two mangroves, but its enhancement of Na(+) efflux was found only in B. gymnorrhiza. Under ST treatment, sodium nitroprusside (SNP) (100 ∝M, an NO donor) increased Na(+) efflux at the root apex of the two species; however, its inhibition of K(+) loss was seen only in K. candel. Of note, NaCl caused an obvious influx of Ca(2+) in B. gymnorrhiza roots, which was enhanced by H(2)O(2) (10 mM). Therefore, the salt-induced Ca(2+) benefits B. gymnorrhiza in maintaining K(+)/Na(+) homeostasis under high external salinity.


Assuntos
Cálcio/metabolismo , Peróxido de Hidrogênio/metabolismo , Óxido Nítrico/metabolismo , Raízes de Plantas/metabolismo , Rhizophoraceae/metabolismo , Cloreto de Sódio/farmacologia , Raízes de Plantas/efeitos dos fármacos , Potássio/metabolismo , Rhizophoraceae/efeitos dos fármacos , Sódio/metabolismo
17.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 10): m1397, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22064763

RESUMO

In the title compound, {[Ni(C(10)H(8)N(2))(H(2)O)(4)](C(12)H(8)O(4))}(n), the Ni(II), 4,4'-bipyridyl (bipy) and 3,3'-(p-phenyl-ene)diacrylate (L(2-)) moieties are situated on inversion centres. The bipy ligands bridge Ni(II) ions into positively charged polymeric chains along [101]. The Ni(II) atom is coordinated by two N atoms from two bipy ligands and four water mol-ecules in a distorted octa-hedral geometry. L(2-) anions inter-act with the polymeric chains via O-H⋯O hydrogen bonds, forming a three-dimensional supra-molecular network.

18.
Dalton Trans ; 40(10): 2170-2, 2011 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-21060955

RESUMO

Photochemical single-crystal to single-crystal transformation of one 1D polymer [Cd(bpe)(CBA)(2)](n) afforded a new 1D polymer [Cd(rctt-tpcb)(0.5)(CBA)(2)](n) which underwent hydrothermal reaction in strong acidic solution to form a 3D coordination polymer {[Cd(rtct-tpcb)Cl(2)]·2H(2)O}(n).

19.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 11): m1540, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22219784

RESUMO

In the title compound, [Cd(C(10)H(8)O(4))(C(13)H(14)N(2))](n), two symmetry-related Cd atoms are bridged by two carboxyl-ate O atoms into a binuclear Cd(2) subunit around an inversion center. The Cd atom has a distorted penta-gonal-bipyramidal environment, defined by five O atoms from three different 1,3-phenylendiacetate (1,3-pda) ligands and two N atoms from two 1,3-di-4-pyridyl-propane (bpp) ligands. Each Cd(2) subunit is linked to four different Cd(2) subunits by four 1,3-pda ligands and four bpp ligands, forming a two-dimensional network with rhombic grids (12.50 × 12.50 Å(2)) extending along the ab plane.

20.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 11): m1553, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22219794

RESUMO

In the title coordination compound, {[Zn(C(7)H(4)BrO(2))(2)(C(12)H(10)N(2))]·CH(3)CN}(n), the Zn(II) atom is four-coordinated in a distorted tetra-hedral environment by two carboxyl-ate O atoms from two different 4-bromo-benzoate (bpe) ligands and two N atoms from two symmetry-related 1,2-bis-(4-pyrid-yl)ethene ligands. The Zn(II) atoms are bridged by the bpe ligands, which lie across centres of inversion, forming a zigzag chain along [001]. The void space of each unit cell is occupied by an acetonitrile solvent mol-ecule, which is connected to the complex mol-ecule by a weak C-H⋯N hydrogen bond.

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