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1.
Plant Physiol Biochem ; 210: 108616, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38615444

RESUMO

This study aims to examine the effect of foliar magnetic iron oxide (Fe3O4) nanoparticles (IONP) application on the physiology, photosynthetic parameters, magnetic character, and mineral element distribution of cherry tomatoes (Solanum lycopersicum var. cerasiforme). The IONP suspension (500 mg L-1) was sprayed once (S1), twice (S2), thrice (S3), and four times (S4) a week on seedlings. Upon 21 days of the treatments, photosynthetic parameters (chlorophyll, carotenoids, photosynthetic yield, electron transport rate) were elucidated. Inductively-coupled plasma-optical emission spectrometer (ICP-OES) and vibrating sample magnetometer (VSM) were used to determine the mineral elements and abundance of magnetic power in the seedlings. In addition, the RT-qPCR method was performed to quantify the expressions of photosystem-related (PsaC, PsbP6, and PsbQ) and ferritin-coding (Fer-1 and Fer-2) genes. Results revealed that the physiological and photosynthetic indices were improved upon S1 treatment. The optimal dosage of IONP spraying enhances chlorophyll, carotenoid, electron transport rate (ETR), and effective photochemical quantum yield of photosystem II (Y(II)) but substantially diminishes non-photochemical quenching (NPQ). However, frequent IONP applications (S2, S3, and S4) caused growth retardation and suppressed the photosynthetic parameters, suggesting a toxic effect of IONP in recurrent treatments. Fer-1 and Fer-2 expressions were strikingly increased by IONP applications, suggesting an attempt to neutralize the excess amount of Fe ions by ferritin. Nevertheless, frequent IONP treatment fluctuated the mineral distribution and caused growth inhibition. Although low-repeat foliar applications of IONP (S1 in this study) may help improve plant growth, consecutive applications (S2, S3, and S4) should be avoided.


Assuntos
Fotossíntese , Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/metabolismo , Fotossíntese/efeitos dos fármacos , Folhas de Planta/metabolismo , Folhas de Planta/efeitos dos fármacos , Nanopartículas Magnéticas de Óxido de Ferro , Clorofila/metabolismo , Minerais/metabolismo , Carotenoides/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Compostos Férricos
2.
Environ Sci Pollut Res Int ; 31(14): 22171-22186, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38403831

RESUMO

Root-to-shoot translocation of nanoparticles (NPs) is a matter of interest due to their possible unprecedented effects on biota. Properties of NPs, such as structure, surface charge or coating, and size, determine their uptake by cells. This study investigates the size effect of iron oxide (Fe3O4) NPs on plant uptake, translocation, and physiology. For this purpose, Fe3O4 NPs having about 10 and 100 nm in average sizes (namely NP10 and NP100) were hydroponically subjected to barley (Hordeum vulgare L.) in different doses (50, 100, and 200 mg/L) at germination (5 days) and seedling (3 weeks) stages. Results revealed that particle size does not significantly influence the seedlings' growth but improves germination. The iron content in root and leaf tissues gradually increased with increasing NP10 and NP100 concentrations, revealing their root-to-shoot translocation. This result was confirmed by vibrating sample magnetometry analysis, where the magnetic signals increased with increasing NP doses. The translocation of NPs enhanced chlorophyll and carotenoid contents, suggesting their contribution to plant pigmentation. On the other hand, catalase activity and H2O2 production were higher in NP10-treated roots compared to NP100-treated ones. Besides, confocal microscopy revealed that NP10 leads to cell membrane damages. These findings showed that Fe3O4 NPs were efficiently taken up by the roots and transported to the leaves regardless of the size factor. However, small-sized Fe3O4 NPs may be more reactive due to their size properties and may cause cell stress and membrane damage. This study may help us better understand the size effect of NPs in nanoparticle-plant interaction.


Assuntos
Hordeum , Hordeum/metabolismo , Tamanho da Partícula , Bioacumulação , Peróxido de Hidrogênio/metabolismo , Plântula , Nanopartículas Magnéticas de Óxido de Ferro
3.
3 Biotech ; 13(9): 296, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37564274

RESUMO

The effect and contribution of an external magnetic field (MF) on the uptake and translocation of nanoparticles (NPs) in plants have been investigated in this study. Barley was treated with iron oxide NPs (Fe3O4, 500 mg/L, 50-100 nm) and grown under various MF strengths (20, 42, 125, and 250 mT). The root-to-shoot translocation of NPs was assessed using a vibrating sample magnetometer (VSM) and inductively coupled plasma optical emission spectrometry (ICP-OES). Additionally, plant phenological parameters, such as germination, protein and chlorophyll content, and photosynthetic and nutritional status, were examined. The results demonstrated that the external MF significantly enhances the uptake of NPs through the roots. The uptake was higher at lower MF strengths (20 and 42 mT) than at higher MF strengths (125 and 250 mT). The root and shoot iron (Fe) contents were approximately 2.5-3-fold higher in the 250 mT application compared to the control. Furthermore, the MF treatments significantly increased micro-elements such as Mn, Zn, Cu, Mo, and B (P < 0.005). This effect could be attributed to the disruption of cell membranes at the root tip cells caused by both the MF and NPs. Moreover, the MF treatments improved germination rates by 28%, total protein content, and photosynthetic parameters. These findings show that magnetic field application helps the effective transport of magnetic NPs, which could be essential for NPs-mediated drug delivery, plant nutrition, and genetic transformation applications. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03727-4.

4.
ACS Omega ; 8(9): 8303-8319, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36910964

RESUMO

To evaluate the potential role of in situ formed Sr-Ti-O species as a ferroelectric component able to enhance the photocatalytic properties of an adjacent TiO2 semiconductor, Cu-doped/graphene oxide (GO)/TiO2 nanotubes (TiNTs) composites (with 0.5 wt % Cu and 1.0 wt % GO) have been synthesized while progressive amounts of strontium (up to 1.0 wt %) were incorporated at the surface of the composite through incipient wetness impregnation followed by post-thermal treatment at 400 °C. The different resulting photocatalytic systems were then first deeply characterized by means of N2 adsorption-desorption measurements, X-ray diffraction (XRD), UV-vis diffuse reflectance (UV-vis DR), Raman and photoluminescence (PL) spectroscopies, and scanning electron microscopy (SEM) (with energy-dispersive X-ray (EDX) spectroscopy and Z-mapping). In a second step, optimization of the kinetic response of the Sr-containing composites was performed for the formic acid photodegradation under UV irradiation. The Sr-containing Cu/GO/TiNT composites were then fully characterized by electrochemical impedance spectroscopy (EIS) for their dielectric properties showing clearly the implication of polarization induced by the Sr addition onto the stabilization of photogenerated charges. Finally, a perfect correlation between the photocatalytic kinetic evaluation and dielectric properties undoubtedly emphasizes the role of ferroelectric polarization as a very valuable approach to enhance the photocatalytic properties in an adjacent semiconductor.

5.
Plant Physiol Biochem ; 170: 36-48, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34844116

RESUMO

The magnetic field (MF) interacts with biological systems and has the potential to increase germination, plant growth and productivity. Although it is known as a low cost and promising approach, the mechanism that increases growth is not fully understood yet. In this study, the effect of different MF strengths (20, 42, 125, and 250 mT) was investigated on barley (Hordeum vulgare L.). In addition to phenological parameters, possible cell damage, electron transport rate, chlorophyll fluorescence, magnetic character and elemental status of tissues were determined. Results showed that lower strengths (≤125 mT) of MF treatment improve germination. Confocal microscopy analyzes revealed MF-induced cell membrane damage in roots that could alter the elemental content of tissues. Elemental analyzes found that the content of macroelements (Ca, Mg, P, and K) are gradually reduced with increasing MF forces; in opposite the microelement contents (Fe, B, Cu, Mn, Zn, and Mo) are increased in roots. Diamagnetism is the dominant magnetic character in all root and leaf samples. However, the roots became surprisingly superparamagnetic in 250 mT application. It seems that MF treatment at higher strength (250 mT in this study) could influence the orientation of magnetic moments. These findings suggest that MF application: i) can alter the magnetic character of plants, ii) enhances the germination, photosynthetic machinery, and growth, and iii) affects the nutrient uptake and abundance in tissues, depending on the MF strength. This comprehensive study can help in understanding the interaction of magnetic field with plants.


Assuntos
Hordeum , Clorofila , Fluorescência , Germinação , Campos Magnéticos , Nutrientes , Raízes de Plantas
6.
Environ Sci Pollut Res Int ; 29(3): 4710-4721, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34414536

RESUMO

The increasing demand for food in the world has made sustainable agriculture practices even more important. Nanotechnology applications in many areas have also been used in sustainable agriculture in recent years for the purposes to improve plant yield, pest control, etc. However, ecotoxicology and environmental safety of nanoparticles must be evaluated before large-scale applications. This study comparatively explores the efficacy and fate of different iron oxide NPs (γ-Fe2O3-maghemite and Fe3O4-magnetite) on barley (Hordeum vulgare L.). Various NP doses (50, 100, and 200 mg/L) were applied to the seeds in hydroponic medium for 3 weeks. Results revealed that γ-Fe2O3 and Fe3O4 NPs significantly improved the germination rate (~37% for γ-Fe2O3; ~63% for Fe3O4), plant biomass, and pigmentation (P < 0.005). Compared to the control, the iron content of tissues gradually raised by the increasing NPs doses revealing their translocation, which is confirmed by VSM analysis as well. The findings suggest that γ-Fe2O3 and Fe3O4 NPs have great potential to improve barley growth. They can be recommended for breeding programs as nanofertilizers. However, special care should be paid before the application due to their unknown effects on other living beings.


Assuntos
Hordeum , Nanopartículas de Magnetita , Nanopartículas , Compostos Férricos , Óxido Ferroso-Férrico , Raízes de Plantas
7.
Chemosphere ; 265: 129138, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33279234

RESUMO

Cobalt ferrite nanoparticles (CoFe2O4 NPs) have received increasing attention in a widespread application. This work examines the fate and impact of terbium (Tb) substituted CoFe2O4 NPs on the growth, physiological indices, and magnetic character of barley (Hordeum vulgare L.). Sonochemically synthesized NPs were hydroponically applied on barley with changing doses (125-1000 mg/L) at germination and seedling (three weeks) stages. Results revealed a significant reduction in germination rate (∼37% at 1000 mg/L); however, a remarkable growth (∼38-65%) and biomass (∼72-133%) increase were detected at three weeks of exposure (p < 0.05). The elements that make up the NPs (i.e., Tb, Co, and Fe) increased significantly in both root and leaf tissues, indicating the translocation of NPs from the root to leaf. Vibrating-sample magnetometer (VSM) analysis confirmed this finding, where magnetic signals in the root and leaf samples of the control were respectively about 26 and 75 times lower than that of NPs-treated tissues. Also, the accumulation of NPs altered the leaf photoluminescence (PL) behavior, which may have contributed to the biomass increase. Overall, Tb-doped CoFe2O4 NPs translocate from root-to-leaf and enhance plant growth, possibly due to i) incorporation of iron within tissues, and ii) changes in photoluminescence. However, since its effects on other living things are not known yet, its agricultural use and release to nature should be considered well.


Assuntos
Hordeum , Nanopartículas , Cobalto , Compostos Férricos , Raízes de Plantas
8.
Nanomaterials (Basel) ; 10(12)2020 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-33260444

RESUMO

Tm-Tb co-substituted Co-Ni nanospinel ferrites (NSFs) as (Co0.5Ni0.5) [TmxTbxFe2-2x]O4 (x = 0.00-0.05) NSFs were attained via the ultrasound irradiation technique. The phase identification and morphologies of the NSFs were explored using X-rays diffraction (XRD), selected area electron diffraction (SAED), and transmission and scanning electronic microscopes (TEM and SEM). The magnetization measurements against the applied magnetic field (M-H) were made at 300 and 10 K with a vibrating sample magnetometer (VSM). The various prepared nanoparticles revealed a ferrimagnetic character at both 300 and 10 K. The saturation magnetization (Ms), the remanence (Mr), and magneton number (nB) were found to decrease upon the Tb-Tm substitution effect. On the other hand, the coercivity (Hc) was found to diminish with increasing x up to 0.03 and then begins to increase with further rising Tb-Tm content. The Hc values are in the range of 346.7-441.7 Oe at 300 K to 4044.4-5378.7 Oe at 10 K. The variations in magnetic parameters were described based on redistribution of cations, crystallites and/or grains size, canting effects, surface spins effects, super-exchange interaction strength, etc. The observed magnetic results indicated that the synthesized (Co0.5Ni0.5)[TmxTbxFe2-x]O4 NSFs could be considered as promising candidates to be used for room temperature magnetic applications and magnetic recording media.

9.
Environ Pollut ; 266(Pt 1): 115391, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32823044

RESUMO

There has been a growing concern with the environmental influences of nanomaterials due to recent developments in nanotechnology. This study investigates the impact and fate of hematite nanoparticles (α-Fe2O3 NPs) (∼14 nm in size) on a crop species, barley (Hordeum vulgare L.). For this purpose, hematite NPs (50, 100, 200, and 400 mg/L) were hydroponically applied to barley at germination and seedling stages (three weeks). Inductively coupled plasma mass spectrophotometry (ICP-MS) along with vibrating sample magnetometer (VSM) techniques were used to track the NPs in plant tissues. The effects of NPs on the root cells were observed by scanning electron microscopy (SEM) and confocal microscopy. Results revealed that α-Fe2O3 NPs significantly reduced the germination rate (from 80% in control to 30% in 400 mg/L), as well as chlorophyll (36-39%) and carotenoid (37%) contents. Moreover, the treatment led to a significant decline in the quantum yield of photosystem II (Fv/Fm). Leaf VSM analysis indicated a change in magnetic signal for NPs-treated samples compared with untreated ones, which is mostly attributed to the iron (Fe) ions incorporated within the leaf tissue. Besides, Fe content in the roots and leaf had gradually increased by the increasing doses of NPs, which was confirming NPs' translocation to the aerial parts. Microscopic observations revealed that α-Fe2O3 NPs altered root cell morphology and led to the injury of cell membranes. This study, in the light of our findings, shows that α-Fe2O3 NPs (∼14 nm in size) are taken up by the roots of the barley plants, and migrate to the plant leaves. Besides, NPs are phytotoxic for barley as they inhibit germination and pigment biosynthesis. This inhibition is probably due to the injury of the cell membranes in the roots. Therefore, the use of hematite NPs in agriculture and thereby their environmental diffusion must be addressed carefully.


Assuntos
Hordeum , Nanopartículas , Compostos Férricos , Raízes de Plantas
10.
Ecotoxicol Environ Saf ; 194: 110377, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32145527

RESUMO

Nanomaterials (NMs) have emerged in the last decades and are used in many disciplines such as industry, material sciences, biomedicine, biotechnology, bioenergy, and agriculture. The size of the NMs is a critical factor that affects NMs' integration and transfer into the biological systems. Therefore, this study aims at investigating the effect of NMs-size on i) plant growth and physiology, and ii) NMs uptake and translocation in plant tissues. For these purposes, iron (III) oxide (Fe2O3) NMs with varied sizes, 8-10, 20-40, and 30-50 nm, have been applied to wheat plants in a hydroponic system. Results showed that Fe2O3 NMs enhanced root length, plant height, biomass, and chlorophyll content of wheat. Confocal microscopy analysis indicated that Fe2O3 NMs cause injury in root-tip cells without a visible toxic symptom. Vibrating sample magnetometer (VSM), and inductively coupled plasma-mass spectroscopy (ICP-MS) analyses of leaf tissues revealed that all tested NMs were up taken by wheat plant and translocated to the leaves. Iron content was found to be dramatically increased in NMs-treated plant tissues, which possibly contributed to the growth enhancement. Experiments confirmed that Fe2O3 NMs with 20-40 nm size is much more efficient in plant growth compared to those with 8-10 and 30-50 nm size. Overall, Fe2O3 NMs with 20-40 nm in size could be proposed as a nano-fertilizer for agricultural applications. On the other hand, the translocation of NMs in the wheat plant requires further investigation of their effects on the end users.


Assuntos
Fertilizantes , Nanopartículas/toxicidade , Desenvolvimento Vegetal/efeitos dos fármacos , Triticum/efeitos dos fármacos , Transporte Biológico , Biomassa , Clorofila/metabolismo , Compostos Férricos/química , Compostos Férricos/farmacologia , Hidroponia , Nanopartículas/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
11.
Ecotoxicol Environ Saf ; 186: 109751, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31600650

RESUMO

In this study, calcium and magnesium substituted strontium nano-hexaferrites (Sr0.96Mg0.02Ca0.02Fe12O19, SrMgCa nano-HF) were synthesized by the sol-gel auto-combustion method and their impact on the nutrient uptake, magnetic character and physiology of barley (Hordeum vulgare L.), a crop plant, was investigated. Structural, microstructural, and magnetic properties of nano-HF were evaluated by using vibrating sample magnetometry (VSM), X-ray diffraction (XRD), scanning electron microscopy (SEM) along with energy-dispersive X-ray (EDX) and elemental mapping techniques. Plants were hydroponically exposed to nano-HF (ranging from 125 to 1000 mg/L) for three weeks. Results showed that the SrMgCa nano-HF application enhanced germination rate (about 20%), tissue growth (about 38%), biomass (about 20%), soluble protein content (about 41%), and chlorophyll pigments (about 33-42%) when compared to the untreated control. In general, the plants showed the highest growth achievement at 125 or 250 mg/L of nano-HF treatment. However, higher doses diminished the growth parameters. Element concentrations and magnetic behavior analyses of plant parts proved that SrMgCa nano-HF with a size of 42.4 nm are up-taken by the plant roots and lead to increase in iron, calcium, magnesium, and strontium contents of leaves, which were about 20, 18, 3, and 60 times higher in 500 mg/L nano-HF-treated leaves than those of control, respectively. Overall, this study shows for the first time that the four elements have been internalized into the plant body through the application of substituted nano-HF. These findings suggest that mineral-substituted nanoparticles can be incorporated into plant breeding programs for the i) enhancement of seed germination and ii) treatment of plants by fighting with mineral deficiencies.


Assuntos
Cálcio/farmacologia , Compostos Férricos/farmacologia , Hordeum/efeitos dos fármacos , Magnésio/farmacologia , Fenômenos Magnéticos , Nanopartículas , Estrôncio/farmacologia , Transporte Biológico , Biomassa , Cálcio/metabolismo , Clorofila/metabolismo , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Produtos Agrícolas/fisiologia , Compostos Férricos/metabolismo , Germinação/efeitos dos fármacos , Hordeum/crescimento & desenvolvimento , Hordeum/metabolismo , Hidroponia , Ferro/metabolismo , Ferro/farmacologia , Magnésio/metabolismo , Minerais/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Estrôncio/metabolismo
12.
Plant Physiol Biochem ; 139: 56-65, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30878838

RESUMO

This study investigates the effect of SPIONs (superparamagnetic iron oxide nanoparticles, ∼12.5 nm in size) on summer squash plant (Cucurbita pepo) in the presence and absence of supplementary iron (Fe(II)-EDTA). The plants were grown in nutrient solution with different iron sources: (i) Fe(II)-EDTA, (ii) without Fe(II)-EDTA (iii) SPIONs only, and (iv) Fe(II)-EDTA with SPIONs. Plant growth and development were assessed after 20 days of soaking by measuring phenological parameters such as plant biomass, chlorophyll content, amount of carotenoids, and the catalase enzyme activity. Transmission electron microscopy, inductively coupled plasma atomic emission spectroscopy, X-ray diffraction, and vibrating sample magnetometer methods were used to detect uptake and translocation of SPIONs in plant tissues. Our results showed that SPIONs treatment (without Fe(II)-EDTA) caused growth retardation and decreased the plant biomass and chlorophyll content. Hence, they are not efficient sources to compensate for iron demand of squash plant. Electron microscopy observations, magnetization and elemental analyses revealed that SPIONs are taken-up by plant roots but not translocate to upper organs. In roots, SPIONs use a symplastic route for intercellular transfer. These findings suggest that as an iron source, SPIONs alone are not efficient for plant growth, but can contribute it together with Fe(II)-EDTA.


Assuntos
Cucurbita/efeitos dos fármacos , Ácido Edético/farmacologia , Compostos Ferrosos/farmacologia , Nanopartículas de Magnetita , Carotenoides/metabolismo , Catalase/metabolismo , Clorofila/metabolismo , Cucurbita/crescimento & desenvolvimento , Cucurbita/fisiologia , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo
13.
Nanomaterials (Basel) ; 9(3)2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30871266

RESUMO

Co0.5Ni0.5NbxFe2-xO4 (0.00 ≤ x ≤ 0.10) nanoparticles (NPs) were prepared using the hydrothermal approach. The X-ray powder diffraction (XRD) pattern confirmed the formation of single-phase spinel ferrite. The crystallite size was found to range from 18 to 26 nm. The lattice parameters were found to increase with greater Niobium ion (Nb3+) concentration, caused by the variance in the ionic radii between the Nb3+ and Fe3+. Fourier transform infrared analysis also proved the existence of the spinal ferrite phase. The percent diffuse reflectance (%DR) analysis showed that the value of the band gap increased with growing Nb3+ content. Scanning electron microscopy and transmission electron microscopy revealed the cubic morphology. The magnetization analyses at both room (300 K, RT) and low (10 K) temperatures exhibited their ferromagnetic nature. The results showed that the Nb3+ substitution affected the magnetization data. We found that Saturation magnetization (Ms), Remanence (Mr), and the Magnetic moment ( n B ) decreased with increasing Nb3+. The squareness ratio (SQR) values at RT were found to be smaller than 0.5, which postulate a single domain nature with uniaxial anisotropy for all produced ferrites. However, different samples exhibited SQRs within 0.70 to 0.85 at 10 K, which suggests a magnetic multi-domain with cubic anisotropy at a low temperature. The obtained magnetic results were investigated in detail in relation to the structural and microstructural properties.

14.
Environ Pollut ; 243(Pt B): 872-881, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30245449

RESUMO

The main objective of this study was to assess the uptake and translocation of MnFe2O4 magnetic nanoparticles (MNPs) in hydroponically grown barley (Hordeum vulgare L.). Hydrothermally synthesized and well characterized MNPs (average crystallite size of 14.5 ±â€¯0.5 nm) with varied doses (62.5, 125, 250, 500, and 1000 mg L-1) were subjected to the plants at germination and early growing stages (three weeks). The tissues analyzed by vibrating-sample magnetometer (VSM) and transmission electron microscopy (TEM) revealed the uptake and translocation of MNPs, as well as their internalization in the leaf cells. Also, elemental analysis proved that manganese (Mn) and iron (Fe) contents were ∼7-9 times and ∼4-7 times higher in the leaves of MNPs-treated plants than the ones for non-treated control, respectively. 250 mg L-1 of MNPs significantly (at least p < 0.05) promoted the fresh weight (FW, %10.25). However, higher concentrations (500 and 1000 mg L-1) remarkably reduced the increase to %8 and %5, respectively, possibly due to the restricted water uptake. Also, catalase activity was increased from 91 (µM H2O2 min-1 mg-1) to 138 in leaves, and decreased to 66 in roots upon 1000 mg L-1 of MNPs application. Chlorophyll and carotenoid contents were not significantly changed, except chlorophyll a (%6 increase at 1000 mg L-1, p < 0.05). Overall, MnFe2O4 NPs were up-taken from the roots and migrated to the leaves which promoted the growth parameters of barley. Hence, MNPs can be suggested for barley breeding programs and can be proposed as effective delivery system for agrochemicals. However, the possible negative effect of MNPs due to its potential horizontal transfer from plants to animals via the food chain must be also considered.


Assuntos
Compostos Férricos/toxicidade , Hordeum/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Clorofila/análise , Ativação Enzimática/efeitos dos fármacos , Germinação/efeitos dos fármacos , Hordeum/enzimologia , Hordeum/ultraestrutura , Hidroponia , Magnetismo , Compostos de Manganês , Microscopia Eletrônica de Transmissão , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/ultraestrutura , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/ultraestrutura
15.
Transfus Apher Sci ; 45(2): 157-60, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21855414

RESUMO

The patient, who was being followed up for Mantle Cell Lymphoma, was diagnosed with Mast Cell Leukemia 2 years after receiving R-CHOP treatment. The results of flow cytometry, which was performed upon determining leucocytosis and detecting blasts in the peripheral smear following the patient's presentation due to his poor general condition, was consistent with Mantle Cell Leukemia. This case is being presented since there are a very limited number of previously published cases on this topic.


Assuntos
Linfoma de Célula do Manto/diagnóstico , Linfoma de Célula do Manto/patologia , Humanos , Linfoma de Célula do Manto/terapia , Masculino , Pessoa de Meia-Idade
16.
Acta Crystallogr C ; 58(Pt 2): m137-8, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11828106

RESUMO

A new tetranuclear Cu(II)-Hg(II)-Hg(II)-Cu(II) complex, [Cu(2)Hg(2)Cl(4)(C(18)H(18)N(2)O(2))(2)], has been prepared by means of a copper complex found in the literature. The molecular structure of this complex was determined by X-ray diffraction and the Cu-Hg-Hg-Cu chain was seen to be non-linear. The change in magnetic susceptibility with temperature was recorded for this complex and observed to abide by the Curie-Weiss law. The coordination around the Hg(II) ions is square pyramidal. The Cu...Hg bridging distance is 3.5269(7)A.

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