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1.
Nature ; 607(7919): 480-485, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35859196

RESUMO

Pyroelectricity describes the generation of electricity by temporal temperature change in polar materials1-3. When free-standing pyroelectric materials approach the 2D crystalline limit, how pyroelectricity behaves remained largely unknown. Here, using three model pyroelectric materials whose bonding characters along the out-of-plane direction vary from van der Waals (In2Se3), quasi-van der Waals (CsBiNb2O7) to ionic/covalent (ZnO), we experimentally show the dimensionality effect on pyroelectricity and the relation between lattice dynamics and pyroelectricity. We find that, for all three materials, when the thickness of free-standing sheets becomes small, their pyroelectric coefficients increase rapidly. We show that the material with chemical bonds along the out-of-plane direction exhibits the greatest dimensionality effect. Experimental observations evidence the possible influence of changed phonon dynamics in crystals with reduced thickness on their pyroelectricity. Our findings should stimulate fundamental study on pyroelectricity in ultra-thin materials and inspire technological development for potential pyroelectric applications in thermal imaging and energy harvesting.

2.
Opt Express ; 32(11): 18441-18452, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38858999

RESUMO

Imaging the complex dynamics of micro-vibrations plays a fundamental role in the investigation of microelectromechanical systems (MEMS). However, it remains a challenge for achieving both a wide bandwidth and a low noise due to the high photodetector noise and electromagnetic interference at GHz frequencies. Here, we propose a pulsed laser interferometry system with an adaptable switch to image GHz vibrations based on stroboscopic mixing, while measuring lower-frequency vibrations based on the homodyne scheme. The noise power spectral density is shown in both regions from DC to 10 GHz with an average noise down to 30.8 fm/√Hz at GHz frequencies, which holds the highest resolution to the best of our knowledge. Vibrational amplitude and phase mappings of a kHz comb-drive resonator, a GHz piezoelectric transducer, and a GHz film bulk acoustic resonator are presented with animated visualizations and k-space analysis, paving a new paradigm for the first time to image and analyze various MEMS devices of a bandwidth spanning 10 orders of magnitude.

3.
Biochem Genet ; 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38379038

RESUMO

Propofol has been found to have a protective effect against spinal cord injury (SCI). However, the underlying molecular mechanism of propofol regulating SCI process remains unclear. In this study, lipopolysaccharide (LPS)-induced PC12 cells were used to build SCI cell models. Cell viability and apoptosis were determined by cell counting kit 8 assay, flow cytometry, and caspase-3 activity detection. The protein levels of apoptosis-related markers and TNFAIP3 interacting protein 2 (TNIP2) were assessed using western blot analysis, and the levels of inflammatory factors were detected using ELISA. Cell oxidative stress was evaluated by measuring malondialdehyde (MDA) and reactive oxygen species (ROS) levels. The expression of microRNA (miR)-672-3p was examined by quantitative real-time PCR. SCI rat models were constructed to assess the effect of propofol in vivo. We found that propofol treatment promoted viability, while inhibited apoptosis, inflammation and oxidative stress of LPS-induced PC12 cells. Propofol decreased miR-672-3p expression, and miR-672-3p overexpression eliminated the inhibiting effect of propofol on LPS-induced PC12 cell injury. Besides, miR-672-3p targeted TNIP2, and TNIP2 knockdown reversed the protective effect of miR-672-3p inhibitor or propofol against LPS-induced PC12 cell injury. In vivo experiments, propofol treatment enhanced the motor function recovery and inhibited apoptosis of SCI rat models. In conclusion, propofol increased TNIP2 level by reducing miR-672-3p expression, thereby alleviating LPS-induced PC12 cell injury and improving the motor function of SCI rat models.

4.
Sensors (Basel) ; 24(9)2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38733044

RESUMO

Film bulk acoustic-wave resonators (FBARs) are widely utilized in the field of radio frequency (RF) filters due to their excellent performance, such as high operation frequency and high quality. In this paper, we present the design, fabrication, and characterization of an FBAR filter for the 3.0 GHz-3.2 GHz S-band. Using a scandium-doped aluminum nitride (Sc0.2Al0.8N) film, the filter is designed through a combined acoustic-electromagnetic simulation method, and the FBAR and filter are fabricated using an eight-step lithographic process. The measured FBAR presents an effective electromechanical coupling coefficient (keff2) value up to 13.3%, and the measured filter demonstrates a -3 dB bandwidth of 115 MHz (from 3.013 GHz to 3.128 GHz), a low insertion loss of -2.4 dB, and good out-of-band rejection of -30 dB. The measured 1 dB compression point of the fabricated filter is 30.5 dBm, and the first series resonator burns out first as the input power increases. This work paves the way for research on high-power RF filters in mobile communication.

5.
Plant Cell Physiol ; 63(9): 1273-1284, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35859341

RESUMO

Although most cultivated soils have high levels of total phosphorus (P), the levels of bioavailable inorganic P (Pi) are insufficient. The application of plant-growth-promoting rhizobacteria (PGPR) is an eco-friendly strategy for P utilization; however, PGPR-mediated plant responses that enhance Pi acquisition remain unexplored. Here, we investigated the effect of Azospirillum brasilense on Arabidopsis adaptation to Pi deficiency. Results showed that A. brasilense inoculation alleviated Pi-deficiency-induced growth inhibition and anthocyanin accumulation and increased the total P content in Arabidopsis plants. A comprehensive analysis of root morphology revealed that A. brasilense increased root hair density and length under Pi-limited conditions. We further demonstrated that A. brasilense enhanced the acid phosphatase activity and upregulated the expression of several Pi transporter genes, such as PHOSPHATE1 (PHO1), PHOSPHATE TRANSPORTER 1:(PHT1:1) and PHT1;4. However, A. brasilense did not enhance the growth o total P content in pht1;1, pht1;4 and pht1;1pht1;4 mutants. Moreover, A. brasilense could not increase the P content and PHT1;1 expression in the root hairless mutant rsl4rsl2, because of the occurrence of low-Pi-induced PHT1;1 and PHT1;4 in root hairs. These results indicate that A. brasilense can promote root hair development and enhance acid phosphatase activity and Pi transporter expression levels, consequently improving the Pi absorption capacity and conferring plant tolerance to Pi deficiency.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Azospirillum brasilense , Fosfatase Ácida/genética , Fosfatase Ácida/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Azospirillum brasilense/metabolismo , Fosfatos/metabolismo , Fósforo/metabolismo , Raízes de Plantas/metabolismo
6.
J Exp Bot ; 73(17): 5903-5917, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-35767844

RESUMO

Plant mineral nutrition is critical for agricultural productivity and for human nutrition; however, the availability of mineral elements is spatially and temporally heterogeneous in many ecosystems and agricultural landscapes. Nutrient imbalances trigger intricate signalling networks that modulate plant acclimation responses. One signalling agent of particular importance in such networks is phytomelatonin, a pleiotropic molecule with multiple functions. Evidence indicates that deficiencies or excesses of nutrients generally increase phytomelatonin levels in certain tissues, and it is increasingly thought to participate in the regulation of plant mineral nutrition. Alterations in endogenous phytomelatonin levels can protect plants from oxidative stress, influence root architecture, and influence nutrient uptake and efficiency of use through transcriptional and post-transcriptional regulation; such changes optimize mineral nutrient acquisition and ion homeostasis inside plant cells and thereby help to promote growth. This review summarizes current knowledge on the regulation of plant mineral nutrition by melatonin and highlights how endogenous phytomelatonin alters plant responses to specific mineral elements. In addition, we comprehensively discuss how melatonin influences uptake and transport under conditions of nutrient shortage.


Assuntos
Melatonina , Ecossistema , Humanos , Minerais , Nutrientes , Raízes de Plantas , Plantas
7.
Sensors (Basel) ; 22(15)2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35957469

RESUMO

The development of MEMS acoustic resonators meets the increasing demand for in situ detection with a higher performance and smaller size. In this paper, a lithium niobate film-based S1 mode Lamb wave resonator (HF-LWR) for high-sensitivity gravimetric biosensing is proposed. The fabricated resonators, based on a 400-nm X-cut lithium niobate film, showed a resonance frequency over 8 GHz. Moreover, a PMMA layer was used as the mass-sensing layer, to study the performance of the biosensors based on HF-LWRs. Through optimizing the thickness of the lithium niobate film and the electrode configuration, the mass sensitivity of the biosensor could reach up to 74,000 Hz/(ng/cm2), and the maximum value of figure of merit (FOM) was 5.52 × 107, which shows great potential for pushing the performance boundaries of gravimetric-sensitive acoustic biosensors.


Assuntos
Acústica , Técnicas Biossensoriais , Eletrodos , Desenho de Equipamento , Vibração
8.
Zhonghua Nan Ke Xue ; 28(1): 9-13, 2022 Jan.
Artigo em Zh | MEDLINE | ID: mdl-37459071

RESUMO

Objective: To study the inhibitory effect of berberine hydrochloride (BBR) on BPH and its underlying mechanism in male rats. METHODS: Forty male rats were randomly divided into a normal control, a BPH model control, a BBR intervention, and a BBR+Bruceol intervention group, and the BPH model was established in the latter three groups. The animals in the normal and BPH model control groups were treated intragastrically with normal saline, and those in the BBR and BBR+Bruceol intervention groups with BBR at 200 mg/kg and BBR plus Bruceol at 1 mg/kg, respectively, once a day for 14 consecutive days. The prostates of the rats were harvested for measurement of their wet weight and prostatic index, detection of the contents of superoxide dismutase (SOD) and malondialdehyde (MDA) and determination of the protein expressions of nuclear factor E2-related factor 2 (Nrf2), antioxidant response element (ARE) and reduced coenzyme I quinone oxidoreductase (NQO1) in the prostate tissue by Western blot. RESULTS: The wet weights of the prostate in the normal control, BPH model control, BBR intervention, and BBR+Bruceol intervention groups were (715.63 ± 28.57) mg, (1118.93 ± 36.41) mg, (896.21 ± 20.24) mg and (967.23 ± 24.98) mg, the prostate indexes were 2.10 ± 0.13, 3.45 ± 0.22, 2.75 ± 0.19 and 3.01 ± 0.14, the SOD contents in the prostate tissue were (38.54 ± 5.12) U/mg, (13.98 ± 2.01) U/mg, (26.75 ± 3.19) U/mg and (20.16 ± 4.10) U/mg, and the MDA contents were (3.59 ± 0.83) nmol/mg, (12.63 ± 3.26) nmol/mg, (7.20 ± 1.69) nmol/mg and (9.85 ± 1.71) nmol/mg, respectively. The relative expressions of the Nrf2 protein in the four groups were 0.53 ± 0.06, 0.12 ± 0.03, 0.36 ± 0.04 and 0.25 ± 0.03, those of the ARE protein were 0.69 ± 0.07, 0.21 ± 0.02, 0.50 ± 0.06 and 0.30 ± 0.04, and those of the NQO1 protein were 0.44 ± 0.05, 0.15 ± 0.03, 0.30 ± 0.04 and 0.22 ± 0.03, respectively. There were statistically significant differences in all the above indicators between the normal and BPH model control groups (P < 0.05), as well as between the BPH model control and BBR intervention groups (P < 0.05) and between the BPH model control and the BBR+Bruceol intervention groups (P < 0.05). CONCLUSIONS: BBR hydrochloride can inhibit prostatic hyperplasia in BPH rats and reduce oxidative stress and pathological changes by activating the Nrf2/ARE pathway.

9.
Sensors (Basel) ; 21(2)2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33440659

RESUMO

Microelectromechanical (MEMS) piezoelectric accelerometers are diversely used in consumer electronics and handheld devices due to their low power consumption as well as simple reading circuit and good dynamic performance. In this paper, a tri-axial piezoelectric accelerometer with folded beams is presented. The four beam suspensions are located at two sides of the mass aligned with edges of the mass, and the thickness of the beams is the same as the thickness of the mass block. In order to realize the multi-axis detection, a total of 16 sensing elements are distributed at the end of the folded beams. The structural deformations, stress distribution, and output characteristics due to the acceleration in x-, y-, and z-axis directions are theoretically analyzed and simulated. The proposed accelerometer is fabricated by MEMS processes to form Mo/AlN/ScAlN/Mo piezoelectric stacks as the sensing layer. Experiments show that the charge sensitivity along the x-, y-, and z-axes could reach up to ~1.07 pC/g, ~0.66 pC/g, and ~3.35 pC/g. The new structure can provide inspiration for the design of tri-axial piezoelectric accelerometers with great sensitivity and linearity.

10.
Sensors (Basel) ; 21(19)2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34640734

RESUMO

In this paper, a novel ring-down suppression system based on transfer function is proposed for the first time to suppress the ring-down time and decrease the blind area of PMUTs (Piezoelectric Micromachined Ultrasonic Transducers). This suppression system includes a transfer function and a simple P (proportion) controller, which can reduce the ring-down time without degrading any performances of PMUTs. The transfer function serves as a virtual PMUT device, feeding its output into the P controller; then, the P controller generates a suppression signal to the actual PMUT device. The ring-down time of a 115-kHz PMUT array is demonstrated to be reduced by up to 93% through the suppression system. In addition, the P controller has been experimentally optimized, reducing the blind area of the PMUT array by about 40%. Moreover, a low ring-down PMUTs system design guideline is established, which is practical and straightforward for industrial scenarios. Finally, the system can be easily integrated into ASIC (Application Specific Integrated Circuit).


Assuntos
Sistemas Microeletromecânicos , Transdutores , Desenho de Equipamento , Ultrassom , Ultrassonografia
11.
J Integr Plant Biol ; 63(1): 126-145, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32678945

RESUMO

Melatonin is a pleiotropic molecule with multiple functions in plants. Since the discovery of melatonin in plants, numerous studies have provided insight into the biosynthesis, catabolism, and physiological and biochemical functions of this important molecule. Here, we describe the biosynthesis of melatonin from tryptophan, as well as its various degradation pathways in plants. The identification of a putative melatonin receptor in plants has led to the hypothesis that melatonin is a hormone involved in regulating plant growth, aerial organ development, root morphology, and the floral transition. The universal antioxidant activity of melatonin and its role in preserving chlorophyll might explain its anti-senescence capacity in aging leaves. An impressive amount of research has focused on the role of melatonin in modulating postharvest fruit ripening by regulating the expression of ethylene-related genes. Recent evidence also indicated that melatonin functions in the plant's response to biotic stress, cooperating with other phytohormones and well-known molecules such as reactive oxygen species and nitric oxide. Finally, great progress has been made towards understanding how melatonin alleviates the effects of various abiotic stresses, including salt, drought, extreme temperature, and heavy metal stress. Given its diverse roles, we propose that melatonin is a master regulator in plants.


Assuntos
Frutas/metabolismo , Melatonina/metabolismo , Óxido Nítrico/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo
12.
J Pineal Res ; 68(4): e12642, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32092171

RESUMO

Melatonin is a universal regulator modulating plant development and responses to abiotic stresses. The alteration and potential roles of melatonin in mediating aluminum (Al) tolerance were investigated in two wheat genotypes differing in Al resistance. Using the high-resolution mass spectrometry, we observed that melatonin contents in Xi Aimai-1 were 1.7-fold higher than that in Yangmai-5. Application of melatonin conferred Al resistance in both genotypes. Melatonin treatment scavenged reactive oxygen species (ROS) accumulation and alleviated Al-induced oxidative damage to lipids and proteins by stimulating antioxidant enzymes and augmenting antioxidants. Additionally, melatonin treatment decreased root tip-Al contents by 19.0% and 15.5% in Xi Aimai-1 and Yangmai-5, respectively. Malate efflux, however, was not altered by melatonin under Al stress. The amount of cell wall polysaccharide and pectin methylesterase activity was significantly increased by Al treatment; but suppressed by melatonin. Melatonin synthesis inhibitor, p-CPA, significantly increased the amount of the Al binding in cell walls of the tolerant genotype, whereas exogenous melatonin decreased cell wall Al content in the sensitive genotype. These results suggest that melatonin alleviated Al toxicity through augmenting antioxidants and inducing antioxidant enzymes to control ROS and enhancing exclusion of Al from root apex by altering cell wall polysaccharides in wheat.


Assuntos
Alumínio/toxicidade , Homeostase/fisiologia , Melatonina/metabolismo , Triticum/metabolismo , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Homeostase/efeitos dos fármacos , Melatonina/farmacologia , Oxirredução , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico , Triticum/efeitos dos fármacos
13.
Plant Cell Rep ; 39(5): 567-575, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32025801

RESUMO

KEY MESSAGE: NADPH oxidase-mediated H2O2 maintains proline concentration under NaCl stress through regulating its biosynthesis and degradation, conferring salt tolerance to wheat plants. Considerable attention has been paid to the specific role of hydrogen peroxide (H2O2) in plant stress responses. Here, using microscopic, pharmacological and biochemical approaches, we explored H2O2 production and its roles in redox control under salt stress in wheat roots. Exogenous H2O2 pretreatment decreased salt-induced lipid peroxidation, while increased proline content in wheat roots. Salt stress led to a transient increase in NADPH oxidase activity accompanied by accumulation of H2O2 and proline in roots. The elevated proline accumulation in the presence of NaCl was significantly suppressed by diphenyleneiodonium, an inhibitor of NADPH oxidase, and dimethylthiourea, a scavenger of H2O2. The rate-limiting enzyme involved in proline biosynthesis, Δ1-pyrroline-5-carboxylate synthetase (P5CS), was induced by NaCl, whereas the house-keeping enzyme in proline degradation, proline dehydrogenase (ProDH), was inhibited. After 6 h, the activity of P5CS increased by 1.5-fold, whereas ProDH decreased by 13.9%. The levels of these enzymes, however, were restored by NADPH oxidase inhibitor or H2O2 scavenger. After treatment with H2O2, the effects of diphenyleneiodonium and or dimethylthiourea on proline content and activities of P5CS and ProDH were reversed. These results suggested that NADPH oxidase-mediated H2O2 alleviates oxidative damage induced by salt stress through regulating proline biosynthesis and degradation.


Assuntos
Peróxido de Hidrogênio/farmacologia , NADPH Oxidases/antagonistas & inibidores , Raízes de Plantas/metabolismo , Prolina/metabolismo , Estresse Salino/efeitos dos fármacos , Plântula/metabolismo , Triticum/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Membrana Celular/patologia , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , NADPH Oxidases/metabolismo , Oniocompostos/farmacologia , Ornitina-Oxo-Ácido Transaminase/metabolismo , Raízes de Plantas/efeitos dos fármacos , Prolina Oxidase/metabolismo , Salinidade , Estresse Salino/fisiologia , Tolerância ao Sal/efeitos dos fármacos , Tolerância ao Sal/fisiologia , Plântula/efeitos dos fármacos , Plântula/enzimologia , Tioureia/análogos & derivados , Tioureia/farmacologia , Triticum/efeitos dos fármacos , Triticum/enzimologia
14.
J Sci Food Agric ; 100(15): 5412-5421, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32562270

RESUMO

BACKGROUND: Phenolic compounds are phytochemicals present in vegetables which contribute to human health. Although nitrogen deficiency and sucrose (Suc) are linked to phenolic production in vegetables, the relationship between them in the regulation of phenolic biosynthesis remains unknown. This study investigated the potential role of Suc in regulating phenolic biosynthesis of lettuce under low-nitrogen (LN) conditions. RESULTS: Our results showed that LN treatment significantly increased Suc content in lettuce by inducing rapid increases in activities of sucrose synthesis-related enzymes. Exogenous Suc further stimulated LN-induced phenolic accumulation in lettuce by upregulating the expression of genes (PAL, CHS, F3H, DFR, F35H and UFGT) involved in phenolic biosynthesis. The opposite effects were true for exogenous 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) application. No changes were observed in chlorophyll content in LN-treated lettuce, in either the presence or absence of Suc application. Notably, exogenous DCMU resulted in decreases of maximum quantum efficiency of photosystem II (PSII) photochemistry, actual efficiency of PSII and electron transport rate in PSII and increase of quantum yield of non-regulated energy dissipation in PSII in lettuce under LN conditions, whereas these effects were reversed on Suc application. Exogenous Suc also increased glutamine synthetase and glutamate synthase activities in LN-treated lettuce. CONCLUSIONS: These results suggest that Suc is involved in LN-induced phenolic production in lettuce by enhancing photosynthetic and nitrogen assimilation efficiency to increase the supply of carbon resources and precursors for phenolic biosynthesis. © 2020 Society of Chemical Industry.


Assuntos
Lactuca/metabolismo , Nitrogênio/metabolismo , Fenóis/metabolismo , Sacarose/metabolismo , Clorofila/análise , Clorofila/metabolismo , Lactuca/química , Lactuca/crescimento & desenvolvimento , Nitrogênio/análise , Fenóis/análise , Fotossíntese , Folhas de Planta/química , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Sacarose/análise , Verduras/química , Verduras/crescimento & desenvolvimento , Verduras/metabolismo
15.
J Orthop Sci ; 24(2): 342-346, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30389310

RESUMO

BACKGROUND: Osteofibrous dysplasia usually progresses until ten years of age and occasionally regresses spontaneously after puberty. Patients with osteofibrous dysplasia usually require close observation. Surgery is an option considered only for extensive, deforming lesions and those with pathological fractures and rapid progression prior to puberty. If surgery is indicated, the traditional intra-lesional curettage or subperiosteal resection usually leads to high recurrence. Hence, extraperiosteal wide excision and various methods of reconstruction after resection have been advocated for this lesion. We reviewed the clinical results of patients managed with extraperiosteal segmental excision and reconstruction by liquid nitrogen-treated tumor-bearing autograft combined with allograft. METHODS: From January 2010 to December 2014, twelve patients with final diagnosis of tibial osteofibrous dysplasia were studied retrospectively. All these patients were treated with extraperiosteal segmental excision and reconstruction by liquid nitrogen-treated tumor-bearing autograft combined with allograft. RESULTS: The patient group consisted of 5 males and 7 females, with a median age of 13 years (6-24 years). 3 lesions were located in left tibia and 9 in right. The median length of resected segment was 8 cm (5-11 cm). The patients were followed for 36-84 months (median 52 months). Follow-up radiographs showed that the median time for complete union of the grafted bone was 9 months (6-15 months). There was no evidence of recurrence. All patients had full range of motion in the knee and ankle joints after surgery. CONCLUSIONS: Extraperiosteal segmental excision for osteofibrous dysplasia of tibia with reconstruction by liquid nitrogen-treated recycled autograft and allograft is a good surgical option to prevent recurrence and fill bone defects in this rare lesion.


Assuntos
Doenças do Desenvolvimento Ósseo/cirurgia , Neoplasias Ósseas/cirurgia , Osteotomia/métodos , Procedimentos de Cirurgia Plástica/métodos , Tíbia/cirurgia , Adolescente , Aloenxertos , Autoenxertos , Doenças do Desenvolvimento Ósseo/diagnóstico por imagem , Doenças do Desenvolvimento Ósseo/patologia , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/patologia , Placas Ósseas , Criança , Estudos de Coortes , Terapia Combinada , Curetagem/métodos , Feminino , Humanos , Masculino , Nitrogênio/farmacologia , Osteotomia/instrumentação , Periósteo/cirurgia , Cuidados Pós-Operatórios/métodos , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Tíbia/patologia , Resultado do Tratamento , Cicatrização/fisiologia , Adulto Jovem
16.
J Cell Biochem ; 119(12): 9899-9909, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30132953

RESUMO

Osteosarcoma (OS) is an aggressive malignant tumor of bone, which often occurs in children and adolescents. Currently, the effective method for the treatment of OS is still limited. The study aimed to investigate the synergistic antitumor effect of inositol polyphosphate-4-phosphatase, type-II (INPP4B) and rucaparib on OS cells. The expression levels of INPP4B in OS tissues and OS cell lines were examined by quantitative real-time polymerase chain reaction and Western blot analysis. SaOS2 and U2OS cells were then transfected with overexpression vector of INPP4B or were treated with different concentrations of rucaparib, and cell viability, cell cycle, and apoptosis were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and flow cytometry. Western blot assay uncovered the combined effects of INPP4B and rucaparib on cell cycle, apoptosis and phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) signal pathway. Further, the tumor formation was examined in vivo. Results showed that INPP4B was low expressed in OS tissues and in OS cell lines. INPP4B overexpression significantly decreased cell viability and induced apoptosis in SaOS2 and U2OS cells. Additionally, rucaparib remarkably reduced cell viability in a dose-dependent and time-dependent manner. Meanwhile, rucaparib suppressed cell cycle progression in the S phase and promoted apoptosis in a dose-dependent manner. Further, combination of INPP4B overexpression and rucaparib declined Myc, cyclin E1 and cyclin D1 expressions, enhanced Bad, Bax, and cleaved-caspase-3 expressions, and blocked PI3K/AKT signal pathway in SaOS2 and U2OS cells. Finally, combination of INPP4B overexpression and rucaparib inhibited tumor formation in vivo. The study demonstrated that INPP4B and rucaparib exhibited synergistic antitumor effect by regulating PI3K/AKT pathway in OS cells.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Ósseas/tratamento farmacológico , Indóis/farmacologia , Osteossarcoma/tratamento farmacológico , Monoéster Fosfórico Hidrolases/farmacologia , Transdução de Sinais , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/fisiopatologia , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Criança , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Indóis/uso terapêutico , Masculino , Osteossarcoma/genética , Osteossarcoma/metabolismo , Osteossarcoma/fisiopatologia , Fosfatidilinositol 3-Quinase/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Monoéster Fosfórico Hidrolases/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Adulto Jovem
17.
Anal Chem ; 90(18): 11040-11047, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30141618

RESUMO

Biotransformation is a notable modulator of the fate, bioaccumulation, and toxicity of contaminants in the environment. However, it is often formidable to identify unknown biotransformation products in the absence of reference standards, and this analytical challenge is particularly true for contaminants of emerging concern (CECs) that are mostly polar molecules without characteristic structures (e.g., Cl and Br) and in complex matrices such as plants. In this study, using the fibrate drug gemfibrozil as a model CEC and Arabidopsis thaliana as a model plant, we developed and demonstrated a novel analytical framework coupling deuterium stable isotope labeling with high-resolution mass spectrometry (SILAMS) in identifying plant biotransformation products. When exposed in A. thaliana cells, gemfibrozil was quickly taken up into the cells and extensively metabolized. The use of nonlabeled and deuterated gemfibrozil at a 3:1 ratio created unique diagnostic patterns in mass spectra, enabling the identification of 11 novel phase II amino acid/peptide conjugates. Similarity in mass fragmentation patterns and chromatographic behaviors was then employed to establish the probable structures. Two major metabolites were further confirmed as glutamate and glutamine conjugates using authentic standards. Most of the identified conjugates were also detected in the whole A. thaliana plant. Therefore, SILAMS offers unique advantages by excluding false matrix positives and helping discern unknown metabolites, including polar conjugates with endogenous biomolecules, with a high degree of confidence. This novel framework may be readily applied to other CECs for high-throughput metabolite screening in plants to improve our understanding of their food safety and human health risks and potential deleterious effects on other species living on plants.


Assuntos
Arabidopsis/metabolismo , Deutério/metabolismo , Poluentes Ambientais/metabolismo , Genfibrozila/metabolismo , Espectrometria de Massas/métodos , Biotransformação , Humanos , Marcação por Isótopo/métodos
18.
Med Sci Monit ; 24: 9196-9203, 2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30560838

RESUMO

BACKGROUND Prostatic calculi are common in urological treatments. Our major purpose in the present study was to explore the occurrence and composition of prostatic calculi, and investigate the effect of calcium oxalate (CaOx) on clusterin expression and lower urinary tract symptom (LUTS) in prostatitis and benign prostatic hyperplasia (BPH) patients with calculi. MATERIAL AND METHODS From December 2016 to January 2017, a total of 79 prostatitis patients aged more than 50 years were enrolled. The patients were divided into 3 groups: group A had small calculi (discrete, small echoes); group B had large calculi (large masses of multiple echoes, much coarser), and group C had no calculi. Immunohistochemical analysis was performed to evaluate the tissue scores. The clusterin expression was detected by quantitative real-time CR (qRT-PCR), Western blot, and immunofluorescence. RESULTS According to multifactor analysis, age was significantly associated with prostatic calculus. The composition of prostatic calculus was an independent factor of LUTS. The clusterin expression was elevated in group B. The mRNA and protein levels of clusterin in prostatitis and BPH patients with stones were obviously higher than those in prostatitis and BPH patients without stones. CaOx enhanced clusterin expression in a dose-dependent manner. CONCLUSIONS Large prostatic calculi were associated with LUST. Furthermore, CaOx enhanced clusterin expression, leading to large prostatic calculi. These results may provide a therapeutic strategy for prostatitis and BPH.


Assuntos
Oxalato de Cálcio/farmacologia , Clusterina/efeitos dos fármacos , Sintomas do Trato Urinário Inferior/tratamento farmacológico , Idoso , Cálculos , China , Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/complicações , Prostatismo/complicações , Prostatismo/tratamento farmacológico , Prostatite/complicações , Prostatite/tratamento farmacológico
19.
J Exp Bot ; 67(3): 979-89, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26663393

RESUMO

Nitric oxide (NO) is an important bioactive molecule involved in cell wall metabolism, which has been recognized as a major target of aluminium (Al) toxicity. We have investigated the effects of Al-induced NO production on cell wall composition and the subsequent Al-binding capacity in roots of an Al-sensitive cultivar of wheat (Triticum aestivum L. cv. Yang-5). We found that Al exposure induced NO accumulation in the root tips. Eliminating NO production with an NO scavenger (cPTIO) significantly alleviated the Al-induced inhibition of root growth and thus reduced Al accumulation. Elimination of NO, however, did not significantly affect malate efflux or rhizosphere pH changes under Al exposure. Levels of cell wall polysaccharides (pectin, hemicelluloses 1, and hemicelluloses 2) and pectin methylesterase activity, as well as pectin demethylation in the root apex, significantly increased under Al treatment. Exogenous cPTIO application significantly decreased pectin methylesterase activity and increased the degree of methylation of pectin in the root cell wall, thus decreasing the Al-binding capacity of pectin. These results suggest that the Al-induced enhanced production of NO decreases cell wall pectin methylation, thus increasing the Al-binding capacity of pectin and negatively regulating Al tolerance in wheat.


Assuntos
Alumínio/metabolismo , Parede Celular/metabolismo , Óxido Nítrico/metabolismo , Pectinas/metabolismo , Raízes de Plantas/metabolismo , Triticum/metabolismo , Benzoatos/farmacologia , Hidrolases de Éster Carboxílico/metabolismo , Parede Celular/efeitos dos fármacos , Azul Evans/metabolismo , Sequestradores de Radicais Livres/farmacologia , Concentração de Íons de Hidrogênio , Imidazóis/farmacologia , Malatos/metabolismo , Metilação/efeitos dos fármacos , Modelos Biológicos , Óxido Nítrico/biossíntese , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/ultraestrutura , Triticum/efeitos dos fármacos , Triticum/enzimologia , Triticum/ultraestrutura , Ácidos Urônicos/metabolismo
20.
Appl Microbiol Biotechnol ; 99(1): 477-87, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25172135

RESUMO

Nitrification inhibitors (NIs) 3,4-dimethylpyrazole phosphate (DMPP) and dicyandiamide (DCD) have been used extensively to improve nitrogen fertilizer utilization in farmland. However, their comparative effects on ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) in agricultural soils are still unclear. Here, we compared the impacts of these two inhibitors on soil nitrification, AOA and AOB abundance as well as their community structure in a vegetable soil by using real-time PCR and terminal restriction fragment length polymorphism (T-RFLP). Our results showed that urea application significantly increased the net nitrification rates, but were significantly inhibited by both NIs, and the inhibitory effect of DMPP was significantly greater than that of DCD. AOB growth was more greatly inhibited by DMPP than by DCD, and the net nitrification rate was significantly related to AOB abundance, but not to AOA abundance. Application of urea and NIs to soil did not change the diversity of the AOA community, with the T-RFs remaining in proportions that were similar to control soils, while the community structure of AOB exhibited obvious shifts within all different treatments compared to the control. Phylogenetic analysis showed that all AOA sequences fell within group 1.1a and group 1.1b, and the AOB community consisted of Nitrosospira cluster 3, cluster 0, and unidentified species. These results suggest that DMPP exhibited a stronger inhibitory effect on nitrification than DCD by inhibiting AOB rather than AOA.


Assuntos
Archaea/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Biota/efeitos dos fármacos , Guanidinas/metabolismo , Pirazóis/metabolismo , Microbiologia do Solo , Archaea/crescimento & desenvolvimento , Bactérias/crescimento & desenvolvimento , Análise por Conglomerados , DNA Arqueal/química , DNA Arqueal/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Dados de Sequência Molecular , Nitrificação/efeitos dos fármacos , Filogenia , Polimorfismo de Fragmento de Restrição , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Verduras/crescimento & desenvolvimento
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