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1.
J Biol Regul Homeost Agents ; 34(5): 1669-1677, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33111516

RESUMO

The purpose of this study was to explore the mitigating effect of morphine on the myocardial ischemia-reperfusion injury (MIRI) in rats through the cyclic adenosine monophosphate/protein kinase A (cAMP/PKA) pathway. A total of 30 male Wistar rats were assigned into sham group, MIRI group and morphine group using a random number table. The model of MIRI was routinely established. Then, the pathological changes in the morphology of myocardial tissues were observed via hematoxylin-eosin (HE) staining. The levels of the oxidative stress indicators superoxide dismutase (SOD) and malondialdehyde (MDA), the content of the inflammatory cytokine tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1ß) and IL-6 and the quantity of glutathione peroxidase (GSH-Px), lactate dehydrogenase (LDH), creatine kinase (CK), CK-MB and cardiac troponin I (cTnI) in the myocardial enzyme spectrum were determined and analyzed through enzyme-linked immunosorbent assay (ELISA). Moreover, the messenger ribonucleic acid (mRNA) and protein expressions of cAMP, PKA, cAMP-response element binding protein (CREB) and phosphorylated CREB (p-CREB) in the cAMP/PKA signaling pathway in the myocardial tissues were measured using real-time polymerase chain reaction (PCR) and Western blotting, respectively. The results manifested that compared with those in MIRI group, the levels of myocardial infarct size, LDH, CK, CK-MB, cTnI, MDA, TNF-α, IL-1ß, IL-6 and p-CREB were decreased, while the levels of GSH-Px, SOD, PKA and CREB were increased in the morphine group. In conclusion, morphine may mitigate MIRI in rats through the cAMP/PKA signaling pathway.


Assuntos
Traumatismo por Reperfusão Miocárdica , Animais , Proteínas Quinases Dependentes de AMP Cíclico , Masculino , Morfina , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio , Ratos , Ratos Wistar , Transdução de Sinais
2.
Sci Robot ; 4(28)2019 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-33137750

RESUMO

Simulation systems have become essential to the development and validation of autonomous driving (AD) technologies. The prevailing state-of-the-art approach for simulation uses game engines or high-fidelity computer graphics (CG) models to create driving scenarios. However, creating CG models and vehicle movements (the assets for simulation) remain manual tasks that can be costly and time consuming. In addition, CG images still lack the richness and authenticity of real-world images, and using CG images for training leads to degraded performance. Here, we present our augmented autonomous driving simulation (AADS). Our formulation augmented real-world pictures with a simulated traffic flow to create photorealistic simulation images and renderings. More specifically, we used LiDAR and cameras to scan street scenes. From the acquired trajectory data, we generated plausible traffic flows for cars and pedestrians and composed them into the background. The composite images could be resynthesized with different viewpoints and sensor models (camera or LiDAR). The resulting images are photorealistic, fully annotated, and ready for training and testing of AD systems from perception to planning. We explain our system design and validate our algorithms with a number of AD tasks from detection to segmentation and predictions. Compared with traditional approaches, our method offers scalability and realism. Scalability is particularly important for AD simulations, and we believe that real-world complexity and diversity cannot be realistically captured in a virtual environment. Our augmented approach combines the flexibility of a virtual environment (e.g., vehicle movements) with the richness of the real world to allow effective simulation.

3.
J Hazard Mater ; 170(2-3): 1156-63, 2009 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-19541411

RESUMO

Chelate-assisted phytoextraction by high biomass producing plant species enhances the removal of heavy metals from polluted environments. In this regard, Juncus effusus a wetland plant has great potential. This study evaluated the effects of elevated levels of manganese (Mn) on the vegetative growth, Mn uptake and antioxidant enzymes in J. effusus. We also studied the role of citric acid and EDTA on improving metal accumulation, plant growth and Mn toxicity stress alleviation. Three-week-old plantlets of J. effusus were subjected to various treatments in the hydroponics as: Mn (50, 100 and 500 microM) alone, Mn (500 microM) + citric acid (5 mM), and Mn (500 microM) + EDTA (5 mM). After 2 weeks of treatment, higher Mn concentrations significantly reduced the plant biomass and height. Both citric acid and EDTA restored the plant height as it was reduced at the highest Mn level. Only the citric acid (but not EDTA) was able to recover the plant biomass weight, which was also obvious from the microscopic visualization of mesophyll cells. There was a concentration dependent increase in Mn uptake in J. effusus plants, and relatively more deposition in roots compared to aerial parts. Although both EDTA and citric acid caused significant increase in Mn accumulation; however, the Mn translocation was enhanced markedly by EDTA. Elevated levels of Mn augmented the oxidative stress, which was evident from changes in the activities of antioxidative enzymes in plant shoots. Raised levels of lipid peroxidation and variable changes in the activities of antioxidant enzymes were recorded under Mn stress. Electron microscopic images revealed several modifications in the plants at cellular and sub-cellular level due to the oxidative damage induced by Mn. Changes in cell shape and size, chloroplast swelling, increased number of plastoglobuli and disruption of thylakoid were noticed. However, these plants showed a high degree of tolerance against Mn toxicity stress, and it removed substantial amounts of Mn from the media. The EDTA best enhanced the Mn uptake and translocation, while citric acid best recovered the plant growth.


Assuntos
Ácido Cítrico/química , Ácido Cítrico/farmacologia , Manganês/química , Desenvolvimento Vegetal , Plantas/metabolismo , Antioxidantes/metabolismo , Biomassa , Quelantes/farmacologia , Cloroplastos/efeitos dos fármacos , Cloroplastos/ultraestrutura , Glutationa Redutase/química , Peroxidação de Lipídeos , Malondialdeído , Manganês/isolamento & purificação , Microscopia Eletrônica de Transmissão , Peroxidase/química , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/ultraestrutura , Plantas/ultraestrutura , Superóxido Dismutase/química
4.
Plant Cell Environ ; 29(10): 1970-9, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16930322

RESUMO

Sodium chloride reduces the growth of rice seedlings, which accumulate excessive concentrations of sodium and chloride ions in their leaves. In this paper, we describe how silicon decreases transpirational bypass flow and ion concentrations in the xylem sap in rice (Oryza sativa L.) seedlings growing under NaCl stress. Salt (50 mM NaCl) reduced the growth of shoots and roots: adding silicate (3 mM) to the saline culture solution improved the growth of the shoots, but not roots. The improvement of shoot growth in the presence of silicate was correlated with reduced sodium concentration in the shoot. The net transport rate of Na from the root to shoot (expressed per unit of root mass) was also decreased by added silicate. There was, however, no effect of silicate on the net transport of potassium. Furthermore, in salt-stressed plants, silicate did not decrease the transpiration, and even increased it in seedlings pre-treated with silicate for 7 d prior to salt treatment, indicating that the reduction of sodium uptake by silicate was not simply through a reduction in volume flow from root to shoot. Experiments using trisodium-8-hydroxy-1,3,6-pyrenetrisulphonic acid (PTS), an apoplastic tracer, showed that silicate dramatically decreased transpirational bypass flow in rice (from about 4.2 to 0.8%), while the apparent sodium concentration in the xylem, which was estimated indirectly from the flux data, decreased from 6.2 to 2.8 mM. Direct measurements of the concentration of sodium in xylem sap sampled using Philaenus spumarius confirmed that the apparent reduction was not a consequence of sodium recycling. X-ray microanalysis showed that silicon was deposited in the outer part of the root and in the endodermis, being more obvious in the latter than in the former. The results suggest that silicon deposition in the exodermis and endodermis reduced sodium uptake in rice (Oryza sativa L.) seedlings under NaCl stress through a reduction in apoplastic transport across the root.


Assuntos
Oryza/metabolismo , Raízes de Plantas/metabolismo , Silício/metabolismo , Transporte Biológico , Microanálise por Sonda Eletrônica , Fluorescência , Potássio/metabolismo , Cloreto de Sódio/administração & dosagem , Cloreto de Sódio/metabolismo
5.
Leuk Lymphoma ; 12(5-6): 463-70, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8180609

RESUMO

The characterization of a cell line (designated SR-91) from a patient with clinical and morphological diagnosis of acute lymphoblastic leukemia (CD3-, CD2+, CD7+, germline TCR genes) who relapsed early after allogeneic bone marrow transplantation, is reported. The line was established from blood cells obtained at diagnosis and placed in suspension culture with medium conditioned by 5637 cells. SR-91 cells are negative for lymphoid surface markers (CD3-, CD2-, CD7-) but positive for markers indicative of myeloid progenitor cells, such as CD33 and CD34. It is likely that the conditioned medium has induced myeloid differentiation from a lymphohematopoietic progenitor cell. After establishment, cells proliferated in response to GM-CSF stimulation but they are not factor-dependent and do not produce GM-CSF. No proliferative response to IL-1, IL-2, IL-3, IL-4, IL-6 or M-CSF was observed. Cells were completely resistant to anti-proliferative effects of tumor necrosis factor-alpha and interferon-alpha or -gamma, and showed no lysis after incubation with freshly isolated natural killer cells or IL-2-activated natural killer cells.


Assuntos
Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Adulto , Northern Blotting , Linhagem Celular , Citocinas/biossíntese , Citotoxicidade Imunológica , Células-Tronco Hematopoéticas/imunologia , Humanos , Imunofenotipagem , Células Matadoras Naturais/imunologia , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Células Tumorais Cultivadas
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