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1.
Opt Lett ; 44(19): 4801-4804, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31568446

RESUMO

We propose a controlled-PHASE gate for neutral atoms in which one of the qubit state components adiabatically evolves along the multiple-atom eigenstate formed by the chirped laser pulse coupling to Rydberg states and intrinsic dipole-dipole exchange interactions and, consequently, accumulates an interaction-induced geometric phase. The geometric Rydberg gate is not limited by an adiabatic condition, which is sped up by shortcuts to adiabaticity (STA). Analyses show that an STA scheme is more robust than a non-adiabatic case against the variations of control parameters and faster than an adiabatic case, which protects from the decay of Rydberg states. Furthermore, an intermediate value of dipole-dipole interaction strength is enough for our scheme.

2.
Biomed Pharmacother ; 120: 109378, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31541885

RESUMO

Bone homeostasis is known as a dynamic balance, including bone formation through osteoblasts and bone resorption by osteoclasts. MicroRNAs (miRs) play a critical role in regulating bone formation and homeostasis. In the study, the effects of miR-451a on bone homeostasis were investigated. The results indicated that the primary osteoblasts and mesenchymal stem cells (MSCs), as the main source of osteoblasts, isolated from miR-451a-knockout (KO) mice showed promoted osteogenesis. in vivo, an ovariectomized (OVX) animal model was used to further explore the effect of miR-451a on osteoporosis. Micro-computed tomography (µCT) indicated a promoted bone volume in miR-451a-KO mice compared to wild-type (WT) mice after OVX operation, demonstrating a redundant bone formation after the knockout of miR-451a. Importantly, we for the first time found that bone morphogenetic protein 6 (Bmp6) was a direct target of miR-451a, elevating bone formation through regulating SMAD1/5/8 expression. In conclusion, reducing miR-451a expression levels could enhance bone formation during the progression of osteoporosis, which might be at least partly via the meditation of Bmp6 expression.

3.
ACS Appl Mater Interfaces ; 11(30): 27318-27326, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31284718

RESUMO

Textile is a kind of emerging substrate for wearable printed electronics to realize recyclable smart products by versatile and low-cost screen printing. The high temperature sintering step is necessary to get high surface electrical conductivity, whereas most of the common fabrics have poor temperature endurance. Meanwhile, both rough surface and porous structure of fabrics are not beneficial to obtain high-resolution and high-quality circuits. In this work, the ultraviolet (UV) curable conductive inks with low-temperature and short-time curing were developed for screen-printing e-textiles, and the rheological behavior of conductive inks with different polymer contents was characterized in order to determine the ink formulation suitable for screen printing on fabrics. To demonstrate the usability of the developed ink in fabricating e-textiles, the conductive lines with different widths as well as the antenna for UHF RFID tags were screen-printed on plain nylon-woven fabrics. The geometric morphology and the electrical properties of the printed conductive lines were evaluated. The results showed that the screen-printed conductive lines have a minimum line width of 0.2 mm, highest conductivity of 6.02 × 106 S m-1, and good bending endurance at a bending radius of 5 mm. Also, the feasibility of UV curable conductive ink for a fabric-based electronic device was confirmed by the screen-printed antenna of UHF RFID tags, and the reading distance after five cycles of washing is still over 3.0 m. Generally, this work developed a kind of low-temperature curing ink characterized by direct screen printing on common fabrics and high electrical conductivity after curing, and it will facilitate the use of textiles as the screen-printed substrates for flexible and wearable electronic devices.

4.
Chemistry ; 25(22): 5787-5792, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30786080

RESUMO

Over the last decade, the controllable reversible phase transition of functional materials has received growing interest as it shows unique suitability for various technological applications. Although many metal-organic frameworks (MOFs) possess a lamellar structure, the reversible structural transformation of MOFs between their three-dimensional (3D) phase and two-dimensional (2D) phase remains a largely unexplored area. Herein, we report for the first time a europium MOF with unprecedented reversible morphology in different solvents at room temperature. This europium MOF displayed a 3D nanorod morphology in organic solvent and a 2D nanobelt architecture in water. As a proof of concept for potential applications of this reversible-phase-transition MOF, we were able to use a delamination recovery method to load dye molecules that previously could not be loaded into europium MOFs.

5.
Medicine (Baltimore) ; 98(1): e13769, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30608387

RESUMO

This study aims to evaluate the effectiveness and safety of the application of a 3-dimensional (3D)-printed composite guide plate for atlantoaxial pedicle screw.This was a retrospective study. A total of 43 atlantoaxial dislocation patients admitted in our hospital between January 2014 and October 2016 were retrospectively analyzed. According to the different methods of operation, patients were divided into 2 groups: 3D-printed plate group (n = 19) and traditional fixation group (n = 24). Placement time, operation duration, fluoroscopy number, intraoperative bleeding volume, and the neck and shoulder pain visual analog scale and Japanese Orthopaedic Association cervical nerve function scores were compared between pre- and postoperation.Differences in general data between these 2 groups were not statistically significant (P > .05). For patients in the 3D-printed plate group, a total of 68 assisting screws were placed at the pedicle, the accuracy rate of screw placement was 94.1%, placement time was 2.2 ±â€Š0.4 minutes, fluoroscopy number was 4.6 ±â€Š1.1 times, operation duration was 197 ±â€Š41 minutes, and intraoperative bleeding volume was 395 ±â€Š64 mL. In the traditional fixation group, a total of 76 screws were placed at the pedicle of patients, the accuracy rate of screw placement was 76.3%, placement time was 3.4 ±â€Š0.7 minutes, fluoroscopy number was 9.4 ±â€Š2.7 times, operation duration was 245 ±â€Š67 minutes, and intraoperative bleeding volume was 552 ±â€Š79 mL. Differences in accuracy rate, placement time, fluoroscopy number, operation duration, and intraoperative bleeding volume between these 2 groups were statistically significant (P < .05).The effectiveness and safety of 3D-printed composite guide plate for atlantoaxial pedicle screw were better than traditional method.


Assuntos
Articulação Atlantoaxial/cirurgia , Placas Ósseas , Luxações Articulares/cirurgia , Parafusos Pediculares , Impressão Tridimensional , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
6.
Mol Med Rep ; 18(6): 5663-5668, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30387846

RESUMO

Hepatic ischemia/reperfusion injury (HIRI) serves a causative role in postoperative hepatocyte death; however, the mechanisms underlying HIRI remain unclear. Mitochondrial autophagy, with apoptosis, cell cycle distribution and DNA damage repair, may be regarded as a regulatory factor post­HIRI. Parkin, a novel ubiquitin ligase, has been reported to increase mitochondrial autophagy and decrease apoptosis. However, the association between Parkin, mitochondrial autophagy and other regulatory factors in HIRI is unclear. In the present study, the effects of Parkin on HIRI were investigated, using hepatocytes and livers from male Sprague Dawley rats subjected to simulated in vivo HIRI. The results of the present study demonstrated that Parkin expression and mitochondrial autophagy were upregulated post­HIRI, leading to decreased hepatocyte death. Parkin knockdown suppresses the level of mitochondrial autophagy and promotes hepatocyte apoptosis by suppressing apoptosis regulator Bcl­2 function post­HIRI. In addition, Parkin deficiency alters cell cycle distribution and impairs DNA damage repair post­HIRI. In conclusion, Parkin facilitates mitochondrial autophagy and DNA damage repair, inhibits apoptosis, and modulates the cell cycle, leading to increased hepatocyte survival, demonstrating that Parkin may act as a protective regulatory factor post HIRI.

7.
BMC Surg ; 18(1): 108, 2018 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-30477462

RESUMO

BACKGROUND: Laparoscopic splenectomy (LS) is regarded as a second-line treatment for medically refractory idiopathic thrombocytopenic purpura (ITP), but the predictive factors for the long-term postoperative responses to ITP are still a matter of debate. We aimed to investigate the factors that can predict the long-term response after LS for Chinese patients with medically refractory ITP. METHODS: From January 2011 to September 2016, 78 Chinese patients with ITP who underwent LS were retrospectively analyzed. Twelve parameters were analyzed by univariate and multivariate methods. RESULTS: Univariate analysis revealed that platelet count on preoperative day (PRD) 1 (P < 0.001) and operative time (P = 0.011) were significantly associated with long-term response of ITP after LS. Multivariate analysis revealed that platelet count on PRD 1 was a predictive factor of long-term response (P < 0.001). Furthermore, a long-term, stable response of platelet count on PRD 1 of > 30.0 × 109/L was easier to achieve than a platelet count on PRD 1 ≤ 30.0 × 109/L after LS for ITP. CONCLUSIONS: LS is a valuable and effective option in the treatment of medically refractory ITP. Platelet count on PRD 1 is an independent predicting factor for long-term response after LS for Chinese patients with ITP.

8.
J Acoust Soc Am ; 144(2): EL100, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30180673

RESUMO

Both specific airflow resistance and air permeability can be used as a parameter to estimate the sound absorption of textiles. The measurement of specific airflow resistance is specified in ISO 9053 (Int. Standards Org., 1991), but it is known to be inaccurate for low specific airflow resistance. This paper compares the measured specific airflow resistance according to ISO 9053 and those calculated from air permeability according to ISO 9237 (Int. Standards Org., 1995). The sound absorption coefficients predicted by Pieren's model [R. Pieren, Textile Res. J. 82(9), 864-874 (2012)] are compared with measurements by the impedance tube method, which concludes that those predicted from the air permeability are more accurate than those from the measured specific airflow resistance for textiles.

9.
World J Radiol ; 10(8): 83-90, 2018 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-30190800

RESUMO

AIM: To investigate the utility of renal diffusion tensor imaging (DTI) to detect early renal damage in patients with type 2 diabetes. METHODS: Twenty-six diabetic patients (12 with microalbuminuria (MAU), and 14 with normoalbuminuria) and fourteen healthy volunteers were prospectively included in this study. Renal DTI on 3.0 T MR was performed, and estimated glomerular filtration rate (eGFR) was recorded for each subject. Mean cortical and medullary fractional anisotropy (FA) values were calculated by placing multiple representative regions of interest. Mean FA values were statistically compared among groups. Correlations between FA values and eGFR were evaluated. RESULTS: Both cortical and medullary FA were significantly reduced in diabetic patients compared to healthy controls (0.403 ± 0.064 vs 0.463 ± 0.047, P = 0.004, and 0.556 ± 0.084 vs 0.645 ± 0.076, P = 0.002, respectively). Cortical FA was significantly lower in diabetic patients with NAU than healthy controls (0.412 ± 0.068 vs 0.463 ± 0.047, P = 0.02). Medullary FA in diabetic patients with NAU and healthy controls were similar (0.582 ± 0.096 vs 0.645 ± 0.076, P = 0.06). Both cortical FA and medullary FA correlated with eGFR (r = 0.382, P = 0.015 and r = 0.552, P = 0.000, respectively). CONCLUSION: FA of renal parenchyma on DTI might serve as a more sensitive biomarker of early diabetic nephropathy than MAU.

10.
Int Immunopharmacol ; 64: 319-325, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30243067

RESUMO

Psoriasis is a usual immune-mediated inflammatory skin disease with undefined pathogenesis. Aromatic-turmerone (ATM) is a mainly constituent of essential oil from Curcuma longa L. It has been shown to exhibit strong anti-oxidant, anti-tumor activities and anti-inflammatory effects. In this study, we investigated the effects of ATM on imiquimod (IMQ)-induced psoriasis-like BALB/c mice and its molecular mechanisms for anti-inflammatory effect. ATM showed inhibition of the transfer of CD8+ T cells in epidermis, and reduced expression of NF-κB and COX-2 as well as phosphorylation of p38 MAPK. It also decreased the level of TNF-α and IL-6, and down-regulates IL-17 IL-22 and IL-23 mRNA synthesis. Notably, we demonstrated that topically applied ATM alleviated skin inflammation in IMQ-induced mice. These results indicate that ATM, a natural active compound exhibits anti-inflammatory activity and is a promising candidate molecule to treat inflammatory skin diseases, such as psoriasis.

11.
Cell Death Dis ; 9(9): 870, 2018 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-30158515

RESUMO

CDK5 activation promotes ischemic neuronal death in stroke, with the recognized activation mechanism being calpain-dependent p35 cleavage to p25. Here we reported that CDK5-Tyr15 phosphorylation by zinc induced CDK5 activation in brain ischemic injury. CDK5 activation and CDK5-Tyr15 phosphorylation were observed in the hippocampus of the rats that had been subjected to middle cerebral artery occlusion, both of which were reversed by pretreatment with zinc chelator; while p35 cleavage and calpain activation in ischemia were not reversed. Zinc incubation resulted in CDK5-Tyr15 phosphorylation and CDK5 activation, without increasing p35 cleavage in cultured cells. Site mutation experiment confirmed that zinc-induced CDK5 activation was dependent on Tyr15 phosphorylation. Further exploration showed that Src kinase contributed to zinc-induced Tyr15 phosphorylation and CDK5 activation. Src kinase inhibition or expression of an unphosphorylable mutant Y15F-CDK5 abolished Tyr15 phosphorylation, prevented CDK5 activation and protected hippocampal neurons from ischemic insult in rats. We conclude that zinc-induced CDK5-Tyr15 phosphorylation underlies CDK5 activation and promotes ischemic neuronal death in stroke.

12.
Biomed Rep ; 8(4): 319-324, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29541452

RESUMO

Hepatocellular carcinoma (HCC) is among the most common and fatal cancers. It is a multistage and multifactorial carcinoma, in which a number of factors serve roles in its initiation and progression. Small nucleolar RNAs (snoRNAs), considered to serve a role in various cancers, have recently been identified to have significant contributions to HCC tumorigenesis. Recent studies suggest that snoRNAs have a critical role in the pathogenesis of HCC. Moreover, detailed studies have demonstrated that various snoRNAs are involved in a range of biological processes associated with HCC, including initiation, proliferation, tumor growth, the cell cycle, apoptosis and metastasis. In the present review, an overview of recent studies to date has been provided, focusing on the association of snoRNAs with HCC. Based on the findings, further studies focusing on the association of snoRNAs with HCC are required to verify the diagnostic and therapeutic capacities of snoRNAs in HCC.

13.
Food Chem ; 241: 427-433, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28958550

RESUMO

Surface Enhanced Raman Scattering (SERS) spectroscopy technology is widely used in materials analysis, environmental monitoring, biomedical, food security and other fields. Flower-shaped silver nanoparticles have been successfully synthesized by a simple aqueous phase silver nitrate reduction by ascorbic acid in the presence of polyvinylpyrrolidone (PVP) surfactant. The nanoparticles diameters were adjusted from 450 to 1000nm with surface protrusions up to 10-25nm. The flower-shaped silver nanostructures obtained were used as stable SERS substrates with high SERS activity for detecting Rhodamine 6G (R6G), at a concentration of only 10-9mol/L, where the SERS signal is still clear. SERS spectroscopy of four different food colorants (e.g. food blue, tartrazine, sunset yellow, acid red) were analysed and the characteristic bands were identified. An improved principle component analysis (PCA) was used for four different food colorants detection, at concentrations down to about 10-8mol/L. Thus, the LOD of food blue, tartrazine, sunset yellow and acid red are 79.285µg/L, 5.3436µg/L, 45.238µg/L and 50.244µg/L, respectively.


Assuntos
Corantes de Alimentos/análise , Nanopartículas Metálicas , Povidona , Prata , Análise Espectral Raman
14.
Am J Transl Res ; 9(7): 3245-3257, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28804543

RESUMO

OBJECTIVE: The mechanism underlying the therapeutic effects of combi-molecule JDF12 on prostate cancer (PCa) DU145 cells remains still unclear. This study aimed to investigate the proteomic profile after JDF12 treatment in DU145 cells by comparing with that in Iressa treated cells and untreated cells. METHODS: MTT was used to evaluate drug cytotoxicity, DAPI staining was done to assess apoptosis of cells, and flow cytometry was used to analyze cell cycle. iTRAQ and qPCR were employed to obtain the proteomic profiles of JDF12 treated, Iressa treated, and untreated DU145 cells, and validate the expression of selected differentially expressed proteins, respectively. RESULTS: JDF12 could significantly inhibit the proliferation and increase the apoptosis of DU145 cells when compared with Iressa or blank group. In total, 5071 proteins were obtained, out of which, 42, including 21 up-regulated and 21 down-regulated proteins, were differentially expressed in JDF12 group when compared with Iressa and blank groups. The up-regulated proteins were mainly involved in DNA damage/repair and energy metabolism; while the down-regulated proteins were mainly associated with cell apoptosis. qPCR confirmed the expression of several biologically important proteins in DU145 cells after JDF12 treatment. CONCLUSION: The molecular mechanisms of DNA alkylating agents on PCa therapy that with the assistant of EGFR-blocker were revealed on proteomic level, which may increase the possible applications of DNA alkylating agents and JDF12 on PCa therapy.

15.
Food Chem ; 237: 974-980, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28764094

RESUMO

Flower-shaped silver nanoparticles have been successfully synthesized by a simple aqueous phase silver nitrate reduction by ascorbic acid in the presence of polyvinylpyrrolidone (PVP) surfactant. The nanoparticles diameters were adjusted from 450 to 1000nm with surface protrusions up to 10-25nm. The growth direction of silver nuclei is controlled by their degree of coating by PVP. The flower-shaped silver nanostructures obtained were used as stable Surface Enhanced Raman Scattering (SERS) substrates with high SERS activity for detecting Rhodamine 6G (R6G), at a concentration of only 10-9M, where the SERS signal is still clear. SERS spectra of the dye carmine was analysed and the characteristic bands were identified. An improved principle component analysis (PCA) was used for carmine detection, at concentrations down to 10-8M. The characteristic peaks of the carmine (1019, 1360, and 1573cm-1) remained at 10-8M. This indicated that the minimum detection limit of AgNP-based substrate for carmine is about 10-8M.


Assuntos
Nanopartículas Metálicas/química , Carmim , Povidona , Prata , Análise Espectral Raman
16.
PLoS One ; 12(8): e0182150, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28787459

RESUMO

Synaptic activity increases the resistance of neurons to diverse apoptotic insults; however, the underlying mechanisms remain less well understood. Zinc promotes cell survival under varied conditions, but the role of synaptically released zinc in the activity-dependent anti-apoptotic effect is unknown. Using cultured hippocampal slices and primary neurons we show that a typical apoptosis inducer-staurosporine (STP) was able to cause concentration-dependent apoptotic cell death in brain slices; Enhanced synaptic activity by bicuculline (Bic)/4-Aminopyridine (AP) treatment effectively prevented neurons from STP-induced cell apoptosis, as indicated by increased cell survival and suppressed caspase-3 activity. Application of Ca-EDTA, a cell membrane-impermeable zinc chelator which can efficiently capture the synaptically released zinc, completely blocked the neuronal activity-dependent anti-apoptotic effect. Same results were also observed in cultured primary hippocampal neurons. Therefore, our results indicate that synaptic activity improves neuronal resistance to apoptosis via synaptically released zinc.


Assuntos
Apoptose/fisiologia , Neurônios/fisiologia , Neuroproteção/fisiologia , Transmissão Sináptica/fisiologia , Zinco/metabolismo , 4-Aminopiridina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Bicuculina/farmacologia , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Quelantes/farmacologia , Relação Dose-Resposta a Droga , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Hipocampo/fisiologia , Masculino , Neurônios/efeitos dos fármacos , Neurônios/patologia , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Ratos Sprague-Dawley , Estaurosporina/toxicidade , Transmissão Sináptica/efeitos dos fármacos , Técnicas de Cultura de Tecidos
17.
Opt Express ; 25(14): 15786-15795, 2017 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-28789091

RESUMO

We reveal a novel topological property of the exceptional points in a two-level parity-time symmetric system and then propose a scheme to detect the topological exceptional points in the system, which is embedded in a larger Hilbert space constructed by a four-level cold atomic system. We show that a tunable parameter in the presented system for simulating the non-Hermitian Hamiltonian can be tuned to sweep the eigenstates through the exceptional points in parameter space. The non-trivial Berry phases of the eigenstates obtained in this loop from the exceptional points can be measured by the atomic interferometry. Since the proposed operations and detection are experimentally feasible, our scheme may pave a promising way to explore the novel properties of non-Hermitian systems.

18.
Medicine (Baltimore) ; 96(24): e7215, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28614270

RESUMO

This study aimed to assess the role of pre-designed route on computer tomography urography (CTU) in the ultrasound-guided percutaneous nephrolithotomy (PCNL) for renal calculus.From August 2013 to May 2016, a total of 100 patients diagnosed with complex renal calculus in our hospital were randomly divided into CTU group and control group (without CTU assistance). CTU was used to design a rational route for puncturing in CTU group. Ultrasound was used in both groups to establish a working trace in the operation areas. Patients' perioperative parameters and postoperative complications were recorded.All operations were successfully performed, without transferring to open surgery. Time of channel establishment in CTU group (6.5 ±â€Š4.3 minutes) was shorter than the control group (10.0 ±â€Š6.7 minutes) (P = .002). In addition, there was shorter operation time, lower rates of blood transfusion, secondary operation, and less establishing channels. The incidence of postoperative complications including residual stones, sepsis, severe hemorrhage, and perirenal hematoma was lower in CTU group than in control group.Pre-designing puncture route on CTU images would improve the puncturing accuracy, lessen establishing channels as well as improve the security in the ultrasound-guided PCNL for complex renal calculus, but at the cost of increased radiation exposure.


Assuntos
Cálculos Renais/diagnóstico por imagem , Cálculos Renais/cirurgia , Nefrostomia Percutânea , Tomografia Computadorizada por Raios X , Ultrassonografia de Intervenção , Urografia , Transfusão de Sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Duração da Cirurgia , Complicações Pós-Operatórias , Reoperação , Resultado do Tratamento
19.
Gen Comp Endocrinol ; 247: 34-45, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28410969

RESUMO

In the present study, seven phosphoinositide 3-kinase (PI3K) members (PI3KCa, PI3KCb, PI3KCd, PI3KCg, PI3KC2a, PI3KC2b and PI3KC3, respectively) were isolated and characterized from yellow catfish Pelteobagrus fulvidraco, and their roles in insulin-induced changes of protein metabolism were determined. These seven PI3Ks can be divided into three classes, class I (including PI3KCa, PI3KCb, PI3KCd and PI3KCg), class II (including PI3KC2a and PI3KC2b) and class III (only including PI3KC3). Compared with mammals, all of these members share similar domain structure. Their mRNAs were widely expressed across ten tested tissues (liver, white muscle, spleen, brain, gill, mesenteric fat, intestine, heart, kidney and ovary), but at variable levels. In the in vivo study, insulin treatment significantly increased hepatic protein content at 3h, accompanied with reduced plasma total amino acid contents and liver ALT activity, and with increased total RNA content and the mRNA levels of PI3KCb, PI3KC2a, AKT2, mTORC1 and S6K1 in liver. At 6h and 12h, insulin injection showed no significant effect on liver protein content and plasma total amino acid, but reduced liver ALT activity and increased liver total RNA and the mRNA levels of AKT2, mTORC1 and S6K1 in liver at 6h. In the in vitro study, insulin incubation also tended to increase protein content of hepatocytes, accompanied with reduced cell medium total amino acid contents and hepatocytes ALT activity, and increased total RNA content and the mRNA levels of PI3KCb, PI3KC2a, AKT2, mTORC1 and S6K1 in hepatocytes. However, insulin treatment showed no significant effect on GDH activity and mRNA expression of PI3KCa, PI3KCd, PI3KCg, PI3KC2b, PI3KC3 and eEF2 both in the in vivo and in vitro studies. Effects of insulin on the mRNA levels of eIF-4E and 4E-BP1 were different between the in vivo and in vitro studies, and also time-dependent. Compared to single insulin group, insulin+wortmannin group increased ALT activity at 6h but reduced T-RNA content at 6 and 12h. AKT2 and S6K1 mRNA levels at 6 and 12h, mRNA levels of mTORC1, 4E-BP1 and eEF2 at 3 and 6h, and EIF-4E mRNA levels at 3 and 12h, PI3KCb and PI3KC2a mRNA levels were significantly lower in insulin+wortmannin group than those in single insulin group. Thus, our study demonstrated that among seven PI3K members, PI3KCb and PI3KC2a were more sensitive to the insulin signaling pathway, and insulin stimulated hepatic protein synthesis in yellow catfish through PI3K signaling pathway.


Assuntos
Peixes-Gato/metabolismo , Insulina/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Sequência de Aminoácidos , Aminoácidos/sangue , Androstadienos/farmacologia , Animais , Sequência de Bases , Peixes-Gato/sangue , Peixes-Gato/genética , DNA Complementar/genética , Feminino , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Fosfatidilinositol 3-Quinases/química , Fosfatidilinositol 3-Quinases/genética , Domínios Proteicos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos , Wortmanina
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 356-60, 2017 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30264961

RESUMO

Avalanche photodiode is widely used in laser rangefinder due to high gain characteristics, but introduces highly additive noise during the time of current's multiplication that makes laser rangefinder's SNR meet bottleneck. This paper proposes a method of designing a high SNR's graphene photodetector based on microcavity. The graphene's unique optoelectronic properties make it an ideal platform for a variety of photonic applications, such as fast lasers, optical modulators, transparent electrodes, and ultrafast photodetectors. It has been recognized internationally to have dominant advantages in photodetectors due to its high carrier mobility, gapless spectrum, and frequency-independent absorption coefficient. With the wavelength of 1.06 µm, the mechanism of light waves' transmission in the cavity and the graphehne's absorption are studied by using optical transmission matrix method and scattering matrix method; the light absorption model of the graphene photodetector based on microcavity is established. Device's final quantum efficiency reaches 91.2%, respectively reaches 0.778 A·W(-1), its full width at half maximum (FWHM) reaches 6 nm; the influence between graphene's position in the microcavity and device's absorption shows that device's absorption's peak value changes periodically with graphene's position under resonant condition, and the variety of length of microcavity does not have any influence on the peak value, but changes the graphene's position when absorption reaches peak value, on the condition that the length of microcavity is n times of half of wavelength, the number of device's absorption peak value is 2n with the variety of graphene's position, and all the peak values are symmetrical with respect to the center of microcavity, the final graphene's position is 0.402 8 mm away from the top mirror of microcavity, and the absorption reaches 94%, Compared with single layer graphene, the absorption rate increases 16 dB; By solving SNR equation of the graphene photodetector based on microcavity and SNR equation of the avalanche photodiode, eventually finds that the SNR of the graphene photodetector based on microcavity is 90.3, which raises 10 dB compared with the avalanche photodiode's. Theoretical analysis shows the graphene photodetector based on microcavity has high absorption rate, high quantum efficiency, and high SNR. In this paper, the research achievements provide a theoretical reference to update and design higher SNR photodetector used in laser rangefinder's receiving system.

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