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1.
Oncologist ; 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32058619

RESUMO

LESSONS LEARNED: Administration of lapatinib with food significantly increased its plasma concentration in Chinese patients with metastatic breast cancer. There were no serious adverse events during the study and no significant differences in lapatinib-related adverse events between the fasted and fed states. BACKGROUND: Lapatinib, a small molecular reversible dual tyrosine kinase inhibitor of epidermal growth factor receptor (EGFR) and human epidermal growth receptor 2 (HER2), was approved for use in combination with capecitabine to treat metastatic HER2-positive breast cancer. Administration of lapatinib in the fasted state was recommended; however, our preliminary phase II trial data showed that administration of lapatinib with food increased its concentration. METHODS: This study was a single-center, open-label, and prospective self-controlled clinical study. Ten Chinese patients with metastatic breast cancer were enrolled from June 2017 to April 2018. They were required to receive lapatinib plus physician's choice of chemotherapy. Patients were required to take lapatinib orally on an empty stomach continually for 10 days, and then take lapatinib with food continually for the next 10 days. Plasma concentration was measured by liquid chromatography on the 9th and 10th day of each state. RESULTS: Area under the concentration-time curve (AUC) of the fasted state and the fed state was 21.23 ± 8.91 mg*h/L (Coefficient of variation (CV)% 42%) and 60.60 ± 16.64 mg*h/L (CV% 27%), respectively. The mean plasma concentration in the fasted state was 0.88 ± 0.39 mg/L (CV% 45%), and that in the fed state was 2.53 ± 0.77 mg/L (CV% 30%). Compared with taking lapatinib on an empty stomach, receiving lapatinib with food significantly increased the plasma concentration of lapatinib (Wilcoxon match-paired test, p = .005). In addition, there were no serious adverse events during the study or significant difference in lapatinib-related adverse events between the two states. CONCLUSION: Our study shows that receiving lapatinib with food can increase its plasma concentration with no significantly increased drug-related toxicity. We suggest that a larger-sample-size clinical trial is needed to fully understand the effect of administration of lapatinib with food.

2.
J Hazard Mater ; 389: 122117, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31978821

RESUMO

Coconut-fiber biochar (CFB) was applied at 3% (w/w) to two soils spiked with 250, 2500, 5000 mg kg-1 of lead (Pb), respectively, aiming to explore the effects of CFB and the significance of iron (Fe) plaque on rice roots on the accumulation and translocation of Pb in rice plants using micro-X-ray fluorescence and X-ray absorption spectroscopies. The CFB amendment resulted in a significant decrease in the EDTA-extractable Pb availability in the soils, which might be attributed to the increased amounts of Pb-loaded humic acid and Pb3(PO4)2 formed in the soils. Consequently, the addition of CFB caused a significant decrease in Pb concentrations of the brown rice harvested from the CFB-amended soils under all Pb levels by 14 %-47 %, as compared to those from the unamended soils. Therefore, CFB could be used as an immobilizing agent for Pb in contaminated soils. However, CFB application significantly inhibited the formation of Fe/Mn plaques on rice roots and reduced its interception effect on Pb uptake, which consequently increased the Pb translocation rate from root to shoot. Therefore, the increased translocation rate of Pb in rice plants by CFB should not be ignored when CFB is applied to remediate Pb-contaminated paddy soils.

3.
Oncologist ; 25(1): 21-e15, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31434793

RESUMO

LESSONS LEARNED: Studies targeting the androgen receptor (AR) signaling pathway in aromatase inhibitor (AI)-resistant breast cancer are limited. Bicalutamide, one of the commonly used AR inhibitors in prostate cancer, in combination with AI, did not show synergistic activity in patients with estrogen receptor-positive and AI-resistant disease in this phase II, single-arm study. The clinical benefit rate and objective response rate at 6 months were 16.7% and 0%, respectively, and the study was terminated after the first stage. BACKGROUND: Endocrine resistance is a major problem in clinical practice. Studies have shown that androgen receptor (AR) signaling activation may be one of the mechanisms, and targeting AR showed some promising results in AR-positive triple-negative breast cancer. The aim of this study was to assess the efficacy and safety of bicalutamide plus another aromatase inhibitor in patients with nonsteroidal aromatase inhibitor (AI) or steroidal AI resistance and estrogen receptor (ER)-positive and AR-positive advanced breast cancer. METHODS: A Simon's two-stage, phase II, single-arm study was conducted. We assumed the clinical benefit rate (CBR) of 40% would be significant in clinical practice. In this case, if ≥4 patients of the 19 patients in the first stage benefited from treatment, the CBR would achieve the assumed endpoint. If fewer than four patients benefited from treatment in the first stage, the trial would be terminated. All patients received bicalutamide 50 mg per day orally plus another aromatase inhibitor. The primary outcome was CBR; secondary outcomes included objective response rate (ORR), progression-free survival (PFS), and tolerability. RESULTS: A total of 19 patients enrolled in the first stage, and 18 patients met all criteria for analysis. The trial terminated according to protocol after the first stage. After a median follow-up of 14 months, the CBR at 6 months was 16.7% (3/18); no patients with partial or complete response were observed. The median PFS was 2.7 months. Bicalutamide in combination with AI was well tolerated. CONCLUSION: Bicalutamide in combination with another AI did not show synergistic activity in patients with ER-positive breast cancer and AI resistance. Results suggest that no more large-sample clinical trials should be conducted in this population for overcoming endocrine resistance.

4.
Anim Biotechnol ; : 1-9, 2019 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-31680615

RESUMO

Aquaporin 9 plays critical roles in aspects of energy homeostasis, metabolism, gluconeogenesis, fat synthesis and even the individual growth and development. So the Aquaporin 9 (AQP9) gene is a potential candidate gene for bovine growth traits. In this study, we detected the polymorphism of the bovine AQP9 gene including all exons by PCR-SSCP and DNA sequencing methods with six pairs of PCR primers in 555 individuals from three cattle breeds. Three novel SNPs (NC_007308:g.47575 C > T, 47615 C > T, 47690A > G) were detected using P6 primer. The linkage disequilibrium analysis indicated that the three SNPs were completely linked (r2 = 1), which constructed three genotypes (AA, AB, BB). The genotype AB was dominant in all three breeds. The frequencies of haplotype A and haplotype B were almost equivalent between each other. The individuals with genotype AB were significantly higher than those individuals with genotype BB in body weight (p < 0.01), chest circumference (p < 0.05) and rump length (p < 0.05). Moreover, individuals with genotype AA were significantly higher than those of individuals with genotype BB in body height (p < 0.01). These results suggested that the novel SNPs could be a perfect molecular marker for marker-assisted selection (MAS) breeding.

5.
Sci Adv ; 5(11): eaav4355, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31700996

RESUMO

Recently, several captivating topological structures of electric dipole moments (e.g., vortex, flux closure) have been reported in ferroelectrics with reduced size/dimensions. However, accurate polarization distribution of these topological ferroelectric structures has never been experimentally obtained. We precisely measure the polarization distribution of an individual ferroelectric vortex in PbTiO3/SrTiO3 superlattices at the subunit cell level by using the atomically resolved integrated differential phase contrast imaging in an aberration-corrected scanning transmission electron microscope. We find, in vortices, that out-of-plane polarization is larger than in-plane polarization, and that downward polarization is larger than upward polarization. The polarization magnitude is closely related to tetragonality. Moreover, the contribution of the Pb─O bond to total polarization is highly inhomogeneous in vortices. Our precise measurement at the subunit cell scale provides a sound foundation for mechanistic understanding of the structure and properties of a ferroelectric vortex and lattice-charge coupling phenomena in these topological ferroelectric structures.

6.
Eur J Pharmacol ; 863: 172669, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31542486

RESUMO

The antiresorptive agents still are the mainstay of osteoporosis treatment. This study aimed to investigate the efficacy of recombinant Lingzhi-8 (rLZ-8) on osteoclast in vitro and bone resorption in vivo. The rLZ-8 protein was derived from Ganoderma lucidum transformation and produced by a genetic system. Receptor activator of nuclear factor kappa-Β ligand induced RAW 264.7 cells to differentiate into osteoclastic cells in vitro. Cells were exposed to different doses of rLZ-8 for 7 days to measure differences of osteoclastic differentiation, apoptosis rate and gene expression. rLZ-8 was labeled with Alexa Fluor 568 to observe its intracellular distribution under super-resolution light microscopy. In addition, retinoic acid was administered to female rats for 14 days to develop osteopenia changes. Different doses of rLZ-8 were simultaneously administered to rats treated with retinoic acid to observe changes of bone mineral density, biochemical parameters and organ weight ratio. Results indicated that rLZ-8 regulated receptor activator of nuclear factor kappa-Β (RANK) - tumor necrosis factor receptor-associated factor 6 (TRAF6) - c-Jun N-terminal kinase (JNK) signaling pathway, by which rLZ-8 inhibited osteoclastic differentiation and promoted osteoclastic apoptosis. Through 3D-structured illumination microscopy, it was observed that rLZ-8 entered RAW264.7 cells and accumulated gradually into the cytoplasm but little into nucleus. Administration with rLZ-8 reversed loss of bone mass and improved ALP activity in osteoporotic rats. Low-to high-dose rLZ-8 treatments displayed little toxic effects on rat organs and did not seem to impact their overall health. All data suggested that rLZ-8 has possible action against osteoporosis.

7.
PLoS One ; 14(9): e0222353, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31532787

RESUMO

Menopause is an endocrine-related transition that induces a number of physiological and potentially pathological changes in middle-aged and elderly women. The intention of this research was to investigate the influence of menopause on the intricate relationships between major biochemical metabolites. The study involved metabolic profiling of 186 metabolic markers measured in blood plasma collected from 120 healthy female participants. We developed a method of network analysis using differential correlation that enabled us to detect and characterize differences in metabolites and changes in inter-relationships in pre- and post-menopausal women. A topological analysis was performed on the differential network that uncovered metabolite differences in pre-and post-menopausal women. In this analysis, our method identified two key metabolites, sphingomyelins and phosphatidylcholines, which may be useful in directing further studies into menopause-specific differences in the metabolome, and how these differences may underlie the body's response to stress and disease following the transition from pre- to post-menopausal status for women.

8.
Huan Jing Ke Xue ; 40(5): 2460-2470, 2019 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087888

RESUMO

In order to evaluate the potential agricultural risks of soil contaminated by polycyclic aromatic hydrocarbons (PAHs), Lactuca sativa L. was used as a model leaf vegetable plant to investigate the enrichment characteristics of PAHs in the different tissues of Lactuca sativa L, such as its underground parts (GS) and aboveground parts (YS), which were studied through an experiment involving potted cultivation in PAHs contaminated soil that was taken from the agricultural soil around a coking enterprise area. The concentrations of the different PAHs in the soil and plant tissues were analyzed using ultrasonic oscillation extraction and high-performance liquid chromatography-mass spectrometry (GC-MS) analysis methods. The results show that the enrichment of the total PAHs (Σ16PAHs) in the YS is higher than that in the GS. The components enriched in the YS mainly consist of 3-5 ring PAHs, and those in the GS consist of 4-6ring PAHs. The coefficients of the different PAHs enriched in the YS were higher than those of the GS. The enrichment coefficient of anthracene (Ant) was the largest and that of fluoranthene (Fla) was the smallest in the YS, while the enrichment coefficient of benzene[a]pyre (Bap) was the largest and that of Fla was the smallest in the GS. The transfer coefficients of the different PAHs from the GS to the YS were greater than the rate from the initial soil (SS) to the GS; the value is less than 1 from the SS to GS. The correlations and goodness of fit were analyzed for the concentrations of PAHs in the SS, GS and YS. The Σ16PAHs in the SS showed positive correlations with the Σ16PAHs in the YS and in GS. The goodness of fit of the correlation of the PAHs in YS to those in the SS was the largest (R2=1.0), while the goodness-of-fit for the correlation between the GS and SS was lower (R2=0.71). The benzo[a]pyrene equivalent concentration values (Σ16PAHsBapeq) of YS and GS were 11.8 and 12.7 times the maximum value of Bap level allowed in food. The study indicates that contaminated farmland soil would present a high health risk when it was used to grow the plant.


Assuntos
Alface/crescimento & desenvolvimento , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Agricultura , Medição de Risco , Solo
9.
ACS Appl Mater Interfaces ; 11(14): 13251-13256, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30874420

RESUMO

Silicon is now well-recognized to be a promising alternative anode for advanced lithium-ion batteries because of its highest capacity available today; however, its insufficiently high Coulombic efficiency upon cycling remains a major challenge for practical application. To overcome this challenge, we have developed a facile mechanochemical method to synthesize a core-shell-structured Si/polyphenylene composite (Si/PPP) with a n-type conductive PPP layer tightly bonded in a planar orientation to the surfaces of Si nanocores. Because of its compactness and flexibility, the outer PPP layer can protect the Si core from contacting the electrolyte and maintaining the structural stability of electrode/electrolyte interface during cycles. As a result, the Si/PPP anode demonstrated a high reversible capacity of ∼2387 mAh g-1, a stable cycleability with 88.5% capacity retention over 500 cycles, and, particularly, a high Coulombic efficiency of 99.7% upon extended cycling, offering a new insight for future development of high-capacity and cycle-stable Si anode.

10.
Biol Trace Elem Res ; 187(2): 492-498, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29770951

RESUMO

Research focused on transforming growth factor ß (TGFß) signaling in osteoblast is gradually increasing, whereas literature is rare in terms of fluorosis. This work aimed to investigate how TGFß signaling participated in regulation of the osteoblast by different doses of fluoride treatment. Bone marrow stem cells (BMSCs) were developed into osteoblastic cells and exposed to 1, 4, and 16 mg/L F- with and without 10 ng/mL of TGFß. Cell viability and differentiation state of osteoblast under different settings were measured by means of cell counting kit and analysis of alkaline phosphatase (ALP) activity as well as formation of mineral nodules. Real-time PCR was utilized to test expression of ALP and Runt-related transcription factor 2 (Runx2) at gene level. The gene expression of TGFß signaling effectors was also investigated, such as TGFß receptors (TßRs), smad3, and mitogen-activated protein kinases (MAPK). Results demonstrated that fluoride treatment exhibited action on osteoblast viability and osteogenic differentiation and upregulated expression of TßR2, smad3, and MAPK in this process. Administration of TGFß strengthened ALP activity but attenuated formation of mineral nodules. Co-treatment of TGFß and low-dose fluoride increased ALP activity compared to same dose of single fluoride treatment, whereas it inhibited mineral nodule formation. Administration of TGFß reversed the suppression of high-dose fluoride on osteogenic differentiation of BMSCs. Taken together, studies revealed that TßR2 acted as a target for fluoride and TGFß treatment on BMSCs, and smad3 and MAPK were involved in the mechanism of fluoride regulating osteogenic differentiation. Together, our data indicated that TGFß receptor-mediated signaling through smad3 and MAPK was required for modulation of fluoride on osteoblast viability and differentiation, and activating TßR2-smad3 signaling pathway reversed suppression of osteoblasts differentiation by high dose of fluoride treatment.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Fluoretos/farmacologia , Osteoblastos/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Masculino , Camundongos , Camundongos Endogâmicos , Osteoblastos/metabolismo , Osteogênese/efeitos dos fármacos , Fator de Crescimento Transformador beta/administração & dosagem , Fator de Crescimento Transformador beta/genética
11.
Free Radic Biol Med ; 131: 251-263, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30502455

RESUMO

Cerebral ischemia induces neuronal cell death in different ways and mitochondrial dysfunction is an important cause. Astragaloside IV (AIV) is a natural saponin abandent in Astragalus membranaceus and this study aims to find if AIV protects neuronal survival via preserving mitochondrial hexokinase-II (HK-II). Glutamate stimulation induced HK-II dissociation from mitochondria and impaired mitochondrial function, indicated by the opening of the mitochondrial permeability transition pore, the collapse of mitochondrial membrane potential and reduced mitochondrial oxygen consumption ratio in neurons. Accompanied with apoptosis, oxidative DNA damage, PAR formation and nuclear translocation of apoptosis inducing factor (AIF) indicated the presence of parthanatos. AIV activated Akt and protected mitochondrial HK-II via promoting the binding of Akt to HK-II and protected hexokinase activity with improved glycolysis. As a consequence of preserved mitochondrial HK-II, AIV reduced the release of pro-apoptotic proteins and AIF, resultantly protected neurons from apoptosis and parthanatos. Moreover, the neuroprotective effects of AIV were also reproduced in mice subjected to middle cerebral artery occlusion to support the findings in vitro. Together, these results showed that glutamate excitotoxicity impaired mitochondrial HK-II and simultaneously induced apoptosis and parthanatos owing to mitochondrial dysfunction. AIV activated Akt to promote HK-II binding to mitochondria, and the structural and functional integrity of mitochondria contributed to protecting neurons from apoptosis and DNA damage. These findings address the important role of mitochondrial HK-II in neuronal protection.


Assuntos
Astragalus propinquus/química , Hexoquinase/genética , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Saponinas/farmacologia , Triterpenos/farmacologia , Animais , Fator de Indução de Apoptose/genética , Fator de Indução de Apoptose/metabolismo , Feminino , Regulação da Expressão Gênica , Ácido Glutâmico/farmacologia , Hexoquinase/metabolismo , Humanos , Hipóxia-Isquemia Encefálica/etiologia , Hipóxia-Isquemia Encefálica/genética , Hipóxia-Isquemia Encefálica/patologia , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/cirurgia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/isolamento & purificação , Consumo de Oxigênio/efeitos dos fármacos , /genética , Cultura Primária de Células , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Saponinas/isolamento & purificação , Triterpenos/isolamento & purificação
12.
Braz J Infect Dis ; 22(6): 477-486, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30586543

RESUMO

Antiviral drug resistance is the most important factor contributing to treatment failure using nucleos(t)ide analogs such as lamivudine for chronic infection with hepatitis B virus (HBV). Development of a system supporting efficient replication of clinically resistant HBV strains is imperative, and new antiviral drugs are needed urgently to prevent selection of drug-resistant HBV mutants. A novel fluorinated cytidine analog, NCC (N-cyclopropyl-4'-azido-2'-deoxy-2'-fluoro-ß-d-cytidine), was recently shown to strongly inhibit human HBV in vitro and in vivo. This study was designed to evaluate the antiviral activity of NCC against lamivudine-resistant HBV. We generated a stable cell line encoding the major pattern of lamivudine-resistant mutations rtL180M/M204V and designated it "HepG2.RL1". Immuno-transmission electron microscopic examination and enzyme-linked immunosorbent assay were used to detect secretion of HBV-specific particles and antigens. Quantification of extracellular DNA and intracellular DNA of HepG2.RL1 cells by quantitative real-time polymerase chain reaction revealed >625-fold and >5556-fold increases in the 50% inhibitory concentration of lamivudine, respectively, compared with that for the wild-type virus. The results showed that NCC inhibited DNA replication and HBeAg production in wild-type or lamivudine-resistant HBV in a dose-dependent manner. In conclusion, screening for antiviral compounds active against lamivudine-resistant HBV can be carried out with relative ease using hepG2.RL1 cells. NCC is a potential antiviral agent against wild-type HBV and clinical lamivudine-resistant HBV and deserves evaluation for the treatment of HBV infection.

13.
Nat Commun ; 9(1): 4807, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30442950

RESUMO

Organic-inorganic hybrid perovskites are promising candidates for the next-generation solar cells. Many efforts have been made to study their structures in the search for a better mechanistic understanding to guide the materials optimization. Here, we investigate the structure instability of the single-crystalline CH3NH3PbI3 (MAPbI3) film by using transmission electron microscopy. We find that MAPbI3 is very sensitive to the electron beam illumination and rapidly decomposes into the hexagonal PbI2. We propose a decomposition pathway, initiated with the loss of iodine ions, resulting in eventual collapse of perovskite structure and its decomposition into PbI2. These findings impose important question on the interpretation of experimental data based on electron diffraction and highlight the need to circumvent material decomposition in future electron microscopy studies. The structural evolution during decomposition process also sheds light on the structure instability of organic-inorganic hybrid perovskites in solar cell applications.

14.
Braz. j. infect. dis ; 22(6): 477-486, Nov.-Dec. 2018. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-984016

RESUMO

ABSTRACT Antiviral drug resistance is the most important factor contributing to treatment failure using nucleos(t)ide analogs such as lamivudine for chronic infection with hepatitis B virus (HBV). Development of a system supporting efficient replication of clinically resistant HBV strains is imperative, and new antiviral drugs are needed urgently to prevent selection of drug-resistant HBV mutants. A novel fluorinated cytidine analog, NCC (N-cyclopropyl-4′-azido-2′-deoxy-2′-fluoro-β-d-cytidine), was recently shown to strongly inhibit human HBV in vitro and in vivo. This study was designed to evaluate the antiviral activity of NCC against lamivudine-resistant HBV. We generated a stable cell line encoding the major pattern of lamivudine-resistant mutations rtL180M/M204V and designated it "HepG2.RL1". Immuno-transmission electron microscopic examination and enzyme-linked immunosorbent assay were used to detect secretion of HBV-specific particles and antigens. Quantification of extracellular DNA and intracellular DNA of HepG2.RL1 cells by quantitative real-time polymerase chain reaction revealed >625-fold and >5556-fold increases in the 50% inhibitory concentration of lamivudine, respectively, compared with that for the wild-type virus. The results showed that NCC inhibited DNA replication and HBeAg production in wild-type or lamivudine-resistant HBV in a dose-dependent manner. In conclusion, screening for antiviral compounds active against lamivudine-resistant HBV can be carried out with relative ease using hepG2.RL1 cells. NCC is a potential antiviral agent against wild-type HBV and clinical lamivudine-resistant HBV and deserves evaluation for the treatment of HBV infection.

15.
Fish Shellfish Immunol ; 83: 158-161, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30195902

RESUMO

An eight-week experiment was conducted to determine the effects of dietary fulvic acids (FAs) on the growth performance, digestive enzymes and nonspecific immunity of red swamp crayfish Procambarus clarkia. Three diets supplemented with three different levels of FAs (0.1, 0.5 and 1 g kg-1) were formulated and tested for the growth performance, digestive enzymes and nonspecific immunity of the crayfish, and a diet without FAs served as control. After eight weeks of feeding, survival rate, phenoloxidase activity, superoxide dismutase activity, glutathione peroxidase level, total haemocyte count and number of hyaline cells, semigranular cells and granular cells and resistance to Aeromonas hydrophila of crayfishes fed with FA-containing diets were higher than those of the control. Moreover, based on the efficiency of FAs on the growth performance and nonspecific immunity of crayfish, the optimum dose of FAs was found to be 0.5 g (kg diet)-1. A high level of FA administration (1 g kg-1) did not further increase the efficiency of FAs compared with those in the moderate group (0.5 g kg-1, p > 0.05). Results indicated that oral administration of FA-containing diets can enhance the growth performance, intestinal digestive enzymes, immune responses and resistance of crayfish to infection by A. hydrophila. Thus, FAs may be utilized as a diet supplement for crayfish.


Assuntos
Astacoidea , Benzopiranos/administração & dosagem , Peso Corporal , Suplementos Nutricionais/análise , Administração Oral , Ração Animal/análise , Animais , Antioxidantes/administração & dosagem , Astacoidea/crescimento & desenvolvimento , Astacoidea/imunologia , Fenômenos Fisiológicos do Sistema Digestório , Doenças dos Peixes/imunologia , Imunidade Inata
16.
Nanoscale ; 10(39): 18492-18501, 2018 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-30132773

RESUMO

Quasi-one-dimensional semiconducting materials have attracted increasing attention due to their excellent ability to downscale the size of transistors. However, in quasi-one-dimensional nanowire (NW) transistors, their surface and interface properties play a very important role mainly due to the large surface-to-volume ratio of NWs and surface scattering, which degrade their carrier mobility. Herein, we developed a new method to cover the channel surface of InAs NW field effect transistors (FETs) with Y2O3/HfO2 layers to improve their electrical properties. We successfully fabricated nine FETs and measured their electrical properties, which improve after depositing the Y2O3/HfO2 layers, including an increase in on-state current, decrease in off-state current, increase in transconductance, increase in electron mobility and decrease in subthreshold swing. By comparing the properties of Y2O3/HfO2-covered devices with that of the FETs fabricated without the Y2O3 covering or without annealing, we prove that it is the combined Y2O3/HfO2 layers instead of only the Y2O3 or HfO2 layer that improve the electrical properties of the FETs. The Cs-corrected high-resolution scanning transmission electron microscopy study demonstrates that Y can actually diffuse through the native oxide layer (confirmed to be InOx) and reach the surface of the InAs NWs. Our results indicate that the desirable characteristics of Y2O3 and the surface passivation by HfO2 improve the electrical properties of the InAs NW FETs, in which Y2O3 plays an important role to modify and stabilize the interface between the InAs NWs and the outside dielectric layer. Furthermore, this method should also be applicable to other III-V materials.

17.
Nano Lett ; 18(9): 6094-6099, 2018 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-30142274

RESUMO

Ionic doping and migration in solids underpins a wide range of applications including lithium ion batteries, fuel cells, resistive memories, and catalysis. Here, by in situ transmission electron microscopy technique we directly track the structural evolution during Li ions insertion and extraction in transition metal dichalcogenide 1T-V1+ xSe2 nanostructures which feature spontaneous localized superstructures due to the periodical interstitial V atoms within the van der Waals interlayers. We find that lithium ion migration destroys the cationic orderings and leads to a phase transition from superstructure to nonsuperstructure. This phase transition is reversible, that is, the superstructure returns back after extraction of lithium ion from Li yV1+ xSe2. These findings provide valuable insights into understanding and controlling the structure and properties of 2D materials by general ionic and electric doping.

18.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 34(6): 826-830, 2017 Dec 10.
Artigo em Chinês | MEDLINE | ID: mdl-29188609

RESUMO

OBJECTIVE: To explore the genetic cause for two familial Angelman syndrome cases and correlation between the clinical phenotypes and their genetic basis. METHODS: Karyotyping analysis and microarray assay were carried out to exclude chromosome anomalies and uniparental disomy. The UBE3A gene was analyzed for potential point mutations, deletions, insertions and splice site mutations. Reverse transcription PCR was used to evaluate splicing mutation of the RNA transcripts. RESULTS: DNA sequencing showed the proband of family 1 has carried a novel maternal UBE3A splice acceptor site mutation, resulting in a guanine-to-cytosine transversion (IVS15-1G>C). Reverse transcription PCR revealed the proband and his mother both carried heterozygous mutant transcripts with loss of 54 and 59 nucleotides in exon 16, respectively. The proband displayed severe mental retardation, ataxia, seizures and inappropriate laughter. The siblings of family 2 has carried a novel maternal missense mutation in exon 16 of the UBE3A gene (c.2540C>T). She also presented with mental retardation, absent speech, mild ataxia and inappropriate laughter. CONCLUSION: The novel IVS15-1G>C and c.2540 C>T mutations of the UBE3A gene probably underlie the AS in the two families. Compared with small-scale mutations, larger fragments mutations can produce more severe phenotypes.


Assuntos
Síndrome de Angelman/genética , Mutação , Ubiquitina-Proteína Ligases/genética , Feminino , Humanos , Cariotipagem , Masculino
19.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 34(4): 509-513, 2017 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-28777848

RESUMO

OBJECTIVE: To explore the correlation between 13q33-q34 microdeletion and clinical phenotype. METHODS: Routine chromosomal banding was performed to analyze the karyotype, while array-based comparative genomic hybridization (aCGH array) and single nucleotide polymorphism array(SNP array) were employed to investigate the genome copy number variations. RESULTS: The karyotype of patient 1 was 46, XY, 9qh+,13qs. Patient 2 showed 46, XX, der (13). Patient 3 showed 46, XX, r(13) (p11.2q32) [43]/45, XX, 13[4]/46, XX, r(13;13) [2]/47, XX, 2r(13;13) [1]. Patient 4 did not undergo chromosome karyotyping analysis. Array analysis showed that four patients have different microdeletions in 13q33-34 region and had common features of 13q33-q34deletion including intellectual disability, facial dysmorphism, microcephaly, hypotonia, low birth weight and genital abnormality. CONCLUSION: The severity of phenotypes showed no correlation with the size of deletion in 13q33-q34. The lower percentage of patients with congenital heart disease suggested a complex pathogenesis of such disease. EFNB2, LIG4 and SOX1 in 13q33-34 region are promising candidates for mental retardation. LIG4 was also a likely candidate for microcephaly.


Assuntos
Cromossomos Humanos Par 13/genética , Deficiência Intelectual/genética , Pré-Escolar , Bandeamento Cromossômico/métodos , Deleção Cromossômica , Feminino , Testes Genéticos/métodos , Humanos , Lactente , Masculino
20.
Nat Commun ; 8: 15549, 2017 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-28585548

RESUMO

Although the size effect in ferroelectric thin films has been known for long time, the underlying mechanism is not yet fully understood and whether or not there is a critical thickness below which the ferroelectricity vanishes is still under debate. Here, we directly measure the thickness-dependent polarization in ultrathin PbZr0.2Ti0.8O3 films via quantitative annular bright field imaging. We find that the polarization is significantly suppressed for films <10-unit cells thick (∼4 nm). However, approximately the polarization never vanishes. The residual polarization is ∼16 µCcm-2 (∼17%) at 1.5-unit cells (∼0.6 nm) thick film on bare SrTiO3 and ∼22 µCcm-2 at 2-unit cells thick film on SrTiO3 with SrRuO3 electrode. The residual polarization in these ultrathin films is mainly attributed to the robust covalent Pb-O bond. Our atomic study provides new insights into mechanistic understanding of nanoscale ferroelectricity and the size effects.

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