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1.
Mar Biotechnol (NY) ; 26(1): 28-36, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38165638

RESUMO

The aim of this study was to evaluate the effect of brown fishmeal in replacement of white fishmeal in the diet of Chinese soft-shelled turtles and to find the optimal amount of brown fishmeal to add. Five experimental groups were set up and fed to animals, and they were composed by different proportions of white and brown fishmeal: G1 (30% white and 25% brown fishmeal), G2 (25% white and 30% brown fishmeal), G3 (20% white and 35% brown fishmeal), G4 (15% white and 40% brown fishmeal), G5 (10% white and 45% brown fishmeal). G1 is regarded as the control group. Turtles were randomly divided into five experimental groups with four replicates each. The experiment lasted 72 days. The results showed that the WGR, SGR, FCR, and HSI of the G3 group were not significantly different from those of the control group (P > 0.05). In addition, brown fishmeal can increase the crude protein content in the muscles of them. Among the serum biochemical indices, there was no significant difference between the G3 group and the G1 group, except for the level of TG (P > 0.05). Meanwhile, the activities of AST, ALT, and CAT in the liver of the G3 group did not differ significantly from those of the G1 group (P > 0.05). However, the activities of ACP, AKP, and T-AOC were significantly decreased in the G3 group (P < 0.05). In addition, the alteration of fishmeal did not affect the digestive enzyme activities in the stomach, liver, and intestine, and there is no significant difference (P > 0.05). Importantly, with increasing brown fishmeal addition, the expression of Fas, Pparγ, Scd, and Stat3 showed a significant increase, while the expression of Bmp4 decreased significantly (P < 0.05). In this study, the addition of 20% white fishmeal and 35% brown fishmeal to the diet of Chinese soft-shelled turtles did not adversely affect growth performance. Therefore, 20% white fishmeal and 35% brown fishmeal are the most practical feed formulations for Chinese soft-shelled turtles in this study.


Assuntos
Tartarugas , Animais , Tartarugas/metabolismo , Metabolismo dos Lipídeos , Músculos/metabolismo , Fígado/metabolismo
2.
Fish Shellfish Immunol ; 131: 891-897, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36334700

RESUMO

This study aimed to investigate the effects of dietary Bovine lactoferricin (LFcinB) on the growth performance and non-specific immunity in Macrobrachium rosenbergii. Five experimental diets were 1.0‰ Bovine lactoferricin (LCB1); 1.5‰ Bovine lactoferricin (LCB1.5); 2.0‰ Bovine lactoferricin (LCB2); 2.5‰ Bovine lactoferricin (LCB2.5); the control group, basal diet without Bovine lactoferricin. A total of 600 prawns were randomly assigned to 5 groups in triplicate in 15 tanks for an 8-week feeding trial. The results showed the final weight, weight gain rate, specific growth rate and survival rate of prawns in the treatment groups were significantly improved versus the control (P < 0.05). The feed conversion ratio was reduced significantly in treatment groups compared to the control (P < 0.05). Compared with the control, alkaline phosphatase (AKP), acid phosphatase (ACP), lysozyme (LZM), catalase (CAT), superoxide dismutase (SOD) activities in the hepatopancreas of the treatment groups were significantly enhanced, and malondialdehyde (MDA) content was reduced significantly (P < 0.05). Compared with the control, the relative expression levels of AKP, ACP, LZM, CAT, SOD, Hsp70, peroxiredoxin-5, Toll, dorsal and relish genes were significantly higher among treatment groups, except for the AKP gene in the LCB1 group and the Hsp70 gene in the LCB1.5 group (P < 0.05). Compared with the control, the relative expression levels of TOR, 4E-BP, eIF4E1α and eIF4E2 genes were significantly enhanced in the LCB1.5 group (P < 0.05). When resistance against Vibrio parahaemolyticus in prawn is considered, higher doses of Bovine lactoferricin show better antibacterial ability. The present study indicated that dietary Bovine lactoferricin could significantly improve the growth performance and improve the antioxidative status of M. rosenbergii. The suitable addition level is 1.5 g/kg. LFcinB has great potential as a new feed additive without the threat of drug resistance.


Assuntos
Palaemonidae , Animais , Água Doce , Superóxido Dismutase/farmacologia , Imunidade Inata
3.
Fish Shellfish Immunol ; 123: 282-289, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35306176

RESUMO

The present study evaluated the growth performance, digestive enzyme activity, non-specific immunity, immunity and growth genes in Penaeus vannamei fed diets supplemented with Bovine lactoferricin (the basal diet without Bovine lactoferricin, the control; 1.0‰ Bovine lactoferricin,LCB1; 1.5‰ Bovine lactoferricin,LCB1.5; 2.0‰ Bovine lactoferricin, LCB2; 2.5‰ Bovine lactoferricin, LCB2.5) for 56 days. The feeding trial showed that the final weight, weight gain rate, and specific growth rate of the shrimp were improved significantly, while the feed conversion ratio was reduced significantly in the LCB1.5 group compared to the control (P < 0.05). The challenge test of Vibrio parahaemolyticus showed that the cumulative mortalities of shrimp in the LCB1.5, LCB2 and LCB2.5 groups were significantly lower than that in the control (P < 0.05). Compared with the control, Lipase and Trypsin activities in the hepatopancreas of LCB1.5 and LCB2 groups were significantly enhanced (P < 0.05). Compared with the control, alkaline phosphatase, acid phosphatase activities in the hepatopancreas and the relative expression levels of Relish, Toll, JAK, STAT, TOR, Raptor, 4E-BP, eIF4E1α, eIF4E2 genes in the hepatopancreas of LCB1.5, LCB2 and LCB2.5 groups were all significantly enhanced (P < 0.05). These results suggested that dietary Bovine lactoferricin could improve the growth performance, digestive capacity and immune responses of shrimp. When resistance against Vibrio parahaemolyticus in shrimp is considered, high dosage of Bovine lactoferricin showed a better effect than low dosage of Bovine lactoferricin. However, high dosage of Bovine lactoferricin can have a negative impact on the growth performance of shrimp. Considering collectively the above, Bovine lactoferricin could improve the growth performance, digestive enzymes activities, immune responses and disease resistance of P. vannamei.


Assuntos
Penaeidae , Vibrio parahaemolyticus , Ração Animal/análise , Animais , Dieta/veterinária , Resistência à Doença , Imunidade Inata , Lactoferrina , Vibrio parahaemolyticus/fisiologia
4.
J Int Med Res ; 49(11): 3000605211061040, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34851763

RESUMO

OBJECTIVE: This study aimed to investigate the type and frequency of mutations in 10 genes in 85 colorectal cancer (CRC) patients in Huizhou and the guiding significance of targeted drug use. METHODS: The 10-gene panel next-generation sequencing (NGS) was used to assess genetic variants in 85 CRC patients from the Huizhou area combined with clinical information for a comprehensive analysis. RESULTS: Upon initial mutation testing, 68% (58/85) were positive. The mutation frequencies of these genes, including KRAS, PIK3CA, NRAS, ERBB2, BRAF, EGFR, and PDGFRA, were 51%, 20%, 5%, 4%, 4%, 1%, and 1%, respectively. Overall, 29 mutation types were detected from seven genes. More mutations were detected in more advanced cancers. There were three samples with multiple mutations of a single gene, including KRAS (n = 2) and ERBB2 (n = 2), 12 samples with multiple mutations of double genes, including KRAS/PIK3CA (n = 10), BRAF/PIK3CA (n = 1), and NRAS/PIK3CA (n = 1), and one sample with multiple mutations of three genes, including ERBB2/KRAS/PIK3CA (n = 1). Theoretically, 27 patients could receive targeted treatment. During the actual treatment, 10 patients received bevacizumab, cetuximab, or fruquintinib with no progression ranging from 12 to 24 months. CONCLUSION: Gene mutations detected by a 10-gene panel were useful for targeting therapy of CRC in Huizhou.


Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas B-raf , Cetuximab , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Análise Mutacional de DNA , Humanos , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética
5.
Nanoscale ; 9(38): 14467-14475, 2017 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-28926077

RESUMO

A bimetallic CoCu alloy thin-film catalyst is developed that enables the growth of uniform, high-quality graphene at 750 °C in 3 min by chemical vapour deposition. The growth outcome is found to vary significantly as the Cu concentration is varied, with ∼1 at% Cu added to Co yielding complete coverage single-layer graphene growth for the conditions used. The suppression of multilayer formation is attributable to Cu decoration of high reactivity sites on the Co surface which otherwise serve as preferential nucleation sites for multilayer graphene. X-ray photoemission spectroscopy shows that Co and Cu form an alloy at high temperatures, which has a drastically lower carbon solubility, as determined by using the calculated Co-Cu-C ternary phase diagram. Raman spectroscopy confirms the high quality (ID/IG < 0.05) and spatial uniformity of the single-layer graphene. The rational design of a bimetallic catalyst highlights the potential of catalyst alloying for producing two-dimensional materials with tailored properties.

6.
Nanoscale ; 8(36): 16427-16434, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27722630

RESUMO

The domain boundaries of polycrystalline graphene produced by chemical vapor deposition (CVD) adversely influence the graphene transporting properties. The existing domain visualisation methods for large area graphene always cause detrimental damage or contamination. Here we report a nondestructive method for spatial visualisation of the domains and boundaries of large area continuous graphene grown on Cu foils (Gr/Cu) by CVD. Using a rationally modified optical microscope, we can directly observe novel star-like bright line sets of Gr/Cu in an enhanced dark field mode. Each set of the bright lines is identified as the ridges of one Cu surface pyramid which arises beneath one enlarging graphene domain due to slower evaporation of graphene-covered Cu than that of graphene-free Cu. This one to one correspondence thereby enables nondestructive visualisation. This method offers an advantageous pathway for monitoring the spatial distribution of the graphene domains and boundaries. We have further discovered for the first time various types of star-like ridge structures which are governed by the underlying Cu crystallographic orientations. This gives rise to a new phenomenon for research on the complex 2D material-metal interfacing.

7.
Sci Rep ; 6: 21152, 2016 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-26883292

RESUMO

We demonstrate the growth of continuous monolayer graphene films with millimeter-sized domains on Cu foils under intrinsically safe, atmospheric pressure growth conditions, suitable for application in roll-to-roll reactors. Previous attempts to grow large domains in graphene have been limited to isolated graphene single crystals rather than as part of an industrially useable continuous film. With both appropriate pre-treatment of the Cu and optimization of the CH4 supply, we show that it is possible to grow continuous films of monolayer graphene with millimeter scale domains within 80 min by chemical vapour deposition. The films are grown under industrially safe conditions, i.e., the flammable gases (H2 and CH4) are diluted to well below their lower explosive limit. The high quality, spatial uniformity, and low density of domain boundaries are demonstrated by charge carrier mobility measurements, scanning electron microscope, electron diffraction study, and Raman mapping. The hole mobility reaches as high as ~5,7002 m(2) V(-1) s(-1) in ambient conditions. The growth process of such high-quality graphene with a low H2 concentration and short growth times widens the possibility of industrial mass production.

8.
ACS Appl Mater Interfaces ; 7(6): 3626-32, 2015 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-25611675

RESUMO

We have systematically studied the macroscopic adhesive properties of vertically aligned nanotube arrays with various packing density and roughness. Using a tensile setup in shear and normal adhesion, we find that there exists a maximum packing density for nanotube arrays to have adhesive properties. Too highly packed tubes do not offer intertube space for tube bending and side-wall contact to surfaces, thus exhibiting no adhesive properties. Likewise, we also show that the surface roughness of the arrays strongly influences the adhesion properties and the reusability of the tubes. Increasing the surface roughness of the array strengthens the adhesion in the normal direction, but weakens it in the shear direction. Altogether, these results allow progress toward mimicking the gecko's vertical mobility.


Assuntos
Adesivos/química , Materiais Biomiméticos/química , Nanotubos de Carbono/química , Adesividade , Animais , Biomimética , Lagartos
9.
OMICS ; 18(2): 98-110, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24380445

RESUMO

High-throughput sequencing technologies, also known as next-generation sequencing (NGS) technologies, have revolutionized the way that genomic research is advancing. In addition to the static genome, these state-of-art technologies have been recently exploited to analyze the dynamic transcriptome, and the resulting technology is termed RNA sequencing (RNA-seq). RNA-seq is free from many limitations of other transcriptomic approaches, such as microarray and tag-based sequencing method. Although RNA-seq has only been available for a short time, studies using this method have completely changed our perspective of the breadth and depth of eukaryotic transcriptomes. In terms of the transcriptomics of teleost fishes, both model and non-model species have benefited from the RNA-seq approach and have undergone tremendous advances in the past several years. RNA-seq has helped not only in mapping and annotating fish transcriptome but also in our understanding of many biological processes in fish, such as development, adaptive evolution, host immune response, and stress response. In this review, we first provide an overview of each step of RNA-seq from library construction to the bioinformatic analysis of the data. We then summarize and discuss the recent biological insights obtained from the RNA-seq studies in a variety of fish species.


Assuntos
Peixes/genética , Genoma , Sequenciamento de Nucleotídeos em Larga Escala/métodos , RNA/química , Análise de Sequência de RNA , Transcriptoma , Animais , Perfilação da Expressão Gênica , Biblioteca Gênica , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Anotação de Sequência Molecular , Polimorfismo de Nucleotídeo Único , RNA/genética
10.
ACS Nano ; 6(4): 2893-903, 2012 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-22439978

RESUMO

We have grown vertically aligned single-walled carbon nanotube forests with an area density of 1.5 × 10(13) cm(-2), the highest yet achieved, by reducing the average diameter of the nanotubes. We use a nanolaminate Fe-Al(2)O(3) catalyst design consisting of three layers of Al(2)O(3), Fe, and Al(2)O(3), in which the lower Al(2)O(3) layer is densified by an oxygen plasma treatment to increase its diffusion barrier properties, to allow a thinner catalyst layer to be used. This high nanotube density is desirable for using carbon nanotubes as interconnects in integrated circuits.

11.
Fish Physiol Biochem ; 37(3): 453-60, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21063906

RESUMO

The molecular regulation of the trypsin activity and the effects of corn gluten meal (CGM) on the trypsin activity and gene expression in Fugu obscurus were examined. The fish were fed with diets containing 0, 50, 100, 150, and 200 g kg⁻¹ CGM for 60 days. The trypsin activity and mRNA levels in the intestine, stomach, and hepatopancreas were measured before and after the experimental feeding. Enzyme activity was highest in the intestine, and mRNA expression was highest in the hepatopancreas prior to feeding the experimental diets. The effect of dietary CGM on the trypsin activity was dependent on the concentration. Enzyme activity was significantly lower in the hepatopancreas and stomach of the 200 g kg⁻¹ treatment group than in control group. In contrast, activity was enhanced in the stomach of the 100 g kg⁻¹ treatment group. Different amounts of CGM in the diets also resulted in significant changes in the trypsin mRNA levels in all three tissues. The trypsin mRNA expression in stomach, hepatopancreas, and intestine increased with increasing CGM from 0 to 10% and decreased with increasing CGM from 10 to 20%. The trypsin mRNA expression was highest in the 100 g kg⁻¹ treatment group, which was significantly higher than that of in the control. In addition, the changes in the trypsin mRNA expression levels were not reflected by changes in the trypsin activity. Our results suggest that the trypsin activity is regulated not only at the transcription level but also during translation and posttranslational modification.


Assuntos
Ração Animal/análise , Dieta/veterinária , RNA Mensageiro/metabolismo , Takifugu/metabolismo , Tripsina/metabolismo , Zea mays/química , Fenômenos Fisiológicos da Nutrição Animal , Animais , Relação Dose-Resposta a Droga , Mucosa Gástrica/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , RNA Mensageiro/genética , Estômago/efeitos dos fármacos , Tripsina/genética
12.
Nanotechnology ; 21(48): 485301, 2010 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-21051802

RESUMO

Here we demonstrate a novel technique to grow carbon nanotubes (CNTs) on addressable localized areas, at wafer level, on a fully processed CMOS substrate. The CNTs were grown using tungsten micro-heaters (local growth technique) at elevated temperature on wafer scale by connecting adjacent micro-heaters through metal tracks in the scribe lane. The electrical and optical characterization show that the CNTs are identical and reproducible. We believe this wafer level integration of CNTs with CMOS circuitry enables the low-cost mass production of CNT sensors, such as chemical sensors.

13.
ACS Nano ; 3(11): 3560-6, 2009 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-19877596

RESUMO

We present a systematic study of the temperature and pressure dependence of the growth rate of vertically aligned small diameter (single- and few-walled) carbon nanotube forests grown by thermal chemical vapor deposition over the temperature range 560-800 degrees C and 10(-5) to 14 mbar partial pressure range, using acetylene as the feedstock and Al(2)O(3)-supported Fe nanoparticles as the catalyst. We observe a pressure dependence of P(0.6) and activation energies of <1 eV. We interpret this as a growth rate limited by carbon diffusion in the catalyst, preceded by a pre-equilibrium of acetylene dissociation on the catalyst surface. The carbon nanotube forest growth was recorded by high-resolution real-time optical imaging.

14.
ACS Nano ; 3(6): 1557-63, 2009 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-19462964

RESUMO

We investigate the long-standing question of whether electrons accelerated at 80 kV are below the knock-on damage threshold for single-walled carbon nanotubes (SWNTs). Aberration-corrected high-resolution transmission electron microscopy is used to directly image the atomic structure of the SWNTs and provides in situ monitoring of the structural modification induced by electron beam irradiation at 80 kV. We find that SWNTs with small diameters of 1 nm are damaged by the electron beam, and defects are produced in the side walls that can lead to their destruction. SWNTs with diameters of 1.3 nm and larger are more stable against degradation, and stability increases with diameter. The effect of diameter, defects, and exterior contamination on the inherent stability of SWNTs under electron beam irradiation is investigated.

15.
J Phys Chem B ; 111(8): 1907-10, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17279793

RESUMO

Half-centimeter-high mats of vertically aligned single-walled carbon nanotubes were grown at 600 degrees C by point-arc microwave plasma chemical vapor deposition. The mats were produced from 0.5 nm of an Fe catalyst layer, thus showing one of the highest catalytic yields of approximately 105 times. The growth process shows a lack of poisoning of the catalyst, in contrast to other reports. The experimental results confirm that the growth rate is ultimately limited by the gas phase diffusion of hydrocarbon radicals.

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