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1.
Nat Prod Bioprospect ; 14(1): 7, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38200389

RESUMO

Metagenomics has opened new avenues for exploring the genetic potential of uncultured microorganisms, which may serve as promising sources of enzymes and natural products for industrial applications. Identifying enzymes with improved catalytic properties from the vast amount of available metagenomic data poses a significant challenge that demands the development of novel computational and functional screening tools. The catalytic properties of all enzymes are primarily dictated by their structures, which are predominantly determined by their amino acid sequences. However, this aspect has not been fully considered in the enzyme bioprospecting processes. With the accumulating number of available enzyme sequences and the increasing demand for discovering novel biocatalysts, structural and functional modeling can be employed to identify potential enzymes with novel catalytic properties. Recent efforts to discover new polysaccharide-degrading enzymes from rumen metagenome data using homology-based searches and machine learning-based models have shown significant promise. Here, we will explore various computational approaches that can be employed to screen and shortlist metagenome-derived enzymes as potential biocatalyst candidates, in conjunction with the wet lab analytical methods traditionally used for enzyme characterization.

2.
Environ Res ; 229: 115925, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37086884

RESUMO

Ruminant animals house a dense and diverse community of microorganisms in their rumen, an enlarged compartment in their stomach, which provides a supportive environment for the storage and microbial fermentation of ingested feeds dominated by plant materials. The rumen microbiota has acquired diverse and functionally overlapped enzymes for the degradation of plant cell wall polysaccharides. In rumen Bacteroidetes, enzymes involved in degradation are clustered into polysaccharide utilization loci to facilitate coordinated expression when target polysaccharides are available. Firmicutes use free enzymes and cellulosomes to degrade the polysaccharides. Fibrobacters either aggregate lignocellulose-degrading enzymes on their cell surface or release them into the extracellular medium in membrane vesicles, a mechanism that has proven extremely effective in the breakdown of recalcitrant cellulose. Based on current metagenomic analyses, rumen Bacteroidetes and Firmicutes are categorized as generalist microbes that can degrade a wide range of polysaccharides, while other members adapted toward specific polysaccharides. Particularly, there is ample evidence that Verrucomicrobia and Spirochaetes have evolved enzyme systems for the breakdown of complex polysaccharides such as xyloglucans, peptidoglycans, and pectin. It is concluded that diversity in degradation mechanisms is required to ensure that every component in feeds is efficiently degraded, which is key to harvesting maximum energy by host animals.


Assuntos
Metagenoma , Rúmen , Animais , Rúmen/metabolismo , Rúmen/microbiologia , Lignina , Bactérias/genética , Bactérias/metabolismo , Polissacarídeos/metabolismo , Bacteroidetes/genética , Bacteroidetes/metabolismo
3.
Sci Total Environ ; 866: 161066, 2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-36565882

RESUMO

Discharging the tannery wastewater into the environment is a serious challenge worldwide due to the release of severe recalcitrant pollutants such as oil compounds and organic materials. The biological treatment through enzymatic hydrolysis is a cheap and eco-friendly method for eliminating fatty substances from wastewater. In this context, lipases can be utilized for bio-treatment of wastewater in multifaceted industrial applications. To overcome the limitations in removing pollutants in the effluent, we aimed to identify a novel robust stable lipase (PersiLipase1) from metagenomic data of tannery wastewater for effective bio-degradation of the oily wastewater pollution. The lipase displayed remarkable thermostability and maintained over 81 % of its activity at 60 °C.After prolonged incubation for 35 days at 60°C, the PersiLipase1 still maintained 53.9 % of its activity. The enzyme also retained over 67 % of its activity in a wide range of pH (4.0 to 9.0). In addition, PersiLipase1 demonstrated considerable tolerance toward metal ions and organic solvents (e.g., retaining >70% activity after the addition of 100 mM of chemicals). Hydrolysis of olive oil and sheep fat by this enzyme showed 100 % efficiency. Furthermore, the PersiLipase1 proved to be efficient for biotreatment of oil and grease from tannery wastewater with the hydrolysis efficiency of 90.76 % ± 0.88. These results demonstrated that the metagenome-derived PersiLipase1 from tannery wastewater has a promising potential for the biodegradation and management of oily wastewater pollution.


Assuntos
Lipase , Águas Residuárias , Animais , Ovinos , Lipase/química , Hidrólise , Detergentes , Solventes/química , Concentração de Íons de Hidrogênio , Temperatura
4.
Genome Res ; 2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35948368

RESUMO

Understanding the genetic mechanisms of phenotypic variation in hybrids between domestic animals and their wild relatives may aid germplasm innovation. Here, we report the high-quality genome assemblies of a male Pamir argali (O ammon polii, 2n = 56), a female Tibetan sheep (O aries, 2n = 54), and a male hybrid of Pamir argali and domestic sheep, and the high-throughput sequencing of 425 ovine animals, including the hybrids of argali and domestic sheep. We detected genomic synteny between Chromosome 2 of sheep and two acrocentric chromosomes of argali. We revealed consistent satellite repeats around the chromosome breakpoints, which could have resulted in chromosome fusion. We observed many more hybrids with karyotype 2n = 54 than with 2n = 55, which could be explained by the selfish centromeres, the possible decreased rate of normal/balanced sperm, and the increased incidence of early pregnancy loss in the aneuploid ewes or rams. We identified genes and variants associated with important morphological and production traits (e.g., body weight, cannon circumference, hip height, and tail length) that show significant variations. We revealed a strong selective signature at the mutation (c.334C > A, p.G112W) in TBXT and confirmed its association with tail length among sheep populations of wide geographic and genetic origins. We produced an intercross population of 110 F2 offspring with varied number of vertebrae and validated the causal mutation by whole-genome association analysis. We verified its function using CRISPR-Cas9 genome editing. Our results provide insights into chromosomal speciation and phenotypic evolution and a foundation of genetic variants for the breeding of sheep and other animals.

5.
NPJ Biofilms Microbiomes ; 8(1): 46, 2022 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-35676509

RESUMO

Rumen microbiota facilitates nutrition through digestion of recalcitrant lignocellulosic substrates into energy-accessible nutrients and essential metabolites. Despite the high similarity in rumen microbiome structure, there might be distinct functional capabilities that enable different ruminant species to thrive on various lignocellulosic substrates as feed. Here, we applied genome-centric metagenomics to explore phylogenetic diversity, lignocellulose-degrading potential and fermentation metabolism of biofilm-forming microbiota colonizing 11 different plant substrates in the camel rumen. Diversity analysis revealed significant variations in the community of rumen microbiota colonizing different substrates in accordance with their varied physicochemical properties. Metagenome reconstruction recovered genome sequences of 590 bacterial isolates and one archaeal lineage belonging to 20 microbial phyla. A comparison to publicly available reference genomes and rumen metagenome-assembled genomes revealed that most isolates belonged to new species with no well-characterized representatives. We found that certain low abundant taxa, including members of Verrucomicrobiota, Planctomycetota and Fibrobacterota, possessed a disproportionately large number of carbohydrate active enzymes per Mb of genome, implying their high metabolic potential to contribute to the rumen function. In conclusion, we provided a detailed picture of the diversity and functional significance of rumen microbiota colonizing feeds of varying lignocellulose composition in the camel rumen. A detailed analysis of 591 metagenome-assembled genomes revealed a network of interconnected microbiota and highlighted the key roles of certain taxonomic clades in rumen function, including those with minimal genomes (e.g., Patescibacteria). The existence of a diverse array of gene clusters encoding for secondary metabolites unveiled the specific functions of these biomolecules in shaping community structure of rumen microbiota.


Assuntos
Microbiota , Rúmen , Animais , Camelus/microbiologia , Lignina , Microbiota/genética , Filogenia , Rúmen/microbiologia
6.
ACS Appl Mater Interfaces ; 14(7): 9480-9491, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35138082

RESUMO

Plasmonic materials have been widely used in chemo/biosensing and biomedicine. However, little attention has been paid to the application of plasmonic materials in terms of the transition from molecular sensing to molecular informatization. Herein, we demonstrated that silver nanoparticles (AgNPs) prepared through facile and rapid microwave heating have multimode colorimetric sensing capabilities to different metal ions (Cr3+, Hg2+, and Ni2+), which can be further transformed into interesting and powerful molecular information technology (massively parallel molecular logic computing and molecular information protection). The prepared AgNPs can quantitatively and sensitively detect Cr3+ and Hg2+ in actual water samples. The AgNPs' multimode-guided multianalyte sensing processing was further investigated to construct a series of basic logic gates and advanced cascaded logic circuits by considering the analytes as the inputs and the colorimetric signals (like color, absorbance, wavelength shift) as the outputs. Moreover, the selective responses and molecular logic computing ability of AgNPs were also utilized to develop molecular cryptosteganography for encrypting and hiding some specific information, which proves that the molecular world and the information world are interconnected and use each other. This research not only opens the door for the transition from molecular sensing to molecular informatization but also provides an excellent opportunity for the construction of the "metaverse" of the molecular world.

7.
PeerJ ; 9: e11520, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34178446

RESUMO

This study aimed to explore the rumen bacterial community of yak in response to dietary supplements during the cold season. In addition, the rumen fermentation products were also analyzed. Twenty-one female domestic yaks were randomly divided into three groups i.e., pure grazing (GG) group, grazing plus oats hay supplement (OG) group, and grazing plus concentrate supplement group (CG). Rumen contents were collected after 90 days to assess rumen fermentation parameters and bacterial community. The GC group presented higher concentrations of ammonia nitrogen (P < 0.001), and total volatile fatty acids (TVFA) (P < 0.001), and lower rumen pH (P < 0.001) compared to other experimental groups. The CG group displayed higher proportions of propionate, butyrate, isobutyrate, and isovalerate while lower A/P ratio compared to other experimental groups. Shannon, Chao1, and ACE values were significantly lower in the OG group compared to GG and CG groups. Anosim test showed significant differences in bacterial community structure between groups but the PCA plot was not very informative to see these differences. Bacteroidetes, Proteobacteria, and Firmicutes were the three dominant phyla in all groups. The genera Oscillospira was more abundant in GG and OG groups. Higher relative abundance of Ruminococcus and Clostridium was observed in the GG group, while Ruminobacter, Corynebacterium, and Selenomonas were more abundant in the CG group. These findings will help in improving our understanding of rumen bacteria in yaks in response to changes in diet.

8.
PeerJ ; 9: e10463, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33510967

RESUMO

BACKGROUND: The rumen microbiota contributes strongly to the degradation of ingested plant materials. There is limited knowledge about the diversity of taxa involved in the breakdown of lignocellulosic biomasses with varying chemical compositions in the rumen. METHOD: We aimed to assess how and to what extent the physicochemical properties of forages influence the colonization and digestion by rumen microbiota. This was achieved by placing nylon bags filled with candidate materials in the rumen of fistulated sheep for a period of up to 96 h, followed by measuring forage's chemical characteristics and community structure of biofilm-embedded microbiota. RESULTS: Rumen degradation for all forages appeared to have occurred mainly during the first 24 h of their incubation, which significantly slowed down after 48 h of rumen incubation, depending on their chemical properties. Random Forest analysis predicted the predominant role of Treponema and Butyrivibrio in shaping microbial diversity attached to the forages during the course of rumen incubation. Exploring community structure and composition of fiber-attached microbiota revealed significant differential colonization rates of forages depending on their contents for NDF and cellulose. The correlation analysis highlighted the significant contribution of Lachnospiraceae and Veillonellaceae to fiber degradation in the sheep rumen. CONCLUSION: Our findings suggested that forage cellulose components are critical in shaping the pattern of microbial colonization and thus their final digestibility in the rumen.

9.
ISME J ; 15(4): 1108-1120, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33262428

RESUMO

Rumen microbiota play a key role in the digestion and utilization of plant materials by the ruminant species, which have important implications for greenhouse gas emission. Yet, little is known about the key taxa and potential gene functions involved in the digestion process. Here, we performed a genome-centric analysis of rumen microbiota attached to six different lignocellulosic biomasses in rumen-fistulated cattle. Our metagenome sequencing provided novel genomic insights into functional potential of 523 uncultured bacteria and 15 mostly uncultured archaea in the rumen. The assembled genomes belonged mainly to Bacteroidota, Firmicutes, Verrucomicrobiota, and Fibrobacterota and were enriched for genes related to the degradation of lignocellulosic polymers and the fermentation of degraded products into short chain volatile fatty acids. We also found a shift from copiotrophic to oligotrophic taxa during the course of rumen fermentation, potentially important for the digestion of recalcitrant lignocellulosic substrates in the physiochemically complex and varying environment of the rumen. Differential colonization of forages (the incubated lignocellulosic materials) by rumen microbiota suggests that taxonomic and metabolic diversification is an evolutionary adaptation to diverse lignocellulosic substrates constituting a major component of the cattle's diet. Our data also provide novel insights into the key role of unique microbial diversity and associated gene functions in the degradation of recalcitrant lignocellulosic materials in the rumen.


Assuntos
Microbiota , Rúmen , Animais , Bovinos , Fermentação , Lignina/metabolismo , Metagenoma , Rúmen/metabolismo
10.
Animals (Basel) ; 10(5)2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32354125

RESUMO

The complex etiology, higher morbidity and mortality, poor prognosis, and expensive cost of calf diarrhea have made it a catastrophic disease in the dairy industry. This study aims to assess the biomarkers in calves with diarrhea and to predict the biomarkers related to the pathway. As subjects, nine calves with diarrhea and nine healthy calves were enrolled, according to strict enrollment criteria. The serum metabolites were detected by a liquid chromatographic tandem mass spectrometry (LC-MS/MS), and then analyzed by online multivariate statistical analysis software to further screen the biomarkers. In addition, the biomarkers involved in the metabolic pathways of calves with diarrhea and healthy calves were analyzed. In the serum of calves with diarrhea, nine biomarkers were found to which several biomarkers exhibited a certain relation. Moreover, these biomarkers were involved in important metabolic pathways, including protein digestion and absorption, ABC transporters, aminoacyl-tRNA biosynthesis, mineral absorption, and fatty acid biosynthesis. All these findings suggested that the imbalance of these markers was closely related to the occurrence and development of calf diarrhea. The targeted regulation of metabolic pathways involved in these biomarkers may facilitate the diagnosis, treatment, and discussion of the mechanism of calf diarrhea.

11.
FEMS Microbiol Ecol ; 96(6)2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32304321

RESUMO

The attachment of rumen microbes to feed particles is critical to feed fermentation, degradation and digestion. However, the extent to which the physicochemical properties of feeds influence the colonization by rumen microbes is still unclear. We hypothesized that rumen microbial communities may have differential preferences for attachments to feeds with varying lignocellulose properties. To this end, the structure and composition of microbial communities attached to six common forages with different lignocellulosic compositions were analyzed following in situ rumen incubation in male Taleshi cattle. The results showed that differences in lignocellulosic compositions significantly affected the inter-sample diversity of forage-attached microbial communities in the first 24 h of rumen incubation, during which the highest dry matter degradation was achieved. However, extension of the incubation to 96 h resulted in the development of more uniform microbial communities across the forages. Fibrobacteres were significantly overrepresented in the bacterial communities attached to the forages with the highest neutral detergent fiber contents. Ruminococcus tended to attach to the forages with low acid detergent lignin contents. The extent of dry matter fermentation was significantly correlated with the populations of Fibrobacteraceae, unclassified Bacteroidales, Ruminococcaceae and Spirochaetacea. Our findings suggested that lignocellulosic compositions, and more specifically the cellulose components, significantly affected the microbial attachment to and thus the final digestion of the forages.


Assuntos
Microbiota , Rúmen , Ração Animal/análise , Animais , Bovinos , Dieta , Fibras na Dieta/metabolismo , Digestão , Fermentação , Lignina/metabolismo , Masculino , Rúmen/metabolismo
12.
Front Vet Sci ; 7: 614054, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33426032

RESUMO

The bovine endometrium is a natural pathogen invasion barrier of the uterine tissues' endometrial epithelial cells that can resist foreign pathogen invasion by controlling the inflammatory immune response. Some pathogens suppress the innate immune system of the endometrium, leading to prolonged systemic inflammatory response through the blood circulation or cellular degradation resulting in bovine endometritis by bacterial endotoxins. The microRNA (miRNA) typically involves gene expression in multicellular organisms in post-transcription regulation by affecting both the stability and the translation of messenger RNA. Accumulated evidence suggests that miRNAs are important regulators of genes in several cellular processes. They are a class of endogenous non-coding RNAs, which play pivotal roles in the inflammatory response of reproductive diseases. Studies confirmed that miRNAs play a key regulatory role in various inflammatory diseases by mediating the molecular mechanism of inflammatory cytokines via signal pathways. It implicates some miRNAs in the occurrence of bovine endometritis, resorting to regulating the activities of some inflammatory cytokines, chemokine, differentially expressed genes, and protein through modulating of specific cellular signal pathways functions. This review dwells on improving the knowledge of the role of miRNAs involvement in inflammatory response as to early diagnosis, control, and prevention of bovine endometritis and consequently enlighten on the molecular improvement of the genes coded by various differentially expressed miRNA through the need to adopt recent genetic technologies and the development of new pharmaceutical preparations.

13.
Analyst ; 144(6): 1881-1891, 2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-30785136

RESUMO

Tumorigenesis, metastasis, and the recurrence of cancer, which may result from the abnormal presence or activation of cancer stem cells (CSCs), are involved in disorders of exchanged matter (biomarkers), energy and information in living organisms. Rapid and sensitive detection and imaging of CSC biomarkers (such as CD133) are helpful for early diagnosis and therapeutic evaluation of tumors. Recently, a preliminary exploration of a few affinity molecules (like peptide-based probes) has just begun for chemical measurements and imaging of CSC biomarker CD133. However, a comprehensive analysis of the matter, energy and information in an artificial molecular system has not been demonstrated and applied to biosensing and disease diagnosis. In this study, a graphene-peptide-based fluorescent sensing system was constructed by utilizing a graphene oxide platform and a CD133-specific recognition peptide and comprehensively analysed with respect to matter (molecular events), energy (fluorescence) and information flow. The molecular event interaction networks in this system were further used to perform molecular logic computing, for the sensitive detection of CSC marker CD133 (with a linear range from 0 to 630 nM and a detection limit of 7.91 nM), and for an application involving targeting the imaging of cells and tumor tissues that highly express CD133 (with a detection limit of 1.1 × 103 cells per mL for CT26 CSCs). The present report will provide more opportunities for the development and design of molecular-level intelligent complex systems and will probably promote the development of artificial intelligent sensing and treatment systems, a molecular-level "Internet of Things", and artificial life.


Assuntos
Antígeno AC133/metabolismo , Técnicas Biossensoriais/métodos , Neoplasias Colorretais/diagnóstico , Corantes Fluorescentes/química , Grafite/química , Imagem Molecular/métodos , Células-Tronco Neoplásicas/patologia , Fragmentos de Peptídeos/química , Animais , Apoptose , Proliferação de Células , Neoplasias Colorretais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Células-Tronco Neoplásicas/metabolismo , Células Tumorais Cultivadas
14.
ACS Appl Mater Interfaces ; 11(9): 8904-8914, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30730133

RESUMO

Inspired by information processing and communication of life based on complex molecular interactions, some artificial (bio)chemical systems have been developed for applications in molecular information processing or chemo/biosensing and imaging. However, little attention has been paid to simultaneously and comprehensively utilize the information computing, encoding, and molecular recognition capabilities of molecular-level systems (such as DNA-based systems) for multifunctional applications. Herein, a graphene-based steganographically aptasensing system was constructed for multifunctional application, which relies on specific molecular recognition and information encoding abilities of DNA aptamers ( Aeromonas hydrophila and Edwardsiella tarda-binding aptamers as models) and the selective adsorption and fluorescence quenching capacities of graphene oxide (GO). Although graphene-DNA systems have been widely used in biosensors and diagnostics, our proposed graphene-based aptasensing system can not only be utilized for fluorescence sensing and in vivo imaging of fish pathogens ( A. hydrophila and E. tarda), but can also function as a molecular-level logic computing system where the combination of matters (specific molecules or materials) as inputs produces the resulting product (matter level) or fluorescence (energy level) changes as two outputs. More importantly and interestingly, our graphene-based steganographically aptasensing system can also serve as a generally doubly cryptographic and steganographic system for sending different secret messages by using pathogen-binding DNA aptamers as information carriers, GO as a cover, and a pair of keys, that is, target pathogen as a public key, the encryption key used to encode or decode a message in DNA as a private key. Our study not only provides a novel nanobiosensing assay for rapid and effective sensing and in vivo imaging of fish pathogens, but also demonstrates a prototype of (bio)molecular steganography as an important and interesting extension direction of molecular information technology, which is helpful in probably promoting the development of multifunctional molecular-level devices or machines.


Assuntos
Aeromonas hydrophila/isolamento & purificação , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Edwardsiella tarda/isolamento & purificação , Peixes/microbiologia , Grafite/química , Aeromonas hydrophila/química , Animais , Aptâmeros de Nucleotídeos/metabolismo , Edwardsiella tarda/química , Microscopia de Força Atômica , Imagem Óptica
15.
Analyst ; 144(1): 274-283, 2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30398257

RESUMO

Sensing of pyrophosphate (PPi) is helpful to better understand many life processes and diagnose various early-stage diseases. However, many traditional reported methods based on artificial receptors for sensing of PPi exhibit some disadvantages including difficulties in designing appropriate binding sites and complicated multi-step assembly/functionalization. Thus, it is significantly important and a big challenge to know how to use a simple molecular self-assembly or an interaction system to solve the above-mentioned limits to achieve the quantitative analysis of specific substances in the system. Based on the natural connection and similarity (such as stimulus responsiveness) between sensing and logic computing, in this study, the Boolean logic tree of molecular self-assembly system based on the cobalt oxyhydroxide (CoOOH) nanoplatform is constructed and applied to organize and connect "plug and play" molecular events (fluorescent dye, acridine orange and anion, PPi). By using molecules as inputs and the corresponding fluorescence signal as the output, the CoOOH-based molecular self-assembly system can be programmed for three-input fluorescent Boolean logic computation, fluorescent three-state logic computation, detection of PPi (linear range from 50 to 6400 nM with a detection limit of 20 nM) and even for imaging in living cancer cells and in vivo (in systems such as Zebrafish and Carassius auratus). Our approach adds a new dimension for expanding molecular logic computing and sensing systems, which will not only provide more opportunities for developing novel logic computing paradigms, but also be helpful in promoting the development and applications of intelligent molecular computing and sensing systems.


Assuntos
Cobalto/química , Difosfatos/sangue , Lógica , Nanoestruturas/química , Óxidos/química , Laranja de Acridina/química , Animais , Corantes Fluorescentes/química , Carpa Dourada , Humanos , Limite de Detecção , Microscopia de Fluorescência/métodos , Peixe-Zebra
16.
Ecotoxicol Environ Saf ; 160: 273-281, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-29852430

RESUMO

Due to rapid change in information technology, many consumer electronics become electronic waste which is the fastest-growing pollution problems worldwide. In fact, many discarded electronics with prefabricated micro/nanostructures may provide a good basis to fulfill special needs of other fields, such as tissue engineering, biosensors, and energy. Herein, to take waste optical discs as an example, we demonstrate that discarded electronics can be directly repurposed as highly anisotropic platforms for in vitro investigation of cell behaviors, such as cell adhesion, cell alignment, and cell-cell interactions. The PC12 cells cultured on biocompatible DVD polycarbonate layers with flat and grooved morphology show a distinct cell morphology, indicating the topographical cue of nanogrooves plays a key role in guidance of neurites growth. By further monitoring cell morphology and alignment of PC12 cells cultured on the DVD nanogrooves at different differentiation times, we find that cell contact interaction with nanotopographies is dynamically adjustable with differentiation time from initial disorder to final order. This study adds a new dimension to not only solving the problems of supply of materials and fabrication of nanopatterns in neural tissue engineering, but may also offering a new promising way of waste minimization or reuse for environmental protection.


Assuntos
Resíduo Eletrônico , Dispositivos Ópticos , Reciclagem , Engenharia Tecidual , Animais , Diferenciação Celular , Nanoestruturas/química , Neurogênese , Células PC12 , Ratos , Propriedades de Superfície
17.
ACS Appl Mater Interfaces ; 10(21): 17704-17713, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29701460

RESUMO

Patterning graphene allows to precisely tune its properties to manufacture flexible functional materials or miniaturized devices for electronic and biomedical applications. However, conventional lithographic techniques are cumbersome for scalable production of time- and cost-effective graphene patterns, thus greatly impeding their practical applications. Here, we present a simple scalable fabrication of wafer-scale three-dimensional (3D) graphene micropatterns by direct laser tuning graphene oxide reduction and expansion using a LightScribe DVD writer. This one-step laser-scribing process can produce custom-made 3D graphene patterns on the surface of a disk with dimensions ranging from microscale up to decimeter scale in about 20 min. Through control over laser-scribing parameters, the resulting various 3D graphene patterns are exploited as scaffolds for controlling cell alignment. The 3D graphene patterns demonstrate their potential to biomedical applications, beyond the fields of electronics and photonics, which will allow to incorporate flexible graphene patterns for 3D cell or tissue culture to promote tissue engineering and drug testing applications.


Assuntos
Grafite/química , Lasers , Óxidos
18.
Anal Chem ; 89(18): 9734-9741, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28809114

RESUMO

The most serious and yet unsolved problems of molecular logic computing consist in how to connect molecular events in complex systems into a usable device with specific functions and how to selectively control branchy logic processes from the cascading logic systems. This report demonstrates that a Boolean logic tree is utilized to organize and connect "plug and play" chemical events DNA, nanomaterials, organic dye, biomolecule, and denaturant for developing the dual-signal electrochemical evolution aptasensor system with good resettability for amplification detection of thrombin, controllable and selectable three-state logic computation, and keypad lock security operation. The aptasensor system combines the merits of DNA-functionalized nanoamplification architecture and simple dual-signal electroactive dye brilliant cresyl blue for sensitive and selective detection of thrombin with a wide linear response range of 0.02-100 nM and a detection limit of 1.92 pM. By using these aforementioned chemical events as inputs and the differential pulse voltammetry current changes at different voltages as dual outputs, a resettable three-input biomolecular keypad lock based on sequential logic is established. Moreover, the first example of controllable and selectable three-state molecular logic computation with active-high and active-low logic functions can be implemented and allows the output ports to assume a high impediment or nothing (Z) state in addition to the 0 and 1 logic levels, effectively controlling subsequent branchy logic computation processes. Our approach is helpful in developing the advanced controllable and selectable logic computing and sensing system in large-scale integration circuits for application in biomedical engineering, intelligent sensing, and control.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Técnicas Eletroquímicas , Lógica , Trombina/análise , Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas/instrumentação , Trombina/química
19.
Int J Clin Exp Med ; 8(10): 17151-66, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26770309

RESUMO

To compare the feasibility, efficiency and safety of coronary angiography (CAG) and interventional procedures between the radial and femoral catheterization approaches in Chinese population using systematic review and meta-analysis, we conducted a search of the studies comparing radial and femoral catheterization approaches in patients underwent either CAG or percutaneous coronary intervention (PCI) in Chinese population. Fixed-effect relative risk (RR) for the primary end points and the second end points were compared between the two approaches. A total of 27 studies (n=8,749 patients) were finally included in the analysis. The success rate of radial approach was slightly lower than that of femoral approach in patients receiving CAG (P=0.004), but similar in patients receiving a further PCI treatment (P=0.11). The risk of major adverse cardiovascular events (MACEs) was similar between two approaches (P=0.27). Radial catheterization had a significantly lower rate of puncture site complications (P<0.00001), but a lower rate of puncture success rate (P=0.02). In patients with acute myocardial infarction (AMI), there was no difference in neither the risk of MACEs nor PCI success rate between two approaches (P=0.23 and 0.45, respectively), but a board line decrease of puncture success rate was observed in radial catheterization group (P=0.04). There were no significant differences in the volumes of contrast media, X-ray exposure time and operation time between the two approaches (all P>0.05). Thus, we concluded that radial approach is a safe method for CAG or PCI compared to traditional femoral approach in Chinese population due to their similar success rate of the procedure and risk of MACEs, and a decreased risk of puncture site complications.

20.
Protein J ; 29(6): 440-4, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20694575

RESUMO

A unique residue W544 in the beta18-beta19 loop of the Bacillus thuringiensis Cry1Ac toxin has been implicated in its toxicity. In this study, the effects of mutations at this residue on protein stability during protease treatment, UV irradiation, and preservation were examined. Residue 544 of Cry1Ac was involved in maintaining structural stability, and substitution of a polar group at this position was unfavorable to protein stability. One mutant, W544F, produced larger crystals and was more stable. This mutant showed greater resistance to UV radiation than the wild type Cry1Ac but retained equal toxicity. This is the first report showing that residue 544 in the Cry1Ac domain III plays a significant role in toxin structural stability. Our W544F mutant is a significant development in terms of field applications of Cry1Ac toxin.


Assuntos
Bacillus thuringiensis/química , Proteínas de Bactérias/química , Endotoxinas/química , Proteínas Hemolisinas/química , Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Eletroforese em Gel de Poliacrilamida , Endotoxinas/genética , Endotoxinas/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Microscopia de Força Atômica , Modelos Moleculares , Mutação , Estabilidade Proteica , Estrutura Terciária de Proteína
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