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1.
Sci Total Environ ; 618: 1254-1267, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29089134

RESUMO

Massive partial sequencing of 16S rRNA genes has become the predominant tool used for studying microbial ecology. However, determining which hypervariable regions and primer sets should be used for screening microbial communities requires extensive investigation if controversial results are to be avoided. Here, the performances of different variable regions of the 16S rRNA gene on bacterial diversity studies were evaluated in silico with respect to the SILVA non-redundant reference database (SILVA SSU Ref 123NR), and subsequently verified using samples from Lake Taihu in China, a eutrophic lake. We found that the bacterial community composition results were strongly impacted by the different V regions. The results show that V1-V2 and V1-V3 regions were the most reliable regions in the full-length 16S rRNA sequences, while most V3 to V6 regions (including V3, V4, V3-V4, V5, V4-V5, V6, V3-V6, V4-V6, and V5-V6) were more closely aligned with the SILVA SSU Ref 123NR database. Overall, V4 was the most prominent V region for achieving good domain specificity, higher coverage and a broader spectrum in the Bacteria domain, as confirmed by the validation experiments. S-D-Bact-0564-a-S-15/S-D-Bact-0785-b-A-18 is, therefore, a promising primer set for surveying bacterial diversity in eutrophic lakes.


Assuntos
Bactérias/genética , Monitoramento Ambiental , Eutrofização , Lagos/microbiologia , Bactérias/classificação , China , Genes Bacterianos , Variação Genética , RNA Ribossômico 16S , Análise de Sequência de DNA
2.
Semin Cell Dev Biol ; 69: 3-8, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28577926

RESUMO

Spectraplakins are a family of evolutionarily conserved gigantic proteins and play critical roles in many cytoskeleton-related processes. Microtubule actin crosslinking factor 1 (MACF1) is one of the most versatile spectraplakin with multiple isoforms. As a broadly expressed mammalian spectraplakin, MACF1 is important in maintaining normal functions of many tissues. The loss-of-function studies using knockout mouse models reveal the pivotal roles of MACF1 in embryo development, skin integrity maintenance, neural development, bone formation, and colonic paracellular permeability. Mutation in the human MACF1 gene causes a novel myopathy genetic disease. In addition, abnormal expression of MACF1 is associated with schizophrenia, Parkinson's disease, cancer and osteoporosis. This demonstrates the crucial roles of MACF1 in physiology and pathology. Here, we review the research advances of MACF1's roles in specific tissue and in human diseases, providing the perspectives of MACF1 for future studies.


Assuntos
Doença , Proteínas dos Microfilamentos/metabolismo , Especificidade de Órgãos , Humanos , Proteínas dos Microfilamentos/química , Cicatrização
3.
Environ Sci Pollut Res Int ; 24(14): 12796-12808, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28364202

RESUMO

Understanding of the bacterial community structure in drinking water resources helps to enhance the security of municipal water supplies. In this study, bacterial communities were surveyed in water and sediment during a heavy cyanobacterial bloom in a drinking water resource of Lake Taihu, China. A total of 325,317 high-quality sequences were obtained from different 16S ribosomal RNA (rRNA) regions (V3, V4, and V6) using the Miseq sequencing platform. A notable difference was shown between the water and sediment samples, as predominated by Cyanobacteria, Proteobacteria, and Actinobacteria in the water and Proteobacteria, Chloroflexi, and Verrucomicrobia in the sediment, respectively. The LD12 family dominated the water surface and was tightly associated with related indicators of cyanobacterial propagation, indicating involvement in the massive proliferation of cyanobacterial blooms. Alternatively, the genus Nitrospira dominated the sediment samples, which indicates that nitrite oxidation was very active in the sediment. Although pathogenic bacteria were not detected in a large amount, some genera such as Mycobacterium, Acinetobacter, and Legionella were still identified but in very low abundance. In addition, the effects of different V regions on bacterial diversity survey were evaluated. Overall, V4 and V3 were proven to be more promising V regions for bacterial diversity survey in water and sediment samples during heavy water blooms in Lake Taihu, respectively. As longer, cheaper, and faster DNA sequencing technologies become more accessible, we expect that bacterial community structures based on 16S rRNA amplicons as an indicator could be used alongside with physical and chemical indicators, to conduct comprehensive assessments for drinking water resource management.


Assuntos
Lagos/microbiologia , RNA Ribossômico 16S/genética , China , Cianobactérias/classificação , Água Potável
4.
Bioorg Med Chem Lett ; 27(9): 2010-2013, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28320617

RESUMO

Phenazine-1-carboxylic acid (PCA) as a natural product widely exists in microbial metabolites of Pseudomonads and Streptomycetes and has been registered for the fungicide against rice sheath blight in China. To find higher fungicidal activities compounds and study the effects on fungicidal activities after changing the carboxyl group of PCA, we synthesized a series of PCA derivatives by modifying the carboxyl group of PCA and their structures were confirmed by 1H NMR and HRMS. Most compounds exhibited significant fungicidal activities in vitro. In particular, compound 6 exhibited inhibition effect against Rhizoctonia solani with EC50 values of 4.35mg/L and compound 3b exhibited effect against Fusarium graminearum with EC50 values of 8.30mg/L, compared to the positive control PCA with its EC50 values of 7.88mg/L (Rhizoctonia solani) and 127.28mg/L (Fusarium graminearum), respectively. The results indicated that the carboxyl group of PCA could be modified to be amide group, acylhydrazine group, ester group, methyl, hydroxymethyl, chloromethyl and ether group etc. And appropriate modifications on carboxyl group of PCA were useful to extend the fungicidal scope.


Assuntos
Fungicidas Industriais/química , Fungicidas Industriais/toxicidade , Fusarium/efeitos dos fármacos , Doenças das Plantas/prevenção & controle , Rhizoctonia/efeitos dos fármacos , Fungicidas Industriais/síntese química , Oryza/microbiologia , Fenazinas/síntese química , Fenazinas/química , Fenazinas/toxicidade , Doenças das Plantas/microbiologia , Relação Estrutura-Atividade , Triticum/microbiologia
5.
J Mater Sci Mater Med ; 27(11): 169, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27709459

RESUMO

We describe an electrostatic droplet generation method to prepare a novel carboxymethyl chitosan-graphene oxide hybrid particles for delivery purpose. Under an adjustable electrostatic field, graphene oxide and carboxymethyl chitosan mixed solution was sprayed as uniform micro-droplets, which were solidified as particles in CaCl2 solution. Such hybrid particles are wished to have excellent stability in saline solution, and better delivery properties than pristine carboxymethyl chitosan particles. The effects of micro-droplets generation conditions on particles formation were systematically investigated. At conditions of 40 mg/ml of carboxymethyl chitosan, 2 mg/ml of graphene oxide, 3 ml/h of feed speed, electrostatic field parameters was 9 kV and 20 cm, uniformly sized carboxymethyl chitosan-graphene oxide particles in the diameter range of 250-300 µm was successfully prepared. In NaCl saline, these particles could maintain stable for at least a week, while pristine carboxymethyl chitosan particles quickly collapsed within an hour. The results of loading experiments showed that carboxymethyl chitosan-graphene oxide particles could effectively adsorb gatifloxacin, ofloxacin, bovine serum albumin, lysozyme, doxorubicin hydrochloride. And gatifloxacin was chosen as a model drug to study the exact effect of graphene oxide content on the loading and release properties. In 40:2 group, the highest loading capacity of 0.45 ± 0.19 mg/mg was achieved, and also a good sustained release was available. Above all, we believed that carboxymethyl chitosan-graphene oxide particles as a versatile carrier, has great potential in Medicine and Pharmacy.


Assuntos
Quitosana/análogos & derivados , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Grafite/química , Óxidos/farmacologia , Adsorção , Animais , Quitosana/química , Doxorrubicina , Fluoroquinolonas/química , Gatifloxacina , Humanos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanopartículas , Óxidos/química , Tamanho da Partícula , Solubilidade , Eletricidade Estática
6.
Appl Opt ; 52(13): 3039-47, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23669772

RESUMO

The method of superimposing multiple phase patterns to generate and deflect multi Airy beams is proposed in this paper. A Dammann grating and an optimized splitting grating are superimposed, respectively, with an Airy cubic phase pattern to generate an array of 4×4 equal-space Airy beams. By adding a deflection grating to the superimposed phase patterns, the transverse self-accelerated Airy beams array can be deflected arbitrarily in two-dimensional plane. The impacts of superimposed phase patterns on the transverse acceleration and size of main lobe of Airy beams in array are discussed in this paper. Meanwhile, the accuracy of the steering method and the impact of the phase modulation depth on the size of the Airy beams are introduced.

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