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1.
Adv Sci (Weinh) ; : e2205087, 2022 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-36529701

RESUMO

Non-noble metal catalysts now play a key role in promoting efficiently and economically catalytic reduction of CO2 into clean energy, which is an important strategy to ameliorate global warming and resource shortage issues. Here, a non-noble bimetallic catalyst of CoFe/Fe3 O4 nanoparticles is successfully designed with a core-shell structure that is well dispersed on the defect-rich carbon substrate for the hydrogenation of CO2 under mild conditions. The catalysts exhibit a high CO2 conversion activity with the rate of 30% and CO selectivity of 99%, and extremely robust stability without performance decay over 90 h in the reverse water gas shift reaction process. Notably, it is found that the reversible exsolution/dissolution of cobalt in the Fe3 O4 shell will lead to a dynamic and reversible deactivation/regeneration of the catalysts, accompanying by shell thickness breathing during the repeated cycles, via atomic structure study of the catalysts at different reaction stages. Combined with density functional theory calculations, the catalytic activity reversible regeneration mechanism is proposed. This work reveals the structure-property relationship for rational structure design of the advanced non-noble metallic catalyst materials with much improved performance.

2.
Inorg Chem ; 61(46): 18504-18509, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36354277

RESUMO

pH detection is related to human beings' life closely. Herein, a porous metal hydrogen-bonded organic framework (MHOF) Co-CDI-CO32- was designed and synthesized, which could be utilized to detect the pH values of strong acids. The sensitivity of pH detection was in the range of pH 2.0-2.4 with an accuracy of 0.1, which mainly depended on the different degree of crystal surface damage. The MHOF Co-CDI-CO32- had potential applications with the advantages of low cost, easy storage, and great sensitivity for pH detection as a pH sensor.


Assuntos
Estruturas Metalorgânicas , Humanos , Ligação de Hidrogênio , Hidrogênio , Porosidade , Concentração de Íons de Hidrogênio
3.
J Mater Chem B ; 10(47): 9931, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36426761

RESUMO

Correction for 'Preparation of nanoscale cationic metal-organic framework Nano Mn(III)-TP for theranostics based on valence changes' by Shijiang Yu et al., J. Mater. Chem. B, 2022, 10, 8988-8995, https://doi.org/10.1039/D2TB01619B.

4.
J Mater Chem B ; 10(43): 8988-8995, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36314257

RESUMO

A single treatment strategy to produce a significant effect on cancer treatment is difficult due to the complex variability of the tumor environment. Herein, considering over-expressed glutathione (GSH) in the tumor environment can reduce Mn3+ to Mn2+, and Mn2+ exhibits an excellent T1-weighted magnetic resonance imaging performance and a good Fenton-like effect. A Mn-based nano-cation metal-organic framework (MOF) with a size of about 200 nm was synthesized and labeled as Nano Mn(III)-TP. It showed an outstanding T1-weighted MRI performance and Fenton-like effect due to valence changes of the Mn ions. Meanwhile, MTXNa@Nano Mn(III)-TP was obtained by loading with the anionic anticancer drug methotrexate disodium (MTXNa), and it could release MTXNa specifically in GSH solution with different pH values and temperatures, resulting in an improvement in the tumor suppressive effect of the Nano Mn(III)-TP. Based on the nanoplatform, the effective combination of magnetic resonance imaging (MRI), CDT and chemotherapy could be used as a potential therapeutic agent for multimodal therapy, which is also expected to be applied to clinical tumor treatment.


Assuntos
Antineoplásicos , Estruturas Metalorgânicas , Nanopartículas , Neoplasias , Humanos , Medicina de Precisão , Nanopartículas/uso terapêutico , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Antineoplásicos/farmacologia
5.
Comput Intell Neurosci ; 2022: 1411670, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36035851

RESUMO

Objective: Based on a retrospective case-control study, logistic multivariate analysis was employed to explore the effects of nursing and psychological factors on the rehabilitation of motor and cognitive function in patients with stroke. Methods: A total of 200 stroke patients treated from February 2019 to April 2020 were enrolled in our hospital. According to the results of exercise and cognitive rehabilitation, the patients with good rehabilitation were divided into the control group (n = 140) and the research group (n = 60). The effects of nursing and psychological factors on the rehabilitation of motor and cognitive function in patients with stroke were analyzed. Results: First of all, we compared the general data. There were significant differences in terms of age, years of education, occupational status, payment methods of medical expenses, family income and the course of the disease, and the difference was statistically significant (P < 0.05). There was no significant difference in general data (P > 0.05). Secondly, we compared the nursing effective rates. The nursing effective rates of the study group were 10 cases, 15 cases, 12 cases, and 23 cases, and the nursing effective rate was 61.67%. In the control group, 78 cases were markedly effective, 33 cases were effective, 25 cases were general and 14 cases were ineffective, and the nursing effective rate was 90.00%. The effective rate of nursing in the study group was higher than that in the control group, and the difference was statistically significant (P < 0.05). There was no significant difference in anxiety and depression scores before nursing (P > 0.05), but they decreased after nursing. In addition, the scores of anxiety and depression in the study group were higher than those in the control group, and the difference was statistically significant (P < 0.05). There was no significant difference in motor function and cognitive function between prenursing and prenursing (P > 0.05); after nursing, the motor function increased and the score of cognitive function decreased. Furthermore, the motor function of the study group was lower compared to the control group, and the score of cognitive function of the study group was higher compared to the control group, and the difference was statistically significant (P < 0.05). The results of the Person correlation analysis showed that there was a significant correlation between nursing anxiety depression and the rehabilitation effect of motor cognitive function in stroke patients. The results of logistic regression analysis showed that age, family income, nursing efficiency, anxiety, and depression were the factors affecting the rehabilitation of motor and cognitive function in stroke patients. Conclusion: Age and family income may be the risk factors affecting the psychological mood of patients. Medical staff should pay attention to the negative emotion of patients and strengthen the nursing intervention of patients.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Estudos de Casos e Controles , Cognição , Humanos , Análise Multivariada , Estudos Retrospectivos
6.
Bioorg Chem ; 127: 105998, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35797861

RESUMO

A series of new 4,7-disubstituted quinoline derivatives was designed, synthesized and evaluated for their antiproliferative activity. The results demonstrated that compounds 10c, 10g, 10i, 10j and 10k displayed potent antiproliferative activity with IC50 value of lower than 5.0 µM against human tumor cell lines, and N-(3-nitrophenyl)-7-((3,4,5-trimethoxybenzyl)oxy)quinoline - 4-amine 10k was found to be the most potent antiproliferative agent against HCT-116, HepG2, BCG-823, A549 and A2780 cell lines with IC50 values of 0.35, 1.98, 0.60, 0.39 and 0.67 µM, respectively. The antitumor efficacy of the representative compound 10k in mice was also evaluated, and the results showed that compound 10k effectively inhibited tumor growth and decreased tumor weight in animal models. Further investigation on mechanism of action indicated that compound 10k could inhibit colorectal cancer growth through inducing autophagy via excessively targeting stabilization of ATG5. Therefore, these quinoline derivatives are a new class of molecules that have the potential to be developed as new antitumor drugs.


Assuntos
Antineoplásicos , Hidroxiquinolinas , Neoplasias Ovarianas , Quinolinas , Animais , Antineoplásicos/farmacologia , Autofagia , Proteína 5 Relacionada à Autofagia/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Camundongos , Estrutura Molecular , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Relação Estrutura-Atividade
8.
World J Clin Cases ; 10(2): 607-617, 2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35097086

RESUMO

BACKGROUND: Lissencephaly (LIS) is a malformation of cortical development with broad gyri, shallow sulci and thickened cortex characterized by developmental delays and seizures. Currently, 20 genes have been implicated in LIS. However, GRP56-related LIS has never been reported. GRP56 is considered one of the causative genes for bilateral frontoparietal polymicrogyria. Here, we report a twin infant with LIS and review the relevant literature. The twins both carried the novel compound heterozygous GPR56 mutations. CASE SUMMARY: A 5-mo-old female infant was hospitalized due to repeated convulsions for 1 d. The patient had a flat head deformity that manifested as developmental delays and a sudden onset of generalized tonic-clonic seizures at 5 mo without any causes. The electroencephalography was normal. Brain magnetic resonance imaging revealed a simple brain structure with widened and thickened gyri and shallow sulci. The white matter of the brain was significantly reduced. Patchy long T1 and T2 signals could be seen around the ventricles, which were expanded, and the extracerebral space was widened. Genetic testing confirmed that the patient carried the GPR56 gene compound heterozygous mutations c.228delC (p.F76fs) and c.1820_1821delAT (p.H607fs). The unaffected father carried a heterozygous c.1820_1821delAT mutation, and the unaffected mother carried a heterozygous c.228delC mutation. The twin sister carried the same mutations as the proband. The patient was diagnosed with LIS. CONCLUSION: This is the first case report of LIS that is likely caused by mutations of the GPR56 gene.

9.
Front Genet ; 12: 648351, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093647

RESUMO

Objective: 1q44 microdeletion syndrome is difficult to diagnose due to the wide phenotypic spectrum and strong genetic heterogeneity. We explore the correlation between the chromosome microdeletions and phenotype in a child with 1q44 microdeletion syndrome, we collected the clinical features of the patient and combined them with adjacent copy number variation (CNV) regions previously reported. Methods: We collected the full medical history of the patient and summarized her clinical symptoms. Whole-exome sequencing (WES) and CapCNV analysis were performed with DNA extracted from both the patient's and her parents' peripheral blood samples. Fluorescent quantitative PCR (q-PCR) was performed for the use of verification to the CNV regions. Results: A 28.7 KB microdeletion was detected in the 1q44 region by whole-exome sequencing and low-depth whole-genome sequencing. The deleted region included the genes COX20 and HNRNPU. As verification, karyotype analysis showed no abnormality, and the results of qPCR were consistent with that of whole-exome sequencing and CapCNV analysis. Conclusion: The patient was diagnosed with 1q44 microdeletion syndrome with clinical and genetic analysis. Analyzing both whole-exome sequencing and CapCNV analysis can not only improve the diagnostic rate of clinically suspected syndromes that present with intellectual disability (ID) and multiple malformations but also support further study of the correlation between CNVs and clinical phenotypes. This study lays the foundation for the further study of the pathogenesis of complex diseases.

10.
BMC Pediatr ; 21(1): 209, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33926407

RESUMO

BACKGROUND: Centronuclear myopathy (CNM), a subtype of congenital myopathy (CM), is a group of clinical and genetically heterogeneous muscle disorders. Since the discovery of the SPEG gene and disease-causing variants, only a few additional patients have been reported. CASE PRESENTATION: The child, a 13-year-old female, had delayed motor development since childhood, weakness of both lower extremities for 10 years, gait swinging, and a positive Gower sign. Her distal muscle strength of both lower extremities was grade IV. The electromyography showed myogenic damage and electromyographic changes. Her 11-year-old sister had a similar muscle weakness phenotype. Gene sequencing revealed that both sisters had SPEG compound heterozygous mutations, and the mutation sites were c.3715 + 4C > T and c.3588delC, which were derived from their parents. These variant sites have not been reported before. The muscle biopsy showed the nucleic (> 20% of fibers) were located in the center of the cell, the average diameter of type I myofibers was slightly smaller than that of type II myofibers, and the pathology of type I myofibers was dominant, which agreed with the pathological changes of centronuclear myopathy. CONCLUSIONS: The clinical phenotypes of CNM patients caused by mutations at different sites of the SPEG gene are also different. In this case, there was no cardiomyopathy. This study expanded the number of CNM cases and the mutation spectrum of the SPEG gene to provide references for prenatal diagnosis and genetic counseling.


Assuntos
Miopatias Congênitas Estruturais , Adolescente , Criança , Feminino , Testes Genéticos , Humanos , Proteínas Musculares/genética , Debilidade Muscular , Músculo Esquelético , Mutação , Miopatias Congênitas Estruturais/diagnóstico , Miopatias Congênitas Estruturais/genética , Fenótipo , Gravidez , Proteínas Serina-Treonina Quinases/genética
11.
Mol Ecol ; 30(2): 592-607, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33226689

RESUMO

Viral lysis and protistan grazing are thought to be the major processes leading to microbial mortality in aquatic environments and thus regulate community diversity and biogeochemical cycling characteristics. Here, we studied nutrient cycling and bacterial responses to cyanophage-mediated photoautotroph lysis and ciliate predation in a model Synechococcus-heterotroph co-culture system. Both viral lysis and Euplotes grazing facilitated the transformation of organic carbon from biomass to dissolved organic matter with convention efficiencies of 20%-26%. The accumulation of ammonium after the addition of phages and ciliates suggested the importance of recycled NH4+ occurred in the interactions between Synechococcus growth and heterotrophic bacterial metabolism of photosynthate. The slower efficiency of P mineralization compared to N (primarily ammonium) indicated that P-containing organic matter was primarily integrated into bacterial biomass rather than being remineralized into inorganic phosphate under C-rich conditions. In the cyanophage addition treatment, both Fluviicola and Alteromonas exhibited rapid positive responses to Synechococcus lysing, while Marivita exhibited an apparent negative response. Further, the addition of Euplotes altered the incubation system from a Synechococcus-driven phycosphere to a ciliate-remodelled zoosphere that primarily constituted grazing-resistant bacteria and Euplotes symbionts. Top-down controls increased co-culture system diversity and resulted in a preference for free-living lifestyles of dominant populations, which was accompanied by the transfer of matter and energy. Our results indicate top-down control was particularly important for organic matter redistribution and inorganic nutrient regeneration between photoautotrophs and heterotrophs, and altered bacterial lifestyles. This study consequently sheds light on marine biogeochemical cycling and the interaction networks within these dynamic ecosystems.


Assuntos
Ecossistema , Nutrientes , Técnicas de Cocultura , Processos Heterotróficos , Dinâmica Populacional
12.
Inorg Chem ; 59(23): 17276-17281, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33231077

RESUMO

A biocompatible Y(III)-based metal-organic framework [Y4(TATB)2]·(DMF)3.5·(H2O) (ZJU-16, H3TATB= 4,4',4''-(1,3,5-triazine-2,4,6-triyl) tribenzoic acid) was synthesized, and it was adopted to load Mn2+ for chemodynamic therapy. Meanwhile, ibuprofen sodium (IBUNa), an anti-inflammatory drug, was introduced to increase the amount of Mn2+ (about 5.66 wt %) due to the low loading capacity of Mn2+. Mn&IBUNa@ZJU-16 which was loaded by Mn2+ and IBUNa exhibited significant effects of chemodynamic therapy and excellent inhibition of the 4T1 tumor cell growth, implying its long-term prospects in chemodynamic therapy and its possibility in bimodal cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Materiais Biocompatíveis/farmacologia , Neoplasias da Mama/tratamento farmacológico , Estruturas Metalorgânicas/farmacologia , Ítrio/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/química , Camundongos , Células Tumorais Cultivadas , Ítrio/química
13.
ACS Omega ; 5(23): 13595-13600, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32566824

RESUMO

A cationic metal-organic framework (MOF) ZJU-48 with one-dimensional pores of about 9.1 × 9.1 Å2 has been prepared from zinc ions, adenine, and carboxyl ligands. ZJU-48 displays excellent water stability for about one week, exhibiting its potential application for adsorption and separation of dyes. Cationic and anionic dyes with similar sizes are adopted to study the adsorbing and separating properties of ZJU-48. Cationic dyes are adsorbed better than anionic dyes because of the negatively charged zeta potential of the material surface, implying its selective adsorption to cationic dyes, and it is charge-based adsorption. Meanwhile, the adsorption ability of the MOF to cationic dyes with different sizes is also investigated. We find that the adsorbed amount decreases with increase in the size of organics ,indicating that it is size-based adsorption. Furthermore, the cationic dye methylene blue (MB) is employed and focused on for its suitable charge and fitting size to evaluate the maximum adsorption capacity and desorption progress of ZJU-48. The results show that the maximum loaded amount of MOF toward MB reaches 582.44 mg/g, and about 90% of loaded dyes can be released from frameworks in N,N-dimethylformamide with NaCl over 6 h, exhibiting satisfactory adsorptive property and possibility as a reusable adsorbent.

14.
mBio ; 11(1)2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32071270

RESUMO

Microbial photoautotroph-heterotroph interactions underlie marine food webs and shape ecosystem diversity and structure in upper ocean environments. Here, bacterial community composition, lifestyle preference, and genomic- and proteomic-level metabolic characteristics were investigated for an open ocean Synechococcus ecotype and its associated heterotrophs over 91 days of cocultivation. The associated heterotrophic bacterial assembly mostly constituted five classes, including Flavobacteria, Bacteroidetes, Phycisphaerae, Gammaproteobacteria, and Alphaproteobacteria The seven most abundant taxa/genera comprised >90% of the total heterotrophic bacterial community, and five of these displayed distinct lifestyle preferences (free-living or attached) and responses to Synechococcus growth phases. Six high-quality genomes, including Synechococcus and the five dominant heterotrophic bacteria, were reconstructed. The only primary producer of the coculture system, Synechococcus, displayed metabolic processes primarily involved in inorganic nutrient uptake, photosynthesis, and organic matter biosynthesis and release. Two of the flavobacterial populations, Muricauda and Winogradskyella, and an SM1A02 population, displayed preferences for initial degradation of complex compounds and biopolymers, as evinced by high abundances of TonB-dependent transporters (TBDTs), glycoside hydrolase, and peptidase proteins. Polysaccharide utilization loci present in the flavobacterial genomes influence their lifestyle preferences and close associations with phytoplankton. In contrast, the alphaproteobacterium Oricola sp. population mainly utilized low-molecular-weight dissolved organic carbon (DOC) through ATP-binding cassette (ABC), tripartite ATP-independent periplasmic (TRAP), and tripartite tricarboxylate transporter (TTT) transport systems. The heterotrophic bacterial populations exhibited complementary mechanisms for degrading Synechococcus-derived organic matter and driving nutrient cycling. In addition to nutrient exchange, removal of reactive oxygen species and vitamin trafficking might also contribute to the maintenance of the Synechococcus-heterotroph coculture system and the interactions shaping the system.IMPORTANCE The high complexity of in situ ecosystems renders it difficult to study marine microbial photoautotroph-heterotroph interactions. Two-member coculture systems of picocyanobacteria and single heterotrophic bacterial strains have been thoroughly investigated. However, in situ interactions comprise far more diverse heterotrophic bacterial associations with single photoautotrophic organisms. In the present study, combined metagenomic and metaproteomic data supplied the metabolic potentials and activities of uncultured dominant bacterial populations in the coculture system. The results of this study shed light on the nature of interactions between photoautotrophs and heterotrophs, improving our understanding of the complexity of in situ environments.


Assuntos
Fenômenos Bioquímicos/fisiologia , Processos Heterotróficos/fisiologia , Metagenoma , Proteômica , Synechococcus/genética , Synechococcus/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Fenômenos Fisiológicos Bacterianos , Sistemas de Secreção Bacterianos , Ecossistema , Glicogênio/metabolismo , Microbiota/genética , Microbiota/fisiologia , Nutrientes , Oceanos e Mares , Estresse Oxidativo , Fotossíntese , RNA Ribossômico 16S/genética , Água do Mar/microbiologia
15.
mSystems ; 4(5)2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31506262

RESUMO

Aerobic anoxygenic photoheterotrophic bacteria (AAPB) represent a bacteriochlorophyll a-containing functional group. Substantial evidence indicates that highly conserved photosynthetic gene clusters (PGCs) of AAPB can be transferred between species, genera, and even phyla. Furthermore, analysis of recently discovered PGCs carried by extrachromosomal replicons (exPGCs) suggests that extrachromosomal replicons (ECRs) play an important role in the transfer of PGCs. In this study, 13 Roseobacter clade genomes from seven genera that harbored exPGCs were used to analyze the characteristics and evolution of PGCs. The identification of plasmid-like and chromid-like ECRs among PGC-containing ECRs revealed two different functions: the spread of PGCs among strains and the maintenance of PGCs within genomes. Phylogenetic analyses indicated two independent origins of exPGCs, corresponding to PufC-containing and PufX-containing puf operons. Furthermore, the two different types of operons were observed within different strains of the same Tateyamaria and Jannaschia genera. The PufC-containing and PufX-containing operons were also differentially carried by chromosomes and ECRs in the strains, respectively, which provided clear evidence for ECR-mediated PGC transfer. Multiple recombination events of exPGCs were also observed, wherein the majority of exPGCs were inserted by replication modules at the same genomic positions. However, the exPGCs of the Jannaschia strains comprised superoperons without evidence of insertion and therefore likely represent an initial evolutionary stage where the PGC was translocated from chromosomes to ECRs without further combinations. Finally, a scenario of PGC gain and loss is proposed that specifically focuses on ECR-mediated exPGC transfer to explain the evolution and patchy distribution of AAPB within the Roseobacter clade.IMPORTANCE The evolution of photosynthesis was a significant event during the diversification of biological life. Aerobic anoxygenic photoheterotrophic bacteria (AAPB) share physiological characteristics with chemoheterotrophs and represent an important group associated with bacteriochlorophyll-dependent phototrophy in the environment. Here, characterization and evolutionary analyses were conducted for 13 bacterial strains that contained photosynthetic gene clusters (PGCs) carried by extrachromosomal replicons (ECRs) to shed light on the evolution of chlorophototrophy in bacteria. This report advances our understanding of the importance of ECRs in the transfer of PGCs within marine photoheterotrophic bacteria.

16.
FEMS Microbiol Lett ; 366(23)2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31977007

RESUMO

In this study, we characterized two induced myoviruses from one marine photoheterotrophic bacterium Porphyrobacter sp. YT40 belonging to the Sphingomonadales family in Alphaproteobacteria. The genome sequence of prophage A is ∼36.9 kb with an average GC content of 67.1%, and its core or functional genes are homologous to Mu or Mu-like phages. Furthermore, induced viral particles from prophage A show a knob-like neck structure, which is only found in bacteriophage Mu. The genome size of prophage B is ∼36.8 kb with an average GC content of 65.3%. Prophage B contains a conserved gene cluster Q-P-O-N-M-L, which is unique in P2 phages. Induced viral particles from prophage B display an icosahedral head with a diameter of ∼55 nm and a 130 ± 5 nm long contractile tail. To our knowledge, this is the first report that characterizes the induced P2-like phage in marine Alphaproteobacteria. Phylogeny analyses suggest that these two types of prophages are commonly found in sequenced bacteria of the Sphingomonadales family. This study sheds light on the ongoing interaction between marine bacteria and phages, and improves our understanding of bacterial genomic plasticity and evolution.


Assuntos
Alphaproteobacteria/virologia , Myoviridae/genética , Microbiologia da Água , Alphaproteobacteria/efeitos dos fármacos , Evolução Molecular , Ordem dos Genes , Genoma Viral , Genômica/métodos , Interações Hospedeiro-Patógeno , Mitomicina/farmacologia , Myoviridae/classificação , Myoviridae/isolamento & purificação , Myoviridae/ultraestrutura , Fases de Leitura Aberta , Filogenia , Prófagos/genética
17.
Dalton Trans ; 47(44): 15882-15887, 2018 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-30362496

RESUMO

A biocompatible metal-organic framework Zn-GA comprising zinc ions and the bio-friendly molecule l-glutamic acid (GA) is synthesized as a drug delivery system, and controlled drug release triggered by pH and thermal stimuli without premature delivery is realized. The anticancer drug methotrexate (MTX) is selected to be encapsulated into the crystal which possesses one-dimensional channels along the a axis. The on-command drug carrier shows superior biocompatibility, extremely low toxicity, satisfactory loading capabilities and excellent dual-responsiveness, indicating its practical application as an efficient drug carrier with controlled release.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Materiais Biocompatíveis/química , Portadores de Fármacos/química , Estruturas Metalorgânicas/química , Metotrexato/administração & dosagem , Temperatura , Animais , Antimetabólitos Antineoplásicos/química , Antimetabólitos Antineoplásicos/farmacologia , Materiais Biocompatíveis/síntese química , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Portadores de Fármacos/síntese química , Ensaios de Seleção de Medicamentos Antitumorais , Ácido Glutâmico/química , Ácido Glutâmico/farmacologia , Concentração de Íons de Hidrogênio , Estruturas Metalorgânicas/síntese química , Metotrexato/química , Metotrexato/farmacologia , Modelos Moleculares , Imagem Óptica , Células PC12 , Ratos , Células Tumorais Cultivadas , Zinco/química , Zinco/farmacologia
18.
Chemistry ; 23(42): 10215-10221, 2017 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-28682004

RESUMO

Drug delivery carriers with a high drug loading capacity and biocompatibility, especially for controlled drug release, are urgently needed due to the side effects and frequently dose in the traditional therapeutic method. In our work, a Zr-based metal-organic framework named ZJU-801, which is isoreticular with NU-801, has been designed and further demonstrated as an excellent drug delivery system (DDS) with a high drug loading of 41.7 %. Such a high drug loading capacity may be ascribed to the appropriate match of the size and the large pore volume of this kind of Zr MOF material. Compared with DS@NU-801, this DDS has successfully achieved on-command heating-activated drug release, which was probably attributed to the bulkier ligand, the better stability, and the intense π-π interaction between ZJU-801 and diclofenac sodium (DS) demonstrated comprehensively by SEM, powder X-ray diffraction (PXRD), FTIR and 13 C solid-state NMR spectroscopy as well as computer simulations. It is worth noting that premature drug release was avoided effectively without any complicated post-modifications. The low cytotoxicity and good biocompatibility of our DDS were certificated by the in vitro favorable results from an MTT assay, a WST-1 assay, and confocal microscopy imaging.


Assuntos
Materiais Biocompatíveis/química , Diclofenaco/química , Portadores de Fármacos/química , Estruturas Metalorgânicas/química , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Diclofenaco/metabolismo , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Espectroscopia de Ressonância Magnética , Estruturas Metalorgânicas/toxicidade , Microscopia Confocal , Microscopia Eletrônica de Varredura , Células PC12 , Porosidade , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo , Difração de Raios X , Zircônio/química
19.
Appl Environ Microbiol ; 82(24): 7205-7216, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27736788

RESUMO

Aerobic anoxygenic phototrophic bacteria (AAPB) are thought to be important players in oceanic carbon and energy cycling in the euphotic zone of the ocean. The genus Citromicrobium, widely found in oligotrophic oceans, is a member of marine alphaproteobacterial AAPB. Nine Citromicrobium strains isolated from the South China Sea, the Mediterranean Sea, or the tropical South Atlantic Ocean were found to harbor identical 16S rRNA sequences. The sequencing of their genomes revealed high synteny in major regions. Nine genetic islands (GIs) involved mainly in type IV secretion systems, flagellar biosynthesis, prophage, and integrative conjugative elements, were identified by a fine-scale comparative genomics analysis. These GIs played significant roles in genomic evolution and divergence. Interestingly, the coexistence of two different photosynthetic gene clusters (PGCs) was not only found in the analyzed genomes but also confirmed, for the first time, to our knowledge, in environmental samples. The prevalence of the coexistence of two different PGCs may suggest an adaptation mechanism for Citromicrobium members to survive in the oceans. Comparison of genomic characteristics (e.g., GIs, average nucleotide identity [ANI], single-nucleotide polymorphisms [SNPs], and phylogeny) revealed that strains within a marine region shared a similar evolutionary history that was distinct from that of strains isolated from other regions (South China Sea versus Mediterranean Sea). Geographic differences are partly responsible for driving the observed genomic divergences and allow microbes to evolve through local adaptation. Three Citromicrobium strains isolated from the Mediterranean Sea diverged millions of years ago from other strains and evolved into a novel group. IMPORTANCE: Aerobic anoxygenic phototrophic bacteria are a widespread functional group in the upper ocean, and their abundance could be up to 15% of the total heterotrophic bacteria. To date, a great number of studies display AAPB biogeographic distribution patterns in the ocean; however, little is understood about the geographic isolation impact on the genome divergence of marine AAPB. In this study, we compare nine Citromicrobium genomes of strains that have identical 16S rRNA sequences but different ocean origins. Our results reveal that strains isolated from the same marine region share a similar evolutionary history that is distinct from that of strains isolated from other regions. These Citromicrobium strains diverged millions of years ago. In addition, the coexistence of two different PGCs is prevalent in the analyzed genomes and in environmental samples.


Assuntos
Genoma Bacteriano , Água do Mar/microbiologia , Sphingomonadaceae/genética , Sphingomonadaceae/isolamento & purificação , Oceano Atlântico , Evolução Molecular , Variação Genética , Genômica , Geografia , Mar Mediterrâneo , Filogenia , Sphingomonadaceae/classificação
20.
Front Microbiol ; 7: 984, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27446024

RESUMO

Aerobic anoxygenic phototrophic bacteria (AAPB) are bacteriochlorophyll a (Bchl a)-containing microbial functional population. Erythrobacter is the first genus that was identified to contain AAPB species. Here, we compared 14 Erythrobacter genomes: seven phototrophic strains and seven non- phototrophic strains. Interestingly, AAPB strains are scattered in this genus based on their phylogenetic relationships. All 14 strains could be clustered into three groups based on phylo-genomic analysis, average genomic nucleotide identity and the phylogeny of signature genes (16S rRNA and virB4 genes). The AAPB strains were distributed in three groups, and gain and loss of phototrophic genes co-occurred in the evolutionary history of the genus Erythrobacter. The organization and structure of photosynthesis gene clusters (PGCs) in seven AAPB genomes displayed high synteny of major regions except for few insertions. The 14 Erythrobacter genomes had a large range of genome sizes, from 2.72 to 3.60 M, and the sizes of the core and pan- genomes were 1231 and 8170 orthologous clusters, respectively. Integrative and conjugative elements (ICEs) were frequently identified in genomes we studied, which might play significant roles in shaping or contributing to the pan-genome of Erythrobacter. Our findings suggest the ongoing evolutionary divergence of Erythrobacter genomes and the scattered distribution characteristic of PGC.

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