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1.
Nanoscale ; 13(38): 16189-16196, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34545905

RESUMO

Colloidal photonic crystals (CPCs) with a highly ordered crystal structure have attracted great attention in displays, colorimetric sensors and solar energy utilization fields. However, the easily cracking microstructure, inferior assembly efficiency and low refractive index contrast result in poor structural colors. Herein, we develop core-shell poly(styrene-acrylic)@polypyrrole (P(St-AA)@PPy) colloidal nanoparticles by the in situ chemical coupling reaction via droplet microfluidic technology. By membrane separation-assisted assembly (MSAA) and electrostatic spraying strategies, the P(St-AA)@PPy colloidal nanoparticles are assembled into the CPC film, which presents high assembly efficiency and saturated angle-independent structural colors, due to the light-absorbing PPy shell and hydrogen-bond interaction between nanoparticles. Benefitting from these outstanding performances, the P(St-AA)@PPy film shows excellent photothermal properties, which can realize a solar vaporization rate of 1.5825 kg m-2 h-1, corresponding to a light-to-vapor efficiency of 94.20%, under 1.0 sun solar irradiance conditions. Our findings open a path for the design of functional CPCs and new-generation photothermal applications.

2.
Chem Commun (Camb) ; 57(45): 5550-5553, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-33969841

RESUMO

A new design strategy through the synergy of Mo(vi)-Mo(v) intervalence charge transfer and π(radical)-π(radical/cation) interactions is proposed to obtain semiconductors with photoresponsive ranges covering the whole UV-SWIR (ultraviolet-shortwave near-infrared; ca. 250-3000 nm) region. With this strategy, a viologen-based molybdate semiconductor with a UV-SWIR photoresponsive range was obtained through UV/X-ray irradiation or thermal annealing. The thermally annealed semiconductor has the highest conversion and the best photocurrent response in the range of 355-2400 nm.

3.
Nanoscale ; 12(38): 19953-19962, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32996527

RESUMO

Hydrophobic photonic crystals (PCs) has been increasingly appreciated as a promising functional material due to their distinct surface characteristic of structural color and hydrophobicity. However, it remains a challenge to fabricate hydrophobic PCs via a one-step process. Inspired by the development of high-performance waterborne coatings, we propose an easy-to-perform and high-efficiency strategy to construct hydrophobic building blocks (diameter of 221, 247, 276 and 305 nm), where the umbelli-form hydrophobic long chain (veova10 Cn > 9) was loaded onto polystyrene (PS) colloidal particles in situ. Taking advantage of the hydrophobic driving force between the colloidal particles, large-scale colloidal photonic crystals (CPCs) film with crack-free morphology was obtained efficiently. The derived CPCs exhibit robust mechanical stability, prominent hydrophobicity and excellent optical properties. In addition, the colloidal latex holds great potential toward PCs coatings on a variety of substrates (glass, plastic and steel) with excellent adhesiveness. Furthermore, we contrive to construct angle-independent structural color films and supraballs, and explore their application in quantum dots (QDs) fluorescence enhancement, which achieved an enhancement effect by more than eight times. From the standpoint of practical applications, we achieved the flexible high-brightness wearable light-emitting diode (LED) displays. This work will lay a foundation for the development of high-efficiency PCs building blocks, and indicate the direction for the meaningful application of CPCs.

4.
Fitoterapia ; 146: 104716, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32866541

RESUMO

A phytochemical investigation on the MeOH extract of the red alga Laurencia composita Yamada led to the discovery of six new highly halogenated sesquiterpenoids, including two bisabolane-type sesquiterpenoids (1 and 2), one nerolidol derivative (7), and three chamigrane-type sesquiterpenoids (9, 10, and 18), together with 13 known sesquiterpenoids. Their structures, including relative configuration, were elucidated by extensive spectroscopic analysis, and by comparison with data for related known compounds. The absolute configuration at C-10 of laurecomposin A (1) was determined by the modified Mosher's method. Halonerolidol (7) is the first naturally occurring halogenated nerolidol derivative, while compositacin L (9) represents the third example of chamigranes having a C-10 carbonyl group. Antifungal, antibacterial, and receptor tyrosine kinase inhibitory activities of these isolates were evaluated. The results showed that compounds 1-3 and 5 exhibited significant antifungal activity against Microsporum gypseum (Cmccfmza) with MIC values of 4, 8, 8, and 4 µg/mL, respectively. Additionally, compounds 1-3 and 5 also displayed promising antibacterial activity against Gram-positive bacteria Staphylococcus aureus Newman strain with MIC values ranging from 10.9 to 26.8 µg/mL.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Laurencia/química , Sesquiterpenos/farmacologia , Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Arthrodermataceae/efeitos dos fármacos , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , China , Estrutura Molecular , Proteínas Tirosina Quinases/metabolismo , Sesquiterpenos/isolamento & purificação , Staphylococcus aureus/efeitos dos fármacos
5.
Nat Commun ; 11(1): 1179, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32132532

RESUMO

Extending photoresponse ranges of semiconductors to the entire ultraviolet-visible (UV)-shortwave near-infrared (SWIR) region (ca. 200-3000 nm) is highly desirable to reduce complexity and cost of photodetectors or to promote power conversion efficiency of solar cells. The observed up limit of photoresponse for organic-based semiconductors is about 1800 nm, far from covering the UV-SWIR region. Here we develop a cyanide-bridged layer-directed intercalation approach and obtain a series of two viologen-based 2D semiconductors with multispectral photoresponse. In these compounds, infinitely π-stacked redox-active N-methyl bipyridinium cations with near-planar structures are sandwiched by cyanide-bridged MnII-FeIII or ZnII-FeIII layers. Radical-π interactions among the infinitely π-stacked N-methyl bipyridinium components favor the extension of absorption range. Both semiconductors show light/thermo-induced color change with the formation of stable radicals. They have intrinsic photocurrent response in the range of at least 355-2400 nm, which exceeds all reported values for known single-component organic-based semiconductors.

6.
J Dairy Sci ; 103(4): 3066-3075, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32037182

RESUMO

Although freeze-drying is an excellent method for preserving microorganisms, it inevitably reduces cell activity and function. Moreover, probiotic strains differ in terms of their sensitivity to the freeze-drying process. Therefore, it is necessary to optimize the variables relevant to this process. The pre-freezing temperature is a critical parameter of the freeze-drying process, but it remains unclear whether the optimal pre-freezing temperature differs among strains and protectants. This study explored the effects of 4 different pre-freezing temperatures on the survival rates of different Lactobacillus plantarum strains after freeze-drying in the presence of different protectants. Using phosphate-buffered saline solution and sorbitol as protectants, pre-freezing at -196°C, -40°C, and -20°C ensured the highest survival rates after freeze-drying for AR113, AR307, and WCFS1, respectively. Using trehalose, pre-freezing at -20°C ensured the best survival rate for AR113, and -60°C was the best pre-freezing temperature for AR307 and WCFS1. These results indicate that the pre-freezing temperature can be changed to improve the survival rate of L. plantarum, and that this effect is strain-specific. Further studies have demonstrated that pre-freezing temperature affected viability via changes in cell membrane integrity, membrane permeability, and lactate dehydrogenase activity. In summary, pre-freezing temperature is a crucial factor in L. plantarum survival after freeze-drying, and the choice of pre-freezing temperature depends on the strain and the protectant.


Assuntos
Crioprotetores/farmacologia , Lactobacillus plantarum/fisiologia , Probióticos , Trealose/farmacologia , Animais , Temperatura Baixa , Liofilização/veterinária , Congelamento
7.
Biomed Chromatogr ; 34(4): e4795, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31967660

RESUMO

In this study, we focused on studying the changes in urine metabolites in hyperlipidemic rats using ultra-performance liquid chromatography coupled with quadrupole time-of-fight mass spectrometry (UPLC-Q-TOF/MS) and metabolomics, as well as the effect of Citri Reticulatae Chachiensis Pericarpium (CRCP) on hyperlipidemia. These urine samples were examined by UPLC-Q-TOF/MS to obtain MS data. The MS data were analyzed by principal component analysis and partial least squares-discriminant analysis to identify the differential metabolites. CRCP reduced the body weight and levels of triglycerides, total cholesterol and low-density lipoprotein cholesterol and abnormally decreased high-density lipoprotein cholesterol in hyperlipidemic rats, which were significantly raised by a high-fat diet. Twenty-seven potential biomarkers were identified within the complex sample matrix of urine. Fourteen biomarkers increased in the hyperlipidemia rats compared with normal rats. Meanwhile, 13 biomarkers decreased. CRCP reversed abnormal changes in biomarkers, including 5-l-glutamyl-taurine, 5-aminopentanoic acid, cis-4-octenedioic acid and 2-octenedioic acid. These biomarkers show that hyperlipidemia is related to the metabolic pathways of taurine and hypotaurine metabolism, fatty acid biosynthesis, and arginine and proline metabolism. CRCP mainly prevents hyperlipidemia by intervening in these metabolic pathways.


Assuntos
Citrus/química , Dieta Hiperlipídica , Metaboloma/efeitos dos fármacos , Preparações de Plantas , Substâncias Protetoras , Animais , Biomarcadores/urina , Frutas/química , Masculino , Metabolômica , Preparações de Plantas/química , Preparações de Plantas/farmacologia , Substâncias Protetoras/química , Substâncias Protetoras/farmacologia , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
8.
ACS Appl Mater Interfaces ; 12(2): 2816-2825, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31840979

RESUMO

Metal-organic framework (MOF)-directed photonic structure materials have inspired great attention for extended and enhanced functions. However, the direct construction of photonic crystals (PCs) with MOF particles as building blocks still remains a challenge. Herein, we designed and synthesized monodisperse polyamidoamine (PAMAM) dendrimer-modified zeolitic imidazolate framework (ZIF-8) particles (PAMAM@ZIF-8) via a postsynthetic method, rendering ZIF-8 with hydrophilicity. It was found that the PAMAM@ZIF-8 particles could directly assemble into a uniform photonic structure and effectively suppressed the coffee-ring effect, forming homogeneous PC films with different structural colors. A PC pattern with angle-dependent colors was also achieved, which might have potential applications in the field of anticounterfeiting printing. More importantly, by taking advantages of a membrane separation-assisted assembly process, a colorful and robust PC film was accomplished on the surface of reduced graphene oxide (rGO). The hierarchal PAMAM@ZIF-8/rGO film demonstrates a superior separation ability toward organic dye solutions, which enriches the function of PC materials. This work gives a new insight into the fabrication of MOF-based functional PC materials, which will extend the application of PCs in the high selective and effective separation field.

9.
J Pharm Biomed Anal ; 171: 218-231, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31072532

RESUMO

Using ultra high performance liquid chromatography quadrupole/time-of-flight mass spectrometry (UPLC-QTOFMS) based metabolomics, we focused on developing a method for the comprehensive distinction between Citri Reticulatae Blanco Pericarpium(CRBP) and Citri Reticulatae Chachi Pericarpium (CRCP), as well as the CRCP within different storage years in this study. Through this, we hope to enhance Citri Reticulatae Pericarpium (CRP) Quality Control system. Using UNIFI software and an online database identified chemical components in the 3-30 years CRCP(40 batches) and CRBP (10 batches)samples, and multivariate statistical analysis methods and heat-map were applied to distinguish between CRCP and CRBP and CRCP in different storage years. The results showed that a total of 92 compounds were identified from CRCP and CRBP samples, most of which were flavonoids. Principal component analysis (PCA) and orthogonal partial least squares discrimination analysis (OPLS-DA) indicated that it can effectively distinguish between CRBP and CRCP and various storage years CRCP, and 19 metabolites were identified as potential markers for distinguishing between CRBP and CRCP, and 15 potential markers showed a higher level of CRCP than CRBP. At the same time, 31 metabolites were identified to distinguish CRCP in different storage years, metabolite levels increased in 3-10 years and decreased after 15-30 years. Therefore, this approach can effectively distinguish between CRCP and CRBP and CRCP with different storage years, and may also provide a feasible strategy for the certification of Chinese herbal medicines from different species and storage years.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Citrus/química , Medicamentos de Ervas Chinesas/química , Frutas/química , Metabolômica/métodos , Espectrometria de Massas em Tandem/métodos , Citrus/normas , Armazenamento de Medicamentos , Medicamentos de Ervas Chinesas/normas , Frutas/normas , Controle de Qualidade
10.
Angew Chem Int Ed Engl ; 58(28): 9475-9478, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31070835

RESUMO

Breaking the intrinsic rule of semiconductors that conductivity increases with increase of temperature and realizing a dramatic dropping of conductivity at high temperature may arouse new intriguing applications, such as circuit overload or over-temperature protecting. This goal has now been achieved through T-type electron-transfer photochromism of one organic semiconductor assembled by intermolecular cation⋅⋅⋅π interactions. Conductivity of the viologen-based model semiconductor (H2 bipy)(Hox)2 (H2 bipy=4,4'-bipyridin-1,1'-dium; ox=oxalate) increased by 2 orders of magnitude after photoinduced electron transfer (a record for photoswitchable organic semiconductors) and generation of radical cation⋅⋅⋅π interactions, and fell by approximately 81 % at 100 °C through reverse electron transfer and degeneration of the radical cation⋅⋅⋅π interactions. The model semiconductor has at least two different electron transfer pathways in the decoloration process.

11.
Chem Commun (Camb) ; 55(9): 1241-1244, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30632553

RESUMO

A new metal-organic framework with excellent water stability, {H[(N(CH3)4)2][Gd3(NIPA)6]}·3H2O (1, H2NIPA = 5-nitroisophthalic acid), displays a proton conductivity of 7.17 × 10-2 S cm-1 (at 75 °C and 98% relative humidity), which is among the highest values for proton-conducting MOFs.

12.
Shanghai Kou Qiang Yi Xue ; 27(1): 28-33, 2018 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-29946637

RESUMO

PURPOSE: To investigate the expression of Kruppel-like factor 5 (KLF5) in human periodontal ligament cells (hPDLCs) under cyclic tensile stress (CTS) and its effect on proliferation and osteogenic differentiation of hPDLCs. METHODS: hPDLCs were primarily cultured in vitro by tissue explant and enzyme digestion method. RT-PCR and Western blot were used to detect mRNA and protein expression of KLF5 in hPDLCs stimulated by 10% CTS at a frequency of 0.5 Hz for 1, 4, 8, 12 and 24 h, respectively.KLF5 was then knocked-down in hPDLCs using siRNA (si-KLF5) and its mRNA expression was determined by RT-PCR. Meanwhile, basic fibroblast growth factor (FGF2) was overexpressed in KLF-5 silenced hPDLCs by using pcDNA3.1-FGF2. After stimulation with CTS for 8 h, the proliferation of hPDLCs was assayed by CCK-8 kit, alkaline phosphatase (ALP) activity was assayed by ALP kit, the mRNA expression of Runx2 and Osterix was examined by RT-PCR, and the protein expression of Runx2, Osterix, FGF2, GSK-3ß, P-GSK-3ß (ser 9), ß-catenin was determined by Western blot. The data were analyzed using SPSS 22.0 software package. RESULTS: Stimulation with 10% CTS time-dependently induced mRNA and protein expression of KLF5 in hPDLCs. Transfection of si-KLF5 significantly reduced the proliferation of hPDLCs, decreased ALP activity and expression of Runx2 and Osterix in hPDLCs stimulated by 10% CTS. Simultaneously, CTS-induced activation of FGF2-GSK-3ß/ß-catenin signaling pathway was also inhibited by si-KLF5 transfection. However, overexpression of FGF2 can partly neutralized the inhibitiory effect of si-KLF5 on proliferation and osteogenic differentiation of hPDLCs subjected to 10% CTS. CONCLUSIONS: KLF5 promotes proliferation and osteogenesis differentiation of hPDLCs subjected to cyclic tensile stress through FGF2-GSK-3ß/ß-catenin signaling pathway.


Assuntos
Diferenciação Celular , Osteogênese , Ligamento Periodontal , Proliferação de Células , Células Cultivadas , Expressão Gênica , Glicogênio Sintase Quinase 3 beta , Humanos , Fatores de Transcrição Kruppel-Like , Ligamento Periodontal/metabolismo , Proteínas/metabolismo , Resistência à Tração
13.
Medicine (Baltimore) ; 97(24): e10717, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29901574

RESUMO

RATIONALE: Paraneoplastic cerebellar degeneration (PCD) is an immune-mediated neurological deficit affecting the cerebellum. Anti-Yo antibody positive PCD is a rare occurrence most likely associated with gynecologic or breast malignancies. The identification of the underlying tumor is a diagnostic challenge in many of these patients. PATIENT CONCERNS: We present a 68-year-old woman with acute symptoms of PCD as a first sign of underlying occult malignancy. Further investigation revealed a positive anti-Yo antibody. Although brain magnetic resonance imaging (MRI) was unremarkable, positron emission tomography (PET)/computed tomography (CT) revealed intense hypermetabolism of cerebellum and diffused hypometabolism in the rest of brain. On 1-year follow-up, despite the primary malignancy is still unknown, her symptoms improved significantly after immunotherapy. DIAGNOSES: Paraneoplastic cerebellar degeneration. INTERVENTIONS: The patient was given IV methylprednisolone 500 mg once a day for 5 consecutive days, followed by oral prednisone 60 mg once a day for 3 months. OUTCOMES: The patient's symptoms were gradually improved during the hospitalization period. On one year follow up, she was able to walk independently and perform some simple tasks. LESSONS: Cerebellar hypermetabolism in PCD suspected patients may help confirming the diagnosis in an earlier stage and may predict a better outcome after immunotherapy.


Assuntos
Neoplasias Primárias Desconhecidas/complicações , Degeneração Paraneoplásica Cerebelar/diagnóstico , Idoso , Cerebelo/diagnóstico por imagem , Cerebelo/patologia , Feminino , Glucocorticoides/uso terapêutico , Humanos , Imunoterapia/métodos , Neoplasias Primárias Desconhecidas/diagnóstico por imagem , Proteínas do Tecido Nervoso/imunologia , Degeneração Paraneoplásica Cerebelar/patologia , Degeneração Paraneoplásica Cerebelar/terapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos
14.
Eur J Obstet Gynecol Reprod Biol ; 218: 12-20, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28926725

RESUMO

OBJECTIVE(S): X-ray repair cross-complementing group 1(XRCC1) gene is one of the DNA repair pathway genes playing a vital role in endometriosis risk. Various studies have explored the association between them, however, the results remained inconsistent. So to confirm the association between XRCC1 Arg399Gln polymorphism and the risk of endometriosis, a meta-analysis was conducted. STUDY DESIGN: PubMed, Web of Science, Science Director, Cochrane Library, Google Scholar, China National Knowledge Infrastructure (CNKI) and Wanfang Data databases were searched to identify the all relevant studies before Sep. 30, 2016 focusing on the association between XRCC1 Arg399Gln polymorphism and the risk of endometriosis. Summary odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated and analyzed by Review Manager 5.2 and Stata 12 to assess the strength of the association. Meanwhile, Begg's test was used to check the publication bias. RESULTS: The present meta-analysis identified 6 studies with 646 cases and 616 controls. The overall analysis revealed that the AA genotype exhibited a significant association with a decreased risk for endometriosis compared with GG (OR=0.43, 95%CI=0.20-0.94, P=0.03), GA (OR=0.57, 95%CI=0.35-0.95, P=0.03) and GG+GA (OR=0.54, 95%CI=0.31-0.96, P=0.04) respectively. In addition, subgroup analyses based on varied regions indicated that a total comparisons of allelic and various genetic models had statistical significances among Asians (A allele vs. G allele: OR=0.62, 95%CI=0.48-0.81, P=0.0004; AA vs. GG: OR=0.22, 95%CI=0.11-0.46, P<0.0001; AA vs. GA: OR=0.32, 95%CI=0.16-0.63, P=0.001; AA vs. GG+GA: OR=0.28, 95%CI=0.14-0.54, P=0.0002; AA+GA vs. GG: OR=0.28, 95%CI=0.14-0.54, P=0.008) but not among Middle Eastern. The Begg's test did not reveal any obvious publication bias in the present study. CONCLUSION(S): Our meta-analysis suggested that Arg399Gln in XRCC1 was associated with endometriosis risk. And especially in Asians, the A allele might be a preventive factor for this disease. Further well-designed researches with larger sample size and various regions are required to validate our conclusion.


Assuntos
Endometriose/genética , Polimorfismo de Nucleotídeo Único , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/genética , Alelos , Estudos de Casos e Controles , Feminino , Heterogeneidade Genética , Humanos , Reação em Cadeia da Polimerase , Fatores de Risco
15.
Eur J Obstet Gynecol Reprod Biol ; 212: 101-109, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28363185

RESUMO

PURPOSE: Methylenetetrahydrofolate reductase is one of the key enzymes in folate metabolism. But the association between polymorphism and the risk of male infertility is still controversial. Therefore, this study used a meta-analysis on the collection of data to analyze MTHFR gene C677T polymorphism (known as c.665 C>T, rs1801133, p.Ala222Val). METHODS: PubMed, EMBASE, China National Knowledge Infrastructure (CNKI), and Wan fang. Data were searched to identify eligible studies. We sifted the data collection by Hardy-Weinberg equilibrium calculator and used odds ratios (ORs) and 95% confidence intervals (95% CIs) to conduct data through RevMan5.0 and StataSE12.0 software. RESULTS: A total of 15 studies have 3853 patients with infertility and 3613 healthy controls in this meta-analysis. Our results showed that T variant of MTHFR C677T gene polymorphism was significantly associated with an increased risk of male infertility (forT vs. C: OR=1.38, 95% CI=1.18-1.63; for TT vs. CC: OR=1.86, 95% CI=1.36-2.54; for CT vs. CC: OR=1.34, 95% CI=1.03-1.74; for TT vs. CT: OR=1.52, 95% CI=1.26-1.84; for TT vs. CT+CC: OR=1.42, 95% CI=1.19-1.70; for TT+CT versus CC: OR=1.46, 95%CI=1.05-2.04). In addition, the results indicated that T allele had the positive association which was driven by East-asian populations (random: OR=1.44, 95% CI=1.2-1.74; fixed: OR=1.39, 95% CI=1.20-1.61), Middle-eastern populations (random: OR=1.30, 95% CI=1.05-1.63; fixed: OR=1.30, 95% CI=1.05-1.63) and Mixed-race (random: OR=1.96, 95% CI=1.35-2.85; fixed: OR=1.31, 95% CI=1.20-1.43). CONCLUSION: This meta-analysis suggests that MTHFR C677T polymorphism is associated with male infertility.


Assuntos
Infertilidade Masculina/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único/genética , Alelos , Estudos de Casos e Controles , Ácido Fólico/metabolismo , Humanos , Masculino , Fatores de Risco
16.
Phytochemistry ; 136: 81-93, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28110957

RESUMO

Eleven highly halogenated chamigrane sesquiterpenoids, compositacins A-K, including one unusual rearranged chamigrane sesquiterpenoid, compositacin A, were isolated from the red alga Laurencia composita Yamada, along with seven known structural analogues. Compositacins B and D are the first examples of chamigranes bearing an ether bridge involving C-5/C-9 and C-3/C-5, respectively, while compositacins B and C represent the first chamigranes with a C-10 carbonyl group. Their structures were elucidated on the basis of extensive spectroscopic analysis. The absolute configuration of compositacin B was determined by ECD calculation, whereas the absolute configurations of compositacins A and C-L were proposed on biosynthetic grounds by comparison to compositacin B and the related known sesquiterpenoids johnstonol and yicterpene A. We also suggest that the structure of the previously reported sesquiterpenoid laurokamin A should be revised. Cytotoxicity and antifungal activity of these isolates were also investigated. The results showed that compositacin G exhibited good antifungal activity against Microsporum gypseum (Cmccfmza) with a MIC80 value of 4 µg/mL relative to positive controls. Four of the chamigrane halosesquiterpenoids showed marginal cytotoxicity against the A-549 human lung adenocarcinoma cell line with IC50 values ranging from 48.6 to 85.2 µM.


Assuntos
Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Hidrocarbonetos Halogenados/isolamento & purificação , Hidrocarbonetos Halogenados/farmacologia , Laurencia/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Antifúngicos/química , Antineoplásicos/química , Linhagem Celular , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Hidrocarbonetos Halogenados/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Sesquiterpenos/química
17.
Springerplus ; 5(1): 1963, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27900237

RESUMO

Location based services (LBS) provided by wireless sensor networks have garnered a great deal of attention from researchers and developers in recent years. Chirp spread spectrum (CSS) signaling formatting with time difference of arrival (TDOA) ranging technology is an effective LBS technique in regards to positioning accuracy, cost, and power consumption. The design and implementation of the location engine and location management based on TDOA location algorithms were the focus of this study; as the core of the system, the location engine was designed as a series of location algorithms and smoothing algorithms. To enhance the location accuracy, a Kalman filter algorithm and moving weighted average technique were respectively applied to smooth the TDOA range measurements and location results, which are calculated by the cooperation of a Kalman TDOA algorithm and a Taylor TDOA algorithm. The location management server, the information center of the system, was designed with Data Server and Mclient. To evaluate the performance of the location algorithms and the stability of the system software, we used a Nanotron nanoLOC Development Kit 3.0 to conduct indoor and outdoor location experiments. The results indicated that the location system runs stably with high accuracy at absolute error below 0.6 m.

18.
Shanghai Kou Qiang Yi Xue ; 25(2): 191-4, 2016 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-27329883

RESUMO

PURPOSE: To compare the shaping ability of three rotary Ni-Ti instruments in simulated root canals. METHODS: A total of 30 simulated resin blocks were divided randomly into 3 groups: ProTaper Universal, ProTaper Next and TF Adaptive. Each group consisted of 10 root canals. The preparation time and changes in canal curvature were measured. Pre- and post-instrumentation photograghs were taken by precise camera and superimposed through Photoshop. The material removed from the inner and outer canal walls at 9 points beginning at 0 mm from the foramen were measured with Image Pro Plus. Centering ability was determined accordingly. The data was analyzed with SPSS13.0 software package. RESULTS: During root canal preparation, no instruments fractured. ProTaper Next was much faster than ProTaper Universal(P<0.05). At the apical curvature, transportation was the least with TF Adaptive, followed by Protaper Next (P<0.05). There were no significant differences in 3 groups with respect to coronal curvature transportation (P>0.05). CONCLUSIONS: Under the conditions of this study, ProTaper Next was the most efficient instrument. TF Adaptive and Protaper Next showed better shaping ability. In general, all the instruments respected original canal curvature well and were safe to be used.


Assuntos
Instrumentos Odontológicos , Cavidade Pulpar , Níquel/química , Preparo de Canal Radicular/métodos , Titânio/química , Humanos
19.
Toxicol Ind Health ; 32(11): 1882-1890, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26229097

RESUMO

Formaldehyde (FA), a ubiquitous environmental pollutant, has long been suspected of causing adverse male reproductive effects. However, the molecular and cellular mechanisms underlying this phenomenon remain elusive. The overall aim of this study is to clarify the role of mammalian target of rapamycin (mTOR) in male reproductive injuries induced by FA exposure, by which we can further understand the molecular mechanism of FA male reproductive toxicity. In this study, immunohistochemistry, Western blotting, and reverse transcription polymerase chain reaction analysis were used to detect the expression of mTOR molecule in testicular tissues. We found that FA exposure inhibits the expression of mTOR in a dose-dependent manner. Combined with our earlier finding, we found the decreasing expression of mTOR in testicular tissue were consistent with the changes of testicular structure and autophagy levels. In summary, our data suggested that mTOR molecule might be involved in male reproductive injuries induced by FA exposure.

20.
Genome Announc ; 2(5)2014 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-25278535

RESUMO

Burkholderia pyrrocinia strain Lyc2 was isolated from the tobacco rhizosphere in China. This bacterium exhibits a remarkable capacity to inhibit the growth of multiple pathogens and shows strong suppression of cotton seedling damping-off. Here, we present the draft genome sequence of Burkholderia pyrrocinia strain Lyc2.

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