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1.
Opt Lett ; 48(23): 6232-6235, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039234

RESUMO

It is attractive to use an optical nanorouter by artificial nanostructures to substitute the traditional Bayer filter for an image array sensor, which, however, poses great challenges in balancing the design strategy and the ease of fabrication. Here, we implement and compare two inverse design schemes for rapid optimization of RGGB Bayer-type optical nanorouter. One is based on the multiple Mie scattering theory and the adjoint gradient that is applicable to arrays of nanospheres with varying sizes, and the other is based on the rigorous coupled wave analysis and the genetic algorithm. In both cases, we study layered nanostructures that can be efficiently modeled respectively which greatly accelerates the inverse design. It is shown that the color-dependent peak collection efficiencies of nanorouters designed in the two methods for red, green, and blue wavelengths reach 37%, 44%, and 45% and 52%, 50%, and 66%, respectively. We further demonstrate color nanorouters that provide light focusing to four quadrants working in both the visible and infrared bands, which promises multispectral imaging applications.

2.
BMC Infect Dis ; 20(1): 168, 2020 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-32087697

RESUMO

BACKGROUND: Respiratory tract infection (RTI) in young children is a leading cause of morbidity and hospitalization worldwide. There are few studies assessing the performance for bronchoalveolar lavage fluid (BALF) versus oropharyngeal swab (OPS) specimens in microbiological findings for children with RTI. The primary purpose of this study was to compare the detection rates of OPS and paired BALF in detecting key respiratory pathogens using suspension microarray. METHODS: We collected paired OPS and BALF specimens from 76 hospitalized children with respiratory illness. The samples were tested simultaneously for 8 respiratory viruses and 5 bacteria by suspension microarray. RESULTS: Of 76 paired specimens, 62 patients (81.6%) had at least one pathogen. BALF and OPS identified respiratory pathogen infections in 57 (75%) and 49 (64.5%) patients, respectively (P > 0.05). The etiology analysis revealed that viruses were responsible for 53.7% of the patients, whereas bacteria accounted for 32.9% and Mycoplasma pneumoniae for 13.4%. The leading 5 pathogens identified were respiratory syncytial virus, Streptococcus pneumoniaee, Haemophilus influenzae, Mycoplasma pneumoniae and adenovirus, and they accounted for 74.2% of etiological fraction. For detection of any pathogen, the overall detection rate of BALF (81%) was marginally higher than that (69%) of OPS (p = 0.046). The differences in the frequency distribution and sensitivity for most pathogens detected by two sampling methods were not statistically significant. CONCLUSIONS: In this study, BALF and OPS had similar microbiological yields. Our results indicated the clinical value of OPS testing in pediatric patients with respiratory illness.


Assuntos
Líquido da Lavagem Broncoalveolar/microbiologia , Líquido da Lavagem Broncoalveolar/virologia , Criança Hospitalizada , Testes Diagnósticos de Rotina/métodos , Orofaringe/microbiologia , Orofaringe/virologia , Infecções Respiratórias/diagnóstico , Criança , Pré-Escolar , Feminino , Hospitalização , Humanos , Lactente , Recém-Nascido , Masculino , Infecções Pneumocócicas/diagnóstico , Infecções Pneumocócicas/microbiologia , Infecções por Vírus Respiratório Sincicial/diagnóstico , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano/genética , Vírus Sincicial Respiratório Humano/isolamento & purificação , Infecções Respiratórias/microbiologia , Infecções Respiratórias/virologia , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/isolamento & purificação
3.
Biochim Biophys Acta ; 1820(7): 1021-6, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22353334

RESUMO

BACKGROUND: Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear receptors superfamily and are transcription factors activated by specific ligands. Liver X receptors (LXR) belong to the nuclear hormone receptors and have been shown to play an important role in cholesterol homeostasis. From the previous screening of several medicinal plants for potential partial PPARγ agonists, the extracts of Cornus alternifolia were found to exhibit promising bioactivity. In this paper, we report the isolation and structural elucidation of four new compounds and their potential as ligands for PPAR. METHODS: The new compounds were extracted from the leaves of C. alternifolia and fractionated by high-performance liquid chromatography. Their structures were elucidated on the basis of spectroscopic evidence and analysis of their hydrolysis products. RESULTS: Three new iridoid glycosides including an iridolactone, alternosides A-C (1-3), a new megastigmane glycoside, cornalternoside (4) and 10 known compounds, were obtained from the leaves of C. alternifolia. Kaempferol-3-O-ß-glucopyranoside (5) exhibited potent agonistic activities for PPARα, PPARγ and LXR with EC50 values of 0.62, 3.0 and 1.8 µM, respectively. CONCLUSIONS: We isolated four new and ten known compounds from C. alternifolia, and one known compound showed agonistic activities for PPARα, PPARγ and LXR. GENERAL SIGNIFICANCE: Compound 1 is the first example of a naturally occurring iridoid glycoside containing a ß-glucopyranoside moiety at C-6.


Assuntos
Proliferação de Células/efeitos dos fármacos , Cornus/química , Glicosídeos Iridoides/farmacologia , Receptores Nucleares Órfãos/agonistas , Receptores Ativados por Proliferador de Peroxissomo/agonistas , Extratos Vegetais/farmacologia , Animais , Células CHO , Cricetinae , Células Hep G2 , Humanos , Glicosídeos Iridoides/química , Receptores X do Fígado , Extratos Vegetais/química
4.
Chem Biodivers ; 8(11): 2104-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22083922

RESUMO

A novel diterpene alkaloid named honatisine (1) has been isolated from the whole plants of Delphinium honanense, along with six known alkaloids, siwanine E (2), isoatisine (3), atisine (4), delcorinine (5), uraphine (6), and nordhagenine A (7). Their structures were deduced on the basis of their spectral data. All of them were evaluated by a SRB assay for their cytotoxicity, and compound 1 showed a significant cytotoxic activity (IC(50) =3.16 µM) against the MCF-7 cell line.


Assuntos
Alcaloides/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Delphinium/química , Diterpenos/isolamento & purificação , Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , China , Delphinium/crescimento & desenvolvimento , Diterpenos/farmacologia , Humanos , Concentração Inibidora 50 , Estrutura Molecular
5.
J Pharm Anal ; 1(1): 57-59, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29403683

RESUMO

The chemical constituents from Aconitum richardsonianum var. pseudosessiliflorum were investigated. The roots of this plant were extracted three times with 90% EtOH at the room temperature. The ethanol extracts were combined and concentrated under reduced pressure to yield residue, which was suspended in water and successively partitioned with chloroform. The chloroform extraction was isolated and purified by silica gel and Sephadex LH-20 column chromatography. Six compounds were isolated and elucidated as delelatine (1), isodelpheline (2), 3-acetylaconitine (3), isoatisine (4), nordhagenine A (5) and yunaconitine (6). Compounds 1-5 were obtained from Aconitum Brunneum for the first time. Compound (1) showed significant cytotoxic activities (IC50= 4.36 µM) against the human tumor cell line P388.

6.
Fitoterapia ; 81(7): 929-31, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20550959

RESUMO

A new diterpene alkaloid named delphatisine C (1) has been isolated from aerial parts of Delphinium chrysotrichum along with three known norditerpenoid alkaloids delpheline (2), delbrunine (3), and delectinine (4). Their structures were characterized on the basis of their spectral data. All of them were determined by SRB assay for their cytotoxicity, and compound (1) showed significant cytotoxic activities (IC(50)=2.36 µmol/L) against the A549 cell line.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Delphinium/química , Diterpenos/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Humanos , Estrutura Molecular , Componentes Aéreos da Planta , Extratos Vegetais/química , Extratos Vegetais/farmacologia
7.
Yao Xue Xue Bao ; 43(9): 934-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19048785

RESUMO

To investigate the chemical constituents of the roots of Aconitum taipaicum, silica gel column chromatography was used for the isolation and purification of compounds. A new norditerpenoid alkaloid, isodelelatine (1), along with five known alkaloids, atisine (2), delfissinol (3), liangshanine (4), hypaconitine (5) and delelatine (6) were isolated and identified. The structure of the new compound was elucidated on the basis of spectral data.


Assuntos
Aconitina/análogos & derivados , Aconitum/química , Alcaloides/química , Diterpenos/química , Aconitina/química , Aconitina/isolamento & purificação , Estrutura Molecular , Raízes de Plantas/química , Plantas Medicinais/química
8.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 1): m107, 2008 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-21581473

RESUMO

In the neutral title complex, [Fe(C(6)H(5)N(2)O(2))(2)(H(2)O)(2)], the coordination geometry aound the Fe(II) atom, which lies on an inversion centre, is distorted octa-hedral comprising two N atoms and two O atoms from two 5-methyl-pyrazine-2-carboxyl-ate ligands, and two water mol-ecules. The crystal structure is stabilized by a network of O-H⋯O hydrogen bonds, resulting in a two-dimensional supra-molecular structure.

9.
Zhongguo Zhong Yao Za Zhi ; 33(23): 2784-6, 2008 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-19260311

RESUMO

OBJECTIVE: To study the chemical constituents from Delphinium honanense var. piliteram. METHOD: The constituents were isolated and purified with chromatographic methods, identified by NMR, MS and IR. RESULT: Six compounds were isolated and elucidated as siwanine E (1), isoatisine (2), 12-epi-napelline (3), acontine (4), ajadelphinine (5) and beta-sitosterol (6). CONCLUSION: Compounds 1-6 are all isolated from the plant for the first time.


Assuntos
Delphinium/química , Plantas Medicinais/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação
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