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1.
J Biophotonics ; : e201900242, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31804752

RESUMO

Development of label-free methods for accurate classification of cells with high throughput can yield powerful tools for biological research and clinical applications. We have developed a deep neural network of DINet for extracting features from cross-polarized diffraction image (p-DI) pairs on multiple pixel scales to accurately classify cells in five types. A total of 6185 cells were measured by a polarization diffraction imaging flow cytometry (p-DIFC) method followed by cell classification with DINet on p-DI data. The averaged value and SD of classification accuracy were found to be 98.9% ± 1.00% on test data sets for 5-fold training and test. The invariance of DINet to image translation, rotation, and blurring has been verified with an expanded p-DI data set. To study feature-based classification by DINet, two sets of correctly and incorrectly classified cells were selected and compared for each of two prostate cell types. It has been found that the signature features of large dissimilarities between p-DI data of correctly and incorrectly classified cell sets increase markedly from convolutional layers 1 and 2 to layers 3 and 4. These results clearly demonstrate the importance of high-order correlations extracted at the deep layers for accurate cell classification.

2.
Macromol Biosci ; 19(4): e1800478, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30694599

RESUMO

The use of natural compounds to construct biomaterials, including delivery system, is an attractive strategy. In the present study, through threading functional α-cyclodextrins onto the conjugated macromolecules of poly(ethylene glycol) (PEG) and natural compound bile acid, glycopolymers of polyrotaxanes with the active targeting ability are obtained. These glycopolymers self-assemble into micelles as evidenced by dynamic light scattering and transmission electron microscopy, in which glucosamine, as an example of targeting groups, is introduced. These micelles after loading doxorubicin (DOX) exhibit the selective recognition with cancer cells 4T1. Meanwhile, the maximal half inhibitory concentration is determined to be ≈2.5 mg L-1 for the DOX-loaded micelles, close to the value of free DOX·HCl (1.9 mg L-1 ). The cumulative release of DOX at pH 5.5 is faster than at pH 7.4, which may be used as the controlled release system. This drug delivery system assembled by glycopolymers features high drug loading of DOX, superior biocompatibility. The strategy not only utilizes the micellization induced by bile acids, but also overcomes the major limitation of PEG such as the lack of targeting groups. In particular, this drug delivery platform can extend to grafting the other targeting groups, rendering this system more versatile.


Assuntos
Ácidos e Sais Biliares , Doxorrubicina , Portadores de Fármacos , Micelas , Neoplasias Experimentais/tratamento farmacológico , Rotaxanos , Animais , Ácidos e Sais Biliares/química , Ácidos e Sais Biliares/farmacocinética , Ácidos e Sais Biliares/farmacologia , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Camundongos , Células NIH 3T3 , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Coelhos , Rotaxanos/química , Rotaxanos/farmacocinética , Rotaxanos/farmacologia
3.
Biomed Opt Express ; 9(5): 2081-2094, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29760971

RESUMO

A new and noncontact approach of multispectral reflectance imaging has been developed to inversely determine the absorption coefficient of µ a , the scattering coefficient of µs and the anisotropy factor g of a turbid target from one measured reflectance image. The incident beam was profiled with a diffuse reflectance standard for deriving both measured and calculated reflectance images. A GPU implemented Monte Carlo code was developed to determine the parameters with a conjugate gradient descent algorithm and the existence of unique solutions was shown. We noninvasively determined embedded region thickness in heterogeneous targets and estimated in vivo optical parameters of nevi from 4 patients between 500 and 950nm for melanoma diagnosis to demonstrate the potentials of quantitative reflectance imaging.

4.
Biomacromolecules ; 19(2): 626-632, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-29341595

RESUMO

Poly(vinyl alcohol) (PVA) is a cytocompatible synthetic polymer and has been commonly used to prepare hydrogels. Bile acids and ß-cyclodextrin are both natural compounds and they form stable host-guest inclusion complexes. They are attached covalently onto a low molecular weight PVA separately. Self-healing hydrogels can be easily formed by mixing the aqueous solutions of these PVA based polymers. The mechanical properties of the hydrogels can be tuned by varying the molar fractions of bile acid units on PVA. The dynamic inclusion complexation of the host-guest pair of the hydrogel allows the self-healing rapidly under ambient atmosphere and their mechanical properties could recover their original values in 1 min after incision. These PVA based polymers exhibited the good cytocompatibility and high hemocompatibility as shown by their biological evaluations. The use of natural compounds for host-guest interaction make such gels especially convenient to use as biomaterials, an advantage over conventional hydrogels prepared through freeze-thaw method.


Assuntos
Fibroblastos/metabolismo , Hidrogel de Polietilenoglicol-Dimetacrilato , Teste de Materiais , Álcool de Polivinil , beta-Ciclodextrinas , Animais , Fibroblastos/citologia , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Camundongos , Álcool de Polivinil/química , Álcool de Polivinil/farmacologia , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacologia
5.
Nat Prod Commun ; 8(12): 1715-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24555280

RESUMO

Two new compounds, (2R,3R,4R)-3',5'-dimethoxy-3,4,7,4'-tetrahydroxy-flavan (1) and 2-(4-hydroxy-3-methoxybenzoyl)-4-methoxy-benzaldehyde (2), together with 35 known phenolic compounds were obtained from the fruits of Amomum tsao-ko. Structures of the new compounds were elucidated on the basis of spectroscopic means, including 2D NMR, a n d high-resolution M S analysis. The isolated compounds were tested in vitro for t heircomplement-inhibitory properties against the classical pathway (CP) and alternative pathway (AP). The results showed that 14 compounds exhibited anti-complementary activities against the CP and AP with CH50 values of 0.42 - 4.43 mM and AP50 values of 0.53 -1.51 mM. Preliminary mechanism studies showed that 1,7-bis(4-hydroxyphenyl)-4(E)-hepten-3-one (8) blocked C1q, C2, C3, C4, C5 and C9 components of the complement system, and hydroquinone (15) acted on C1q, C2, C3, C5 and C9 components.


Assuntos
Amomum/química , Benzaldeídos/isolamento & purificação , Inativadores do Complemento/isolamento & purificação , Flavonoides/isolamento & purificação , Animais , Benzaldeídos/química , Medicamentos de Ervas Chinesas/química , Flavonoides/química , Frutas/química , Humanos , Masculino , Estrutura Molecular , Plantas Medicinais/química , Coelhos , Ovinos
6.
Zhonghua Liu Xing Bing Xue Za Zhi ; 31(3): 300-3, 2010 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-20510058

RESUMO

OBJECTIVE: To better understand the epidemiology of rabies during the past ten years in Yancheng city, Jiangsu province. METHODS: Data was collected and analyzed on rabies cases in Yancheng. Density and vaccination rate on Canine, Rate of injured people bit by dogs, and the information of post-exposure prophylaxis were studied. Rabies virus in the dog brains, collected around the epidemic areas of Yancheng, were detected and analyzed. RESULTS: A total of 135 human rabies cases occurred from 1999 through 2008, and formed the second epidemic peak since 1958. Of these victims, 84% (114) were farmers. In general, the rate of people having dogs were 3% - 6% per 100 people, and the injured person-times of 100 dogs were 6.37 per year. Notably, the vaccination rate of dogs was only 20%. Of those people injured by dogs and other animals, 77% had received post-exposure treatment, and only 5% - 10% had been administered anti-rabies serum. Rabies virus antigen was found in 4 (3.6%) of 111 brain specimens among dogs collected from epidemic areas. Genetic analysis of N and G genes, which were amplified from brain specimens, indicated that these viruses belong to genotype I rabies and expressing a close relationship with the Chinese vaccine strain CTN. CONCLUSION: The large number of dogs with low vaccination rate among them, together with the incorrect and low post-exposure treatment in rural areas seemed to be responsible for the outbreak of rabies in Yancheng city.


Assuntos
Mordeduras e Picadas/epidemiologia , Raiva/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , China/epidemiologia , Doenças do Cão/epidemiologia , Cães , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Profilaxia Pós-Exposição , Vírus da Raiva/genética , Vírus da Raiva/imunologia , Adulto Jovem
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