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1.
J Opt Soc Am A Opt Image Sci Vis ; 40(3): 427-442, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37133009

RESUMO

The offset linear canonical transform (OLCT) is an important research topic in many fields, and it has a more universal and elastic performance due to its extra parameters. However, although much work has been done concerning the OLCT, its fast algorithms are rarely addressed. In this paper, an O(N log⁡N) fast OLCT (FOLCT) algorithm that can significantly reduce the amount of calculation and improve accuracy is proposed. First, the discrete form of the OLCT is provided, and several important properties of its kernel are advanced. Next, the FOLCT based on the fast Fourier transform (FT) is derived for its numerical implementation. Then, the numerical results indicate that the FOLCT is a serviceable tool for signal analysis; additionally, the FOLCT algorithm can be used for the FT, fractional FT, linear canonical transform, and other transforms. Finally, its application to the detection of linear frequency modulated signals and optical image encryption, which is a basic case in signal processing, is discussed. The FOLCT can be effectively applied for the fast numerical calculation of the OLCT with valid and accurate results.

2.
Zhongguo Zhen Jiu ; 40(12): 1319-21, 2020 Dec 12.
Artigo em Chinês | MEDLINE | ID: mdl-33415875

RESUMO

The pivot effect of Tianshu (ST 25) was analyzed, which was explored from 5 aspects, named the ascending and descending of spleen and stomach qi, the smooth flowing of liver and gallbladder, the transmission of intestine, the passage regulation of three jiao (triple energizer) and conducting yang from yin. Tianshu (ST 25) governs qi and is in charge of its ascending, descending, exiting and entering. In order to understand the effect and application of such acupoint, the theoretic source should be interpreted at first. Hence, the exploration on the pivot effect of Tianshu (ST 25) in terms of the ascending, descending, exiting and entering of qi activity may provide the guidance to the clinical treatment.


Assuntos
Pontos de Acupuntura , Baço , Fígado , Estômago
3.
Anal Chim Acta ; 1063: 82-90, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-30967189

RESUMO

In this study, a novel automatic analytical methodology using a titanium dioxide (TiO2)-assisted preconcentration/on-site vapor-generation (VG) chip hyphenated with inductively coupled plasma-mass spectrometry (ICP-MS) for online determination of mercuric ions (Hg2+) was developed. Interestingly, the TiO2 nanoparticle (nano-TiO2) coating on the channel surface acted not only as a sorbent for preconcentration but also as a catalyst for photocatalyst-assisted VG. Under optimum operation conditions, the developed method was validated by analyzing the certified reference material (CRM) Seronorm™ Trace Elements Urine L-2 (freeze-dried human urine). Based on the obtained results, the dramatic reduction of "hands-on" manipulation and the elimination of hazardous materials (e.g., sodium borohydride (NaBH4) and stannous chloride (SnCl2)) from the process enabled a simple and ultraclean procedure with an extremely low detection limit of 0.75 ng L-1 for Hg2+ in urine samples. To the best of our knowledge, this is the first study to report the direct exploitation of a nano-TiO2-coated microfluidic device for online sample preconcentration and on-site VG prior to ICP-MS measurement.


Assuntos
Mercúrio/urina , Titânio/química , Humanos , Íons/urina , Espectrometria de Massas/instrumentação , Volatilização
4.
Int J Nanomedicine ; 13: 3177-3188, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29922054

RESUMO

INTRODUCTION: Stimulating the proliferation and differentiation of chondrocytes for the regeneration of articular cartilage is a promising strategy, but it is currently ineffective. Although both physical stimulation and growth factors play important roles in cartilage repair, their interplay remains unclear and requires further investigation. In this study, we aimed to clarify their contribution using a magnetic drug carrier that not only can deliver growth factors but also provide an external stimulation to cells in the two-dimensional environment. MATERIALS AND METHODS: We developed a nanocapsule (transforming growth factor-ß1 [TGF-ß1]-loaded magnetic amphiphilic gelatin nanocapsules [MAGNCs]; TGF-ß1@MAGNCs) composed of hexanoic-anhydride-grafted gelatin and iron oxide nanoparticles to provide a combination treatment of TGF-ß1 and magnetically induced physical stimuli. With the expression of Arg-Gly-Asp peptide in the gelatin, the TGF-ß1@MAGNCs have an inherent affinity for chondrogenic ATDC5 cells. RESULTS: In the absence of TGF-ß1, ATDC5 cells treated with a magnetic field show significantly upregulated Col2a1 expression. Moreover, TGF-ß1 slowly released from biodegradable TGF-ß1@ MAGNCs further improves the differentiation with increased expression of Col2a1 and Aggrecan. CONCLUSION: Our study shows the time-dependent interplay of physical stimuli and growth factors on chondrogenic regeneration, and demonstrates the promising use of TGF-ß1@MAGNCs for articular cartilage repair.


Assuntos
Condrócitos/citologia , Condrogênese/efeitos dos fármacos , Nanocápsulas/química , Fator de Crescimento Transformador beta1/farmacocinética , Agrecanas/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Condrócitos/efeitos dos fármacos , Condrogênese/fisiologia , Colágeno Tipo II/metabolismo , Gelatina/química , Humanos , Campos Magnéticos , Camundongos , Oligopeptídeos/química , Engenharia Tecidual/métodos , Fator de Crescimento Transformador beta1/genética
5.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 36(2): 149-54, 2016 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-27078988

RESUMO

OBJECTIVE: To observe the efficacy and safety of modified Shengma Biejia Decoction (MSBD) combined with CAG program in treating elderly acute myeloid leukemia (AML) patients with yin deficiency toxin stasis syndrome (YDTSS). METHODS: Totally 46 elderly AML patients were assigned to the treatment group (24 cases; treated with MSBD + CAG) and the control group (22 cases; treated with CAG + placebos of Chinese medicine) according to random digit table. The therapeutic course of CM placebo or MSBD was 21 days. The clinical efficacy and adverse reactions were observed. Meanwhile, physical state (ECOG Score), transfusion dependency, and TCM syndrome score were compared before and after treatment. RESULTS: (1) The complete remission rate was 54% (13/24) and the objective response rate (ORR) was 71% (17/24) in the treatment group, obviously higher than those of the control group [36% (8/22); 54% (13/24)], with statistical difference (P = 0.036, 0.042). When comparing the efficacy based on risk level, the moderate and poor ORR was 71% (10/14) and 67% (6/9) in the treatment group, and 57% (8/14) and 33% (2/6) in the control group, with statistical difference between the two groups (P = 0.048; P = 0.010). (2) Compared with before treatment in the same group, the ECOG score significantly decreased, the average infusion time of red cells and platelets were markedly prolonged in the treatment group after treatment (P < 0.05). ECOG score, the average infusion time of red cells and platelets were significantly better in the treatment group than in the control group after treatment (P < 0.05). (3) Compared with before treatment in the same group, scores of fever, hemorrhage, and bone pain were markedly reduced in the control group (P < 0.05); scores of fever, fatigue, hemorrhage, dry mouth, and bone pain were markedly reduced in the treatment group (P < 0.05). Better effect in relief of fever, fatigue, hemorrhage, dry mouth, and so on was obtained in the treatment group than in the control group (P < 0.05). (4) In aspect of hematotoxicity, the incidence of neutropenia, anemia, thrombocytopenia was obviously lower in the treatment group than in the control group [29.2% (7/24) vs 54.5% (12/22); 16.7% (4/ 24) vs 45.5% (10/22); 33.3% (8/24) vs 63.6% (14/22); P < 0.05]. The incidence of fatigue and anorexia was obviously lower in the treatment group than in the control group [37.5% (9/24) vs 63.6% (14/22), 37.5% (9/24) vs 81.8% (18/22); P < 0.05]. CONCLUSION: MSBD combined with CAG program in treating elderly AML patients with YDTSS, with efficacy enhancing toxicity reducing effect, had distinct advantages in improving physical condition and clinical symptoms, and reducing transfusion dependency.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Fitoterapia , Deficiência da Energia Yin/tratamento farmacológico , Aclarubicina/uso terapêutico , Idoso , Citarabina/uso terapêutico , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Medicina Tradicional Chinesa
6.
J Control Release ; 220(Pt A): 107-118, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26478017

RESUMO

We developed a surfactant-free method utilizing amifostine to stably link a targeting ligand (Herceptin) to amphiphilic gelatin (AG)-iron oxide@calcium phosphate (CaP) nanoparticles with hydrophobic curcumin (CUR) and hydrophilic doxorubicin (DOX) encapsulated in the AG core and CaP shell (AGIO@CaP-CD), respectively. This multi-functional nanoparticle system has a pH-sensitive CaP shell and degradable amphiphilic gelatin (AG) core, which enables controllable sequential release of the two drugs. The dual-targeting system of AGIO@CaP-CD (HER-AGIO@CaP-CD) with a bioligand and magnetic targeting resulted in significantly elevated cellular uptake in HER2-overexpressing SKBr3 cells and more efficacious therapy than delivery of targeting ligand alone due to the synergistic cell multi-drug resistance/apoptosis-inducing effect of the CUR and DOX combination. This nanoparticle combined with Herceptin and iron oxide nanoparticles not only provided a dual-targeting functionality, but also encapsulated CUR and DOX as a dual-drug delivery system for the combination therapy. This study further demonstrated that the therapeutic efficacy of this dual-targeting co-delivery system can be improved by modifying the application duration of magnetic targeting, which makes this combination therapy system a powerful new tool for in vitro/in vivo cancer therapy, especially for HER2-positive cancers.


Assuntos
Amifostina/química , Fosfatos de Cálcio/química , Curcumina/administração & dosagem , Doxorrubicina/administração & dosagem , Gelatina/química , Magnetismo , Nanopartículas/química , Receptor ErbB-2/análise , Animais , Preparações de Ação Retardada , Feminino , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Camundongos
7.
Anal Chem ; 85(21): 10091-8, 2013 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-24063353

RESUMO

We developed a selective and sensitive hyphenated system employing a microfluidic-based vapor generation (VG) system in conjunction with high-performance liquid chromatography (HPLC) separation and inductively coupled plasma-mass spectrometry (ICPMS) detection for the determination of trace inorganic selenium (Se) species. The VG system exploited poly(methyl methacrylate) (PMMA) substrates of high optical quality to fabricate a microfluidic-based photocatalyst-assisted reduction device (microfluidic-based PCARD). Moreover, to reduce the consumption of photocatalysts during analytical procedures, a microfluidic-based PCARD coated with titanium dioxide nanoparticles (nano-TiO2) was employed to avoid consecutive loading. Notably, to simplify the coating procedure and improve the stability of the coating materials, a dynamic coating method was utilized. Under the optimized conditions for the selenicals of interest, the online HPLC/TiO2-coated microfluidic-based PCARD/ICPMS system enabled us to achieve detection limits (based on 3σ) of 0.043 and 0.042 µg L(-1) for Se(IV) and Se(VI), respectively. Both Se(IV) and Se(VI) could be efficiently vaporized within 15 s, while a series of validation experiments indicated that our proposed method could be satisfactorily applied to the determination of inorganic Se species in the environmental water samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Microfluídica/instrumentação , Selênio/análise , Titânio/química , Microscopia Eletrônica de Varredura
8.
Dalton Trans ; 40(31): 7898-907, 2011 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-21725547

RESUMO

The potential energy surfaces for the chemical reactions of group 14 carbenes have been studied using density functional theory (B3LYP/LANL2DZ). Five saturated five-membered-ring N-heterocyclic carbene Dipp[upper bond 1 start]N(CH(2))(2)N(Dipp)E[upper bond 1 end]: (five-ring-E:) species, where E = C, Si, Ge, Sn and Pb, have been chosen as model reactants in this work. Also, four kinds of chemical reactions; addition of water, methane insertion, alkene cycloaddition and dimerization, have been used to study the chemical reactivities of these group 14 carbenes. The present theoretical investigations suggest that the relative carbenic reactivity decreases in the order: C > Si > Ge > Sn > Pb. That is, the heavier the group 14 atom (E), the more stable is the carbene towards chemical reactions. This may be the reason that there have been many instances reported of the synthesis and characterization of stable group 14 five-membered-ring N-heterocyclic carbene species with various alkyl protecting substituents at room temperature. Furthermore, the singlet-triplet energy splitting of the five-ring-E:, as described in the configuration mixing model attributed to the work of Pross and Shaik, can be used as a diagnostic tool to predict their reactivities. The results obtained allow a number of predictions to be made.

9.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 18(4): 1036-41, 2010 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-20723324

RESUMO

The objective of this study was to explore the differences between refractory anemia with ringed sideroblast (RARS) and RARS associated with marked thrombocytosis (RARS-T) in the clinical, biological features and prognosis. The morphological changes of cells were observed by bone marrow smear and biopsy. Immunologic phenotype was analyzed by flow cytometry, and chromosome was examined by conventional chromosomal analysis. JAK2 V617F and MPL W515L mutations were screened by allele-specific polymerase chain reaction (AS-PCR) and sequence analysis. The results showed that this case was clinically diagnosed as RARS with thrombophilia, the level of serum potassium was positively related with platelet counts. When platelets increased, the clusters of atypical giant platelets and megakaryocytes were observed in peripheral blood and bone marrow examined by bone marrow smear and bone marrow biopsy respectively, JAK2 V617F and MPL W515L mutations were negative. It is concluded that RARS may transform into RARS-T accompanied with megakaryocyte proliferation, large atypical platelets and negative JAK2 V617F. Preventing thrombophilia and monitoring relative gene mutations are necessary when atypical giant platelets and fluctuant platelet counts occurred in process of RARS with tendency to RARS-T.


Assuntos
Anemia Refratária/metabolismo , Anemia Refratária/patologia , Anemia Sideroblástica/patologia , Plaquetas/patologia , Idoso , Anemia Refratária/diagnóstico , Anemia Sideroblástica/diagnóstico , Feminino , Humanos , Contagem de Plaquetas , Trombocitose/patologia
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