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1.
Nanomaterials (Basel) ; 9(7)2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31261670

RESUMO

With the developments in high-performance nano-insulation material technology, theoretical studies on the heat transfer mechanisms in these materials have been conducted. However, the conductivity of nanometer-sized skeletons is still unclear. It is necessary to clarify the thermal conductivity of nanometer-sized solid skeletons in order to better understand the heat transfer mechanisms in nano-insulation materials. In the present study, a theoretical model for the thermal conductivity of nanometer-sized skeletons in nano-insulation materials is presented based upon the meso-structure of the material and the equation of phonon transfer. The size effect in thermal conductivity of the nanometer-sized particles is studied numerically, and the thermal conductivity is theoretically obtained. At the same time, a reverse method is established for the thermal conductivity of nanometer-sized particles based on the method of particle swarm optimization (PSO). The skeleton thermal conductivity for a specific nano-insulation material with a density of 110 kg/m3 and porosity of 0.94 is identified based upon experimental data from literature. Comparison results show that the theoretical conductivity of nanometer-sized skeletons and the identified results give the values of 0.145 and 0.124 W/(m K), respectively, clearly revealing obvious an size effect in the thermal conductivity of nanometer-sized skeletons.

2.
J Ethnopharmacol ; 238: 111813, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-30910578

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Whitmania pigra Whitman (Whitmania pigra, WP), firstly recorded in the Shennong's Herbal Classic and officially listed in the Chinese Pharmacopoeia, is a well-used cardiovascular protective traditional Chinese medicine derived from leeches. Traditional Chinese physicians prefer to prescribe the dried whole body of leech processed under high temperatures. It has been reported that dried WP remains clinically effective. However, the therapeutic mechanism has yet not be clearly elucidated. AIM OF THE STUDY: This study was designed to investigate the protective activity of the extract of WP in a high-molecular-weight dextran-induced blood hyperviscosity rat model, and to explore the role of WP in improving blood hyperviscosity related metabolic disorders and to clarify the possible mechanism of metabolic regulation. MATERIALS AND METHODS: The hemorheological parameters were measured with an automated blood rheology analyzer. Hematoxylin-eosin staining was used to observe the pathological changes in aortic tissues samples. Further, a liquid chromatography-mass-spectrometry (LC-MS)-based untargeted metabolomics approach was applied to characterize the metabolic alterations. RESULTS: WP has evident attenuating effects on blood hyperviscosity and related metabolic disorders, and the influences are distinct from those of aspirin. The results showed that WP had good effects in reducing blood viscosity and ameliorating histopathological changes in the thoracic aorta in a high molecular weight dextran-induced blood hyperviscosity rat model. The middle dose (2.5 g raw material/kg body weight) of WP exhibited effects equivalent to aspirin (100 mg/kg) on hemorheological and histopathological parameters (P > 0.05). However, when using metabolomics profiling, we found that WP could significantly improve blood hyperviscosity-related metabolic disorders and restore metabolites to normal levels; while aspirin showed little effect. With principal component analysis and orthogonal partial least-squares discriminant analysis, WP regulated many more endogenous metabolites than aspirin. With pathway enrichment analysis, the differential endogenous metabolites were involved in cysteine and methionine metabolism, TCA cycle, arachidonic acid metabolism, etc., highlighting the metabolic reprogramming potential of WP against blood hyperviscosity-induced metabolic disorders. CONCLUSIONS: The study suggest that WP has a more potent effect, but a different mechanism, than aspirin in improving either blood hyperviscosity or related metabolic disorders associated with cardio- and cerebrovascular diseases.


Assuntos
Viscosidade Sanguínea/efeitos dos fármacos , Misturas Complexas/farmacologia , Sanguessugas , Animais , Ciclo-Oxigenase 2/genética , Cistationina beta-Sintase/genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Pós , Ratos Sprague-Dawley
3.
Zhongguo Zhong Yao Za Zhi ; 43(13): 2720-2725, 2018 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-30111022

RESUMO

Standard decoction of traditional Chinese medicine (TCM) is prepared by standardized process, and can be used as references to evaluate the quality of dosage forms such as decoction and dispensing granules. In order to determine the quality evaluation method for standard decoction of Chrysanthemi Flos and investigate its application, 10 batches of white chrysanthemum of Hangzhou were collected to prepare the standard decoction of white chrysanthemum of Hangzhou with standardized process parameters. Parameters such as traits, relative density, pH value, extraction ratio, transfer rate and fingerprint were selected as the indexes for quality evaluation. The established quality evaluation method for standard decoction of Chrysanthemi Flos was applied in the detection of two types of commercial Chrysanthemum dispensing granules. The results showed that the standard decoction of Chrysanthemi Flos was a clear yellow-brown aqueous solution; the relative density was 1.007-1.011; the pH value was between 5.37-5.56; the average extraction ratio was 23.6%, ranging from 19.93% to 29.69%; the average transfer ratewas 56.2% in terms of chlorogenic acid, 57.4% in terms of luteoloside and 30.6% in terms of 3,5-O-dicaffeoylquinic acid. Fingerprint similarity was between 0.864-0.989.The method showed good precision, stability and repeatability in fingerprint analysis, indicating reliable and representative results for standard decoction of Chrysanthemi Flos, and it can be used to evaluate and standardize other dosage forms.


Assuntos
Chrysanthemum , Medicamentos de Ervas Chinesas , Ácido Clorogênico , Flores , Medicina Tradicional Chinesa
4.
Molecules ; 23(2)2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-29443913

RESUMO

In acidic media, cationic phthalocyanine Alcian blue 8GX, has an efficient fluorescence quenching effect on anionic phthalocyanine tetrasulphoaluminium phthalocyanines (AlS4Pc), forming an almost non-fluorescent associate. Based on this discovery, a red-emitting fluorescent probe consisted of AlS4PC and Alcian blue 8GX has been developed through molecular assembly. Further studies indicated that the presence of Hg(II) ion has a significant fluorescence recovery effect of the probe. Notably, only Hg(II) can significantly restore the fluorescence of AlS4Pc-Alcian blue 8GX system which was revealed from the screening experiments of common metal ions, which confirmed that the fluorescence recovery by other metal ions is very weak or even unrestored, showing high specificity and sensitivity AlS4Pc-Alcian blue 8GX to Hg(II). Thus, a new fluorimetry for Hg(II) with high specificity and high sensitivity in a wide concentration range has been established using AlS4Pc-Alcian blue 8GX associate as a red-emitting fluorescent probe. It is more noteworthy that this study opens a new way for development and application of functional phthalocyanine based red-emitting fluorescent probes.


Assuntos
Azul Alciano/química , Técnicas Biossensoriais , Indóis/química , Mercúrio/isolamento & purificação , Fluorescência , Corantes Fluorescentes/química , Espectrometria de Fluorescência
5.
Chin Med Sci J ; 33(4): 252-259, 2018 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-30646989

RESUMO

Objective To assess the in vivo dynamic blood flow features of posterior optic nerve head (ONH) in rat model of nonarteritic anterior ischemic optic neuropathy (rNAION). Methods rNAION was established with Rose Bengal and argon green laser in Sprague-Dawley rats. Fundus photography and fundus fluorescein angiography (FFA) were performed to assess the dynamic changes of optic disc in morphology in 90 days and in blood perfusion in 3 hours after the induction of disease. Histological examinations were performed to evaluate the success of modeling. The dynamic blood flow kinetics of posterior ONH in rNAION were measured by Laser Doppler Flowmetry (LDF) on the day 3, 7, 14, 21, and 40 after the disease induction. One-way ANOVA, Student's t-test and Bonferroni adjustment were used for multiple comparisons of kinetic measurements of blood flow. Results Optic disc edema and subsequent resolution associated with the development of optic disc pallor were observed in rNAION. FFA showed that the optic disc was hypofluorescence in the early phase and hyperfluorescence in the late phase. Histological studies suggested edema and loosened tissues of ONH, loss of retinal ganglion cells (RGCs), optic nerve substance and gliosis. Compared to the naive rats, the blood flow kinetics of posterior ONH in rNAION significant reduced at each time point after modeling (F=175.06, P<0.0001). The reductions were specifically remarkable in 14 days after the disease induction (All P<0.01). Conclusions Continuous blood perfusion reduction was found in rNAION, with significant alteration in 14 days after disease induction. Our results provided important information for understanding the hemodynamic changes in rNAION.


Assuntos
Hemodinâmica/fisiologia , Neuropatia Óptica Isquêmica/fisiopatologia , Animais , Modelos Animais de Doenças , Angiofluoresceinografia , Humanos , Masculino , Disco Óptico/patologia , Disco Óptico/fisiopatologia , Neuropatia Óptica Isquêmica/patologia , Ratos , Ratos Sprague-Dawley , Células Ganglionares da Retina/fisiologia
6.
Artigo em Inglês | MEDLINE | ID: mdl-27366193

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is one of the most common forms of chronic liver disease. Currently, there are no recognized medical therapies effective for NAFLD. Previous studies have demonstrated the effects of total turmeric extract on rats with NAFLD induced by high-fat diet. In this study, serum metabolomics was employed using UHPLC-Q-TOF-MS to elucidate the underlying mechanisms of HFD-induced NAFLD and the therapeutic effects of TE. Supervised orthogonal partial least-squares-discriminant analysis was used to discover differentiating metabolites, and pathway enrichment analysis suggested that TE had powerful combined effects of regulating lipid metabolism by affecting glycerophospholipid metabolism, glycerolipid metabolism, and steroid hormone biosynthesis signaling pathways. In addition, the significant changes in glycerophospholipid metabolism proteins also indicated that glycerophospholipid metabolism might be involved in the therapeutic effect of TE on NAFLD. Our findings not only supply systematic insight into the mechanisms of NAFLD but also provide a theoretical basis for the prevention or treatment of NAFLD.

7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(3): 749-54, 2016 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-27400518

RESUMO

Tetrasubstituted trimethyl ammonium iodide aluminum phthalocyanine (TTMAAlPc), a positively charged phthalocyanine compound, is an emerging and potentially useful red-emitting fluorescence probe. The study showed that the fluorescence of TTMAAlPc could be quenched by RNA with high efficiency in weak alkaline media, and the degree of quenching has a linear relationship with RNA in a wide concentration range. The mechanism of quenching behavior of RNA on TTMAAlPc was discussed. It was attributed by the static interaction between RNA and TTMAAlPc, and the assembly of TTMAAlPc induced by RNA. Based on this new discovery, a novel method for quantitative determination of RNA at nanogram level has been established. The factors, including the pH of medium, buffer system, reaction time, reaction temperature, the usage of TTMAAlPc as well as the interferences, which affected the determination, were investigated and discussed. Under optimum conditions, the linear range of the calibration curve was 7.71-1 705.57 ng x mL(-1). The detection limit for RNA was 1.55 ng x mL(-1). This method has been applied to the analysis of practical samples with satisfied results. The constructed method is of high sensitivity and has a wide linear range, it also showed strong ability in the tolerance of foreign substances from anions, cations, surfactants and vitamins, all of which are common interferences encountered in the determination of RNA. Besides, it is the first report that the fluorescence quantum yield of TTMAAlPc has been measured at different pH by reference method in this work. The achieved data indicated that the fluorescence quantum yield of TTMAAlPc is larger than 20% and it keeps constant in a wide range of acidity, implying that TTMAAlPc is a high-quality red-emitting fluorescence probe, it has great potential for practical applications, thus is worthy of further study. This work expands the application of phthalocyanine compound in analytical sciences.


Assuntos
Corantes Fluorescentes , Indóis , Compostos Organometálicos , RNA/química , Limite de Detecção , Espectrometria de Fluorescência
8.
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.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(8): 2203-7, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26672294

RESUMO

Determination of chondroitin sulfate in the biomedical field has an important value. The conventional methods for the assay of chondroitin sulfate are still unsatisfactory in sensitivity, selectivity or simplicity. This work aimed at developing a novel method for sensitive and selective determination of chondroitin sulfate by fluorimetry. We found that some kinds of cationic surfactants have the ability to quench the fluorescence of tetrasulfonated aluminum phthalocyanine (AlS4Pc), a strongly fluorescent compound which emits at red region, with high efficiency. But, the fluorescence of the above-mentioned fluorescence quenching system recovered significantly when chondroitin sulfate (CS) exits. Tetradecyl dimethyl benzyl ammonium chloride(TDBAC) which was screened from all of the candidates of cationic surfactants was chosen as the quencher because it shows the most efficient quenching effect. It was found that the fluorescence of AlS4Pc was extremely quenched by TDBAC because of the formation of association complex between AlS4Pc and TDBAC. Fluorescence of the association complex recovered dramatically after the addition of chondroitin sulfate (CS) due to the ability of chondroitin sulfate to shift the association equilibrium of the association, leading to the release of AlS4Pc, thus resulting in an increase in the fluorescence of the reaction system. Based on this phenomenon, a novel method with simplicity, accuracy and sensitivity was developed for quantitative determination of CS. Factors including the reaction time, influencing factors and the effect of coexisting substances were investigated and discussed. Under optimum conditions the linear range of the calibration curve was 0.20~10.0 µg · mL(-1). The detection limit for CS was 0.070 µg · mL(-1). The method has been applied to the analysis of practical samples with satisfied results. This work expands the applications of AlS4Pc in biomedical area.


Assuntos
Sulfatos de Condroitina/análise , Corantes Fluorescentes , Ânions , Fluorescência , Fluorometria , Indóis , Limite de Detecção , Compostos Organometálicos , Espectrometria de Fluorescência , Tensoativos
10.
Dongwuxue Yanjiu ; 36(3): 152-60, 2015 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-26018858

RESUMO

Non-human primates often live in socially stable groups characterized by bonded relationships among individuals. Social organization can be used to evaluate living conditions and expansion potential. Bisexual group size, ratio of males to females and group composition are essential elements determining the type of social organization. Although the first report on Shortridge's capped langurs (Trachypithecus shortridgei) was in the 1970s, until now, the species only inhabits forests of the Dulongjiang valley in northwest Yunnan, China, with c. 250-370 individuals in 19 populations. To understand its social organization, we collected data from five groups of Shortridge's langurs at Silaluo in the Dulongjiang valley during August 2012-October 2013. Family groups consist of one adult male, 2-3 adult females and up to five young. Group size averaged 8 (7-9) individuals. The ratio of adult males to females (M/F) was 1:2.9, infants to adult females was (I/F) 1:2.2; and ratio of adults to immatures was 1:1.2, indicating the potential of a population increasing. Birth season was during March-July and the inter-birth interval was two years.


Assuntos
Cercopithecidae/psicologia , Comportamento Social , Animais , Comportamento Animal , Cercopithecidae/fisiologia , China , Ecossistema , Feminino , Masculino
11.
Int J Pharm ; 484(1-2): 181-91, 2015 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-25724135

RESUMO

The success of the oral delivery of insulin (INS) as a therapeutic protein drug would significantly improve the quality of life of diabetic patients who would otherwise receive multiple daily INS injections. The oral delivery of INS, however, is still limited in its delivery efficiency, which could be due to the chemical, enzymatic, and adsorption barriers. In this work, in an attempt to improve the delivery efficiency, the INS-loaded polymer-lipid hybrid nanoparticles (INS-PLGA-lipid-PEG NPs) were designed and constructed through a double-emulsion solvent evaporation technique, followed by formulation of the spherical micro-particles using a spray freeze dryer (SFD). This kind of dryers has a uniquely designed microfluidic aerosol nozzle (MFAN), ensuring the formation of uniform particles. The resulted particles of ∼212 µm could easily be reverted to discrete INS-PLGA-lipid-PEG NPs in an aqueous solution. The INS-PLGA-lipid-PEG NPs created in this work showed a highly negative surface charge, excellent entrapment efficiency (92.3%) and a sustained drug release (∼24 h). Confocal laser scanning microscopy and flow cytometer were used to show that the cellular uptake efficiency for the INS-PLGA-lipid-PEG NPs was more effective than the INS in Caco-2 cells. More importantly, the in vivo pharmacodynamics demonstrated that the orally delivered system induced a prolonged decrease in blood glucose levels among diabetic rats. The relative bioavailability of INS compared with subcutaneous injection in diabetic rats was found to be approximately 12%. These results suggested that the encapsulated INS-PLGA-lipid-PEG NPs are promising and should be investigated further in the near future as an effective INS oral delivery system.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Insulina/administração & dosagem , Nanopartículas/administração & dosagem , Polietilenoglicóis/administração & dosagem , Poliglactina 910/administração & dosagem , Administração Oral , Animais , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Células CACO-2 , Cápsulas , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacocinética , Humanos , Insulina/farmacocinética , Lipídeos , Masculino , Nanopartículas/metabolismo , Polietilenoglicóis/farmacocinética , Poliglactina 910/farmacocinética , Ratos , Ratos Wistar , Suínos , Comprimidos com Revestimento Entérico
12.
Chin Med J (Engl) ; 126(10): 1890-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23673105

RESUMO

BACKGROUND: Chronic kidney disease (CDK) is a worldwide health problem, but there is currently no effective treatment that can completely cure this disease. Recently, studies with mesenchymal stem cells (MSCs) on treating various renal diseases have shown breakthroughs. This study is to observe the homing features of MSCs transplanted via kidney artery and effects on renal fibrosis in a reversible unilateral ureteral obstruction (R-UUO) model. METHODS: Thirty-six Balb/c mice were divided into UUO group, UUO-MSC group, and sham group randomly, with 12 mice in each group. The MSCs had been infected by a lentiviral vector to express stably the luciferase reporter gene and green fluorescence protein genes (Luc-GFP-MSC). Homing of MSCs was tracked using in vivo imaging system (IVIS) 1, 3, 14, and 28 days after transplantation. Imaging results were verified by detecting GFP expression in frozen section under a fluorescence microscope. E-cadherin, α-SMA, TGF-ß1, and TNF-α mRNA expression in all groups at 1 and 4 weeks after transplantation were analyzed by quantitative PCR. RESULTS: Transplanted Luc-GFP-MSCs showed increased Luciferase expression 3 days after transplantation. The expression decreased from 7 days, weakened thereafter and could not be detected 14 days after transplantation. Quantitative PCR results showed that all gene expressions in UUO group and UUO-MSC group at 1 week had no statistical difference, while at 4 weeks, except TGF-ß expression (P > 0.05), the expression of E-cadherin, α-SMA, and TNF-α in the above two groups have statistical difference (P < 0.01). CONCLUSION: IVIS enables fast, noninvasive, and intuitive tracking of MSC homing in vivo. MSCs can be taken home to kidney tissues of the diseased side in R-UUO model, and renal interstitial fibrosis can be improved as well.


Assuntos
Fibrose/patologia , Nefropatias/patologia , Transplante de Células-Tronco Mesenquimais/métodos , Obstrução Ureteral/terapia , Animais , Células Cultivadas , Fibrose/terapia , Nefropatias/terapia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase em Tempo Real
13.
Yao Xue Xue Bao ; 48(2): 286-90, 2013 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-23672028

RESUMO

In this study, we explored the rationality of processing methods and mechanism of Aconiti Lateralis Radix (Fuzi) through comparing the chemical contents of diester alkaloids (DAs) and monoester alkaloids (MAs) in the raw material of Fuzi and its processed products. The results showed that the toxicity potency of MAs is at least lower than 1/64 to 1/180 of the toxicity potency of DAs. The contents of DAs in processed Fuzi decreased to 1/76.5 to 1/38.3 of the value of raw Fuzi. The contents of MAs in processed Fuzi significantly increased by 4.6 to 5.2 fold or basically the same as that of the raw Fuzi. The values of MAs/DAs of processed Fuzi were enhanced by 30 to 390 fold of the raw Fuzi. It was found that the contents of DAs were insignificantly different between "Wu dan fu pian" (steaming or stir-frying without Danba) and "Dan fu pian" (steaming or stir-frying with Danba). The result suggested that the abilities of "eliminating toxicity" of different processing methods were equivalent at all. In contrast, the contents of MAs contained in "Wu dan fu pian" were of 5.3 to 8.7 fold higher than the values in "Dan fu pian". This result suggested the processing method by steaming or stir-frying without Danba might have better effect for "conserving property" than the method processed with Danba stipulated by China Pharmacopoeia. We believe that the new processing method without Danba can be recommended in further application due to it offers a simple procedure and it will not introduce inorganic impurities in the products.


Assuntos
Aconitina/análise , Aconitum/química , Medicamentos de Ervas Chinesas/análise , Tecnologia Farmacêutica/métodos , Aconitina/análogos & derivados , Aconitina/toxicidade , Animais , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Medicamentos de Ervas Chinesas/toxicidade , Masculino , Ratos , Ratos Sprague-Dawley
14.
Nanoscale Res Lett ; 8(1): 4, 2013 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-23279853

RESUMO

A near-infrared (NIR)-responsive Aurod@pNIPAAm-PEGMA nanogel was synthesized in two steps, growing a PEGMA monolayer on the surface of gold nanorods (AuNRs), followed by in situ polymerization and cross-linking of N-iso-propylacrylamide (NIPAAm) and poly-(ethylene glycol)-methacrylate (PEGMA). The AuNRs and Aurod@pNIPAAm-PEGMA nanogel were characterized by UV-vis spectroscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy, respectively. The lower critical solution temperature of the Aurod@pNIPAAm-PEGMA nanogel could be tuned by changing the molar ratio of NIPAAm/PEGMA. The NIR-mediated drug release behavior of the Aurod@pNIPAAm-PEGMA nanogel was studied with zinc phthalocyanines (ZnPc4) as a drug model. It was also demonstrated that the loaded ZnPc4 could keep the capability of generating singlet oxygen, and the in vitro study showed a great photodynamic therapy (PDT) effect on Hela cells. It thus indicated the potential of this Aurod@pNIPAAm-PEGMA nanogel for application as a drug carrier in PDT, which might make contributions to oncotherapy.

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(10): 2795-802, 2013 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-24409739

RESUMO

In the present study, the authors put forward a parameterization method of correcting fine-mode Angstrom index with aerosol optical depth and volume distribution of aerosol derived from AERONET in Beijing over 2011. The parameterization method is coupled with aerosol optical depth spectral deconvolution algorithm to improve the accuracy of accumulation-mode fraction. The errors of estimated AMF are derived from underestimate of fine-mode Angstrom index errors. We calculate and simulate the extreme values of fine-mode Angstrom index, getting constraint conditions, and then establish the extreme values correction method. Results from sensitivity test suggest that extreme values of fine-mode Angstrom index are constrained in the reasonable range. Finemode Angstrom index and AMF are sensitive to normalized volume distribution of aerosol, ranging from 0.662 to 2.849 and from 0.08 to 0.84 due to different distribution. Mean deviation of accumulation-mode fraction is reduced from 0.072 to 0.044, and the difference is 38.89%, especially in winter and summer. Improving computational accuracy of accumulation-mode fraction can enhance that of anthropogenic aerosol optical thickness, and it has important significance of anthropogenic aerosol direct radiation force estimation and environmental quality assessment.

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(6): 1644-9, 2012 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22870657

RESUMO

Mineral dust is an important chemical component of aerosol, which has a significant impact on the climate and environmental changes. The spectral behavior of aerosol refractive indices at four wavelengths from 440 to 1 020 nm was analyzed based on one year observation obtained from Beijing AERONET site. The real parts of refractive index (n) in each band did not differ greatly, however the imaginary parts (k) showed a significant difference due to the absorption of mineral dust in aerosol. From 440 to 670 nm k decreased rapidly, while from 670 to 1 020 nm featured a lower, constant value. Accordingly, k(440 nm) could be considered separately with other three bands. Hence, we added mineral dust into the currently used three-component aerosol chemical model to form a new four-component model (i. e. BC, AS, dust and water) which is more suitable to represent the aerosol chemical composition. Then we presented a method to retrieve dust content in aerosols using this four-component model and refractive indices obtained from the sunphotometer measurements. Finally the dust content in aerosol was investigated under different weather conditions, i. e. clear, haze and dust in Beijing. The results showed that volume fractions of the dust component were 88%, 37% and 48% for clear, hazy and dusty day respectively, which was consistent with the coarse mode proportion in aerosols calculated from aerosol size distributions.

17.
Dongwuxue Yanjiu ; 33(3): 241-8, 2012 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22653850

RESUMO

Copulation patterns are important to understanding male mating strategies and stabilization strategies of social organizations in primates. However, information on copulation patterns of Asian primates is relatively rare. This study was undertaken to collect data on mating behavior and birth seasonality of Black-and-white Snub-nosed monkeys (Rhinopithecus bieti) using all occurrence sampling and Focal animal-scan sampling methods at Mt. Lasha, between January and December, 2011. Our study focused on observing mating frequency and birth rates. Snub-nosed monkeys mate year round, with two observable peaks: one reproductive peak during the mating season, roughly from August to October, and a second non-breeding peak during the birth season. It is unclear what biological significance this non-reproductive mating peak has. During our observation, we noted a lower ratio of mount to ejaculation and rare ejaculatory copulations, which indicated that every mating would not result in ejaculation. This study corroborates the previous view that the Rhinopithecus bieti's copulatory pattern is likely multiple-mount ejaculation (MME) or at the upper part of mating continuum of single-mount ejaculation (SME) toward MME. More ejaculatory copulations initiated by males than females indicate that MME is not only a mating strategy of males, but that males can influence the position of their copulatory pattern on the continuum between SME and MME. The mating frequencies significantly correlated with the birth rates with a delay of 6 to 7 months. Monkeys gave birth within a strict seasonality with a birth peak of March, which confirms the previous view. Infants were born with a certain degree of synchronization, but different populations displayed different modes of synchronizations.


Assuntos
Coeficiente de Natalidade , Colobinae/fisiologia , Comportamento Sexual Animal , Animais , China , Feminino , Masculino , Estações do Ano
18.
J Proteomics ; 75(13): 3977-86, 2012 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-22583932

RESUMO

Esophageal squamous cell carcinoma (ESCC) is one of the most common primary malignant tumor of digestive tract. However, the early diagnosis and molecular mechanisms that underlie tumor formation and progression have been progressed less. To identify new biomarkers for ESCC, we performed a comparative proteomic research. Isobaric tags for relative and absolute quantitation-based proteomic method was used to screen biomarkers between ESCC and normal. 802 non-redundant proteins were identified, 39 of which were differentially expressed with 1.5-fold difference (29 up-regulated and 10 down-regulated). Through Swiss-Prot and GO database, the location and function of differential proteins were analyzed, which are related to the biological processes of binding, cell structure, signal transduction, cell adhesion, etc. Among the differentially expressed proteins, TP-alpha, collagen alpha-1(VI) chain and S100A9 were verified to be upregulated in 77.19%, 75.44% and 59.65% of ESCC by immunohistochemistry and western-blot. Diagnostic value of these three proteins was validated. These results provide new insights into ESCC biology and potential diagnostic and therapeutic biomarkers, which suggest that TP-alpha, collagen alpha-1(VI) chain and S100A9 are potential biomarkers of ESCC, and may play an important role in tumorigenesis and development of ESCC.


Assuntos
Calgranulina B/sangue , Carcinoma de Células Escamosas/metabolismo , Colágeno Tipo VI/sangue , Neoplasias Esofágicas/metabolismo , Complexos Multienzimáticos/sangue , Proteômica/métodos , Adulto , Biomarcadores Tumorais/metabolismo , Western Blotting , Calgranulina B/biossíntese , Criança , Pré-Escolar , Colágeno Tipo VI/biossíntese , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Proteína Mitocondrial Trifuncional , Complexos Multienzimáticos/biossíntese , Sensibilidade e Especificidade , Regulação para Cima
19.
Can J Gastroenterol ; 26(1): 41-7, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22288069

RESUMO

OBJECTIVE: To identify and validate potential biomarkers of colorectal adenocarcinoma using a proteomic approach. METHODS: Multidimensional liquid chromatography/mass spectrometry was used to analyze biological samples labelled with isobaric mass tags for relative and absolute quantitation to identify differentially expressed proteins in human colorectal adenocarcinoma and paired normal mucosa for the discovery of cancerous biomarkers. Cancerous and noncancerous samples were compared using online and offline separation. Protein identification was performed using mass spectrometry. The downregulation of gelsolin protein in colorectal adenocarcinoma samples was confirmed by Western blot analysis and validated using immunohistochemistry. RESULTS: A total of 802 nonredundant proteins were identified in colorectal adenocarcinoma samples, 82 of which fell outside the expression range of 0.8 to 1.2, and were considered to be potential cancer-specific proteins. Immunohistochemistry revealed a complete absence of gelsolin expression in 86.89% of samples and a reduction of expression in 13.11% of samples, yielding a sensitivity of 86.89% and a specificity of 100% for distinguishing colorectal adenocarcinoma from normal tissue. CONCLUSIONS: These findings suggest that decreased expression of gelsolin is a potential biomarker of colorectal adenocarcinoma.


Assuntos
Adenocarcinoma/metabolismo , Biomarcadores Tumorais/biossíntese , Cromatografia Líquida/métodos , Neoplasias Colorretais/metabolismo , Gelsolina/biossíntese , Espectrometria de Massas em Tandem/métodos , Adenocarcinoma/genética , Adenocarcinoma/patologia , Idoso , Grupo com Ancestrais do Continente Asiático/genética , Western Blotting , China , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Regulação para Baixo/fisiologia , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Indicadores e Reagentes , Masculino , Pessoa de Meia-Idade , Proteômica/métodos , Neoplasias Retais/genética , Neoplasias Retais/metabolismo , Neoplasias Retais/patologia
20.
Zhonghua Yan Ke Za Zhi ; 48(10): 878-82, 2012 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-23302240

RESUMO

OBJECTIVE: To evaluate the characteristics of choroidal thickness changes and abnormalities in choroidal circulation in cases of central serous chorioretinopathy (CSC). METHODS: This was a case control study, we measured the bilateral choroidal thickness in 21 patients with unilateral CSC and 24 eyes of 24 age- and sex-matched normal subjects using enhanced depth imaging optical coherence tomography (EDI-OCT). The choroid was measured from the posterior edge of the retinal pigment epithelium (RPE) to the choroid-scleral junction at 500 µm intervals of a horizontal section from 3 mm temporal to the fovea to 3 mm nasal to the fovea. Paired-samples t-test was conducted to compare mean choroidal thicknesses between symptomatic eyes and fellow eyes of patients. The datum between patients and normal subjects were analyzed by independent-samples t-test. Fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were performed and the digital images were analyzed in CSC patients. RESULTS: The 21 CSC patients had a mean age of 45.6 years, and 12 patients (57.1%) were male. The choroid in symptomatic eyes was thickest beneath the fovea (519.0 ± 102.5) µm. It was significantly thicker than that in the fellow eyes (439.3 ± 94.1) µm (t = 4.171, P < 0.05). Choroidal thickness in both groups was significantly greater than that in the eyes of age- and sex-matched normal subjects (332.0 ± 67.3) µm (t = 7.125, 4.441; P < 0.05). Choroidal thickness at each of the other 12 points showed a similar tendency (t = 2.544 to 3.819, 4.799 to 7.816, 2.487 to 5.236; P < 0.05). ICGA showed a choroidal filling delay (100%), vessels dilation (90.5%), and focal choroidal hyperfluorescence (100%) surrounding leakage from the RPE in symptomatic eyes. Pigment epithelium detachment with abnormal choroidal circulation was observed in 6 fellow eyes. In 4 symptomatic eyes and 11 fellow eyes, ICGA revealed choroidal hyperfluorescence but FFA showed normal appearance. CONCLUSIONS: CSC seems to be a bilateral eye disease with choroidal focal ischemia followed by vessels congestion and hyperpermeability. EDI OCT is a useful tool for monitoring choroidal thickness changes caused by choroidal vascular hyperpermeability.


Assuntos
Coriorretinopatia Serosa Central/diagnóstico por imagem , Corioide/patologia , Adulto , Idoso , Estudos de Casos e Controles , Coriorretinopatia Serosa Central/patologia , Corioide/diagnóstico por imagem , Feminino , Angiofluoresceinografia/métodos , Humanos , Verde de Indocianina , Masculino , Pessoa de Meia-Idade , Radiografia , Tomografia de Coerência Óptica
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