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1.
Opt Express ; 29(15): 24338-24348, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34614681

RESUMO

An improved method of remote optical absorption spectroscopy and hyperspectral optical absorption imaging is described which takes advantage of the photoacoustic remote sensing detection architecture. A wide collection of photoacoustic excitation wavelengths ranging from 210 nm to 1550 nm was provided by a nanosecond tunable source allowing access to various salient endogenous chromophores such as DNA, hemeproteins, and lipids. Sensitivity of the device was demonstrated by characterizing the infrared absorption spectrum of water. Meanwhile, the efficacy of the technique was explored by recovering cell nuclei and oxygen saturation from a live chicken embryo model and by recovering adipocytes from freshly resected murine adipose tissue. This represents a continued investigation into the characteristics of the hyperspectral photoacoustic remote sensing technique which may represent an effective means of non-destructive endogenous contrast characterization and visualization.


Assuntos
Membrana Corioalantoide/química , DNA/análise , Hemoglobinas/análise , Lipídeos/análise , Microscopia/métodos , Técnicas Fotoacústicas/instrumentação , Tecnologia de Sensoriamento Remoto/instrumentação , Animais , Embrião de Galinha , Luz , Saturação de Oxigênio , Análise Espectral
2.
Biomed Res Int ; 2021: 6654683, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33997037

RESUMO

Chick (CE) or duck embryo eggs are known for nutritional supplement foods in traditional East countries for physical fitness enhancement and postpartum conditioning for many years. In this study, we evaluated the effects of different parts of the 10-day CE (embryo: CEr, yolk: CEw, and chorioallantoic membrane: CEp) on the antifatigue and antiaging activities in a D-galactose- (D-gal) induced aging mice model. The results showed CEp obviously increased the muscle weight and the liver and muscle glycogen content and enhanced exercise performance. In the antiaging assay, CEp significantly increased the activity of superoxide dismutase (SOD) and Glutathione Peroxidase (GPx). Moreover, the immunohistochemistry results of NRF-2 and HO-1 were also detected in the livers of mice in the D-gal/CEp group. The only partially potential such as CEr might improve OFT function with TG level, and CEw had strange grip strength. Therefore, we suggest that CEp has a potent antifatigue ability and could minimize the occurrence of age-associated disorders, more than other parts of the 10 days chicken embryo egg.


Assuntos
Envelhecimento/efeitos dos fármacos , Produtos Biológicos/farmacologia , Embrião de Galinha , Suplementos Nutricionais , Animais , Membrana Corioalantoide/química , Gema de Ovo/química , Galactose/efeitos adversos , Força da Mão , Fígado/química , Fígado/efeitos dos fármacos , Masculino , Medicina Tradicional Chinesa , Camundongos , Camundongos Endogâmicos C57BL , Força Muscular/efeitos dos fármacos , Músculos/efeitos dos fármacos , Músculos/metabolismo , Superóxido Dismutase/metabolismo
3.
Food Chem Toxicol ; 153: 112229, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33887397

RESUMO

The hen's egg test on chorioallantoic membrane (HET-CAM) is one of the most frequently used alternative tests for prediction of ocular irritation of cosmetic products. There are different HET-CAM protocols widely accepted, but there is no information about which of the protocols better correlates with the results obtained in product use clinical study under the conditions of use. Two Fix Time Methods (FTM) -Lüepke and the ICCVAM guideline - and two Reaction Time Methods (RTM) -ECVAM DBALM Prot. No. 47 and No. 96- were employed to test 18 cosmetic products. Simultaneously, they were evaluated by an ophthalmological clinical test. A unified classification system was used, and products were classified into four irritation levels: non-irritant, weak, moderate and severe irritant. The duration of use (rinse-off or leave-on), and the concentration and type of surfactants were taken into account in the analysis. All the products that were classified as non-irritant by any HET-CAM protocols were also safe in the product use clinical study. The product that was found to be non-safe in the product use clinical evaluation was also unsuitable by most of the HET-CAM protocols. These results were employed to develop an algorithm that allows selecting the appropriate HET-CAM protocol for each type of product to be tested.


Assuntos
Alternativas aos Testes com Animais , Membrana Corioalantoide/química , Cosméticos/toxicidade , Oftalmopatias/induzido quimicamente , Tensoativos/toxicidade , Animais , Embrião de Galinha , Humanos , Irritantes/toxicidade , Tensoativos/química
4.
J Vis Exp ; (168)2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33645558

RESUMO

The chicken embryo and the blood-vessel rich chorioallantoic membrane (CAM) is a valuable in vivo model to investigate biomedical processes, new ultrasound pulsing schemes, or novel transducers for contrast-enhanced ultrasound imaging and microbubble-mediated drug delivery. The reasons for this are the accessibility of the embryo and vessel network of the CAM as well as the low costs of the model. An important step to get access to the embryo and CAM vessels is to take the egg content out of the eggshell. In this protocol, three methods for taking the content out of the eggshell between day 5 and 8 of incubation are described thus allowing the embryos to develop inside the eggshell up to these days. The described methods only require simple tools and equipment and yield a higher survival success rate of 90% for 5-day, 75% for 6-day, 50% for 7-day, and 60% for 8-day old incubated eggs in comparison to ex ovo cultured embryos (~50%). The protocol also describes how to inject cavitation nuclei, such as microbubbles, into the CAM vascular system, how to separate the membrane containing the embryo and CAM from the rest of the egg content for optically transparent studies, and how to use the chicken embryo and CAM in a variety of short-term ultrasound experiments. The in vivo chicken embryo and CAM model is extremely relevant to investigate novel imaging protocols, ultrasound contrast agents, and ultrasound pulsing schemes for contrast-enhanced ultrasound imaging, and to unravel the mechanisms of ultrasound-mediated drug delivery.


Assuntos
Membrana Corioalantoide/química , Meios de Contraste , Sistemas de Liberação de Medicamentos , Endotélio Vascular/diagnóstico por imagem , Microbolhas , Propídio/administração & dosagem , Ultrassonografia/métodos , Animais , Embrião de Galinha , Galinhas , Corantes/administração & dosagem , Casca de Ovo/química , Endotélio Vascular/efeitos dos fármacos
5.
Int J Biol Macromol ; 160: 296-306, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32439438

RESUMO

This research paper demonstrates efficacy of chitosan and thyroxine loaded chitosan (CS) dressings for their angiogenic and wound healing potential. The dressings were prepared by freeze gelation method. Thyroxine was loaded by physical adsorption into chitosan membranes. The porosity was analyzed by scanning electron microscopy (SEM) and chemical structures were investigated by Fourier transform infra-red spectroscopy (FTIR). Cell culture studies showed materials were non-toxic and chorioallantoic membranes assay (CAM) confirmed that the thyroxine loaded chitosan stimulated angiogenesis much higher than simple chitosan dressings. In addition, thyroxine loaded dressings showed excellent wound healing potential when tested on full thickness rats wounds. A good epithelialization was obtained along with robust wound closure. Overall, as compared to chitosan, thyroxine containing membranes showed high level of angiogenesis and fast wound healing.


Assuntos
Quitosana/química , Neovascularização Fisiológica/efeitos dos fármacos , Tiroxina/química , Tiroxina/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Bandagens , Células Cultivadas , Membrana Corioalantoide/química , Porosidade , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
6.
Clin Hemorheol Microcirc ; 70(4): 487-494, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30400081

RESUMO

INTRODUCTION: The oral squamous cell carcinoma (OSCC) is a leading cause of death in human malignancies. The aim of this study is to integrate the CAM Assay as a reliable and good working in vivo model for the evaluation of OSCC tumor samples and its growth into the clinical work flow. MATERIAL AND METHODS: Fresh human Tumor samples (OSCCs) 1×1 cm in size were cut into 350-450µm thick slices by a Vibratome and put on the prepared CAM model.After growth of the tumor tissue on the CAM, we started with topical induction of proinflammatory cytokines (TNFα) and growth factors (TGFß). After further growth of the tumor on the assay, we explanted the tumor tissue and first performed microscopic and then immunohistochemical examinations. E-cadherin and vimentin were used as Epithelial-to-mesenchymal transition (EMT) -makers and the histologic preparations were evaluated histomorphometrically. The results were correlated with clinical parameters of the patients. RESULTS: Under TNFα, the small tumors (T1 / T2) show higher E-cadherin expression than larger tumors (T3 / T4). The vimentin expression under TNFα behaved in the opposite direction, at T1 / T2 the expression decreased in T3 / T4 increased. Furthermore, an increased E-cadherin expression in N0 and diminished E-cadherin expression in N1 / N2b patients could be detected depending on the N-stage of the patients. Vimentin, on the other hand, was reduced in the N0 group and expressed more frequently in the N1 / N2b group. TGFß induction also led to increased expression of vimentin in the T3 / T4 tumors and N1 / N2b stages. CONCLUSION: By integrating a CAM assay into the clinical workflow, tumors with preserved tumor architecture can be cultured and subjected to histological and molecular biology studies. Effects on biological behavior are recognizable and demonstrable in this model. The key markers E-cadherin and vimentin alone are not sufficient to represent the complexity of the EMT in this model. Further molecular biology and signaling pathway analyzes are necessary.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Membrana Corioalantoide/química , Neoplasias Bucais/diagnóstico , Adulto , Idoso , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/mortalidade , Neoplasias Bucais/patologia , Taxa de Sobrevida , Fluxo de Trabalho
7.
PLoS One ; 12(8): e0182301, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28763512

RESUMO

Angiogenesis, the sprouting of new blood vessels from existing vasculature, involves multiple complex biological processes, and it is an essential step for hemostasis, tissue healing and regeneration. Angiogenesis stimulants can ameliorate human disease conditions including limb ischemia, chronic wounds, heart disease, and stroke. The current strategies to improve the bioavailability of pro-angiogenic growth factors, including VEGF and FGF2, have remained largely unsuccessful. This study demonstrates that small molecules, termed click-xylosides, can promote angiogenesis in the in vitro matrigel tube formation assay and the ex ovo chick chorioallantoic membrane assay, depending on their aglycone moieties. Xyloside treatment enhances network connectivity and cell survivability, thereby, maintaining the network structures on matrigel culture for an extended period of time. These effects were achieved via the secreted xyloside-primed glycosaminoglycans (GAG) chains that in part, act through an ERK1/2 mediated signaling pathway. Through the remodeling of GAGs in the extracellular matrix of endothelial cells, the glycan approach, involving xylosides, offers great potential to effectively promote therapeutic angiogenesis.


Assuntos
Glicosídeos/química , Neovascularização Fisiológica , Polissacarídeos/química , Indutores da Angiogênese/uso terapêutico , Animais , Proliferação de Células , Sobrevivência Celular , Embrião de Galinha , Membrana Corioalantoide/química , Feminino , Glicosaminoglicanos/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Regeneração
8.
Ecotoxicol Environ Saf ; 140: 156-161, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28258041

RESUMO

BACKGROUND: Particulate matter (PM) is the most efficient vehicle for the inhalation and absorption of toxic substances into the body. METHOD: The present study was aimed at testing the hypothesis that PM10 samples collected on quartz filters exert an angiogenic activity in vivo in the chick embryo chorioallantoic membrane (CAM) assay. RESULTS: When the low, medium, and high PM10 concentrations filters were tested in the CAM assay, an increasing number of microvessels was detectable after 4 days of applications of the filters. Moreover, at histological level, numerous microvessels and a dense inflammatory infiltrate were recognizable in the CAM mesenchyme. CONCLUSION: Our data show a clear dose-response relationship between the dose variable (PM10 and Bap) and the outcome variable. So far, the PM10 target value is determined on the basis of regulatory agreements and is not health-based. In addition, the mere gravimetric measure of PM10 cannot be considered a fully reliable surrogate of the overall toxicity of the mixture.


Assuntos
Poluentes Atmosféricos/toxicidade , Membrana Corioalantoide/irrigação sanguínea , Neovascularização Patológica/induzido quimicamente , Material Particulado/toxicidade , Poluentes Atmosféricos/análise , Animais , Carcinógenos/análise , Carcinógenos/toxicidade , Embrião de Galinha , Membrana Corioalantoide/química , Metais/análise , Metais/toxicidade , Microvasos/fisiologia , Nitrocompostos/análise , Nitrocompostos/toxicidade , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade
9.
J Biophotonics ; 10(5): 708-717, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27588712

RESUMO

Dysfunctions in tissue metabolism can be detected at early stages by oxygen partial pressure (pO2 ) measurement. The measurement of emission lifetimes offers very promising and non-invasive approach to estimate pO2 in vivo. This study compares two extensively used oxygen sensors and assesses their in vivo oxygen sensitivity and phototoxic effect. Luminescence lifetime of Ru-polypyridyl complex and of Pd-porphyrin is measured in the Chick's Chorioallantoic Membrane (CAM) model with a dedicated optical fiber-based, time-resolved spectrometer. The Pd-porphyrin luminescence lifetimes measured in the CAM model exposed to different pO2 levels are longer and have a broader dynamic range (10-100 µs) than those of Ru-polypyridyl complex (0.6-1 µs). The combined statistical analysis based on an estimate of the kurtosis and skewness, bootstrapping method and routine normality tests is performed. The indicators of the averages and signal to noise ratio stability are also calculated. The combination of several data processing allows selection of the better sensor for a given application. In particular, it is found that the advantage of Ru-polypyridyl complex over Pd-porphyrin is two-fold: i) Ru-polypyridyl complex datasets have consistently better statistical characteristics, ii) Ru-polypyridyl exhibits lower cytotoxicity.


Assuntos
Membrana Corioalantoide/química , Mesoporfirinas/química , Metaloporfirinas/química , Compostos Organometálicos/química , Oxigênio/análise , Fenantrolinas/química , Animais , Embrião de Galinha , Luminescência , Pressão Parcial , Análise Espectral
10.
Sci Rep ; 6: 35347, 2016 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-27734947

RESUMO

Peptide analogues derived from bioactive hormones such as somatostatin or certain growth factors have great potential as angiogenesis inhibitors for cancer applications. In an attempt to combat emerging drug resistance many FDA-approved anti-angiogenesis therapies are co-administered with cytotoxic drugs as a combination therapy to target multiple signaling pathways of cancers. However, cancer therapies often encounter limiting factors such as high toxicities and side effects. Here, we combined two anti-angiogenic epitopes that act on different pathways of angiogenesis into a single non-toxic cyclic peptide framework, namely MCoTI-II (Momordica cochinchinensis trypsin inhibitor-II), and subsequently assessed the anti-angiogenic activity of the novel compound. We hypothesized that the combination of these two epitopes would elicit a synergistic effect by targeting different angiogenesis pathways and result in improved potency, compared to that of a single epitope. This novel approach has resulted in the development of a potent, non-toxic, stable and cyclic analogue with nanomolar potency inhibition in in vitro endothelial cell migration and in vivo chorioallantoic membrane angiogenesis assays. This is the first report to use the MCoTI-II framework to develop a 2-in-1 anti-angiogenic peptide, which has the potential to be used as a form of combination therapy for targeting a wide range of cancers.


Assuntos
Inibidores da Angiogênese/química , Ciclotídeos/química , Epitopos/química , Momordica/química , Neoplasias/tratamento farmacológico , Peptídeos Cíclicos/farmacologia , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Membrana Corioalantoide/química , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Eritrócitos/citologia , Hemólise , Células Endoteliais da Veia Umbilical Humana , Humanos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Meliteno/química , Neovascularização Patológica , Codorniz , Transdução de Sinais/efeitos dos fármacos , Tripsina/química
11.
Anal Sci ; 32(10): 1077-1082, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27725607

RESUMO

In this paper, an egg-shell membrane has been used for efficient immobilization and stabilization of glucose oxidase. This membrane was used for developing a simple and reusable method for estimation of glucose in biological samples. The proposed sensor was effectively used in a wide glucose concentration range (1 - 1000 mM) with fast response time of 70 s for higher concentrations and 120 s for lower concentrations. The results of response study for the fabricated sensor show limit of detection of 4.761 mM with high sensitivity over the entire concentration range (1 - 1000 mM). Most interestingly, the membrane used in the fabricated sensor could be repeatedly used for glucose analysis 150 times and it exhibited a shelf-life of more than 6 weeks. The proposed sensor was also demonstrated for estimation of glucose in human blood samples.


Assuntos
Técnicas Biossensoriais/métodos , Membrana Corioalantoide/química , Casca de Ovo , Enzimas Imobilizadas/química , Glucose Oxidase/química , Glucose/análise , Animais , Técnicas Biossensoriais/instrumentação , Calibragem , Desenho de Equipamento , Software , Fatores de Tempo
12.
J Proteomics ; 130: 11-25, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26344478

RESUMO

The avian eggshell membrane (ESM) is a meshwork made up of highly cross-linked protein fibers and it is a scaffold upon which biomineralization of the eggshell is initiated. The ESM and associated shell participates in embryonic development by providing physical and chemical protection against pathogen invasion. We performed quantitative proteomic analysis of ESM proteins on multiple days during the three phases of embryonic development. The ESMs were stripped from both fertilized and unfertilized eggs at different days of incubation, and solubilized in a novel manner using TCEP-HCl (Tris (2-carboxyethyl) phosphine hydrochloride). The changes in ESM proteins between occurred during incubation were analyzed. Bioinformatics analysis revealed that of the 12 functional protein clusters identified, protease inhibitors were present at all phases of chick development. A group of proteins involved in calcium binding and oxygen transport were only present during the second phase. Extracellular matrix, cell adhesion proteins related to the vascularization of chorioallantoic membrane (CAM), antimicrobial proteins and proteins involved in the binding and transport of lipids were found in the second and third phases of development. These findings provide insight into the functionality and evolving nature of ESM associated proteins involved in chick embryonic development. BIOLOGICAL SIGNIFICANCE: The eggshell membranes (ESMs) are a fibrous scaffold that consists of highly crosslinked collagens (types I, V but mainly X), glycoproteins and CREMPs (cysteine-rich eggshell membrane proteins). The ESMs aid in the development of the chick embryo and protect it against pathogen invasion. This biopolymeric fibrous net functions as a platform for nucleation of the calcitic eggshell which provides a primary physical barrier against bacterial ingress. Comparative proteomic analyses of proteins in the ESMs from fertilized eggs and unfertilized eggs showed changes in their levels which varied between the specific phases of chick embryogenesis across 19 days of incubation. Bioinformatics characterization of these ESM proteins provides understanding of their evolving nature during chick embryonic development.


Assuntos
Proteínas Aviárias/metabolismo , Proteínas do Ovo/metabolismo , Proteínas de Membrana/metabolismo , Proteoma , Animais , Embrião de Galinha , Galinhas , Membrana Corioalantoide/química , Desenvolvimento Embrionário , Lipídeos/química , Óvulo/metabolismo , Fosfinas/química , Proteômica/métodos , Zigoto/metabolismo
13.
J Tissue Eng Regen Med ; 10(6): 496-506, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-23712963

RESUMO

Neovascularization of adipose tissue equivalents is a crucial step in successful adipose tissue engineering, since insufficient vascularization results in graft resorption in an in vivo situation. A possible cellular approach to overcome this limitation is the co-implantation of adipose-derived stem cells (ASCs) with endothelial cells to stimulate the formation of a vascular network. We investigated the potential of ASCs derived from human abdominal fat tissue co-cultured with endothelial progenitor cells (EPCs) from human peripheral blood to stimulate neovascularization of fibrin constructs on the chorioallantoic membrane (CAM) of fertilized chicken eggs, in direct comparison to human umbilical vein endothelial cells (HUVECs). After 9 days of incubation, cell-fibrin constructs were explanted and histologically evaluated with respect to ingrowth of avian blood vessels into the construct and formation of human blood vessels by co-implanted endothelial cells. When administered on the CAM, ASCs successfully guided host vasculature into the construct (angiogenesis) and guided formation of capillary-like structures by co-implanted human endothelial cells (vasculogenesis), with HUVECs being superior to EPCs, leading to a perfused avian and human capillary network within the fibrin construct. However, the results also showed that perfused human blood vessels were only observed near the CAM compared to unperfused capillary-like structures near the top of the construct, indicating that perfusion of the cell-fibrin construct takes longer than 9 days. In conclusion, as blood vessel formation is an essential step during adipogenic differentiation, the data support our hypothesis that cellular communication between transplanted ASCs and endothelial cells is beneficial for vasculogenesis. Copyright © 2013 John Wiley & Sons, Ltd.


Assuntos
Tecido Adiposo/metabolismo , Membrana Corioalantoide/química , Células Endoteliais/metabolismo , Fibrina/farmacologia , Modelos Biológicos , Neovascularização Fisiológica , Células-Tronco/metabolismo , Tecido Adiposo/citologia , Adulto , Animais , Embrião de Galinha , Técnicas de Cocultura , Células Endoteliais/citologia , Feminino , Humanos , Masculino , Células-Tronco/citologia
14.
Int J Nanomedicine ; 10: 609-31, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25670897

RESUMO

In this work, a peptide for ocular delivery (POD) and human immunodeficiency virus transactivator were conjugated with biodegradable poly(lactic-co-glycolic acid) (PGLA)-polyethylene glycol (PEG)-nanoparticles (NPs) in an attempt to improve ocular drug bioavailability. The NPs were prepared by the solvent displacement method following two different pathways. One involved preparation of PLGA NPs followed by PEG and peptide conjugation (PLGA-NPs-PEG-peptide); the other involved self-assembly of PLGA-PEG and the PLGA-PEG-peptide copolymer followed by NP formulation. The conjugation of the PEG and the peptide was confirmed by a colorimetric test and proton nuclear magnetic resonance spectroscopy. Flurbiprofen was used as an example of an anti-inflammatory drug. The physicochemical properties of the resulting NPs (morphology, in vitro release, cell viability, and ocular tolerance) were studied. In vivo anti-inflammatory efficacy was assessed in rabbit eyes after topical instillation of sodium arachidonate. Of the formulations developed, the PLGA-PEG-POD NPs were the smaller particles and exhibited greater entrapment efficiency and more sustained release. The positive charge on the surface of these NPs, due to the conjugation with the positively charged peptide, facilitated penetration into the corneal epithelium, resulting in more effective prevention of ocular inflammation. The in vitro toxicity of the NPs developed was very low; no ocular irritation in vitro (hen's egg test-chorioallantoic membrane assay) or in vivo (Draize test) was detected. Taken together, these data demonstrate that PLGA-PEG-POD NPs are promising vehicles for ocular drug delivery.


Assuntos
Anti-Inflamatórios/farmacologia , Peptídeos Penetradores de Células/farmacologia , Sistemas de Liberação de Medicamentos , Epitélio Corneano/efeitos dos fármacos , Glicolatos/química , Ácido Láctico/química , Nanopartículas/química , Ácido Poliglicólico/química , Animais , Proteínas Reguladoras de Apoptose/química , Fatores de Transcrição Hélice-Alça-Hélice Básicos/química , Sobrevivência Celular/efeitos dos fármacos , Galinhas , Membrana Corioalantoide/química , Portadores de Fármacos/química , Epitélio Corneano/citologia , Feminino , Células HeLa , Células Hep G2 , Humanos , Microscopia Confocal , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos , Proteínas Recombinantes de Fusão/química , Survivina , Produtos do Gene tat do Vírus da Imunodeficiência Humana/química
15.
J Biomed Opt ; 19(7): 77004, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25036215

RESUMO

Measuring tissue oxygenation in vivo is of interest in fundamental biological as well as medical applications. One minimally invasive approach to assess the oxygen partial pressure in tissue (pO2) is to measure the oxygen-dependent luminescence lifetime of molecular probes. The relation between tissue pO2 and the probes' luminescence lifetime is governed by the Stern-Volmer equation. Unfortunately, virtually all oxygen-sensitive probes based on this principle induce some degree of phototoxicity. For that reason, we studied the oxygen sensitivity and phototoxicity of dichlorotris(1, 10-phenanthroline)-ruthenium(II) hydrate [Ru(Phen)] using a dedicated optical fiber­based, time-resolved spectrometer in the chicken embryo chorioallantoic membrane. We demonstrated that, after intravenous injection, Ru(Phen)'s luminescence lifetime presents an easily detectable pO2 dependence at a low drug dose (1 mg∕kg) and low fluence (120 mJ∕cm2 at 470 nm). The phototoxic threshold was found to be at 10 J∕cm2 with the same wavelength and drug dose, i.e., about two orders of magnitude larger than the fluence necessary to perform a pO2 measurement. Finally, an illustrative application of this pO2 measurement approach in a hypoxic tumor environment is presented.


Assuntos
Corantes Fluorescentes/química , Imagem Óptica/métodos , Oxigênio/análise , Fenantrolinas/química , Rutênio/química , Animais , Linhagem Celular Tumoral , Embrião de Galinha , Membrana Corioalantoide/irrigação sanguínea , Membrana Corioalantoide/química , Membrana Corioalantoide/efeitos dos fármacos , Membrana Corioalantoide/metabolismo , Corantes Fluorescentes/farmacocinética , Corantes Fluorescentes/toxicidade , Humanos , Neoplasias Experimentais , Fibras Ópticas , Imagem Óptica/instrumentação , Compostos Organometálicos/química , Compostos Organometálicos/farmacocinética , Compostos Organometálicos/toxicidade , Pressão Parcial , Fenantrolinas/farmacocinética , Fenantrolinas/toxicidade , Rutênio/farmacocinética , Rutênio/toxicidade , Distribuição Tecidual
16.
Food Chem ; 141(3): 2117-21, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23870936

RESUMO

The eggshell membrane (ESM) is a naturally occurring biological polymer, which can be extracted from eggshells, and has been used for adsorption of dyes or heavy metals, as a semipermeable membrane to control particle transport, and as a natural biocompatible material for tissue replacement. In this study, we used hydrogen peroxide to control the pore size and fibre crossing density of the ESM. Structural and chemical properties were investigated using AFM, optical microscopy, contact angle, and FTIR. We show that the structure and permeability of the ESM can be controlled by timed exposure to H2O2 and we demonstrate this effect using red blood cells. This process provides a simple method for preparing biocompatible membranes, with controlled selectivity for biofiltration applications.


Assuntos
Materiais Biocompatíveis/química , Membrana Corioalantoide/química , Casca de Ovo/química , Peróxido de Hidrogênio/farmacologia , Alantoide , Animais , Galinhas , Membrana Corioalantoide/efeitos dos fármacos , Casca de Ovo/efeitos dos fármacos , Tamanho da Partícula , Porosidade
17.
Biomaterials ; 34(28): 6638-48, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23727263

RESUMO

Tissue engineering of autologous lung tissue aims to become a therapeutic alternative to transplantation. Efforts published so far in creating scaffolds have used harsh decellularization techniques that damage the extracellular matrix (ECM), deplete its components and take up to 5 weeks to perform. The aim of this study was to create a lung natural acellular scaffold using a method that will reduce the time of production and better preserve scaffold architecture and ECM components. Decellularization of rat lungs via the intratracheal route removed most of the nuclear material when compared to the other entry points. An intermittent inflation approach that mimics lung respiration yielded an acellular scaffold in a shorter time with an improved preservation of pulmonary micro-architecture. Electron microscopy demonstrated the maintenance of an intact alveolar network, with no evidence of collapse or tearing. Pulsatile dye injection via the vasculature indicated an intact capillary network in the scaffold. Morphometry analysis demonstrated a significant increase in alveolar fractional volume, with alveolar size analysis confirming that alveolar dimensions were maintained. Biomechanical testing of the scaffolds indicated an increase in resistance and elastance when compared to fresh lungs. Staining and quantification for ECM components showed a presence of collagen, elastin, GAG and laminin. The intratracheal intermittent decellularization methodology could be translated to sheep lungs, demonstrating a preservation of ECM components, alveolar and vascular architecture. Decellularization treatment and methodology preserves lung architecture and ECM whilst reducing the production time to 3 h. Cell seeding and in vivo experiments are necessary to proceed towards clinical translation.


Assuntos
Matriz Extracelular/química , Pulmão/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Embrião de Galinha , Membrana Corioalantoide/química , Membrana Corioalantoide/citologia , Pulmão/citologia , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Neovascularização Fisiológica/fisiologia , Ratos
18.
Br Poult Sci ; 54(1): 106-11, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23444860

RESUMO

1. The aim of this study was to evaluate the amount and quality of genomic DNA isolated from embryos and their chorioallantoic membranes (CAM) and to investigate the utility of different PCR methods for identifying the sex of Japanese quail embryos. 2. Fertilised eggs were incubated at 37°C for 120 h and DNA was isolated from samples of embryos and CAM. Target regions of the CHD-W gene or XhoI repeat sequence were amplified by PCR and examined on agarose gels or by using a capillary electrophoresis system. 3. DNA samples from embryos had significantly higher OD260 values than those from CAM, while OD260/280 values were not significantly different between embryos and CAM. 4. Gender identification was not possible by PCR amplification of the CHD gene region or XhoI repeat sequences examined on agarose gels, whereas males and females of Japanese quail were distinguishable when PCR products of the CHD gene were separated by capillary electrophoresis. 5. The results showed that high molecular weight DNA could be isolated from both embryo and CAM of Japanese quail. DNA isolated from CAM could be used for molecular genetic studies where embryos would be used for other purposes, such as in situ hybridisation. A capillary electrophoresis system could be used for identifying the gender of Japanese quail embryos.


Assuntos
Proteínas Aviárias/química , Coturnix/genética , Proteínas de Ligação a DNA/química , Análise para Determinação do Sexo/métodos , Animais , Membrana Corioalantoide/química , Membrana Corioalantoide/metabolismo , Coturnix/embriologia , Eletroforese Capilar , Embrião não Mamífero/química , Embrião não Mamífero/fisiologia , Feminino , Marcadores Genéticos , Masculino
19.
Carbohydr Polym ; 93(1): 279-84, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23465931

RESUMO

Curcumin, a lipophilic compound found in the plant Curcuma longa L., exhibits a wide range of pharmacological activity; however, its therapeutic use has been limited because of its low bioavailability following oral administration. The aim of this study was to evaluate the viscoelastic characteristics and biocompatibility of a curcumin/xanthan:galactomannan hydrogel (X:G) system after topical application on chick embryo chorioallantoic membrane (CAM), a system established with a view toward curcumin nasal or topical pharmaceutical applications or possible administration in cosmetics or foods. A rheological analysis indicated that incorporation of curcumin did not alter the viscoelastic characteristics of the X:G hydrogel, suggesting that there was no change in the structure of the gel network. X:G hydrogels did not induce CAM tissue injury and the curcumin/X:G hydrogel system was also highly biocompatible. We conclude that the X:G hydrogel represents a potential matrix for curcumin formulations.


Assuntos
Curcumina/química , Hidrogéis/química , Mananas/química , Teste de Materiais/métodos , Reologia/métodos , Administração Tópica , Animais , Materiais Biocompatíveis/química , Embrião de Galinha , Membrana Corioalantoide/química , Membrana Corioalantoide/efeitos dos fármacos , Curcumina/administração & dosagem , Galactanos/química , Galactose/análogos & derivados , Neovascularização Fisiológica/efeitos dos fármacos , Gomas Vegetais/química , Polissacarídeos Bacterianos/química , Substâncias Viscoelásticas/química
20.
Phytomedicine ; 19(3-4): 301-5, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22240079

RESUMO

Fissistigma cavaleriei (Levl) Rehd (Annonaceae) is used as a folklore medicine for treatment of inflammation, arthritis, and tuberculosis by Miao people in China. In the present study, the antiangiogenic activity of F. cavaleriei was investigated. The chorioallantoic membrane of the fertilized hen's egg (CAM assay) was used to determine antiangiogenic activity of the plant extract. Compound (1), a compound with antiangiogenic activity, was isolated by bioassay-guided fractionation from F. cavaleriei for the first time. The structure of compound (1) was elucidated on the basis of spectroscopic methods. Colorimetric COX (ovine) inhibitor screening assay was used to determine its inhibitory effect on COX-1 and COX-2. MTT and Sulforhodamine B assays were used to investigate its cytotoxic effects on tumor cell lines. As a result, compound (1) showed a selectively inhibiting effect on COX-2 and could inhibit the growth of tumor cells in vitro. The antitumor activity of compound (1) was further confirmed by the observation that compound (1) administration significantly inhibited the growth of S-180 cells in mice. Moreover, compound (1) was able to enhance the antitumor activity of doxorubicin in the mice bearing with S-180 cells while combined with doxorubicin. In conclusion, compound (1) is a multi-target molecule and further experimental investigations are needed to determine whether it can be used as a lead molecule for tumor treatment.


Assuntos
Alcaloides/isolamento & purificação , Inibidores da Angiogênese/farmacologia , Annonaceae/química , Antineoplásicos Fitogênicos/farmacologia , Bioensaio/métodos , Raízes de Plantas/química , Alcaloides/química , Alcaloides/farmacologia , Inibidores da Angiogênese/química , Inibidores da Angiogênese/isolamento & purificação , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Fracionamento Químico , Embrião de Galinha , Membrana Corioalantoide/química , Membrana Corioalantoide/efeitos dos fármacos , Ciclo-Oxigenase 1/metabolismo , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/farmacologia , Doxorrubicina/farmacologia , Sinergismo Farmacológico , Formazans/química , Humanos , Isoindóis/farmacologia , Células K562 , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Rodaminas/química , Sais de Tetrazólio/química , Ensaios Antitumorais Modelo de Xenoenxerto
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