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1.
Arq. bras. oftalmol ; 87(1): e2021, 2024. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1527812

RESUMO

ABSTRACT Purpose: The purpose of this study was to investigate the vascular effects of photobiomodulation using a light-emitting diode on the chorioallantoic embryonic membrane of chicken eggs grouped into different times of exposure and to detect the morphological changes induced by the light on the vascular network architecture using quantitative metrics. Methods: We used a phototherapy device with light-emitting diode (670 nm wavelength) as the source of photobiomodulation. We applied the red light at a distance of 2.5 cm to the surface of the chorioallantoic embryonic membrane of chicken eggs in 2, 4, or 8 sessions for 90 s and analyzed the vascular network architecture using AngioTool software (National Cancer Institute, USA). We treated the negative control group with 50 μl phosphate-buffered-saline (pH 7.4) and the positive control group (Beva) with 50 μl bevacizumab solution (Avastin, Produtos Roche Químicos e Farmacêuticos, S.A., Brazil). Results: We found a decrease in total vessel length in the Beva group (24.96% ± 12.85%) and in all the groups that received 670 nm red light therapy (2× group, 34.66% ± 8.66%; 4× group, 42.42% ± 5.26%; 8× group, 38.48% ± 6.96%), compared with the negative control group. The fluence of 5.4 J/cm2 in 4 sessions (4×) showed more regular vessels. The number of junctions in the groups that received a higher incidence of 670 nm red light (4× and 8×) significantly decreased (p<0.0001). Conclusion: Photo-biomodulation helps reduce vascularization in chorioallantoic embryonic membrane of chicken eggs and changes in the network architecture. Our results open the possibility of future clinical studies on using this therapy in patients with retinal diseases with neovascular components, especially age-related macular degeneration.


RESUMO Objetivo: investigar os efeitos vasculares da foto-biomodulação com diodo emissor de luz utilizando membrana embrionária corioalantóide de ovos de galinhas em grupos com diferentes tempos de exposição e detectar as alterações morfológicas por meio de métricas quantitativas promovidas pela luz na arquitetura da rede vascular. Métodos: Um aparelho de fototerapia com diodo emissor de luz no comprimento de onda de 670 nm foi usado como fonte de fotobiomodulação. A luz vermelha foi aplicada a uma distância de 2,5 cm da superfície da membrana embrionária corioalantóide em 2, 4 ou 8 sessões de 90 s a arquitetura da rede vascular foi analisada por meio do software AngioTool (National Cancer Institute, USA). Usamos um grupo controle negativo tratado com 50 µL de solução salina tamponada com fosfato (PBS) pH 7,4 e um grupo controle positivo (Beva) tratado com 50 µL de solução de bevacizumabe (Avastin, Produtos Roche Químicos e Farmacêuticos S.A., Brasil). Resultados: Uma diminuição no comprimento total do vaso foi detectada para o grupo Beva (24,96 ± 12,85%), e para todos os grupos que receberam terapia de luz vermelha de 670 nm, 34,66 ± 8,66% (2x), 42,42 ± 5,26% (4x) e 38,48 ± 6,96% (8x) em comparação ao grupo controle. A incidência de 5,4 J/cm2 em 4 sessões (4x) mostrou vasos mais regulares. A redução foi mais intensa nos grupos que receberam maior incidência de luz vermelha de 670 nm (4x e 8x). Conclusão: A fotobiomodulação contribui para a redução da vascularização nos vasos da membrana embrionária corioalantóide de ovos de galinhas e mudanças na arquitetura da rede. Os achados deste experimento abrem a possibilidade de considerar um estudo clínico usando esta terapia em pacientes com doenças retinais com componentes neovasculares, especialmente degeneração macular relacionada à idade.

2.
Indian J Ophthalmol ; 2023 Mar; 71(3): 977-982
Artigo | IMSEAR | ID: sea-224909

RESUMO

Purpose: To develop a viable in vivo chorioallantoic membrane (CAM) model to study the growth and invasion of patient?derived retinoblastoma (RB) and choroidal melanoma (CM) xenografts (PDXs). The study utilizes primary tumor samples instead of cancer cell lines, which provides a more authentic representation of tumors due to conserved morphology and heterogeneity. Methods: Fertilized chicken eggs were procured, windowed, and their CAM layers were dropped. On embryonic development day (EDD) 10, freshly cut patient?derived CM and RB tumors were implanted on the CAM layer and the setup was incubated for 7 days. The tumor?embedded CAM layer was harvested on EDD 17, and the extracted tumor samples were subjected to hematoxylin and eosin staining and immunohistochemical analysis to evaluate the extent of tumor invasion. Results: Significant changes in the vascularity around the RB and CM PDXs were observed, indicating an angiogenic environment. The cross?sectional histological view of the tumor implant site revealed the invasion of both the tumors into the CAM mesoderm. Invasion of CM into CAM mesoderm was visualized in the form of pigmented nodules, and that of RB was indicated by synaptophysin and Ki?67 positivity in Immunohistochemistry (IHC). Conclusion: The CAM xenograft model was successfully able to support the growth of CM and RB PDXs and their invasion in CAM, thus presenting as a feasible alternative to mammalian models for studying tumorigenicity and invasiveness of ocular tumors. Moreover, this model can further be utilized to develop personalized medicine by inoculating patient?specific tumors for preclinical drug screening.

3.
Artigo em Chinês | WPRIM | ID: wpr-1030732

RESUMO

Neuroblastoma (NB) is one of the most common malignant solid tumors in children, ranks fourth in the incidence of pediatric tumors, and accounts for 15% of pediatric tumor deaths in children in China. Despite the development of new treatment options, the prognosis for high-risk patients is still poor. An animal model that can replicate the tumorigenesis of NB is an important tool for the prevention and treatment of NB. However, there are currently no animal models that can simulate all features of human NB. To provide a reference for the construction of animal models and treatment of NB, this article introduced several animal models of NB that have been extensively researched: the mouse, chick embryo chorioallantoic membrane, and zebrafish models. At the same time, it elaborated on the species, construction methods, characteristics, advantages and disadvantages, and research progress in NB.

4.
Biosci. j. (Online) ; 38: e38086, Jan.-Dec. 2022. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1397491

RESUMO

The Hancornia speciosa latex has shown angiogenic activity. Angiogenesis plays a major role in wound healing, and materials that stimulate this process could be used to develop drugs. This study aimed to explain the role of proteins in the H. speciosa serum fraction latex in angiogenesis. Hence, this material was treated with proteinase K and the proteins were inactivated. After protein inactivation, angiogenic activity was assessed with the chick chorioallantoic membrane assay. The result showed that the proteins in the serum fraction are responsible for angiogenic activity. Then, the total protein content in the serum fraction and its enzymatic activity were investigated. The low protein content observed in the H. speciosa serum fraction latex suggests that this biomaterial could be used to develop new drugs with a hypoallergenic response. Despite the low protein content, there was a significant enzymatic activity of at least three enzymes in the serum fraction latex: ß-1,3 glucanase, ß-glucosidase, and proteases. These enzymes seem to influence the healing process, assisting debridement, extracellular matrix remodeling, and collagen deposition, and decreasing the chances of contamination by microorganisms. In conclusion, the enzymes in the H. speciosa serum latex are associated with the angiogenic activity of this biomaterial and may be used to assist the wound healing process.


Assuntos
Cicatrização , Endopeptidase K , Apocynaceae , Enzimas , Látex
5.
Acta Pharmaceutica Sinica B ; (6): 1853-1866, 2021.
Artigo em Inglês | WPRIM | ID: wpr-888838

RESUMO

Mitochondrial shape rapidly changes by dynamic balance of fusion and fission to adjust to constantly changing energy demands of cancer cells. Mitochondrial dynamics balance is exactly regulated by molecular motor consisted of myosin and actin cytoskeleton proteins. Thus, targeting myosin-actin molecular motor is considered as a promising strategy for anti-cancer. In this study, we performed a proof-of-concept study with a natural-derived small-molecule J13 to test the feasibility of anti-cancer therapeutics

6.
Braz. j. med. biol. res ; 54(3): e10291, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153518

RESUMO

The vascular network expansion and functioning are important factors affecting normal intra-uterine fetal development. This study addressed the previously reported antiangiogenic potential of beta-2-glycoprotein I (β2GPI) in vivo in the chick embryo model of angiogenesis. The effects of two naturally occurring β2GPI forms on the development of the chorioallantoic membrane (CAM) vessels and the chicken embryo were investigated. β2GPI monomers and dimers were obtained by fractioned purification and characterized using SDS-PAGE, immunoblot, and ELISA. The egg exposure was performed by injection of small volumes of 2.5 µg/mL solutions of the β2GPI subfractions. Angiogenesis was evaluated through quantitative measurements of vascular architecture parameters in the captured CAM images, using computational analysis of texture contrasts and computer vision techniques. Quantitative information was assigned to the CAM vasculature modifications. In vivo, the β2GPI dimer completely halted the formation of CAM vessels and led to embryo death after 48 h of exposure. The β2GPI monomer allowed the embryo to develop up to the 10th day, despite early changes of CAM vessels. The impaired normal vessel growth proceeded as a self-limited effect. The β2GPI monomer-exposed eggs showed reduced vascularization on the 6th day of incubation, but embryos were viable on the 10th day of incubation, with ingurgitated CAM vessels implying sequelae of the angiogenesis inhibition. Both subfractions impaired CAM vasculature development. The β2GPI dimer proved to be largely more harmful than the β2GPI monomer. β2GPI modification by cleavage or dimerization may play a role in angiogenesis control in vivo.


Assuntos
Galinhas , Membrana Corioalantoide , Embrião de Galinha , Neovascularização Fisiológica , Inibidores da Angiogênese/farmacologia , beta 2-Glicoproteína I
7.
Artigo | IMSEAR | ID: sea-206236

RESUMO

Allergic conjunctivitis (AC), defined by ocular itching, hyperemia, lacrimation and edema, impairs the quality of life across the globe. Ebastine is available as an oral antihistamine formula, such as tablets and syrup, for allergic disorders. Topical antihistamines are preferred over oral agents since their direct application at the site of action results in rapid onset and superior efficacy with less systemic side effects. The objective of the present work was to evaluate the antiallergic potential of optimized ebastine (1% w/v) colloidal ocular formulation by performing in vitro study like hen's egg chorioallantoic membrane test (HET-CAM) for tolerability and in vivo efficacy study in ovalbumin (OA)-induced allergic conjunctivitis (AC) with acute ocular irritation study. Eye scratching behavior and edema were evaluated after topical antigen challenge. Edema was scored at periodic interval after the instillation of ovalbumin followed by histopathology. The results showed that ebastine (1% w/v) colloidal ocular formulation was effective in inhibiting symptoms of eye inflammation induced by ovalbumin. Further, the study indicated that said formulation has a quick onset and the duration of effect sufficient to provide relief from symptoms for 24 hr. Ocular irritation by HET-CAM assay showed that the developed formulation does not cause any irritation to the blood vessels. Acute ocular irritation test was performed using rabbits and results showed that developed formulation was non-irritant to the eye. The present study revealed that the ocular ebastine formulation could offer a novel therapeutic opportunity against IgE-mediated allergic conjunctivitis.

8.
Artigo em Inglês | WPRIM | ID: wpr-758884

RESUMO

Monoclonal antibodies (MAbs) are widely applied in disease diagnoses. Herein, we report a MAb, WF-4, against Influenza A virus nucleoprotein (NP), its broad response with Influenza A virus, and its application in an immunohistochemistry (IHC) assay. WF-4 was screened by immunofluorescence assay (IFA). The results showed that its reactivity with baculovirus-expressed full-length recombinant NP (rNP) in Western blot (WB), indicating its IHC applicability. Fifteen Influenza A virus (reference subtypes H1 to H15) infected chicken embryonated chorioallantoic membranes (CAM), fixed by formalin, were all detectable in the WF-4-based IHC assay. Also, the reactivity of the IHC test with NP from experimentally inoculated H6N1 and from all recent outbreaks of H5 subtype avian Influenza A virus (AIV) field cases in Taiwan showed positive results. Our data indicate that CAM, a by-product of Influenza A virus preparation, is helpful for Influenza A virus-specific MAb characterization, and that the WF-4 MAb recognizes conserved and linear epitopes of Influenza A virus NP. Therefore, WF-4 is capable of detecting NP antigens via IHC and may be suitable for developing various tests for diagnosis of Influenza A virus and, especially, AIV infection.


Assuntos
Animais , Anticorpos Monoclonais , Western Blotting , Galinhas , Membrana Corioalantoide , Diagnóstico , Surtos de Doenças , Epitopos , Imunofluorescência , Formaldeído , Imuno-Histoquímica , Vírus da Influenza A , Influenza Aviária , Influenza Humana , Nucleoproteínas , Taiwan
9.
Acta cir. bras ; 34(12): e201901207, 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1054689

RESUMO

Abstract In the muscle invasive bladder cancer (MIBC) standard of care treatment only patients presenting a major pathological tumor response are more likely to show the established modest 5% absolute survival benefit at 5 years after cisplatin-based neoadjuvant chemotherapy (NAC). To overcome the drawbacks of a blind NAC (i.e. late cystectomy with unnecessary NAC adverse events) with potential to survival improvements, preclinical models of urothelial carcinoma have arisen in this generation as a way to pre-determine drug resistance even before therapy is targeted. The implantation of tumor specimens in the chorioallantoic membrane (MCA) of the chicken embryo results in a high-efficiency graft, thus allowing large-scale studies of patient-derived "tumor avatar". This article discusses a novel approach that exploits cancer multidrug resistance to provide personalized phenotype-based therapy utilizing the MIBC NAC dilemma.


Assuntos
Humanos , Animais , Neoplasias da Bexiga Urinária/tratamento farmacológico , Carcinoma/tratamento farmacológico , Urotélio/patologia , Membrana Corioalantoide/patologia , Neoplasias Experimentais/tratamento farmacológico , Fenótipo , Neoplasias da Bexiga Urinária/patologia , Carcinoma/patologia , Terapia Neoadjuvante , Ilustração Médica , Inoculação de Neoplasia , Neoplasias Experimentais/patologia
10.
Sci. med. (Porto Alegre, Online) ; 29(1): ID32157, 2019.
Artigo em Inglês | LILACS | ID: biblio-1009905

RESUMO

AIMS: To perform a physicochemical and phytochemical characterization of Jatropha curcas latex and to investigate its antiangiogenic potential. METHODS: We performed an initial physicochemical characterization of J. curcas latex using thermal gravimetric analyses and Fourier Transform Infrared spectroscopy. After that, phenols, tannins and flavonoids were quantified. Finally, the potential of J. curcas latex to inhibit angiogenesis was evaluated using the chick chorioallantoic membrane model. Five groups of 20 fertilized chicken eggs each had the chorioallantoic membrane exposed to the following solutions: (1) water, negative control; (2) dexamethasone, angiogenesis inhibitor; (3) Regederm®, positive control; (4) 25% J. curcas latex diluted in water; (5) 50% J. curcas latex diluted in water; and (6) J. curcas crude latex. Analysis of the newly-formed vascular net was made through captured images and quantification of the number of pixels. Histological analyses were performed to evaluate the inflammation, neovascularization, and hyperemia parameters. The results were statically analyzed with a significance level set at p<0.05. RESULTS: Physicochemical characterization showed that J. curcas latex presented a low amount of cis-1.4-polyisoprene, which reduced its elasticity and thermal stability. Phytochemical analyses of J. curcas latex identified a substantial amount of phenols, tannins, and flavonoids (51.9%, 11.8%, and 0.07% respectively). Using a chick chorioallantoic membrane assay, we demonstrated the antiangiogenic potential of J. curcas latex. The latex induced a decrease in the vascularization of the membranes when compared with neutral and positive controls (water and Regederm®). However, when compared with the negative control (dexamethasone), higher J. curcas latex concentrations showed no significant differences. CONCLUSIONS: J. curcas latex showed low thermal stability, and consisted of phenols, tannins, and flavonoids, but little or no rubber. Moreover, this latex demonstrated a significant antiangiogenic activity on a chick chorioallantoic membrane model. The combination of antimutagenic, cytotoxic, antioxidant and antiangiogenic properties makes J. curcas latex a potential target for the development of new drugs.


OBJETIVOS: Realizar uma caracterização físico-química e fitoquímica do látex de Jatropha curcas e investigar o seu potencial antiangiogênico. MÉTODOS: foi realizada uma caracterização físico-química inicial do látex de J. curcas utilizando as análises termogravimétricas e a espectroscopia com a Transformada de Fourier. Depois disso, fenóis, taninos e flavonoides foram quantificados. Finalmente, o potencial do látex de J. curcas em inibir a angiogênese foi avaliado através do uso de modelo de membrana corioalantoica de embrião de galinha. Cinco grupos, cada um com 20 ovos de galinha fertilizados, tiveram a membrana corioalantoica exposta às seguintes soluções: (1) água, controle negativo; (2) dexametasona, inibidor da angiogênese; (3) Regederm®, controle positivo; (4) 25% de látex de J. curcas diluído em água; (5) 50% de látex de J. curcas diluído em água; e (6) látex bruto de J. curcas. A análise da rede vascular recém-formada foi feita por meio de imagens capturadas e quantificação do número de pixels. Análises histológicas foram realizadas para avaliar os parâmetros de inflamação, neovascularização e hiperemia. Os resultados foram analisados estaticamente com nível de significância estabelecido em p<0,05. RESULTADOS: A caracterização físico-química mostrou que o látex de J. curcas apresenta uma baixa quantidade de cis-1,4-poliisopreno, o que reduz sua elasticidade e estabilidade térmica. Análises fitoquímicas do látex de J. curcas identificaram uma quantidade significativa de fenóis, taninos e flavonoides (51,9%, 11,8% e 0,07% respectivamente). Usando o modelo de membrana corioalantoica de ovo de galinha embrionado, demonstrou-se o potencial antiangiogênico do látex de J. curcas. O látex induziu a diminuição da vascularização das membranas, em comparação aos grupos controle neutro e positivo (água e Regederm®). CONCLUSÕES: O látex de J. curcas apresentou baixa estabilidade térmica, ausência ou pouca quantidade de borracha e presença de fenóis, taninos e flavonoides em sua composição. Além disso, apresentou alta atividade antiangiogênica no modelo de membrana corioalantoica de embrião de galinha. A combinação de propriedades antimutagênicas, citotóxicas, anti-inflamatórias, antioxidantes e antiangiogênicas faz com que o látex de J. curcas seja um alvo potencial para o desenvolvimento de novos medicamentos.


Assuntos
Preparações Farmacêuticas , Farmacologia , Jatropha
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