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1.
Pharmaceutics ; 16(9)2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39339213

RESUMEN

Melanoma, the most aggressive form of skin cancer, presents a major clinical challenge due to its tendency to metastasize and recalcitrance to traditional therapies. Despite advances in surgery, chemotherapy, and radiotherapy, the outlook for advanced melanoma remains bleak, reinforcing the urgent need for more effective treatments. Photodynamic therapy (PDT) has emerged as a promising alternative, leading to targeted tumor destruction with minimal harm to surrounding tissues. In this study, the direct and abscopal antitumor effects of PDT in a bilateral murine melanoma model were evaluated. Although only one of the two tumors was treated, effects were observed in both. Our findings revealed significant changes in systemic inflammation and alterations in CD4+ and CD8+ T cell populations in treated groups, as evidenced by blood analyses and flow cytometry. High-throughput RNA sequencing (RNA-Seq) further unveiled shifts in gene expression profiles in both treated and untreated tumors. This research sheds light on the novel antitumor and abscopal effects of nanoemulsion of aluminum chloride phthalocyanine (AlPcNE)-mediated PDT in melanoma, highlighting the potential of different PDT protocols to modulate immune responses and to achieve more effective and targeted cancer treatments.

2.
Nanomedicine (Lond) ; 19(23): 1895-1911, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39109488

RESUMEN

Aim: Breast cancer and its metastases involve high mortality even with advances in chemotherapy. Solid lipid nanoparticles provide a platform for drug delivery, reducing side effects and treatment-induced bone loss. A solid nanoparticle containing doxorubicin was evaluated for its ability to prevent bone loss in a pre-clinical breast cancer model.Methods: We investigated the effects of SLNDox in an aggressive metastatic stage IV breast cancer model, which has some important features that are interesting for bone loss investigation. This study evaluates bone loss prevention potential from solid lipid nanoparticles containing doxorubicin breast cancer treatment, an evaluation of the attenuation of morphological changes in bone tissue caused by the treatment and the disease and an assessment of bone loss imaging using computed tomography and electron microscopy.Results: Chemotherapy-induced bone loss was also observed in tumor-free animals; a solid lipid nanoparticle containing doxorubicin prevented damage to the growth plate and to compact and cancellous bones in the femur of tumor-bearing and healthy animals.Conclusion: The association of solid lipid nanoparticles with chemotherapeutic drugs with proven efficacy promotes the prevention of serious consequences of chemotherapy, reducing tumor progression, increasing quality of life and improving prognosis and survival.


[Box: see text].


Asunto(s)
Doxorrubicina , Nanopartículas , Doxorrubicina/administración & dosificación , Animales , Femenino , Nanopartículas/química , Humanos , Neoplasias de la Mama/tratamiento farmacológico , Ratones , Lípidos/química , Línea Celular Tumoral , Portadores de Fármacos/química , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/farmacología , Liposomas
3.
Pharmaceutics ; 16(7)2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39065638

RESUMEN

Photodynamic therapy (PDT) uses a photosensitizer to generate reactive oxygen species (ROS) that kill target cells. In cancer treatments, PDT can potentially induce immunogenic cell death (ICD), which is characterized by a well-controlled exposure of damage-associated molecular patterns (DAMPs) that activate dendritic cells (DCs) and consequently modulate the immune response in the tumor microenvironment. However, PDT still has limitations, such as the activity of photosensitizers in aqueous media and poor bioavailability. Therefore, a new photosensitizer system, SLN-AlPc, has been developed to improve the therapeutic efficacy of PDT. In vitro experiments showed that the light-excited nanocarrier increased ROS production in murine melanoma B16-F10 cells and modulated the profile of DCs. PDT induced cell death accompanied by the exposure of DAMPs and the formation of autophagosomes. In addition, the DCs exposed to PDT-treated B16-F10 cells exhibited morphological changes, increased expression of MHCII, CD86, CD80, and production of IL-12 and IFN-γ, suggesting immune activation towards an antitumor profile. These results indicate that the SLNs-AlPc protocol has the potential to improve PDT efficacy by inducing ICD and activating DCs.

4.
Sci Rep ; 14(1): 11242, 2024 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755230

RESUMEN

The interaction of Plasmodium falciparum-infected red blood cells (iRBCs) with the vascular endothelium plays a crucial role in malaria pathology and disease. KAHRP is an exported P. falciparum protein involved in iRBC remodelling, which is essential for the formation of protrusions or "knobs" on the iRBC surface. These knobs and the proteins that are concentrated within them allow the parasites to escape the immune response and host spleen clearance by mediating cytoadherence of the iRBC to the endothelial wall, but this also slows down blood circulation, leading in some cases to severe cerebral and placental complications. In this work, we have applied genetic and biochemical tools to identify proteins that interact with P. falciparum KAHRP using enhanced ascorbate peroxidase 2 (APEX2) proximity-dependent biotinylation and label-free shotgun proteomics. A total of 30 potential KAHRP-interacting candidates were identified, based on the assigned fragmented biotinylated ions. Several identified proteins have been previously reported to be part of the Maurer's clefts and knobs, where KAHRP resides. This study may contribute to a broader understanding of P. falciparum protein trafficking and knob architecture and shows for the first time the feasibility of using APEX2-proximity labelling in iRBCs.


Asunto(s)
Eritrocitos , Plasmodium falciparum , Proteómica , Proteínas Protozoarias , Eritrocitos/parasitología , Eritrocitos/metabolismo , Plasmodium falciparum/metabolismo , Proteínas Protozoarias/metabolismo , Humanos , Proteómica/métodos , Malaria Falciparum/parasitología , Malaria Falciparum/metabolismo , ADN-(Sitio Apurínico o Apirimidínico) Liasa/metabolismo , Ascorbato Peroxidasas/metabolismo , Unión Proteica , Biotinilación , Endonucleasas , Péptidos , Proteínas , Enzimas Multifuncionales
5.
Pharmaceuticals (Basel) ; 16(12)2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38139786

RESUMEN

Melanoma, a severe form of skin cancer intricately linked to genetic and environmental factors, is predicted to reach 100,000 new cases worldwide by 2040, underscoring the need for effective and safe treatment options. In this study, we assessed the efficacy of a photosensitizer called Chlorophyll A (Chl-A) incorporated into hydrogels (HGs) made of chitosan (CS) and poloxamer 407 (P407) for Photodynamic Therapy (PDT) against the murine melanoma cell line B16-F10. The HG was evaluated through various tests, including rheological studies, SEM, and ATR-FTIR, along with cell viability assays. The CS- and P407-based HGs effectively released Chl-A and possessed the necessary properties for topical application. The photodynamic activity of the HG containing Chl-A was evaluated in vitro, demonstrating high therapeutic potential, with an IC50 of 25.99 µM-an appealing result when compared to studies in the literature reporting an IC50 of 173.8 µM for cisplatin, used as a positive control drug. The developed formulation of CS and P407-based HG, serving as a thermosensitive system for topical applications, successfully controlled the release of Chl-A. In vitro cell studies associated with PDT exhibited potential against the melanoma cell line.

6.
Biomolecules ; 13(3)2023 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-36979510

RESUMEN

The number of multidrug-resistant pathogenic microorganisms has been growing in recent years, most of which is due to the inappropriate use of the commercial antibiotics that are currently available. The dissemination of antimicrobial resistance represents a serious global public health problem. Thus, it is necessary to search for and develop new drugs that can act as antimicrobial agents. Antimicrobial peptides are a promising alternative for the development of new therapeutic drugs. Anurans' skin glands are a rich source of broad-spectrum antimicrobial compounds and hylids, a large and diverse family of tree frogs, are known as an important source of antimicrobial peptides. In the present study, two novel antimicrobial peptides, named Raniseptins-3 and -6, were isolated from Boana raniceps skin secretion and their structural and biological properties were evaluated. Raniseptins-3 and -6 are cationic, rich in hydrophobic residues, and adopt an α-helix conformation in the presence of SDS (35 mM). Both peptides are active against Gram-negative bacteria and Gram-positive pathogens, with low hemolytic activity at therapeutic concentrations. No activity was observed for yeasts, but the peptides are highly cytotoxic against B16F10 murine melanoma cells and NIH3T3 mouse fibroblast cells. None of the tested compounds showed improvement trends in the MTT and LDH parameters of MHV-3 infected cells at the concentrations tested.


Asunto(s)
Antiinfecciosos , Péptidos Catiónicos Antimicrobianos , Animales , Ratones , Péptidos Catiónicos Antimicrobianos/farmacología , Péptidos Catiónicos Antimicrobianos/química , Péptidos Antimicrobianos , Células 3T3 NIH , Antiinfecciosos/farmacología , Antiinfecciosos/química , Anuros , Antibacterianos/farmacología , Antibacterianos/análisis , Pruebas de Sensibilidad Microbiana , Piel/química
7.
Nanomaterials (Basel) ; 12(20)2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36296737

RESUMEN

Photodynamic therapy (PDT) mediated by photosensitizers loaded in nanostructures as solid lipid nanoparticles has been pinpointed as an effective and safe treatment against different skin cancers. Amazon butters have an interesting lipid composition when it comes to forming solid lipid nanoparticles (SLN). In the present report, a new third-generation photosensitizing system consisting of aluminum-phthalocyanine associated with Amazon butter-based solid lipid nanoparticles (SLN-AlPc) is described. The SLN was developed using murumuru butter, and a monodisperse population of nanodroplets with a hydrodynamic diameter of approximately 40 nm was obtained. The study of the permeation of these AlPc did not permeate the analyzed skin, but when incorporated into the system, SLN-AlPc allowed permeation of almost 100% with 8 h of contact. It must be emphasized that SLN-AlPc was efficient for carrying aluminum-phthalocyanine photosensitizers and exhibited no toxicity in the dark. Photoactivated SLN-AlPc exhibited a 50% cytotoxicity concentration (IC50) of 19.62 nM when applied to B16-F10 monolayers, and the type of death caused by the treatment was apoptosis. The exposed phospholipid phosphatidylserine was identified, and the treatment triggered a high expression of Caspase 3. A stable Amazon butter-based SLN-AlPc formulation was developed, which exhibits strong in vitro photodynamic activity on melanoma cells.

9.
Front Cell Infect Microbiol ; 12: 879018, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35755848

RESUMEN

Chromoblastomycosis (CBM) is a chronic cutaneous and subcutaneous mycosis caused by black, dimorphic, and filamentous fungi of the Herpothrichiellaceae family, such as species of the genus Fonsecaea. These fungi can switch between the saprophytic forms (conidia and hyphae) and the pathogenic form, the muriform cells (MCs), which is considered an essential mechanism for fungal virulence. Nearly all types of cells can produce membranous structures formed by a lipid bilayer that communicate extracellularly with other cells, known as "extracellular vesicles" (EVs), which may act as virulence factors, as observed for several species of pathogenic fungi. Our findings demonstrated for the first time that F. pedrosoi, F. nubica, and F. erecta produce EVs in response to nutritional conditions. The EVs varied in sterol and protein contents, size, and morphology. Moreover, the EVs induced different cytokine and nitric oxide release patterns by bone marrow-derived macrophages (BMDMs). The EVs activated IL-1ß production, possibly acting as the first signal in inflammasome activation. Unlike the pathogenic species, the EVs isolated from F. erecta did not significantly stimulate TNF and IL-10 production in general. Overall, these results demonstrated that different species of Fonsecaea produce EVs capable of modulating pro- and anti-inflammatory cytokine and nitric oxide production by BMDMs and that growth conditions affected the immunomodulatory capacities of the EVs as well as their size, content, and morphology.


Asunto(s)
Ascomicetos , Cromoblastomicosis , Vesículas Extracelulares , Cromoblastomicosis/microbiología , Cromoblastomicosis/patología , Citocinas , Fonsecaea , Macrófagos , Óxido Nítrico , Virulencia
10.
Nanomedicine (Lond) ; 17(27): 2073-2088, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36853205

RESUMEN

Aim: Investigate the heterogeneous tumor tissue organization and examine how this condition can interfere with the passive delivery of a lipid nanoemulsion in two breast cancer preclinical models (4T1 and Ehrlich). Materials & methods: The authors used in vivo image techniques to follow the nanoemulsion biodistribution and microtomography, as well as traditional histopathology and electron microscopy to evaluate the tumor structural characteristics. Results & conclusion: Lipid nanoemulsion was delivered to the tumor, vascular organization depends upon the subtumoral localization and this heterogeneous organization promotes a nanoemulsion biodistribution to the highly vascular peripherical region. Also, the results are presented with a comprehensive mathematical model, describing the differential biodistribution in two different breast cancer models, the 4T1 and Ehrlich models.


Asunto(s)
Neoplasias de la Mama , Nanopartículas , Humanos , Femenino , Línea Celular Tumoral , Distribución Tisular , Nanopartículas/química , Lípidos , Neoplasias de la Mama/diagnóstico por imagen , Emulsiones/química
11.
Anim Biotechnol ; 33(6): 1014-1024, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33380273

RESUMEN

Cells from different origins behave differently regarding the incorporation of exogenous DNA and formation of transgenic cells. Milk production of recombinant antibody may benefit from efficient transfection protocols to produce transgenic animals. In this context, the objective of this study was to verify the transfection potential of bovine mesenchymal stem cells from Wharton's jelly (MSC-WJ) and adipose tissue (MSC-AT), comparing co-transfection protocols with vectors pBC1-anti-CD3 and pEF-NEO-GFP, using transfection reagents Lipofectamine LTX with Plus Reagent or Xfect. Skin fibroblasts (FIB) were used as the control group. Forty-eight hours after transfection, neomycin was added and cells cultured for 2 weeks. Treated cells were submitted to fluorescence microscopy, flow cytometry, and PCR evaluations. Wharton's jelly cells were sensitive to treatments and started necrosis. In the flow cytometry assay, the median fluorescence was higher in adipocytes than fibroblasts, for both the Xfect (20.057 ± 1.620,7 and 10.601 ± 702,86, respectively, p < 0.05) and LTX (19.590 ± 113,84 and 10.518 ± 442,65, respectively, p < 0.05). These results, associated with evaluation of epifluorescence, demonstrated that adipocytes presented a better response to transfection than other cells, independent of the kit used. Performing PCR on co-transfected cells demonstrated the presence of anti-CD3, making this approach feasible for future experiments.


Asunto(s)
Células Madre Mesenquimatosas , Gelatina de Wharton , Bovinos , Animales , Células Cultivadas , Gelatina de Wharton/metabolismo , Transfección , Adipocitos , Diferenciación Celular
12.
Oncotarget ; 12(19): 1920-1936, 2021 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-34548908

RESUMEN

Triple-negative breast cancer (TNBC) constitutes a very aggressive type of breast cancer with few options of cytotoxic chemotherapy available for them. A chemotherapy regimen comprising of doxorubicin hydrochloride and cyclophosphamide, followed by paclitaxel, known as AC-T, is approved for usage as an adjuvant treatment for this type of breast cancer. In this study we aimed to elucidate the role of KIF11 in TNBC progression throughout its inhibition by two synthetic small molecules containing the DHPM core (dihydropyrimidin-2(1H)-ones or -thiones), with the hypothesis that these inhibitors could be an interesting option of antimitotic drug used alone or as adjuvant therapy in association with AC. For this purpose, we evaluated the efficacy of DHPMs used as monotherapy or in combination with doxorubicin and cyclophosphamide, in Balbc-nude mice bearing breast cancer induced by MDA-MB-231, having AC-T as positive control. Our data provide extensive evidence to demonstrate that KIF11 inhibitors showed pronounced antitumor activity, acting in key points of tumorigenesis and cancer progression in in vivo xenograft model of triple negative breast cancer, like down-regulation of KIF11 and ALDH1-A1. Moreover, they didn't show the classic peripheral neuropathy characterized by impaired mobility, as it is common with paclitaxel use. These results suggest that the use of a MAP inhibitor in breast cancer regimen treatment could be a promising strategy to keep antitumoral activity reducing the side effects.

13.
Top Companion Anim Med ; 41: 100463, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32823162

RESUMEN

Green iguanas are arboreal lizards, common as pet animals and in captivity. Knowledge of neoplasms in iguanas is scarce, and a challenge to their prevention, treatment, and prognosis. A captive green iguana showed a pigmented nasal exophytic neoplasm. Tumor cells were spindle-shaped to epithelioid with a variable amount of dark-brown or black granular melanin within the cytoplasm, and also presented cytoplasmic positivity for Melan-A and S100. Transmission electron microscopy evidenced intracytoplasmic melanosomes and premelanosomes and provided a definitive diagnosis of a nasal melanophoroma. Full characterization of the clinicopathological and ultrastructural features of the melanophoroma may contribute to the limited knowledge concerning cutaneous neoplasms in green iguanas.


Asunto(s)
Iguanas , Neoplasias Nasales/veterinaria , Animales , Femenino , Microscopía Electrónica de Transmisión , Neoplasias Nasales/patología , Neoplasias Nasales/cirugía , Neoplasias Nasales/ultraestructura
14.
J Nanobiotechnology ; 18(1): 43, 2020 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-32164731

RESUMEN

BACKGROUND: Metastasis causes the most breast cancer-related deaths in women. Here, we investigated the antitumor effect of solid lipid nanoparticles (SLN-DTX) when used in the treatment of metastatic breast tumors using 4T1-bearing BALB/c mice. RESULTS: Solid lipid nanoparticles (SLNs) were produced using the high-energy method. Compritol 888 ATO was selected as the lipid matrix, and Pluronic F127 and Span 80 as the surfactants to stabilize nanoparticle dispersion. The particles had high stability for at least 120 days. The SLNs' dispersion size was 128 nm, their polydispersity index (PDI) was 0.2, and they showed a negative zeta potential. SLNs had high docetaxel (DTX) entrapment efficiency (86%), 2% of drug loading and showed a controlled drug-release profile. The half-maximal inhibitory concentration (IC50) of SLN-DTX against 4T1 cells was more than 100 times lower than that of free DTX after 24 h treatment. In the cellular uptake test, SLN-DTX was taken into the cells significantly more than free DTX. The accumulation in the G2-M phase was significantly higher in cells treated with SLN-DTX (73.7%) than in cells treated with free DTX (23.0%), which induced subsequent apoptosis. TEM analysis revealed that SLN-DTX internalization is mediated by endocytosis, and fluorescence microscopy showed DTX induced microtubule damage. In vivo studies showed that SLN-DTX compared to free docetaxel exhibited higher antitumor efficacy by reducing tumor volume (p < 0.0001) and also prevented spontaneous lung metastasis in 4T1 tumor-bearing mice. Histological studies of lungs confirmed that treatment with SLN-DTX was able to prevent tumor. IL-6 serum levels, ki-67 and BCL-2 expression were analyzed and showed a remarkably strong reduction when used in a combined treatment. CONCLUSIONS: These results indicate that DTX-loaded SLNs may be a promising carrier to treat breast cancer and in metastasis prevention.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Docetaxel/farmacología , Lípidos/farmacología , Neoplasias Pulmonares/tratamiento farmacológico , Nanopartículas/química , Animales , Apoptosis/efectos de los fármacos , Modelos Animales de Enfermedad , Portadores de Fármacos/farmacología , Ácidos Grasos/farmacología , Femenino , Hexosas/farmacología , Concentración 50 Inhibidora , Ratones , Ratones Endogámicos BALB C , Células 3T3 NIH , Tamaño de la Partícula , Poloxámero/farmacología
15.
Carbohydr Polym ; 227: 115351, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31590861

RESUMEN

Surfactants have been used as a tool to improve the properties of polymeric nanoparticles (NPs) and to increase the rate of hydrophobic drug release by means of these nanoparticles. In this context, this study evaluated the effect of lecithin on the characteristics of chitosan (CHI) and chondroitin sulfate (CS) nanoparticles, when applied in curcumin (Curc) release. CHI/CS NPs and CHI/CS/Lecithin NPs were prepared by the ionic gelation method, both as standards and containing curcumin. Simultaneous conductimetric and potentiometric titrations were employed to optimize the interaction between the polymers. NPs with hydrodynamic diameter of ∼130 nm and zeta potential of +60 mV were obtained and characterized by HRTEM; their pore size and surface area were also analyzed by BET method, DLS, FTIR, XPS, and fluorescence spectroscopy techniques to assess morphological and surface properties, stability and interaction between polymers and to quantify the loading of drugs. The final characteristics of NPs were directly influenced by lecithin addition, exhibiting enhanced encapsulation efficiency of curcumin (131.8 µg curcumin per mg CHI/CS/Lecithin/Curc NPs). The release of curcumin occurred gradually through a two-stage process: diffusion-controlled dissolution and release of curcumin controlled by dissolution of the polymer. However, the release of curcumin in buffer solution at pH 7.4 was achieved faster in CHI/CS/Lecithin/Curc NPs than in CHI/CS/Curc NPs. in vitro cytotoxic activity evaluation of the curcumin was determined by the MTT assay, observing that free curcumin and curcumin nanoencapsulated in CHI/CS/Curc and CHI/CS/Lecithin/Curc NPs reduced the viability of MCF-7 cells in the 72 h period (by 28.4, 36.0 and 30.7%, P < 0.0001, respectively). These results indicate that CHI/CS/Lecithin NPs have more appropriate characteristics for encapsulation of curcumin.


Asunto(s)
Quitosano/química , Sulfatos de Condroitina/química , Curcumina/química , Lecitinas/química , Nanopartículas/química , Supervivencia Celular/efectos de los fármacos , Quitosano/administración & dosificación , Sulfatos de Condroitina/administración & dosificación , Curcumina/administración & dosificación , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/química , Liberación de Fármacos , Humanos , Lecitinas/administración & dosificación , Células MCF-7 , Nanopartículas/administración & dosificación
16.
Rev. bras. oftalmol ; 78(4): 227-232, July-Aug. 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1013679

RESUMEN

Abstract Objective: The aim of this study is to identify the causes for discarding corneas at the Eye Bank of the Federal District in Brasilia, Brazil, and describe the social and demographic variables and Causa Mortis of cornea donors from 2014 to 2017. Methods: We conducted an exploratory and social-epidemiologic descriptive study regarding cornea donation. The data base information was obtained from the corneal donor's medical records analysis. All of the potential donors' records (cause of death, cause of cornea discard, month of donation, age, gender, and time of death, corneal enucleation and preservation), from 2014 to 2017 were included in the study. Results: We looked at 1,574 corneal donor notifications. Demographic characteristics displayed significant differences in gender distribution (male, 74.8% and female, 25.2%), and the average donor age was 40 ± 15.9 years. 25% of the causes of death were from cardiovascular disease followed by 19.6% from sharp or blunt instrument injury, 14.2% resulted from multiple traumas. We described 3,074 donated corneas from the DF Eye Bank, where 2.6% has not been uptaken. Of those 3,074 corneal tissues, nearly 60% (n=1,836) have been transplanted and 40% (n=1,238) were discarded. Regarding the causes of discard, 68% (n=841) were due to positive or indeterminate serological blood tests and 39% (n=486) because of matureness (expired medium guaranteed period of corneal preservation). Conclusions: Specific issues such as violent causes of death, gender disproportion and total time of corneal processing can be better managed to reduce procurement times, and availability, of corneal tissue for transplantation.


Resumo Objetivo: Identificar as causas do descarte de córneas no Banco de Olhos do Distrito Federal, em Brasília, Brasil, descrever as variáveis sociodemográficas e causa de morte dos doadores de córnea de 2014 a 2017. Métodos: Foi realizado um estudo descritivo exploratório e socioepidemiológico sobre as doações de córnea. As informações da base de dados foram obtidas a partir da análise dos prontuários dos doadores. Todos os registros dos potenciais doadores (causa da morte, causa do descarte, mês de doação, idade, sexo e tempo de morte, enucleação e preservação da córnea), de 2014 a 2017, foram incluídos no estudo. Resultados: Analisamos 1.574 notificações de doadores. Características demográficas apresentaram diferenças significativas na distribuição por sexo (masculino, 74,8% e feminino, 25,2%). A idade média dos doadores foi de 40 ± 15,9 anos. 25% das causas de morte foram de doenças cardiovasculares, seguidas de 19,6% de perfurações por arma de fogo e 14,2% de múltiplos traumas. Descrevemos as 3.074 córneas doadas ao Banco de Olhos do DF e onde apenas 2,6% não foram captadas. Dos 3.074 tecidos da córnea, quase 60% (n = 1.836) foram transplantados e 40% (n = 1.238) foram descartados. Quanto às causas de descarte, 68% (n = 841) foram devidas a exames sorológicos positivos ou indeterminados e 39% (n = 486) por tempo de vencimento (período máximo de preservação da córnea). Conclusões: Questões específicas como causas violentas de morte, desproporção de gênero e tempo total de processamento da córnea podem ser melhor gerenciadas para reduzir o tempo de captação e a disponibilidade de tecido para transplante.


Asunto(s)
Humanos , Donantes de Tejidos/estadística & datos numéricos , Obtención de Tejidos y Órganos/estadística & datos numéricos , Causas de Muerte , Trasplante de Córnea/estadística & datos numéricos , Selección de Paciente , Bancos de Ojos/estadística & datos numéricos , Preservación de Órganos , Obtención de Tejidos y Órganos/normas , Registros Médicos , Epidemiología Descriptiva , Córnea
17.
Reprod Domest Anim ; 54(2): 289-299, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30317681

RESUMEN

The aim of this work was to investigate the methylation and hydroxymethylation status of mesenchymal stem cells (MSC) from amniotic fluid (MSC-AF), adipose tissue (MSC-AT) and fibroblasts (FIB-control) and to verify the effect of trichostatin A (TSA) on gene expression and development of cloned bovine embryos produced using these cells. Characterization of MSC from two animals (BOV1 and BOV2) was performed by flow cytometry, immunophenotyping and analysis of cellular differentiation genes expression. The cells were used in the nuclear transfer in the absence or presence of 50 nM TSA for 20 hr in embryo culture. Expression of HDAC1, HDAC3 and KAT2A genes was measured in embryos by qRT-PCR. Methylation results showed difference between animals, with MSC from BOV2 demonstrating lower methylation rate than BOV1. Meanwhile, MSC-AF were less hydroxymethylated for both animals. MSC-AF from BOV2 produced 44.92 ± 8.88% of blastocysts when embryos were exposed to TSA and similar to embryo rate of MSC-AT also treated with TSA (37.96 ± 15.80%). However, when methylation was lower in FIB compared to MSC, as found in BOV1, the use of TSA was not sufficient to increase embryo production. MSC-AF embryos expressed less HDAC3 when treated with TSA, and expression of KAT2A was higher in embryos produced with all MSC and treated with TSA than embryos produced with FIB. The use of MSC less methylated and more hydroxymethylated in combination with embryo incubation with TSA can induce lower expression of HDAC3 and higher expression of KAT2A in the embryos and consequently improve bovine embryo production.


Asunto(s)
Histona Acetiltransferasas/metabolismo , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/metabolismo , Ácidos Hidroxámicos/farmacología , Células Madre Mesenquimatosas/citología , Acetilación , Animales , Bovinos , Clonación de Organismos/métodos , Clonación de Organismos/veterinaria , Metilación de ADN , Embrión de Mamíferos/embriología , Desarrollo Embrionario , Epigénesis Genética , Femenino , Regulación del Desarrollo de la Expresión Génica , Histona Acetiltransferasas/genética , Histona Desacetilasas/genética , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Técnicas de Transferencia Nuclear/veterinaria
18.
Mater Sci Eng C Mater Biol Appl ; 92: 184-195, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30184741

RESUMEN

Remotely assisted drug delivery by means of magnetic biopolymeric nanoplatforms has been utilized as an important tool to improve the delivery/release of hydrophobic drugs and to address their low cargo capacity. In this work, MnFe2O4 magnetic nanoparticles (MNPs) were synthesized by thermal decomposition, coated with citrate and then functionalized with the layer-by-layer (LbL) assembly of polyelectrolyte multilayers, with chitosan as polycation and sodium alginate as polyanion. Simultaneous conductimetric and potentiometric titrations were employed to optimize the LbL deposition and to enhance the loading capacity of nanoplatforms for curcumin, a hydrophobic drug used in cancer treatment. ~200 nm sized biopolymer platforms with ~12 nm homogeneously embedded MNPs were obtained and characterized by means of XRD, HRTEM, DLS, TGA, FTIR, XPS and fluorescence spectroscopy techniques to access structural, morphological and surface properties, to probe biopolymer functionalization and to quantify drug-loading. Charge reversals (±30 mV) after each deposition confirmed polyelectrolyte adsorption and a stable LbL assembly. Magnetic interparticle interaction was reduced in the biopolymeric structure, hinting at an optimized performance in magnetic hyperthermia for magneto-assisted drug release applications. Curcumin was encapsulated, resulting in an enhanced payload (~100 µg/mg). Nanocytotoxicity assays showed that the biopolymer capping enhanced the biocompatibility of nanoplatforms, maintaining entrapped curcumin. Our results indicate the potential of synthesized nanoplatforms as an alternative way of remotely delivering/releasing curcumin for medical purposes, upon application of an alternating magnetic field, demonstrating improved efficiency and reduced toxicity.


Asunto(s)
Alginatos/química , Quitosano/química , Curcumina/química , Compuestos Férricos/química , Nanopartículas de Magnetita/química , Compuestos de Manganeso/química , Materiales Biocompatibles/química , Supervivencia Celular/efectos de los fármacos , Curcumina/metabolismo , Curcumina/farmacología , Portadores de Fármacos/química , Liberación de Fármacos , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Humanos , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Células MCF-7 , Tamaño de la Partícula
19.
J Nanosci Nanotechnol ; 18(1): 522-528, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29768877

RESUMEN

Due to the low therapeutic index of different chemotherapeutic drugs used for cancer treatment, the development of new anticancer drugs remains an intense field of research. A recently developed mixture of selenitetriacylglycerides, selol, was shown to be active against different cancer cells in vitro. As this compound is highly hydrophobic, it was encapsulated, in a previous study, into poly(methyl vinyl ether-co-maleic anhydride)-shelled nanocapsules in order to improve its dispersibility in aqueous media. Following this line of research, the present report aimed at enhancing the In Vitro activity of the selol nanocapsules against cancerous cells by decorating their surface with folic acid. It is known that several cancer cells overexpress folate receptors. Stable folic acid-decorated selol nanocapsules (SNP-FA) were obtained, which showed to be spherical, with a hydro-dynamic diameter of 364 nm, and zeta potential of -24 mV. In comparison to non-decorated selol nanocapsules, SNP-FA presented higher activity against 4T1, MCF-7 and HeLa cells. Moreover, the decoration of the nanocapsules did not alter their toxicity towards fibroblasts, NIH-3T3 cells. These results show that the decoration with folic acid increased the toxicity of selol nanocapsules to cancer cells. These nanocapsules, besides enabling to disperse selol in an aqueous medium, increased the toxicity of this drug In Vitro, and may be useful to treat cancer in vivo, potentially increasing the specificity of selol towards cancer cells.


Asunto(s)
Nanocápsulas , Neoplasias , Compuestos de Selenio , Animales , Línea Celular Tumoral , Ácido Fólico , Células HeLa , Humanos , Maleatos , Ratones , Neoplasias/tratamiento farmacológico , Polietilenos
20.
J Nanobiotechnology ; 16(1): 9, 2018 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-29382332

RESUMEN

BACKGROUND: In the photodynamic therapy (PDT), the photosensitizer absorbs light and transfers the energy of the excited state to the oxygen in the cell environment producing reactive oxygen species (ROS), that in its turn, may cause cell damage. In the photothermal therapy (PTT), light also is responsible for activating the photothermal agent, which converts the absorbed energy in heat. Graphene oxide is a carbon-based material that presents photothermal activity. Its physical properties allow the association with the photosensitizer methylene blue and consequently the production of ROS when submitted to light irradiation. Therefore, the association between nanographene oxide and methylene blue could represent a strategy to enhance therapeutic actions. In this work, we report the nanographene oxide-methylene blue platform (NanoGO-MB) used to promote tumor ablation in combination with photodynamic and photothermal therapies against a syngeneic orthotopic murine breast cancer model. RESULTS: In vitro, NanoGO-MB presented 50% of the reactive oxygen species production compared to the free MB after LED light irradiation, and a temperature increase of ~ 40 °C followed by laser irradiation. On cells, the ROS production by the nanoplatform displayed higher values in tumor than normal cells. In vivo assays demonstrated a synergistic effect obtained by the combined PDT/PTT therapies using NanoGO-MB, which promoted complete tumor ablation in 5/5 animals. Up to 30 days after the last treatment, there was no tumor regrowth compared with only PDT or PTT groups, which displayed tumoral bioluminescence 63-fold higher than the combined treatment group. Histological studies confirmed that the combined therapies were able to prevent tumor regrowth and liver, lung and spleen metastasis. In addition, low systemic toxicity was observed in pathologic examinations of liver, spleen, lungs, and kidneys. CONCLUSIONS: The treatment with combined PDT/PTT therapies using NanoGO-MB induced more toxicity on breast carcinoma cells than on normal cells. In vivo, the combined therapies promoted complete tumor ablation and metastasis prevention while only PDT or PTT were unable to stop tumor development. The results show the potential of NanoGO-MB in combination with the phototherapies in the treatment of the breast cancer and metastasis prevention.


Asunto(s)
Técnicas de Ablación , Grafito/química , Neoplasias Mamarias Animales/tratamiento farmacológico , Neoplasias Mamarias Animales/patología , Azul de Metileno/química , Nanopartículas/química , Fototerapia , Animales , Apoptosis , Peso Corporal , Línea Celular Tumoral , Supervivencia Celular , Modelos Animales de Enfermedad , Femenino , Inmunohistoquímica , Luminiscencia , Neoplasias Mamarias Animales/prevención & control , Ratones , Ratones Endogámicos BALB C , Células 3T3 NIH , Nanopartículas/ultraestructura , Metástasis de la Neoplasia , Fotoquimioterapia , Especies Reactivas de Oxígeno , Carga Tumoral
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