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1.
Anim Reprod ; 21(1): e20230155, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628495

RESUMO

The adnexa fetal tissues are sources of mesenchymal stromal cells (MSCs) due to their noninvasive harvest, with all biological material discarded most of the time. MSCs are a promise regarding to their plasticity, self-renewal, differentiation potentials, immunomodulatory and anti-inflammatory properties, which have made clinical stem cell therapy a reality. The present study aimed to characterize and evaluate the immunomodulation ability of bovine mesenchymal cells collected from bovine amniotic fluid (bAFMSCs) isolated and subjected to sixth consecutive culture passages in vitro. The multilineage properties of the bAFMSCs collections confirmed the ability to undergo adipogenic, chondrogenic and osteogenic differentiation. The mesenchymal gene transcription CD106, CD73, CD29, CD90 and CD166 were detected in bAFMSCs, whereas CD34 and CD45 were not detected. Regarding cytokine mRNA expression, IL2, IL6, INFα, INFß, INFγ, TNFα and TNFß were downregulated, while IL10 was highly regulated in all studied passages. The present study demonstrated the immunological properties and multipotency of in vitro bAFMSCs collections, and thus, they can be tested in cattle pathological treatments or multiplication by nuclear transfer cloning.

2.
Pharmaceuticals (Basel) ; 16(12)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38139786

RESUMO

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.

3.
Molecules ; 28(22)2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-38005377

RESUMO

This review discusses the significance of natural deep eutectic solvents (NaDESs) as a promising green extraction technology. It employs the consolidated meta-analytic approach theory methodology, using the Web of Science and Scopus databases to analyze 2091 articles as the basis of the review. This review explores NaDESs by examining their properties, challenges, and limitations. It underscores the broad applications of NaDESs, some of which remain unexplored, with a focus on their roles as solvents and preservatives. NaDESs' connections with nanocarriers and their use in the food, cosmetics, and pharmaceutical sectors are highlighted. This article suggests that biomimicry could inspire researchers to develop technologies that are less harmful to the human body by emulating natural processes. This approach challenges the notion that green science is inferior. This review presents numerous successful studies and applications of NaDESs, concluding that they represent a viable and promising avenue for research in the field of green chemistry.

4.
Int Immunopharmacol ; 123: 110750, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37536181

RESUMO

Leishmaniasis, presenting the highest number of cases worldwide is one of the most serious Neglected Tropical Diseases (NTDs). Clinical manifestations are intrinsically related to the host's immune response making immunomodulatory substances the target of numerous studies on antileishmanial activity. The currently available drugs used for treatment present various problems including high toxicity, low efficacy, and associated drug resistance. The search for therapeutic alternatives is urgent, and in this context, thiophene derivatives appear to be a promising therapeutic alternative (many have shown promising anti-leishmanial activity). The objective of this study was to investigate the antileishmanial activity of the 2-amino-thiophenic derivative SB-200. The thiophenic derivative was effective in inhibiting the growth of Leishmania braziliensis, Leishmania major, and Leishmania infantum promastigotes, obtaining respective IC50 values of 4.25 µM, 4.65 µM, and 3.96 µM. For L. infantum, it was demonstrated that the antipromastigote effect of SB-200 is associated with cell membrane integrity losses, and with morphological changes observed during scanning and transmission electron microscopy. Cytotoxicity was performed for J774.A1 macrophages and VERO cells, to obtain a CC50 of 42.52 µM and a SI of 10.74 for macrophages and a CC50 of 39.2 µM and an SI of 9.89 for VERO cells. The anti-amastigote activity of SB-200 revealed an IC50 of 2.85 µM and an SI of 14.97 against macrophages and SI of 13.8 for VERO cells. The anti-amastigote activity of SB-200 is associated with in vitro immunomodulation. For acute toxicity, SB-200 against Zophobas morio larvae permitted 100% survival. We conclude that the 2-amino-thiophenic derivative SB-200 is a promising candidate for in vivo anti-leishmania drug tests to evaluate its activity, efficacy, and safety.


Assuntos
Antiprotozoários , Leishmania infantum , Leishmaniose , Animais , Chlorocebus aethiops , Camundongos , Células Vero , Tiofenos/farmacologia , Tiofenos/uso terapêutico , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Leishmaniose/tratamento farmacológico , Camundongos Endogâmicos BALB C
5.
Nanomedicine ; 51: 102689, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37156330

RESUMO

Alzheimer's disease (AD) is an illness that affects people aged 65 or older and affects around 6.5 million in the United States. Resveratrol is a chemical obtained from natural products and it exhibits biological activity based on inhibiting the formation, depolymerization of the amyloid, and decreasing neuroinflammation. Due to the insolubility of this compound; its incorporation in surfactant-based systems was proposed to design an intranasal formulation. A range of systems has been produced by mixing oleic acid, CETETH-20 and water. Polarised light microscopy (PLM), small angle x-ray scattering (SAXS) and transmission electron microscopy (TEM) confirm the initial liquid formulation (F) presented as microemulsion (ME). After dilution, the gelled systems were characterized as hexagonal mesophase and they showed feasibility proprieties. Pharmacological assays performed after intranasal administration showed the ability to improve learning and memory in animals, as well as remission of neuroinflammation via inhibition of interleukin.


Assuntos
Doença de Alzheimer , Cristais Líquidos , Animais , Administração Intranasal , Doença de Alzheimer/tratamento farmacológico , Resveratrol/farmacologia , Resveratrol/uso terapêutico , Espalhamento a Baixo Ângulo , Cristais Líquidos/química , Doenças Neuroinflamatórias , Difração de Raios X
6.
Biomolecules ; 13(3)2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36979510

RESUMO

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.


Assuntos
Anti-Infecciosos , Peptídeos Catiônicos Antimicrobianos , Animais , Camundongos , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Antimicrobianos , Células NIH 3T3 , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Anuros , Antibacterianos/farmacologia , Antibacterianos/análise , Testes de Sensibilidade Microbiana , Pele/química
7.
Molecules ; 28(3)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36770886

RESUMO

In recent years, lycopene has been highlighted due to its antioxidant and anti-inflammatory properties, associated with a beneficial effect on human health. The aim of this study was to advance the studies of antioxidant and anti-inflammatory mechanisms on human keratinocytes cells (HaCaT) of a self-emulsifying drug delivery system (SEDDS) loaded with lycopene purified from red guava (nanoLPG). The characteristics of nanoLPG were a hydrodynamic diameter of 205 nm, a polydispersity index of 0.21 and a zeta potential of -20.57, providing physical stability for the nanosystem. NanoLPG demonstrated antioxidant capacity, as shown using the ORAC methodology, and prevented DNA degradation (DNA agarose). Proinflammatory activity was evaluated by quantifying the cytokines TNF-α, IL-6 and IL-8, with only IL-8 showing a significant increase (p < 0.0001). NanoLPG showed greater inhibition of the tyrosinase and elastase enzymes, involved in the skin aging process, compared to purified lycopene (LPG). In vitro treatment for 24 h with 5.0 µg/mL of nanoLPG did not affect the viability of HaCaT cells. The ultrastructure of HaCaT cells demonstrated the maintenance of morphology. This contrasts with endoplasmic reticulum stresses and autophagic vacuoles when treated with LPG after stimulation or not with LPS. Therefore, the use of lycopene in a nanoemulsion may be beneficial in strategies and products associated with skin health.


Assuntos
Antioxidantes , Interleucina-8 , Humanos , Licopeno , Antioxidantes/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Anti-Inflamatórios/farmacologia , DNA
8.
Biopreserv Biobank ; 21(5): 504-509, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35904947

RESUMO

We isolated and further characterized fibroblasts obtained from postmortem skin biopsies of three different Brazilian wild species (Chrysocyon brachyurus-maned wolf, Cerdocyon thous-crab-eating fox, Mazama gouazoubira-brown brocket deer). The effects of two cryoprotectants, 10% dimethyl sulfoxide (DMSO) and 5% dimethylformamide (DMF), were assessed to determine the most efficient cryopreservation protocol. Such an investigation promotes the creation of germplasm banks, using samples that would otherwise be rejected and permanently lost following the death of the animals. We utilized animal corpses that were involved in highway accidents, found dead in the natural environment, or referred to us from the veterinary hospital at the Brasília Zoo. Fibroblasts from C. brachyurus specimens presented a delay in cell growth in Dulbecco's modified Eagle's medium in relation to other species. This observation is a limiting factor for the future storage of cells from this species. Differences in cellular morphology were observed between C. brachyurus, C. thous, and M. gouazoubira, presenting branched, fusiform, and spherical forms, respectively. The cryoprotective solution containing 10% DMSO was more efficient than 5% DMF medium in preserving the viability of fibroblasts of the three species (p < 0.05). After defining the best cryopreservation solution, a germplasm bank was successfully formed. This biological reservoir is configured as the first germplasm bank containing somatic cells and gametes of wild mammals of the Cerrado biome of Brazil. This material will be used for future characterization of the species and multiplication by means of nuclear transfer cloning.

9.
Nanomaterials (Basel) ; 12(20)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36296737

RESUMO

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.

11.
Front Cell Infect Microbiol ; 12: 920425, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35782121

RESUMO

Chikungunya virus (CHIKV) is a single-stranded positive RNA virus that belongs to the genus Alphavirus and is transmitted to humans by infected Aedes aegypti and Aedes albopictus bites. In humans, CHIKV usually causes painful symptoms during acute and chronic stages of infection. Conversely, virus-vector interaction does not disturb the mosquito's fitness, allowing a persistent infection. Herein, we studied CHIKV infection of Ae. aegypti Aag-2 cells (multiplicity of infection (MOI) of 0.1) for 48 h through label-free quantitative proteomic analysis and transmission electron microscopy (TEM). TEM images showed a high load of intracellular viral cargo at 48 h postinfection (hpi), as well as an unusual elongated mitochondria morphology that might indicate a mitochondrial imbalance. Proteome analysis revealed 196 regulated protein groups upon infection, which are related to protein synthesis, energy metabolism, signaling pathways, and apoptosis. These Aag-2 proteins regulated during CHIKV infection might have roles in antiviral and/or proviral mechanisms and the balance between viral propagation and the survival of host cells, possibly leading to the persistent infection.


Assuntos
Aedes , Febre de Chikungunya , Vírus Chikungunya , Animais , Humanos , Mosquitos Vetores , Proteoma , Proteômica
12.
Front Cell Infect Microbiol ; 12: 879018, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35755848

RESUMO

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.


Assuntos
Ascomicetos , Cromoblastomicose , Vesículas Extracelulares , Cromoblastomicose/microbiologia , Cromoblastomicose/patologia , Citocinas , Fonsecaea , Macrófagos , Óxido Nítrico , Virulência
13.
Talanta ; 243: 123355, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35272155

RESUMO

Mass testing for the diagnosis of COVID-19 has been hampered in many countries owing to the high cost of genetic material detection. This study reports on a low-cost immunoassay for detecting SARS-CoV-2 within 30 min using dynamic light scattering (DLS). The immunosensor comprises 50-nm gold nanoparticles (AuNPs) functionalized with antibodies against SARS-CoV-2 spike glycoprotein, whose bioconjugation was confirmed using transmission electron microscopy (TEM), UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), and surface-enhanced Raman scattering spectroscopy (SERS). The specific binding of the bioconjugates to the spike protein led to an increase in bioconjugate size, with a limit of detection (LOD) 5.29 × 103 TCID50/mL (Tissue Culture Infectious Dose). The immunosensor was also proven to be selective upon interaction with influenza viruses once no increase in size was observed after DLS measurement. The strategy proposed here aimed to use antibodies conjugated to AuNPs as a generic platform that can be extended to other detection principles, enabling technologies for low-cost mass testing for COVID-19.


Assuntos
Técnicas Biossensoriais , COVID-19 , Nanopartículas Metálicas , Técnicas Biossensoriais/métodos , COVID-19/diagnóstico , Teste para COVID-19 , Difusão Dinâmica da Luz , Ouro/química , Humanos , Imunoensaio/métodos , Nanopartículas Metálicas/química , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Proteínas Virais
14.
Sci Rep ; 12(1): 1361, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35079036

RESUMO

There is a consensus that arterial hypertension (AH) is associated with stroke. Therefore, this study aimed to evaluate the histology of the microvasculature associated with the mucosa of the posterior nasal cavity to identify possible factors related to vascular weakening and rupture. Histological sections were obtained from hypertensive and normotensive individuals, regardless of epistaxis. Our results showed that the group with AH had: (a) smaller median diameter of the lumen of arteries and arterioles; (b) increased thickness of the intimal arteries and arterioles, slight inflammatory infiltrate, and rupture of internal elastic lamina; (c) greater thickness of the middle tunica in arterioles; (d) lower percentage of histological sections with non-injured intimal layers in capillaries, arterioles, and small arteries; (e) lower percentage of histological sections with intact media tunic and/or myocytes juxtaposed in arteries and arterioles; (f) no difference between the diameters of small arteries or arterioles. The intima was thicker in individuals with severe epistaxis than in the normotensive group, but it did not differ from the AH group. Thus, hypertension may cause structural lesions in the vascular layers, and in the absence of tissue repair and the persistence of AH, these lesions may favour vascular rupture, especially during hypertensive peaks.


Assuntos
Pressão Sanguínea , Epistaxe , Hipertensão , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resistência Vascular
15.
Nanomedicine (Lond) ; 17(27): 2073-2088, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36853205

RESUMO

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.


Assuntos
Neoplasias da Mama , Nanopartículas , Humanos , Feminino , Linhagem Celular Tumoral , Distribuição Tecidual , Nanopartículas/química , Lipídeos , Neoplasias da Mama/diagnóstico por imagem , Emulsões/química
16.
Anim Biotechnol ; 33(6): 1014-1024, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33380273

RESUMO

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.


Assuntos
Células-Tronco Mesenquimais , Geleia de Wharton , Bovinos , Animais , Células Cultivadas , Geleia de Wharton/metabolismo , Transfecção , Adipócitos , Diferenciação Celular
17.
Oncotarget ; 12(19): 1920-1936, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34548908

RESUMO

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.

18.
Biopreserv Biobank ; 19(1): 11-18, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33035068

RESUMO

Preserving genetic material in cryogenic conditions presents a viable alternative for the protection of species' gene variability. However, there is an enormous need to establish and test cryopreservation protocols that are suitable for each diverse cell type to guarantee technical success in the long run. Considering this, fibroblasts from jaguar (Panthera onca), oncilla (Leopardus tigrinus), and pampas cat (Leopardus colocolo) were subjected to cell characterization and then cryopreservation in different cryoprotectant solutions (2.5%, 10% dimethyl sulfoxide [DMSO] or CryoSOfree™). Further testing was conducted to determine each solution's performance in preserving cell viability. In culture, a growth curve to assess cellular growth potential showed that exponential proliferation lasts for about the first 50 hours of in vitro culturing, declining in pace afterward. L. colocolo and L. tigrinus presented no difference in cell viability while using 2.5% DMSO protocols. P. onca cells did not present difference on viability for both concentrations of DMSO. Protocols using CryoSOfree resulted in a decreased viability of P. onca fibroblasts. Morphological differences between fibroblasts among the species were noted under bright field microscopy and scanning electron microscopy. L. colocolo and P. onca cells are fusiform, and L. tigrinus are spherical. All cells presented cytoplasmic projections. Transmission electron microscopy revealed vacuoles and secretion granules, indicating intense cell activity after thawing. Differences found in the efficiency of cryopreservation protocols according to the type of cryoprotectant indicate that species react differently to freezing and thawing processes. This research evaluates key aspects of in vitro protocols for cryopreservation of wild animals, which need to be optimized to guarantee successful cell culturing. More suitable protocols lead to increased efficiency in establishing fibroblast cryobanks and also facilitating the use of wild cats' cells in cloning techniques, contributing directly to preserving wild fauna.


Assuntos
Criopreservação , Animais , Brasil , Gatos , Crioprotetores , Dimetil Sulfóxido , Fibroblastos
19.
Cell Tissue Bank ; 22(2): 263-275, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33165826

RESUMO

To evaluate factors affecting corneal endothelial cell density (ECD) under enucleation and preservation time studies at Eye Bank of the Federal District of Brazil. We conducted a case-control study collecting data from 1128 corneas where death-to-enucleation time and enucleation-to-preservation time were within 24 h. Low cell count were those corneas with an ECD less than 2000 cells/mm2 and high cell count was defined as those with ECD greater than 2000 cells/mm2. We calculated the independent risk factors related to: cause of death, donor age, death-to-enucleation time, enucleation-to-preservation time and primary graft failure. Correlation analysis was used to assess which parameters influence ECD: death-to-enucleation time, enucleation-to-preservation time, average cell area (AVE), coefficient of variation and percentage of hexagonal cells. Of the total number of corneas, 1004 had ECD data and were selected for the study. 87.4% (n = 877) had high cell counts with 2699 ± 412 cells/mm2. The mean donor age was 38.8 ± 16 years. The most common causes of death were external causes (48.6%, n = 488). Longer times from death-to-enucleation, up to 24 h were not associated with a decrease in ECD (OR 0.58; P = 0.44) or risk of graft survival (P = 0.74). Enucleation-to-preservation intervals greater than 12 h showed increased risk of graft survival (P = 0.04). AVE was the main parameter for ECD (R2 = 0.96, P < 0.001). The overall graft survival rate was 98.2% (n = 761). Donors with 40 years of age and above did not present a higher risk of graft survival (P = 0.09). We suggest that the maximum time from death-to-enucleation should be 24 h, assuming the body has been refrigerated after 6 h; and from enucleation-to-preservation time of 12 h, followed by proper processing and cornea morphology examination.


Assuntos
Transplante de Córnea , Células Endoteliais , Endotélio Corneano , Adulto , Estudos de Casos e Controles , Contagem de Células , Córnea , Bancos de Olhos , Humanos , Pessoa de Meia-Idade , Preservação de Órgãos , Doadores de Tecidos , Adulto Jovem
20.
Front Cell Infect Microbiol ; 10: 573097, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33330123

RESUMO

Histoplasma capsulatum is a thermodimorphic fungus that causes histoplasmosis, a mycosis of global incidence. The disease is prevalent in temperate and tropical regions such as North America, South America, Europe, and Asia. It is known that during infection macrophages restrict Zn availability to H. capsulatum as a microbicidal mechanism. In this way the present work aimed to study the response of H. capsulatum to zinc deprivation. In silico analyses showed that H. capsulatum has eight genes related to zinc homeostasis ranging from transcription factors to CDF and ZIP family transporters. The transcriptional levels of ZAP1, ZRT1, and ZRT2 were induced under zinc-limiting conditions. The decrease in Zn availability increases fungicidal macrophage activity. Proteomics analysis during zinc deprivation at 24 and 48 h showed 265 proteins differentially expressed at 24 h and 68 at 48 h. Proteins related to energy production pathways, oxidative stress, and cell wall remodeling were regulated. The data also suggested that low metal availability increases the chitin and glycan content in fungal cell wall that results in smoother cell surface. Metal restriction also induces oxidative stress triggered, at least in part, by reduction in pyridoxin synthesis.


Assuntos
Histoplasma , Zinco , Ásia , Europa (Continente) , América do Norte
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