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1.
Anat Histol Embryol ; 53(4): e13062, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38837469

RESUMO

Although the order Rodentia does not present a high risk of extinction compared to mammals as a whole, several families demonstrate high levels of threat and/or data deficiency, therefore highlighting the need for targeted research and the application of ecological and reproductive data to the development of conservation actions. The order Rodentia, the largest among mammals, includes 9 families, and the family Cricetidae is the most diverse of the Brazilian rodents. In Brazil, 12 of the 16 genera of Oecomys are found. Oecomys bicolor is known in Brazil as the 'arboreal rat' and is, found in dry, deciduous and tropical forests. The mean body weight of Oecomys bicolor was 35.8 g and the gonadal, tubular and epithelial somatic indexes were, 0.53%, 0.47% and 0.37%, respectively. Seminiferous tubules volume density was 89.72% and the mitotic and meiotic indexes corresponded to 8.59 and 2.45 cells, respectively, and the yield of spermatogenesis was 23.83 cells. The intertubular compartment represented 10.28% of the testis parenchyma and around 5% of the interstitial space was occupied by Leydig cells, whose number per gram of testis was 11.10 × 107 cells. By evaluating the biometric and histomorphometric characteristics of the testis, there is evidence that this species has a high investment in reproduction. Due to the high contribution of the seminiferous epithelium and the intertubular compartment in this species, compared to the others of the same family, it is possible to infer that the species Oecomys bicolor has a promiscuous reproductive behaviour.


Assuntos
Arvicolinae , Células Intersticiais do Testículo , Espermatogênese , Testículo , Animais , Espermatogênese/fisiologia , Masculino , Testículo/anatomia & histologia , Testículo/fisiologia , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/fisiologia , Arvicolinae/anatomia & histologia , Arvicolinae/fisiologia , Túbulos Seminíferos/anatomia & histologia , Brasil
2.
Photochem Photobiol ; 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37909171

RESUMO

Natural products derived from plants can be used as photosensitizers for antimicrobial photodynamic therapy (aPDT) combining key therapeutic strategies for tissue repair while controlling microorganisms' growth. We investigated a standardized extract of pequi peels (Caryocar brasiliense Cambess) as a brownish natural photosensitizer for aPDT using blue light. Three concentrations of the pequi extract (PE; 10, 30, or 90 µg/mL) were tested solely or associated with blue laser (445 nm, 100 mW, 138 J/cm2 , 6 J, 60 s). In vitro, we quantified reactive oxygen species (ROS), assessed skin keratinocytes (HaCat) viability and migration, and aPDT antimicrobial activity on Streptococcus or Staphylococcus strains. In vivo, we assessed wound closure for the most active concentration disclosed by the in vitro assay (30 µg/mL). Upon aPDT treatments, ROS were significantly increased in cell monolayers regardless of PE concentration. PE at low doses stimulates epithelial cells. Although PE stimulated cellular migration, aPDT was moderately cytotoxic to skin keratinocytes, particularly at the highest concentration. The antimicrobial activity was observed for PE at the lowest concentration (10 µg/mL) and mostly at PE 10 µg/mL and 30 µg/mL when used as aPDT photosensitizers. aPDT with PE 30 µg/mL presents antimicrobial activity without compromising the initial phases of skin repair.

3.
J Oral Pathol Med ; 51(2): 206-216, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35048460

RESUMO

BACKGROUND: Central giant cell granulomas (CGCG) of the jaws are osteolytic lesions that may behave aggressively and respond poorly to surgery. Microscopically, in addition to giant cells, there is a mononuclear cell population composed of macrophage/monocytic cells and spindle-shaped cells of mesenchymal origin. Seventy two percent of these tumours harbour mutually exclusive TRPV4, KRAS and FGFR1 mutations. We aimed to assess the mutational status of mononuclear and giant cells and the osteogenic potential of stromal cells in vitro and in vivo. METHODS AND RESULTS: We screened CGCG for signature mutations and used laser-capture microdissection to demonstrate that the mutations are restricted to the mononuclear cells. Additionally, we established CGCG primary cell culture and observed that the cells retained the mutations throughout passages. By flow cytometry, we observed predominance of CD14- CD51- CD61- cells, consistent with the expected profile for stromal cells. Considering the mesenchymal origin of stromal cells, we assessed the osteogenic differentiation potential of CGCG cells in culture by cytochemistry (von Kossa and alizarin red staining), alkaline phosphatase (ALP) activity assay and gene expression of osteogenic markers. CGCG cells presented self-capacity to increase ALP levels in a time-dependent manner and under osteogenic induction presented increasing number of calcium deposits, and overall higher expression of osteocalcin, RUNX2, ALPL and osteopontin than cells without osteogenic induction. A patient-derived xenograft model for CGCG was established, and osteoid material deposition was observed. CONCLUSION: Collectively, the results confirm that the signature mutations are restricted to stromal cells in CGCG, and the in vitro and in vivo results support that these cells have the capacity to differentiate into osteoblasts, in line with the bone formation often observed in the stroma of these lesions.


Assuntos
Granuloma de Células Gigantes , Células-Tronco Mesenquimais , Fosfatase Alcalina , Diferenciação Celular , Células Cultivadas , Granuloma de Células Gigantes/genética , Humanos , Arcada Osseodentária , Mutação , Osteogênese/genética , Células Estromais
5.
Mater Sci Eng C Mater Biol Appl ; 118: 111322, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33254960

RESUMO

In this study we prepared annatto-loaded cellulose acetate nanofiber scaffolds and evaluated both in vitro cytotoxicity and potential for wound healing in a rat model. Annatto extract, which has been used to accelerate wound healing, was added to cellulose acetate polymer and the resulting material was used to produce nanofiber scaffolds via electrospinning. Physicochemical, and thermal evaluation of the resulting nanofiber mats showed that incorporating annatto did not significantly affect the thermal or chemical stability of the polymer. Annatto extract did not demonstrate cytotoxicity in the HET-CAM assay or MTT assay for fibroblast culture. Scanning electron microscopy of the fibroblasts confirmed that cells spread and penetrated into the nanofiber. In vivo experiments confirmed that cellulose acetate retained its biocompatibility when associated with crude annatto extract, and suggested that dose/response modulation occurs between the annatto-functionalized nanofibers and mast cells, indicating the potential of this material for wound healing applications.


Assuntos
Nanofibras , Animais , Bixaceae , Carotenoides , Celulose/análogos & derivados , Extratos Vegetais/farmacologia , Ratos , Cicatrização
6.
Cell Tissue Res ; 382(2): 391-404, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32666138

RESUMO

Mice are widely used as experimental models due to several positive characteristics and in particular their suitability for studies involving molecular biology and transgenesis. Despite the large number of mice strains currently available, the literature regarding their basic reproductive biology is still relatively scarce. Herein, we comparatively evaluated several important and correlated parameters related to testis structure and function in sexually mature male mice of inbred (C57BL/6, n = 19; BALB/c, n = 17) and outbred (Swiss, n = 17) strains, frequently utilized in research. Swiss mice presented significant variation for many parameters evaluated, including higher sperm production, mainly when compared to the C57BL/6 strain. However, some key parameters such as the duration of spermatogenesis, the Sertoli cell number per testis, and the spermatogenic efficiency were similar among the different strains. Although presenting significantly higher Leydig cell (LC) proportion and numbers per testis gram and per testis, the anogenital index was smaller in Swiss mice. Estradiol levels were lower in C57BL/6, whereas testosterone levels and 3ß-HSD expression were similar among strains. Regarding the LC/macrophages relationship, in comparison to the literature, we reported a much higher contribution of macrophages to the mouse intertubule. Thus, we estimated that there are around 1.6 macrophages per LC in BALB/c mice and this intriguing finding could be relevant to testis function in overall and spermatogonial biology in particular. Taken together, our results highlight the importance of knowing more accurately the testis structure and function in the different mice strains available for research, particularly when a specific testis parameter is being investigated.


Assuntos
Testículo/anatomia & histologia , Testículo/fisiologia , Animais , Masculino , Camundongos
7.
Clin Oral Investig ; 24(7): 2451-2458, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31713744

RESUMO

OBJECTIVE: Odontogenic myxoma (OM) occasionally responds poorly to surgical treatment. The MAPK pathway is constitutively activated in several neoplasms and we aimed to test if the MAPK pathway is activated in OM, in order to pave the way for an alternative therapy for aggressive and recurrent cases. MATERIALS AND METHODS: The immunoexpression of phosphorylated ERK1/2 (pERK1/2) was assessed in OM. We established a 3D organotypic culture model for the in vitro study and patient-derived xenografts (PDX) in mice for the in vivo study. The MEK inhibitor U0126 was used to inhibit phosphorylation of ERK1/2 in the in vitro and in vivo models. RESULTS: All OM showed strong pERK1/2 immunoexpression, consistent with MAPK pathway activation. Treatment of the 3D culture with U0126 resulted in a reduced pERK1/2/ERK1/2 ratio. Consistent with the in vitro results, all PDX of animals treated with U0126 showed a decreased volume fold change compared with controls. CONCLUSIONS: The MAPK pathway is activated in OM and its inhibition leads to tumor shrinkage in PDX and cell culture models. CLINICAL RELEVANCE: Our results offer a pre-clinical frame for OM-targeted therapy. Further work is needed to determine if this initial finding holds clinical promise.


Assuntos
Doenças da Boca , Mixoma , Animais , Fosfatase 1 de Especificidade Dupla/efeitos dos fármacos , Humanos , Camundongos , Doenças da Boca/tratamento farmacológico , Mixoma/tratamento farmacológico , Fosforilação
8.
Life Sci ; 232: 116629, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31276687

RESUMO

AIMS: To investigate the effects of moderate aerobic physical training on cardiac function and morphology as well as on the levels of glial cell-derived neurotrophic factor (GDNF), nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF) of animals infected with the Y strain of Trypanosoma cruzi. MAIN METHODS: Twenty-eight male C57BL/6 mice were distributed into 4 groups: sedentary control (SC), trained control (TC), sedentary infected (CHC) and trained infected (CHT). The infection was performed by intraperitoneal injection of trypomastigote forms and the animals were adapted to treadmill in the week before the beginning of the training protocol, initiated 45 days post infection. Maximal exercise test (TEM) was performed at the baseline as well as at the end of the 4th, 8th and 12th weeks of training. At the end of the 12th week, all animals were evaluated for cardiac morphology and function by echocardiography. KEY FINDINGS: CHC group showed a larger area of right ventricle (RVA), increased end-systolic volume and reduction in ejection fraction (EF), stroke volume (SV), cardiac output (CO) and fractional area change (FAC). The training reduced the RVA and improved the FAC of chagasic animals. GDNF level was higher in TC and CHC groups compared to SC in heart and BDNF levels were higher in CHC compared to SC in heart and serum. SIGNIFICANCE: Physical training ameliorated the cardiac function of infected animals and promoted adjusts in BDNF and GDNF levels. These findings evidenced these neurotrophins as possible biomarkers of cardiac function responsive to exercise stimulus.


Assuntos
Tolerância ao Exercício/fisiologia , Condicionamento Físico Animal/métodos , Condicionamento Físico Animal/fisiologia , Animais , Biomarcadores/sangue , Fator Neurotrófico Derivado do Encéfalo/análise , Fator Neurotrófico Derivado do Encéfalo/fisiologia , Débito Cardíaco , Doença de Chagas/metabolismo , Modelos Animais de Doenças , Ecocardiografia , Teste de Esforço , Fator Neurotrófico Derivado de Linhagem de Célula Glial/análise , Fator Neurotrófico Derivado de Linhagem de Célula Glial/fisiologia , Coração/fisiologia , Testes de Função Cardíaca , Ventrículos do Coração/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator de Crescimento Neural/análise , Fator de Crescimento Neural/fisiologia , Fatores de Crescimento Neural/metabolismo , Fatores de Crescimento Neural/fisiologia , Volume Sistólico/fisiologia , Trypanosoma cruzi/patogenicidade
9.
Methods Mol Biol ; 1035: 35-42, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23959980

RESUMO

Morphometry is a classical quantitative method often used in biology to provide a data basis for functional interpretations/interactions of a particular organ or system. Herein we took advantage of this valuable approach to evaluate the spermatogonial stem cell niche using the horse testis and immunocytochemical localization of GFRA1 [glial cell line-derived neurotrophic factor receptor produced by Sertoli cells)] as an example. Using the NIH ImageJ free software, we describe in detail all the necessary steps to investigate this specific and crucial microenvironment. Based on several recently published papers from our research group, this approach has proved to be fast, simple, and adaptable to a wide range of species and has the potential to be easily reproducible in different laboratories.


Assuntos
Células-Tronco Adultas/metabolismo , Software , Nicho de Células-Tronco , Animais , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Cavalos , Imuno-Histoquímica , Masculino , Camundongos , Túbulos Seminíferos/citologia , Espermatogênese
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