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1.
An Acad Bras Cienc ; 95(2): e20201622, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37341265

RESUMO

The golden mussel (Limnoperna fortunei) is an aggressive invasive species in South America, where it endangers native species and freshwater ecosystems, in addition to causing extensive economic losses, mainly to the hydroelectric sector. Currently, there's no efficient control method available and the invasion has progressed across the continent. Its high reproduction rate is one of the key factors of the golden mussel's high invasive potential and, recently, efforts have been done in order to understand the reproduction and the sexual features of this species. However, its cytogenetics characterization is incipient and the possible occurrence of sex-specific cytogenetic features was never investigated. In this study, we aimed to characterize the chromosomal morphometry, the distribution profile of heterochromatin, and to detect possible sex-related epigenetic marks in the golden mussel. Results revealed that the karyotypic structure is similar in both sexes and no chromosome heteromorphism was observed between males and females specimens. The data increment the cytogenetic characterization of Limnoperna fortunei and contribute for future studies that aim to further investigate its reproduction and underlying sex determination processes.


Assuntos
Ecossistema , Mytilidae , Feminino , Masculino , Animais , Mytilidae/genética , Citogenética , Cromossomos Sexuais/genética , Cariotipagem
2.
Gigascience ; 122022 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-37776366

RESUMO

BACKGROUND: The golden mussel (Limnoperna fortunei) is a highly invasive species that causes environmental and socioeconomic losses in invaded areas. Reference genomes have proven to be a valuable resource for studying the biology of invasive species. While the current golden mussel genome has been useful for identifying new genes, its high fragmentation hinders some applications. FINDINGS: In this study, we provide the first chromosome-level reference genome for the golden mussel. The genome was built using PacBio HiFi, 10X, and Hi-C sequencing data. The final assembly contains 99.4% of its total length assembled to the 15 chromosomes of the species and a scaffold N50 of 97.05 Mb. A total of 34,862 protein-coding genes were predicted, of which 84.7% were functionally annotated. A significant (6.48%) proportion of the genome was found to be in a hemizygous state. Using the new genome, we have performed a genome-wide characterization of the Doublesex and Mab-3 related transcription factor gene family, which has been proposed as a target for population control strategies in other species. CONCLUSIONS: From the applied research perspective, a higher-quality genome will support genome editing with the aim of developing biotechnology-based solutions to control invasion. From the basic research perspective, the new genome is a high-quality reference for molecular evolutionary studies of Mytilida and other Lophotrochozoa, and it may be used as a reference for future resequencing studies to assess genomic variation among different golden mussel populations, unveiling potential routes of dispersion and helping to establish better control policies.


Assuntos
Mytilidae , Animais , Mytilidae/genética , Genoma , Cromossomos/genética
3.
Biologicals ; 66: 9-16, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32561214

RESUMO

Bone tissue-derive biomaterials have become of great interest to treat diseases of the skeletal system. Biological scaffolds of demineralized and decellularized extracellular matrices (ECM) have been developed and one of these options are ECM hydrogels derived from bovine bone. Nanomaterials may be able to regulate stem cell differentiation due to their unique physical-chemical properties. The present work aimed to evaluate the osteoinductive effects of ECM hydrogels associated with barium titanate nanoparticles (BTNP) on dental pulp cells derived from exfoliated teeth. The addition of BTNP in the ECM derived hydrogel did not affect cell proliferation and the formation of bone nodules. Furthermore, it increased the expression of bone alkaline phosphatase. The results demonstrated that the nanobiocomposites were able to promote the osteogenic differentiation, even in the absence of chemical inducing factors for osteogenic differentiation. In conclusion, bovine bone ECM hydrogel combined with BTNP presented and increased expression of markers of osteogenic differentiation in the absence of chemical inducing factors.


Assuntos
Compostos de Bário/farmacologia , Proliferação de Células/efeitos dos fármacos , Matriz Extracelular , Hidrogéis/farmacologia , Osteogênese/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Titânio/farmacologia , Fosfatase Alcalina/efeitos dos fármacos , Fosfatase Alcalina/genética , Animais , Técnica de Desmineralização Óssea , Proteína Morfogenética Óssea 2/efeitos dos fármacos , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 4/efeitos dos fármacos , Proteína Morfogenética Óssea 4/genética , Bovinos , Polpa Dentária/citologia , Glicosaminoglicanos/metabolismo , Humanos , Nanopartículas Metálicas , Microscopia Eletrônica de Varredura , Osteogênese/genética , Reologia , Análise Espectral Raman , Células-Tronco/metabolismo , Células-Tronco/ultraestrutura , Engenharia Tecidual/métodos , Alicerces Teciduais
4.
Biomed Mater ; 14(3): 035011, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30802890

RESUMO

Nanomaterials can mimic properties of extracellular matrix molecules, promising great potential for scaffold composition in tissue engineering. In the present study, we investigated whether barium titanate nanoparticles (BT NP) combined with alginate polymer would provide a new cytocompatible three-dimensional (3D) scaffold to induce osteogenic stem cell differentiation. In vitro cytocompatibility and osteogenic differentiation potential were investigated using human mesenchymal stem cells (MSC). Firstly, we studied the cell viability and oxidative stress by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) thiazolyl blue tetrazolium bromide (MTT) and superoxide dismutase (SOD) assays. Overall, neither pure BT NP or BT NP/alginate 3D scaffold induced cytotoxicity. The scanning electron and atomic force microscopy revealed that BT NP/alginate 3D scaffold produced exhibited highly interconnected pores and surface nanotopography that were favorable for MSC differentiation. Von Kossa staining showed mineralization nodules and MSCs morphology changed from spindle to cuboid shape after 21 d. Finally, BMP-2 and ALP mRNA were significantly upregulated on cells grown into the BT NP/alginate 3D scaffold. Thus, the BT NP/alginate 3D scaffold showed an osteogenic differentiation induction potential, without the addition of osteogenic supplements. These results indicate that the BT NP/alginate 3D scaffold provides a cytocompatible and bioactive microenvironment for osteogenic human MSC differentiation.


Assuntos
Alginatos/química , Compostos de Bário/química , Nanopartículas Metálicas/química , Células-Tronco/citologia , Alicerces Teciduais/química , Titânio/química , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Microscopia Eletrônica de Varredura , Osteogênese , Estresse Oxidativo , Polímeros/química , Análise Espectral Raman , Engenharia Tecidual/métodos
5.
An Bras Dermatol ; 92(5): 717-720, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29166516

RESUMO

Proteus syndrome is a rare syndrome characterized by disproportionate overgrowth of limbs, multiple hamartomas, and vascular malformations. The cerebriform connective tissue nevi, also called cerebriform plantar hyperplasia, are present in most patients, and is the main characteristic of the syndrome. If present, even alone, they can be considered as a pathognomonic sign. This article reports a classic case of Proteus syndrome in a 2-year-old male patient who began to show a discrete asymmetry of the right hemibody in relation to the left one after birth, which increased over the months. He also showed cerebriform plantar hyperplasia and Port-wine stains, among other alterations.


Assuntos
Síndrome de Proteu/diagnóstico , Pré-Escolar , Humanos , Masculino , Fotografação
6.
An. bras. dermatol ; 92(5): 717-720, Sept.-Oct. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-887020

RESUMO

Abstract: Proteus syndrome is a rare syndrome characterized by disproportionate overgrowth of limbs, multiple hamartomas, and vascular malformations. The cerebriform connective tissue nevi, also called cerebriform plantar hyperplasia, are present in most patients, and is the main characteristic of the syndrome. If present, even alone, they can be considered as a pathognomonic sign. This article reports a classic case of Proteus syndrome in a 2-year-old male patient who began to show a discrete asymmetry of the right hemibody in relation to the left one after birth, which increased over the months. He also showed cerebriform plantar hyperplasia and Port-wine stains, among other alterations.


Assuntos
Humanos , Masculino , Pré-Escolar , Síndrome de Proteu/diagnóstico , Fotografação
7.
An. bras. dermatol ; 91(5,supl.1): 29-31, Sept.-Oct. 2016. graf
Artigo em Inglês | LILACS | ID: biblio-837926

RESUMO

Abstract Cryptococcosis is a fungal infection caused by Cryptococcus neoformans that tends to affect immunocompromised individuals. The fungi are mostly acquired by inhalation, which leads to an initial pulmonary infection. Later, other organs - such as the central nervous system and the skin - can be affected by hematogenous spread. In addition, cutaneous contamination can occur by primary inoculation after injuries (primary cutaneous cryptococcosis), whose diagnosis is defined based on the absence of systemic involvement. The clinical presentation of cutaneous forms typically vary according to the infection mode. We report an unusual case of disseminated cryptococcosis in an immunocompetent patient with cutaneous lesions similar to those caused by primary inoculation. This clinical picture leads us to question the definition of primary cutaneous cryptococcosis established in the literature.


Assuntos
Humanos , Masculino , Idoso , Hospedeiro Imunocomprometido , Criptococose/patologia , Dermatomicoses/patologia , Pele/microbiologia , Pele/patologia , Biópsia , Infecções Oportunistas/microbiologia , Criptococose/imunologia , Criptococose/microbiologia , Cryptococcus neoformans/isolamento & purificação , Dermatomicoses/imunologia , Dermatomicoses/microbiologia
8.
An Bras Dermatol ; 91(5 suppl 1): 29-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28300886

RESUMO

Cryptococcosis is a fungal infection caused by Cryptococcus neoformans that tends to affect immunocompromised individuals. The fungi are mostly acquired by inhalation, which leads to an initial pulmonary infection. Later, other organs - such as the central nervous system and the skin - can be affected by hematogenous spread. In addition, cutaneous contamination can occur by primary inoculation after injuries (primary cutaneous cryptococcosis), whose diagnosis is defined based on the absence of systemic involvement. The clinical presentation of cutaneous forms typically vary according to the infection mode. We report an unusual case of disseminated cryptococcosis in an immunocompetent patient with cutaneous lesions similar to those caused by primary inoculation. This clinical picture leads us to question the definition of primary cutaneous cryptococcosis established in the literature.


Assuntos
Criptococose/patologia , Dermatomicoses/patologia , Hospedeiro Imunocomprometido , Idoso , Biópsia , Criptococose/imunologia , Criptococose/microbiologia , Cryptococcus neoformans/isolamento & purificação , Dermatomicoses/imunologia , Dermatomicoses/microbiologia , Humanos , Masculino , Infecções Oportunistas/microbiologia , Pele/microbiologia , Pele/patologia
9.
Chronobiol Int ; 33(1): 108-16, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26654732

RESUMO

Studies have shown a relationship between circadian rhythm disruptions and type-2 diabetes. This investigation examined the effects of circadian disruption (6-h phase advances) on the progression of diabetes in a type-2 diabetic mouse model -TALLYHO/JngJ - and whether wheel-running can alleviate the effects of the phase advances. 6-h advances alter fasting glucose, glucose tolerance and insulin production. Wheel-running reduced body mass, improved glucose tolerance and reduced insulin in TALLYHO/JngJ and alleviated some of the changes in diabetic symptoms due to 6-h advances. These results indicate that individuals with type-2 diabetes can benefit from physical activity and exercise can be a countermeasure to offset the effects of an acute phase advance.


Assuntos
Glicemia/análise , Ritmo Circadiano/fisiologia , Diabetes Mellitus Tipo 2/metabolismo , Jejum/fisiologia , Insulina/biossíntese , Atividade Motora/fisiologia , Corrida/fisiologia , Animais , Modelos Animais de Doenças , Masculino , Condicionamento Físico Animal , Fatores de Tempo
10.
Alcohol ; 49(4): 367-76, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25850902

RESUMO

Bipolar patients have a high prevalence of comorbid alcohol use and abuse disorders, while chronic alcohol drinking may increase the presence and severity of certain symptoms of bipolar disorder. As such, there may be many individuals that are prescribed lithium to alleviate the manic symptoms of bipolar disorder, but also drink alcohol concurrently. In addition, both alcoholics and individuals with bipolar disorder often exhibit disruptions to their sleep-wake cycles and other circadian rhythms. Interestingly, both ethanol and lithium are known to alter both the period and the phase of free-running rhythms in mammals. While lithium is known to lengthen the period, ethanol seems to shorten the period and attenuate the responses to acute light pulses. Therefore, the present study aimed to determine whether ethanol and lithium have opposing effects on the circadian pacemaker when administered together. C57BL/6J mice were provided drinking solutions containing lithium, alcohol, or both, and their free-running rhythms along with their response to photic phase shifts were investigated. Mice treated with lithium displayed period lengthening, which was almost completely negated when ethanol was added. Moreover, ethanol significantly attenuated light-induced phase delays while the addition of lithium partially restored this response. These results indicate that alcohol and lithium have opposing effects on behavioral circadian rhythms. Individuals with bipolar disorder who are prescribed lithium and who drink alcohol might be inadvertently altering their sleep and circadian cycles, which may exacerbate their symptoms.


Assuntos
Antimaníacos/farmacologia , Comportamento Animal/efeitos dos fármacos , Depressores do Sistema Nervoso Central/farmacologia , Ritmo Circadiano/efeitos dos fármacos , Etanol/farmacologia , Cloreto de Lítio/farmacologia , Atividade Motora/efeitos dos fármacos , Animais , Luz , Masculino , Camundongos , Camundongos Endogâmicos C57BL
11.
Stem Cells Int ; 2015: 487467, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25763072

RESUMO

The satellite cells are long regarded as heterogeneous cell population, which is intimately linked to the processes of muscular recovery. The heterogeneous cell population may be classified by specific markers. In spite of the significant amount of variation amongst the satellite cell populations, it seems that their activity is tightly bound to the paired box 7 transcription factor expression, which is, therefore, used as a canonical marker for these cells. Muscular dystrophic diseases, such as Duchenne muscular dystrophy, elicit severe tissue injuries leading those patients to display a very specific pattern of muscular recovery abnormalities. There have been works on the application of precursors cells as a therapeutic alternative for Duchenne muscular dystrophy and initial attempts have proven the cells inefficient; however later endeavours have proposed solutions for the experiments improving significantly the results. The presence of a range of satellite cells populations indicates the existence of specific cells with enhanced capability of muscular recovery in afflicted muscles.

12.
World J Stem Cells ; 7(1): 106-15, 2015 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-25621110

RESUMO

Despite the advances in the hematology field, blood transfusion-related iatrogenesis is still a major issue to be considered during such procedures due to blood antigenic incompatibility. This places pluripotent stem cells as a possible ally in the production of more suitable blood products. The present review article aims to provide a comprehensive summary of the state-of-the-art concerning the differentiation of both embryonic stem cells and induced pluripotent stem cells to hematopoietic cell lines. Here, we review the most recently published protocols to achieve the production of blood cells for future application in hemotherapy, cancer therapy and basic research.

13.
Rev. Soc. Bras. Clín. Méd ; 7(6)nov.-dez. 2009.
Artigo em Português | LILACS | ID: lil-533124

RESUMO

JUSTIFICATIVA E OBJETIVOS: A síndrome de Cogan caracteriza-se pela presença de ceratite não luética associada à disfunção cócleo-vestibular. Pode ter várias outras manifestações clínicas, como: mialgia, febre e vasculite. Menos de 300 casos foram relatados até fevereiro do corrente ano e nenhum publicado na literatura mundial, apresentando positividade do marcador c-ANCA associado à antiproteinase PR3. O objetivo do presente estudo foi alertar os colegas médicos sobre essa entidade nosológica pouco conhecida, que exige um tratamento precoce imunossupressor, com a finalidade de melhorar o prognóstico. RELATO DO CASO: Paciente do sexo masculino, 43 anos, branco, casado, comerciário, natural de Piratini (RS) e procedente de sua residência, após ter ficado hospitalizado por 10 dias e recebido alta sem diagnóstico. Destaca-se descrição de síndrome clínica rara iniciada por comprometimento ocular (olho vermelho), mialgias, febre e, 30 dias após, quadro sugestivo de comprometimento do oitavo par craniano, de aparecimento súbito, caracterizado por nistagmo, náuseas, vômitos e ataxia para a marcha. Durante a internação, associou-se o aparecimento de sufusões subungueais dolorosas compatíveis com vasculite sistêmica. CONCLUSÃO: O estudo do diagnóstico diferencial sobre vasculites auxiliou decisivamente a conclusão diagnóstica final; inclusive a resposta terapêutica com pulsoterapia (metilprednisolona 1g, por via venosa durante quatro dias) foi eficaz. Os sinais e os sintomas desapareceram em 24h.


Assuntos
Humanos , Masculino , Adulto , Ceratite/diagnóstico , Surdez , Perda Auditiva/diagnóstico , Síndrome , Neuronite Vestibular , Vasculite/diagnóstico
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