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1.
Bioinformatics ; 39(11)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37982752

RESUMO

MOTIVATION: The Oxford Nanopore technology has a great potential for the analysis of methylated motifs in genomes, including whole-genome methylome profiling. However, we found that there are no methylation motifs detection algorithms, which would be sensitive enough and return deterministic results. Thus, the MEME suit does not extract all Helicobacter pylori methylation sites de novo even using the iterative approach implemented in the most up-to-date methylation analysis tool Nanodisco. RESULTS: We present Snapper, a new highly sensitive approach, to extract methylation motif sequences based on a greedy motif selection algorithm. Snapper does not require manual control during the enrichment process and has enrichment sensitivity higher than MEME coupled with Tombo or Nanodisco instruments that was demonstrated on H.pylori strain J99 studied earlier by the PacBio technology and on four external datasets representing different bacterial species. We used Snapper to characterize the total methylome of a new H.pylori strain A45. At least four methylation sites that have not been described for H.pylori earlier were revealed. We experimentally confirmed the presence of a new CCAG-specific methyltransferase and inferred a gene encoding a new CCAAK-specific methyltransferase. AVAILABILITY AND IMPLEMENTATION: Snapper is implemented using Python and is freely available as a pip package named "snapper-ont." Also, Snapper and the demo dataset are available in Zenodo (10.5281/zenodo.10117651).


Assuntos
Genoma Bacteriano , Nanoporos , Metilação de DNA , Metiltransferases/genética , Metiltransferases/metabolismo , Algoritmos , Análise de Sequência de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala
2.
Int J Mol Sci ; 25(11)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38891883

RESUMO

Articular cartilage damage still remains a major problem in orthopedical surgery. The development of tissue engineering techniques such as autologous chondrocyte implantation is a promising way to improve clinical outcomes. On the other hand, the clinical application of autologous chondrocytes has considerable limitations. Mesenchymal stromal cells (MSCs) from various tissues have been shown to possess chondrogenic differentiation potential, although to different degrees. In the present study, we assessed the alterations in chondrogenesis-related gene transcription rates and extracellular matrix deposition levels before and after the chondrogenic differentiation of MSCs in a 3D spheroid culture. MSCs were obtained from three different tissues: umbilical cord Wharton's jelly (WJMSC-Wharton's jelly mesenchymal stromal cells), adipose tissue (ATMSC-adipose tissue mesenchymal stromal cells), and the dental pulp of deciduous teeth (SHEDs-stem cells from human exfoliated deciduous teeth). Monolayer MSC cultures served as baseline controls. Newly formed 3D spheroids composed of MSCs previously grown in 2D cultures were precultured for 2 days in growth medium, and then, chondrogenic differentiation was induced by maintaining them in the TGF-ß1-containing medium for 21 days. Among the MSC types studied, WJMSCs showed the most similarities with primary chondrocytes in terms of the upregulation of cartilage-specific gene expression. Interestingly, such upregulation occurred to some extent in all 3D spheroids, even prior to the addition of TGF-ß1. These results confirm that the potential of Wharton's jelly is on par with adipose tissue as a valuable cell source for cartilage engineering applications as well as for the treatment of osteoarthritis. The 3D spheroid environment on its own acts as a trigger for the chondrogenic differentiation of MSCs.


Assuntos
Diferenciação Celular , Condrócitos , Condrogênese , Matriz Extracelular , Células-Tronco Mesenquimais , Esferoides Celulares , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Humanos , Condrogênese/genética , Matriz Extracelular/metabolismo , Esferoides Celulares/citologia , Esferoides Celulares/metabolismo , Condrócitos/citologia , Condrócitos/metabolismo , Células Cultivadas , Geleia de Wharton/citologia , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Técnicas de Cultura de Células/métodos , Engenharia Tecidual/métodos , Cartilagem/citologia , Cartilagem/metabolismo , Dente Decíduo/citologia , Dente Decíduo/metabolismo , Polpa Dentária/citologia , Polpa Dentária/metabolismo
3.
MMWR Morb Mortal Wkly Rep ; 65(35): 930-3, 2016 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-27608169

RESUMO

Baylisascaris procyonis, predominantly found in raccoons, is a ubiquitous roundworm found throughout North America. Although raccoons are typically asymptomatic when infected with the parasite, the larval form of Baylisascaris procyonis can result in fatal human disease or severe neurologic outcomes if not treated rapidly. In the United States, Baylisascaris procyonis is more commonly enzootic in raccoons in the midwestern and northeastern regions and along the West Coast (1). However, since 2002, infections have been documented in other states (Florida and Georgia) and regions (2). Baylisascariasis is not a nationally notifiable disease in the United States, and little is known about how commonly it occurs or the range of clinical disease in humans. Case reports of seven human baylisascariasis cases in the United States diagnosed by Baylisascaris procyonis immunoblot testing at CDC are described, including review of clinical history and laboratory data. Although all seven patients survived, approximately half were left with severe neurologic deficits. Prevention through close monitoring of children at play, frequent handwashing, and clearing of raccoon latrines (communal sites where raccoons defecate) are critical interventions in curbing Baylisascaris infections. Early treatment of suspected cases is critical to prevent permanent sequelae.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridoidea/isolamento & purificação , Doenças do Sistema Nervoso Central/diagnóstico , Oftalmopatias/diagnóstico , Guaxinins/parasitologia , Adulto , Animais , Infecções por Ascaridida/transmissão , Doenças do Sistema Nervoso Central/parasitologia , Criança , Oftalmopatias/parasitologia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estados Unidos
4.
Biomimetics (Basel) ; 9(7)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39056846

RESUMO

The umbilical cord is a material that enhances regeneration and is devoid of age-related changes in the extracellular matrix (ECM). The aim of this work was to develop a biodegradable scaffold from a decellularized human umbilical cord (UC-scaffold) to heal full-thickness wounds. Decellularization was performed with 0.05% sodium dodecyl sulfate solution. The UC-scaffold was studied using morphological analysis methods. The composition of the UC-scaffold was studied using immunoblotting and Fourier transform infrared spectroscopy. The adhesion and proliferation of mesenchymal stromal cells were investigated using the LIVE/DEAD assay. The local reaction was determined by subcutaneous implantation in mice (n = 60). A model of a full-thickness skin wound in mice (n = 64) was used to assess the biological activity of the UC-scaffold. The proposed decellularization method showed its effectiveness in the umbilical cord, as it removed cells and retained a porous structure, type I and type IV collagen, TGF-ß3, VEGF, and fibronectin in the ECM. The biodegradation of the UC-scaffold in the presence of collagenase, its stability during incubation in hyaluronidase solution, and its ability to swell by 1617 ± 120% were demonstrated. Subcutaneous scaffold implantation in mice showed gradual resorption of the product in vivo without the formation of a dense connective tissue capsule. Epithelialization of the wound occurred completely in contrast to the controls. All of these data suggest a potential for the use of the UC-scaffold.

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