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1.
Nat Commun ; 15(1): 1761, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409161

RESUMO

Tissue damage elicits cell fate switching through a process called metaplasia, but how the starting cell fate is silenced and the new cell fate is activated has not been investigated in animals. In cell culture, pioneer transcription factors mediate "reprogramming" by opening new chromatin sites for expression that can attract transcription factors from the starting cell's enhancers. Here we report that SOX4 is sufficient to initiate hepatobiliary metaplasia in the adult mouse liver, closely mimicking metaplasia initiated by toxic damage to the liver. In lineage-traced cells, we assessed the timing of SOX4-mediated opening of enhancer chromatin versus enhancer decommissioning. Initially, SOX4 directly binds to and closes hepatocyte regulatory sequences via an overlapping motif with HNF4A, a hepatocyte master regulatory transcription factor. Subsequently, SOX4 exerts pioneer factor activity to open biliary regulatory sequences. The results delineate a hierarchy by which gene networks become reprogrammed under physiological conditions, providing deeper insight into the basis for cell fate transitions in animals.


Assuntos
Reprogramação Celular , Cromatina , Animais , Camundongos , Diferenciação Celular/genética , Reprogramação Celular/genética , Metaplasia , Fatores de Transcrição/metabolismo
2.
bioRxiv ; 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36824858

RESUMO

Tissue damage elicits cell fate switching through a process called metaplasia, but how the starting cell fate is silenced and the new cell fate is activated has not been investigated in animals. In cell culture, pioneer transcription factors mediate "reprogramming" by opening new chromatin sites for expression that can attract transcription factors from the starting cell's enhancers. Here we report that Sox4 is sufficient to initiate hepatobiliary metaplasia in the adult liver. In lineage-traced cells, we assessed the timing of Sox4-mediated opening of enhancer chromatin versus enhancer decommissioning. Initially, Sox4 directly binds to and closes hepatocyte regulatory sequences via a motif it overlaps with Hnf4a, a hepatocyte master regulator. Subsequently, Sox4 exerts pioneer factor activity to open biliary regulatory sequences. The results delineate a hierarchy by which gene networks become reprogrammed under physiological conditions, providing deeper insight into the basis for cell fate transitions in animals.

3.
Hepatology ; 78(2): 486-502, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36037289

RESUMO

BACKGROUND AND AIMS: Assessing mammalian gene function in vivo has traditionally relied on manipulation of the mouse genome in embryonic stem cells or perizygotic embryos. These approaches are time-consuming and require extensive breeding when simultaneous mutations in multiple genes is desired. The aim of this study is to introduce a rapid in vivo multiplexed editing (RIME) method and provide proof of concept of this system. APPROACH AND RESULTS: RIME, a system wherein CRISPR/caspase 9 technology, paired with adeno-associated viruses (AAVs), permits the inactivation of one or more genes in the adult mouse liver. The method is quick, requiring as little as 1 month from conceptualization to knockout, and highly efficient, enabling editing in >95% of target cells. To highlight its use, we used this system to inactivate, alone or in combination, genes with functions spanning metabolism, mitosis, mitochondrial maintenance, and cell proliferation. CONCLUSIONS: RIME enables the rapid, efficient, and inexpensive analysis of multiple genes in the mouse liver in vivo .


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Camundongos , Animais , Edição de Genes/métodos , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Fígado , Mamíferos
4.
Gastroenterol. hepatol. (Ed. impr.) ; 44(5): 346-354, May.2021. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-221646

RESUMO

Introducción: La videocápsula endoscópica (VCE) ha revolucionado el estudio de las patologías de intestino delgado. El objetivo de este estudio es determinar las indicaciones, hallazgos y rendimiento diagnóstico de la VCE en un registro nacional. Pacientes y métodos: Se realizó un estudio observacional, de corte transversal analítico, analizando los registros de VCE en siete centros del país, se recolectaron diferentes variables. Resultados: Se evaluaron 1.883 estudios de VCE. La edad promedio fue 55,4 años (5,6-94,2). Las indicaciones más frecuentes fueron sospecha de sangrado de intestino delgado (SID) (64,4%), estudio enfermedad de Crohn (15,2%) y diarrea crónica (11,2%). El 54,3% de VCE se prepararon con laxantes. Las lesiones más frecuentes fueron erosiones/úlceras (31,6%), angiectasias (25,7%) y parasitosis (2,7%). El rendimiento diagnóstico (P1+P2, clasificación de Saurin) de VCE en SID fue 60,6%, siendo mayor en SID evidente (66,0%) comparado con SID oculto (56,0%) (P=0,003). Los estudios con mejor preparación presentaban mayor detección de lesiones (93,8% vs. 89,4%) (OR=1,8; IC: 95%: 1,2-2,6; P=0,004). La tasa de complicación de VCE fue 3,1%, con visualización completa del ID en 96,6% y tasa de retención en ID de 0,7%. El 81,5% de VCE se realizaron en forma ambulatoria, y presentaron mayor visualización completa de ID que las hospitalarias (97,1% vs. 94,3%) (OR=2,1; IC: 95%; 1,2-3,5; P=0,008). Conclusiones: Las indicaciones, hallazgos y rendimiento diagnóstico de VCE en Colombia son similares a los reportados en la literatura universal, con alto porcentaje de estudios completos y baja tasa de complicaciones.(AU)


Introduction: The small bowel capsule endoscopy (SBCE) has revolutionised the study of small bowel diseases. The objective of this study is to determine the indications, findings and diagnostic yield of SBCE in a national registry. Patients and methods: An observational, analytical cross-sectional study was carried out, analysing the SBCE records at seven centres in the country, where different variables were collected. Results: 1,883 SBCEs were evaluated. The average age was 55.4 years (5.6-94.2). The most frequent indications were suspicion of small bowel bleeding (SBB) (64.4%), study of Crohn's disease (15.2%) and chronic diarrhoea (11.2%). 54.3% were prepared with laxatives. The most frequent lesions found were erosions/ulcers (31.6%), angioectasias (25.7%) and parasitosis (2.7%). The diagnostic yield (P1+P2, Saurin classification) of SBCE in SBB was 60.6%, being higher in overt SBB (66.0%) compared to occult SBB (56.0%) (P=.003). The studies with better preparation showed higher detection of lesions (93.8% vs. 89.4%) (OR=1.8, CI: 95%: 1.2-2.6; P=.004). The SBCE complication rate was 3.1%, with complete SB visualisation at 96.6% and SB retention rate of 0.7%. 81.5% of SBCEs were performed on an outpatient basis, and presented a greater complete SB visualisation than hospital ones (97.1% vs. 94.3%) (OR=2.1, CI: 95%, 1.2-3.5; P=.008). Conclusions: The indications, findings and diagnostic performance of SBCEs in Colombia are similar to those reported in the literature, with a high percentage of complete studies and a low rate of complications.(AU)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Intestino Delgado/patologia , Intestino Delgado/cirurgia , Hemorragia , Doença de Crohn , Diarreia , Cápsulas Endoscópicas , Colômbia , Gastroenterologia , Gastroenteropatias , Estudos Transversais , Enteropatias Parasitárias
5.
Gastroenterol Hepatol ; 44(5): 346-354, 2021 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33199128

RESUMO

INTRODUCTION: The small bowel capsule endoscopy (SBCE) has revolutionised the study of small bowel diseases. The objective of this study is to determine the indications, findings and diagnostic yield of SBCE in a national registry. PATIENTS AND METHODS: An observational, analytical cross-sectional study was carried out, analysing the SBCE records at seven centres in the country, where different variables were collected. RESULTS: 1,883 SBCEs were evaluated. The average age was 55.4 years (5.6-94.2). The most frequent indications were suspicion of small bowel bleeding (SBB) (64.4%), study of Crohn's disease (15.2%) and chronic diarrhoea (11.2%). 54.3% were prepared with laxatives. The most frequent lesions found were erosions/ulcers (31.6%), angioectasias (25.7%) and parasitosis (2.7%). The diagnostic yield (P1+P2, Saurin classification) of SBCE in SBB was 60.6%, being higher in overt SBB (66.0%) compared to occult SBB (56.0%) (P=.003). The studies with better preparation showed higher detection of lesions (93.8% vs. 89.4%) (OR=1.8, CI: 95%: 1.2-2.6; P=.004). The SBCE complication rate was 3.1%, with complete SB visualisation at 96.6% and SB retention rate of 0.7%. 81.5% of SBCEs were performed on an outpatient basis, and presented a greater complete SB visualisation than hospital ones (97.1% vs. 94.3%) (OR=2.1, CI: 95%, 1.2-3.5; P=.008). CONCLUSIONS: The indications, findings and diagnostic performance of SBCEs in Colombia are similar to those reported in the literature, with a high percentage of complete studies and a low rate of complications.


Assuntos
Endoscopia por Cápsula , Enteropatias/patologia , Intestino Delgado/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Colômbia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Adulto Jovem
6.
Int J Surg Case Rep ; 76: 288-292, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33065488

RESUMO

In the XIX century, the surgeon faces surgical challenges due to the creation of new technologies. Accidental or compressed air-induced injury to the colon and rectum is rare. We present the case of a 45-year-old patient who consults the emergency department, then a high-pressure rectal pneumatic trauma, with clinical findings of peritonism, managed with a Hartmann-type colostomy. and anterior resection of the rectum using laparoscopy, with findings of rectosigmoid perforation. With this, it can be demonstrated that minimally invasive surgery is a feasible approach in hemodynamically unstable patients without contraindication for pneumoperitoneum.

7.
Int J Surg Case Rep ; 73: 268-270, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32721886

RESUMO

INTRODUCTION: Liposarcoma is one of the most common mesenchymal neoplasms in adults. Predominant locations are the retroperitoneum and limbs, it rarely occurs in the gastrointestinal tract. Gastric liposarcoma is extremely rare, with fewer than 30 cases reported around the world. PRESENTATION OF CASE: Here we present the case of a 70-year-old female patient who was diagnosed with gastric liposarcoma and managed with laparoscopic surgical resection. The patient is currently being followed up and is alive without recurrence 12 months after the operation. DISCUSSION: Gastric liposarcoma approach requires proper diagnosis with computed tomography and endoscopy, in order to develop an adequate surgical plan. Laparoscopic en-bloc resection and gastrointestinal reconstruction is the ideal management in this type of patient. CONCLUSION: Gastric liposarcoma is an extremely rare entity, his management consists of wide en-bloc resection with a gastrointestinal reconstruction.

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