RESUMO
A 75-year-old male patient underwent endoscopic submucosal dissection (ESD) for early gastric cancer. The ESD ulcer bleeding occurred 7 days post-ESD, and he underwent endoscopic clipping hemostasis. Afterward, the patient presented with acute cholecystitis and cholangitis, thereby developing sclerosing cholangitis. His hepatic failure worsened and he died 15 months post-ESD although we performed endoscopic dilations for bile duct stenosis and administered antibiotics. We considered the condition to be related to secondary sclerosing cholangitis in critically ill patients (SSC-CIP) caused by bile duct ischemia and cholangitis.
Assuntos
Colangite Esclerosante , Colangite , Ressecção Endoscópica de Mucosa , Hemostase Endoscópica , Neoplasias Gástricas , Masculino , Humanos , Idoso , Colangite Esclerosante/complicações , Colangite Esclerosante/cirurgia , Úlcera , Neoplasias Gástricas/complicaçõesRESUMO
T-cell population consists of two major subsets, CD4+ T cells and CD8+ T cells, which can be distinguished by the expression of CD4 or CD8 molecules, respectively. Although they play quite different roles in the immune system, many of their basic cellular processes such as proliferation following stimulation are presumably common. In this study, we have carefully analyzed time-course of G0/1 transition as well as cell cycle progression in the two subsets of quiescent T-cell population following in vitro growth stimulation. We found that CD8+ T cells promote G0/1 transition more rapidly and drive their cell cycle progression faster compared to CD4+ T cells. In addition, expression of CD25 and effects of its blockade revealed that IL-2 is implicated in the rapid progression, but not the earlier G0/1 transition, of CD8+ T cells.
Assuntos
Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Fase G1/genética , Ativação Linfocitária/imunologia , Fase de Repouso do Ciclo Celular/genética , Animais , Proliferação de Células , Células Cultivadas , Interleucina-2/metabolismo , Subunidade alfa de Receptor de Interleucina-2/biossíntese , CamundongosRESUMO
Peripheral T cells are in G0 phase and do not proliferate. When they encounter an antigen, they enter the cell cycle and proliferate in order to initiate an active immune response. Here, we have determined the first two cell cycle times of a leading population of CD4(+) T cells stimulated by PMA plus ionomycin in vitro. The first cell cycle began around 10 h after stimulation and took approximately 16 h. Surprisingly, the second cell cycle was extremely rapid and required only 6 h. T cells might have a unique regulatory mechanism to compensate for the shortage of the gap phases in cell cycle progression. This unique feature might be a basis for a quick immune response against pathogens, as it maximizes the rate of proliferation.