965 resultados para Death in literature


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Regulatory T (Treg) cells limit the onset of effective antitumor immunity, through yet-ill-defined mechanisms. We showed the rejection of established ovalbumin (OVA)-expressing MCA101 tumors required both the adoptive transfer of OVA-specific CD8(+) T cell receptor transgenic T cells (OTI) and the neutralization of Foxp3(+) T cells. In tumor-draining lymph nodes, Foxp3(+) T cell neutralization induced a marked arrest in the migration of OTI T cells, increased numbers of dendritic cells (DCs), and enhanced OTI T cell priming. Using an in vitro cytotoxic assay and two-photon live microscopy after adoptive transfer of DCs, we demonstrated that Foxp3(+) T cells induced the death of DCs in tumor-draining lymph nodes, but not in the absence of tumor. DC death correlated with Foxp3(+) T cell-DC contacts, and it was tumor-antigen and perforin dependent. We conclude that Foxp3(+) T cell-dependent DC death in tumor-draining lymph nodes limits the onset of CD8(+) T cell responses.

Relevância:

100.00% 100.00%

Publicador:

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Phosphoinositide 3-kinases produce 3'-phosphorylated phosphoinositides that act as second messengers to recruit other signalling proteins to the membrane(1). Pi3ks are activated by many extracellular stimuli and have been implicated in a variety of cellular responses(1). The Pi3k gene family is complex and the physiological roles of different classes and isoforms are not clear. The gene Pik3r1 encodes three proteins (p85 alpha, p55 alpha and p50 alpha) that serve as regulatory subunits of class I-A Pi3ks (ref. 2). Mice lacking only the p85a isoform are viable but display hypoglycaemia and increased insulin sensitivity correlating with upregulation of the p55 alpha and p50 alpha variants(3). Here we report that loss of all protein products of Pik3r1 results in perinatal lethality. We observed, among other abnormalities, extensive hepatocyte necrosis and chylous ascites, We also noted enlarged skeletal muscle fibres, brown fat necrosis and calcification of cardiac tissue. In liver and muscle, loss of the major regulatory isoform caused a great decrease in expression and activity of class I-A Pi3k catalytic subunits: nevertheless, homozygous mice still displayed hypoglycaemia, lower insulin levels and increased glucose tolerance. Our findings reveal that p55 alpha and/or p50 alpha are required for survival, but not for development of hypoglycaemia, in mice lacking p85 alpha.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The conflict known as the oTroubleso in Northern Ireland began during the late 1960s and is defined by political and ethno-sectarian violence between state, pro-state, and anti-state forces. Reasons for the conflict are contested and complicated by social, religious, political, and cultural disputes, with much of the debate concerning the victims of violence hardened by competing propaganda-conditioning perspectives. This article introduces a database holding information on the location of individual fatalities connected with the contemporary Irish conflict. For each victim, it includes a demographic profile, home address, manner of death, and the organization responsible. Employing geographic information system (GIS) techniques, the database is used to measure, map, and analyze the spatial distribution of conflict-related deaths between 1966 and 2007 across Belfast, the capital city of Northern Ireland, with respect to levels of segregation, social and economic deprivation, and interfacing. The GIS analysis includes a kernel density estimator designed to generate smooth intensity surfaces of the conflict-related deaths by both incident and home locations. Neighborhoods with high-intensity surfaces of deaths were those with the highest levels of segregation ( 90 percent Catholic or Protestant) and deprivation, and they were located near physical barriers, the so-called peacelines, between predominantly Catholic and predominantly Protestant communities. Finally, despite the onset of peace and the formation of a power-sharing and devolved administration (the Northern Ireland Assembly), disagreements remain over the responsibility and ocommemorationo of victims, sentiments that still uphold division and atavistic attitudes between spatially divided Catholic and Protestant populations.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Background: Multiple studies have identified single variables or composite scores that help risk stratify patients at the time of acute lung injury (ALI) diagnosis. However, few studies have addressed the important question of how changes in pulmonary physiologic variables might predict mortality in patients during the subacute or chronic phases of ALI. We studied pulmonary physiologic variables, including respiratory system compliance, P/F ratio and oxygenation index, in a cohort of patients with ALI who survived more than 6 days of mechanical ventilation to see if changes in these variables were predictive of death and whether they are informative about the pathophysiology of subacute ALI.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Objective: The purpose of this study was to describe the value of a formal room blessing ritual held within a long-term care facility, from the perspectives of staff, residents, and family members. Method: A qualitative research study involving interviews with staff, residents, and family members was conducted to examine the perceived value of a room blessing ritual. Results: Twenty-four room blessing attendees participated in the study (nine staff, eight residents, and seven family members). Attendees felt that the room blessing provided an opportunity to formally acknowledge the death of the resident and their grief; the majority felt that this was a positive experience and that it provided an element of closure. Staff members and residents expressed their appreciation for the opportunity to connect with family members of the deceased to express their condolences during the ritual. Participants also identified the inclusivity of the ritual (i.e., an open invitation to all staff, residents, and family members) as a positive aspect that served as a reminder that others shared in their grief. Staff members felt that blessing the room for the new resident was an important component of the ritual, helping to bridge the gap between mourning and welcoming a new person. Staff, residents, and family members felt that the room blessing positively reflected the mission and values of the facility. The most highly valued aspect of the ritual for all attendees was the sharing of stories about the deceased to celebrate that person's life. Significance of results: Long-term care facilities need to recognize that formal supports to manage the bereavement needs of staff and residents, such as a room blessing ritual, should be incorporated into their model for managing end-of-life care, given the relationship between the emotional health of staff and the quality of care provided for residents. © 2012 Cambridge University Press.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Cell and tissue patterning in plant embryo development is well documented. Moreover, it has recently been shown that successful embryogenesis is reliant on programmed cell death (PCD). The cytoskeleton governs cell morphogenesis. However, surprisingly little is known about the role of the cytoskeleton in plant embryogenesis and associated PCD. We have used the gymnosperm, Picea abies , somatic embryogenesis model system to address this question. Formation of the apical-basal embryonic pattern in P. abies proceeds through the establishment of three major cell types: the meristematic cells of the embryonal mass on one pole and the terminally differentiated suspensor cells on the other, separated by the embryonal tube cells. The organisation of microtubules and F-actin changes successively from the embryonal mass towards the distal end of the embryo suspensor. The microtubule arrays appear normal in the embryonal mass cells, but the microtubule network is partially disorganised in the embryonal tube cells and the microtubules disrupted in the suspensor cells. In the same embryos, the microtubule-associated protein, MAP-65, is bound only to organised microtubules. In contrast, in a developmentally arrested cell line, which is incapable of normal embryonic pattern formation, MAP-65 does not bind the cortical microtubules and we suggest that this is a criterion for proembryogenic masses (PEMs) to passage into early embryogeny. In embryos, the organisation of F-actin gradually changes from a fine network in the embryonal mass cells to thick cables in the suspensor cells in which the microtubule network is completely degraded. F-actin de-polymerisation drugs abolish normal embryonic pattern formation and associated PCD in the suspensor, strongly suggesting that the actin network is vital in this PCD pathway.