888 resultados para Causing death
Resumo:
Phosphatidylcholine-specific phospholipase C (PC-PLC) is a necessary intermediate in transducing apoptotic signals for tumor necrosis factor and Fas/Apo-1 ligands in nonneuronal cells. The data presented here show that PC-PLC also is required in oxidative glutamate-induced programmed cell death of both immature cortical neurons and a hippocampal nerve cell line, HT22. In oxidative glutamate toxicity, which is distinct from excitotoxicity, glutamate interferes with cystine uptake by blocking the cystine/glutamate antiporter, indirectly causing a depletion of intracellular glutathione. A PC-PLC inhibitor blocks oxidative glutamate toxicity, and exogenous PC-PLC potentiates glutamate toxicity. The inhibition of PC-PLC uncouples the cystine uptake from glutamate inhibition, allowing the maintenance of glutathione synthesis and cell viability. These data suggest that PC-PLC modulates neuronal cell death through a mechanism that is distinct from that involved in nonneuronal apoptosis.
Resumo:
The correlation between telomerase activity and human tumors has led to the hypothesis that tumor growth requires reactivation of telomerase and that telomerase inhibitors represent a class of chemotherapeutic agents. Herein, we examine the effects of inhibition of telomerase inside human cells. Peptide nucleic acid and 2′-O-MeRNA oligomers inhibit telomerase, leading to progressive telomere shortening and causing immortal human breast epithelial cells to undergo apoptosis with increasing frequency until no cells remain. Telomere shortening is reversible: if inhibitor addition is terminated, telomeres regain their initial lengths. Our results validate telomerase as a target for the discovery of anticancer drugs and supply general insights into the properties that successful agents will require regardless of chemical type. Chemically similar oligonucleotides are in clinical trials and have well characterized pharmacokinetics, making the inhibitors we describe practical lead compounds for testing for an antitelomerase chemotherapeutic strategy.
Resumo:
Retinitis pigmentosa (RP) is a group of inherited blinding diseases caused by mutations in multiple genes including RDS. RDS encodes rds/peripherin (rds), a 36-kDa glycoprotein in the rims of rod and cone outer-segment (OS) discs. Rom1 is related to rds with similar membrane topology and the identical distribution in OS. In contrast to RDS, no mutations in ROM1 alone have been associated with retinal disease. However, an unusual digenic form of RP has been described. Affected individuals in several families were doubly heterozygous for a mutation in RDS causing a leucine 185 to proline substitution in rds (L185P) and a null mutation in ROM1. Neither mutation alone caused clinical abnormalities. Here, we generated transgenic/knockout mice that duplicate the amino acid substitutions and predicted levels of rds and rom1 in patients with RDS-mediated digenic and dominant RP. Photoreceptor degeneration in the mouse model of digenic RP was faster than in the wild-type and monogenic controls by histological, electroretinographic, and biochemical analysis. We observed a positive correlation between the rate of photoreceptor loss and the extent of OS disorganization in mice of several genotypes. Photoreceptor degeneration in RDS-mediated RP appears to be caused by a simple deficiency of rds and rom1. The critical threshold for the combined abundance of rds and rom1 is ≈60% of wild type. Below this value, the extent of OS disorganization results in clinically significant photoreceptor degeneration.
Resumo:
This essay explores the political significance of Balinese death/thrash fandom. In the early 1990s, the emergence of a death/thrash scene in Bali paralleled growing criticism of accelerated tourism development on the island. Specifically, locals protested the increasing ubiquity of Jakarta, 'the centre', cast as threatening to an authentically 'low', peripheral Balinese culture. Similarly, death/thrash enthusiasts also gravitated toward certain fringes, although they rejected dominant notions of Balinese-ness by gesturing elsewhere, toward a global scene. The essay explores the ways in which death/thrash enthusiasts engaged with local discourses by coveting their marginality, and aims to demonstrate how their articulations of 'alien-ness' contributed in important ways to a broader regionalism.
Resumo:
Background. There is considerable debate regarding the clinical issues surrounding the wish to hasten death (WTHD) in the terminally ill. The clinical factors contributing to the WTHD need further investigation among the terminally ill in order to enhance understanding of the clinical assessment and treatment needs that underlie this problem. A more detailed understanding may assist with the development of appropriate therapeutic interventions. Method. A sample of terminally ill cancer patients (N=256) recruited from an in-patient hospice unit, home palliative care service and a general hospital palliative care consulting service from Brisbane Australia between 1998–2001 completed a questionnaire assessing psychological (depression and anxiety), social (family relationship, social support, level of burden on others) and the impact of physical symptoms. The association between these factors and the WTHD was investigated. Results. A high WTHD was reported by 14% of patients. A discriminant function analysis revealed that the following variables were associated with a high WTHD (P<0·001): higher levels of depressive symptoms, being admitted to an in-patient hospice setting, a greater perception of being a burden on others, lower family cohesion, lower levels of social support, higher levels of anxiety and greater impact of physical symptoms. Conclusions. Psychological and social factors are related to a WTHD among terminally ill cancer patients. Greater attention needs to be paid to the assessment of psychological and social issues in order to provide appropriate therapeutic interventions for terminally ill patients.
Resumo:
There is a paucity of research that has directly examined the role of the health professional in dealing with a terminally ill patient's wish to hasten death (WTHD) and the implications of this for the support and services needed in the care for a dying patient. Themes to emerge from a qualitative analysis of interviews conducted on doctors (n=24) involved in the treatment and care of terminally ill patients were (i) the doctors' experiences in caring for their patients (including themes of emotional demands/expectations, the duration of illness, and the availability of palliative care services); (ii) the doctors' perception of the care provided to their respective patients (comprising themes concerning satisfaction with the care for physical symptoms, for emotional symptoms, or overall care); (iii) the doctors' attitudes to euthanasia and (iv) the doctors' perception of their patients' views/beliefs regarding euthanasia and hastened death. When responses were categorised according to the patients' level of a WTHD, the theme concerning the prolonged nature of the patients' illnesses was prominent in the doctor group who had patients with the highest WTHD, whereas there was only a minority of responses concerning support from palliative care services and satisfaction with the level of emotional care in this group. This exploratory study presents a set of descriptive findings identifying themes among a small group of doctors who have been involved in the care of terminally ill cancer patients, to investigate factors that may be associated with the WTHD among these patients. The pattern of findings suggest that research investigating the doctor-patient interaction in this setting may add to our understanding of the problems (for patients and their doctors) that underpins the wish to hasten death in the terminally ill.
Resumo:
This exploratory study investigated factors associated with the wish to hasten death among a sample of terminally ill cancer patients. Semi-structured interviews conducted on a total of 72 hospice and home palliative care patients were subjected to qualitative analysis using QSRNUDIST. The main themes to emerge suggested that patients with a high wish to hasten death had greater concerns with physical symptoms and psychologica l suffering, perceived themselves to be more of a burden to others, and experienced higher levels of demoralization, while also reporting less confidence in symptom control, fewer social supports, less satisfaction with life experiences and fewer religious beliefs when compared with patients who had a moderate or no wish to hasten death. The implications of these findings will be discussed.
Resumo:
The common brown leafhopper, Orosius orientalis (Matsumura) (Homoptera: Cicadellidae), previously described as Orosius argentatus (Evans), is an important vector of several viruses and phytoplasmas worldwide. In Australia, phytoplasmas vectored by O. orientalis cause a range of economically important diseases, including legume little leaf (Hutton & Grylls, 1956), tomato big bud (Osmelak, 1986), lucerne witches broom (Helson, 1951), potato purple top wilt (Harding & Teakle, 1985), and Australian lucerne yellows (Pilkington et al., 2004). Orosius orientalis also transmits Tobacco yellow dwarf virus (TYDV; genus Mastrevirus, family Geminiviridae) to beans, causing bean summer death disease (Ballantyne, 1968), and to tobacco, causing tobacco yellow dwarf disease (Hill, 1937, 1941). TYDV has only been recorded in Australia to date. Both diseases result in significant production and quality losses (Ballantyne, 1968; Thomas, 1979; Moran & Rodoni, 1999). Although direct damage caused by leafhopper feeding has been observed, it is relatively minor compared to the losses resulting from disease (P Tr E bicki, unpubl.).
Resumo:
This paper details research conducted in Queensland during the first year of operation of the new Coroners Act 2003. Information was gathered from all completed investigations between December 2003 and December 2004 across five categories of death: accidental, suicide, natural, medical and homicide. It was found that 25 percent of the total number of Indigenous deaths recorded in 2004 were reported to, and investigated by, the Coroner, in comparison to 9.4 percent of non-Indigenous deaths. Moreover, Indigenous people were found to be over-represented in each category of death, except in death in a medical setting, where they were absent.