566 resultados para dying
Resumo:
Analyzing molecular determinants of Plasmodium parasite cell death is a promising approach for exploring new avenues in the fight against malaria. Three major forms of cell death (apoptosis, necrosis and autophagic cell death) have been described in multicellular organisms but which cell death processes exist in protozoa is still a matter of debate. Here we suggest that all three types of cell death occur in Plasmodium liver-stage parasites. Whereas typical molecular markers for apoptosis and necrosis have not been found in the genome of Plasmodium parasites, we identified genes coding for putative autophagy-marker proteins and thus concentrated on autophagic cell death. We characterized the Plasmodium berghei homolog of the prominent autophagy marker protein Atg8/LC3 and found that it localized to the apicoplast. A relocalization of PbAtg8 to autophagosome-like vesicles or vacuoles that appear in dying parasites was not, however, observed. This strongly suggests that the function of this protein in liver-stage parasites is restricted to apicoplast biology.
Resumo:
OBJECTIVES: To investigate unenhanced postmortem 3-T MR imaging (pmMRI) for the detection of pulmonary thrombembolism (PTE) as cause of death. METHODS: In eight forensic cases dying from a possible cardiac cause but with homogeneous myocardium at cardiac pmMRI, additional T2w imaging of the pulmonary artery was performed before forensic autopsy. Imaging was carried out on a 3-T MR system in the axial and main pulmonary artery adapted oblique orientation in situ. In three cases axial T2w pmMRI of the lower legs was added. Validation of imaging findings was performed during forensic autopsy. RESULTS: All eight cases showed homogeneous material of intermediate signal intensity within the main pulmonary artery and/or pulmonary artery branches. Autopsy confirmed the MR findings as pulmonary artery thrombembolism. At lower leg imaging unilateral dilated veins and subcutaneous oedema with or without homogeneous material of intermediate signal intensity within the popliteal vein were found. CONCLUSIONS: Unenhanced pmMRI demonstrates pulmonary thrombembolism in situ. PmMR may serve as an alternative to clinical autopsy, especially when consent cannot be obtained. KEY POINTS: • Postmortem MRI (pmMRI) provides an alternative to clinical autopsy • Fatal pulmonary thrombembolism (PTE) can now be diagnosed using postmortem MRI (pmMRI). • Special attention has to be drawn to the differentiation of postmortem clots.
Resumo:
BACKGROUND Posttraumatic Stress Disorder (PTSD) may occur in patients after exposure to a life-threatening illness. About one out of six patients develop clinically relevant levels of PTSD symptoms after acute myocardial infarction (MI). Symptoms of PTSD are associated with impaired quality of life and increase the risk of recurrent cardiovascular events. The main hypothesis of the MI-SPRINT study is that trauma-focused psychological counseling is more effective than non-trauma focused counseling in preventing posttraumatic stress after acute MI. METHODS/DESIGN The study is a single-center, randomized controlled psychological trial with two active intervention arms. The sample consists of 426 patients aged 18 years or older who are at 'high risk' to develop clinically relevant posttraumatic stress symptoms. 'High risk' patients are identified with three single-item questions with a numeric rating scale (0 to 10) asking about 'pain during MI', 'fear of dying until admission' and/or 'worrying and feeling helpless when being told about having MI'. Exclusion criteria are emergency heart surgery, severe comorbidities, current severe depression, disorientation, cognitive impairment and suicidal ideation. Patients will be randomly allocated to a single 45-minute counseling session targeting either specific MI-triggered traumatic reactions (that is, the verum intervention) or the general role of psychosocial stress in coronary heart disease (that is, the control intervention). The session will take place in the coronary care unit within 48 hours, by the bedside, after patients have reached stable circulatory conditions. Each patient will additionally receive an illustrated information booklet as study material. Sociodemographic factors, psychosocial and medical data, and cardiometabolic risk factors will be assessed during hospitalization. The primary outcome is the interviewer-rated posttraumatic stress level at three-month follow-up, which is hypothesized to be at least 20% lower in the verum group than in the control group using the t-test. Secondary outcomes are posttraumatic stress levels at 12-month follow-up, and psychosocial functioning and cardiometabolic risk factors at both follow-up assessments. DISCUSSION If the verum intervention proves to be effective, the study will be the first to show that a brief trauma-focused psychological intervention delivered within a somatic health care setting can reduce the incidence of posttraumatic stress in acute MI patients. TRIAL REGISTRATION ClinicalTrials.gov: NCT01781247.
Resumo:
OBJECTIVES: Several Asian-American groups are at a higher risk of dying of liver diseases attributable to hepatitis-B infection. This culturally diverse community should be well informed of and protected against liver diseases. The present study assesses the knowledge of hepatitis B before and after a hepatitis-B educational program and determines the infection status of an Asian community. METHODS: Nine Asian communities of Montgomery County, MD, enrolled in the hepatitis-B prevention program between 2005 and 2006. They attended culturally tailored lectures on prevention, completed self-administered pre- and posttests, and received blood screening for the disease. RESULTS: More than 800 Asian Americans participated in the study. Knowledge of prevention was improved after educational delivery. The average infection rate was 4.5%, with Cambodian, Thai, Vietnamese, Chinese and Korean groups having higher infection rates. The age group of 36-45 had the highest percentage of carriers (9.1%). CONCLUSION: Many Asian groups, particularly those of a southeast Asian decent, were subject to a higher probability of hepatitis-B infection. At an increased risk are first-generation Asian immigrants, groups with low immunization rates and those aged 36-45. The findings provide potential directions for focusing preventive interventions on at-risk Asian communities to reduce liver cancer disparities.
Resumo:
At the fore-front of cancer research, gene therapy offers the potential to either promote cell death or alter the behavior of tumor-cells. One example makes use of a toxic phenotype generated by the prodrug metabolizing gene, thymidine kinase (HSVtk) from the Herpes Simplex Virus. This gene confers selective toxicity to a relatively nontoxic prodrug, ganciclovir (GCV). Tumor cells transduced with the HSVtk gene are sensitive to 1-50 $\mu$M GCV; normal tissue is insensitive up to 150-250 $\mu$M GCV. Utilizing these different sensitivities, it is possible to selectively ablate tumor cells expressing this gene. Interestingly, if a HSVtk$\sp+$ expressing population is mixed with a HSVtk$\sp-$ population at high density, all the cells are killed after GCV administration. This phenomenon for killing all neighboring cells is termed the "bystander effect", which is well documented in HSVtk$\sp-$ GCV systems, though its exact mechanism of action is unclear.^ Using the mouse colon carcinoma cell line CT26, data are presented supporting possible mechanisms of "bystander effect" killing of neighboring CT26-tk$\sp-$cells. A major requirement for bystander killing is the prodrug GCV: as dead or dying CT26tk$\sp+$ cells have no toxic effect on neighboring cells in its absence. In vitro, it appears the bystander effect is due to transfer of toxic GCV-metabolites, through verapamil sensitive intracellular-junctions. Additionally, possible transfer of the HSVtk enzyme to bystander cells after GCV addition, may play a role in bystander killing. A nude mouse model suggests that in a 50/50 (tk$\sp+$/tk$\sp-$) mixture of CT26 cells the bystander eradication of tumors does not involve an immune component. Additionally in a possible clinical application, the "bystander effect" can be directly exploited to eradicate preexisting CT26 colon carcinomas in mice by intratumoral implantation of viable or lethally irradiated CT26tk$\sp+$ cells and subsequent GCV administration. Lastly, an application of this toxic phenotype gene to a clinical marking protocol utilizing a recombinant adenoviral vector carrying the bifunctional protein GAL-TEK to eradicate spontaneously-arisen or vaccine-induced fibrosarcomas in cats is demonstrated. ^
Resumo:
The desire to promote efficient allocation of health resources and effective patient care has focused attention on home care as an alternative to acute hospital service. in particular, clinical home care is suggested as a substitute for the final days of hospital stay. This dissertation evaluates the relationship between hospital and home care services for residents of British Columbia, Canada beginning in 1993/94 using data from the British Columbia Linked Health database. ^ Lengths of stay for patients referred to home care following hospital discharge are compared to those for patients not referred to home care. Ordinary least squares regression analysis adjusts for age, gender, admission severity, comorbidity, complications, income, and other patient, physician, and hospital characteristics. Home care clients tend to have longer stays in hospital than patients not referred to home care (β = 2.54, p = 0.0001). Longer hospital stays are evident for all home care client groups as well as both older and younger patients. Sensitivity analysis for referral time to direct care and extreme lengths of stay are consistent with these findings. Two stage regression analysis indicates that selection bias is not significant.^ Patients referred to clinical home care also have different health service utilization following discharge compared to patients not referred to home care. Home care nursing clients use more medical services to complement home care. Rehabilitation clients initially substitute home care for physiotherapy services but later are more likely to be admitted to residential care. All home care clients are more likely to be readmitted to hospital during the one year follow-up period. There is also a strong complementary association between direct care referral and homemaker support. Rehabilitation clients have a greater risk of dying during the year following discharge. ^ These results suggest that home care is currently used as a complement rather than a substitute for some acute health services. Organizational and resource issues may contribute to the longer stays by home care clients. Program planning and policies are required if home care is to provide an effective substitute for acute hospital days. ^
Resumo:
Epidemiologic case-control studies of small groups of childhood nervous system tumor patients have suggested that parental employment in occupations with exposure to hydrocarbons is a risk factor for disease. The main focus of this case-control study was to assess the paternal occupation at the time of birth of offspring who later developed childhood intracranial and spinal tumors. All children under 15 years of age dying of such tumors in Texas, during the period 1964-1980, were selected as cases. Disease and demographic data were abstracted from death certificates. The birth certificate for each child of the final group of 499 cases was located and parental occupation information, as well as demographic and obstetric data, were collected. The comparison group consisted of a random sample from all Texas live births with the same birth year, race and sex distribution as the cases.^ The paternal occupations were categorized into broad classifications of those involving hydrocarbon exposure versus those that did not, based on the occupation criteria used in the previous studies. Odds ratios did not indicate any increased risk associated with general paternal hydrocarbon exposure in the workplace. In prior studies, increased risk estimates were detected with narrower groups of occupations involving exposure to hydrocarbon materials. The data from this study were classified according to these groups, and again, no increased risks were indicated except for a statistically insignificant but elevated odds ratio for fathers who were paper and pulp mill workers.^ Odds ratios were calculated for specific occupations and industries previously implicated as risk factors. Significantly associated odds ratios (OR) were detected for electricians (OR = 3.5), especially those working for construction companies (OR = 10.0), for employment in the printing occupations (OR = 4.5), particularly graphic arts workers (OR = 21.9), and in the electronics and electronic machinery industries (OR = 3.5). Analysis of the petroleum refining and chemical industries, which were not found in previous study populations, revealed significantly elevated odds ratios of 3.0 for occupations with probable heavy exposure to chemicals and petroleum compounds and 10.0 for salesmen of chemical products. ^
Resumo:
Prematurely born babies are often treated with glucocorticoids. We studied the consequences of an early postnatal and short dexamethasone treatment (0.1-0.01 microg/g, days 1-4) on lung development in rats, focusing on its influence on peaks of cell proliferation around day 4 and of programmed cell death at days 19-21. By morphological criteria, we observed a dexamethasone-induced premature maturation of the septa (day 4), followed by a transient septal immatureness and delayed alveolarization leading to complete rescue of the structural changes. The numbers of proliferating (anti-Ki67) and dying cells (TdT-mediated dUTP nick end labeling) were determined and compared with controls. In dexamethasone-treated animals, both the peak of cell proliferation and the peak of programmed cell death were reduced to baseline, whereas the expression of tissue transglutaminase (transglutaminase-C), another marker for postnatal lung maturation, was not significantly altered. We hypothesize that a short neonatal course of dexamethasone leads to severe but transient structural changes of the lung parenchyma and influences the balance between cell proliferation and cell death even in later stages of lung maturation.
Resumo:
The rat lung undergoes the phase of maturation of the alveolar septa and of the parenchymal microvascular network mainly during the third postnatal week. Speculating that programmed cell death may contribute to the thinning of the alveolar septa, we searched for the presence of DNA fragmentation in rat lungs between postnatal days 6 and 36 using the TUNEL procedure. The number of positive nuclei was compared at different days. We observed an 8-fold increase of programmed cell death toward the end of the third week as compared to the days before and after this time point. The precise timing of the appearance of the peak depended on the size of the litter. Double-labeling for DNA fragmentation (TUNEL) and for type I and type II epithelial cells (antibodies E11 and MNF-116), as well as morphologic studies at electron microscopic level, revealed that during the peak of programmed cell death mainly fibroblasts and type II epithelial cells were dying. While both dying cell types were TUNEL-positive, nuclear fragments and apoptotic bodies were exclusively observed in the dying fibroblasts. We conclude that programmed cell death is involved in the structural maturation of the lung by reducing the number of fibroblasts and type II epithelial cells in the third postnatal week. We observed that the dying fibroblasts are cleared by neighboring fibroblasts in a later stage of apoptosis, and we hypothesize that type II epithelial cells are cleared by alveolar macrophages in early stages of the programmed cell death process.
Resumo:
OBJECTIVES This study aimed to demonstrate that the presence of late gadolinium enhancement (LGE) is a predictor of death and other adverse events in patients with suspected cardiac sarcoidosis. BACKGROUND Cardiac sarcoidosis is the most important cause of patient mortality in systemic sarcoidosis, yielding a 5-year mortality rate between 25% and 66% despite immunosuppressive treatment. Other groups have shown that LGE may hold promise in predicting future adverse events in this patient group. METHODS We included 155 consecutive patients with systemic sarcoidosis who underwent cardiac magnetic resonance (CMR) for workup of suspected cardiac sarcoid involvement. The median follow-up time was 2.6 years. Primary endpoints were death, aborted sudden cardiac death, and appropriate implantable cardioverter-defibrillator (ICD) discharge. Secondary endpoints were ventricular tachycardia (VT) and nonsustained VT. RESULTS LGE was present in 39 patients (25.5%). The presence of LGE yields a Cox hazard ratio (HR) of 31.6 for death, aborted sudden cardiac death, or appropriate ICD discharge, and of 33.9 for any event. This is superior to functional or clinical parameters such as left ventricular (LV) ejection fraction (EF), LV end-diastolic volume, or presentation as heart failure, yielding HRs between 0.99 (per % increase LVEF) and 1.004 (presentation as heart failure), and between 0.94 and 1.2 for potentially lethal or other adverse events, respectively. Except for 1 patient dying from pulmonary infection, no patient without LGE died or experienced any event during follow-up, even if the LV was enlarged and the LVEF severely impaired. CONCLUSIONS Among our population of sarcoid patients with nonspecific symptoms, the presence of myocardial scar indicated by LGE was the best independent predictor of potentially lethal events, as well as other adverse events, yielding a Cox HR of 31.6 and of 33.9, respectively. These data support the necessity for future large, longitudinal follow-up studies to definitely establish LGE as an independent predictor of cardiac death in sarcoidosis, as well as to evaluate the incremental prognostic value of additional parameters.
Resumo:
AIMS As 4-day-old mice of the severe spinal muscular atrophy (SMA) model (dying at 5-8 days) display pronounced neuromuscular changes in the diaphragm but not the soleus muscle, we wanted to gain more insight into the relationship between muscle development and the emergence of pathological changes and additionally to analyse intercostal muscles which are affected in human SMA. METHODS Structures of muscle fibres and neuromuscular junctions (NMJs) of the diaphragm, intercostal and calf muscles of prenatal (E21) and postnatal (P0 and P4) healthy and SMA mice were analysed by light and transmission electron microscopy. NMJ innervation was studied by whole mount immunofluorescence in diaphragms of P4 mice. RESULTS During this period, the investigated muscles still show a significant neck-to-tail developmental gradient. The diaphragm and calf muscles are most and least advanced, respectively, with respect to muscle fibre fusion and differentiation. The number and depth of subsynaptic folds increases, and perisynaptic Schwann cells (PSCs) acquire a basal lamina on their outer surface. Subsynaptic folds are connected to an extensive network of tubules and beaded caveolae, reminiscent of the T system in adult muscle. Interestingly, intercostal muscles from P4 SMA mice show weaker pathological involvement (that is, vacuolization of PSCs and perineurial cells) than those previously described by us for the diaphragm, whereas calf muscles show no pathological changes. CONCLUSION SMA-related alterations appear to occur only when the muscles have reached a certain developmental maturity. Moreover, glial cells, in particular PSCs, play an important role in SMA pathogenesis.
Resumo:
BACKGROUND To investigate the role of nonsurgical treatment for early-stage esophageal cancer, we compared the outcomes of local therapy to esophagectomy, using a large, national database. METHODS Five-year cancer-specific and overall survival (OS) of patients, with T1N0M0 squamous cell or adenocarcinoma of the mid or distal esophagus treated with either surgery or local therapy, with ablative and/or excision techniques, in the Surveillance Epidemiology and End Results cancer registry from 1998 to 2008, were compared using the Kaplan-Meier approach, and multivariable and propensity-score adjusted Cox proportional hazard, and competing risk models. RESULTS Of 1458 patients with T1N0 esophageal cancer, 1204 (83%) had surgery and 254 (17%) had local therapy only. The use of local therapy increased significantly from 8.1% in 1998 to 24.1% in 2008 (p < 0.001). The 5-year OS after local excisional therapy and surgery was not significantly different (55.5% versus 64.1% respectively, p = 0.07), and 5-year cancer-specific survival (CSS) also did not differ (81.7% versus 75.8%, p = 0.10). However, after propensity-score adjustment, CSS was better for patients who underwent local therapy compared with those who underwent surgery (hazard ratio: 0.46, 95% confidence interval: 0.27-0.77, p = 0.003), whereas OS remained similar. CONCLUSION The use of local therapy for T1N0 esophageal cancers increased significantly from 1998 to 2008. Compared with those treated with esophagectomy, patients treated with local therapy had similar OS but improved CSS, indicating a higher chance of dying from other causes. Further studies are needed to confirm the oncologic efficacy of local therapy when used in patients whose lifespans are not limited by conditions other than esophageal cancer.
Resumo:
The proposed paper will present first results of a research project investigating how nursing homes in Switzerland deal with migrant elders who are in intensive need of care. Focusing on the end-of-life in institutional care settings, the intention is to explore the dimensions of ‘doing death’ in Swiss nursing homes when the elderly involved are of migrant background. The focus is laid on the co-construction of end of life in interactions between residents of migrant background and professional carers involved (often of migrant background themselves), and will thereby focus on processes of ‘doing diversity’ while ‘doing death’. To do so, we chose an ethnographic approach focusing on the participant observation of everyday practices of ‘doing death’ and ‘death work’ and on interviewing staff, residents and their relatives. Caring for ageing migrants at the end of their lives is studied in different types of assisted living at the end of life: The field of research was entered by studying a group specific department for residents of so-called ‘Mediterranean’ background. It was contrasted by a department stressing the individuality of each resident but including a considerable number of residents with migrant background. We are interested in how (and if at all) specific forms of ‘doing community’ within different types of departments may also lead to specific ways of ‘doing death’, which aim at a stronger embeddedness of dying trajectories in social relations of reciprocity and exchange. Furthermore, migrant ‘doing death’ is expected to be particularly negotiable since the potential diversities of symbolic reference systems and daily practices are widened. If the respective resident is limited in his/her capacities to play an active part in negotiating about ‘good care’ and ‘good dying’ – either due to language competences, which would be migrant specific, or due to degenerative diseases, which is not migrant specific – the field of negotiations will be left up to the professionals within the organization (and to the relatives, which are, however, not constantly present). Strategies of stereotyping the ‘other’ as well as driving nurses, caring aides and other professionals of migrant background into roles of ‘cultural experts’ or ‘transcultural translators’ are expected to be common in such situations. However, the task of negotiating what would be a ‘good dying’ and what measures are appropriate is always at stake in contemporary heterogeneous societies. Therefore we would argue that studying dying processes involving migrant residents is looking at paradigmatic manifestations of doing death in recent contexts of reflexive modernity.
Resumo:
The objective of this study is to determine if quality of care, symptoms of depression, disease characteristics and quality of life of patients with amyotrophic lateral sclerosis (ALS) are related to requesting euthanasia or physician-assisted suicide (EAS) and dying due to EAS. Therefore, 102 ALS patients filled out structured questionnaires every 3 months until death and the results were correlated with EAS. Thirty-one percent of the patients requested EAS, 69 % of whom eventually died as a result of EAS (22 % of all patients). Ten percent died during continuous deep sedation; only one of them had explicitly requested death to be hastened. Of the patients who requested EAS, 86 % considered the health care to be good or excellent, 16 % felt depressed, 45 % experienced loss of dignity and 42 % feared choking. These percentages do not differ from the number of patients who did not explicitly request EAS. The frequency of consultations of professional caregivers and availability of appliances was similar in both groups. Our findings do not support continuous deep sedation being used as a substitute for EAS. In this prospective study, no evidence was found for a relation between EAS and the quality and quantity of care received, quality of life and symptoms of depression in patients with ALS. Our study does not support the notion that unmet palliative care needs are related to EAS.
Resumo:
BACKGROUND The value of radical prostatectomy (RP) as an approach for very high-risk prostate cancer (PCa) patients is controversial. To examine the risk of 10-year cancer-specific mortality (CSM) and other-cause mortality (OCM) according to clinical and pathological characteristics of very high-risk cT3b/4 PCa patients treated with RP as the primary treatment option. METHODS In a multi-institutional cohort, 266 patients with very high-risk cT3b/4 PCa treated with RP were identified. All patients underwent RP and pelvic lymph-node dissection. Competing-risk analyses assessed 10-year CSM and OCM before and after stratification for age and Charlson comorbidity index (CCI). RESULTS Overall, 34 (13%) patients died from PCa and 73 (28%) from OCM. Ten-year CSM and OCM rates ranged from 5.6% to 12.9% and from 10% to 38%, respectively. OCM was the leading cause of death in all subgroups. Age and comorbidities were the main determinants of OCM. In healthy men, CSM rate did not differ among age groups (10-year CSM rate for ⩽64, 65-69 and ⩾70 years: 16.2%, 11.5% and 17.1%, respectively). Men with a CCI ⩾1 showed a very low risk of CSM irrespective of age (10-year CSM: 5.6-6.1%), whereas the 10-year OCM rates increased with age up to 38% in men ⩾70 years. CONCLUSION Very high-risk cT3b/4 PCa represents a heterogeneous group. We revealed overall low CSM rates despite the highly unfavorable clinical disease. For healthy men, CSM was independent of age, supporting RP even for older men. Conversely, less healthy patients had the highest risk of dying from OCM while sharing very low risk of CSM, indicating that this group might not benefit from an aggressive surgical treatment. Outcome after RP as the primary treatment option in cT3b/4 PCa patients is related to age and comorbidity status.