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21.
Wang X Sarkar A Cicchetti F Yu M Zhu A Jokivarsi K Saint-Pierre M Brownell AL 《Journal of the neurological sciences》2005,231(1-2):57-66
To investigate efficacy of cystamine induced neuroprotection, we conducted PET imaging studies of cerebral glucose metabolism with [(18)F]FDG (2-deoxy-2-[(18)F]fluoro-d-glucose) and striatal dopamine D2 receptor function with [(11)C]raclopride in R6/2 transgenic Huntington mice. In the control mice, exponentially decreasing glucose utilization was observed in the striatum N(str) [SUV]=(41.75+/-11.80)(58,str)*exp(-(0.041+/-0.007)*t [days]); cortex N(cort) [SUV]=24.14+/-3.66)(58,cort)*exp(-(0.043+/-0.007)*t [days]); and cerebellum N(cer) [SUV]=(34.97+/-10.58)(58,cer)*exp(-(0.037+/-0.008)*t [days]) as a function of age starting at 58 days. Given that the underlying degeneration rate in the cystamine treated mice is similar to that observed in control animals, the protection coefficient (beta) calculated from the equation N(t)=N(58)*exp(-(1-beta)*k*t) was 0.133+/-0.035 for the striatum; 0.122+/-0.028 for the cortex and 0.224+/-00.042 for the cerebellum with a dose of 100 mg/kg. The 50 mg/kg cystamine dose provided significant protection only for the striatum and only minor protection was obtained using lower doses. Striatal binding potential of [(11)C]raclopride was 1.059+/-0.030 in the control mice, and enhanced in the cystamine treated animals in a dose dependent manner up to 1.245+/-0.063 using the 100 mg/kg dose. Histological analysis confirmed cystamine induced neuroprotection of striatal and cortical neurons and Nissl staining revealed that formation of cellular inclusions was reversed in a dose dependent manner. Cerebral imaging and histological evidence support the use of cystamine as a neuroprotective agent for Huntington's disease (HD) pathology. 相似文献
22.
Systemic exposure to proteasome inhibitors causes a progressive model of Parkinson's disease 总被引:34,自引:0,他引:34
Environmental toxins have been implicated in the etiology of Parkinson's disease. Recent findings of defects in the ubiquitin-proteasome system in hereditary and sporadic forms of the illness suggest that environmental proteasome inhibitors are candidate PD-inducing toxins. Here, we systemically injected six doses of naturally occurring (epoxomicin) or synthetic (Z-lle-Glu(OtBu)-Ala-Leu-al [PSI]) proteasome inhibitors into adult rats over a period of 2 weeks. After a latency of 1 to 2 weeks, animals developed progressive parkinsonism with bradykinesia, rigidity, tremor, and an abnormal posture, which improved with apomorphine treatment. Positron emission tomography demonstrated reduced carbon-11-labeled 2beta-carbomethoxy-3beta-(4-fluorophenyl)tropane (CFT) binding to dopaminergic nerve terminals in the striatum, indicative of degeneration of the nigrostriatal pathway. Postmortem analyses showed striatal dopamine depletion and dopaminergic cell death with apoptosis and inflammation in the substantia nigra pars compacta. In addition, neurodegeneration occurred in the locus coeruleus, dorsal motor nucleus of the vagus, and the nucleus basalis of Meynert. At neurodegenerative sites, intracytoplasmic, eosinophilic, alpha-synuclein/ubiquitin-containing, inclusions resembling Lewy bodies were present in some of the remaining neurons. This animal model induced by proteasome inhibitors closely recapitulates key features of PD and may be valuable in studying etiopathogenic mechanisms and putative neuroprotective therapies for the illness. 相似文献
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In Finland, adults born in 1961 or later were progressively entitled to subsidies for dental care from private practitioners during 1986-90, while at the same time having access to care in the Public Dental Service. The aim of this study was to compare the effects of attendance frequency of private dental care on treatment costs and treatment spectrum for the heaviest and lowest users over a period. Three separate cohorts of recipients of reimbursements were formed, using the Social Insurance Register. The highest and lowest cost groups in 1986, 1990, and 1994 were followed up to 1997. Initially, the mean numbers of visits were 1.2-1.3 and 5.2-5.6 and cost Euro 48 53 and Euro 358-379 among low users and heavy users, respectively, in all cohorts. Among the heavy users (the high-cost category) infrequent attendance was related to higher and frequent attendance to lower mean annual costs of care. Among the low users (the low-cost category the opposite was true. Those who initially belonged to the high-cost category received in 1997 significantly more (P < 0.01) restorative treatment and, to a lesser extent, more (P < 0.01) preventive and periodontal treatment than those belonging to the low-cost category. Frequent dental care seemed to benefit those who received a lot of care. Frequency of attendance was not associated with being a low or a heavy user, indicating rigid check-up routines. The inclusion of simple oral health data would greatly improve the usefulness of the register as an evaluation tool for health-political decisions. 相似文献
25.
Svedström-Oristo AL Pietilä T Pietilä I Helenius H Peutzfeldt P Varrela J 《Acta odontologica Scandinavica》2002,60(3):160-166
There is no general agreement on criteria that could be applied to distinguish between orthodontically acceptable and non-acceptable occlusions after the completion of dental development. The aim of the present study was to analyse morphological and functional features that could be used as an index to define an acceptable occlusion in young adults. Three expert panels representing specialists in orthodontics and stomatognathic physiology participated in a modified Delphi method. Each panel responded to a questionnaire concerning the usefulness of various occlusal features, and a set of characteristics was selected on the basis of the responses; thereafter, applicability of the chosen characteristics and their cut-offs for an acceptable non-acceptable dichotomy was tested clinically. To obtain a consensus level of 100%, the last panel session was completed with a group discussion. Assessments made using the morphological criteria were compared with those made with the dental health component of the Index of Orthodontic Treatment Need. The selected morphological characteristics consisted of overjet, overbite, canine relationship, crossbite, scissors bite and midline deviation. The functional evaluation comprised assessments of discrepancy between the centric relation and the intercuspal position, working- and non-working-side contacts and protrusion contacts. The dental health component and our morphological criteria showed different sensitivity to contact point displacements, interdigitation in buccal segments and increased overbite. This study provides a set of morphological and functional indicators reflecting the current consensus opinion of Finnish professionals. Further studies are needed to analyse the reproducibility of assessment of the characteristics included. 相似文献
26.
27.
Encountering patients with chronic fatigue syndrome (CFS) or fibromyalgia can cause dilemmas for physicians due to the uncertainty inherent in these illnesses. The aim of this study was to investigate: (1). How physicians in a Swedish sample describe and categorize patients with CFS and fibromyalgia; (2). What the character of CFS and fibromyalgia, with regard to diagnosing, treatment and medical knowledge/aetiology, mean to the physicians in encounters with patients; and (3). Which strategies physicians describe that they use in the encounter with these patients. Semi-structured interviews were carried out with 26 physicians, specialists in various fields who all had some experience of either CFS or fibromyalgia. The results suggest that there is a discrepancy between the ideal role of the physician and reality in the everyday work in interaction with these patients. This may lead to the professional role being questioned. Different strategies are developed to handle the encounters with these patients. The results also illuminate the physician's interpretations of patients in moralising terms. Conditions given the status of illness were regarded, for example, as less serious by the physicians than those with disease status. Scepticism was expressed regarding especially CFS, but also fibromyalgia. Moreover, it is shown how the patients are characterised by the physicians as ambitious, active, illness focused, demanding and medicalising. The patient groups in question do not always gain full access to the sick-role, in part as a consequence of the conditions not being defined as diseases. 相似文献
28.
OBJECTIVES: The objective of the study was to investigate the content, criterion, and construct validity of a single-item measure of stress symptoms. Such a concise measure would be useful in monitoring stress at work. The criteria for validity were convergence with conceptionally close measures, the plausibility of associations with health and work characteristics, and the power to discriminate between groups. METHODS: Four sets of independent cross-sectional data were used. The first data set, from Finland Post, comprised symptoms of ill health and mental resources (N=1014). The second, from four Nordic countries, included well-known validated scales on exhaustion, mental health, sleep, vitality, and optimism, and therefore the convergence between the measures could be studied (N=1015). The third, from a metal factory, included three indicators of health and four work characteristics (N=773). The fourth, representing the Finnish working population, described group differences in stress symptoms (N=2156) and allowed comparison with a study on emotional exhaustion in the working population. Distributions, correlations, and factor analysis were used for the study. RESULTS: The stress-symptoms item converged with items on psychological symptoms and sleep disturbances and with validated measures of well-being. It had theoretically grounded associations with indicators of health and psychosocial work characteristics, and it discriminated between gender and age groups and industrial branches in accordance with the validated emotional exhaustion scale. CONCLUSIONS: The stress-symptoms item showed satisfactory content, criterion, and construct validity for group-level analysis. It is suggested that the longer scales used to measure psychological stress can be replaced with it in survey research. 相似文献
29.
Fluorescence resonance energy transfer reveals a binding site of a photosensitizer for photodynamic therapy 总被引:6,自引:0,他引:6
Morris RL Azizuddin K Lam M Berlin J Nieminen AL Kenney ME Samia AC Burda C Oleinick NL 《Cancer research》2003,63(17):5194-5197
Phthalocyanine (Pc) 4, like many photosensitizers for photodynamic therapy (PDT), localizes to intracellular membranes, especially mitochondria. Pc 4-PDT photodamages Bcl-2 and Bcl-xL, antiapoptotic proteins interacting with the permeability transition pore complex that forms at contact sites between the inner and outer mitochondrial membranes. These complexes and the inner membrane are unique in containing the phospholipid cardiolipin. Nonyl-acridine orange (NAO) is a specific probe of cardiolipin. Here we show evidence for fluorescence resonance energy transfer from NAO to Pc 4, defining a binding site for the photosensitizer. This observation establishes an innovative tool for exploring the localization of other photosensitizers and additional fluorescent, mitochondrion-localizing drugs having appropriate spectral properties. 相似文献
30.
Lyytikäinen O Nuorti JP Halmesmäki E Carlson P Uotila J Vuento R Ranta T Sarkkinen H Ammälä M Kostiala A Järvenpää AL 《Emerging infectious diseases》2003,9(4):470-473
We analyzed surveillance data on group B streptococcus (GBS) infection in Finland from 1995 to 2000 and reviewed neonatal cases of early-onset GBS infection in selected hospitals in 1999 to 2000. From 1995 to 2000, 853 cases were reported (annual incidence 2.2-3.0/100,000 population). We found 32-38 neonatal cases of early-onset GBS disease per year (annual incidence 0.6-0.7/1,000 live births). In five hospitals, 35% of 26 neonatal cases of early-onset GBS infection had at least one risk factor: prolonged rupture of membranes, preterm delivery, or intrapartum fever. Five of eight mothers screened for GBS were colonized. In one case, disease developed despite intrapartum chemoprophylaxis. Although the incidence of early-onset GBS disease in Finland is relatively low, some geographic variation exists, and current prevention practices are suboptimal. Establishing national guidelines to prevent perinatal GBS is likely to reduce the incidence of the disease. 相似文献