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1.
The search for the genetic defects in constitutional diseases has so far been restricted to direct methods for the identification of genetic mutations in the patients' genome. Traditional methods such as karyotyping, FISH, mutation screening, positional cloning and CGH, have been complemented with newer methods including array-CGH and PCR-based approaches (MLPA, qPCR). These methods have revealed a high number of genetic or genomic aberrations that result in an altered expression or reduced functional activity of key proteins. For a significant percentage of patients with congenital disease however, the underlying cause has not been resolved strongly suggesting that yet other mechanisms could play important roles in their etiology. Alterations of the 'native' epigenetic imprint might constitute such a novel mechanism. Epigenetics, heritable changes that do not rely on the nucleotide sequence, has already been shown to play a determining role in embryonic development, X-inactivation, and cell differentiation in mammals. Recent progress in the development of techniques to study these processes on full genome scale has stimulated researchers to investigate the role of epigenetic modifications in cancer as well as in constitutional diseases. We will focus on mental impairment because of the growing evidence for the contribution of epigenetics in memory formation and cognition. Disturbance of the epigenetic profile due to direct alterations at genomic regions, or failure of the epigenetic machinery due to genetic mutations in one of its components, has been demonstrated in cognitive derangements in a number of neurological disorders now. It is therefore tempting to speculate that the cognitive deficit in a significant percentage of patients with unexplained mental retardation results from epigenetic modifications.  相似文献   

2.
《Trends in microbiology》2023,31(4):356-368
The vaginal microbiome (VMB) is critical to female reproductive health; however, the mechanisms associated with optimal and non-optimal states remain poorly understood due to the complex community structure and dynamic nature. Quantitative systems biology techniques applied to the VMB have improved understanding of community composition and function using primarily statistical methods. In contrast, fewer mechanistic models that use a priori knowledge of VMB features to develop predictive models have been implemented despite their use for microbiomes at other sites, including the gastrointestinal tract. Here, we explore systems biology approaches that have been applied in the VMB, highlighting successful techniques and discussing new directions that hold promise for improving understanding of health and disease.  相似文献   

3.
The techniques and principles of epidemiology, so successfully utilized in the study and control of communicable diseases, should be applied to other mass phenomena in the community.The local health officer should apply them in his “diagnosis” of the sicknesses of his organized community.Epidemiological methods have been used to study mental diseases as well as chronic diseases, and an experiment in using epidemiological methods on the county level to study psychosocial disorders has been carried out.The impact of psychosocial episodes on somatic diseases is now generally accepted and well documented. Individual practitioners of medicine are becoming more interested in the significance of social tensions on the health of their patients.Public health physicians, specialists in preventive medicine, are the best equipped by training and experience to take the leadership in the application of epidemiological methods to sociomedical problems and are in a unique position to assist their colleagues in the private practice of medicine in providing modern helpful and meaningful health protection to their patients.Organized medicine might well become more cognizant of the sociological changes taking place in the nation as they relate to health and assume the responsibility for aggressive leadership in the anticipation of and the solution of these problems.  相似文献   

4.
污染土壤微生物群落结构多样性及功能多样性测定方法   总被引:18,自引:0,他引:18  
陈承利  廖敏  曾路生 《生态学报》2006,26(10):3404-3412
土壤微生物在促进土壤质量和植物健康方面发挥着重要的作用,土壤微生物群落结构和组成的多样性及其变化在一定程度上反映了土壤质量.为了更好地了解土壤健康状况,非常有必要发展有效的方法来研究污染土壤微生物的多样性、分布以及行为等.回顾了近年来国内外污染土壤微生物群落结构多样性及功能多样性的测定方法,包括生物化学技术和分子生物学技术,现将它们的原理、优缺点、实用性及其发展动态作一阐述,同时指出结合这两种技术可为微生物群落分析提供一个更全面的、精确的方法.  相似文献   

5.
The aim of the study was to find out how EEG rhythmical patterns change with gradual changes of a degree of verbal and spatial thinking involved in the process of task solving. The obtained data allowed us to draw two principally new conclusions. 1. During performance of mixed tasks the spatial and verbal thinking do not mix, and their rhythmical signs are both present with their basic properties preserved. A mixed rhythmical pattern is thus a superposition of a spatial and a verbal pattern. 2. It is possible to introduce a "distance" between mental conditions as a measure of difference in the corresponding EEG power spectra. With such distances calculated, multidimensional scaling methods may be used to represent cognitive states as points on a plane. Cognitive states form constellations with shapes reasonably reflecting psychological properties of cognitive tasks. The results suggest the existence of a "cognitive space", whose structure may be revealed by objective electrophysiological methods.  相似文献   

6.
The needs of people with serious mental illnesses have dominated much of the debate on reforming community care. In this article Peter Campbell, who has used mental health services many times in the past, explains how the reforms could affect people like him. He welcomes the thinking behind the changes, particularly the idea that people who use community care should take part in planning services, but he warns that implementing the new philosophy might prove very difficult. Mr Campbell is secretary of a voluntary organisation for users of mental health services called Survivors Speak Out. The views he expresses here are his own, and do not necessarily reflect those of Survivors Speak Out.  相似文献   

7.
In this article we critically review the neural mechanisms of moral cognition that have recently been studied via electroencephalography (EEG). Such studies promise to shed new light on traditional moral questions by helping us to understand how effective moral cognition is embodied in the brain. It has been argued that conflicting normative ethical theories require different cognitive features and can, accordingly, in a broadly conceived naturalistic attempt, be associated with different brain processes that are rooted in different brain networks and regions. This potentially morally relevant brain activity has been empirically investigated through EEG-based studies on moral cognition. From neuroscientific evidence gathered in these studies, a variety of normative conclusions have been drawn and bioethical applications have been suggested. We discuss methodological and theoretical merits and demerits of the attempt to use EEG techniques in a morally significant way, point to legal challenges and policy implications, indicate the potential to reveal biomarkers of psychopathological conditions, and consider issues that might inform future bioethical work.  相似文献   

8.
After decades of effort by some of our brightest human and non-human minds, there is still little consensus on whether or not non-human animals understand anything about the unobservable mental states of other animals or even what it would mean for a non-verbal animal to understand the concept of a ‘mental state’. In the present paper, we confront four related and contentious questions head-on: (i) What exactly would it mean for a non-verbal organism to have an ‘understanding’ or a ‘representation’ of another animal''s mental state? (ii) What should (and should not) count as compelling empirical evidence that a non-verbal cognitive agent has a system for understanding or forming representations about mental states in a functionally adaptive manner? (iii) Why have the kind of experimental protocols that are currently in vogue failed to produce compelling evidence that non-human animals possess anything even remotely resembling a theory of mind? (iv) What kind of experiments could, at least in principle, provide compelling evidence for such a system in a non-verbal organism?  相似文献   

9.
Predicting a particular cognitive state from a specific pattern of fMRI voxel values is still a methodological challenge. Decoding brain activity is usually performed in highly controlled experimental paradigms characterized by a series of distinct states induced by a temporally constrained experimental design. In more realistic conditions, the number, sequence and duration of mental states are unpredictably generated by the individual, resulting in complex and imbalanced fMRI data sets. This study tests the classification of brain activity, acquired on 16 volunteers using fMRI, during mental imagery, a condition in which the number and duration of mental events were not externally imposed but self-generated. To deal with these issues, two classification techniques were considered (Support Vector Machines, SVM, and Gaussian Processes, GP), as well as different feature extraction methods (General Linear Model, GLM and SVM). These techniques were combined in order to identify the procedures leading to the highest accuracy measures. Our results showed that 12 data sets out of 16 could be significantly modeled by either SVM or GP. Model accuracies tended to be related to the degree of imbalance between classes and to task performance of the volunteers. We also conclude that the GP technique tends to be more robust than SVM to model unbalanced data sets.  相似文献   

10.
Locating and capturing food are suggested as significant selection pressures for the evolution of various cognitive abilities in mammals and birds. The hypothesis is proposed that aspects of food procuring behaviour should be strongly indicative of particular cognitive abilities.Experimental data concerning higher mental abilities in mammals and birds are reviewed. These data deal with self-recognition studies, rule-learning experiments, number concept, deceptive abilities, tool-use and observational learning.A Darwinian approach reveals: (1) the adaptiveness of particular abilities for particular niches, (2) that in complex foraging environments, increases in foraging efficiencies in animals should result from the evolution of particular cognitive abilities, (3) that phenomena such as convergent mental evolution should be expected to have taken place across taxonomic groups for species exploiting similar niches, (4) that divergence in mental ability should also have taken place where related species have exploited dissimilar niches.Experimental data of higher mental abilities in animals concur with a Darwinian explanation for the distribution of these cognitive abilities and no anomalies have been found.There are, as a consequence, significant implications for the welfare of animals subject to training when training methodology gives little or no consideration to the various mental abilities of species.  相似文献   

11.
R H Fisher  E M Meslin 《CMAJ》1990,142(1):23-26
Living wills allow patients to state their wish to die and not be kept alive through the use of medications, artificial means or "heroic" measures. They have been made legal documents in 38 states in the United States. Living wills permit advance expression of a patient''s wishes, promote effective communication and demonstrate respect for the patient as a person. Problems with legal recognition of such wills include the need for agreement on fundamental terms, possible restriction of patients'' rights, limitation of options in decision-making and possible negative effects on the physician-patient relationship. Before legislation is enacted, public and professional attitudes toward the care of terminally ill patients should be assessed. All health care professionals should receive better education in this area, and palliative care services should be made more widely available. Only if these measures fail should living wills be made legal documents in Canada.  相似文献   

12.
Decades of research conducted in Western, Educated, Industrialized, Rich, & Democratic (WEIRD) societies have led many scholars to conclude that the use of mental states in moral judgment is a human cognitive universal, perhaps an adaptive strategy for selecting optimal social partners from a large pool of candidates. However, recent work from a more diverse array of societies suggests there may be important variation in how much people rely on mental states, with people in some societies judging accidental harms just as harshly as intentional ones. To explain this variation, we develop and test a novel cultural evolutionary theory proposing that the intensity of kin-based institutions will favor less attention to mental states when judging moral violations. First, to better illuminate the historical distribution of the use of intentions in moral judgment, we code and analyze anthropological observations from the Human Area Relations Files. This analysis shows that notions of strict liability—wherein the role for mental states is reduced—were common across diverse societies around the globe. Then, by expanding an existing vignette-based experimental dataset containing observations from 321 people in a diverse sample of 10 societies, we show that the intensity of a society's kin-based institutions can explain a substantial portion of the population-level variation in people's reliance on intentions in three different kinds of moral judgments. Together, these lines of evidence suggest that people's use of mental states has coevolved culturally to fit their local kin-based institutions. We suggest that although reliance on mental states has likely been a feature of moral judgment in human communities over historical and evolutionary time, the relational fluidity and weak kin ties of today's WEIRD societies position these populations' psychology at the extreme end of the global and historical spectrum.  相似文献   

13.
14.
阿尔茨海默病(Alzheimer's disease,AD)是以记忆和其他高级认知功能下降为特征的神经退行性疾病.早期的神经影像学研究通常是探索AD患者局部脑区的结构和功能变化.随着多模态神经影像技术和人脑连接组学研究方法的发展,研究者已经能够考察AD患者脑结构和功能连接通路.采用这些方法,最近的研究已经发现,AD患者脑网络的连接强度、网络效率、模块化组织和核心脑区连接的下降,并发现这些变化与患者的记忆评分等密切相关.这些新方法和新技术的出现不仅提供了新颖的观点来解释AD病的脑区失连接病理生理机制,而且发现的AD异常脑连接模式可能作为敏感特征应用于AD早期辅助诊断的影像标记物研究.特别重要的是,研究表明,在AD患者脑神经网络出现的异常连接模式,在AD前期即轻度认知障碍期患者中也已出现,表明了将AD影像学研究的重点前移到AD前期这一可治疗阶段的重要性和迫切性.  相似文献   

15.
Social functioning depends on the ability to attribute and reason about the mental states of others – an ability known as theory of mind (ToM). Research in this field is limited by the use of tasks in which ceiling effects are ubiquitous, rendering them insensitive to individual differences in ToM ability and instances of subtle ToM impairment. Here, we present data from a new ToM task – the Short Story Task (SST) - intended to improve upon many aspects of existing ToM measures. More specifically, the SST was designed to: (a) assess the full range of individual differences in ToM ability without suffering from ceiling effects; (b) incorporate a range of mental states of differing complexity, including epistemic states, affective states, and intentions to be inferred from a first- and second-order level; (c) use ToM stimuli representative of real-world social interactions; (d) require participants to utilize social context when making mental state inferences; (e) exhibit adequate psychometric properties; and (f) be quick and easy to administer and score. In the task, participants read a short story and were asked questions that assessed explicit mental state reasoning, spontaneous mental state inference, and comprehension of the non-mental aspects of the story. Responses were scored according to a rubric that assigned greater points for accurate mental state attributions that included multiple characters’ mental states. Results demonstrate that the SST is sensitive to variation in ToM ability, can be accurately scored by multiple raters, and exhibits concurrent validity with other social cognitive tasks. The results support the effectiveness of this new measure of ToM in the study of social cognition. The findings are also consistent with studies demonstrating significant relationships among narrative transportation, ToM, and the reading of fiction. Together, the data indicate that reading fiction may be an avenue for improving ToM ability.  相似文献   

16.
The soft-bodied cephalopods including octopus, cuttlefish, and squid are broadly considered to be the most cognitively advanced group of invertebrates. Previous research has demonstrated that these large-brained molluscs possess a suite of cognitive attributes that are comparable to those found in some vertebrates, including highly developed perception, learning, and memory abilities. Cephalopods are also renowned for performing sophisticated feats of flexible behaviour, which have led to claims of complex cognition such as causal reasoning, future planning, and mental attribution. Hypotheses to explain why complex cognition might have emerged in cephalopods suggest that a combination of predation, foraging, and competitive pressures are likely to have driven cognitive complexity in this group of animals. Currently, it is difficult to gauge the extent to which cephalopod behaviours are underpinned by complex cognition because many of the recent claims are largely based on anecdotal evidence. In this review, we provide a general overview of cephalopod cognition with a particular focus on the cognitive attributes that are thought to be prerequisites for more complex cognitive abilities. We then discuss different types of behavioural flexibility exhibited by cephalopods and, using examples from other taxa, highlight that behavioural flexibility could be explained by putatively simpler mechanisms. Consequently, behavioural flexibility should not be used as evidence of complex cognition. Fortunately, the field of comparative cognition centres on designing methods to pinpoint the underlying mechanisms that drive behaviours. To illustrate the utility of the methods developed in comparative cognition research, we provide a series of experimental designs aimed at distinguishing between complex cognition and simpler alternative explanations. Finally, we discuss the advantages of using cephalopods to develop a more comprehensive reconstruction of cognitive evolution.  相似文献   

17.
The final text of the REACH legislation, that has recently been published by the European Parliament, and which will come into force in the middle of 2007, implies that results obtained from so-called 'suitable' in vitro methods could be used for testing. It is also stated that a 'suitable' test is one that has been deemed to be ready to enter a validation study - for example, according to criteria specified by ECVAM. It is argued that, because the wording of the legal text is too vague and imprecise, it is totally unsatisfactory, mainly because it seems to endorse the application of non-validated methods for regulatory risk assessment. While their use might be suitable for providing information for classification in a weight-of-evidence approach, setting safe dose levels should only ever be based on the use of data from a properly validated test method. This concern, and other problems raised by the final legislation, is discussed, and recommendations are made which could avoid the premature use of potentially unsuitable methods for risk assessment, whilst ensuring that potentially suitable tests can be used for this purpose, once they have been formally validated.  相似文献   

18.
Characterization of unfolded states, while critical to a complete understanding of protein folding, is inherently difficult due to structural heterogeneity and dynamic interchange between states. The growing body of work focusing on single molecule fluorescence techniques for the study of protein folding, also highlights their potential for studies of unfolded proteins. These methods can obtain conformational information about individual subpopulations of molecules in an ensemble, and measure dynamics without the need for synchronization. The studies highlighted here demonstrate the promise of these techniques for obtaining novel information about unfolded states in vitro and in more physiologically relevant milieu.  相似文献   

19.
Current efforts to improve the community-based care of psychiatric patients often include attempts to encourage the ambulatory treatment of acute psychosis by non-psychiatrists. New therapies and revisions of older methods now allow this to be done with many patients for whom, 15 years ago, state hospitalization would have been the first step in treatment, and often the last.Many techniques applicable to the ambulatory treatment of acute psychotic crises can be used effectively by non-psychiatrists. This review describes ambulatory treatment programs for the more commonly encountered acute psychoses. It emphasizes methods which have only recently become available and those which can be used effectively and safely by the non-specialist. With the skillfully combined use of pharmacotherapy, environmental modification, office psychotherapy, legal aids and community resources, the interested nonpsychiatrist can undertake the ambulatory treatment of many psychotic crises.  相似文献   

20.
At a conference organised by the Law Society, Mental Health Act Commission, and Institute of Psychiatry possible reform of mental health legislation in England and Wales was discussed. It was concluded that radical legal reform was required, and that the law should be designed specifically for provision of care in both hospital and the community. Reform should be based on principle rather than pragmatism, particularly the principle of reciprocity--patients'' civil liberties may not be removed for the purposes of treatment if resources for that treatment are inadequate. Protection of society from nuisance or even violence is insufficient reason for detention. Legal provision for compulsion of patients, whether in hospital or the community, must be matched by specific rights to treatment.  相似文献   

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