Irritable bowel syndrome: The role of psychosocial factors

The irritable bowel syndrome (IBS) is a very common disorder of intestinal function characterized by variable symptoms of abdominal pain, diarrhea, constipation and bloating. The spectrum of severity ranges from mild symptoms, not worthy of clinical attention, to intense and continuous symptoms associated with impaired health-related quality of life and high health care use. Psychosocial disturbance is commonly found among patients with irritable bowel, but until recently, its precise role in the disorder was uncertain. The data now suggest that irritable bowel is not a psychiatric disorder per se, but psychosocial factors including life stress, psychiatric comorbidity and abnormal illness behavior, among others, influence how the illness is experienced and acted upon. Patients with mild symptoms usually respond to education, reassurance, dietary modification and, when needed, antimotility agents. However, patients with more severe symptoms, who usually have greater psychosocial disturbance, will also require behavioral interventions, and possibly psychopharmacological agents. In sum, a graduated, multicomponent plan of care that includes dietary, behavioral and pharmacological treatments is recommended.     

Support networks and dementia

Based on data from a sample of 4500+ people aged 65+ living in the community (ie not in residential care) in Liverpool, this article presents data on the availability of kin and levels of contact with family, friends neighbours and community groups, and compares the distribution of support network types of those identified as cases of dementia with non-cases. It is shown that dementia sufferers are more likely to live with others and to have more contact with family members and less contact with friends, neighbours and community groups than non-sufferers. It is also shown that the distribution of network type is distinctively different for cases and non-cases and it is suggested that this reflects the greater ability of some types of network to support continued community residence in the face of the onset of dementia.     

神经网络分析方法用于心脏病诊断的研究

神经网络可以很好的拟合任意的非线性函数。我们从 QRS波群的高频三维频谱中提取出一些定量的特征参数 ,用神经网络的方法对这些参数进行有监督的学习训练 ,最终能在由这些特征参数张成的 m维空间中构建出一个 m维的曲面来区分病人和健康人的 QRS波群高频三维频谱 ,从而使得训练后的网络能基于 QRS波群的高频三维频谱自行诊断出病人和健康人     

脑健冲剂对AD模型大鼠行为学及线粒体结构影响的实验研究

目的：研究脑健冲剂对AD模型大鼠行为学及线粒体超微结构的影响。方法：采用D-半乳糖致衰老与β-淀粉样蛋白注射联合所致的AD大鼠模型，服用脑健冲剂，测试大鼠在迷宫中的学习及记忆能力和海马CAl区线粒体体密度、面数密度等形态学指标。结果：脑健冲剂能有效的改善AD模型大鼠的学习、记忆障碍，并能很好地改善线粒体结构的受损程度。结论：脑健冲剂对AD有较明显的治疗作用，为临床应用脑健冲剂治疗AD提供实验依据。     

Unsupervised fuzzy clustering analysis supports behavioral cutoff criteria in an animal model of posttraumatic stress disorder.

BACKGROUND: Unsupervised fuzzy clustering (UFC) analysis is a mathematical technique that groups together objects in the multidimensional feature space according to a specified similarity measurement, thereby yielding clusters of similar data points that can be represented by a set of prototypes or centroids. METHODS: Since clinical studies of mental disorders distinguish between affected and unaffected individuals, we designed an inclusion/exclusion criteria (cutoff behavioral criteria [CBC]) approach for animal behavioral studies. The effect of classifying the study population into clearly affected versus clearly unaffected individuals according to behaviors on two behavioral paradigms was statistically significant. RESULTS: Here the raw data from previous studies were subjected to UFC algorithms as a means of objectively testing the validity of the concept of the CBC for our experimental model. The first UFC algorithm yielded two clearly discrete clusters, found to consist almost exclusively of the exposed animals in the one and unexposed animals in the other. The second algorithm yielded three clusters corresponding to animals designated as clearly affected, partially affected, and clearly unaffected. The algorithm for physiological data in addition to behavioral data failed to elicit discrete clusters. CONCLUSIONS: The UFC analysis yielded data that support the conceptual contention of the CBC and lends additional validity to our previous behavioral studies.     

Cognitive behavioral treatment for young children with obsessive-compulsive disorder.

Obsessive-compulsive disorder (OCD) is a distressing and functionally impairing disorder that can emerge as early as age 4. Cognitive behavior therapy (CBT) for OCD in youth shows great promise for amelioration of symptoms and associated functional impairment. However, the empirical evidence base for the efficacy of CBT in youth has some significant limitations, particularly as related to treating the very young child with OCD. This report includes a quantitative review of existing child CBT studies to evaluate evidence for the efficacy of CBT for OCD. It identifies gaps in the literature that, when addressed, would enhance the understanding of effective treatment in pediatric OCD. Finally, it presents a proposed research agenda for addressing the unique concerns of the young child with OCD.     

Simulating realistic zero loop pedigrees using a bipartite Prufer code and graphical modelling.

Graph algorithms previously developed by the authors are adapted to simulate pedigrees similar to those used in genetic linkage studies which associate disease phenotypes with specific genomic locations. Pedigrees are chosen uniformly at random from the set of those with specified numbers of individuals and matings and which contain no loops. Summary statistics from pedigrees generated in this way can be used to check real pedigrees for anomalies due to biased sampling or phenotypic effects on the pedigree structure.     

Detection of electrocardiographic ‘left ventricular strain’ using neural nets

The use of artificial neural networks for classification of ST-T abnormalities of the electrocardiogram (ECG) was investigated. A training set of 356 lateral leads selected from 105 ECGs was visually classified as exhibiting one particular ST-T morphology (left ventricular (LV) strain) or not. Selected measurements, together with the classification, were fed as input to a three-layer software-based network during the learning process. The performance of the network was evaluated by comparing the results obtained from the network with conventional criteria, using two test sets. Set 1 comprised 63 lateral leads from 32 ECGs with ST-T changes showing atypical forms of LV strain. Set 2 consisted of 80 lateral leads from 20 ECGs containing normal and abnormal T-waves. For set 1, the network outperformed conventional criteria, having a higher sensitivity (96 per cent against 85 per cent) and specificity (67 per cent against 50 per cent). With test set 2, both network and conventional criteria were 100 per cent sensitive and 100 per cent specific. For sets 1 and 2 combined, the network had a higher overall sensitivity (97 per cent agaisst 89 per cent) and specificity (88 per cent against 82 per cent). The results suggest that neural networks may be useful in selected areas of electrocardiography, but care is required when selecting patterns for use in the training process.     

Some behavioral effects of repeated d-amphetamine administrations

Effects of daily administrations of d-amphetamine were studied on key peck responses of pigeons maintained under a multiple fixed-interval 2-min, fixed-ratio 30-responseschedule. Under the fixed-interval schedule, a pause was followed by a transition to increasing rates of responding until food presentation. Under the fixed-ratio schedule, higher sustained rates of responding were maintained. Low to intermediate doses (0.3-1.0 mg/kg) of d-amphetamine changed the temporal patterns and occasionally increased rates of responding under the fixed-interval schedule. Higher doses decreased rates of responding under bothschedules. With daily injections of 1.0 mg/kg d-amphetamine prior to experimental sessions, the effects of this dose on rates and patterns of responding were attenuated, and d-anphetamine dose-effect curves were shifted to the right, primarily under the fixed-ratio schedule. Similar results were obtained with daily presession injections of 5.6 mg/kg d-amphetamine in a second group of pigeons, except that rates of responding under both schedules were decreased by this daily dose, and did not return completely to control values with repeated injections. In a third group of pigeons, 1.0 mg/kg d-amphetamine administered daily, after experimental sessions, did not alter dose-effect functions for d-amphetamine. In a second experiment, pigeons were trained to peck one response key when given 1.0 mg/kg d-amphetamine and a different key when given presession water injections. Increasing doses of d-amphetamine produced incresing percentages of d-amphetamine-key responses. Repeated administration of 5.6 mg/kg d-amphetamine shifted these dose-effect functions to the right one-half log unit. Results suggested that decreases in reinforcement frequency are not a necessary condition for the development of behavioral tolerance to d-amphetamine.     

微晶蜡非催化氧化反应的神经网络模型

对微晶蜡进行了非催化空气氧化，并利用人工神经网络将氧化微晶蜡的酸值、酯值及微晶蜡的氧化条件（反应温度、空气流量和反应时间）进行关联，建立了微晶蜡非催化氧化的酸值、酯值的神经网络模型，并用该模型预测了反应条件对微晶蜡氧化反应过程的影响。结果表明，该模型不但具有较高的计算精度，而且具有满意的预测能力。