Prediction of attack frequency in migraine treatment.

Usually limited information about the frequency of migraine episodes is derived from acute migraine trials. However, the design of some studies is such that they also provide relevant information about the attack frequency without the bias associated with patient expectations of treatment effect between attacks during prophylaxis trials. Using clinical data from repeated migraine attacks treated with placebo, naratriptan 2.

Modeling short-range stiffness of feline lower hindlimb muscles.

The short-range stiffness (SRS) of skeletal muscles is a critical property for understanding muscle contributions to limb stability, since it represents a muscle's capacity to resist external perturbations before reflexes or voluntary actions can intervene. A number of studies have demonstrated that a simple model, consisting of a force-dependent active stiffness connected in series with a constant passive stiffness, is sufficient to characterize the SRS of individual muscles over the entire range of obtainable forces. The purpose of this study was to determine if such a model could be used to characterize the SRS-force relationship in a number of architecturally distinct muscles.

Children's knowledge of the earth: a new methodological and statistical approach.

In the field of children's knowledge of the earth, much debate has concerned the question of whether children's naive knowledge-that is, their knowledge before they acquire the standard scientific theory-is coherent (i.e., theory-like) or fragmented.

Are skeletal muscles independent actuators? Force transmission from soleus muscle in the cat.

It is unclear if skeletal muscles act mechanically as independent actuators. The purpose of the present study was to investigate force transmission from soleus (SO) muscle for physiological lengths as well as relative positions in the intact cat hindlimb. We hypothesized that force transmission from SO fibers will be affected by length changes of its two-joint synergists.

[Metabolic encephalopathy can be a potentially life-threatening complication from valproic acid].

In two female patients of 62 and 81 years old, a metabolic encephalopathy was diagnosed which was ascribed to the use of valproic acid. Both had elevated ammonia levels in arterial blood, without hepatic failure. The first patient eventually became comatose and required artificial ventilation.

Evaluation of the Premi Test Salmonella, a commercial low-density DNA microarray system intended for routine identification and typing of Salmonella enterica.

A new commercial system based on genetic profiling and aimed at identifying Salmonella enterica serovars was evaluated by comparing its performance with classical serotyping on 443 strains. Within 62 serovars represented, 60 gave unique genetic profiles while 2 were undistinguishable. Results were obtained within 8 h, were reproducible and clear-cut.

Relevance of absorption rate and lag time to the onset of action in migraine.

Objective: The objective of this analysis was to simulate the performance of oral triptan formulations with varying absorption characteristics and their impact on the onset and magnitude of the antimigraine effect using a Markov model for migraine attacks.

Analysis: Sumatriptan pharmacokinetic data were obtained from clinical pharmacology studies in which marketed solid formulations were administered. Based on a population pharmacokinetic model, mean concentration-time profiles were generated by varying the absorption rate constant and lag time.

Step by step development of clinical care pathways for older cancer patients: necessary or desirable?

Medical and nursing staff in oncology for older cancer patients are confronted with a range of problems including co-morbidity, poly-pharmacy, cognitive impairments, emotional problems, functional limitations, sensory impairment and a lack of social support. Comprehensive geriatric assessment identifies many of the existing problems and can be used to estimate life expectancy and tolerance of treatment. However, health care providers have to interpret and apply the medical and nursing information and must deal with specific problems and care needs throughout the continuum of cancer care.

Comprehensive geriatric assessment and its clinical impact in oncology.

Comprehensive geriatric assessment (CGA) is a process that consists of a multidimensional data-search and a process of analyzing and linking patient characteristics creating an individualized intervention-plan, carried out by a multidisciplinary team. In general, the positive health care effects of CGA are established, but in oncology both CGA and the presence of geriatric syndromes still have to be implemented to tailor oncological therapies to the needs of elderly cancer patients. In this paper the conceptualization of geriatric syndromes, their relationship to CGA and results of clinical studies using CGA in oncology are summarized.

Comorbidity in older surgical cancer patients: influence on patient care and outcome.

Evidence is scarce about the influence of comorbidity on outcome of surgery, whereas this information is highly relevant for estimating the surgical risk of cancer patients, and for optimising pre-, peri- and postoperative care. In this paper, the prognostic role of increasing age and comorbid conditions in patients diagnosed with stage I-III colorectal, stage I-II NSCLC or stage I-III breast cancer between 1995 and 2004 in the southern part of the Netherlands is summarised. Almost all patients with stage I-III colon cancer or rectal cancer underwent surgery regardless of age or comorbidity.

Recent oceanic long-distance dispersal and divergence in the amphi-Atlantic rain forest genus Renealmia L.f. (Zingiberaceae).

Renealmia L.f. (Zingiberaceae) is one of the few tropical plant genera with numerous species in both Africa and South America but not in Asia.

An EZ-diffusion model for response time and accuracy.

The EZ-diffusion model for two-choice response time tasks takes mean response time, the variance of response time, and response accuracy as inputs. The model transforms these data via three simple equations to produce unique values for the quality of information, response conservativeness, and nondecision time. This transformation of observed data in terms of unobserved variables addresses the speed-accuracy trade-off and allows an unambiguous quantification of performance differences in two-choice response time tasks.

Nonnormality and divergence in posttreatment alcohol use: reexamining the Project MATCH data "another way.".

Alcohol lapses are the modal outcome following treatment for alcohol use disorders, yet many alcohol researchers have encountered limited success in the prediction and prevention of relapse. One hypothesis is that lapses are unpredictable, but another possibility is the complexity of the relapse process is not captured by traditional statistical methods. Data from Project Matching Alcohol Treatments to Client Heterogeneity (Project MATCH), a multisite alcohol treatment study, were reanalyzed with 2 statistical methodologies: catastrophe and 2-part growth mixture modeling.

The effects of self-reinnervation of cat medial and lateral gastrocnemius muscles on hindlimb kinematics in slope walking.

The aim of this study was to investigate the effects of self-reinnervation of the medial (MG) and lateral gastrocnemius (LG) muscles on joint kinematics of the whole hindlimb during overground walking on surfaces of varying slope in the cat. Hindlimb kinematics were assessed (1) with little or no activity in MG and LG (short-term effects of self-reinnervation), and (2) after motor function of these muscles was presumably recovered but their proprioceptive feedback permanently disrupted (long-term effects of self-reinnervation). The stance phase was examined in three walking conditions: downslope (-50%, i.

Analysis of responses in migraine modelling using hidden Markov models.

Markov-type models have been used in the analysis of disease progression. Although standard errors of model parameters are usually estimated, available software often does not permit the construction of confidence intervals around predictions of the dependent or response variable. A method is presented to calculate means and confidence intervals of model-predicted responses in time governed by a non-homogeneous hidden Markov model in continuous time.

Towards better computational models of the balance scale task: a reply to Shultz and Takane.

In contrast to Shultz and Takane [Shultz, T.R., & Takane, Y.

The effects of time pressure on chess skill: an investigation into fast and slow processes underlying expert performance.

The ability to play chess is generally assumed to depend on two types of processes: slow processes such as search, and fast processes such as pattern recognition. It has been argued that an increase in time pressure during a game selectively hinders the ability to engage in slow processes. Here we study the effect of time pressure on expert chess performance in order to test the hypothesis that compared to weak players, strong players depend relatively heavily on fast processes.

Photoisomerization of azobenzene derivatives in nanostructured silica.

A series of derivatized azobenzene molecules are synthesized such that one of the phenyl groups can be chemically bonded to mesostructured silica and the other, derivatized with dendrons, is free to undergo large-amplitude light-driven motion. The silica frameworks on which the motion takes place are either 150 nm thick films containing ordered hexagonal arrays of tubes (inner diameter about 2 nm) containing the bonded azobenzenes, or particles (about 500 nm in diameter) containing the same ordered arrays of functionalized tubes. The photoisomerization yields and the rate constants for the thermal cis to trans back-reaction of the azobenzenes in the tubes are measured and compared to those of the molecules in solution.

Photoisomerization of disperse red 1 studied with transient absorption spectroscopy and quantum chemical calculations.

The photoisomerization of the push-pull substituted azo dye Disperse Red 1 is studied using femtosecond time-resolved absorption spectroscopy and other spectroscopic and computational techniques. In comparison with azobenzene, the pipi* state is more stabilized by the effects of push-pull substitution than the npi* state, but the latter is probably still the lowest in energy. This conclusion is based on the kinetics, anisotropy of the excited state absorption spectrum, the spectra of the ground states, and quantum chemical calculations.

A model-based approach to treatment comparison in acute migraine.

Aims: Currently, direct comparisons between 5-HT(1B/d) receptor agonists are used to assess differences and similarities in antimigraine response. Such comparisons depend on the selected sampling time and do not allow evaluation of entire response profiles. A thorough evaluation of drug properties requires that the time course of the response be taken into account.

A dynamical model of general intelligence: the positive manifold of intelligence by mutualism.

Scores on cognitive tasks used in intelligence tests correlate positively with each other, that is, they display a positive manifold of correlations. The positive manifold is often explained by positing a dominant latent variable, the g factor, associated with a single quantitative cognitive or biological process or capacity. In this article, a new explanation of the positive manifold based on a dynamical model is proposed, in which reciprocal causation or mutualism plays a central role.

Antibiotic resistance, integrons and Salmonella genomic island 1 among non-typhoidal Salmonella serovars in The Netherlands.

The objective of this study was to investigate the antimicrobial resistance patterns, integron characteristics and gene cassettes as well as the presence of Salmonella genomic island 1 (SGI1) in non-typhoidal Salmonella (NTS) isolates from human and animal origin. Epidemiologically unrelated Dutch NTS strains (n=237) originating from food-producing animals and human cases of salmonellosis were tested for their susceptibility to 15 antimicrobial agents. Resistance to 14 of these antimicrobials, including the third-generation cephalosporins, was detected.

Re-thinking stages of cognitive development: an appraisal of connectionist models of the balance scale task.

The present paper re-appraises connectionist attempts to explain how human cognitive development appears to progress through a series of sequential stages. Models of performance on the Piagetian balance scale task are the focus of attention. Limitations of these models are discussed and replications and extensions to the work are provided via the Cascade-Correlation algorithm.

Prediction of headache response in migraine treatment.

Triptans are efficacious for the acute treatment of migraine attacks. Yet, defining a concentration-effect relation for these compounds is difficult as the dynamics of the migraine attack are not thoroughly understood. The objective of this investigation was to develop a disease model to predict measures of headache in randomized placebo-controlled clinical trials investigating oral sumatriptan as a paradigm compound.