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PubMed2002

Changes in cognitive functioning following comprehensive treatment for first episode patients with schizophrenia spectrum disorders.

The course of cognitive functioning over a 1-year period was examined among a community cohort of individuals presenting with first episode schizophrenia spectrum psychosis. Data were obtained for 83 outpatients at entry to an early intervention program and 12 months later on the National Adult Reading Test, Wechsler Adult Intelligence Scales-Third Edition, Wechsler Memory Scales-Third Edition, Paced Auditory Serial Addition Task, Wisconsin Card Sorting Test, Stroop Colour and Word Test, Trail Making Test, Continuous Performance Task and Thurstone Word Fluency Test. Paired sample t-tests indicated significant and positive changes in verbal and non-verbal intelligence, auditory and visual memory, working memory and some aspects of executive functioning. Processing speed also improved though remained an area of relative weakness for this sample. Findings indicated generally average performance at both assessment periods. Neither gender nor duration of untreated psychosis were related to the degree of change in cognitive functioning for this sample. The implications of these findings and the impact of early intervention with this population are discussed.

Adult↗

PubMed2005

Oxygen indicators and intelligent inks for packaging food.

The detection of oxygen using optical sensors is of increasing interest, especially in modified atmosphere food packaging (MAP), in which the package, usually containing food, is flushed with a gas, such as carbon dioxide or nitrogen. This tutorial review examines the ideal properties of an oxygen optical sensor for MAP and compares them with those developed to date, including the most recent advances. The basic technologies underpinning the different indicator types are described, examples given and their potential for application in MAP assessed. This tutorial review should be of interest to the MAP industry and researchers in optical sensors and oxygen sensing.

Colorimetry↗

PubMed1994

Knowledge-based system for the automated solid-phase extraction of basic drugs from plasma coupled with their liquid chromatographic determination. Application to the biodetermination of beta-receptor blocking agents.

Techniques for the preparation of biological samples are often based nowadays on solid-phase extraction (SPE). The different SPE steps can be performed automatically on disposable extraction cartridges (DECs) by means of a sample processor. A knowledge-based system was developed to facilitate the development of fully automated methods for the solid-phase extraction of relatively hydrophobic basic drugs from plasma, coupled with their determination by high-performance liquid chromatography (HPLC). The DEC filled with 50 mg of cyanopropyl-bonded silica phase is first conditioned with methanol and buffer solution (pH 7.4). After sample application, the DEC sorbent is washed with the same buffer. The analytes are then desorbed with an appropriate eluent and the eluate is finally diluted with the same buffer as used in the HPLC mobile phase before injection. Under these conditions, only three variables are still to be optimized: the composition and volume of the elution solvent and the volume of buffer to be added to the eluate. On the basis of this general strategy, a decision tree providing information about suggested starting conditions and guidelines for the optimization of the three variables was developed and implemented by use of a hypermedia software. This didactic expert system was evaluated using several beta-receptor blocking agents as model compounds and the operating conditions obtained for the automated SPE of these compounds are presented. A method for the determination of propranolol in plasma using the SPE conditions deduced from the knowledge-based system was validated. The absolute recovery of propranolol is ca. 93% and the limit of detection is 1.3 ng ml-1. The mean within-day and between-day reproducibilities are 2.3 and 3.6%, respectively.

Adrenergic beta-Antagonists↗

PubMed1993

Guaranteeing real-time response with limited resources.

Unanticipated problems detected by patient-monitoring systems may sometimes require real-time response in order to provide high-quality care and avoid catastrophic outcomes. In this paper, we present an approach for guaranteeing a response to such events by a monitoring agent even in situations where we have limited problem-solving resources. We show that an action-based hierarchy can accomplish this goal. We also analyze the performance of this hierarchy under varying resource availability and discuss decision-theoretic approaches to enable us to best structure such a hierarchy. We also describe an implementation of these ideas, called ReAct, in the BB1 architecture. All the ideas are illustrated with examples from the surgical intensive care unit (SICU).

Algorithms↗

PubMed2006

Stability and color changes of thermally treated betanin, phyllocactin, and hylocerenin solutions.

Thermal degradation of betanin, phyllocactin (malonyl-betanin), and hylocerenin (3' '-hydroxy-3' '-methyl-glutaryl-betanin) solutions isolated from purple pitaya (Hylocereus polyrhizus [Weber] Britton and Rose) was monitored by spectrophotometric and high-performance liquid chromatography-diode array detection (HPLC-DAD) analyses. For betanin and phyllocactin solutions, the color shift upon thermal treatment was found to be nearly identical, while hylocerenin samples exhibited an intelligibly higher chromatic steadiness. Betanin proved to be the most stable individual pigment structure, while the enhanced tinctorial stability of the integral phyllocactin and especially hylocerenin solutions was due to the formation of red degradation products exhibiting improved color retention as opposed to their respective genuine pigments. Individual structure-related stability characteristics can exclusively be assessed by HPLC-DAD analyses and may not be noticed by mere spectrophotometric assessment of color and tinctorial strength.

Betacyanins↗

PubMed1980

A comparison of cognitive impairment due to benzodiazepines and to narcotics.

In an attempt to determine the source of cognitive impairment in 106 consecutively admitted patients at the Johns Hopkins Chronic Pain Treatment Center, EEG, the Wechsler Adult Intelligence Scale, Memory Quotient, and Bender Gestalt tests were administered. Patients receiving benzodiazepines alone demonstrated alterations in cognitive functioning and EEG evidence of a sedative effect. Patients receiving narcotics alone and a group of patients not receiving medication did not show signs of cognitive impairment. The effects of benzodiazepines on sleep and perception of chronic pain, in combination with the cortical changes that they produce, imply that these drugs should not be used in most patients with chronic pain.

Adult↗

PubMed2003

PNA FISH: an intelligent stain for rapid diagnosis of infectious diseases.

Fluorescence in situ hybridization using peptide nucleic acid probes (PNA FISH) is a novel diagnostic technique combining the simplicity of traditional staining procedures with the unique performance of PNA probes to provide rapid and accurate diagnosis of infectious diseases; a feature that makes PNA FISH well suited for routine application and enables clinical microbiology laboratories to report important information for patient therapy within a time frame not possible using classic biochemical methods. Having transitioned from an academic curiosity into an advanced diagnostic tool, PNA probes are now debuting on the infectious disease stage, representing the new generation of therapy-directing diagnostics.

Anti-Infective Agents↗

PubMed1993

Positron-emission tomographic localization of abnormalities of brain metabolism in patients with minimal hepatic encephalopathy.

Many patients with compensated cirrhosis without overt hepatic encephalopathy have deficits in visual-spatial perception, a condition we call minimal hepatic encephalopathy. Five patients with alcohol-induced cirrhosis and nine control subjects underwent positron-emission tomographic imaging of the brain with 18F-fluorodeoxyglucose. Patients also underwent neuropsychological and clinical chemistry tests. The patients had mild arterial hyperammonemia (62 +/- 13 mumol/L, range = 11 to 35 mumol/L) and other abnormalities typical of patients with cirrhosis. The patients' mean percentile scores on the digit symbol and block design subtests, from the Wechsler Adult Intelligence Scale (revised), and Purdue pegboard test were 11 +/- 7, 24 +/- 7 and 7 +/- 8 (right hand). Tests of vocabulary, memory, and new learning were normal. The technique of statistical parametric mapping was used to identify regions where cerebral 18F-fluorodeoxyglucose uptake and metabolism were abnormal. We noted significant reductions in the cingulate gyrus, a center mediating attention, target analysis and response formulation and significant increases in visual associative regions subserving motion and color perception and object orientation. We suggest that minimal hepatic encephalopathy is due to a deficit in the detection and formulation of responses to visual stimuli, a function of the cingulate, which is a part of the anterior attentional system of the brain. Increases in 18F-fluorodeoxyglucose metabolism may be compensatory. These studies show that brain regions differ in their sensitivity to the agents that cause hepatic encephalopathy and that positron-emission tomography is useful in studying the pathophysiology of this disorder.

Adult↗

PubMed1995

[Spontaneous course of depression].

The study of the spontaneous course of depressions nowadays comes up against a number of obstacles. The most important of these is the necessity of using untreated cases, which virtually forces the contemporary researcher to refer to studies performed in the pretherapeutic era, if conclusions are not be drawn only from classical descriptions. Unfortunately, these studies are marked by the absence of strict diagnostic criteria, the heterogeneity of patients included in them, the lack of preciseness of evaluations and the primitive statistical methods used. They are concerned essentially with the duration of depressive phases and the factors which influence it. Among these latter are regularly found age, sex, the number of episodes, the duration of the preceding symptom-free interval, the severity and semiology of the attack, heredity, mode of onset, level of intelligence, the presence or absence of associated pathology and the presence or absence of hospitalisation. Chronicization of depression and the factors concerned with it have also been the object of several studies. A small number of investigations compare the course of the illness in untreated populations. The study of the spontaneous course of depression evidences the necessity of having consensus definitions, and may serve as a basis for a better comprehension of the process of cure and of the real impact of therapies designed to treat depression.

Adult↗

PubMed1993

Strategies for the prevention of environmental neurotoxic illness.

Toxic chemicals in the environment can cause a wide range of neurological disease. High-dose exposures to environmental neurotoxicants have produced encephalopathy in children ingesting chips of lead-based paint, blindness in persons who ingested methanol, blindness and ataxia in persons who consumed organic mercury, spinal cord degeneration and peripheral neuropathy in persons exposed to tri-ortho-cresyl phosphate (TOCP), and Parkinsonism in persons exposed to MPTP or to manganese. Environmental neurotoxicants have also been shown to produce a wide range of subclinical neurotoxic effects, including reduction in intelligence, impairment in reasoning ability, shortening of attention span, and alternation of behavior. The first step in the prevention of environmental neurotoxicity is to test chemicals for their toxic potential. More than 70,000 chemicals are currently in commerce. However, except for pharmaceuticals, fewer than 10% of these chemicals have been tested for neurotoxicity. A logical approach to neurotoxicologic assessment of chemical substances will build on and extend currently available test systems. It will have a tiered structure. The first or screening tier will consist of tests to measure obvious structural and functional changes, often a functional observational battery. Subsequent levels of testing will be guided by the results of initial screening. Toxicologic testing must be supplemented by epidemiologic surveillance of populations exposed to known and suspect neurotoxicants. Screening programs in these populations designed to detect excessive absorption of a neurotoxic agent or subclinical neurological dysfunction can be useful in identifying affected individuals before severe disability occurs.

Biomarkers↗

PubMedDate not supplied

Interaction of maternal smoking and other in-pregnancy exposures: analytic considerations.

The teratogenicity of cigarette smoke has been widely researched over the past two decades, in large part due to the work of Fried et al. The current study was designed to investigate some methodological issues surrounding the investigation of the effects of maternal smoking along with other potentially teratogenic agents in pregnancy. Specifically, maternal smoking was investigated both as a covariate and with regards to its main and interactive effects on child IQ in a prospectively ascertained sample of children whose mothers reported pregnancy exposures to four classes of agents: varicella virus infection (VC), selective serotonin reuptake inhibitors (SSRIs), antiepileptic drugs (AEDs) and benzodiazepines (BZDs). Children were also included whose mothers were not exposed to one of these four agents during pregnancy. The goal of this study was not to examine the behavioral teratogenic potential of these agents or of maternal smoking. Rather, our goal was to illustrate some methodological issues in addressing the combined effects of these agents in behavioral teratology. In the analyses of all four exposures, when smoking was considered as a covariate, it was either a significant or marginally significant covariate and the exposure of interest was not significantly related to a change in IQ score. However, when maternal smoking was considered as a factor in the analyses, four different patterns emerged illustrating the potential importance of properly addressing maternal smoking in the analysis of other potential behavioral teratogens.

Adolescent↗

PubMed2002

[How is an information program for depressed patients perceived?].

BACKGROUND: "Laere og Støtte" (LOS) is the Norwegian version of an information programme (Rhythms) developed in the United States for patients with depression who are treated with selective serotonin reuptake inhibitors (SSRI) in general practice. The patients receive seven booklets by mail over a period of seven months. MATERIAL AND METHODS: In order to examine customer satisfaction we sent a questionnaire to 920 patients that had subscribed to the information programme. We got valid information from 413 (44.8%) of the patients. RESULTS: Patients were generally quite satisfied with the information, its pacing and intelligibility. 281 (72.2%) were very satisfied or satisfied with the content, and 264 (66.2%) reported that the programme had motivated them to continue medication. We found minimal differences in responses as to gender, marital status, and former depression. INTERPRETATION: The programme was considered helpful by the majority of the respondents as a supplement to the drug treatment of depression in general practice. A weakness of the study is the low response rate; we presume a bias toward those who are satisfied with the programme.

Adolescent↗

PubMedDate not supplied

[Subjective and objective assessment of memory functions in patients with schizophrenia treated with olanzapine].

Schizophrenic patients often complain of intellectual functioning impairment. The aim of this survey was to define the subjective memory loss by means of objective tests. The tests were carried out in three steps: before the admission to the clinic, after 6 weeks of hospitalisation, and after approximately 12 months from the beginning of the olanzapine treatment, 36 patients were examined (9 female, 27 male) aged 20-53 (X = 25.4). The following tests were applied: PANSS, Memory Questionnaire (Squire, Zouzounis 1988), subscales: Digit span and Similarities of the Wechsler Intelligence Scale, subtest for Long-term memory of the Choynowski's Memory Scale, Diagnosis of Brain Damages (Weidlich, Lamberti), Clock Completion Test, Decroly Box. The subjective assessment of memory functioning improved during the treatment with olanzapine. Before the hospitalisation and after 6 weeks of treatment patients' memory complaints were associated with the visuospatial memory. After 12 month of the olanzapine therapy the memory complaints were associated with audioverbal memory. Age, level of education and objective intensity of psychopathological symptoms did not influence patients' subjective assessment of memory functioning.

Adult↗

PubMed1997

[Isolated retrograde amnesia following viral encephalitis].

We describe a patient who presented with isolated retrograde amnesia of 2-year duration after recovery from viral encephalitis. The patient was a 29-year-old right-handed male dentist and was admitted to our hospital with a complaint of generalized convulsion. Cerebrospinal fluid (CSF) showed mononuclear pleocytosis. Neuroradiological examinations (X-ray CT, MRI and 123I-IMP SPECT) revealed no significant abnormality. Immunological method showed no specific increase of viral antibody titers. However, with a tentative diagnosis of viral encephalitis, administration of acyclovir was started. After 3 weeks he became comprehensive, and several kinds of neuropsychological tests were performed. His intelligence and immediate memory were normal, and his procedural memory of dentist was intact. On the other hand, he could not recall any information about events, both personal and public, occurred within 2 years before the onset of present illness. His autobiographical memory disorder was also demonstrated using a series of weekly comic. In isolated retrograde amnesia following viral encephalitis like this case, memory of relatively short time duration, acquired prior to the onset of present illness, tend to be disturbed.

Acyclovir↗

PubMed1975

Psychological eff-cts of halothane and isoflurane anesthesia.

Psychological effects of halothane (16 subjects) and isoflurane (24 subjects) anesthesia on healthy young men were assessed prior to and 2,3,4,6,8, and 30 days after anesthesia. The results with each agent were compared with each other and with the results for 41 unanesthetized controls. Both agents altered psychological function. Changes in function were greatest 2 days after anesthesia; function had returned to near preanesthesia values 8 days after anesthesia. Only slight symptom and mood effects and no intellectual effect attributable to anesthesia remained 30 days after anesthesia. Halothane produced greater negative effects on moodds and symptoms and tended to produce greater negative effects on intellectural function than did isoflurane. The differences between the two anesthetics are consistent with differences in their solubilities and metabolism.

Adult↗

PubMed1981

Schwartz-Jampel syndrome: a case report. Stimulatory effect of calcium and A23187 calcium ionophore for protein synthesis in muscle cell cultures.

This report describes a 3-year-old male patient with dwarfism, generalized muscular hypertrophy, stiffness, myotonia, multiple skeletal deformities and normal intelligence. Serum creatine kinase was twice elevated. EMG showed 'dive bomber' discharges and muscle biopsy revealed mild to moderate myopathic changes with variability in fiber size and 'moth-eaten' fibers. Multiple muscle cell cultures showed significantly lower values of total protein synthesis as determined by (3H)-leucine incorporation. The addition of calcium and/or A23187 calcium ionophore to cultures significantly stimulated total protein synthesis in contrast to the lack of effect of these drugs in control cultures. These findings suggest a dysfunction of muscle sarcolemma in Schwartz-Jampel syndrome.

Abnormalities, Multiple↗

PubMed2006

Simulating the hallmarks of cancer.

Cancer can be viewed as the loss of cooperative cell behaviors that normally facilitate multicellularity, including the formation of tissues and organs. Hanahan and Weinberg describe the phenotypic differences between healthy and cancerous cells in an article titled "The Hallmarks of Cancer" (Cell, 100, 57-70, 2000). Here the authors propose six phenotypic changes at the cellular level as the essential hallmarks of cancer. They investigate the dynamics and interactions of these hallmarks in a model known as CancerSim. They describe how CancerSim implements the hallmarks in an agent-based simulation which can help test the hypotheses put forth by Hanahan and Weinberg. Experiments with CancerSim are described that study the interactions of cell phenotype alterations, and in particular, the likely sequences of precancerous mutations, known as pathways. The experiments show that sequencing is an important factor in tumorigenesis, as some mutations have preconditions--they are selectively advantageous only in combination with other mutations. CancerSim enables a modeler to study the dynamics of a developing tumor and simulate how progression can be altered by tuning model parameters.

Apoptosis↗

PubMed1996

Collapsing a coevolutionary process into a computable function.

It is shown how the entire dynamics of a class of evolutionary systems can be used to perform a computation. The argument is constructive by presenting a Turing-machine-based set-up implemented in Enact, an artificial-life world embedded in a family of cellular automata; in this system, a population of agents move about in a two-dimensional space, interacting with their environment, reproducing and undergoing developmental and coevolutionary processes. As a byproduct, the paper also serves to characterise the main model of computation underlying Enact. This model is essentially parallel, and relies upon the machinery defined by the artificial-life processes. According to the model, a particular computation is considered to have been performed, if and only if, for some initial population and environmental configuration, at least one agent has developed into a state configuration that is insensitive to any further environmental interactions; in this situation, if the computation involved is a function, this individual has the result. If the population ever vanishes, or if the environment becomes short of the resources needed for development, the cellular space has to be re-initialized, and the process iterated. The presentation relies on the implementation of a function that recognises a particular context-free language. Implications of the model of computation are then discussed, in particular the model of coupled computations suggested by it.

Algorithms↗