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PubMed2001

Ecstasy (MDMA): are the psychological problems associated with its use reversed by prolonged abstinence?

RATIONALE: Chronic, regular recreational use of ecstasy (MDMA) is associated with psychopathology, elevated behavioural impulsivity and persistent impairment of memory performance. OBJECTIVE: The aim of the present study was to investigate which of these sequelae persist after at least 6 months of abstinence from ecstasy. METHODS: Four groups of participants were compared: 18 current regular recreational ecstasy users, 15 ex-regular ecstasy users who had abstained from using the drug for an average of 2 years, 16 polydrug users who had never taken ecstasy and 15 drug-naive controls. RESULTS: There were no significant group differences in age, education level, or pre-morbid intelligence and, generally, the use of illicit drugs other than ecstasy was not significantly different among the three drug-using groups. Both current and ex-ecstasy users exhibited elevated psychopathology and behavioural impulsivity compared with polydrug users and drug-naive controls, but current ecstasy users exhibited a broader range of psychopathology than ex-users. Both groups of ecstasy users also exhibited impaired working memory and verbal recall performance compared with drug-naive controls, but only ex-users exhibited impaired verbal recall relative to polydrug users. Regression analysis indicated that psychopathology was primarily predicted by the extent of previous consumption of cannabis rather than ecstasy, whereas the majority of the cognitive deficits were only predicted by the extent of previous ecstasy use. CONCLUSIONS: Selective impairments of neuropsychological performance associated with regular ecstasy use are not reversed by prolonged abstinence. This is consistent with evidence that ecstasy has potent and selective neurotoxic effects on brain serotonergic systems in humans.

Adult↗

PubMed2006

Decoding non-unique oligonucleotide hybridization experiments of targets related by a phylogenetic tree.

MOTIVATION: The reliable identification of presence or absence of biological agents ("targets"), such as viruses or bacteria, is crucial for many applications from health care to biodiversity. If genomic sequences of targets are known, hybridization reactions between oligonucleotide probes and targets performed on suitable DNA microarrays will allow to infer presence or absence from the observed pattern of hybridization. Targets, for example all known strains of HIV, are often closely related and finding unique probes becomes impossible. The use of non-unique oligonucleotides with more advanced decoding techniques from statistical group testing allows to detect known targets with great success. Of great relevance, however, is the problem of identifying the presence of previously unknown targets or of targets that evolve rapidly. RESULTS: We present the first approach to decode hybridization experiments using non-unique probes when targets are related by a phylogenetic tree. Using a Bayesian framework and a Markov chain Monte Carlo approach we are able to identify over 94% of known targets and assign up to 70% of unknown targets to their correct clade in hybridization simulations on biological and simulated data. AVAILABILITY: Software implementing the method described in this paper and datasets are available from http://algorithmics.molgen.mpg.de/probetrees.

Algorithms↗

PubMed1999

Do patients with acute medical conditions have the capacity to give informed consent for emergency medicine research?

OBJECTIVE: Because of stress and illness, conscious emergency medicine (EM) patients may be temporarily cognitively impaired and thus incapable of participating in the informed consent process for acute care research. This pilot study sought to assess the mental capacity of ED patients during their evaluation and treatment for acute myocardial infarction (AMI). METHODS: A prospective observational design at a university tertiary referral center. EM patients with AMI from November 1996 to February 1997 were enrolled. While usual care was delivered, patients were administered three subtests of the Wechsler Adult Intelligence Scale-Revised (WAIS-R) test. Subtest scaled scores range from 1 to 19, with abnormal being less than 5. Demographic, historical, and environmental parameters were recorded. Patients assessed how serious they perceived their conditions; and rated their degrees of pain, nausea, breathlessness, and anxiety on 10-cm visual analog scales (VASs). Testing was repeated prior to hospital discharge. RESULTS: Twenty-five patients were enrolled. Of these, two (8%) were suspected by their emergency physicians to have insufficient capacity to give informed consent. However, five (20%) scored less than 5 on all of the WAIS-R subtests (kappa = 0.5) and eight (32%) scored less than 5 on at least one of the subtests (kappa = 0.3). The initial median Digit Span, Comprehension, and Similarities subtest scores were 7, 5, and 6. By discharge, these improved to 8, 7, and 8, respectively. CONCLUSIONS: This pilot study suggests that some patients with AMI may have difficulty processing information necessary to give informed consent for acute care research. Routine clinical evaluation may not detect this cognitive defect.

Acute Disease↗

PubMed2004

An assessment of the efficacy and safety of eszopiclone in the treatment of transient insomnia in healthy adults.

BACKGROUND AND PURPOSE: This randomized, double-blind, placebo-controlled study assessed the efficacy and safety of eszopiclone, a non-benzodiazepine hypnotic agent, in healthy adults using the first-night effect model of transient insomnia. PATIENTS AND METHODS: A total of 436 healthy, normal sleeping participants were randomized to receive either eszopiclone 1, 2, 3, or 3.5mg, or placebo. Efficacy and next-morning effects were evaluated via polysomnography (PSG), Digit Symbol Substitution Test (DSST), and self-report. RESULTS: Patients treated with eszopiclone had significantly less PSG latency to persistent sleep (all doses except 1mg; P< or =0.0001), wake time after sleep onset (all doses; P< or =0.05) and number of awakenings (3 and 3.5mg doses; P<0.005), and greater sleep efficiency (all doses; P< or =0.02) compared with placebo. Self-reported efficacy results were similar to PSG. Self-reported morning sleepiness scores were significantly better for eszopiclone 3 and 3.5mg compared with placebo (P<0.05). Treatment was well tolerated by patients, and the most common treatment-related adverse event was unpleasant taste. CONCLUSIONS: In this model of transient insomnia, all doses of eszopiclone were more effective than placebo and were well tolerated by patients.

Adult↗

PubMed2003

Functionalizing inorganic solids: towards organic-inorganic nanostructured materials for intelligent and bioinspired systems.

The design, preparation, and properties of organic-inorganic hybrid compounds are described and discussed with respect to their potential uses as intelligent and bioinspired materials. Several synthesis strategies based on intercalation in 2D solids, the grafting of organic groups onto silica and silicates, and the self-assembly of organo-silica materials are presented, focusing on the soft procedures that are used to modify the functionality of the inorganic substrates. The combination of both organic and inorganic moieties at the nanometer level forms the basis for preparing multifunctional solids that are provided with specific functions in response to different types of stimuli. In some cases these resemble materials that are found in biological systems. Examples include organic-inorganic membranes that are based on intercalated macrocyclic compounds and bi-layer vesicles that consist of alkyl long-chains arranged either in the confined region of layered silicates or as self-organized organo-silica micelles. The role of certain hybrid materials such as membranes provides a different approach to the development of artificial liposomes and other mimetic systems that have an organic-inorganic composition and nanostructural organization. Their potential uses for DDS or DNA-dense phases are also discussed and novel alternatives to bioinspired systems development are proposed.

Biomedical Engineering↗

PubMed2000

New methods for detection of potential endocrine disruptors.

It has been hypothesized that recent adverse trends in humans are linked to an increased exposure to potential endocrine disrupting agents. These include widely used compounds that mimic the action of sex hormones, including bisphenol A, phthalates and parabens. Since the chemical structure is not sufficient to determine whether a chemical will act as an oestrogen, there is a need for assays that can determine whether a compound interferes with the endocrine systems. The Environmental Protection Agency has recently suggested a testing scheme, composed of an initial screening followed by a more comprehensive investigation of chemicals that are positive in the screening. The screening will use several short-term assays to screen many thousands of compounds for potential endocrine disrupting properties. However, none of these tests determines compound-induced effects on the expression of endogenous genes, which is the cause of the adverse effects. We propose to use a precise quantification of the expression levels of endogenous oestrogen-regulated genes to test whether a chemical has oestrogenic properties, and describe how an endogenous gene expression assay can be established and conducted. Furthermore, different applications of such an assay are discussed: in cell cultures; in experimental animals; or, optimally, directly in blood samples from exposed humans.

Animals↗

PubMed2004

The development of complex sentence interpretation in typically developing children compared with children with specific language impairments or early unilateral focal lesions.

This study compared sentence comprehension skills in typically developing children 5-17 years of age, children with language impairment (LI) and children with focal brain injuries (FL) acquired in the pre/perinatal period. Participants were asked to process sentences 'on-line', choosing the agent in sentences that varied in syntactic complexity (actives, passives, subject clefts and object clefts), and in the presence or absence of a subject-verb agreement contrast. Results revealed that accuracy and processing speeds vary with syntactic complexity in all groups, reflecting the frequency and regularity of sentence types. Developmental changes continued throughout childhood, as children became faster and more accurate at processing more complex sentence structures. Children with LI and children with FL were quite profoundly delayed, displaying profiles similar to, or more impaired than those of younger children, but there was no evidence in the FL group for a disadvantage in left- vs. right-hemisphere-damaged children. Children with LI showed one unique pattern: higher than normal costs (reflected in reaction times) in using converging information from subject-verb agreement, in line with studies suggesting special vulnerabilities in grammatical morphology in this group. Results are discussed in terms of the Competition Model, a theory of language processing designed to account for the statistical changes in performance that are observed during development, and the probabilistic deficits in children with language impairments.

Adolescent↗

PubMed2005

Cognitive effects of modafinil in student volunteers may depend on IQ.

The results of two previous studies on the effects of modafinil, a selective wakefulness-promoting agent, in healthy university students were combined in a retrospective analysis. This allowed determination of whether the effects of modafinil were dependent on IQ and whether the larger sample size (n=89) would reveal more cognitive benefits. A battery of cognitive tests was completed 2-3 h after dosing. In the whole sample, modafinil (200 mg) significantly reduced the number of missed targets in a test of sustained attention (RVIP). However, interestingly, several interactions between modafinil and IQ emerged. Modafinil (100 and 200 mg) significantly improved target sensitivity in the RVIP test, but only in the group of 'lower' IQ (mean+/-sem=106+/-0.6), not in the 'higher' IQ group (mean+/-sem=115.5+/-0.5). Furthermore, there were significant modafinil x IQ interactions in two further tests. Modafinil significantly reduced speed of responding in a colour naming of dots, and in clock drawing, but only in the 'lower' IQ group. Thus, the cognitive benefits of modafinil seem particularly marked in tests of vigilance and speed, in which sleepiness would be an important factor. Furthermore, the results indicate that high IQ may limit detection of modafinil's positive effects.

Adult↗

PubMed2004

Design of a novel hydrogel-based intelligent system for controlled drug release.

The present work focused on the design of an assembled drug delivery system (DDS) to provide multifunctions, such as drug protection, self-regulated oscillatory release, and targeted uni-directional delivery by a bilayered self-folding gate and simple surface mucoadhesion. In this device, a pH-sensitive hydrogel together with a poly(hydroxyethyl methacrylate) (HEMA) barrier was used as a gate to control drug release. In addition, poly(HEMA) coated with poly(ethylene oxide)/poly(propylene oxide)/poly(ethylene oxide) (PEO-PPO-PEO) surfactant was utilized to enhance mucoadhesion on the device surface. The release profiles of two model drugs, acid orange 8 (AO8) and bovine serum albumin (BSA) were studied in this assembled system, which compared with the conventional drug-entrapped carriers and enteric-coating systems. Furthermore, targeted uni-directional release was demonstrated in a side-by-side diffusion cell. In conclusion, for such an assembled device, the poly(HEMA) layer not only affects the folding direction but also serves as a barrier to protect the model drugs. The release time can be controlled by the thickness of the bilayered gate and the drug reservoir. Due to the reversible swelling behavior of poly(methyacrylic acid-g-ethylene glycol) (p(MAA-g-EG)) gels, the bilayered gate can sense the environmental pH change and achieve an oscillatory release pattern. Moreover, the local targeting and uni-directional release have been successfully demonstrated in vitro.

Coloring Agents↗

PubMedDate not supplied

DIABNET: a qualitative model-based advisory system for therapy planning in gestational diabetes.

An intelligent decision support system for the analysis of home monitoring data and therapy planning in gestational diabetes is presented. The paper describes the integration of qualitative and quantitative reasoning modules within the DIABNET advisory system. The system kernel is a qualitative model of the physiological processes involved in the glucose metabolism of this type of diabetic patient. A causal probabilistic network (CPN) has been used to represent the qualitative model in order to manage uncertain and missing monitoring data. The DIABNET inputs are the patient's available ambulatory monitoring data, and the output is a dietary and insulin therapy adjustment that includes initiation of insulin therapy, quantitative insulin dose changes and qualitative diet and schedule modifications. Over periods of up to seven days, monitoring data are analysed by the CPN to detect any diet or insulin therapy items which may require modification. The qualitative insulin needs are translated into a quantitative proposal in line with the characteristics of the patient and the modification strategies usually used by doctors. The first evaluation of the system has been accomplished, the encouraging results of which are also presented.

Blood Glucose Self-Monitoring↗

PubMed1997

Self-learning fuzzy control of atracurium-induced neuromuscular block during surgery.

Self-learning fuzzy logic control has the important property of accommodating uncertain, non-linear and time-varying process characteristics. This intelligent control scheme starts with no fuzzy control rules and learns how to control each process presented to it in real time, without the need for detailed process modelling. A suitable medical application to investigate this control strategy is atracurium-induced neuromuscular block (NMB) of patients in the operating theatre. Here, the patient response exhibits high non-linearity, and individual patient dose requirements can vary five-fold during an operating procedure. A portable control system was developed to assess the clinical performance of a simplified self-learning fuzzy controller in this application. A Paragraph (Vital Signs) NMB device monitored T1, the height of the first twitch in a train-of-four nerve stimulation mode. Using a T1 setpoint = 10% of baseline in ten patients undergoing general surgery, a mean T1 error of 0.45% (SD = 0.44%) is found while a 0.13-0.70 mg k-1 h-1 range in the mean atracurium infusion rate is accommodated. The result compares favourably with more complex and computationally-intensive model-based control strategies for the infusion of atracurium.

Atracurium↗

PubMed2005

Methodological issues in research on developmental exposure to neurotoxic agents.

In the literature on the effects of early exposure to neurotoxic agents on infant and child development, considerable attention has been devoted to two important issues--ascertainment of exposure and spurious correlation. In this paper, we review these research challenges and focus on three additional issues that, in our view, warrant more attention than they have received to date--multiple comparisons, effect modifiers, and clinical significance. Alternatives to the Bonferroni approach to multiple comparisons, which entails an unacceptably high risk of Type II error, include the designation of a limited number of primary endpoints for hypothesis testing, an evaluation of the consistency of effects across multiple related endpoints, and replication. Effect modifiers are important for understanding the marked individual differences in vulnerability that characterize most neurodevelopmental exposures. In evaluating effect modification, separate analyses comparing high and low risk groups provide an alternative to statistical interaction terms, which are underpowered in most longitudinal field studies. Because the small effect sizes that emerge in most large sample studies understate the impact of an exposure on the most vulnerable individuals, it is important to evaluate the functional significance of the impairment on such individuals directly in order to assess its true public health impact.

Child↗

PubMed2000

Febrile seizures: treatment and prognosis.

Recent epidemiologic data indicate that the vast majority of children with febrile seizures have a normal longterm outcome. A precise knowledge of the short- and long-term outcome with or without treatment, and short- and long-term side effects is an important prerequisite for assessing the various treatment strategies. We focus on the impact of short-term or prophylactic treatment on the short- and long-term outcome of various types of febrile seizures. There is universal agreement that daily prophylaxis with antiepileptic agents should never be used routinely in simple febrile seizures, but only in highly selected cases, if at all. Intermittent diazepam (DZP) prophylaxis at times of fever may or may not reduce the recurrence rate, but it does not appear to improve the long-term outcome as compared with short-term seizure control. The treatment may be used to reduce the recurrence rate for a small arbitrarily defined group with multiple simple febrile seizures, complex febrile seizures, especially focal, prolonged or both, febrile status, and when parental anxiety is severe. However, there is no evidence that treatment of simple febrile seizures can prevent the rare cases of later epilepsy, and many children with complex febrile seizures have a benign long-term outcome, even without treatment. Many prefer a "wait and see" policy. An attractive alternative is to treat new febrile seizures with rectal DZP in solution at seizure onset, given by the parents at home to prevent febrile status. Newer, less well documented short-term strategies include nasal, oral, or rectal administration of other benzodiazepines. Short-term seizure control of febrile status and careful parental counseling are the two most important targets of treatment.

Analgesics, Non-Narcotic↗

PubMed2003

Prolactin levels during long-term risperidone treatment in children and adolescents.

BACKGROUND: This analysis was designed to investigate prolactin levels in children and adolescents on long-term risperidone treatment and explore any relationship with side effects hypothetically attributable to prolactin (SHAP). METHOD: Data from 5 clinical trials (total N = 700) were pooled for this post hoc analysis. Children and adolescents aged 5 to 15 years with subaverage intelligence quotients and conduct or other disruptive behavior disorders received risperidone treatment (0.02-0.06 mg/kg/day) for up to 55 weeks. Outcome measures analyzed included serum prolactin levels, reported adverse events, and the conduct problem subscore of the Nisonger Child Behavior Rating Form. RESULTS: Mean prolactin levels rose from 7.8 ng/mL at baseline to a peak of 29.4 ng/mL at weeks 4 to 7 of active treatment, then progressively decreased to 16.1 ng/mL at weeks 40 to 48 (N = 358) and 13.0 ng/mL at weeks 52 to 55 (N = 42). There was no relationship between pro-lactin levels and age. Females returned to a mean value within the normal range (</= 30 ng/mL) by weeks 8 to 12, and males were close to normal values (</= 18 ng/mL) by weeks 16 to 24. At least 1 SHAP was reported by 13 (2.2%) of 592 children. There was no direct correlation between prolactin elevation and SHAP. CONCLUSION: With long-term risperidone treatment in children and adolescents, serum prolactin levels tended to rise and peak within the first 1 to 2 months and then steadily decline to values within or very close to the normal range by 3 to 5 months.

Adolescent↗

PubMed1992

Patient compliance with oral chemotherapy as assessed by a novel electronic technique.

PURPOSE: Previous reports have suggested low rates of compliance with the oral component of cancer chemotherapy, which, if confirmed, would have serious implications on treatment. Because of the uncertainties in the methodology used in previous studies, we have assessed compliance with a novel technique. PATIENTS AND METHODS: An "intelligent" tablet bottle was used, which, unknown to the patient, electronically records the times of opening over a period of weeks. The records were scored for overall compliance (total number of bottle openings as a percentage of the prescribed number) and for daily and hourly irregularity indices. Twenty-one patients undergoing treatment for Hodgkin's or non-Hodgkin's lymphoma were monitored for a total of 65 treatment periods, each of up to 2 weeks (852 days in total). Eight measures of side effects and quality of life were self-assessed daily by the patients using a diary card. RESULTS: The overall compliance was 100.6% +/- 20.6% (mean +/- SD). Overall compliance was lower (mean reduction, 10%) in treatment periods with drugs prescribed to be taken three times a day. It was not possible to demonstrate convincingly any relationship between compliance and any of the following: drug type, monitoring period sequence, the diary card scores of side effects and quality of life, number of relapses, and time since initial diagnosis. CONCLUSION: These results are reassuring, but further work is in progress to measure compliance in other treatment regimens in which the side effects are more severe and the prognosis is worse.

Administration, Oral↗

PubMed1982

Cancer of larynx in west of Scotland. A review of results and a consideration of new therapeutic approaches.

A recent epidemiological study carried out by the Cancer Intelligence Unit in Glasgow has shown: 1) there has been an increase in consumption of tobacco products and alcohol in Scotland over the past 25 years; and 2) the mortality rate from cancer of the larynx has been unchanged over that time (Fig. 1). Ayrshire, a county in the west of Scotland, has a population of 360,000 which is remarkably similar in age structure, sex and urban/rural mix to Scotland as a whole. The incidence of carcinoma of the larynx in this region has been unchanged over the 20-year period 1959-1978. The results of treatment for the period 1958-1968 were reported recently by Quayum. In this report the results of treatment of carcinoma of the larynx by radiotherapy in Ayrshire and district over the decade 1968-1978 are presented and compared with those of the previous decade. The overall survival is unchanged over the two decades 1958-68 and 1968-78. This confirms the findings of the Cancer Registry. The survival of certain stages has improved, though this may be due to changes in criteria for staging introduced in 1974. All cases in this report were staged retrospectively. Recent innovations in treatment which may improve overall survival are considered.

Adult↗

PubMed2026

Recent advancements in exosomal content analysis: the future of liquid biopsy.

Exosomes are widely acknowledged as an essential agent that carries biomarkers for specific diseases, representing the molecular status of their parent cells and providing extremely useful diagnostic insights. They can be isolated from different body fluids and contain a range of cargo molecules, including proteins, lipids, metabolites, and nucleic acids. Recent advancements in technology have greatly accelerated exosome research. Proteomics provides protein signatures linked to many pathological conditions, enabling quick and clinically scalable diagnostic tools, whereas high-throughput RNA-sequencing can be used to perform detailed transcriptome profiling. Exosomal biomarkers are showing promising clinical results in early detection of neurological diseases, infectious and cardiovascular disorders, oncology, and other medical conditions, hence accelerating therapeutic monitoring. Despite these advances, several challenges continue to hinder clinical translation including the lack of standardized isolation protocol, variability in exosome yield and purity, biological heterogeneity, and limited large-scale clinical validation. Addressing these limitations will be critical for the successful integration of exosome-based liquid biopsy into routine clinical practice. Overall, exosomes having significant potential as diagnostic tool, represent a transformative horizon in biomedical liquid biopsy research to redefine the landscape of less-invasive diagnostics and tailored clinical applications.

Humans↗

PubMed2002

Double-blind, placebo-controlled study of risperidone for the treatment of disruptive behaviors in children with subaverage intelligence.

OBJECTIVE: The short-term efficacy and safety of risperidone in the treatment of disruptive behaviors was examined in a well-characterized cohort of children with subaverage intelligence. METHOD: In this 6-week, multicenter, double-blind, parallel-group study of 118 children (aged 5-12 years) with severely disruptive behaviors and subaverage intelligence (IQ between 36 and 84, inclusive), the subjects received 0.02-0.06 mg/kg per day of risperidone oral solution or placebo. The a priori primary efficacy measure was the change in score from baseline to endpoint on the conduct problem subscale of the Nisonger Child Behavior Rating Form. RESULTS: The risperidone group showed significantly greater improvement than did the placebo group on the conduct problem subscale of the Nisonger Child Behavior Rating Form from week 1 through endpoint (change in score of -15.2 and -6.2, respectively). Risperidone was also associated with significantly greater improvement than placebo on all other Nisonger Child Behavior Rating Form subscales at endpoint, as well as on the Aberrant Behavior Checklist subscales for irritability, lethargy/social withdrawal, and hyperactivity; the Behavior Problems Inventory aggressive/destructive behavior subscale; a visual analogue scale of the most troublesome symptom; and the Clinical Global Impression change score. The most common adverse effects reported during risperidone treatment were headache and somnolence. The extrapyramidal symptom profile of risperidone was comparable to that of placebo. Mean weight increases of 2.2 kg. and 0.9 kg occurred in the risperidone and placebo groups, respectively. CONCLUSIONS: Risperidone was effective and well tolerated for the treatment of severely disruptive behaviors in children with subaverage IQ.

Aggression↗