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At least 1,423 records · Page 79Linked to original sources
PubMed2005

Unilateral intracarotid amobarbital procedure for language lateralization.

PURPOSE: The determination of language dominance as part of the presurgical workup of patients with pharmacoresistant epilepsies has experienced fundamental changes. With the introduction of noninvasive functional magnetic resonance imaging (fMRI), the number of patients receiving intracarotid amobarbital procedures (IAPs) for assessment of language dominance has decreased considerably. However, recent studies show that because of methodologic limitations of fMRI, IAP remains an important tool for language lateralization. The current study examines whether unilateral instead of bilateral IAP is an adequate way to apply IAP with reduced invasiveness. METHODS: We retrospectively examine the predictive value of unilateral IAP for the results of bilateral IAP based on a sample of 75 patients with various types of language dominance. Target parameters are the prediction of the language-dominant hemisphere and the identification of patients with atypical language dominance. For language assessment based on unilateral IAP, we introduce the measure hemispheric language capacity (HLC). RESULTS: Unilateral IAP performed on the side of intended surgery quantifies language capacity contralateral to the intended surgery. It detects atypical (bilateral or right) language dominance in the majority of patients. Experience with a separate series of 107 patients requiring presurgical language lateralization shows that in >80%, bilateral IAPs are redundant. CONCLUSIONS: Unilateral IAP is principally sufficient for language lateralization in the presurgical evaluation of patients with pharmacoresistant epilepsies. Necessity of bilateral IAP is restricted to few indications (e.g., callosotomy). In times of noninvasive language lateralization, we propose unilateral IAP as the method of choice for the verification of doubtful (bilateral) fMRI activation patterns.

Adolescent↗
PubMed2002

Four cell types with distinctive membrane properties and morphologies in lamina I of the spinal dorsal horn of the adult rat.

Lamina I of the spinal dorsal horn plays an important role in the processing and relay of nociceptive information. Signal processing depends, in part, on neuronal membrane properties. Intrinsic membrane properties of lamina I neurons were therefore investigated using whole cell patch clamp recordings in a slice preparation of adult rat spinal cord. Based on responses to somatic current injection, four cell types were identified: tonic, which fire comparatively slowly but continuously throughout stimulation; phasic, which fire a high frequency burst of variable duration; delayed onset, which fire irregularly and with a marked delay to the first spike; and single spike, which typically fire only one action potential even when strongly depolarised. Classification by spiking pattern was further refined by identification of characteristic stimulus-response curves and quantification of several response parameters. Objectivity of the classification was confirmed by cluster analysis. Responses to stimulus trains and synaptic input as well as the kinetics of spontaneous synaptic events revealed differences in the signal processing characteristics of the cell types: tonic and delayed onset cells appeared to act predominantly as integrators whereas phasic and single spike cells acted as coincidence detectors. Intracellular labelling revealed a significant correlation between morphological and physiological cell types: tonic cells were typically fusiform, phasic cells were pyramidal, and delayed onset and single spike cells were multipolar. Thus, there are multiple physiological cells types in lamina I with specific morphological correlates and distinctive signal processing characteristics that confer significant differences in the transduction of input into spike trains.

Animals↗
PubMed2003

Evaluation of anthropometric, physiological, and skill-related tests for talent identification in female field hockey.

The purpose of the present study was to develop an effective testing battery for female field hockey by using anthropometric, physiological, and skill-related tests to distinguish between regional representative (Rep, n = 35) and local club level (Club, n = 39) female field hockey players. Rep players were significantly leaner and recorded faster times for the 10-m and 40-m sprints as well as the Illinois Agility Run (with and without dribbling a hockey ball). Rep players also had greater aerobic and lower body muscular power and were more accurate in the shooting accuracy test, p < 0.05. No significant differences between groups were evident for height, body mass, speed decrement in 6 x 40-m repeated sprints, handgrip strength, or pushing speed. These results indicate that %BF, sprinting speed, agility, dribbling control, aerobic and muscular power, and shooting accuracy can distinguish between female field hockey players of varying standards. Therefore talent identification programs for female field hockey should include assessments of these physical parameters.

Adult↗
PubMed2005

Long-term enteral nutrition support and the risk of dehydration.

Dehydration is a serious risk for the long-term tube-fed patient who is not allowed oral intake, has an altered mental status, is unable to communicate, is elderly or fluid-restricted, or has thirst impairment. The intent of this review is to provide a case-based discussion regarding the evaluation, treatment, and prevention of dehydration in these types of patients. Identification of risk factors, along with evaluation of subjective, objective, and laboratory parameters, provides the basis for clinical evaluation. "Hidden" sources of fluid intake such as the water content of solid foods and water generated from nutrient oxidation and "hidden" sources of fluid output such as evaporative losses should be considered in waterbalance calculations. The method for treatment and prevention of dehydration depends on the presence or absence of hypovolemia, type of body fluid losses, and whether the patient demonstrates hypernatremia, normonatremia, or hyponatremia.

Dehydration↗
PubMed2003

Laboratory results in the elderly: the Sydney Older Persons Study.

BACKGROUND: The use of laboratory intervals based on younger and healthier populations is of questionable validity in older populations. The aim of this study was to examine haematological and biochemical profiles in a sample of community-dwelling older people and to study the impact of age, disease, disability and medications. METHODS: Basic haematological and biochemical values were obtained for 338 survivors of a random sample of community-living people aged 75 years or over at time of recruitment. These values were compared to the laboratory reference intervals and the effects of age, disease, medication and disability examined. RESULTS: The distribution of the 35 parameters measured differed from those described by the laboratory reference intervals in all but four of the variables. The values showed few significant age associations but did show associations with disease, disability and drug use. CONCLUSIONS: Abnormalities identified in haematological and biochemical testing are not due to age but to age-related illnesses. This is contrary to previous studies reporting a change in haematological and biochemical parameters purely on the basis of age. In the presence of abnormalities, identification and clarification of disease states should be made.

Aged↗
PubMedDate not supplied

A critical evaluation of the therapeutic range of indinavir.

OBJECTIVE: To provide a summary of the patient population, study characteristics, and important findings of the key studies in the literature evaluating concentration-effect relationships and the therapeutic range for indinavir. DATA SOURCES: Literature search strategy involved using MEDLINE (1966-July 2001) and AIDSLINE (MEDSCAPE) databases (up to July 2001). Reference lists from primary literature and review articles were also examined, and conference abstracts were obtained. STUDY SELECTION: English-language articles were considered suitable for review if the clinical trials in HIV patients reported on concentration-effect relationships and/or pharmacokinetic breakpoints or threshold concentrations. A search of the literature identified 20 peer-reviewed references from 18 separate studies including journal articles and conference abstracts. DATA EXTRACTION: The targeted pharmacokinetic parameters and breakpoint values, the rationale for their selection or method of identification, and other study details and limitations were summarized. DISCUSSION: This article highlights the heterogeneity of studies evaluating the therapeutic range of indinavir and provides a summary of important findings of the key studies in the literature evaluating concentration-effect relationships and therapeutic range. Tables are provided to enable clinicians to make use of currently available information on the therapeutic range of indinavir. CONCLUSIONS: There is insufficient evidence to recommend a general therapeutic range for indinavir. Future investigations should incorporate both pharmacokinetics and pharmacodynamics in order to define a broadly applicable therapeutic range.

Adult↗
PubMed1997

Micro-telerobotic surgical system for microsurgery.

Modern surgical methods which utilize microscopes have allowed medical professionals to visualize the surgical field on the order of microns. This new found visual capacity has created a performance gap between a surgeon's visual skills and manipulative skills that surgical robotics have the capability to remedy. Robotics can be used as an aid to the surgeon to help correct natural human dexterity problems such as tremor and resolution of motion. Devices that would benefit surgical dexterity at the micron scale are in development at Sandia National Laboratories. A six degree-of-freedom (DOF) force reflecting telerobotic manipulator has been designed and developed for use in microsurgical applications. The system utilizes a unique mechanical platform, actuation schemes, and controller that provides high positional precision while maintaining high frequency response for implementation of force feedback. Thus, the same device is used to form a master-slave telerobotic arrangement to assist the surgeon. This makes the system very intuitive to the surgeon and easier to implement for the engineer. The system utilizes high performance Digital Signal Processors (DSP) for control of both the master and slave platforms. Six dimensional force information is obtained from transducers located at the end effectors of both the master and slave. Two distinctly different types of motors are currently being evaluated, as well as several types of control algorithms. Position scaling, force scaling, and tremor filtering are being implemented in the DSP control software. Control parameters are based upon system frequency response testing. Results from our system identification and performance testing will be discussed.

Computers↗
PubMed1993

A three-dimensional approach to multistream migration modelling: local-level flows in Hereford and Worcester.

Using data for the English county of Hereford and Worcester, the author presents a method for the analysis of migration at the local level "which does not disaggregate migrant flows by distance criteria alone, but incorporates measures relating to the nature of the origins and of the destinations." The author suggests that "in comparison with a standard single-stream regression model this method improves the fit substantially, and the variability in the resulting parameter estimates for each of the eight streams supports the need for identification of distinct migrant streams. In particular, flows over short distances between wards with high population densities are estimated more effectively."

Demography↗
PubMed2003

[Clinical study on hematopoietic reconstitution in patients with leukemia by haploidentical bone marrow transplantation].

To investigate the properties of haploidentical donor-derived bone marrow engraftment and hematopoietic reconstitution in patients received bone marrow transplantation, 15 patients with leukemia received bone marrow grafts without T cell depletion from their family donors of those with 2-3 mismatched loci of HLA antigens. The donors were given G-CSF 250 micro g/day for 7 days prior to marrow harvest. All patients were treated with conditioning regimens consisting of high-dose of Ara-C, cyclophosphamide, and total body irradiation. A four-agent based GVHD prophylaxis was used as cyclosporine A, MTX, ATG and mycophenolate mofetile (MMF). Donor engraftment was evaluated as identification of HLA locus, chromosome karyotype, DNA fingerprinting, blood type and other parameters such as occurrence of GVHD, recovery of peripheral blood cell counts as well as normal myelogram. The results showed that successful and stable engraftment was established in all patients. The median time of granulocyte counts > 0.5 x 10(9)/L and platelet > 20 x 10(9)/L was 18 (13-23) and 22 (16-32) days, respectively. One of the patients relapsed despite the bone marrow chimerism appearing after transplantation. The grade I acute GVHD occurred in 8 and grade II-IV in 5 of the 15 patients. Of the patients, 7 received marrow grafts from donors of opposite sex were identified for donor engraftment by chromosome analysis, 4 by blood typing, 7 with HLA locus analysis and 1 with DNA fingerprinting. In conclusion, HLA haploidentical bone marrow transplantation is feasible with a series of management including mobilization with G-CSF in donors, intensive conditioning and proper immunosuppressants, which enable the allo-transplants to stride across the immunological barrier.

Adolescent↗
PubMed2004

[Bovine leukemia virus as a model for studying human leukemias].

Bovine leukemia virus (BLV) is a retrovirus responsible for lymphoproliferative disorders in ruminants. The comprehensive study of this model system permitted the identification of genetic determinants required for leukemogenesis, the quantification of the dynamic parameters responsible for cell accumulation and the elaboration of novel therapeutic approaches in human.

Animals↗
PubMed1990

[Pharmaceutical characterization and spectroscopy of AWD 26-06].

To fix parameters for the pharmaceutical characterization of AWD 26-06 test methods converting identification, purity, content and stability as well as their results are submitted. Spectroscopic investigations are intended to give information on the constitution of the molecule.

Anti-Ulcer Agents↗
PubMed1981

[Results from the Central Laboratory for Streptococci Research in Kiel from 1965 to 1980 - group D-streptococci (enterococci) (author's transl)].

In accordance with previous papers published within a series of publications which describe the results obtained from the Central Laboratory for Streptococcal Research in Kiel (1. Survey, 2. Mastitis-Streptococci) the group of Enterococci is discussed herewith. On the basis of more than 6000 strains which are stored in our databank including all biological characteristics, the distribution of the cultural, biochemical and serological parameters is listed in percentages, and the usefulness and reliability for the identification of the enterococcal group and also the differentiation of particular species is discussed. The results are tabulated for every single species and additionally, for serologic-positive and negative strains. For example, it can be shown that a third of all Str. faecium strains are motile, that lack of growth at 45 degrees C varies between 1.1% and 31.3% and that lack of serological reaction with group D-serum between 0.9% and 70%. In a comprehensive table and flow diagram these figures result in a proposal for a simple but sufficient identification procedure on different stages (enterococci, faecalis- or faecium-group, single species) depending on the individual requirements. With regard to the incidence of enterococci in man and animals, which was presented in the first paper, the organ sources of the different species are compared now. Apart from some interesting findings it can be stated that a typical predominance of the faecalis and faecium-group resp. in man or animals cannot be confirmed. But there seems to be a relation between the species and the organ source. For example, in humans the faecium-group predominates in the respiratory tract, but in the urogenital tract the presence of Str. faecalis is seven times higher than the faecium-group. The above results may also be of interest for ecological reasons and may be important for the pathogenesis and epidemiology of this streptococcal group.

Animals↗
PubMed1997

Morphological and biochemical status of the mammary gland as influenced by conjugated linoleic acid: implication for a reduction in mammary cancer risk.

Previous research showed that treatment with conjugated linoleic acid (CLA) during the period of active mammary gland morphogenesis was sufficient to confer a lasting protection against subsequent mammary tumorigenesis induced by methylnitrosourea. The present study was designed to characterize certain morphological and biochemical changes of the mammary gland that might potentially render it less susceptible to cancer induction. Female Sprague Dawley rats were fed a 1% CLA diet from weaning until about 50 days of age. The mammary gland parameters under investigation included (a) the deposition of neutral lipid, (b) the identification and quantification of CLA and its metabolites, (c) the density of the epithelium, and (d) the proliferative activity of various structural components. Our results showed that CLA treatment did not affect total fat deposition in the mammary tissue nor the extent of epithelial invasion into the surrounding fat pad but was able to cause a 20% reduction in the density of the ductal-lobular tree as determined by digitized image analysis of the whole mounts. This was accompanied by a suppression of bromodeoxyuridine labeling in the terminal end buds and lobuloalveolar buds. The recovery of desaturation and elongation products of CLA in the mammary gland confirmed our prior suggestion that the metabolism of CLA might be critical to risk modulation. The significance of the above findings was investigated in a mammary carcinogenesis bioassay with the use of the dimethylbenz[a]anthracene model. When CLA was started at weaning and continued for 6 months until the end of the experiment, this schedule of supplementation produced essentially the same magnitude of mammary tumor inhibition in the dimethylbenz[a]anthracene model as that produced by 1 month of CLA feeding from weaning. The observation is consistent with the hypothesis that exposure to CLA during the time of mammary gland maturation may modify the developmental potential of a subset of target cells that are normally susceptible to carcinogen-induced transformation.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed2005

Auto-tuning of PID controller parameters with supervised receding horizon optimization.

In this paper, a novel two-layer online auto-tuning algorithm is presented for a nonlinear time-varying system. The lower layer consists of a conventional proportional-integral-derivative (PID) controller and a plant process, while the upper layer is composed of identification and tuning modules. The purpose of the upper layer is to find a set of optimal PID parameters for the lower layer via an online receding horizon optimization approach, which result in a time-varying PID controller. Through mathematical analysis, the proposed system performance is equivalent to that of a standard generalized predictive control. Simulation and experiment demonstrate that the new method has a better control system performance compared with conventional PID controllers.

Journal Article↗
PubMed2006

Separation and identification of isomeric acidic degradation products of organophosphorus chemical warfare agents by capillary electrophoresis-ion trap mass spectrometry.

Capillary electrophoresis (CE) coupled to ion trap mass spectrometry (MS) was evaluated for the separation and identification of chemical warfare agent degradation products (alkylphosphonic acids and alkyl alkylphosphonic acids). Different analytical parameters were optimized in negative ionization mode such as electrolyte composition (15 mM CH(3)COONH(4), pH 8.8), sheath liquid composition (MeOH/H(2)O/NH(3), 75:25:2, v/v/v), nebulization and ion trapping conditions. A standard mixture of five alkylphosphonic (di)acids and five alkyl alkylphosphonic (mono)acids containing isomeric compounds was used in order to evaluate CE selectivity and MS identification capability. The obtained electropherograms revealed that CE selectivity was very limited in the case of alkyl alkylphosphonic acid positional isomers, whereas isomeric isopropylphosphonic and propylphosphonic acids were baseline-separated. CE-MS-MS experiments provided an unambiguous identification of each isomeric co-migrating alkyl alkylphosphonic acids thanks to the presence of specific fragment ions. On the other hand, CE separation was mandatory for the identification of isomeric alkylphosphonic acids, which led to the same fragment ion and could not be differentiated by MS-MS. The developed method was applied to the analysis of soil extracts spiked with the analytes (before or after extraction treatment) and appeared to be very promising since resolution and sensitivity were similar to those observed in deionized water. Especially, analytes were detected and identified in soil extract spiked at 5 microg mL(-1) with each compound before extraction treatment.

Chemical Warfare Agents↗
PubMed2006

Use of various common isolation media to evaluate the new VITEK 2 colorimetric GN Card for identification of Burkholderia pseudomallei.

The use of automated systems in the modern microbiology laboratory is becoming commonplace as the pressure of cost containment impacts on staff resources. With increased international travel and threats of bioterrorism, recognition and accurate identification of organisms such as Burkholderia pseudomallei is important. In areas where this organism is endemic, identification is not usually problematic. This study evaluates the performance of the new VITEK 2 colorimetric GN card for the identification of this organism. A total of 103 previously identified clinical isolates were tested with the new card with isolates taken from MacConkey agar, Columbia horse blood agar, Columbia sheep blood agar, and Trypticase soy agar in order to determine identification performance and to see if there was any variability in results due to the agar. Columbia horse blood agar produced the highest rates of identification (81%), followed by Trypticase soy agar (78%), Columbia sheep blood agar (75%), and MacConkey agar (63%). There was considerable variability in some of the reactions obtained. Seven isolates failed to identify from any of the agars used. This study highlights issues with the identification of this organism with the new VITEK 2 GN card. Enhancements of the algorithm parameters for the GN card are warranted and are in progress. Laboratory personnel need to be aware of the current limitations with this GN card and the software (version 4.02 or older for the VITEK 2 60/XL and version 1.02 or older for VITEK 2 Compact) and rely on clinical history, a high index of suspicion, and basic microbiology tests to confirm the identification of this organism.

Agar↗
PubMed2000

Practice parameter: screening and diagnosis of autism: report of the Quality Standards Subcommittee of the American Academy of Neurology and the Child Neurology Society [RETIRED].

Autism is a common disorder of childhood, affecting 1 in 500 children. Yet, it often remains unrecognized and undiagnosed until or after late preschool age because appropriate tools for routine developmental screening and screening specifically for autism have not been available. Early identification of children with autism and intensive, early intervention during the toddler and preschool years improves outcome for most young children with autism. This practice parameter reviews the available empirical evidence and gives specific recommendations for the identification of children with autism. This approach requires a dual process: 1) routine developmental surveillance and screening specifically for autism to be performed on all children to first identify those at risk for any type of atypical development, and to identify those specifically at risk for autism; and 2) to diagnose and evaluate autism, to differentiate autism from other developmental disorders.

Asperger Syndrome↗
PubMed1998

Hepatocyte proliferation rate is a powerful parameter for predicting hepatocellular carcinoma development in liver cirrhosis.

AIMS: A sound predictive test is lacking for the identification of cirrhotic patients at high risk of developing hepatocellular carcinoma. The present study evaluates the measurement of hepatocyte expression of silver stained nucleolar organiser region (AgNOR) proteins as a risk factor for the development of hepatocellular carcinoma in cirrhosis. METHODS: Liver biopsies from 176 cirrhotic patients included in a follow up surveillance programme for hepatocellular carcinoma development were evaluated prospectively for hepatocyte AgNOR protein quantity. The follow up programme consisted of clinical and biochemical assessment every three months, and ultrasound scanning and serum alpha-fetoprotein (alpha FP) assessment every six months. Histological sections from the needle biopsies performed at enrollment were stained selectively for AgNOR proteins and the percentage of hepatocytes with an AgNOR protein area > or = 7 micron 2, indicative of a proliferative state (AgNOR proliferation index (AgNOR-PI)), was measured. RESULTS: During the mean (SD) follow up time of 65.5 (36.29) months (range, 12-143; median, 67), hepatocellular carcinoma was diagnosed in 48 of 176 patients (27.3%). The AgNOR-PI of the whole series ranged from 0% to 5% (median, 0.9%), and was significantly higher in patients with liver cell dysplasia and hepatitis B surface antigen (HBsAg) positivity (p < 0.0001 and p = 0.0002, respectively). The 176 patients were divided into two groups according to their AgNOR-PI scores; a cut off value of 2.5% defined by the receiver operating characteristic curve and the Youden index was used. Forty two patients were included in the high AgNOR-PI (< 2.5%) group, and 134 patients the low AgNOR-PI (< 2.5%) group. In the high AgNOR-PI group, 25 of 42 patients developed hepatocellular carcinoma, in contrast to only 23 of 134 patients (17.2%) in the group with a low AgNOR-PI (p < 0.0001). Hepatocellular carcinoma development was also significantly more frequent in patients with liver cell dysplasia and HBsAg positivity. Multivariate analysis using AgNOR-PI, liver cell dysplasia, HBsAg positivity, and hepatitis C virus (HCV) infection as covariates demonstrated that the AgNOR-PI parameter was the only significant predictor of hepatocellular carcinoma development. CONCLUSIONS: These results demonstrate that a high hepatocyte proliferation rate is a major risk factor for hepatocellular carcinoma development in the cirrhotic liver. Therefore, the evaluation of the hepatocyte proliferation rate is very important to identify patients requiring a more strict follow up programme for early diagnosis of hepatocellular carcinoma.

Adult↗