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PubMed2005

Adaptation and performance of an immuno-PCR assay for the quantification of Aviscumine in patient plasma samples.

An immuno-polymerase chain reaction (IPCR) assay is used to evaluate the kinetic behaviour of the novel anti-cancer drug Aviscumine in plasma samples taken from 41 patients during a 3-year clinical trial. The ultrasensitive IPCR assay employed the amplification of a detection-antibody linked marker-DNA and an internal competitor DNA for standardization, thus enabling the detection of the antigen in concentrations far below the detection limit of conventional enzyme-linked immuno-sorbent assay (ELISA). The quantification of Aviscumine was carried out using external calibration curves obtained from individual patient plasma samples, collected previous to the administration of Aviscumine, which were spiked with known amounts of the reference substance Aviscumine. Additional controls were measured containing standardized human serum spiked with Aviscumine to assure the continuous general reproducibility of the assay as well as to estimate differences between individual patients. Average recovery was found to be 95+/-19% and the average deviation in precision of the assay was determined to be 9+/-5%. Data for the quantification of Aviscumine were obtained from all patient samples investigated with the exception of a single patient. The collected data provided the basis for the valid routine quantification of patient samples for the calculation of the pharmacokinetic behaviour of Aviscumine in patient plasma.

Algorithms↗
PubMed1996

An extended sampling of the configurational space of HPr from E. coli.

Recently, we developed a method (Amadei et al., J. Biomol. Str. Dyn. 13: 615-626; de Groot et al., J. Biomol. Str. Dyn. 13: 741-751, 1996) to obtain an extended sampling of the configurational space of proteins, using an adapted form of molecular dynamics (MD) simulations, based on the essential dynamics (ED) (Amadei et al., Proteins 17:412-425, 1993) method. In the present study, this ED sampling technique is applied to the histidine-containing phosphocarrier protein HPr from Escherichia coli. We find a cluster of conformations that is an order of magnitude larger than that found for a usual MD simulation of comparable length. The structures in this cluster are geometrically and energetically comparable to NMR structures. Moreover, on average, this large cluster satisfies nearly all NMR-derived distance restraints.

Bacterial Proteins↗
PubMed1993

Detection of bluetongue virus in clinical samples by polymerase chain reaction.

A previously described bluetongue virus (BTV) serogroup polymerase chain reaction (PCR) assay was applied to clinical samples. The sensitivity of the BTV serogroup PCR was increased by the use of non-radioactive chemiluminescent hybridization. Unfractionated whole blood samples from rams experimentally inoculated with cell culture-adapted BTV-11 UC-8 were analyzed by virus isolation (VI) on Vero cells and PCR. VI and PCR were in agreement, with the exception of 3 blood samples that were VI negative and PCR positive. In semen spiked with BTV-11 UC-8, PCR detected as little as 1.6 x 10(2) plaque-forming units of BTV/ml of semen. BTV in the spleen of a sheep submitted for necropsy for suspect BTV infection was detected by both PCR and VI in embryonated chicken eggs. BTV PCR with nonradioactive chemiluminescent hybridization resulted in a level of sensitivity comparable to that of VI and likely more sensitive than VI on Vero cells for blood. This BTV PCR has great promise for rapid, sensitive, and specific detection of active BTV infection in a variety of clinical samples.

Animals↗
PubMed1999

Analytical characterization of electrochemical biosensor test strips for measurement of glucose in low-volume interstitial fluid samples.

BACKGROUND: Minimally invasive interstitial fluid (ISF) sampling and glucose measurement technologies were integrated into a hand-held device for diabetic glucose monitoring investigations. METHODS: Conventional electrochemical test strip technology (Bayer Glucometer Elite) was adapted to measure glucose in small (0.5-2.0 microL) samples of ISF. Test strip glucose measurements were performed on a commercial potentiostat and were compared to various reference glucose methodologies (YSI 2300 analyzer, microhexokinase procedure, Bayer Glucometer Elite). Characterizations of the integrated ISF sampling-glucose test strip design included accuracy and precision in various sample media (saline, ISF surrogates, diabetic ISF samples), sample volume dependence, test strip sterilization studies (electron beam, gamma irradiation), and diabetic ISF sampling and glucose measurements. RESULTS: Glucose measurements were free from significant media effects. Sample volume variations (0.6-3.2 microL) revealed only modest dependence of glucose measurement bias on sample volume (-1.5% per microliter). Sterilization treatments had only a minor impact on glucose response and test strip aging and no significant impact on interferent responses of the glucose test strips. Diabetic subject testing under minimum fasting conditions of at least 2 h with integrated ISF sampling and glucose measurement gave low ISF glucose measurement imprecision (CV, 4%) and mean glucose results that were indistinguishable from reference (microhexokinase) ISF glucose measurements and from capillary blood glucose measurements (Glucometer Elite). CONCLUSIONS: Conventional single-use, electrochemical glucose test strip and ISF collection technologies can be readily integrated to provide real-time ISF sampling and glucose measurements for diabetic monitoring applications.

Biosensing Techniques↗
PubMed1984

A psychometric study of the family adaptability and cohesion evaluation scales.

The Family Adaptability and Cohesion Evaluation Scales (FACES), a measure of family functioning, contains three scales: cohesion, adaptability, and social desirability. These were slightly modified (FACES-R) on the basis of pilot data and were administered to 42 clinic families (families seeking or receiving psychological services) and 206 nonclinic families. Support for the scales was found in high coefficient alpha reliabilities and similarity of the sample means and standard deviations to those of the standardization sample. However, there was little agreement among family members' scale scores. Therapists' ratings of cohesion and adaptability did not correlate with scale scores among clinic families. There was no difference between clinic and nonclinic samples on the cohesion or adaptability scales, although the social desirability scale did discriminate between groups. Factor analysis suggested that cohesion, adaptability, and social desirability cannot be clearly differentiated using this measure.

Adaptation, Psychological↗
PubMedDate not supplied

Tolerance of soil flagellates to increased NaCl levels.

The ability of heterotrophic flagellates to survive and adapt to increasing salinities was investigated in this study. Whole soil samples were subjected to salinities corresponding to marine conditions and clonal cultures were used to perform growth and adaptation experiments at a wide range of different salinities (0-50 ppm). More morphotypes tolerant to elevated NaCl levels were found in road verge soil that was heavily exposed to de-icing salt than in less exposed soils, though there were fewer tolerant than intolerant morphotypes in all soils examined. Heterotrophic flagellates isolated on a freshwater medium from a non-exposed soil were unable to thrive at salinities above 15 ppt, and showed reduced growth rates even at low salt salinities (1-5 ppt). The findings suggest that heterotrophic soil flagellates are less tolerant to NaCl than their aquatic relatives, possibly due to their long evolutionary history in soil, and support the idea that identical morphospecies may differ considerably with respect to physiology

Adaptation, Physiological↗
PubMed1994

[Adaptation of a measure of dysfunction-related illness: the Spanish version of Sickness Impact Profile].

BACKGROUND: The aim of the research was to adapt the Sickness Impact Profile (SIP) for their use in Spain. The Sickness Impact Profile is a questionnaire that measure the dysfunction related illness in 12 categories. It contain 136 items weighted by the relative importance in each category. In the present article we described the translation and the preliminary weighting process of each item and category. METHODS: In the translation we used the back-translation method by means of English-American and Spanish bilinguals. The items with equivalence B or C were discussed with a group of patients until to reach an agreement in the version. The scaling was carried out by 25 judges (health professionals). Following the same methodology as the original version, the judges firstly placed the relative values of each item in each category on an interval scale of 1 (minimal dysfunction) to 11 (maximal dysfunction) points; secondly the items most and least dysfunctional in each category were placed on a 1-15 interval scale (method of equal appearing intervals). RESULTS: In the translation process we identify 12 items with equivalence B or C. The results showed a high correlation between the values obtained by each judge and the mean values of the judges by item (0.64-0.81). The items were rated with a standard deviation of the mean of 1.91 and a standard deviation of the standard deviation of 0.52. The correlation between Spanish and American values was r = 0.84 (p < 0.001). CONCLUSIONS: Given the low number of non-equivalent items, the high agreement among the judges in the valuation of the items and the high correlations obtained between the Spanish and American weights, we conclude that the cross-cultural process have been satisfactory. The results should be to repeat in a sample of health consumers. The process of adaptation of the Spanish version will not finish until that the validity and reliability are similar to those of the original version.

Activities of Daily Living↗
PubMed1998

Optical high-precision three-dimensional position measurement system suitable for head motion tracking in frameless stereotactic radiosurgery.

Head motion is a significant source of therapy-effect degradation in frameless stereotactic radiosurgery (SRS). In this study, a three-dimensional (3-D) optical head motion measurement system and a coordinate transformation algorithm were used to track patient head motion. With this system, head motion in frameless SRS was carefully investigated with a precision of < 0.1 mm. Head motions without any restraint (three cases) and with a Laitinen adapter (four cases) were measured with a data sampling rate of once per second for 30 min. Positions of IR light emission diode markers attached to the head were analyzed by two statistical methods. From these data, mathematically simulated head motions were obtained in each of the three coordinate directions for nonrestraint and Laitinen-adapter SRS. The results show that segmenting a frameless SRS procedure into a sequence of short intervals and repeating registration of the target position for each interval is a good strategy for better therapy precision. This optical 3-D position measurement system is suitable for high-precision head motion tracking in frameless SRS.

Adult↗
PubMed2005

Point-based geometric deformable models for medical image segmentation.

Conventional level set based image segmentations are performed upon certain underlying grid/mesh structures for explicit spatial discretization of the problem and evolution domains. Such computational grids, however, lead to typically expensive and difficult grid refinement/remeshing problems whenever tradeoffs between time and precision are deemed necessary. In this paper, we present the idea of performing level set evolution in a point-based environment where the sampling location and density of the domains are adaptively determined by level set geometry and image information, thus rid of the needs for computational grids and the associated refinements. We have implemented the general geometric deformable models using this representation and computational strategy, including the incorporation of region-based prior information in both domain sampling and curve evolution processes, and have evaluated the performance of the method on synthetic data with ground truth and performed surface segmentation of brain structures from three-dimensional magnetic resonance images.

Algorithms↗
PubMed2005

Dimensions of cancer locus of control scale as predictors of psychological adjustment and survival in breast cancer patients.

The Cancer Locus of Control Scale, to investigate specific beliefs of control in cancer patients, was validated previously with an English-speaking population. This study tested the construct and concurrent validity of a 17-item French version of the scale and explored its relations with psychological adjustment and with adaptation assessed two years later. In a sample of 157 women diagnosed with a first breast cancer, the French version was administered along with the Body Image Questionnaire, the State-Trait Anxiety Inventory, the Perceived Stress Scale, the Social Support Questionnaire, and the Ways of Coping Checklist. A factor analysis performed on scores identified the three original factors: internal causal attribution, control over the course of the illness, and religious control. Internal causal attribution was associated with high scores for state and trait anxiety, negative body image, emotion-focused coping, and problem-focused coping. Control over the course of the cancer was positively associated with scores on both problem- and emotion-focused coping. Religious control was negatively associated with perceived stress. Emotional adjustment and quality of life were assessed in 59 of the 157 breast cancer patients two years after diagnosis and original testing. Hierarchical regression analyses indicated that internal causal attribution significantly predicted 38.1% of the variance in rated state anxiety. None of the dimensions of the Cancer Locus of Control Scale predicted the duration of survival measured two years later in 75 of the 157 patients.

Adaptation, Psychological↗
PubMed1995

Variability in adaptive response to low dose radiation in human blood lymphocytes: consistent results from chromosome aberrations and micronuclei.

The frequencies of chromosome aberrations and micronuclei were evaluated to assess the induction of adaptive response to low dose ionizing radiation in each of the blood samples collected from eight different individuals. Following stimulation with phytohemagglutinin, the cells were exposed to an adaptive dose of 1 cGy X-radiation at 24 hours and a challenge dose of 150 cGy gamma radiation at 48 hours. Lymphocytes were fixed at 54 hours to examine the incidence of chromosome aberrations and at 72 hours to examine the frequency of micronuclei in cytokinesis-blocked binucleated cells. Lymphocytes from five donors, i.e., "responders", exhibited the induction of adaptive response; their lymphocytes, which were pre-treated with 1 cGy had significantly fewer chromosome aberrations and micronuclei induced by the challenge dose of 150 cGy gamma radiation, as compared to the cells which did not receive the pre-treatment with 1 cGy. Such an induction of adaptive response was not observed in the remaining three donors, i.e., "non-responders"; the incidence of chromosome aberrations and micronuclei induced by the challenge dose of 150 cGy was not significantly different between the cells which were pre-exposed and un-exposed to 1 cGy. In all eight individuals, there was a strong positive correlation between the incidence of chromosome aberrations and micronuclei. Hence, whether or not an individual is a 'responder' or 'non-responder' could be assessed using either chromosome aberrations or micronuclei as the end-point. The overall pattern of response confirms the heterogeneity in adaptive response between individuals to ionizing radiation, which may in part be genetically controlled. Because of the simplicity of the technique and rapid assessment of the binucleated cells, we suggest the use of the micronucleus test as an alternative procedure in large scale population studies related to the adaptive response.

Adaptation, Physiological↗
PubMed2026

Genetic diversity, phylogenetic relationships, and marker development between Hydrangea serrata and H. macrophylla based on plastome and 45S nrDNA.

Ornamental hydrangeas (genus Hydrangea) are cultivated worldwide for their diverse flower colors and attractive morphology. Here, we assembled the complete plastid genome (plastome) and 45S nuclear ribosomal DNA (45S nrDNA) sequences of 22 individuals representing H. serrata, H. macrophylla, and related species (H. arborescens, H. paniculata, H. petiolaris, and H. hydrangeoides). The plastomes contained up to 2,344 single-nucleotide polymorphisms (SNPs) and 367 insertions/deletions (InDels) within the genus, whereas the assembled 45S nrDNA sequences showed 119 SNPs and 10 InDels. Phylogenetic analyses based on plastome and 45S nrDNA sequences clearly separated H. serrata and H. macrophylla from the other Hydrangea species. In the plastome-based tree, H. petiolaris was placed in the same clade as H. arborescens, whereas in the 45S nrDNA-based tree it showed a close relationship to H. hydrangeoides. The H. serrata and H. macrophylla samples were not always separated according to their species boundaries, as observed in samples Hse8-Hse12. Notably, one H. serrata sample (Hse8), collected from a wild mountainous region of Japan, exhibited a closer genetic relationship to H. macrophylla samples, indicating that cultivated hydrangeas may have originated from a specific wild lineage of H. serrata adapted to mountainous habitats. Using plastome-derived molecular markers, 66 Hydrangea samples were further classified into five groups, with Group II comprising both cultivated H. macrophylla and a subset of wild H. serrata samples, suggesting a close genetic affinity between this group and the ancestral gene pool of cultivated H. macrophylla. Based on these genomic resources, eight plastome-derived molecular markers were developed to differentiate cultivated hydrangeas from wild genotypes and to assess genetic diversity within H. serrata and H. macrophylla, providing practical tools for germplasm identification, breeding, and genetic resource management of Hydrangea species.

hydrangea↗
PubMed2005

Optimization of a simple, automatable extraction method to recover sufficient DNA from low copy number DNA samples for generation of short tandem repeat profiles.

AIM: To develop an automated, high throughput extraction protocol in order to produce database eligible profiles from fingerprints and other low copy number (LCN) DNA sources. METHODS: Extraction of either purified control DNA or buccal cells, for example, with commercial kits was compared to extraction with a simple digestion buffer and a subsequent concentration and purification. Results were evaluated based on the amount of DNA recovered and the completeness of the DNA profiles produced. RESULTS: Simple procedures with fewer steps were superior to commercial kits, such as DNA IQ (Promega, Madison, WI, USA) and QiaAmp (Qiagen, Valencia, CA, USA), and other protocols with many manipulations. The optimized protocol included a thirty-minute incubation with 0.01% SDS and proteinase K at 56 degrees C, followed by an incubation at 100 degrees C for 10 minutes. Concentration of the extract and removal of the SDS was accomplished with a Microcon 100 (Millipore, Bedford, MA, USA), which can be assembled into a 96 well plate, the Microcon-96 Retentate Assembly Plate (Millipore) for automation. The addition of 1 ng Poly A RNA to the Microcon significantly improved DNA recovery. CONCLUSION: A one-step sample digestion followed by sample concentration/purification minimized sample loss and maximized amplification input. Moreover, this methodology can be easily adapted for automation. Implementation of this protocol, due to the numerous potential sources of LCN DNA samples, will enhance the recovery of biological evidence from crime scenes and may be a source of database profiles.

Automation↗
PubMedDate not supplied

Nadolol: high-pressure liquid chromatographic methods for assay, racemate composition and related compounds.

High-pressure liquid chromatographic (HPLC) methods have been developed for the determination of drug content, racemate A and related compounds in nadolol raw materials. The method for drug content and related substances resolved seven related compounds and several unknown impurities from the drug. The minimum quantifiable levels were 0.05% or less for four of the seven related compounds and 0.3% or less for the remainder. Total impurities in eight raw material samples ranged from 0.06 to 0.96% and assay levels ranged from 98.7 to 101.0%. The method was adapted for the determination of nadolol racemate A by a change in mobile phase composition. One raw material sample contained less than 40% of racemate A. Two samples which had a granular appearance were variable in racemate A content. The methods were adapted for the determination of drug and racemate A in nadolol tablets. Drug content in three tablet samples was between 96.2 and 98.4% and racemate A content was about 52%.

Acetonitriles↗
PubMed1988

[Effect of adaptation to stress exposures on the cholino- and adrenoreactivity of the atria and their content of acetylcholine in rats with myocardial infarct].

The effect of left-ventricular myocardial infarction (MI) on cholino- and adrenoreactivity of an isolated right atrium and acetylcholine (AC) content of both atria was evaluated experimentally in Wistar rats, adapted or unadapted (control) to stress. In the control sample, 24-hour-long MI increased the chronotropic response to AC, while atrial endogenic AC dropped fourfold. Those changes were accompanied by no marked changes in pacemaker adrenoreactivity. Adaptation to stress reduced pacemaker choline reactivity without any significant effect on pacemaker adrenoreactivity or atrial AC. At the same time, adaptation largely prevented MI-induced increase in pacemaker choline reactivity and atrial AC drop. Increased pacemaker choline reactivity, seen in MI, enhances pacemaker sensitivity to cognition of ectopic excitation foci and, hence, cholinergic effects, that may promote the emergence of arrhythmia. Therefore, pacemaker resistance to cholinergic action, increasing in the course of adaptation, may be an important element of the protective antiarrhythmic effect of adaptation to stress in MI.

Acetylcholine↗
PubMed2007

Adaptive design method based on sum of p-values.

Bauer and Kohne proposed an adaptive design using Fisher's combination of independent p-values based on subsamples from different stages (Biometrics 1994; 50(4):1029-1041). Their method provides great flexibility in the selection of statistical methods for hypothesis testing of subsamples. However, the choices for the stopping boundaries are not flexible enough to meet practical needs (Biometrics 2001; 57(3): 886-891). In this paper, an adaptive design method is proposed using linear combination of the independent p-values. The method provides great flexibility in the selection of stopping boundaries and no numerical integration is required for the two-stage designs. The stopping boundaries and p-values can be calculated manually. The operating characteristics of the adaptive designs are studied using computer simulations with and without sample size adjustment. Examples are presented for superiority and non-inferiority trials with different endpoints (normal, binary, and survival) under different adaptations. The statistical efficiency of the proposed method is compared with other methods based on conditional power.

Data Interpretation, Statistical↗
PubMed2001

Social Orientation: Problem Behavior and Motivations Toward Interpersonal Problem Solving Among High Risk Adolescents.

A model of problematic adolescent behavior that expands current theories of social skill deficits in delinquent behavior to consider both social skills and orientation toward the use of adaptive skills was examined in an ethnically and socioeconomically diverse sample of 113 male and female adolescents. Adolescents were selected on the basis of moderate to serious risk for difficulties in social adaptation in order to focus on the population of youth most likely to be targeted by prevention efforts. Structural equation modeling was used to examine cross-sectional data using multiple informants (adolescents, peers, and parents) and multiple methods (performance test and self-report). Adolescent social orientation, as reflected in perceived problem solving effectiveness, identification with adult prosocial values, and self-efficacy expectations, exhibited a direct association to delinquent behavior and an indirect association to drug involvement mediated by demonstrated success in using problem solving skills. Results suggest that the utility of social skill theories of adolescent problem behaviors for informing preventive and remedial interventions can be enhanced by expanding them to consider adolescents' orientation toward using the skills they may already possess.

Journal Article↗
PubMed1993

Evaluation of an adaptive behaviour classification for mentally retarded adults.

Adaptive behaviour was assessed in a total of 119 mentally retarded adults by means of the Disability Assessment Schedule (DAS). According to a newly developed classification scheme, the level of handicap was graded on a four-step scale according to the subject's score in adaptive behaviour on the DAS; this was highly correlated both to the Coloured Progressive Matrices (CPM)-IQ (r = 0.75) and the Columbia Mental Maturity (CMM) Scale (r = 0.77). The DAS classification was associated with relevant neuropsychiatric variables. The findings indicate that the DAS classification represents a practicable way for assessing the degree of handicap in mentally retarded adults and could be especially valuable in cases where intelligence testing proves impossible, as was the case for 45% (CPM) and 39% (CMM) of the present sample.

Adaptation, Psychological↗