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[Cross-cultural adaptation, reliability and validity of the resilience scale].

This study describes the cross-cultural adaptation to Portuguese and the psychometric evaluation of the resilience scale developed by Wagnild & Young. The scale was adapted for a sample of students from public schools in São Gonçalo, Rio de Janeiro, Brazil. Data from the pilot study (203 students interviewed at two points in time) and from the entire study (977) are presented. The cross-cultural adaptation showed good results in the semantic equivalence for: general meaning (above 90.0%) and referential meaning (above 85.0%). Chronbach alpha was 0.85 in the pilot study and 0.80 in the total sample. Kappa between the two points in time was regular and moderate, and the intraclass correlation coefficient was 0.746 (p = 0.000). Factorial analysis indicated three non-homogeneous factors. Construct validity demonstrated direct and significant correlation with self-esteem, family supervision, life satisfaction, and social support. There was an inverse correlation with the scale that evaluates psychological violence.

Adaptation, Psychological↗

Screening yeast artificial chromosome libraries with robot-aided automation.

Screening of collections of yeast artificial chromosomes utilizing the polymerase chain reaction (PCR) requires large numbers of reactions in parallel. Four steps were implemented to reduce the labor involved: (a) The number of initial samples for DNA extractions was decreased by compressing libraries up to 12-fold. (b) DNA extraction from yeast clones was robot assisted. (c) A BIOMEK 1000 station was adapted to pipette samples for PCR assays. (d) Sample preparation was integrated with a temperature cycler constructed to carry out up to 576 reactions in six 8 x 12-well trays. The implementation of these steps increases the number of reactions per person per day by an order of magnitude. In tests with X-chromosome-specific probes, the robot-aided screening recovered all of the clones detected by slower manual methods.

Chromosomes, Artificial, Yeast↗

Rapid, sensitive determination of unchanged promethazine in biological material using a nitrogen-selective flame ionization detector. Identification of metabolites by gas chromatography-mass spectrometry.

A rapid, sensitive method has been developed to study the kinetics of unchanged promethazine (PM) in biological material using a nitrogen-selective flame ionization detector (N-FID). Unchanged PM is distinguished from its desmethyl metabolite. Sample clean-up of several biological fluids (rat plasma, blood, urine, liver and kidney homogenates) was studied and gas chromatographic (GC) conditions optimized. Usually 50 microliters-1.0 ml samples are extracted into n-heptane by shaking with NaOH, re-extracted into H2SO4 and again extracted into n-heptane by addition of NaOH. Finally, the organic phase is separated, concentrated under N2 and PM determined by N-FID. However, a rapid, single-step method requiring only NaOH extraction into n-heptane may be used whenever GC background permits. Imipramine is used as an internal standard for calibration by peak height ratios in the overall range 5--1500 ng PM per sample. Recovery of both methods is high (97--99%) but precision of the single-step method is lower (relative S.D. 10% versus 3--4%). Use of sample volumes up to 1 ml allows accurate determination of concentrations as low as 10 ng/g. Examples of applications to commonly used animal models employing PM are given and simple adaptation for clinical samples suggested.

Animals↗

Colour constancy in context: roles for local adaptation and levels of reference.

By determining the locations of boundaries between colour categories, we measured changes in the colour appearance of test-reflectances as a function of the simulated illumination. Test-reflectances were displayed against a variegated background of reflectance samples. Under prolonged adaptation to each illuminant, observers demonstrated a high degree of appearance-based colour constancy. By using backgrounds that consisted of chromatically biased sets of reflectances, we tested whether this stability depends on estimates of the illuminant's cone-coordinates based on simple scene statistics. The chromatic bias of the background had only a small effect on the classification of test materials. To compare the roles of spatially local and spatially extended estimation processes, we then (unknown to the observer) simulated different illuminants on the test and on the background. Observers continued to demonstrate reasonable colour constancy. To examine the relative roles of automatic adaptation and perceptual strategies, we reduced the duration of exposure to the test compared to exposure to the background (under the conflicting illuminant). The results suggest that mechanisms that preserve information across successive test-presentations (e.g. spatially local adaptation with a time course of a few seconds, and perceptual adjustments to levels of reference) are key determinants of the stability of colour appearance.

Adaptation, Ocular↗

Diagnosis of Ostreid herpesvirus 1 in fixed paraffin-embedded archival samples using PCR and in situ hybridisation.

In 1994, some of the high mortality episodes that affected oysters cultured in France were associated with herpesviral infections. Through histology analysis, however, viral presence could only be suspected and confirmation of histological diagnosis by transmission electron microscopy was performed in only a few cases. Subsequently, the characterisation and genome sequencing of Ostreid herpesvirus 1 (OsHV-1) made possible the development of specific molecular detection (PCR and in situ hybridisation (ISH)). Using both molecular tools, attempts were made to screen for OsHV-1 a number of fixed, paraffin-embedded oyster samples collected and processed in 1994. The aim was to compare these techniques and to estimate the accuracy of histology-based indication of viral infection. Existing DNA extraction protocols were adapted for oyster samples and two pairs of specific primers targeting small fragments (less than 200bp) were designed (C(9)/C(10) and B(4)/B(3)). The poor consistency observed between the results of PCR with both primer pairs was confirmed by statistical analysis. C(9)/C(10), which targets a repeated region of the OsHV-1 genome, appears to be the primer of choice for viral detection in archival samples. In situ hybridisation may furnish complementary information concerning the localisation of viral foci. Under certain conditions, retrospective examination of archival samples by molecular techniques may therefore provide valuable epidemiological data.

Animals↗

[Rapid diagnosis of rabies by the ELISA method. Its application in Madagascar: advantages and disadvantages].

ELISA technique in the rabies rapid diagnosis is compared with other methods used in the PASTEUR Institute of MADAGASCAR (immunofluorescence, mouse inoculation, and histopathology). The results of the comparative study of 80 samples of suspect animals show that ELISA sensibility is better than immunofluorescence one. Sensibility, specificity and viability of ELISA are comparable with those of the two confirmation techniques. In MADAGASCAR, ELISA is adapted to testing samples not conserved in good conditions, exposed to heat, after a big travelling time. It is to be hoped that samples are numerous to control rabies: in this condition price of ELISA is not expensive.

Animals↗

Bacterial adherence to biomaterials and tissue. The significance of its role in clinical sepsis.

The direct examination of tissue and biomaterials from prosthesis-related infections of twenty-five patients showed that the causative bacteria grew in glycocalyx-enclosed biofilms that were adherent to surfaces of biomaterials and tissues in 76 per cent. This high rate of recovery of adherent biofilm-mediated growth suggests that the process occurs commonly in the presence of a foreign body or biomaterial-related infection. Because of the adherent mode of growth of the infecting organisms, accurate microbiological sampling was difficult. The analysis of joint fluids or of swabs of excised tissue and of prosthetic surfaces often yielded only one species from what was a polymicrobial population based on electron microscopic studies. We adapted direct quantitative sampling methods from environmental microbiology in order to recover a large number of species from these infections, but comparison of the organisms isolated by these techniques with the morphological types that were seen by electron microscopy indicated that in some instances all bacterial components of the biofilms were still not being recovered.

Adhesiveness↗

Parent-infant relationship global assessment scale: a study of its predictive validity.

The Parent-Infant Relationship Global Assessment Scale (PIRGAS; Zero to Three, 1994) provides a continuously distributed scale of infant-parent relationship adaptation, raging from 'well-adapted' to 'dangerously impaired'. The present study examines the predictive validity of the PIRGAS in a high-risk sample by coding relationship adaptation level from a single sample of 10 min of unstructured free play between mothers and their 20-month-old infants and examining its relationship to subsequent interaction with mothers and behavior problems at 24 months. Relationship adaptation assessed reliably from observations of only 10 min of free play between mothers and their infants at 20 months of age using PIRGAS predicted subsequent mother- infant interaction in a laboratory based problem-solving paradigm (Crowell procedure) at 24 months and internalizing symptomatology of Child Behavior Checklist at age 24 months. These results contribute to the predictive validity of the PIRGAS as a measure of mother-infant relationship adaptation.

Adaptation, Psychological↗

Global cDNA amplification combined with real-time RT-PCR: accurate quantification of multiple human potassium channel genes at the single cell level.

We have developed a sensitive quantitative RT-PCR procedure suitable for the analysis of small samples, including single cells, and have used it to measure levels of potassium channel mRNAs in a panel of human tissues and small numbers of cells grown in culture. The method involves an initial global amplification of cDNA derived from all added polyadenylated mRNA followed by quantitative RT-PCR of individual genes using specific primers. In order to facilitate rapid and accurate processing of samples, we have adapted the approach to allow use of TaqMan real-time quantitative PCR. We demonstrate that the approach represents a major improvement over existing conventional and real-time quantitative PCR approaches, since it can be applied to samples equivalent to a single cell, is able to accurately measure expression levels equivalent to less than 1/100th copy/cell (one specific cDNA molecule present amongst 10(8) total cDNA molecules). Furthermore, since the initial step involves a global amplification of all expressed genes, a permanent cDNA archive is generated from each sample, which can be regenerated indefinitely for further expression analysis.

Breast↗

[Adaptation of the Multidimensional Trauma Recovery and Resilience (MTRR) questionnaire in a sample of Chilean mothers with a history of child abuse].

OBJECTIVE: Adaptation of the Multidimensional Trauma Recovery and Resilience (MTRR) in a Chilean sample. METHOD: Participants were 80 mothers drawn from two large metropolitan areas (Santiago and Temuco). Sample participants (in a case control design) were redivided in two groups: 40 mothers identified as physical abusers with history of physical child abuse and 40 mothers identified as nonabusers with history of physical child abuse. Groups were matched on 5 sociodemographic variables. Reliability analysis, item analysis, and group comparisons on the 8 scales of the instrument were performed. RESULTS: Interrater agreement level was .79 (Kendall's W coefficient) and the internal consistency as measured by Cronbach's alpha coefficient was .75. Twenty-five items (26.3%) significantly discriminated between the groups. Group comparison tests (Wilcoxon Rank-sum Test) also indicated that six of the eight domains discriminated between the groups. CONCLUSION: In our sample, the instrument has reliable results which discriminate between the studied groups. These preliminary findings support future work toward the development of a Chilean version of this instrument.

Case-Control Studies↗

[Hungarian adaptation of the Treatment Demand Indicator Protocol (TDI). Results of a multicenter study].

Accession to the European Union (EU) requires a revision of reporting system(s) and the adaptation of EU compliant measurement tools from the Hungarian side. In this study we try to monitor the Hungarian adaptation process of TDI regarding the European developments in this issue. The second goal of this study was to report on the reliability data of TDI which was assessed in Europe by our team first. 209 users of illicit drugs were sampled. The language adaptation needed a multi-stage translation process. The interrater and test retest reliability of TDI was found to be good. Inconsistency between related questions was not found. The reliability and validity indicators of the TDI in Hungary were acceptable. The protocol is easily applicable (5 minutes) and training is not needed.

Adolescent↗

The relationship between traditional and innovative sex-role adaptations and innovative sex-role adaptations and sexual satisfaction among a homogeneous sample of middle-aged Caucasian women.

This paper examines sexual experiences and satisfaction among a homogeneous sample of middle-aged, middle and upper socioeconomic status, Caucasian women. The hypothesis that women who occupy more traditional social roles on the traditional-innovative continuum would have greater sexual satisfaction is rejected. Relationships among a variety of indicators of sexual satisfaction and position on the innovative-traditional continuum indicated lack of consistent directionality or strong associations. Voluntary association memberships serendipitously emerged as a relatively strong indicator of social activities related to sexual satisfaction.

Employment↗

Brachytherapy dose-volume histogram computations using optimized stratified sampling methods.

A stratified sampling method for the efficient repeated computation of dose-volume histograms (DVHs) in brachytherapy is presented as used for anatomy based brachytherapy optimization methods. The aim of the method is to reduce the number of sampling points required for the calculation of DVHs for the body and the PTV. From the DVHs are derived the quantities such as Conformity Index COIN and COIN integrals. This is achieved by using partial uniform distributed sampling points with a density in each region obtained from a survey of the gradients or the variance of the dose distribution in these regions. The shape of the sampling regions is adapted to the patient anatomy and the shape and size of the implant. For the application of this method a single preprocessing step is necessary which requires only a few seconds. Ten clinical implants were used to study the appropriate number of sampling points, given a required accuracy for quantities such as cumulative DVHs, COIN indices and COIN integrals. We found that DVHs of very large tissue volumes surrounding the PTV, and also COIN distributions, can be obtained using a factor of 5-10 times smaller the number of sampling points in comparison with uniform distributed points.

Brachytherapy↗

Response to Skinner, et al. on "National personality characteristics: II. Adaption-innovation in Canadian, American, and British samples".

Skinner, et al. interpreted as significant the difference between means for Canadian men and women on Kirton's inventory and those for British and American samples. The means were similar to prior values. Skinner, et al.'s groups were large and composed of very unequal numbers of men and women, which factors could account for their interpretation. As reported, their analysis is insufficient to interpret very small mean variations as differences in national character.

Adult↗

Flexible designs by adaptive plans of generalized Pocock- and O'Brien-Fleming-type and by self-designing clinical trials.

Flexible designs are provided by adaptive planning of sample sizes as well as by introducing the weighted inverse normal combining method and the generalized inverse chi-square combining method in the context of conducting trials consecutively step by step. These general combining methods allow quite different weighting of sequential study parts, also in a completely adaptive way, based on full information from unblinded data in previously performed stages. So, in reviewing some basic developments of flexible designing, we consider a generalizing approach to group sequentially performed clinical trials of Pocock-type, of O'Brien-Fleming-type, and of Self-designing-type. A clinical trial may be originally planned either to show non-inferiority or superiority. The proposed flexible designs, however, allow in each interim analysis to change the planning from showing non-inferiority to showing superiority and vice versa. Several examples of clinical trials with normal and binary outcomes are worked out in detail. We demonstrate the practicable performance of the discussed approaches, confirmed in an extensive simulation study. Our flexible designing is a useful tool, provided that a priori information about parameters involved in the trial is not available or subject to uncertainty.

Clinical Trials as Topic↗

Tools for advance directives. American Health Information Management Association.

This issue of the Journal of AHIMA contains a Position Statement on advance directives. Here we have included several "tools" or helpful documents to support your organization's ongoing education regarding advance directives. First, we offer a "Sample Policy and Procedure" addressing the administrative process of advance directives. This sample policy was adapted from a policy shared by Jean Clark, RRA, operations director with Roper Hospital in Charleston, SC, and a director on the AHIMA Board of Directors. Do not automatically accept this policy and procedure for your organization. Instead, the health information management professional could use this sample to write your organization's own, specific policy and procedures that are consistent with your state's law and legal counsel's advice. The second article, "Advance Directives and the New Joint Commission Requirements," compares 1992 Joint Commission standards for Patient Rights and The Patient Self-Determination Act requirements. Selected sections from the Joint Commission chapter on Patient Rights are highlighted and comments added that contrast it with the act. "Common Questions and Answers Related to Advance Directives" is the third tool we offer. These questions and answers may be used for a patient education brochure or staff inservice education program outline. Again, information specific to your own state needs to be added. The fourth tool we offer is miniature "Sample Slides" or overhead transparency copy that can be enlarged and used for a presentation on the basics of advance directives for a community group for staff education. We thank Dee McLane, RRA, director, Medical Information Services at Self Memorial Hospital in Greenwood, SC, who developed these slides for presentations conducted at her hospital. We also thank Jeri Whitworth, RRA, who produced the graphics on these slides. Whitworth is a first year director on the AHIMA Board of Directors this year. Again you can use as is or consider these a model as you develop your own presentation geared for your specific audience. Last, but not least, we include samples of a "Living Will Declaration" and a "Durable Power of Attorney for Health Care" forms reprinted with permission from the American Association of Retired Persons (AARP). We include them here so you can examine the language of each type of advance directive. Copies for your organization should be requested from AARP at 1909 K Street NW, Washington, DC 20049, (202) 662-4895. Forms specific to each state are available from The Society for the Right to Die/Concern for Dying at 250 W. 57th Street, New York, NY 10107, (212) 246-6973. The requirement under The Patient Self-Determination Act became effective December 1, 1991, but the educational requirements of the act are meant to be ongoing. These "tools" are to help you continue to be a regular contributor to the educational process in your organization.

Advance Directives↗

Validation of candidate reference methods based on ion chromatography for determination of total sodium, potassium, calcium and magnesium in serum through comparison with flame atomic emission and absorption spectrometry.

OBJECTIVES: We report on the validation of candidate reference methods based on ion chromatography for the determination of total sodium, potassium, calcium, and magnesium in serum. The current study is a continuation of previous investigations in which we were able to show the potential of ion chromatography to serve as a reference method principle. The validation consisted of comparison of the ion chromatographic methods with generally recognized reference methods based on flame atomic emission (for sodium/ potassium) and absorption (for calcium/magnesium) spectrometry. METHODS: Sample preparation consisted of acidic dilution and pre-purification with reversed phase cartridges. Ion chromatography with suppressed conductivity was performed with polymeric stationary phases chemically modified with carboxylate and sulfonate functional groups for sodium/potassium and calcium/magnesium, respectively. Single-point calibration was used in combination with individual adaptation of serum sampling and diluting to give similar responses in samples and standards. In the study, more than 25 control sera were analyzed in parallel with the ion chromatographic methods and the traditional reference methods. The measurement protocol consisted of quadruplicate analysis of each sample per run, in 3 different runs. In each measurement series, internal quality control with certified reference materials from the National Institute of Standards and Technology and the Bureau Communautaire de Référence was applied. The performance criteria to fulfill were pre-defined (i.e., the maximum within-day and overall coefficient of variation, the confidence interval, the daily and overall deviation from the certified value and the maximum total analytical error). RESULTS: The comparison is presented as difference plot (i.e., % deviation of the results obtained with ion chromatography from those obtained with the respective traditional reference methods). The mean deviations were +0.9% for sodium, +1.0% for potassium, +/- 0.0% for calcium, and +0.1% for magnesium. With the exception of 2 values each for sodium and potassium, all deviations were within the limit of 2 times the allowed total analytical error. From the data obtained for internal quality control during the different measurement campaigns, we further estimated the long-term precision and accuracy of our methods. The overall coefficient of variation (respectively the bias) amounted to 0.7% (+0.1%) for sodium, 0.9% (-0.3%) for potassium, 1.3% (-0.1%) for calcium, and 1.0% (+/- 0.0%) for magnesium. CONCLUSION: From the precision and accuracy reached by our ion chromatographic methods, we conclude that they can be proposed as candidate reference methods for the determination of total sodium, potassium, calcium, and magnesium in serum.

Calcium↗

DAPAS, a computerised workplace for Digital Acquisition and Processing of Analog Signals, with up to two gigabytes data per registration.

A comprehensive and flexible arrangement for Digital long-term Acquisition and Processing of Analog Signals (DAPAS) has been developed. It is especially designed for neurophysiological laboratories and mainly based on IBM-compatible PC components. A/D converters are used, which allow sampling rates of up to 100 kHz (up to 16 bits, 1-16 channels). Signals are stored continuously on DOS devices and on a fast tape streamer, which uses standard video-8 tapes, and which is 2.8 times faster than DAT-based systems. As the recording speed is adapted to the sampling rate, one tape allows recording times of (uncompressed) data acquired at a sampling rate of 100 or 10 kHz of 6.8 and 68 h, respectively. Using a coprocessor-video device, recordings may be scrolled on- or off-line on the screen. In addition, up to eight multi-channel oscilloscopes are displayed simultaneously. DAPAS allows the use of a conventional matrix printer which can act as an inertia-free multi-pen recorder. Defined stored signals are recalled by means of a time code or textual markers. All sections of recordings lasting milliseconds to hours may be displayed within seconds. DAPAS supports export filters for further processing. Thus, this system replaces analog devices (multi-pen recorder, oscilloscope, data recorder), and enables quick, complete digital processing and analysis of neurophysiological data.

Action Potentials↗