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PubMed2001

A brief measure of intrinsic religiosity used with a sample of military veterans.

A brief, three-item measure of intrinsic religiosity adapted from Gorsuch and Venable (1983) was used with over 900 male and female Reserve Component veterans who had been serving in the military during the Persian Gulf War. In general, approximately two-thirds of the veterans indicated agreement or strong agreement with an internal commitment to their religious beliefs. Despite its brevity, the scale demonstrated adequate estimates of internal consistency reliability (alpha = .93). It was also found that the female veterans reported a significantly higher mean on intrinsic religiosity as measured by this scale than did the male veterans.

Adult↗
PubMed1980

Determination of urine and cerebrospinal fluid protein with the American Monitor KDA.

In turbidimetric measurements, true light absorbance is not measured but rather dispersion of light by particles in suspension causes a decrease in light energy to reach the detector. Reproducible, sensitive results can be obtained by controlling such parameters as timing, temperature, mixing of sample and reagents, and use of decrease wave-length. I have adapted two manual turbidimetric methods for the determination of the total protein in urine and cerebrospinal fluid to the American Monitor KDA. The method in precise and rapid, and correlates well with the two manual methods while using small sample and reagent volumes. The method is linear to at least 5.0 g/l.

Autoanalysis↗
PubMed2006

CO/FT regulatory module controls timing of flowering and seasonal growth cessation in trees.

Forest trees display a perennial growth behavior characterized by a multiple-year delay in flowering and, in temperate regions, an annual cycling between growth and dormancy. We show here that the CO/FT regulatory module, which controls flowering time in response to variations in daylength in annual plants, controls flowering in aspen trees. Unexpectedly, however, it also controls the short-day-induced growth cessation and bud set occurring in the fall. This regulatory mechanism can explain the ecogenetic variation in a highly adaptive trait: the critical daylength for growth cessation displayed by aspen trees sampled across a latitudinal gradient spanning northern Europe.

Adaptation, Physiological↗
PubMed2002

PCR-ELISA I: Application to simultaneous analysis of mixed bacterial samples composed of intestinal species.

Sixteen oligonucleotide identification probes, designed in this study or adapted from literature, were tested for a PCR-ELISA application to simultaneously detect under standardised conditions selected intestinal bacteria, lactobacilli and bifidobacteria. The level of specificity obtained with most of the probes fulfilled the set criteria. The lack of efficiency of PCR performed with the primers, proposed to be specific for the entire eubacteria domain, and compromises made in hybridisation conditions due to simultaneous usage of multiple probes reduced the sensitivity of the PCR-ELISA test. The method was, however, found to be suitable for detecting predominant members of the intestinal flora. Applicability of the PCR-ELISA test could be further widened using primers with a more restricted specificity in the PCR step, as was demonstrated for the detection of Bifidobacterium with genus-specific primers. Advantages of the PCR-ELISA method include convenient performance and the possibility to test rapidly large amounts of samples with a multitude of probes.

Bacteria↗
PubMed1980

Effect of high pressure on the absorption spectrum and isomeric composition of bacteriorhodopsin.

The effects of high pressure upon the absorption spectra and isomeric composition of the dark (bRD) and light adapted (bRL) forms of bacteriorhodopsin were examined. Pressure favors the 13-cis form of bacteriorhodopsin (bR13-cis). The equilibrium isomeric composition and absorption spectra of bacteriorhodopsin samples at a given pressure were the same starting from either light or dark adapted bacteriorhodopsin. From the effect of pressure on the equilibrium constant between bRall-trans in equilibrium bR13-cis in the dark, the molar volume change between bRall-trans and bR13-cis was found to be -7.8 +/- 3.2 ml/mol. This volume change suggests a difference in conformation between dark- and light-adapted bacteriorhodopsin, but the magnitude of the change is small, involving only a small number of the protein residues.

Bacteriorhodopsins↗
PubMed1997

Improved methods to measure end products of nitric oxide in biological fluids: nitrite, nitrate, and S-nitrosothiols.

The aim of this study was to compare and improve standard methods to determine nitrite (NO2-), nitrate (NO3-) and S-nitrosothiol (RSNO) levels in cell culture supernatants, sera, and urine. We modified the conventional Griess reaction by replacing sulfanilamide with dapsone (4,4'-diamino-diphenylsulfone) and compared the NO2- levels in our study samples with a commercially available NO2- assay kit. Our modification, along with ultrafiltration of the samples, resulted in an enhanced sensitivity to measure NO2- down to 0.2 microM. The detection limit was further improved to 0.02 microM when NO2- was identified by the fluorochrome 2,3-diaminonaphthalene (DAN). To measure the stable end product NO3- by the Griess reaction or the DAN method, this anion must be reduced to NO2-. We compared the capacity of bacterial nitrate reductase with the reducing metal cadmium to convert NO3- to NO2-. After reduction, NO2- levels were determined either by the DAN method or by our modified Griess reaction. We found that there was a high correlation (r2 = 0.998) in total NO2- concentrations in the study samples using both methods for reducing NO3- to NO2-. The simultaneous determination of NO2- and NO3- was achieved by using anion-exchange chromatography (HPLC; Polyspher IC AN-1 column). The detection limit of this assay for each anion is 0.5 microM, and it can be applied equally well to sera, urine, and culture media. We also adapted the DAN method to determine RSNO levels in our study samples. Using this approach, we were able to measure RSNO levels down to 0.15 microM. As result we discovered that RSNO levels were markedly increased in urine from septic patients and in supernatants from cytokine-stimulated human tumor cell lines. L-Citrulline, a coproduct of NO biosynthesis, was measured using a colorimetric assay with a sensitivity limit of 3.0 microM. Increased L-citrulline levels in media from cultured cells, but not in sera or urine, correlated with increased NO production. Although all methods studied were suitable for quantifying end products of NO in biological fluids and media, the use of bacterial reductase and the modified Griess reaction proved successful to provide the greatest sensitivity and linear range for routine measurements of NO2- and NO3-.

Body Fluids↗
PubMed2001

Abnormal Doppler velocimetry and blood flow volume in the middle cerebral artery in very severe intrauterine growth restriction: is the occurence of reversal of compensatory flow too late?

OBJECTIVES: To determine the time course of quantified volumetric flow and pulsatility index changes in the middle cerebral arteries of severe intrauterine growth restricted fetuses with absent or reversed end diastolic flow velocities (AREDFV) on umbilical artery Doppler with a view to defining the threshold for early intervention before the onset of reversal of adaptation. SETTING: Fetal growth clinic of a large UK teaching hospital. SAMPLE: Seventeen severe intrauterine growth restricted (AC < third centile for gestation and gender) fetuses with abnormal umbilical artery Doppler velocimetry and oligohydramnios (amniotic fluid index <third centile for gestation). METHODS: One to three daily Doppler velocimetry and quantified volume flow of the middle cerebral artery Doppler velocimetry of the umbilical arteries and daily cardiotocography. RESULTS: Reversal of adaptation occurred in eight fetuses, four of which ended as stillbirths and four as neonatal deaths. In two of these fetuses, this had already occurred before the diagnosis of intrauterine growth restriction. In the others, the onset was rapid and difficult to predict. Volume flow in the middle cerebral arteries decreased in those fetuses exhibiting reversal of adaptation but rose in the nine in which compensatory Doppler indices persisted. The decrease in volume flow occurred before the onset of reversal of adaptation in the pulsatility index. In the fetuses exhibiting reversal of adaptation, the rise in the pulsatility index was consistent over 48 hours compared with the physiological fluctuations in pulsatility index in some fetuses where the rise was only for 24 hours followed by a fall. Quantified volume flow fell in the fetuses before reversal of adaptation set-in. The umbilical artery Doppler indices fluctuated between absent and reversed end diastolic velocities within the same fetus irrespective of the changes in the middle cerebral artery Doppler indices. CONCLUSION: Reversal of adaptation is of sudden onset and is associated with poor prognosis. Predicting its occurrence on Doppler indices is difficult as the changes may be very rapid. However, volume flow changes appear to be slower and of earlier onset than the pulsatility index changes. This may therefore be a more useful tool in predicting imminent reversal of adaptation and therefore early delivery.

Adult↗
PubMed1990

System for acquisition and real-time processing of multidimensional slit-scan flow cytometric data.

The high-speed sampling requirements of multidimensional slit-scan signals (cell contours) have typically required custom hardware. This specialized hardware has often lacked the flexibility to adapt to varying instrument setups and experimental requirements. A hardware and software system capable of sampling multiple slit-scan cell contours at rates of up to 40 MHz with 10-bit resolution is described. It utilizes commercially available CAMAC transient recorders, a Digital Equipment Corp. PDP-11/83 computer, and custom hardware for signal conditioning and trigger generation. The modular design of the software system allows various hardware options with minimal additional coding. Real-time digital processing checks each cell contour for multiple peaks; extracts morphological features such as width, height, and area; accumulates gated histograms of these data; and optionally saves the derived data, selected contours, or both into list mode files on disk.

Cervix Uteri↗
PubMed2026

Pathogenic properties of myasthenia gravis AChR autoantibodies associate with clinical response to efgartigimod.

BACKGROUND: Efgartigimod, a neonatal Fc receptor (FcRn) blocker, effectively reduces total IgG, including pathogenic acetylcholine receptor (AChR) autoantibodies in myasthenia gravis (MG); however, clinical responses vary. To investigate this variability, we studied how efgartigimod impacts AChR-specific autoantibody profiles and associated pathogenic mechanisms, including complement activation, AChR internalisation and ACh-binding site blockade. METHODS: Serum samples (N=150) were sourced from 50 AChR autoantibody-positive generalised MG patients participating in the phase 3 ADAPT study, randomised to receive efgartigimod (N=40) or placebo (N=10) in cycles of 4-weekly infusions. Samples were collected at baseline, day 29 and day 57 during the first cycle. Live cell-based assays quantified AChR-specific IgG subclasses and isotypes and assessed their capacity to mediate pathomechanisms. RESULTS: Efgartigimod decreased all detectable AChR-specific IgG subclasses. At baseline, AChR autoantibody-mediated C3b deposition, AChR internalisation and ACh-binding site blockade were detected in 42 (84%), 41 (82%) and 10 (20%) patients, respectively. After 4-weekly infusions of efgartigimod, the magnitude of all three pathomechanisms was significantly decreased. However, the extent of this reduction varied across individuals. Double responders on both MG-activities of daily living and quantitative MG scores demonstrated a greater reduction in complement activity and AChR internalisation compared with patients who responded on only one score or were double non-responders. In addition, efgartigimod reduced IgG-dependent IgM binding to AChR. CONCLUSIONS: These findings suggest that clinical efficacy may be more closely associated with functional modulation of the AChR-specific autoantibodies than with their absolute quantity alone. These results support the evaluation of mechanistic pathway monitoring as a potential strategy to predict or guide efgartigimod treatment response.

Humans↗
PubMed1992

Adolescent coping behavior when confronted with a friend with AIDS.

The coping strategies employed by adolescents (n = 871) when presented with a hypothetical situation of a friend with AIDS were examined. Adolescents reported a wide range of imagined responses that were generally adaptive. Girls more than boys and distressed students more than nondistressed students were likely to endorse adaptive coping items. Comparison of the students with a separate sample (n = 472) that responded to a hypothetical situation of a suicidal peer revealed more distress in girls for the AIDS problem and more distress in boys for the suicide problem, contrary to expectations. Adolescents were more distressed and endorsed a wider variety of coping strategies in response to the AIDS scenario than to the suicide problem. Implications for care of adolescents dealing with these significant issues are discussed.

Acquired Immunodeficiency Syndrome↗
PubMed2005

Polyploidy, evolutionary opportunity, and crop adaptation.

The finding that even the smallest of plant genomes has incurred multiple genome-wide chromatin duplication events, some of which may predate the origins of the angiosperms and therefore shape all of flowering plant biology, adds new importance to the molecular analysis of polyploidization/diploidization cycles and their phenotypic consequences. Early clues as to the possible phenotypic consequences of polyploidy derive from recent QTL mapping efforts in a number of diverse crop plants of recent and well-defined polyploid origins. A small sampling examples of the role(s) of polyploidy in conferring crop adaptation from human needs include examples of (1) dosage effects of multiple alleles in autopolyploids, and (2) 'intergenomic heterosis' conferring novel traits or transgressive levels of existing traits, associated with merging divergent genomes in a common allopolyploid nucleus. A particularly interesting manifestation of #2 is the evolution of complementary alleles at corresponding ('homoeologous') loci in divergent polyploid taxa derived from a common ancestor. Burgeoning genomic data for both botanical models and major crops offer new avenues for investigation of the molecular and phenotypic consequences of polyploidy, promising new insights into the role of this important process in the evolution of botanical diversity.

Adaptation, Biological↗
PubMed2006

Evaluating genetic differentiation of Anopheles arabiensis in relation to larval habitats in Kenya.

Anopheles arabiensis, an important vector of malaria in sub-Saharan Africa shows great versatility in utilizing a broad range of larval habitats. Most studies on the population genetic structure of this species have focused on adult mosquitoes collected mainly indoors and have found populations within relatively short distances to be panmictic. Various authors suggested that the incipient speciation between the chromosomal forms of Anopheles gambiae s.s. in West Africa involved adaptation to different habitats of larvae. To investigate if similar process occurs in An. arabiensis, we analyzed samples from four different larval habitats alongside a sample of adult mosquitoes collected indoors at eight microsatellite loci. We tested the hypothesis that An. arabiensis is subdivided into populations that are adapted to exploit different larval habitats. Overall, the level of genetic differentiation among the larval subpopulations was low with the mean pairwise Fst estimate based on information from all the loci being 0.0232 (P=0.1691) although differentiation was only significant for comparisons between certain larval samples and the adult samples. In addition, there was strong evidence against subdivision among larvae when multilocus simultaneous assignment tests were used. These results do not provide sufficient support for the hypothesis that An. arabiensis is subdivided into subpopulations that specialize to exploit different larval habitats.

Animals↗
PubMed1996

Danish norms for the Harvard group scale of hypnotic susceptibility, form A.

Norms for a Danish adaptation of the Harvard Group Scale of Hypnotic Susceptibility, Form A (HGSHS:A) are presented. Four samples tested from 1988 to 1991 (n = 166, n = 54, n = 95, and n = 61) were pooled, resulting in an aggregate sample of 376 participants. The normative data were generally congruent with earlier normative studies with regard to score distribution, item difficulty levels, and reliability. Studies using the Danish adaptation of the HGSHS:A as a screening instrument have shown the predictive value of the instrument in a Danish context. Data for a comparable American sample of volunteers (n = 170) tested by the same hypnotist were included in the analysis. A comparison revealed a marked difference for the posthypnotic suggestion item, hinting that cultural differences between the Danish and American samples with regard to expectancies and attitudes toward hypnosis may play a role. Further studies comparing attitudes toward hypnosis across different cultural contexts are needed to clarify this issue.

Adult↗
PubMed1996

Participation in leisure activities by older adults after a stressful life event: the loss of a spouse.

This study aimed to establish if frequent participation in leisure activities helped widows and widowers adapt to widowhood, and to maintain lower stress levels. A small sample of sixty recently bereaved widows (n = 43) and widowers (n = 17) who were living in an Australian city were selected for the study. Their ages ranged from fifty to eight-four years with a mean age of sixty-four years. Each widow or widower was interviewed and provided responses to three scales measuring participation in leisure activities, adaptation to widowhood, and stress. Quantitative and qualitative research techniques were used to interpret the data. The leisure activities most frequently participated in by widows and widowers were found to be home based activities, involving social activities with family and friends. Greater participation in leisure activities was found to be negatively correlated with stress scores, suggesting an association between leisure participation and stress reduction for recently bereaved widows and widowers. However, the study failed to find any association between participation in leisure activities and adaptation after the death of a spouse. In addition, no significant differences were found in the age, gender, income, and type of employment of widows and widowers, although perceived health status was found to be a significant factor in helping to determine future participation in leisure activities.

Adaptation, Psychological↗
PubMed2004

Brief report: the adaptation of Project Northland for urban youth.

OBJECTIVE: Summarizes the research and intervention design of a new trial to evaluate an adaptation of Project Northland, a multicomponent, community-wide alcohol prevention program for culturally diverse youth living in a large city. The original Project Northland was successful in reducing alcohol use among a sample of mostly White, rural adolescents. METHODS: We highlight the steps taken to adapt the intervention strategies for culturally diverse inner-city youth, families, and neighborhoods. The research design is a randomized controlled trial to evaluate the effectiveness of the adapted Project Northland for reducing the early onset and prevalence of alcohol use among young urban adolescents. CONCLUSION: The information gained from this trial, including the process of adaptation of prevention strategies, will be beneficial for alcohol-use prevention efforts within diverse urban communities across the country.

Adolescent↗
PubMed1989

A framework for the adaptation of psychological questionnaires for epidemiological use: an example of the Bortner Type A scale.

A model for the systematic adaptation of psychological questionnaires for epidemiological use is presented. Application of the model is illustrated using variants of the Bortner Type A scale in a representative age/sex stratified sample of 256 persons. Through the application of the model the Bortner scale was adapted to compare the effects of scale direction, scale format and example position. Overall the Bortner scale was shown to provide robust measurement which was little affected by response rate, age, sex or by the adaptations of the scale. An association was found of sex with response rate. Interaction effects of sex and scale direction on mean Type A scores, and of example position and scale format on both response rate and Type A score variability were also found. In identifying critical aspects of questionnaire performance, and in providing a coherent framework for their interrelationship, the model acts as a guide to the systematic assessment of questionnaire performance. The use of this model will, therefore, facilitate greater confidence in the interpretation of questionnaire data in epidemiological studies.

Adult↗
PubMed2006

Effect of short-term, high-dose retinol on dark adaptation in aging and early age-related maculopathy.

PURPOSE: To examine the effect of a short course of high-dose retinol (preformed vitamin A) on dark adaptation in older adults with normal retinal health or early age-related maculopathy (ARM). METHODS: The study design was a randomized, double-masked, placebo-controlled experiment. Adults > or = 50 years of age whose fundus photographs for the eye to be tested psychophysically fell within steps 1 to 9 of the Age-Related Eye Disease Study (AREDS) Grading System were randomly assigned to a 30-day course of 50,000 IU oral retinol or a placebo. At baseline and 30-day follow-up, dark adaptation was tested and the Low Luminance Questionnaire (LLQ), an instrument for assessing difficulty with vision in reduced lighting, was administered. Primary outcomes of interest were rod- and cone-mediated parameters of dark adaptation, with scores on the LLQ's six subscales as secondary outcomes. RESULTS: The sample consisted of 104 participants with 52 each in the intervention and placebo groups. There were no group differences in baseline variables. At 30-days, the dark-adaptation parameters of cone time-constant, cone threshold, rod-cone break, and rod threshold did not differ. The retinol intervention group had significantly larger (i.e., steeper) rod slopes, indicating faster sensitivity recovery, than did the placebo group (P = 0.0419). There were no group differences in scores on the LLQ subscales driving, extreme lighting, emotional distress, general lighting, or peripheral vision. The retinol group had a higher score by five points on the mobility subscale compared with the placebo group (P = 0.0141). Those who had the most self-reported change on the mobility subscale at day 30 were more likely to have greater change in the speed of dark adaptation, as indicated by the rod slope parameter (r = 0.24, P = 0.0141). CONCLUSIONS: A short-term, high-dose course of retinol increased the rate of rod-mediated dark adaptation in older adults who were in the early phases of ARM or were exhibiting normal retinal aging. These results are consistent with the hypothesis that depositions and other structural changes in the retinal pigment epithelium and Bruch's membrane in aging and early ARM cause a localized retinoid deficiency.

Aged↗
PubMed2005

Prevalence of botulinum neurotoxin C1 and its corresponding gene in environmental samples from low and high risk avian botulism areas.

Botulinum neurotoxin C1 (BoNt C1) and its corresponding gene were detected in seven aquatic habitats covering a range of low (LR) to high risk (HR) avian botulism outbreak areas during a study period of 10 months. Toxin and gene in sediment and avian faecal samples were analysed before (in situ) and after cultivation (in vitro) by a newly adapted ELISA, the common mouse bioassay and by a recently described nested PCR protocol. BoNt C1 gene fragments were detected in 74% and 83% of all investigated sediment samples by in situ PCR and in vitro PCR, respectively, at comparable frequencies in HR and LR areas. Similar high values were also observed for faecal samples. No BoNt C1 could be detected in the sediment in situ, while 53% and 56% of all cultivated samples contained BoNt C1 as detected in the mouse bioassay and the ELISA, respectively. The percentage of BoNt C1 positive cultivated samples was significantly higher (2-fold) in HR areas than in LR areas. Hence, our data clearly indicate an increased ratio of potentially BoNt C1 producing clostridia to BoNt C1 genes as the frequency or likelihood of botulinum epizootics increases in the environment. In addition, the good correlation between the results from the ELISA and the mouse bioassay for all sediment and faecal samples (r=0.90, p<0.001, n=121) indicates a high potential for the ELISA to reduce/replace the mouse bioassay for the detection of BoNt C1 in environmental samples.

Animals↗