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Biomedical subjects

J J Ryan

Publications and source records attributed to J J Ryan.

At least 55 records · Page 3Linked to original sources
PubMed1998

Characterization of a mobile Stat6 activation motif in the human IL-4 receptor.

The IL-4R induces proliferation and gene expression through the use of conserved tyrosine residues located in growth and gene regulation domains, respectively. We demonstrate that residues surrounding these conserved tyrosines (juxtatyrosine residues) are essential for the proper activation of the signaling molecules IRS-2 and Stat6, as well as for IL-4-induced gene expression. Further, we found that the IL-4R gene regulation domain (amino acids 557-657) contains a tyrosine-based sequence (EAGYKAF) that can convey Stat6 DNA binding and gene expression activities to a minimally active IL-4R mutant, delta 557. Thus, this tyrosine-based sequence can function as a mobile Stat6 activation cassette. However, mutants bearing this sequence induced CD23 expression much less efficiently than did wild-type IL-4R, requiring 150-fold more IL-4 to reach maximal CD23 expression. Our results indicate the importance of juxtatyrosine residues in IL-4R signaling and argue for an essential role of extended domain structure in the recognition and function of juxtatyrosine sequences.

Adjuvants, Immunologic↗
PubMed1998

Research contributions of counseling psychologists to neuropsychology.

Research productivity of counseling psychologists with credentials in clinical neuropsychology were examined. Eighteen were ABPP/ABCN Diplomates. Division 40 Fellows, or both. They published an average of 3.06 (SD= 4.82; range = 0 to 20) neuropsychologically relevant, first-authored articles over the past 5 years. When counseling psychologists were compared to a random sample of ABPP/ABCN diplomates with doctoral degrees in other areas of psychology, no reliable differences emerged between the groups in age, research productivity, or number of years between graduation and receipt of the ABPP/ABCN diploma. Research contributions of neuropsychologists with degrees in counseling psychology are comparable to those of ABPP/ABCN diplomates who were trained in other areas of psychology (e.g., clinical, developmental, and physiological).

Authorship↗
PubMed1998

Cultural differences on three measures of dissociation in a substance abuse population.

Scores on three measures of dissociation were compared between 48 African American and 48 Caucasian men being treated for substance abuse at a VA Medical Center. The three assessment instruments included the Dissociative Experience Scale, the Questionnaire of Experiences of Dissociation, and the North Carolina Index of Dissociation. Groups were matched with respect to age, education, marital status, number of previous treatments, IQ, employment status, history of childhood abuse, and psychological discomfort. In each case, the African-American group scored higher, with statistical significance being achieved on two of the three instruments. Potential implications of these findings were discussed and future research was suggested.

Adult↗
PubMed1998

Recombinant alpha-chains of type IV collagen demonstrate that the amino terminal of the Goodpasture autoantigen is crucial for antibody recognition.

Goodpasture's disease, an autoimmune disorder causing severe glomerulonephritis and pulmonary haemorrhage, is characterized by antibodies to the glomerular basement membrane (GBM). The principal target antigen has been identified as the carboxyl terminal non-collagenous (NC1) domain of the alpha3-chain of type IV collagen. Anti-GBM antibodies appear to recognize one major epitope that is common to all patients, and is largely conformational. We have analysed antibody binding to recombinant alpha(IV)NC1 domains using a construct and expression system shown to produce correctly folded antigen that is strongly recognized by autoantibodies. In this system, as with the native antigen, alpha3(IV)NC1 was bound strongly by antibodies from all patients, whereas the closely related alpha1(IV) and alpha5(IV)NC1 domains, similarly expressed, showed no such binding. A series of chimeric NC1 domains, between human alpha3(IV) and alpha1(IV), and between human and rat alpha3(IV), were expressed as recombinant molecules, and were recognized by autoantibodies to varying degrees. Strong binding required the presence of human alpha3(IV) sequence in the amino terminal region of both sets of chimeric molecules. This work strongly suggests that the amino terminal of alpha3(IV)NC1 is critical for antibody recognition, whereas the carboxyl terminal end of alpha3(IV)NC1 has a less important role.

Animals↗
PubMed1998

Survey of Canadian human blood plasma for ochratoxin A.

Blood plasma samples collected from 144 healthy volunteers in 16 locations across Canada in 1994 were analysed for ochratoxin A (OTA). The method of analysis included cleanup by C18 solid phase extraction and immunoaffinity columns followed by liquid chromatography (LC) with fluorescence detection, which gave 86.5% (s.d. = 9.7) recovery (n = 31) of OTA (added at 2 ng/ml) with a detection limit of 0.15 ng/ml. The arithmetic mean concentration found in the plasma samples, corrected for volume of anticoagulant added, was 0.88 ng/ml with a standard deviation of 0.35 ng/ml and a range of 0.29-2.37 ng/ml. Confirmation of identity of OTA was by methyl ester formation for 65 samples and by LC-tandem mass spectrometry for 17 samples (some of which were included in pooled samples). Statistical analysis, by ANOVA of the log OTA plasma concentrations, showed a highly significant effect due to location in Canada (p = < 0.0001) but no effect due to age, sex or blood group of donors. The highest mean concentration was found in Winnipeg, significantly different (p = 0.05) by the Student-Newman-Keuls multiple range test from the lowest levels found in Toronto, Vancouver and Saint John.

Adult↗
PubMed1998

Sequence analysis of the 'Goodpasture antigen' of mammals.

BACKGROUND: Autoimmunity to the NC1 domain of the alpha3 chain of type IV collagen (alpha3(IV)NC1), the Goodpasture antigen, is the cause of spontaneous human antiglomerular basement membrane (anti-GBM) disease, and of anti-GBM nephritis in several animal models. METHODS: We have derived amino acid sequences from alpha3(IV)NC1 for a number of mammalian species (monkey, sheep, pig, dog, rabbit, and rat) by RT-PCR and cDNA cloning. The GBM of some species was studied comparatively for binding to Goodpasture autoantibodies. RESULTS: From this work and other data the sequences of nine mammalian species can be aligned. Regions and residues that may be functionally important are identified. Alpha3(IV)NC1 sequences were found to be less closely conserved across species than alpha1 and alpha2(IV)NC1, 91 to 99% in comparison to a minimum of 97% for alpha1, but these differences were unevenly distributed along the molecule. There was a particularly striking homology between rodent and human sequences in the carboxyl-terminal region. Binding of Goodpasture autoantibodies to rat alpha3(IV)NC1 was poor in comparison with other species. CONCLUSIONS: Comparison of sequences and binding casts doubt on the importance of the carboxyl-terminal region for antibody binding, a region identified as a potential major epitope in previous studies. Sequence comparisons suggest possible reasons for the nephritogenicity of alpha3(IV)NC1 in active models of anti-GBM disease.

Amino Acid Sequence↗
PubMed1998

Characteristics of APA Division 40 Fellows and ABPP Diplomates in clinical neuropsychology.

Diplomate and Fellow status in clinical neuropsychology reflect professional competency and a record of significant contributions to the field. This present study provides a snapshot of the pathways to these distinctions and focuses on the educational history and demographic description of ABPP Diplomates and APA Division 40 Fellows. Identification of degree-granting institutions of these psychologists provides distal outcome data for training programs. Both credentials were identified as midcareer markers, as attainment of either required over 12 years of postdoctoral experiences. The pool of Fellows is significantly older than the Diplomates, but these data are confounded as 53 individuals hold both a diploma and Fellow status. Women were underrepresented in both groups. In regard to degree specialty, clinical psychology was the most prevalent degree program represented; however, the groups appear to be permeable to psychologists who received formal training in other subspecialties.

Adult↗
PubMed1998

Utility of the seven subtest WAIS-R short form in a female sample with brain damage.

We examined the accuracy of the WAIS-R seven subtest short form (Ward, 1990) for predicting IQs of 130 females with brain damage or dysfunction. Means for age, education, and FSIQ were 44.37 years (SD = 18.46), 12.74 years (SD = 2.42), and 87.64 (SD = 13.62). Results indicated that 93%, 84%, and 93% of short form estimated VIQs, PIQs, and FSIQs were within +/-5 points of their actual WAIS-R scores. In terms of Wechsler's (1981) seven category intelligence classification, levels of agreement were 83%, 72%, and 82% for the Verbal, Performance, and Full scales, respectively. These findings support the use of the seven subtest short form with brain-damaged women when time is at a premium and only a general estimate of intellectual functioning is required.

Adult↗
PubMed1998

Continuous Visual Memory Test performance in healthy persons 60 to 94 years of age.

Performance of elderly subjects on the Continuous Visual Memory Test (CVMT) was examined in a sample of neurologically normal adults (74 males and 103 females). Means for age and education were 71.20 years (SD = 6.02) and 14.77 years (SD = 2.48). Results revealed that the recommended impairment cut-off scores provided in the CVMT manual did not generalize to the current sample with 8% to 50% of healthy elderly persons falling within the impaired range. Therefore, the current sample was used to provide updated preliminary elderly normative data for the CVMT.

Journal Article↗
PubMed1998

Test-retest stability of the Continuous Visual Memory Test in elderly persons.

Ninety-two normal elderly persons were administered the Continuous Visual Memory Test (CVMT) on two occasions an average of 1.1 years apart. Means for age and education were 69.02 years (SD = 5.79) and 14.80 years (SD = 2.64), respectively. Stability coefficients were.49 on the Total score,.44 on d-prime, and.48 on Delayed Recognition. D-Prime and Delayed Recognition scores demonstrated significant change on retest. To assist clinicians in the process of detecting meaningful change on retest, standard error of difference values and 90% cut-off scores were provided.

Journal Article↗
PubMed1997

Estimating premorbid WAIS-R intelligence in the elderly: an extension and cross validation of new regression equations.

Recently developed equations that combine WAIS-R subtests and demographic information to estimate premorbid intelligence were evaluated in persons 75 years and older. The equations underestimated the obtained IQs of elderly persons. Therefore, new equations were developed using the old age WAIS-R standardization sample. The new equations cross-validated well and demonstrated adequate ability to detect possible intellectual deterioration in a brain damaged sample. The demographic formulas of Barona, Reynolds, and Chastain worked as well as the new equations in suggesting possible deterioration in a sample of elderly persons with chronic and diffuse cognitive impairment.

Aged↗
PubMed1997

Comparison of NART and Barona demographic equation premorbid IQ estimates in Alzheimer's disease.

Two methods of estimating premorbid WAIS-R intelligence were compared in matched samples of normal and AD persons. The NART and Barona 1984 demographic equations accurately predicted the IQs of the normal group and overestimated the IQs of the AD subjects. When the AD group was divided into mild and moderately impaired subgroups, the more severely demented subjects displayed lower WAIS-R IQs and NART estimated IQs, revealing that NART performance is sensitive to dementia severity. However, the NART estimated IQs for the mild and moderately impaired AD subgroups were larger than the WAIS-R IQs, suggesting that while the NART is sensitive to dementia severity, it may still provide relevant clinical information.

Aged↗
PubMed1997

The Neurobehavioral Cognitive Status Examination: accuracy of the "screen-metric" approach in a clinical sample.

This study assessed the accuracy of the "screen" versus "metric" portions of eight subtests of the Neurobehavioral Cognitive Status Examination (NCSE). As part of a routine hospital assessment, 95 male patients were administered both portions of the instrument regardless of outcome on the screen. Results indicate that the screen items of some of the NCSE subtests produced a relatively high false negative rate, where the screen was passed, but the metric was failed. It is recommended that all items of the subtests be administered to more fully assess each domain and, therefore, reduce the probability of overlooking significant deficits.

Aged↗
PubMed1997

Blood serum levels of PCBs and PCDFs in Yucheng women 14 years after exposure to a toxic rice oil.

In 1979, a mass poisoning of more than 2000 people occurred in central Taiwan due to consumption of rice-bran oil contaminated with PCBs and their heat-degraded byproducts. The incident was later referred to as Yucheng (oil disease). Serum samples from 56 women with the 1979 exposure were collected in February 1992 and analyzed for their contaminant content using sample enrichment and isotope dilution mass spectrometry. In most of the samples, levels of PCDFs and PCBs were detectable, and the median values of 2,3,4,7,8-PCDFs and 1,2,3,4,7,8-PCDFs were 1,030 and 2,220 ng/kg serum lipid, respectively. The median level of the total PCBs on a whole weight basis was 8,730 ng/kg. The PCB/PCDF concentrations in Yucheng women 14 years after the toxic exposure were still one to two orders of magnitude higher than controls. Concentrations of PCB levels in 1992 were positively correlated with the 1980-1981 measured PCB levels in these women and both PCBs and PCDFs were negatively correlated with the total duration when these women breast fed their children between 1979 and 1992. It is concluded that serum levels of congener-specific PCBs/PCDFs in exposed women are good indicators of previous exposure and may provide important information for more reliable estimation of dose-response relationship.

Benzofurans↗
PubMed1997

Test-retest stability of the California verbal learning test in older persons.

One hundred fifty-one healthy older persons were administered the California Verbal Learning Test (CVLT) on 2 occasions, an average of 1.30 years apart. Means for age and education were 69.63 years (SD = 6.46) and 14.91 years (SD = 2.54), respectively. Stability coefficients ranged from .24 on number of perseverations to .76 for both List A total recall and long-delay free recall. Only 5 CVLT scores demonstrated a significant change on retest, and the overall magnitude of improvement was small. To assist clinicians in the process of detecting significant change on retest, the authors provide standard error of difference values and 90% confidence intervals for 22 CVLT scores.

Aged↗
PubMed1997

California Verbal Learning Test: normative data for the elderly.

Overlapping age tables were developed, separately for males and females, to provide additional normative information for the California Verbal Learning Test (CVLT) and extend the normative data to persons older than 80 years of age. Participants were 92 males and 120 females with means for age and education of 70.58 years (SD = 6.98) and 14.92 years (SD = 2.56), respectively. Normative information was also provided for additional measures of retention rate and proportion of perseverations and intrusions. The clinical utility of these norms strongly depends on how closely a person matches the demographic characteristics of the normative group.

Aged↗
PubMed1997

Validity of quick short forms of the Wechsler Adult Intelligence Scale-Revised with brain-damaged patients.

The validities of 41 short forms of the Wechsler Adult Intelligence Scale-Revised that require 20 minutes or less to give were compared in a sample of 174 brain-damaged patients. Mean errors in predicting Full Scale IQs were computed for each subtest combination, and a short form efficiency index was calculated by correcting mean error for administration time. The three quick abbreviations proposed by Kaufman (1990) proved to be among the more efficient predictors of Full Scale IQ, but a number of other short forms also performed well. The data provide psychometric information for selecting a quick measure of IQ that fits the needs, preferences, and time constraints of the neuropsychologist.

Journal Article↗