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Biomedical subjects

K Ross

Publications and source records attributed to K Ross.

At least 19 recordsLinked to original sources
PubMed1995

The prevalence and characteristics of fibromyalgia in the general population.

OBJECTIVE: To determine the prevalence and characteristics of fibromyalgia in the general population. METHODS: A random sample of 3,006 persons in Wichita, KS, were characterized according to the presence of no pain, non-widespread pain, and widespread pain. A subsample of 391 persons, including 193 with widespread pain, were examined and interviewed in detail. RESULTS: The prevalence of fibromyalgia was 2.0% (95% confidence interval [95% CI] 1.4, 2.7) for both sexes, 3.4% (95% CI 2.3, 4.6) for women, and 0.5% (95% CI 0.0, 1.0) for men. The prevalence of the syndrome increased with age, with highest values attained between 60 and 79 years (> 7.0% in women). Demographic, psychological, dolorimetry, and symptom factors were associated with fibromyalgia. CONCLUSION: Fibromyalgia is common in the population, and occurs often in older persons. Characteristic features of fibromyalgia--pain threshold and symptoms--are similar in community and clinic populations, but overall severity, pain, and functional disability are more severe in the clinic population.

Adult↗
PubMed1995

REM sleep deprivation alters dopamine D2 receptor binding in the rat frontal cortex.

REM sleep deprivation (RSD) of rats results in facilitation of dopaminergic behavior and an increase in striatal D2 receptor density. To determine whether RSD results in changes in D2 receptor in other brain regions, receptor affinity (Kd) and density (Bmax) were measured in the anteromediofrontal (AM), cingulate (CN), and sulcal cortex (SL) in four groups of rats: 1), RSD96 group (RSD for 96 h; small pedestal/water tank method), 2) RSD24 group (large pedestals for 72 h then small pedestals for 24 h), 3) tank control group (TC; large pedestals for 96 h), and 4) cage control group. In separate groups, ambulation was recorded for 30 min following treatments. Group RSD96 showed an increase in activity compared to TC, and TC was increased compared to CC (p < 0.05 for all). In group RSD24, the AM showed an increase in Bmax and Kd (p < 0.05), but there were no effects by RSD96. In the CN, Bmax and Kd were decreased by RSD96 (p < 0.05) but not RSD24. In the SL, Bmax was increased by RSD96, but not RSD24, whereas Kd was increased in both RSD groups (p < 0.05).

Animals↗
PubMed1995

Aspects of fibromyalgia in the general population: sex, pain threshold, and fibromyalgia symptoms.

OBJECTIVE: To investigate relationships between sex, pain threshold and fibromyalgia (FM) symptoms in the general population. METHODS: Data were obtained from a randomized populations survey of 3,006 persons in Wichita, KS and a subsample of 391 who completed a detailed interview and had an examination. Tender point counts, dolorimetry scores, clinical and psychological variables were measured. RESULTS: Dolorimetry scores were 2.04 kg/cm (1.42-2.66) lower in women than men, and women were almost 10 times more likely to have 11 tender points [OR 9.6 (2.00-46.3)] than men. Women are also more likely to have FM symptoms than men: "Pain all over," [OR 3.94 (1.34-11.38)], sleep disturbance [OR 3.06 (1.45-6.46)], fatigue [OR 4.52 (2.03-10.09)], and irritable bowel syndrome [OR 5.23 (1.83-14.96)]. Tender point counts are more correlated with FM symptoms than dolorimetry scores. CONCLUSION: Symptoms of FM are correlated with pain threshold in the general population, but tender point counts correlate better than dolorimetry. These 2 measures of pain threshold assay different but overlapping factors. Pain threshold is lower in women; and women have more FM symptoms. Decreased pain threshold correlates with all of the symptoms of FM, even in those who do not meet criteria for the syndrome. This suggests that decreased pain threshold, as measured by the tender point counts, is an intrinsically important aspect of patient distress, regardless of the extent and kind of concomitant disease; and that much can be learned about patients by employing this examination.

Disability Evaluation↗
PubMed1994

Parents' and children's ratings of sleep behavior, excitement, and tiredness: a 10-week longitudinal study.

In a 10-week longitudinal study, 29 parents and their children kept daily records of the children's sleep behaviors, excitement levels, and tiredness levels. Although the hypothesized increase in sleep behaviors such as sleepwalking and restlessness during the week of Christmas did not occur, children rated as more excitable by their parents and themselves exhibited a higher frequency of sleep behaviors. Positive associations were also found between averaged tiredness ratings and sleep scores. The results support previous findings of an association between arousal characteristics of children and their sleep behavior. Moderate validity coefficients were obtained for parents' and children's ratings of excitement, tiredness, and nocturnal waking.

Arousal↗
PubMed1994

Illuminating dissertation supervision through reflection.

This paper describes a small research study designed to explore the role of the dissertation supervisor and to examine the potential of using reflection as a tool for learning and for enhancing professional educational practice. The authors met to discuss and reflect upon the processes of supervision and the role of the supervisor throughout the period of supervising three dissertation students. Each author maintained individual reflective written accounts of supervisory meetings with students. These accounts and the transcribed tape-recordings of the group meetings provided two sets of data which were analysed using qualitative techniques. From the data analysis the authors were able to identify various phases in dissertation supervision--partnership; setting the learning contract; signposting; ownership of the dissertation; letting go; the rush at the end; maintaining the balance--and also contextual issues of humanness; time; and energy, which were needed to sustain the supervisory processes. The role of the dissertation supervisor was illuminated and the potential of using reflection as a tool for developing professional educational practice was realized. The importance of constructive support while engaged in processes of reflection cannot be underestimated.

Academic Dissertations as Topic↗
PubMed1993

Effects of rapid eye movement sleep deprivation on the properties of striatal dopaminergic system.

Using the water tank procedure, we have examined the effects of rapid eye movement (REM) sleep deprivation and associated stress on the properties of striatal dopaminergic system. While stress decreased the number of D1 and D2 dopamine receptors, a combination of REM sleep deprivation attenuated the decrease. The ratio of D1 to D2 densities, however, increased on both the stress and REM sleep deprivation groups. In contrast, the number of dopamine uptake sites remained unchanged. The enhanced behavioral responses to dopaminergic stimulants after REM sleep deprivation are discussed.

Animals↗
PubMed1993

The prognosis of rheumatoid arthritis and undifferentiated polyarthritis syndrome in the clinic: a study of 1141 patients.

OBJECTIVE: To determine the prognosis of undifferentiated polyarthritis syndrome in the clinic compared with rheumatoid arthritis (RA). METHODS: We identified consecutive patients seen within the first 2 years of disease (and further subset into 6-month groups) diagnosed as having either RA or undifferentiated polyarthritis syndrome at the first clinic visit. Undifferentiated polyarthritis syndrome was characterized by clinical presentation, laboratory data, and American College of Rheumatology (ACR) 1958 and 1987 RA criteria. Followup evaluations were done to determine change in diagnosis, resolution of symptoms, and clinical remission of RA. RESULTS: Undifferentiated polyarthritis syndrome was more common in the clinic than RA (638 vs 503). Of patients with RA 7.6% were symptom free an average of 6.9 years after the first clinic visit. For those with disease onset between 0-6 months and 0-2 years, complete resolution of undifferentiated polyarthritis syndrome occurred in 57.9 and 53.9% of cases, including 46.1 and 35.6% meeting ACR 1987 criteria for RA. Latex positivity was the strongest predictor of failure to resolve subsequently (25.0 and 29.2% resolution) and the best predictor of development of RA (41.7 and 43.1%). CONCLUSIONS: Nonrheumatoid undifferentiated polyarthritis syndrome is more common in the clinic than RA. Undifferentiated polyarthritis syndrome resolves in more than half the cases, while RA remits in 7.6%. Finally, resolution of RA criteria positive undifferentiated polyarthritis syndrome occurs predominantly in those who are seronegative.

Adult↗
PubMed1992

Localization of dopamine D2 receptor protein in rat brain using polyclonal antibody.

The precise distribution of the dopamine type D2 receptor has been mapped for the first time in rat brain using an antibody to D2 receptor protein. Polyclonal antisera were collected from rabbits inoculated with an undecapeptide identical to residues 24-34 of the D2 protein sequence. Rat brain slices, 40 microns in thickness, were incubated with either primary antiserum, the antiserum plus free peptide antigen, or pre-immune serum. Antibody binding was visualized by peroxidase-antiperoxidase (PAP) reaction followed by light microscopy. PAP complex bound moderately-to-densely throughout the medial forebrain bundle, and was seen in more discrete regions in the midbrain, consistent with the binding of D2 radioligands. There were some unexpected results, namely in the cerebral cortex and nucleus accumbens, there were unexpectedly steep gradients in binding density, decreasing caudally; no binding was detected in the hippocampus or the substantia nigra pars reticulata. In all positive-staining regions examined, the antibody was highly localized to neuronal cell bodies, except in the frontal cortex where antibody was also evident on basilar dendrites. These data confirm that the polyclonal antibody recognized dopamine D2 receptor protein throughout the rat brain, and suggest that the D2 receptor is distributed more abundantly on somata than on cellular processes.

Animals↗
PubMed1992

Transforming growth factor-alpha is a potential mediator of estrogen action in the mouse uterus.

To better understand the role of peptide growth factors in sex steroid hormone-mediated growth of the female reproductive tract, the effect of estrogen on the expression of transforming growth factor-alpha (TGF alpha) in mouse uterus was investigated. Our results show that estrogen induces the expression of TGF alpha mRNA in the mouse uterus in a dose- and time-dependent manner. The up-regulation of TGF alpha transcripts occurs predominantly in uterine epithelial cells. RIA and Western blot analysis demonstrate that immunoreactive TGF alpha protein is secreted at high levels into mouse uterine luminal fluid after estrogen treatment. The induction of uterine TGF alpha mRNA is specific to estrogen; nonestrogenic steroids did not induce expression. Antibody specific to TGF alpha significantly reduces estrogen-mediated uterine growth, which supports the concept that TGF alpha is a mitogen for the reproductive tract. Analysis of TGF alpha/EGF receptors by binding, affinity labeling, and phosphorylation studies indicates that functional receptors are present in the mouse uterus after estrogen exposure. Thus, our data support a physiological role for TGF alpha and its receptor pathway in the female mouse reproductive tract.

Animals↗
PubMed1991

Glucose analogue inhibitors of glycogen phosphorylase: the design of potential drugs for diabetes.

The T-state crystal structure of the glucose-phosphorylase b complex has been used as a model for the design of glucose analogue inhibitors that may be effective in the regulation of blood glucose levels. Modeling studies indicated room for additional atoms attached at the C1-beta position of glucose and some scope for additional atoms at the C1-alpha position. Kinetic parameters were determined for alpha-D-glucose: Ki = 1.7 mM, Hill coefficient n = 1.5, and alpha (synergism with caffeine) = 0.2. For beta-D-glucose, Ki = 7.4 mM, n = 1.5, and alpha = 0.4. More than 20 glucose analogues have been synthesized and tested in kinetic experiments. Most were less effective inhibitors than glucose itself and the best inhibitor was alpha-hydroxymethyl-1-deoxy-D-glucose (Ki = 1.5 mM, n = 1.3, alpha = 0.4). The binding of 14 glucose analogues to glycogen phosphorylase b in the crystal has been studied at 2.4-A resolution and the structure have been refined to crystallographic R values of less than 0.20. The kinetic and crystallographic studies have been combined to provide rationalizations for the apparent affinities of glucose and the analogues. The results show the discrimination against beta-D-glucose in favor of alpha-D-glucose is achieved by an additional hydrogen bond made in the alpha-glucose complex through water to a protein group and an unfavorable environment for a polar group in the beta pocket. The compound alpha-hydroxymethyl-1-deoxy-D-glucose has an affinity similar to that of glucose and makes a direct hydrogen bond to a protein group. Comparison of analogues with substituent atoms that have flexible geometry (e.g., 1-hydroxyethyl beta-D-glucoside) with those whose substituent atoms are more rigid (e.g., beta-azidomethyl-1-deoxyglucose or beta-cyanomethyl-1-deoxyglucose) indicates that although all three compounds make similar polar interactions with the enzyme, those with more rigid substituent groups are better inhibitors. In another example, alpha-azidomethyl-1-deoxyglucose was a poor inhibitor. In the crystal structure the compound made several favorable interactions with the enzyme but bound in an unfavorable conformation, thus providing an explanation for its poor inhibition. Attempts to utilize a contact to a buried aspartate group were partially successful for a number of compounds (beta-aminoethyl, beta-mesylate, and beta-azidomethyl analogues). The beta pocket was shown to bind gentiobiose (6-O-beta-D-glucopyranosyl-D-glucose), indicating scope for binding of larger side groups for future studies.

Deoxyglucose↗
PubMed1991

Liver-specific gene expression: A-activator-binding site, a promoter module present in vitellogenin and acute-phase genes.

The A2 vitellogenin gene of Xenopus laevis, which is expressed liver specifically, contains an A-activator-binding site (AABS) that mediates high in vitro transcriptional activity in rat liver nuclear extracts. Footprint experiments with DNase I and gel retardation assays revealed the binding of several proteins to AABS. Using binding sites of known DNA-binding proteins as competitors in the gel retardation assay, we found that the transcription factor C/EBP and/or one of its "iso-binders" as well as LFB1/HNF1 bound AABS. These interactions were confirmed by in vitro transcription experiments using various oligonucleotides as competitors. However, saturating amounts of C/EBP- and LFB1/HNF1-binding sites as competitors only partially blocked AABS-mediated transcriptional activity. This finding implies that at least a third distinct transcription factor interacts with AABS. In vitro transcription experiments revealed that AABS was present not only in the closely related Xenopus A1 vitellogenin gene but also in acute-phase genes as a liver-specific regulatory element known to confer the interleukin-6 response. Both AABS and the interleukin-6 response element are promoter modules interacting with at least three distinct transcription factors, including C/EBP and LFB1/HNF1.

Acute-Phase Proteins↗
PubMed1990

BAP, a rat liver protein that activates transcription through a promoter element with similarity to the USF/MLTF binding site.

The vitellogenin genes of Xenopus are liver-specifically expressed. An in vitro transcription system derived from rat liver nuclei allowed us to define the cis-element BABS (B-activator binding site) in the promoter of the B1 vitellogenin gene. An oligonucleotide encompassing the region from -53 to -44 linked to a TATA box is sufficient for a tenfold increase of the transcriptional activity. Gel retardation assays with nuclear rat liver proteins reveal two DNA-protein complexes: Complex 1 can be competed by the USF/MLTF binding site of the adeno major late promoter whereas complex 2 is a distinct protein we refer to as BAP (B-activator protein). In vitro transcription experiments in the presence of USF/MLTF binding site as competitor show that BAP is an efficient transcription factor. Based on UV cross-linking we estimate that BAP has a molecular weight of 58 kd. Phosphatase treatment reveals that DNA binding of BAP requires phosphorylation. BABS is also present in the hepatitis B virus enhancer suggesting that it might play a role in the tumorigenic potential of the virus.

Animals↗
PubMed1990

Computer assisted instruction for autistic children.

Since the beginning of 1980, Computer-Assisted-Instruction (CAI) has been used systematically in special education. The use of computers in the treatment of autistic children is highly controversial and emotional among parents and professionals. Fears of reinforcing autistic withdrawal are often mixed with insecurity and dislike of new technologies. On the other hand, positive effects of CAI on learning and behaviour are reported by parents and published as single case studies. The following paper relates perception, motivation, communication and behaviour--characteristics of autistic children to features of computer-assisted learning. Preliminary findings support the benefit of the use of computer-technology for the management of behaviour and learning of autistic children. In 12 autistics, video-taped evaluations showed higher enthusiasm ratings in computer-sessions than personal instruction sessions. Single case-studies demonstrated a positive influence of CAI on autistic children's behaviour-problems (e.g. avoidance of eye contact, echolalia) as well as improved spontaneous communication and better learning of academics.

Adolescent↗
PubMed1988

A cell-specific activator in the Xenopus A2 vitellogenin gene: promoter elements functioning with rat liver nuclear extracts.

Transfection experiments using Xenopus vitellogenin A2 gene constructs allowed us to identify an activator which increases the activity of the thymidine kinase promoter. The activator is located between -121 and -87 of the A2 vitellogenin gene and is separated by a stretch of curved DNA from the estrogen-responsive DNA element at -331. The activator functions in a cell-specific manner, as it is active in human breast cancer cells (MCF-7) as well as hepatoma cells but not in fibroblasts or HeLa cells. The activator is composed of at least three elements: elements 1 and 2 which form a partial palindrome, function independently, but act synergistically when combined. Element 3 is not active on its own, but supports elements 1 and 2. A TATA box region derived from the Xenopus albumin gene is sufficient for the function of the activator. In vitro transcription experiments using rat liver nuclear extracts demonstrate that the activator interacts with transcription factors. These factors are distinct from those recognizing HP1, a regulatory element common to several genes specifically expressed in hepatocytes.

Animals↗