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Biomedical subjects

A Wilson

Publications and source records attributed to A Wilson.

At least 253 records · Page 14Linked to original sources
PubMed1994

Relation between infection with Helicobacter pylori and living conditions in childhood: evidence for person to person transmission in early life.

OBJECTIVES: To relate the prevalence of infection with Helicobacter pylori in adults to their living conditions in childhood to identify risk factors for infection. DESIGN: Prevalence study of IgG antibodies to H pylori (> 10 micrograms IgG/ml, determined by enzyme linked immunosorbent assay (ELISA)) and reported living conditions and other socioeconomic factors in childhood. SETTING: Three factories in Stoke on Trent. SUBJECTS: 471 male volunteers aged 18 to 65 years. MAIN OUTCOME MEASURES: Seroprevalence and variables in childhood. RESULTS: Seroprevalence of H pylori increased with age (22/74 (29.7%) at < 30 years v 29/46 (63%) at 55-65 years; P < 0.001 for trend) and was related to manual occupation (14/65 (21.5%) for non-manual v 162/406 (39.9%) for manual; P = 0.003). After data were adjusted for age and occupation subjects from large families, whose childhood homes were crowded or who regularly shared a bed in childhood, were significantly more likely to be seropositive (adjusted odds ratio (95% confidence interval) 2.15 (1.41 to 3.30) for crowding and 2.13 (1.38 to 3.30) for sharing a bed), but there was no relation with possession of a bathroom, inside toilet, refrigerator, or household pets in childhood. CONCLUSIONS: Close person to person contact in childhood is an important determinant of seroprevalence of H pylori in adulthood, suggesting that the infection is transmitted directly from one person to another and may be commonly acquired in early life.

Adolescent↗
PubMed1994

Longitudinal study of outcome of chronic fatigue syndrome.

OBJECTIVE: To examine the predictors of long term outcome for patients with the chronic fatigue syndrome. DESIGN: Cohort study. SUBJECTS: 139 subjects previously enrolled in two treatment trials; 103 (74%) were reassessed a mean of 3.2 years after start of the trials. SETTING: University hospital referral centre. MAIN OUTCOME MEASURES: Age at onset, duration of illness, psychological and immunological status at initial assessment. Ongoing symptom severity, levels of disability, and immunological function at follow up. RESULTS: 65 subjects had improved but only six reported no current symptoms. An alternative medical diagnosis had been made in two and psychiatric illness diagnosed in 20. The assignment of a primary psychiatric diagnosis at follow up and the strength of the belief that a physical disease process explained all symptoms at entry to the trials both predicted poor outcome. Age at onset of illness, duration of illness, neuroticism, premorbid psychiatric diagnoses, and cell mediated immune function did not predict outcome. CONCLUSION: Though most patients with the chronic fatigue syndrome improve, a substantial proportion remain functionally impaired. Psychological factors such as illness attitudes and coping style seem more important predictors of long term outcome than immunological or demographic variables.

Adaptation, Psychological↗
PubMed1994

Interleukins (IL)-1 and IL-2 control IL-2 receptor alpha and beta expression in immature thymocytes.

Functional high-affinity interleukin-2 receptors (IL-2R) contain three transmembrane proteins, IL-2R alpha, beta and gamma. We have investigated the expression of IL-2R alpha and beta genes in immature mouse thymocytes. Previous work has shown that during differentiation these cells transiently express IL-2R alpha on their surface. Stimulation of IL-2R alpha+ and IL-2R alpha- immature thymocytes with phorbol 12-myristate 13-acetate and calcium ionophore induces synthesis of IL-2R alpha and IL-2R beta mRNA. Most of this response depends on autocrine stimulation by IL-2. IL-1 synergizes with IL-2 to induce a 120-fold increase in IL-2R alpha mRNA and a 14-fold increase in IL-2R beta mRNA levels. A large proportion of the stimulated cells contains both transcripts. These interleukins do not induce any differentiation to more mature phenotypes. Collectively, these results show that IL-2 plays a major role in the regulation of IL-2R expression in normal immature thymocyte. We suggest that this response to interleukins may be part of a homeostatic mechanism to increase the production of immature thymocytes during stress.

Animals↗
PubMed1994

The murine interleukin-2 receptor gamma chain gene: organization, chromosomal localization and expression in the adult thymus.

Defects in the interleukin-2 receptor gamma (IL-2R gamma) chain in the man result in an X-linked severe combined immunodeficiency, SCIDX1, characterized by an absence of T-cell differentiation. This phenotype may result from pertubations in IL-2, IL-4-, IL-7- or IL-15-mediated signaling, as the IL-2R gamma chain forms an integral component of these receptor systems. We have isolated and characterized cDNA and genomic clones for the murine IL-2R gamma. The gene (Il2rg) is well conserved between mouse and man with respect to overall structure and size, and contains regions of high conservation in the promoter region as well. Il2rg maps to mouse X chromosome region 40, in a region of synteny with human Xq12-13.1. We have also explored the expression of the IL-2R gamma during thymocyte development. IL-2R gamma transcripts are detected in the earliest thymocyte precursor cells and persist throughout intrathymic development into the mature peripheral compartment. Genomic clones for the murine IL-2R gamma will allow for further studies on the regulation and function of this gene in vivo.

Amino Acid Sequence↗
PubMed1994

Muscarinic and nicotinic modulation of cortical acetylcholine release monitored by in vivo microdialysis in freely moving adult rats.

The aim of the present study was to investigate, using in vivo dialysis, the existence of muscarinic and nicotinic receptors controlling acetylcholine release in the cortex of freely behaving rats. Various muscarinic receptor antagonists, including the nonselective blocker atropine, and a variety of M2 drugs (AF-DX116, AF-DX384, AQ-RA 741) potently stimulated, in a concentration-dependent manner, the in vivo release of acetylcholine in the rat cortex. The effects of all these antagonists were long lasting. The nature of these putative muscarinic autoreceptors is likely of the pharmacologically defined M2 subtype on the basis of the high potency of the antagonists of the AF-DX series and the variability and shorter duration of action of the effects of the prototypic M1 blocker, pirenzepine. 4-DAMP, a purported M3 blocker, also potently stimulated in vivo cortical acetylcholine release, but this likely relates to its now established, rather limited selectivity for any given muscarinic receptor subtypes. Peripheral and central injections of nicotine also induced the in vivo release of acetylcholine in the rat cortex, albeit with a lower potency and shorter duration of action than muscarinic antagonists. Interestingly, the combination of a muscarinic antagonist, such as atropine, AF-DX 116, or AF-DX384, in the presence of nicotine, induced tremendous releases of cortical acetylcholine up to 8- to 10-fold over basal values. This is clearly more than a simply additive effect, and it reveals the great capacity of cortical cholinergic nerve terminals to synthesize and release acetylcholine. Optimal pharmacological manipulations of these putative muscarinic and nicotinic autoreceptors could thus be useful in disorders in which the activity of cholinergic inputs is decreased, such as in Alzheimer's disease.

Acetylcholine↗
PubMed1994

Self-report versus observer ratings of distress and pathology in Vietnam veterans with PTSD.

Few efforts have been made to examine the relationship between standard self-report measures and observer ratings of distress in veterans suffering from post-traumatic stress disorder (PTSD). In the present study correlations between self-report (verbal ratings and scores on the Brief Symptom Inventory) and observer ratings (scores on the Brief Hopkins Psychiatric Rating Scale) of pathology and distress were analyzed for 40 Vietnam combat veterans participating in a weekly outpatient PTSD therapy program. The relationship of these measures to the Mississippi PTSD scale and measures of combat exposure and duration was also examined. Results suggested that the self report and observer measures of distress were significantly correlated for this group. While written self report and observer ratings were correlated with scores on the Mississippi Scale, verbal self reports of distress were not. However, the verbal self reports of distress were most strongly related to reported combat exposure.

Adult↗
PubMed1994

The treatment of chronic fatigue syndrome: science and speculation.

The chronic fatigue syndrome (CFS) is a heterogeneous disorder characterized by fatigue, neuropsychiatric symptoms, and various other somatic complaints. Treatment studies to date reflect both the diversity of medical disciplines involved in the management of patients with CFS and the multiple pathophysiologic mechanisms proposed. There have been few attempts to study integrated treatment programs, and although several controlled studies have been reported, no treatment has been shown clearly to result in long-term benefit in the majority of patients. Good clinical care integrating medical and psychologic concepts, together with symptomatic management, may prevent significant secondary impairment in the majority of patients. Future treatment studies should examine differential response rates for possible subtypes of the disorder (eg, documented viral onset, concurrent clinical depression), evaluate the extent of any synergistic effects between therapies (ie, medical and psychologic), and employ a wide range of biologic and psychologic parameters as markers of treatment response.

Combined Modality Therapy↗
PubMed1994

The Western Sydney Stroke Risk in the Elderly Study. A 5-year prospective study.

Aging of the Australian population, as in other developed nations, will ensure that stroke remains one of the most important causes of death and disability. The Stroke Risk in the Elderly (SITE) study aims to measure prospectively the independent contribution of dietary, sociodemographic, blood lipid, blood pressure, and hemostatic factors to risk of stroke and other cardiovascular outcomes. The target population included all independently living men and women aged 65 years and over, residents in several retirement villages in western metropolitan Sydney, New South Wales, Australia. The study cohort consists of 225 men and 787 women, selected as a convenience sample from all eligible residents in the local government areas (LGAs) adjacent to Westmead Hospital. Participants attended a baseline session to complete dietary, life-style, medical, and sociodemographic questionnaires. Anthropomorphic variables and blood pressure were measured. Blood was taken for measurement of serum lipid, glucose, and hemostatic factors. Questionnaire results were compared with an age/sex-stratified, randomly selected sample drawn from the community (in the same LGAs), in order to quantify potential sampling and selection biases. The study cohort will be followed for a minimum of 5 years. The attendance rate of eligible residents for a baseline medical, dietary, life-style, and sociodemographic assessment was 72% for males and 69% for females. The study cohort was older, better educated, less ethnically diverse, and among women, less likely to have ever been married compared to people aged over 65 years in the comparison group. The baseline results suggest that hemostatic factors may be of importance in assessing risk of cardiovascular disease, (CVD), particularly in older men.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1994

Effect of lesions of the ventrolateral periaqueductal gray on the Pavlovian conditioned heart rate response in the rabbit.

The present experiment sought to evaluate the contribution of the ventrolateral periaqueductal gray to the expression of the conditioned bradycardic heart rate response in the rabbit. This response occurs in the presence of a fear-arousing conditioned stimulus. Lesions of the ventrolateral periaqueductal gray made after training failed to affect retention of the conditioned response. The results suggest that this region of the midbrain plays a nonessential role in the expression of the conditioned bradycardic response.

Animals↗
PubMed1994

Mediastinal large-cell lymphoma with sclerosis (MLCLS).

In a retrospective analysis encompassing a 14 year period (1978-92), 22 patients (age range 19-71, median 30 years) were identified as having mediastinal large-cell lymphoma with sclerosis on the basis of clinical and pathological features. At presentation, 15/22 had 'bulky' disease and 11/22 had evidence of superior vena caval obstruction. Thirteen patients had stage II disease (6,II; 7,IIE), nine presented with stage IV disease. Complete remission (CR) was achieved in only 4/22 patients with the initial adriamycin-containing regimen. 'Good partial remission' (no clinical evidence of disease, minimal abnormalities of uncertain significance on radiological investigation) was achieved in a further seven patients and 'poor partial remission' (a reduction in measurable disease > 50%) in four, giving an overall response rate of 15/22 (68%). One patient died within 48 h of arrival at the hospital; 16 of the 17 remaining patients in whom anything less than CR was achieved subsequently received additional, alternative treatment (one chemotherapy, six mediastinal radiotherapy, nine both treatment modalities) but in only 2/16 did this result in any further degree of response. With a median follow-up of 5 1/2 years, 10/22 patients remain well without progression between 6 months and 14 years (5/6 in whom CR was eventually achieved and 5/11 in whom only partial remission was ever documented). The seven patients in whom the initial treatment demonstrably failed have all died. These results suggest that a proportion of patients with this rare subtype of high-grade B-cell lymphoma may be cured by chemotherapy alone and that the presence of a residual mediastinal mass after treatment does not necessarily imply treatment failure. However, patients in whom the initial chemotherapy fails have a very grave prognosis.

Adult↗
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

Affectivity in cocaine and opiate abusers.

Psychoanalytic theorists concerned with substance abuse suggest that the affect tolerance and affect expression of addicts are impaired due to preverbal influences. However, psychoanalytic contributions have largely been limited to clinical speculations and case study reports. The present study investigated the hypotheses that opiate abusers will demonstrate more impaired affect tolerance and affect expression than cocaine abusers, and that both groups would appear more impaired than a sample of normals. To investigate these hypotheses, a recently developed instrument, the Epigenetic Assessment Rating System (EARS), was employed. The EARS empirically measures verbal and preverbal phenomena theoretically linked with stages of development. The subjects were 25 opiate, 25 cocaine abusers, and 25 normals, matched according to age, gender, and SES criteria. Results supported the hypotheses that opiate and cocaine abusers' affect tolerance and affect expression were significantly impaired as compared to normals. Although affect tolerance did not distinguish between opiate and cocaine abusers, affect expression did. Cocaine abusers were less impaired than opiate abusers by preverbal modes of affect expression, although under stress cocaine abusers regressed to similar states.

Adult↗
PubMed1994

Recovery after oral surgery with halothane, enflurane, isoflurane or propofol anaesthesia.

We have compared the recovery characteristics of four different techniques for maintenance of anaesthesia in 99 day-case patients admitted for oral surgery. All patients received propofol for induction of anaesthesia followed by halothane, enflurane, isoflurane or propofol infusion for maintenance of anaesthesia. Each patient was subjected to a battery of psychometric tests which included Spielberger state, trait, mood stress and mood arousal questionnaires, Maddox-Wing test and five-choice serial reaction time. All tests were performed before operation and at 0.5, 1, 2, 4, 24 and 48 h after operation. Performance in the reaction time test decreased significantly in the immediate postoperative period, returning almost to preoperative values by 4 h. However, only those patients who received enflurane or propofol had returned to their performance level before surgery by 4 h, although all four groups had achieved this target by 24 h. There was a further improvement in performance at 48 h. Anxiety and stress were high before surgery and decreased rapidly in the postoperative period. The Maddox-Wing test demonstrated a significant impairment in performance in the first 1 h after surgery, which returned to normal by discharge at 4 h. There were no significant differences between the four groups in these latter tests.

Adult↗
PubMed1994

Comparison of the effects of an organic and an inorganic form of selenium on a mammary carcinoma cell line.

The development of new compounds with greater cancer inhibitory activity and that are well tolerated continues to be a priority in chemoprevention research involving selenium. One compound, 1,-4-phenylene-bis(methylene)selenocyanate (p-XSC), is representative of a series of organoselenium compounds with these characteristics. In this study, the effects of p-XSC on a mouse mammary carcinoma cell line were compared to those of sodium selenite, which has been shown to be growth inhibitory. Treatment with p-XSC caused a 3- to 6-fold greater accumulation of selenium within cells than did treatment with equivalent amounts of selenite and cells were able to better tolerate higher cellular levels of selenium derived from p-XSC. Both compounds resulted in a dose-dependent reduction in cell number after 24 h of exposure. Selenite and p-XSC also caused a dose-dependent increase in cell death by apoptosis. This effect was observed within 5 h of treatment. The effect of p-XSC on apoptosis was more pronounced than that of selenite, especially at the 20 microM level of exposure. The induction of apoptosis by selenium compounds may partially account for their chemopreventive activity.

Animals↗
PubMed1994

Effects of age and gender on dichotic sentence identification.

There is converging evidence that aging causes a progressive decline in the central processing of speech and that this decline is greater for left-ear than for right-ear input. In the present paper we investigated, by means of a dichotic sentence identification paradigm, some parameters of the "left-ear effect." We analyzed the clinical records of 356 individuals, 203 males and 153 females, to whom the Dichotic Sentence Identification (DSI) Test had been administered as part of routine audiometric assessment. Subjects ranged in age from 9 to 91 yr. The DSI test was always carried out in two modes: free report (FR) and directed report (DR). In the FR mode the subject reported what was heard in both ears. In the DR mode the subject reported only what was heard in one precued ear. In half of the trials the right ear was precued, in the other half the left ear was precued. Findings confirm a progressively larger right-ear advantage, or left-ear deficit, with increasing age. We document this effect in both the FR and DR modes, then demonstrate that the effects cannot be attributed to interaural asymmetries in threshold sensitivity. Comparison of male and female data suggest a gender difference in the effect of age on the left-ear deficit. Males show a larger effect then females in both modes of test administration. Finally, we propose a model of dichotic listening performance that attempts to explain ear asymmetry as the linear combination of an auditory/structural component and a task-related/cognitive component. We then show how these hypothetical components change with age in the present sample.

Adolescent↗
PubMed1994

Medical audit and the role of the facilitator.

Describes how the Buckinghamshire Medical Audit Advisory Group have approached the introduction of medical audit in primary care. Outlines how the original facilitator model, which proved so successful in encouraging initiatives in coronary heart disease prevention, is now being used to encourage and promote quality initiatives using medical audit techniques. Explores use of the audit cycle and emphasizes the importance of teamwork in enabling change to occur. Outlines the special personal and professional skills required to work in the increasingly complex and dynamic arena of primary care, with a description of how the National Facilitator Development Project has taken on board these educational needs.

Administrative Personnel↗