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W Atkinson

Publications and source records attributed to W Atkinson.

At least 19 recordsLinked to original sources
PubMed2004

Food elimination based on IgG antibodies in irritable bowel syndrome: a randomised controlled trial.

BACKGROUND: Patients with irritable bowel syndrome (IBS) often feel they have some form of dietary intolerance and frequently try exclusion diets. Tests attempting to predict food sensitivity in IBS have been disappointing but none has utilised IgG antibodies. AIMS: To assess the therapeutic potential of dietary elimination based on the presence of IgG antibodies to food. PATIENTS: A total of 150 outpatients with IBS were randomised to receive, for three months, either a diet excluding all foods to which they had raised IgG antibodies (enzyme linked immunosorbant assay test) or a sham diet excluding the same number of foods but not those to which they had antibodies. METHODS: Primary outcome measures were change in IBS symptom severity and global rating scores. Non-colonic symptomatology, quality of life, and anxiety/depression were secondary outcomes. Intention to treat analysis was undertaken using a generalised linear model. RESULTS: After 12 weeks, the true diet resulted in a 10% greater reduction in symptom score than the sham diet (mean difference 39 (95% confidence intervals (CI) 5-72); p = 0.024) with this value increasing to 26% in fully compliant patients (difference 98 (95% CI 52-144); p<0.001). Global rating also significantly improved in the true diet group as a whole (p = 0.048, NNT = 9) and even more in compliant patients (p = 0.006, NNT = 2.5). All other outcomes showed trends favouring the true diet. Relaxing the diet led to a 24% greater deterioration in symptoms in those on the true diet (difference 52 (95% CI 18-88); p = 0.003). CONCLUSION: Food elimination based on IgG antibodies may be effective in reducing IBS symptoms and is worthy of further biomedical research.

Adolescent↗
PubMed2003

Increased platelet depleted plasma 5-hydroxytryptamine concentration following meal ingestion in symptomatic female subjects with diarrhoea predominant irritable bowel syndrome.

BACKGROUND: Meal ingestion is often associated with exacerbation of gastrointestinal symptoms in subjects with irritable bowel syndrome (IBS). Furthermore, recent preliminary data suggest that 5-hydroxytryptamine (5-HT) concentration in platelet poor plasma is elevated following meal ingestion in some subjects with diarrhoea predominant IBS (d-IBS) compared with healthy subjects, although it is not known whether this is related to postprandial symptomatology. AIM: To expand on previous data by evaluating a larger number of subjects but also to assess plasma 5-hydroxyindole acetic acid (5-HIAA) concentrations, 5-HT turnover, platelet 5-HT stores, and any relationship to symptomatology. METHODS: We assessed platelet depleted plasma 5-HT and 5-HIAA concentrations for two hours (60 minute intervals) under fasting conditions, and then for a further four hours (30 minute intervals) after a standard carbohydrate meal (457 kcal), together with fasting platelet 5-HT concentrations in 39 female subjects with d-IBS (aged 19-52 years; mean age 33) and 20 healthy female volunteers (aged 20-46 years, mean age 28). IBS symptomatology, in particular abdominal pain and bloating, and urgency to defecate were assessed throughout the study RESULTS: When related to fasting levels, there was no statistically significant difference in postprandial plasma 5-HT concentrations between d-IBS and healthy subjects. However, when fasting levels were not taken into consideration, d-IBS subjects exhibited higher postprandial plasma 5-HT concentrations compared with healthy subjects (p=0.040). Furthermore, d-IBS subjects who exhibited postprandial symptomatology had higher levels of postprandial plasma 5-HT, whether assessed with respect to fasting baseline levels (p=0.069) or not (p=0.047), compared with d-IBS subjects who did not report postprandial symptomatology. This appeared to be associated with a concomitant increase in plasma 5-HIAA (p=0.161) but reduction in turnover (p=0.058). Lastly, d-IBS subjects had higher platelet concentrations of 5-HT than healthy subjects (p=0.009). CONCLUSIONS: These data suggest that postprandial symptomatology may be associated with increased platelet depleted plasma 5-HT concentrations in female subjects with d-IBS. In addition, the presence of increased platelet stores of 5-HT may act as a useful marker for the diagnosis and management of d-IBS.

Adult↗
PubMed1999

Domestic aeroallergen exposures among infants in an English town.

A multicentre, prospective cohort study of childhood asthma was established in three European countries; the purpose of the project is the examination of factors which modify the relationship between allergen exposure in infant life and subsequent atopy and asthma. Dust samples were collected from the homes of 643 infants in a single town in the UK (the first cohort) and assayed for house dust mites (Der p 1) and cat allergen (Fel d 1) concentrations by enzyme-linked immunosorbent assay. A questionnaire with potential relevance to the development of atopy and asthma was completed. A wide variation in exposure to both allergens was observed. Carpeted, double-glazed or damp living rooms, and those sampled in the winter months, had higher levels of Der p 1, but these features did not predict Fel d 1 concentrations. Measures of high home occupancy were positively related to Der p 1 concentrations; and inversely with levels of Fel d 1, a finding which could not be explained by cat ownership. Homes in which one or more persons smoked had significantly lower concentrations of Der p 1, but not Fel d 1. There were no consistent differences in allergen levels between homes where one or more parent or sibling was either atopic or asthmatic. These findings indicate complex interactions among domestic, behavioural and seasonal factors and early allergen exposure in British children.

Air Pollution, Indoor↗
PubMed1999

Increased susceptibility to measles in infants in the United States.

BACKGROUND: Women born in the United States after measles vaccine licensure in 1963 transfer less measles antibody to their infants than do older women. This may result in increased susceptibility to measles among infants. OBJECTIVE: To determine the effect of maternal year of birth on the risk for measles in infants. METHODS: We enrolled 128 unvaccinated infants </=15 months of age who had documented exposure to measles from 1990 through 1992 in a retrospective cohort study. We interviewed their mothers by telephone to obtain demographic data, medical and vaccination history, and details of measles exposure and outcome. We used logistic regression analysis to estimate the effect of maternal year of birth. RESULTS: Infants whose mothers were born after 1963 had a measles attack rate of 33%, compared with 12% for infants of older mothers. In logistic regression analysis, the adjusted odds ratio for maternal year of birth (born after 1963) was 7.5 (95% confidence interval 1.8, 30.6). Other significant risk factors were older infant age, mothers who developed measles after delivery, and exposure within 2 days of the rash onset of the exposing case. CONCLUSIONS: Infants whose mothers were born after 1963 are more susceptible to measles than are infants of older mothers. An increasing proportion of infants born in the United States may be susceptible to measles. Infants at high risk of exposure to measles should be vaccinated at 12 months of age. Vaccination programs that reduce transmission of the measles virus in the general population reduce the risk of infant exposure to measles.

Age Distribution↗
PubMed1996

Measles outbreaks in the United States, 1987 through 1990.

BACKGROUND: During 1989 and 1990 reported measles cases in the United States increased 6- to 9-fold over the annual mean of 3000 between 1985 and 1988. To evaluate recent epidemiology we summarized measles outbreaks. METHODS: Confirmed measles cases reported to the National Notifiable Disease Surveillance System during 1987 through 1990 were analyzed. An outbreak was defined as > or = 5 epidemiologically linked cases. RESULTS: There were 815 outbreaks, accounting for 94% of the 52,846 cases reported. Similar to 1985 and 1986, 3 patterns of measles transmission during outbreaks were identified: (1) predominantly among unvaccinated pre-school age children < 5 years of age (38% of outbreaks); (2) predominantly among vaccinated school age children 5 to 17 years of age (40%); and (3) predominantly among unvaccinated and vaccinated post-school age persons > or = 18 years of age (22%). Most outbreaks were small (median, 12 cases), but very large outbreaks occurred (maximum size, 10,670). Although school age outbreaks (58%) predominated during 1987 and 1988, preschool age (40%) and post-school age (23%) outbreaks were more important during 1989 and 1990. CONCLUSIONS: Recent epidemiology suggests that to achieve elimination of measles, ACIP recommendations must be fully implemented, including (1) routine administration of the first dose of measles vaccine from 12 to 15 months of age and (2) use of a routine two-dose schedule to prevent school age and post-school age outbreaks.

Adolescent↗
PubMed1993

Platelet-derived growth factor B chain promoter contains a cis-acting fluid shear-stress-responsive element.

The endothelial lining of blood vessels is constantly exposed to fluid mechanical forces generated by flowing blood. In vitro application of fluid shear stresses to cultured endothelial cells influences the expression of multiple genes, as reflected by changes in their steady-state mRNA levels. We have utilized the B chain of platelet-derived growth factor (PDGF-B) as a model to investigate the mechanisms of shear-stress-induced gene regulation in cultured bovine aortic endothelial cells (BAECs). Northern blot analysis revealed elevated endogenous PDGF-B transcript levels in BAECs, after exposure to a physiological level of laminar shear stress (10 dynes/cm2; 1 dyne = 100 mN) for 4 h. A transfected reporter gene, consisting of a 1.3-kb fragment of the human PDGF-B promoter coupled to chloramphenicol acetyltransferase (CAT), indicated a direct effect on transcriptional activity. Transfection of a series of PDGF-B-CAT deletion mutants led to the characterization of a cis-acting component within the PDGF-B promoter that was necessary for shear-stress responsiveness. In gel-shift assays, overlapping oligonucleotide probes of this region formed several protein-DNA complexes with nuclear extracts prepared from both static and shear-stressed BAECs. A 12-bp component (CTCTCAGAGACC) was identified that formed a distinct pattern of complexes with nuclear proteins extracted from shear-stressed BAECs. This shear-stress-responsive element does not encode binding sites for any known transcription factor but does contain a core binding sequence (GAGACC), as defined by deletion mutation in gel-shift assays. Interestingly, this putative transcription factor binding site is also present in the promoters of certain other endothelial genes, including tissue plasminogen activator, intercellular adhesion molecule 1, and transforming growth factor beta 1, that also are induced by shear stress. Thus, the expression of PDGF-B and other pathophysiologically relevant genes in vascular endothelium appears to be regulated, in part, by shear-stress-induced transcription factors interacting with a common promoter element.

Animals↗
PubMed1990

Barriers to vaccinating preschool children.

Immunization represents one of the most effective tools in preventive medicine. But despite what should be a universal practice, preschool children, particularly in the inner cities, are not being adequately vaccinated. The responsibility for low immunization levels does not rest solely with the parents. Major obstacles within the health care system provide disincentives to immunization. Local resource problems such as inadequate clinic staff, hours, and locations make immunizations difficult to obtain. When comprehensive care is not easily accessible (e.g., requiring appointments weeks or months in advance), policies which require immunization to take place only within such a setting are further barriers. Many opportunities for vaccination are lost when children interact with the health care system but do not receive all the immunizations they need. Policies must be changed to facilitate immunization and to take advantage of all health care visits to provide vaccines.

Chicago↗