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A Bolton

Publications and source records attributed to A Bolton.

At least 19 recordsLinked to original sources
PubMed2006

Assigning exposure to pesticides and solvents from self-reports collected by a computer assisted personal interview and expert assessment of job codes: the UK Adult Brain Tumour Study.

OBJECTIVES: To compare assignment of occupational pesticide and solvent exposure using self-reported data collected by a computer assisted personal interview (CAPI) with exposure based on expert assessment of job codes. To discuss the advantages and disadvantages of using a CAPI to collect individual occupational exposure data. METHODS: Between 2001 and 2004, 1495 participants were interviewed using a CAPI for a case-control study of adult brain tumours and acoustic neuromas. Two types of occupational data were collected: (1) a full history, including job title from which a job code was assigned from the Standard Occupational Classification; and (2) specific details on pesticide and solvent exposure reported by participants. Study members' experiences of using the CAPI were recorded and advantages and disadvantages summarised. RESULTS: Of 7192 jobs recorded, the prevalence of self-reported exposure was 1.3% for pesticides and 11.5% for solvents. Comparing this with exposure expertly assessed from job titles showed 53.6% and 45.8% concordance for pesticides and solvents respectively. Advantages of the CAPI include no data entry stage, automatic input validation, and a reduction in interviewer bias. Disadvantages include an adverse effect on study implementation as a consequence of resources required for programming and difficulties encountered with data management prior to analysis. CONCLUSIONS: Different methods of exposure assessment derive different exposure levels for pesticide and solvent exposure at work. Agreement between self-reported and expert assessment of exposure was greater for pesticides compared to solvents. The advantages of using a CAPI for the collection of complex data outweigh the disadvantages for interviewers and data quality but using such a method requires extra resources at the study outset.

Adolescent↗
PubMed2001

Deaths and injuries from house fires.

BACKGROUND: We sought to define the factors associated with house fires and related injuries by analyzing the data from population-based surveillance. METHODS: For 1991 through 1997, we linked the following data for Dallas: records from the fire department of all house fires (excluding fires in apartments and mobile homes), records of patients transported by ambulance, hospital admissions, and reports from the medical examiner of fatal injuries. RESULTS: There were 223 injuries (91 fatal and 132 nonfatal) from 7190 house fires, for a rate of 5.2 injured persons per 100,000 population per year. Rates of injury related to house fires were highest among blacks (relative risk, 2.8; 95 percent confidence interval, 2.1 to 3.6) and in people 65 years of age or older (relative risk, 2.6; 95 percent confidence interval, 1.9 to 3.5). Census tracts with low median incomes had the highest rates of injury related to house fires (relative risk as compared with census tracts with high median incomes, 8.1; 95 percent confidence interval, 2.5 to 32.0). The rate of injuries was higher for fires that began in bedrooms or living areas (relative risk, 3.7); that were started by heating equipment, smoking, or children playing with fire (relative risk, 2.6); or that occurred in houses built before 1980 (relative risk, 6.6). Injuries occurred more often in houses without functioning smoke detectors (relative risk, 1.5; 95 percent confidence interval, 1.0 to 2.4). The prevalence of functioning smoke detectors was lowest in houses in the census tracts with the lowest median incomes (P<0.001). CONCLUSIONS: Rates of injuries related to house fires are highest in elderly, minority, and low-income populations and in houses without functioning smoke detectors. Efforts to prevent injuries and deaths from house fires should target these populations.

Adolescent↗
PubMed2001

Identification of the acid phosphatase (acpA) gene homologues in pathogenic and non-pathogenic Burkholderia spp. facilitates TnphoA mutagenesis.

Burkholderia pseudomallei and Burkholderia mallei are pathogens responsible for disease in both humans and animals. Burkholderia thailandensis, while phylogenetically similar, is considered avirulent in comparison. These three species exhibit phosphatase activity when grown on media containing chromogenic substrates such as 5-bromo-4-chloro-3-indolyl phosphate (XP). Tn5-OT182 mutagenesis has been utilized to isolate mutants of B. pseudomallei and B. thailandensis unable to hydrolyse XP. Sequence analysis of these mutants revealed an ORF of 1734 nucleotides demonstrating a high degree of homology to the acpA gene product of Francisella tularensis. PCR primers were designed based on the B. pseudomallei acpA gene sequence and were used to amplify an acpA homologue from B. mallei. The predicted amino acid sequence of B. pseudomallei AcpA differed from those of the predicted B. thailandensis AcpA and B. mallei AcpA by 15 and 3 amino acids, respectively. Allelic exchange was used to construct DeltaacpA mutants in each of these Burkholderia spp. These mutants were shown to be devoid of phosphatase activity and have subsequently allowed for the implementation of phoA fusion transposon mutagenesis systems. Two such systems have been successfully utilized in Burkholderia spp. for the identification of several genes encoding exported proteins.

Acid Phosphatase↗
PubMed2001

Surface-expressed mig protein protects Streptococcus dysgalactiae against phagocytosis by bovine neutrophils.

The mig gene of Streptococcus dysgalactiae, a major bovine mastitis pathogen, encodes two plasma protein-binding receptors, alpha2-macroglobulin (alpha2-M) and immunoglobulin G (IgG). In this study, the mig gene from one S. dysgalactiae isolate was cloned and expressed in Escherichia coli. The IgG receptor region encoded by mig was conserved in 16 S. dysgalactiae strains. An isogenic mig mutant was constructed by allele replacement mutagenesis of the wild-type gene in S. dysgalactiae. The IgG-binding activity was lost in the mig mutant strain, whereas the alpha2-M receptor activity was still expressed but was detected only in the culture supernatant. In flow cytometry phagocytosis and bacterial-colony-counting bactericidal assays, the wild-type strain was found to be significantly more resistant to phagocytosis and killing by bovine neutrophils (PMNs) than the mig mutant strain when bacteria were preincubated with bovine serum. We therefore speculate that the Mig protein of S. dysgalactiae plays a role in virulence of the bacteria by binding to the plasma protein alpha2-M or IgG and thus preventing phagocytosis by bovine PMNs.

Animals↗
PubMed1996

Effectiveness of an abdominal obesity reduction programme in men: the GutBuster "waist loss' programme.

OBJECTIVE: To examine the long term (1-2 year), as well as immediate effectiveness of a "waist loss' programme for men. DESIGN: Two preliminary studies are reported; one following a small group of 42 men over two years after a 6 week "GutBuster' course, the second following men for 1 year after having completed the initial 6 week programme (n = 83), or the initial course plus an additional six fortnightly "advanced' course (n = 37). MEASUREMENTS: Waist, hip and weight measures were reported for the 2 year group; waist and hip only in study 2. Dietary fat, exercise and alcohol intake were also recorded in study 2 through the use of questionnaires. The goal for the initial course was a 1% waist loss per week. RESULTS: All groups achieved an average waist loss > 1%/week during the initial programme. Waist sizes reported in study 1 were significantly less after 2 years (t = 8.28, p < 0.001) averaging a 6% loss in the group. This equated with an average weight loss of 5.5 kg. A repeated measures ANOVA also showed a significant main effect (F = 85.35; p < 0.0001) for waist losses and an interaction effect (F = 16.53; p < 0.0001) between initial and advanced groups after 1 year in study 2. Average waist losses were 4% and 10% respectively. There were also significant changes in dietary fat intake, exercise and alcohol consumption. CONCLUSION: Reductions in waist size in men appear to be more feasible than weight losses in women. "Waist loss' may also be a more valid measure of fat loss in men that body mass measures.

Abdomen↗
PubMed1994

Dose intensive therapy with autologous blood stem cell transplantation in breast cancer.

BACKGROUND: Breast cancer is the commonest form of cancer in Australian women. Although approximately 50% of women with breast cancer achieve long term survival by current management methods, recurrent or metastatic disease is generally incurable. In addition, women with Stage II disease with > 10 positive axillary lymph nodes and also women with locally advanced disease (Stage III) have a poor survival even with adjuvant therapy. AIMS: To assess the toxicity and efficacy of high-dose chemotherapy with autologous peripheral blood stem cell (PBSC) transplantation in women with both metastatic and poor prognosis primary breast cancer. METHODS: Twenty-eight women with either metastatic (15) or poor prognosis (13) primary breast cancer were enrolled in the study between November 1988 to January 1993. PBSC were harvested using high-dose cyclophosphamide (Cy) with or without granulocyte-colony stimulating factor (G-CSF) and a myeloablative regimen of Cy, melphalan and carboplatin (CMCp) was used in the transplantation phase. RESULTS: Optimum numbers of stem cells were harvested in 85% of patients. The use of five G/m2 Cy plus G-CSF resulted in better PBSC yields and a significant reduction in haematologic morbidity when compared to mobilisation with Cy alone. Twenty-two women underwent 23 PBSC transplants (PBSCT). There have been two early deaths due to sepsis. The predominant morbidities observed following high dose chemotherapy and transplantation have been nausea, mucositis and diarrhoea. The median number of days to discharge following infusion of PBSC was 15 (range 11-21). At a median follow up time of 1.1 years (range 0 months-3.6 years), 8/22 (36%) evaluable patients remain alive and disease free while 14/22 (64%) have relapsed or progressed or died. CONCLUSION: High-dose chemotherapy and autologous PBSCT is a potentially highly effective treatment of women with metastatic and poor prognosis primary breast cancer. Randomised studies are required to compare this form of therapy to more standard forms of treatment in breast cancer.

Adult↗
PubMed1994

Invasion of rabbit ileal tissue by Enterobacter cloacae varies with the concentration of OmpX in the outer membrane.

The outer membrane protein OmpX of Enterobacter cloacae shows high amino acid homology with virulence proteins PagC and Rck from Salmonella typhimurium and with Ail from Yersinia enterocolitica. Here we demonstrate a role for OmpX in the invasion of rabbit ileal tissue by E. cloacae. An organ culture system was used for maintenance of rabbit gut tissue during the experiments. The invasiveness of three E. cloacae strains, which differed in OmpX content, were compared with each other and with that of Salmonella typhimurium TML (a highly invasive strain) and S. typhimurium LT7 (a noninvasive strain). There was no significant difference between the invasiveness of the wild type and that of an ompX deletion mutant strain of E. cloacae; they were equally as invasive or less invasive than S. typhimurium LT7. The invasiveness of an OmpX overproducer strain of E. cloacae was 10-fold higher than that of its immediate parent carrying only the multicopy plasmid, higher than that of S. typhimurium LT7, but lower than that of S. typhimurium TML. The invasiveness of E. cloacae thus varied directly with the level of OmpX in the outer membrane in rabbit ileal enterocytes challenged in situ.

Animals↗
PubMed1993

Placental protein 14 levels in uterine flushing and plasma of women with unexplained infertility.

OBJECTIVES: To measure concentrations of placental protein 14 (PP14) in uterine flushings and plasma samples obtained from patients with unexplained infertility and to compare the results of those of normal fertile women. DESIGN: Prospective study. SETTING: Infertility and gynaecology outpatient clinics at the Jessop Hospital for Women, Sheffield, United Kingdom. PATIENTS: Sixteen patients with unexplained infertility and 12 normal fertile women who had been previously sterilized. INTERVENTIONS: Daily monitoring of luteinizing hormone (LH) to detect the LH surge; uterine flushings and blood samples were obtained on days 7, 10, and 12 after the LH surge. MAIN OUTCOME MEASURES: The measurement of PP14 concentration in uterine flushings and plasma samples throughout the luteal phase. RESULTS: Levels of PP14 in uterine flushings of patients with unexplained infertility were significantly lower than those of normal fertile women on days LH +10 and LH +12. No significant differences were observed between the two groups in PP14 levels in uterine flushings on day LH +7 and plasma samples on days LH +7, LH +10, and LH +12. CONCLUSIONS: Patients with unexplained infertility have reduced concentrations of PP14 in uterine flushings but not in plasma samples as compared with normal fertile women. Placental protein 14 measurement in uterine flushings may be a more valuable method of assessing endometrial function in infertile patients than plasma levels of the protein.

Adult↗
PubMed1992

Factors affecting blood stem cell collections following high-dose cyclophosphamide mobilization in lymphoma, myeloma and solid tumors.

Sixty patients with malignancy were enrolled in a study of high-dose chemotherapy and peripheral blood stem cell transplantation (PBSCT). Stem cells were harvested prior to PBSCT using high-dose cyclophosphamide (CY) mobilization (4 or 7 g/m2) with collection of a median of 4.6 x 10(8)/kg mononuclear cells (range 0.2-9.5) and 21.6 x 10(4)/kg colony forming unit-granulocyte/macrophage (CFU-GM) (range 0.1-220). Forty-seven patients were mobilized once, 11 required two cycles and two required three cycles. Eight patients (13%) failed to reach the optimum CFU-GM target (greater than 15 x 10(4)/kg) following CY mobilization. A number of factors identified those patients who were likely to achieve optimum CFU-GM collections with CY mobilization. These included the use of the higher CY mobilization dose, a longer interval from last chemotherapy cycle to mobilization, and a higher premobilization bone marrow CFU-GM level. Patient's age, the degree of bone marrow infiltration, the nature of disease or the number of pre-mobilization chemotherapeutic cycles did not affect the ability to collect optimum CFU-GM numbers. Whilst the mobilization procedure was associated with moderate non-hematologic toxicity, significant hematological morbidity was observed primarily in patients mobilized using the 7 g/m2 dose. Refinements to the protocol, in particular the use of hematopoietic growth factors, are currently under investigation.

Adolescent↗
PubMed1991

A controlled study of psychoanalytic treatment of brittle diabetes.

The study compared two equivalent groups of 11 diabetic children with grossly abnormal blood glucose profiles necessitating repeated admissions to a hospital. Patients in the treatment group were offered an intensive inpatient treatment program including psychoanalytic psychotherapy three to four times a week, which took place on the hospital ward and lasted an average of 15 weeks. The intervention was highly effective in improving the diabetic control of the children, and this was maintained at a 1 year follow-up. Patients in the comparison group, who were offered only inpatient medical intervention, returned to their prehospitalization level of metabolic control within a period of 3 months from discharge.

Adolescent↗
PubMed1991

Fatal incidents involving pickup trucks in Alabama.

Death or injury resulting from crashes involving light trucks (ie, pickup trucks) is a significant problem. Data show that fatal crashes and occupant fatalities involving light trucks have steadily increased since 1983. This project describes vehicle crashes involving passengers riding in the beds of pickup trucks. Actual crashes were identified through the Fatal Accident Reporting System (FARS) of the National Highway Traffic Safety Administration. The 40 incidents studied involved 204 pickup truck passengers. Of these, 45 were killed, 107 sustained visible injuries or were carried from the scene, 6 had bruises and abrasions, and 2 had no visible injury but were briefly unconscious or had a documented complaint of pain. The risk of death among pickup truck passengers who were fully ejected from the vehicle was nearly six times that of passengers not fully ejected. Correspondingly, the risk of ejection from the truck was 26.7 times greater among occupants riding in the bed than occupants riding in the cab.

Accidents, Traffic↗
PubMed1989

Body mass as a determinant of seat belt use.

Prevention of death and injury from motor vehicle accidents depends in part on seat belt use. Understanding the determinants of seat belt use is important for developing strategies to increase seat belt use. The cross-sectional association between body mass index (BMI) and self-reported seat belt use was analyzed using data from 3,140 Health Risk Appraisals completed by Tennessee residents during 1986. Persons in the lowest quintile BMI (less than or equal to 21.8 kg/m2) stated they use seat belts 63% (SD = 38%) of the time compared to persons in the highest BMI quintile (greater than or equal to 29.0 kg/m2) who reported using seat belts 50% (SD = 38%) of the time. BMI remained associated with seat belt use after adjustment for age, sex, race, education, cigarette use, alcohol use, drug use, urban/rural residence, state area of residence, miles driven per year, self-reported physical activity, and satisfaction with life. For a 1 kg/m2 increase in BMI, seat belt use declined -0.73% (95% CI = -1.01, -0.46), and the relative odds of not being a frequent seat belt user increased 3% (odds ratio 1.03, 95% CI = 1.01, 1.05). BMI was the third variable selected in a step-wise multiple linear regression after education and race. The BMI/seat belt association, if causal, has implications for (1) targeting of education programs to likely nonusers by traffic safety agencies; (2) targeting health promotion messages to likely nonusers by primary care providers; and (3) design of automobile seats and restraint devices.

Body Weight↗
PubMed1989

Derivation and validation of a decision rule for predicting seat belt utilization.

Information from 3,108 health risk appraisals completed by Tennessee residents in 1986 was used to develop a decision rule for predicting seat belt utilization. The data set was randomly divided into derivation and validation sets. The dependent variable was self-reported seat belt use (percentage). Using multiple linear regression, the following rule was derived: score = [age (years) X 0.24] + [mood-affecting drug use X 4.09] + [miles driven per year X 5.08] + [education level X 11.18] - [race X 18.31] - [cigarette use X 2.73] - [satisfaction with life X 3.50] - [body mass (kg/m2) X 0.83] - [urban/rural residence X 4.08]. Likelihood ratios for persons stating 0 to 25 percent seat belt use were compared with those for persons stating 76 to 100 percent use. The prevalence of 0 to 25 percent seat belt use was 31 percent in the derivation set and 33 percent in the validation set. At the lowest quintile of score (-1 or less), the likelihood ratios were 4.18 and 3.31 in the derivation and validation sets, respectively. At the highest quintile of score (26 or more) the likelihood ratios were 0.29 and 0.38, respectively. At score levels less than 10 the decision rule had a sensitivity of 59 percent and 55 percent and a specificity of 80 percent and 81 percent in the derivation and validation sets, respectively. This decision rule may be used by primary care physicians to identify persons likely not to use seat belts and target them for health promotion efforts.

Choice Behavior↗
PubMed1980

Antiemetics for patients treated with antitumor chemotherapy.

The clinical efficacy of antiemetic drugs was tested in cancer patients who were given a placebo and two antiemetic drugs alone and in combination according to random sequences. The method of investigation allowed assessment of the antiemetic effect and side effects of each drug or combination of drugs using a minimum number of patients. The trial design takes into account carry-over effects and biased selection and is potentially useful in the study of drug side effects. Fifteen patients received cyclizine, metoclopramide, cyclizine and metoclopramide, or placebo in a random sequence without evidence that the drugs tested were better than the placebo. A combination of Nabilone and metoclopramide was used in an unrandomized pilot study (prior to the withdrawal of Nabilone from clinical use); these patients recorded better scores for nausea and vomiting and patient acceptability than those in the randomized study. Present antiemetics remain inadequate and although cannabinol derivatives show an improved antiemetic effect, they cause moderate side effects themselves.

Adolescent↗
PubMed1976

Concentration of oestrogens and androgens in human ovarian venous plasma and follicular fluid throughout the menstrual cycle.

The concentrations of androstenedione, testosterone, oestrone and oestradiol-17beta were measured in peripheral and ovarian venous blood and follicular fluid of women at various stages of the menstrual cycle. The concentration of oestradiol was similar in small follicles (diameter less than 8 mm) at all stages of the menstrual cycle and in large follicles (diameter greater than or equal to 8 mm) except during the mid- and late follicular phase when the concentration reached a peak (approximately 1500 ng/ml). The concentration of androstenedione was lowest in large preovulatory follicles at midcycle at a time when the secretion into the ovarian vein was markedly increased. The concentration of testosterone in large follicles (greater than or equal to 8 mm) was unchanged during the follicular phase whereas in small follicles there was a peak at mid-cycle. The rise in the concentration of testosterone and androstenedione at mid-cycle in peripheral plasma may be due to increased secretion by the preovulatory follicle into the ovarian vein. It is suggested that the relatively low concentration of androstenedione in follicular fluid of the preovulatory follicle arises from increased aromatization by granulosa cells in the course of oestrogen synthesis.

Adult↗