Biomedical subjects

P A Bolton

Publications and source records attributed to P A Bolton.

4 recordsLinked to original sources

PubMed2001

High-frequency ultrasound imaging of the skin during normal and hypertensive pregnancies.

BACKGROUND/AIMS: Diagnosis of preeclampsia is currently made from blood pressure measurements taken at antenatal visits (either at the hospital or in the community). The aim of this work was to see whether the presence of underlying hypertensive diseases is accompanied by changes in the skin of pregnant women, which can be visualized using high-frequency diagnostic ultrasound. METHODS: This was a prospective study of pregnant and non-pregnant, hypertensive and non-hypertensive patients visiting the outpatient department of a central London Teaching Hospital. The study group consisted of 93 women, of which 30 were non-hypertensive in the second trimester of pregnancy, 26 were non-hypertensive in the third trimester of pregnancy, 9 were hypertensive in the second trimester of pregnancy, and 14 were hypertensive in the third trimester of pregnancy. Fourteen non-pregnant women of comparable age were recruited as controls. Changes in abdominal skin thickness and also skin structure, as analysed by fractal image analysis, was assessed in each patient. RESULTS: In a normal pregnancy, abdominal skin gets thinner as pregnancy progresses. In hypertensive patients, the skin thickness did not appear to alter. Image analysis of abdominal skin scans showed that the skin of non-hypertensive pregnant women and non-pregnant women are different. Whereas the analysis of hypertensive pregnant women and non-pregnant women showed they were the same. CONCLUSIONS: The data used to compare the groups indicates that if the abdominal skin of the patient does not get thinner as the pregnancy progresses there is an indication that the patient may be hypertensive. The fractal data comparing the groups indicates the following when comparing a patient's fractal signature with the non-pregnant control data: If the abdominal fractal for a pregnant woman is similar to the control group, there is an indication that the patient is hypertensive. It is difficult to predict hypertension in patients, and it is possible that a patient could develop severe preeclampsia between visits to the antenatal clinics. Therefore, if the high-frequency ultrasound scanner can pick up potential hypertensives early in pregnancy, these women could be identified as potentially high risk.

Adult↗

PubMed2001

The use of high-frequency diagnostic ultrasound to investigate the effect of hormone replacement therapy on skin thickness.

BACKGROUND/AIMS: Previous investigations have suggested that hormone replacement therapy (HRT) could have a positive effect on the maintenance of skin thickness post-menopause. Previous skin measurement devices have proved variable in their accuracy and ease of use. This investigation assessed the effect of HRT on the skin in a noninvasive way, using high-frequency diagnostic ultrasound. METHOD: The study was a cross-sectional observational study, carried out at a menopause and gynaecology outpatient's clinic. A total of 84 women (comprising 34 HRT users, 25 post-menopausal controls, and 25 premenopausal controls) took part in the study. Each volunteer was scanned using diagnostic ultrasound on the arm. Skin thickness measurements were made from each scan using computerised image analysis. RESULTS: Skin thickness was shown to be greater in the HRT group than in the post-menopausal controls (P<0.01). CONCLUSIONS: High-frequency diagnostic ultrasound proved to be a useful clinical tool and showed that HRT appears to help maintain skin thickness in menopause.

Cross-Sectional Studies↗

PubMed1995

Age, gender, and other predictors of the wasting syndrome among HIV-1-infected injecting drug users.

We conducted a study to identify predictors of the wasting syndrome among human immunodeficiency virus 1 (HIV-1)-seropositive injecting drug users. We enrolled 113 cases (defined as an unexplained loss of > 10% baseline weight) and 226 controls (defined as < 5% weight loss or any weight gain) from a HIV-1-seropositive cohort of injecting drug users (N = 630) into a nested case-control study. Crude predictors of wasting included: older age [odds ratio (OR) for a 1-year difference = 1.06], female gender (OR = 1.66), more years spent injecting drugs (OR for 1-year difference = 1.05), presence of diarrhea (OR = 3.78), lower percentage of CD4 T-lymphocytes (OR for 10-unit difference = 0.73), and higher log beta 2-microglobulin concentration (OR for 1 log difference = 11.3). After adjusting for CD4 cell level, beta 2-microglobulin concentration, diarrhea, gender, length and frequency of drug use, age, the presence of thrush, and education, independent predictors of weight loss in HIV-seropositive injecting drug users were female gender (OR = 2.23) and increasing age (OR for 1-year difference = 1.06). Frequency and duration of drug use were not strongly associated with the odds of developing wasting syndrome in this HIV-1-seropositive cohort. These data indicate that HIV wasting syndrome in injecting drug users is distinct from complications of drug use.

Adult↗

PubMedDate not supplied

Communicating across cultures: improving translation to improve complex emergency program effectiveness.

Translation is a vital activity in Complex Emergencies (CEs) in which the responders and the affected populations do not share the same language or culture. This particularly applies to CEs in developing countries in which a lack of local resources usually results in the importation of foreign aid workers. This paper describes many of the common issues surrounding translation that can affect CE response effectiveness, issues that frequently are not appreciated by aid workers, including clinicians. The authors describe how these issues can arise, their effects, and outline approaches to addressing them.

Disasters↗