Biomedical subjects

Susan Macmillan

Publications and source records attributed to Susan Macmillan.

4 recordsLinked to original sources

PubMed2006

Practical three color live cell imaging by widefield microscopy.

Live cell fluorescence microscopy using fluorescent protein tags derived from jellyfish and coral species has been a successful tool to image proteins and dynamics in many species. Multi-colored aequorea fluorescent protein (AFP) derivatives allow investigators to observe multiple proteins simultaneously, but overlapping spectral properties sometimes require the use of sophisticated and expensive microscopes. Here, we show that the aequorea coerulescens fluorescent protein derivative, PS-CFP2 has excellent practical properties as a blue fluorophore that are distinct from green or red fluorescent proteins and can be imaged with standard filter sets on a widefield microscope. We also find that by widefield illumination in live cells, that PS-CFP2 is very photostable. When fused to proteins that form concentrated puncta in either the cytoplasm or nucleus, PSCFP2 fusions do not artifactually interact with other AFP fusion proteins, even at very high levels of over-expression. PSCFP2 is therefore a good blue fluorophore for distinct three color imaging along with eGFP and mRFP using a relatively simple and inexpensive microscope.

Journal Article↗

PubMed2004

An evaluation of economics and acceptability of screening for Chlamydia trachomatis infection, in women attending antenatal, abortion, colposcopy and family planning clinics in Scotland, UK.

OBJECTIVE: The aims of this study were to determine cost effectiveness of screening for Chlamydia trachomatis in hospital-based antenatal and gynaecology clinics, and community-based family planning clinics. Additionally, women's views of screening were determined in the hospital-based clinics. DESIGN: Cost effectiveness based on decision model. Model probabilities were generated for a hypothetical sample of 250 women in each age group in each setting, based on prevalence studies, published data and expert opinion. A prospective observational study was used to generate data on prevalence and acceptability. SETTING: Antenatal, gynaecology and family planning clinics in Aberdeen, Edinburgh and Glasgow. SAMPLE: Prevalence was estimated in 2817 women. Acceptability was determined in 484 women. METHODS: An economic evaluation was performed using prevalence data from this and a previous study, and using outcome data from the literature and observational work. Incremental cost effectiveness ratios were estimated for each age group and clinical setting. Sensitivity analyses were performed to determine the robustness of incremental cost effectiveness ratios to changes in the incidence of long term sequelae and costs. The prevalence of infection was determined by nucleic acid amplification of urine samples or endocervical swabs. Knowledge of C. trachomatis and women's views of screening were determined using structured questionnaires. MAIN OUTCOME MEASURES: Direct health service costs of screening, incidence and costs associated with adverse sequelae, women's views of screening and prevalence of infection. RESULTS: The estimated cost of screening 250 women in each age group in each the four sample populations (total population of 3750) is 49,367 UK pounds, while preventing 64 major sequelae. This represents a net cost of 771.36 UK pounds in preventing one major sequela. Selective screening of all women under 20 years and all patients attending abortion clinics were shown to be the most cost effective strategies. These results were relatively insensitive to changes in estimated parameters, such as uptake rate, probabilities and unit costs of all major sequelae averted. Prevalence (95% CI) of infection in the highest risk groups (those aged under 20 in both antenatal and abortion clinics) was 12.1% (8.6-16.7) and 12.7% (7.3-21.2), respectively. The majority (>95%) of women agreed with a policy of regular screening for C. trachomatis, and screening in the settings employed in this study was largely acceptable. CONCLUSIONS: A single episode of screening for C. trachomatis does not result in net cost savings. Currently recommended strategies of screening for C. trachomatis in women under 25 years of age in abortion clinics are supported by our data on prevalence and acceptability. These data also suggest that hospital-based screening strategies should be further extended to include younger women attending antenatal clinics and all women of reproductive age attending colposcopy clinics.

Ambulatory Care↗

PubMed2003

Parallel observation of four methods for screening women under 25 years of age for genital infection with Chlamydia trachomatis.

OBJECTIVES: To compare four methods of screening women for Chlamydia trachomatis in an obstetrics and gynaecology department. STUDY DESIGN: A total of 303 healthy women under 25 years were recruited from antenatal, induced abortion, and family planning clinics. Each underwent parallel testing of endocervical specimens by enzyme immunoassay (EIA) and ligase chain reaction (LCR), vulval swabs by LCR, and urine by LCR. Outcome measures included sensitivity, specificity, acceptability of each method, and the influence of pregnancy. RESULTS: Overall prevalence (95% CI) was 9.9% (6.8-14%). All methods had a high rate of detection (75-100%), not affected by pregnancy. Urine was most acceptable, followed by vulval swabbing. CONCLUSIONS: Opportunistic screening of women under 25 years attending obstetric and gynaecology affiliated clinics found high rates of C. trachomatis infection. Both urine and vulval swab methods were highly sensitive, acceptable, and not affected by pregnancy status. Due to pragmatic issues surrounding the urine method, screening by vulval swabs deserves wider recognition.

Adolescent↗

PubMed2002

Chlamydia trachomatis in subfertile women undergoing uterine instrumentation. The clinician's role.

Most women attending a fertility clinic will undergo uterine instrumentation either diagnostically and/or therapeutically. This places them at potential risk of chlamydial pelvic inflammatory disease. Clinicians remain unclear about the roles of screening, serology and prophylactic antibiotics. A review of the evidence suggests that women <25 years and those older with risk factors, men with risk factors and gamete donors should have their lower genital tract screened for Chlamydia trachomatis by a sensitive test. More information is required before screening men by age can be recommended. Serology in its present form cannot be advocated as a screening tool. Those women with a past history of chlamydial morbidity or a diagnosis of tubal pathology should, in addition to screening, be covered with prophylactic antibiotics when undergoing uterine instrumentation. The partner should be screened for sexually transmitted infections. Non-selective use of prophylactic antibiotics serves only to increase the problem of antibiotic resistance and maintain the bacterial load of chlamydia in the community.

Adult↗