Mark A. Pickett

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A 7.5 kbp cryptic plasmid is found in almost all isolates of Chlamydia trachomatis. Real-time PCR assays, using TaqMan chemistry, were set up to quantify accurately both the chlamydial plasmid and the single copy, chromosomal omcB gene in the infectious, elementary bodies (EBs) of C. trachomatis L1 440. Plasmid copy number was also determined in the EBs of(More)
Chlamydia trachomatis L2 was used to infect BGMK cells at an m.o.i. of 1.0, and the developmental cycle was followed by transmission electron microscopy and quantitative PCR (QPCR) for both chromosomal and plasmid DNA. Samples were taken at sequential 6 h time points. Subsequent analysis by QPCR showed that there was an initial slow replication period (0-18(More)
Human rhinoviruses (HRVs) cause the common cold and often induce lower airway symptoms such as cough and wheezing. Although HRV infection is presumed to involve primarily ciliated epithelial cells, this has not been confirmed in vivo, and the cellular distribution and spread of infection as well as the pathogenesis of cold related nasal and chest symptoms(More)
Variants of Chlamydia trachomatis in two Gambian villages with hyperendemic trachoma were analyzed by omp1-based polymerase chain reaction and sequencing from conjunctival swabs. Samples collected over a 22-month period included a complete cross-sectional study of each village. Overall, 4 genovar A and 4 B variants were characterized by point mutations in(More)
Direct amplification of the major outer membrane protein (MOMP) gene by polymerase chain reaction (PCR) was used to identify Chlamydia trachomatis in eye swabs from clinically active cases of endemic trachoma in a Gambian village. Chlamydial DNA was detected in 51% of 96 subjects with clinically active disease and in 5% of 37 clinically negative(More)
Reverse transcription and the polymerase chain reaction (PCR) were used to detect vascular endothelial growth factor (VEGF) mRNA in human placental tissue and cultured placental fibroblasts obtained during the first trimester of pregnancy. The primers for VEGF corresponded to areas in exon 4 and exon 8 of the VEGF gene. After one round of PCR three(More)
Basic fibroblast growth factor (bFGF) is a potent angiogenic factor that has also been implicated in granulosa cell and oocyte maturation. We now report the expression of messenger ribonucleic acid (mRNA) encoding bFGF in human granulosa and cumulus cells obtained at oocyte recovery in in vitro fertilisation patients. It was necessary to use the sensitive(More)
A novel method for the detection and typing of human papillomavirus (HPV) was developed using molecular beacon primers. The method is based on the use of HPV-specific primers containing a hairpin loop structure in which fluorescent donor and quencher groups are held in close proximity such that fluorescence is quenched. Amplification of the target sequence(More)
The application of a diagnostic and genotyping technique based on the polymerase chain reaction (PCR) to the study of trachoma epidemiology in the Gambian village of Jali is reported. PCR based on the major outer membrane protein (MOMP) gene of Chlamydia trachomatis appears to be more sensitive than either isolation or antigen detection by enzyme(More)
The major outer membrane protein (MOMP) of Chlamydia trachomatis is the main candidate antigen for a synthetic vaccine against chlamydial infection. Antibodies to surface-exposed epitopes on MOMP neutralize chlamydial infectivity but little is known about T-cell recognition of the molecule. We have measured primary human T-cell responses to recombinant(More)