Introduction: Understanding the complex chemical signalling of plants and insects is an important component of chemical ecology. Accordingly, the collection and analysis of chemical cues from plants in their natural environment is integral to elucidation of plant-insect communications. Remote plant locations and the need for a large number of replicates make in situ headspace analyses a daunting logistical challenge.
View Article and Find Full Text PDFAn automated sample preparation system was developed and tested for the rapid detection of Bacillus anthracis endospores by gas chromatography-mass spectrometry (GC-MS) for eventual use in the field. This reactor is capable of automatically processing suspected bio-threat agents to release and derivatize unique chemical biomarkers by thermochemolysis (TCM). The system automatically controls the movement of sample vials from one position to another, crimping of septum caps onto the vials, precise delivery of reagents, and TCM reaction times and temperatures.
View Article and Find Full Text PDFHuman leukocyte antigen class II typing, using polymerase chain reaction-sequence-specific primers, was performed in 52 Black South Africans with systemic sclerosis (SSc) and 112 controls. Increased frequencies of DR2 in the overall SSc group (OR = 2.4), DRB1*0301 in the limited cutaneous SSc (lcSSc) subset (OR = 9.
View Article and Find Full Text PDFRheumatology (Oxford)
December 2000
Objectives: To investigate whether six microsatellite markers known to map closely to genes involved in fibrosis are associated with systemic sclerosis (SSc).
Methods: Markers mapping to TGFbeta1, TGFbeta2, TGFbeta3, PDGFB, TIMP1 and COL5A2 were genotyped and allele frequency distributions compared in 191 patients and 196 controls. As TIMP1 maps to the X chromosome, male and females were analysed separately.
Topoisomerase I (topo I) is a major autoantigen recognized by autoantibodies in about 30% of sera from patients with systemic sclerosis (SSc). Certain HLA-DRB1 and HLA-DQB1 alleles have been reported to be associated with autoantibody and T-cell responses to topo I suggesting a T-cell dependent process. We have examined the MHC class II allele associations with anti-topo I antibodies in 16 patients with SSc compared to 250 healthy controls.
View Article and Find Full Text PDFWe report 14 patients with minocycline-induced lupus-like syndrome (four men, 10 women; mean age 27.8 years) who developed a lupus-like illness after chronic use of minocycline for acne (1-10 years, median 3.8).
View Article and Find Full Text PDFThere are three classes of RNA polymerase enzyme (RNAPs I, II and III). In systemic sclerosis (SSc), three main groups of anti-RNAP sera have been characterized by radioimmunoprecipitation techniques: anti-RNAP I/III sera, anti-RNAP I/II/III sera, and a group precipitating both RNAP II and topoisomerase I (topo I). Some sera in this third group precipitate the phosphorylated (IIO) form of RNAP II in the absence of the unphosphorylated (IIA) form.
View Article and Find Full Text PDFThe potential of specific human semen markers, P30 and 19-OH prostaglandin F1 alpha/F2 alpha (PG F), ELISAs were compared in a blind trial. The PG F assay was shown to be at least ten times more sensitive than the P30 technique although cross reactivity problems with spermicidal creams and other possible domestic contaminants were identified. A simple method for the removal of such contaminants using a phenyl boronate column (PBA) was evaluated in an extensive blind trial.
View Article and Find Full Text PDFThe prevalence of autoantibodies to the three RNA polymerase (RNAP) enzymes in the sera of 249 SSc patients was measured using the technique of immunoprecipitation of 35S-methionine-labelled K562 cell extracts. Forty-six anti-RNAP sera were detected (18.5%) and three main groups were identified: anti-RNAP I/III sera (10; 4.
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