Trichomonas vaginalis is the etiological agent of trichomoniasis, the most prevalent non-viral sexually transmitted disease worldwide. Trichomoniasis is a widespread, global health concern, and occurring at an increasing rate. Infections of the female genital tract can cause a range of symptoms, including vaginitis and cervicitis, whilst infections in males are generally asymptomatic. The relatively mild symptoms, and lack of evidence for any serious sequelae, have historically led to this disease being under diagnosed, and under researched. However, growing evidence that T. vaginalis infection is associated with disease states with high morbidity in both men and women has increased the efforts to diagnose and treat patients harbouring this parasite. The pathology of trichomoniasis results from damage to the host epithelia, caused by a variety of processes during infection, and recent work has highlighted the complex interactions between the parasite and host, commensal microbiome, and accompanying symbionts. The commercial release of a number of nucleic acid amplification tests (NAATs) has added to the available diagnostic options. Immunoassay based Point of Care testing is currently available, and a recent initial evaluation of a NAAT Point of Care system has given promising results, which would enable testing and treatment in a single visit.

bA loop-mediated isothermal amplification (LAMP) assay for open reading frame 1 (ORF1) of the glutamine synthetase gene of Neisseria gonorrhoeae was able to tolerate urea concentrations of <1.8 M, compared with a PCR assay that was functional at concentrations of <100 mM. The LAMP assay was as sensitive as the PCR assay while being faster and simpler to perform.

The screening of recently patented derivatives of the standard phenothiazinium agents methylene blue and toluidine blue was carried out against Propionibacterium acnes, the main bacterium associated with acne vulgaris. Comparative tests were made using the topical agent benzoyl peroxide (BPO) and standard tetracyclines. Each of the photosensitizers employed, including the lead compounds, was photobactericidal at lower concentrations than BPO, and produced a much more rapid kill than the tetracyclines. In addition, the tetracyclic and pentacyclic phenothiazinium derivatives exhibited high light:dark kill ratios, suggesting that these examples might be particularly useful in practice.

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Infective endocarditis (IE) is an evolving disease resulting in high morbidity and mortality. Despite medical and diagnostic advances, the incidence of the disease has remained unchanged, reflecting the changing epidemiological and microbiological profile of IE. Classical risk factors such as rheumatic heart disease have now been overtaken by new risk factors including an ageing population, degenerative valve disease and intravenous drug use. The routine use of invasive procedures, implantable cardiac devices and prosthetic heart valves has served to increase the number of at-risk patients. The microbiology of IE mirrors the changing risk factors, with staphylococcal infections predominating over viridans streptococci. An overview of this rare disease is given describing current understanding, investigation and changing epidemiology and microbiology of IE.

A loop mediated isothermal amplification (LAMP) assay for ORF1 of Neisseria gonorrhoeae was able to tolerate urea concentrations of 1.8M and below, compared with a PCR assay which was functional at concentrations of <100mM. The LAMP assay was as sensitive as the PCR assay, whilst faster and simpler to perform.Gonorrhoea is the second most common sexually transmitted infection in the developed world (1) with 106 million incidences of gonorrhoea infection reported yearly worldwide (2), representing a significant global health burden.Nucleic acid amplification testing (NAAT) for gonorrhoea is becoming more widespread. NAATs offer unparalleled specificities and sensitivities, with PCR assays typically boasting sensitivities and specificities of >95% and 100% respectively, compared with sensitivities of ~68% obtained via cultureLAMP is a novel nucleic acid amplification method, designed to amplify target nucleic acid in a highly specific and rapid manner, under isothermal conditions (4). The LAMP reaction requires a constant temperature of ~63 o C, and can be easily carried out in a water bath (5). LAMP assays enable a more rapid diagnosis than PCR based tests, offer improved sensitivities (6,7), and have a higher tolerance for inhibitors present in a number of clinical samples, including faeces and blood (8).Diagnosis of genital Neisseria gonorrhoeae infection by NAAT is carried out from a variety of sample types, including invasive swab samples and urine specimens. Urea, present in urine, is a known inhibitor of PCR at concentrations over 50mM (9). Urea prevents the non-covalent bonding of the polymerase enzyme, and also interferes with primer annealing, hence inhibiting amplification (10).Diagnostically this leads to an increase in the likelihood of false-negative results and a reduction in assay sensitivity (11). Although the concentration of urea in adult human urine is highly variable, a previous study (9) found the average concentration of urea to be ~300mM, above the minimum concentration needed for PCR inhibition. The most simple methods for nucleic acid extraction, such the preparation of a crude lysate, chelex based methods, or proteinase K digestion, are unsuitable for processing urine samples for PCR, due to their inability to remove the inhibitory urea, and the use of more complex extraction methods is recommended (12).In the present study, the minimum concentration of urea inhibitory to LAMP was determined, in order to test the suitability of the LAMP assay for testing urine samples with simple extraction methods. The detection of N.gonorrhoeae DNA from spiked urine samples was used to test this principle.N.gonorrhoeae (ATCC 19424) was cultured on chocolate agar (blood agar base, Sigma Aldrich, UK; defibrinated horse blood, TCS, UK) at 37 o C with 5% CO2.LAMP primers were designed for ORF1 of the glutamine synthetase (glnA) gene (Genbank accession number M84113) of N. gonorrhoeae. This region offers excellent diagnostic sensitivity as a PCR target for this organism (13). LAMP primers were desig...

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The presence of V kappa IIIb light chains in the sera of rheumatoid arthritis (RA) patients has been evaluated by an enzyme-linked immunosorbent assay (ELISA). V kappa IIIb light chains have been confirmed to be largely restricted to IgM, and were rarely detected in the IgG fraction of sera. The concentration of total serum V kappa IIIb did not significantly vary with age, nor did it correlate with IgM-rheumatoid factor (RF) titre. Although total serum V kappa IIIb was not significantly increased in RA patients compared with matched controls, IgM-RFs frequently contained V kappa IIIb. Using flow cytometry, CD5-positive B-cells were not increased in these RA patients compared with healthy laboratory control personnel. Furthermore, there was no direct correlation between total serum IgM V kappa IIIb content and CD5-positive B-cell numbers in peripheral blood.