Negative cutaneous effects of medicinal plants in Senegal.

Use of medicinal plants is common and widespread throughout Africa, including in Senegal. Because efficacy has been demonstrated, public policies have been instituted that have allowed plant-based therapies to have an important role in general primary care. However, little is known about the cutaneous safety of many plant-based therapies. In this 6-month prospective study all cases of dermatitis induced or aggravated by exclusive use of medicinal plants were evaluated via skin allergy testing. The results were classified and compared with the available literature. Forty-three cases of plant-therapy-associated cutaneous reactions were identified, including worsening of existing conditions (56%), recurrence of a previously resolved condition (16%) and new dermatitis arising spontaneously (28%). In the cases where the condition was new, generalized exfoliative dermatitis occurred in 42% of cases with an average time of onset of 9 days. Specific plants were identified in 65% of cases and included 18 varieties. The frequency and severity of plant-induced cutaneous reactions should be the basis for the creation of a phytovigilance programme and re-evaluation of how traditional medicine is used in the general population. When irritation occurs, identification of the responsible plant and allergy testing should be the first steps towards relieving symptoms.

Direct sequencing and RipSeq interpretation as a tool for identification of polymicrobial infections.

In this study, RipSeq Mixed, a software resolving uninterpretable mixed DNA sequencing chromatograms, revealed the bacterial content of 15 polymicrobial samples. Direct sequencing combined with RipSeq Mixed constitutes a valuable supplement to cultivation, particularly when cultivation is negative and direct sequencing is inconclusive despite continued clinical indications of infection.

Detection of microbial diversity in endocarditis using cultivation-independent molecular techniques.

BACKGROUND: The aim of this study was to investigate whether the diagnosis of infective endocarditis (IE) could be improved using molecular tools in addition to standard microscopy and cultivation methods. METHODS: Cultivation was performed on blood or tissue samples as recommended in the modified Duke criteria. The molecular tools included a broad-range polymerase chain reaction (PCR)-based denaturant gradient gel electrophoresis and a more detailed identification by constructing clone libraries followed by sequencing. RESULTS: Of 14 patients, 12 were positive by blood or tissue cultivation and all were monomicrobial. Molecular methods showed the presence of DNA from multiple bacterial species in 6 of the samples and indicated a larger variety of bacteria in the different samples than identified by cultivation. For 8 of the patients there was a good correlation between the results of cultivation and molecular methods, and for these samples the identified bacteria are known to be frequently involved with IE. Many of the additional bacteria only identified by the molecular methods are not reported as common causes of IE. CONCLUSIONS: Application of molecular tools in addition to cultivation indicated that polymicrobial infections might be of importance in IE. However, the significance of the more unknown microorganisms needs to be investigated further.

Aggregation and fibrillation of bovine serum albumin.

The all-alpha helix multi-domain protein bovine serum albumin (BSA) aggregates at elevated temperatures. Here we show that these thermal aggregates have amyloid properties. They bind the fibril-specific dyes Thioflavin T and Congo Red, show elongated although somewhat worm-like morphology and characteristic amyloid X-ray fiber diffraction peaks. Fibrillation occurs over minutes to hours without a lag phase, is independent of seeding and shows only moderate concentration dependence, suggesting intramolecular aggregation nuclei. Nevertheless, multi-exponential increases in dye-binding signal and changes in morphology suggest the existence of different aggregate species. Although beta-sheet content increases from 0 to ca. 40% upon aggregation, the aggregates retain significant amounts of alpha-helix structure, and lack a protease-resistant core. Thus BSA is able to form well-ordered beta-sheet rich aggregates which nevertheless do not possess the same structural rigidity as classical fibrils. The aggregates do not permeabilize synthetic membranes and are not cytotoxic. The ease with which a multidomain all-alpha helix protein can form higher-order beta-sheet structure, while retaining significant amounts of alpha-helix, highlights the universality of the fibrillation mechanism. However, the presence of non-beta-sheet structure may influence the final fibrillar structure and could be a key component in aggregated BSA's lack of cytotoxicity.