Microneedle-based device for the one-step painless collection of capillary blood samples.

The advancement of point-of-care diagnostics and the decentralization of healthcare have created a need for the simple, safe, standardized and painless collection of blood specimens. Here, we describe the design and implementation of a capillary blood-collection device that is more convenient and less painful than a fingerstick and venepuncture, and collects 100 µl of blood. The technology integrates into a compact, self-contained device an array of solid microneedles, a high-velocity insertion mechanism, stored vacuum, and a microfluidic system containing lithium heparin anticoagulant. The use of the device requires minimal training, as blood collection is initiated by the single push of a button. In a clinical study involving 144 participants, haemoglobin A1c measurements from device-collected samples and from venous blood samples were equivalent, and the pain associated with the device was significantly less than that associated with venepuncture. The device, which has received premarket clearance by the US Food and Drug Administration, should help improve access to healthcare, and support healthcare decentralization.

Biotransformation of explosives by the old yellow enzyme family of flavoproteins.

Several independent studies of bacterial degradation of nitrate ester explosives have demonstrated the involvement of flavin-dependent oxidoreductases related to the old yellow enzyme (OYE) of yeast. Some of these enzymes also transform the nitroaromatic explosive 2,4,6-trinitrotoluene (TNT). In this work, catalytic capabilities of five members of the OYE family were compared, with a view to correlating structure and function. The activity profiles of the five enzymes differed substantially; no one compound proved to be a good substrate for all five enzymes. TNT is reduced, albeit slowly, by all five enzymes. The nature of the transformation products differed, with three of the five enzymes yielding products indicative of reduction of the aromatic ring. Our findings suggest two distinct pathways of TNT transformation, with the initial reduction of TNT being the key point of difference between the enzymes. Characterization of an active site mutant of one of the enzymes suggests a structural basis for this difference.

Ringworm causing childhood preseptal cellulitis.

A 4-year-old girl had redness and swelling of the left upper eyelid of 1 week's duration. She had been treated with topical fusidic add and oral flucloxacillin without resolution. Ophthalmic examination showed a diffuse, erythematous, tender lesion affecting the entire upper eyelid. There was a central area of skin ulceration with marked bleeding and discharge. Also found were small vesicles under the left eyebrow. The child's mother had noticed a scaly rash on her own forearm. Examination under anesthesia was carried out to assess the globe and to obtain samples for microbiology investigation. Microbiology scrapings showed fungal hyphae of the Dermatophyte group. Treatment with Griseofulvin was commenced, and complete resolution of the lesion occurred. To our knowledge there is only one similar case reported in the literature describing ring-worm as a cause of preseptal cellulitis. This case highlights the importance of considering alternative diagnoses when standard antibiotic treatment has failed.