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Background Severe vitamin C deficiency, or scurvy, encompasses a syndrome of multisystem abnormalities due to defective collagen synthesis and antioxidative functions. Among the more common presentations is a combination of oral or subcutaneous hemorrhage with lower extremity pain, the latter often exhibiting inflammatory bone changes on magnetic resonance imaging (MRI). Case presentation A 12-year-old male with anorexia nervosa presented with asymmetric painful swelling of multiple fingers of both hands. Imaging demonstrated soft tissue and bone marrow edema of several phalanges, without arthritis, concerning for an inflammatory process. Extensive imaging and laboratory evaluations were largely unrevealing, with the exception of a severely low vitamin C level and a moderately low vitamin D level. A diagnosis of scurvy was made and supplementation was initiated. Within 3 weeks of treatment, serum levels of both vitamins normalized and the digital abnormalities resolved on physical exam. Conclusions This represents the first description of scurvy manifesting with bone and soft tissue changes limited to the hands. There must be a high index of suspicion for scurvy in children with restricted dietary intake or malabsorption who have bone pain, irrespective of location of the lesions.

The microtubule-severing protein Katanin is now shown to possess microtubule depolymerising activity. Purified recombinant Katanin exerts both activities in vitro. In migrating cells from Drosophila, Katanin localizes at the leading edge where it negatively regulates cell motility. Regulation of microtubule dynamics at the cell cortex is important for cell motility, morphogenesis and division. Here we show that the Drosophila katanin Dm-Kat60 functions to generate a dynamic cortical-microtubule interface in interphase cells. Dm-Kat60 concentrates at the cell cortex of S2 Drosophila cells during interphase, where it suppresses the polymerization of microtubule plus-ends, thereby preventing the formation of aberrantly dense cortical arrays. Dm-Kat60 also localizes at the leading edge of migratory D17 Drosophila cells and negatively regulates multiple parameters of their motility. Finally, in vitro, Dm-Kat60 severs and depolymerizes microtubules from their ends. On the basis of these data, we propose that Dm-Kat60 removes tubulin from microtubule lattice or microtubule ends that contact specific cortical sites to prevent stable and/or lateral attachments. The asymmetric distribution of such an activity could help generate regional variations in microtubule behaviours involved in cell migration.

There is much interest in the positive health effects of nutraceuticals, in particular, polyphenols, which have both antioxidant and prooxidant characteristics. Pyruvate, a scavenger of hydrogen peroxide, is a component in some, but not in all, commercial formulations of cell culture media, Dulbecco’s modified Eagle’s medium in particular. This study showed that the cytotoxicities to human fibroblasts of hydrogen peroxide, tert-butyl hydroperoxide, and various prooxidant nutraceuticals were lessened in Dulbecco’s modified Eagle’s medium formulated with pyruvate, as compared to the same medium but formulated without pyruvate. Intracellular glutathione was unaffected in cells treated with hydrogen peroxide in Dulbecco’s modified Eagle’s medium formulated with pyruvate, as compared to medium formulated without pyruvate. In these studies, intracellular glutathione was analyzed in acid-soluble cell extracts by determining the oxidation of reduced glutathione by 5,5′-dithiobis(2-nitrobenzoic acid) to glutathione disulfide, with the formation of the yellow chromagen, 5-thio-2-nitrobenzoic acid, measured spectrophotometrically at 412 nm and by the visualization of reduced glutathione in cells stained with the fluorescent dye, Cell Tracker™ Green 5-chloromethylfluorescein diacetate. A survey of various cell culture media, formulated with and without pyruvate, confirmed that the level of added hydrogen peroxide was greatly lessened in those media formulated with pyruvate. This study suggested that the pyruvate status of Dulbecco’s modified Eagle’s medium be specified in the experimental design, especially in studies involving oxidative stress.