A case of severe movement disorder with GNAO1 mutation responsive to topiramate.

We report the case of a 19-year-old female patient who had progressive chorea associated with a GNAO1 mutation. Chorea was refractory to multiple anticonvulsants, and the patient suffered from tiapride-induced neuroleptic malignant syndrome. After identification of a GNAO1 missense mutation at the age of 18years, topiramate treatment was initiated and the frequency of chorea decreased dramatically. The efficacy of topiramate may have been related to the inhibitory modulation of voltage-activated Ca2+ channels. Given the side effects and complications associated with neuroleptics and deep brain stimulation, respectively, topiramate is recommended for the first-line management of severe chorea associated with a GNAO1 mutation.

Mesalazine allergy in a boy with ulcerative colitis: clinical usefulness of mucosal biopsy criteria.

5-Aminosalicylic acid preparations have been used as first-line drugs for treatment of ulcerative colitis (UC). However, some patients with UC present with exacerbation of symptoms because of allergy to mesalazine. Diagnosis of mesalazine allergy in active UC may be challenging because its symptoms mimic those of UC. Here we describe a 13-year-old boy with mesalazine allergy who achieved remission when his medication was changed from mesalazine to salazosulfapyridine. During his clinical course mesalazine was prescribed twice, and on each occasion exacerbation of the symptoms occurred. We considered a diagnosis of mesalazine allergy, and this was confirmed by a drug lymphocyte stimulation test; the result for salazosulfapyridine was negative. On the basis of criteria involving simple mucosal biopsy combined with endoscopy for predicting patients with UC who would ultimately require surgery, we considered that the UC in this case might be susceptible to steroid treatment, and we therefore treated the patient with salazosulfapyridine and prednisolone. Shortly afterwards, remission was achieved and the patient has remained in good condition on salazosulfapyridine alone. When treating patients with mesalazine, the possibility of allergy should always be borne in mind, especially when the clinical course is inconsistent with the results of biopsy.

The RNAi-mediated silencing of xanthine dehydrogenase impairs growth and fertility and accelerates leaf senescence in transgenic Arabidopsis plants.

Xanthine dehydrogenase (XDH) is a ubiquitous enzyme involved in purine metabolism which catalyzes the oxidation of hypoxanthine and xanthine to uric acid. Although the essential role of XDH is well documented in the nitrogen-fixing nodules of leguminous plants, the physiological importance of this enzyme remains uncertain in non-leguminous species such as Arabidopsis. To evaluate the impact of an XDH deficiency on whole-plant physiology and development in Arabidopsis, RNA interference (RNAi) was used to generate transgenic lines of this species in which AtXDH1 and AtXDH2, the two paralogous genes for XDH in this plant, were silenced simultaneously. The nearly complete reduction in the total XDH protein levels caused by this gene silencing resulted in the dramatic overaccumulation of xanthine and a retarded growth phenotype in which fruit development and seed fertility were also affected. A less severe silencing of XDH did not cause these growth abnormalities. The impaired growth phenotype was mimicked by treating wild-type plants with the XDH inhibitor allopurinol, and was reversed in the RNAi transgenic lines by exogenous supplementation of uric acid. Inactivation of XDH is also associated with precocious senescence in mature leaves displaying accelerated chlorophyll breakdown and by the early induction of senescence-related genes and enzyme markers. In contrast, the XDH protein levels increase with the aging of the wild-type leaves, supporting the physiological relevance of the function of this enzyme in leaf senescence. Our current results thus indicate that XDH functions in various aspects of plant growth and development.

Ellagitannins and lignan glycosides from Balanophora japonica (Balanophoraceae).

Three new ellagitannins named balanophotannins A-C having a 1,1'-(3,3',4,4'-tetrahydroxy)dibenzofurandicarboxyl group in their molecules and four known lignan glycosides were isolated from the extracts of fresh aboveground and underground parts of a medicinal parasitic plant Balanophora japonica (Balanophoraceae). Their structures were elucidated on the basis of spectral and chemical evidence. Chemotaxonomic significance of the known lignan glycosides in Balanophora japonica was discussed.