A Case of Seizure Revealing Fahr's Syndrome with Primary Hypoparathyroidism.

BACKGROUND Idiopathic basal ganglia calcification, also known as Fahr's disease or Fahr's syndrome, is a rare neurological disorder characterized by abnormal calcified deposits in the basal ganglia. Here, we report a case of Fahr's syndrome with calcification of the basal ganglia due to hypoparathyroidism in a patient with seizures. CASE REPORT A 52-year-old male patient visited our clinic with seizures. Brain computed tomography (CT) showed bilateral symmetrical calcifications in cerebellar white matter, the corpus striatum, the posterior thalami, and the centrum semiovale of both cerebral hemispheres. He had symptoms of hypocalcemia and low parathyroid hormone levels. The patient was diagnosed with Fahr's syndrome due to primary hypoparathyroidism. He underwent calcium supplementation and calcifediol treatment. His symptoms improved, and he was discharged from the hospital. CONCLUSIONS In patients with hypocalcemia accompanied by parathyroid dysfunction, neurological examination and CT should be performed to confirm abnormal intracranial calcification.

Cyclization mechanism of amorpha-4,11-diene synthase, a key enzyme in artemisinin biosynthesis.

Cyclization of farnesyl diphosphate into amorpha-4,11-diene by amorpha-4,11-diene synthase (ADS) initiates biosynthesis of artemisinin, a clinically important antimalarial drug precursor. Three possible ring-closure mechanisms, two involving a bisabolyl carbocation intermediate followed by either a 1,3-hydride shift or two successive 1,2-shifts, and one involving a germacrenyl carbocation, were proposed and tested by analyzing the fate of farnesyl diphosphate H-1 hydrogen atoms through (1)H and (2)H NMR spectroscopy. Migration of one deuterium atom of [1,1-(2)H(2)]farnesyl diphosphate to H-10 of amorpha-4,11-diene singled out the bisabolyl carbocation mechanism with a 1,3-hydride shift. Further confirmation was obtained through enzyme reactions with (1R)- and (1S)-[1-(2)H]farnesyl diphosphate. Results showed that deuterium of the 1R compound remained at H-6, whereas that of the 1S compound migrated to H-10 of amorpha-4,11-diene. Incorporation of one deuterium into amorphadiene in the cyclization process was observed when the reaction was performed in (2)H(2)O, as evidenced by an increase of 1 amu in the mass of the molecular ion.

Structure determination of a new lupane-type triterpene, tiarellic acid, isolated from Tiarella polyphylla.

A new 27-carboxylic lupane-type triterpene, tiarellic acid (1), was isolated from Tiarella polyphylla together with corosolic acid (2) and tormentic acid (3). Tiarellic acid was characterized as 3,23-dihydroxy-20(29)-lupen-27-oic acid and its NMR data were unambiguously assigned using 2-D NMR techniques.