Compound-compound interaction analysis of baicalin and berberine derivatives in aqueous solution.

Baicalin and berberine are biologically active constituents of the crude drugs Scutellaria root and Coptis rhizome/Phellodendron bark, respectively. Baicalin and berberine are reported to combine together as a 1:1 complex that forms yellow precipitates by electrostatic interaction in decoctions of Kampo formulae containing these crude drugs. However, the structural basis and mechanism for the precipitate formation of this compound-compound interaction in aqueous solution remains unclarified. Herein, we searched for berberine derivatives in the Coptis rhizome that interact with baicalin and identified the chemical structures involved in the precipitation formation. Precipitation assays showed that baicalin formed precipitates with berberine and coptisine but not with palmatine and epiberberine. Thus, the 2,3-methylenedioxy structure may be crucial to the formation of the precipitates, and electrostatic interaction is necessary but is not sufficient. In this multicomponent system experiment, palmatine formed a dissociable complex with baicalin and may competitively inhibit the formation of berberine and coptisine precipitation with baicalin. Therefore, the precipitation formed by berberine and baicalin was considered to be caused by the aggregation of the berberine-baicalin complex, and the 2,3-methylenedioxy structure is likely crucial to the aggregation of the complex.

Pandemic influenza A-associated acute necrotizing encephalopathy without neurologic sequelae.

We describe an 8-year-old girl with the mildest form of acute necrotizing encephalopathy, associated with pandemic influenza A. She manifested a convulsion engendering deterioration of consciousness, although cranial computed tomography and magnetic resonance imaging within 4 hours after the convulsion revealed no abnormalities. Cranial magnetic resonance imaging 20 hours after the convulsion revealed lesions of the thalamus bilaterally, brainstem tegmentum, internal capsule, and white matter. She was diagnosed with acute necrotizing encephalopathy. Typically, the prognosis of acute necrotizing encephalopathy with a brainstem lesion is poor. Nevertheless, she recovered almost completely, after early intervention with pulsed methylprednisolone and high-dose γ-globulin therapy. She manifested a thermolabile phenotype of carnitine palmitoyltransferase II variants such as cystine-isoleucine-methionine phenotype type 9 (FVM-CIM; Phe352Cys-Val388Ile-Met647Met alleles), resulting in a predisposition to encephalopathy during influenza infection. This case is the first, to the best of our knowledge, of pandemic influenza A-associated acute necrotizing encephalopathy with a good outcome despite severe magnetic resonance imaging findings.

Removal of methylene blue from aqueous solution using a polarizable nanolayered manganese oxide film.

A layered manganese oxide film grown electrochemically was applied to remove methylene blue (MB), a cationic dye, from an aqueous solution. A layered MnO(x) film intercalated with tetraethylammonium (Et(4)N) cations was deposited potentiostatically at +1.0 V (vs. Ag/AgCl) from an aqueous Mn(2+) solution containing Et(4)NCl. Et(4)N cations were sandwiched between negatively charged MnO(x) layers. When the Et(4)N/MnO(x) film was immersed in a solution containing MB alone, the intercalated Et(4)N cations were replaced with MB in a solution phase by an ion-exchange mechanism. The uptake capacity of the Et(4)N/MnO(x) film for MB was estimated to be 45.3 mg per 1.0 g of MnO(2). In the presence of KCl, the MB sorption was seriously restricted because the interlayer space was occupied by K(+) ions. However, the MnO(x) film anodized at +0.8 V can selectively take up MB molecules from the KCl solution. This can be ascribed to an increase in the interlayer space available to the sorption of MB due to the extraction of K(+) ions, where the MnO(x) surface probably has a specific affinity toward MB molecules.