ABSTRACT
We report a case of cerebellum abscess due to Fusobacterium nucleatum(F. nucleatum) in a 60-year-old man. He was admitted to our hospital complaining of headache and dizziness. On admission, he was lucid with the following vital data:blood pressure, 136/89 mmHg;heart rate, 65 beats/min;body temperature, 37.0â;and oxygen saturation, 100%. He had a moderate headache and could not walk straight. In general, there were no abnormal findings except for his poor dental hygiene. Laboratory findings revealed elevated white blood cell counts(10,900/mm3)and brain MRI revealed a mass shadow that was suspected to be an abscess in the left side of his cerebellum. Elective surgery was scheduled. However, consciousness of disorder was observed on the second hospital day and the size of mass shadow extended;hence, emergent drainage under craniotomy was performed. The diagnosis was cerebellum abscess, and F. nucleatum, which is a normal flora in the oral cavity, was isolated in his cerebellum abscess. After the surgery, his hospital course was positive under the treatment of antibiotics for F. nucleatum. The route of bacterial infection entry was unclear;however, it will be considered that abscesses in the central nervous system occur because of poor dental hygiene.
Subject(s)
Brain Abscess , Fusobacterium Infections , Fusobacterium nucleatum , Oral Hygiene , Brain Abscess/etiology , Cerebellum , Fusobacterium Infections/etiology , Fusobacterium nucleatum/isolation & purification , Humans , Male , Middle AgedABSTRACT
PURPOSE: To investigate mechanisms governing the stabilization and destabilization of immunoglobulin (IgG1) by arginine (Arg). METHODS: The effects of Arg on the aggregation/degradation, thermodynamic stability, hydrophobicity, and aromatic residues of IgG1 were respectively investigated by size-exclusion chromatography, differential scanning calorimetry, probe fluorescence, and intrinsic fluorescence. RESULTS: Arg monohydrochloride (Arg-HCl) suppressed IgG1 aggregation at near-neutral pH, but facilitated aggregation and degradation at acidic pH or at high storage temperature. Equimolar mixtures of Arg and aspartic acid (Asp) or glutamic acid (Glu) suppressed aggregation without facilitating degradation even at high temperature. Arg-HCl decreased the thermodynamic stability of IgG1 by enthalpic loss, which was counteracted by using Asp or Glu as a counterion for Arg. The suppression of aggregation by Arg-HCl was well correlated with the decrease in hydrophobicity of IgG1. The intrinsic fluorescence of IgG1 was unaffected by Arg-HCl. CONCLUSIONS: Suppression of IgG1 aggregation can be attributed to the interaction between Arg and hydrophobic residues; on the other hand, facilitation of aggregation and degradation is presumably due to the interaction between Arg and some acidic residues, which could be competitively inhibited by simultaneously adding either Asp or Glu.
Subject(s)
Arginine/chemistry , Immunoglobulin G/analysis , Immunoglobulin G/chemistry , Thermodynamics , Drug Stability , Fluorescence , Humans , Spectrometry, Fluorescence/methodsABSTRACT
Optically active 1,2-bis(alkylmethylphosphino)ethanes and bis(alkylmethylphosphino)methanes are unique diphosphine ligands combining the simple molecular structure and P-stereogenic asymmetric environment. This work shows that these ligands exhibit excellent enantioselectivity in rhodium-catalyzed asymmetric hydrogenation of alpha,beta-unsaturated phosphonic acid derivatives. The enantioselective hydrogenation mechanism elucidated by NMR study is also described.
