A Case of Obstetrical DIC Probably Due to Uterine Type of Amniotic Fluid Embolism during Cesarean Section

A 42-year-old woman diagnosed as marginal placenta previa underwent cesarean section and bilateral tubal ligation under general anesthesia in 37th gestational week. Uterine contraction after delivery was good, but atonic bleeding progressed during tubal ligation. Oxytocic drugs were ineffective. We suspected obstetrical DIC and started treatment for DIC immediately, but the bleeding lasted. After total hysterectomy, she had stable vital signs. She broke away from DIC immediately after surgery. Intraoperative findings were satisfied the criteria for clinical uterine type amniotic fluid embolism (AFE). Although AFE indicates a bad prognosis, we saved her without any sequelae

Quantitative determination of erlotinib in human serum using competitive enzyme-linked immunosorbent assay

A selective and sensitive competitive enzyme-linked immunosorbent assay (ELISA) method was developed and validated for the quantification of erlotinib in 50 µL of samples of human serum. Anti-erlotinib serum was obtained by immunizing mice with an antigen conjugated with bovine serum albumin and 3,4-bis(2-methoxyethoxy)benzoic acid using the N-succinimidyl ester method. Enzyme labeling of erlotinib with horseradish peroxidase was similarly performed using 3,4-bis(2-methoxyethoxy)benzoic acid. A simple competitive ELISA for erlotinib was developed using the principle of direct competition between erlotinib and the enzyme marker for anti-erlotinib antibody, which had been immobilized on the plastic surface of a microtiter plate. Serum erlotinib concentrations lower than 40 ng/mL were reproducibly measurable using the ELISA. This ELISA was specific to erlotinib and showed very slight cross-reactivity (6.7%) with a major metabolite, O-desmethyl erlotinib. Using this assay, drug levels were easily measured in the blood of mice after oral administration of erlotinib at a single dose of 30 mg/kg. ELISA should be used as a valuable tool for therapeutic drug monitoring and in pharmacokinetic studies of erlotinib. Keywords: Erlotinib, Enzyme-linked immunosorbent assay, O-desmethyl erlotinib, Tyrosine-kinase inhibito

Light-Microscopic Immunocytochemistry for Gentamicin and Its Use for Studying Uptake of the Drug in Kidney▿

Gentamicin (GM) is a widely used antibiotic but shows renal toxicity. We produced a serum against GM (anti-GM) conjugated to bovine serum albumin with N-(gamma-maleimidobutyryloxy)succinimide. The antiserum was monospecific for GM and did not cross-react with the analog streptomycin, tobramycin, kanamycin, or amikacin. The antiserum also detected glutaraldehyde-fixed GM, and this enabled us to develop an immunocytochemical method for detecting the uptake of GM in rat kidney. Twelve hours after a single intravenous administration of GM, immunocytochemistry revealed that GM accumulated in the S1, S2, and S3 segments of the proximal tubules, as well as in the distal tubules and collecting ducts. By 12 h after injection, the drug was detected in cytoplasmic granules of the proximal tubule cells. However, early (1 h) after injection, drug accumulation was detected in the microvilli of these cells. The distal tubules and collecting ducts contained scattered swollen cells, reminiscent of necrotic cells, in which both the nuclei and the cytoplasm reacted strongly with GM. No staining occurred in the kidneys of saline-injected control rats. These results agree with previous studies showing that GM is endocytosed in the proximal tubules and accumulates in lysosomes. Additionally, our results show that GM also accumulates in the distal tubules and collecting ducts. This was achieved by systematically varying the pretreatment conditions—an approach necessary for detecting GM in different subcellular compartments. This approach should be useful for accurately detecting the uptake and toxicity of the antibiotic in different tissues