Role of LPS length in clearance rate of bacteria from the bloodstream in mice

Strains of Pseudomonas aeruginosa isolated from patients with cystic fibrosis (CF) never spread systemically. This may be due to serum sensitivity since these strains are very sensitive to complement-mediated bactericidal activity. A serum-resistant mutant, P. aeruginosa TUM3 HSR, was obtained from serum-sensitive strain TUM3 from a CF patient in order to clarify the mechanism of failure of systemic spread. LPS profiles on silver-stained gels and immunological analysis revealed that a long O-polysaccharide side chain was overproduced on the LPS molecules of TUM3 HSR as compared with the LPS of TUM3. The clearance rate from the bloodstream in mice was compared in the two strains. The number of TUM3 bacteria in 1 ml of blood, 10 min after injection into the tail vein, significantly decreased from 1.7 x 10(8) to 3.7 x 10(5) c.f.u. ml-1. In contrast, TUM3 HSR was not eliminated during the same period (decrease from 1.9 x 10(8) to 3.4 x 10(7) c.f.u. ml-1). Interestingly, these isogenic strains were not killed by 40% murine serum, probably reflecting immaturity of the complement-mediated killing system in mice. These results pointed to a correlation between LPS structure and blood clearance rate in mice. This was confirmed by examining blood clearance kinetics using the smooth-LPS strain Salmonella typhimurium LT2 and LPS-deficient mutants derived from it. S. typhimurium LT2 resisted blood clearance while the LPS-deficient mutants were cleared rapidly. None of the S. typhimurium strains were killed by murine serum. The number of P. aeruginosa TUM3 and S. typhimurium LPS-deficient mutants trapped in the liver following injection into the peripheral circulation was greater than that of their counterparts.(ABSTRACT TRUNCATED AT 250 WORDS)

[A case of laryngeal and tracheobronchial tuberculosis]

The patient was 38-year-old male. His chief complaint was persistent cough. He had been diagnosed at an another clinic as tuberculosis by positive sputum culture. Laboratory findings at the first examination were as follows: ESR was 10 mm/1 hr and CRP was 0.920 mg/dl and other data were within normal limits. Chest X-ray showed infiltrative shadow in the left lower lobe. Bronchoscopic findings before treatment were as follows: there were ulcers on bilateral vocal cords, small white nodules with reddness in trachea and red nodules and white coated ulcers in left main bronchus. He was treated with combination chemotherapy (INH, RFP, EB) and the steroid inhalation was added 1 month later after the initiation of chemotherapy. Bronchoscopic findings at 2 months after starting chemotherapy were as follows: lesions of vocal cords and trachea were improved and lesion of left main bronchus was scarred without stenosis. Bronchial stenosis as sequelae of endobronchial tuberculosis deteriorates the patients' quality of life. Therefore it is important to diagnose endobronchial tuberculosis early and to start treat with chemotherapy as soon as possible, and the follow up by bronchoscopy should be done during treatment.

The prevalence and retention of lead pellets in Japanese quail

Thirty-six Japanese quail (18 control birds, 18 lead-dosed birds) were used. The 18 quail were dosed with #4 lead weight that were orally inserted into the proventriculus. Delta-aminolevulunic acid dehydrase (ALAD) activity in erythrocytes in the dosed quail decreased 90% (p < 0.01) after one week as compared with the undosed quail. This inhibition of ALAD activity in erythrocytes indicates lead exposure. Radiographics were obtained at 0, 1, 4, 9, 22, and 32 days. The lead pellets remained in the gizzard and became smaller in 4 days. At day 22, after the lead treatment, in 8 quail of the treated quail 12, the lead pellets disappeared. At day 32, all lead pellets disappeared. These findings indicate that the ingested lead pellets are absorbed gradually in the intestine. The lead concentrations in the blood, liver, kidney, and femur of the lead-dosed quail were significantly higher than in the undosed quail until the 6th week. At week 2, the lead concentration of the proventriculus, gizzard, gizzard contents, duodenum, small intestine, and cecum in the dosed quail was significantly higher. Lead concentration of feces was significantly higher at weeks 2 and 4 (p < 0.01). Throughout this study, no lead pellets were found in the feces.

[Determination of yohimbine in serum by high performance liquid chromatography]

An automated method for determination of yohimbine (Yoh) in the serum was developed by means of column switching high performance liquid chromatography (HPLC). TSK-precolumn BSA-ODS and TSK-gel ODS-120T were used as a precolumn and analytical column, respectively. The wavelengths of detection were used at 280 nm (excitation) and 360 nm (emission). A 100 microliter serum sample is directly injected onto the precolumn. Yoh is then eluted within 30 min with an methanol-potassium phosphate buffer mixture. The analytical recoveries (99.3-110.4%), reproducibilities (within-run, C.V. less than 2.27%), and detection limit (0.80 ng/ml, S/N = 3) indicate that this system is suited for determination of Yoh. The five healthy volunteers received a single oral dose 10 mg of HYoh powder. The average of the maximal serum concentration and the area under the curve (AUC) from 0 to 4 h were 10.3 +/- 0.88 ng/ml and 19.70 +/- 0.87 ng.h.ml-1, respectively. The elimination rate constant (Kc1) was 0.52 +/- 0.03 h, and biological half-life (t1/2el) was 1.32 +/- 0.12 h.