A new model of tracheal stenosis and its repair with free periosteal grafts.

Stenosis of 50% to 80% of the cervical or thoracic tracheal lumen was created in 17 piglets by encircling the trachea with silicone rubber sheet for 3 to 19 days (median 14 days). In 13 animals thoracic tracheal stenosis was repaired by longitudinal incision and insertion of a free tibial periosteal graft into the defect. An omental pedicle graft was applied to the surface of the free periosteal graft to augment its blood supply in three of these animals. An endotracheal silicone rubber splint was left in place for 2 to 3 weeks after the operations. Four animals served as untreated controls. In 12 of 13 piglets respiratory obstruction was relieved. One repair failed because of graft necrosis. In two animals put to death 1 month and 2 months later, stenosis was absent and the grafts showed variable ossification. The luminal surface had epithelialized. In nine of 10 animals put to death 3 months after the operation, tracheal cross-sectional areas had doubled, stenosis and granulation tissue were absent, and all the grafts had ossified and epithelialized. A mild stenosis (24%) developed over a 2 mm length in one animal and the graft had not ossified. The omental pedicle graft did not improve vascularization of the free periosteal graft. These studies describe a model of tracheal stenosis that can be used to assess various methods of repair. The results indicate that tracheal stenosis can be successfully treated by incision and insertion of a free periosteal graft into the defect.

HIV and HCV infection among drug users in Japan.

AIMS: To assess seroprevalence of human immunodeficiency virus (HIV), hepatitis C virus, injecting drug use, unsafe sexual behaviours, self-mutilation and tattoos in patients attending a drug and alcohol treatment centre in Japan. DESIGN: Cross-sectional survey. SETTING: The work was carried out at the National Sanitarium of Shimousa, Chiba, Japan, a 32-bed inpatient centre specializing in drug and alcohol treatment. MEASUREMENTS: Laboratory analyses for HIV antibody, hepatitis C antibody, hepatitis B antigen and antibody; questionnaires for history of sexual activities, needle and syringe use; physical examination with assessment of self-amputated finger joints, tattoos, scars from lacerations and cigarette burns. FINDINGS: No patients tested positive for anti-HIV. The seroprevalence of anti-HCV positives was 53.8% of methamphetamine-dependent patients, 18.4% of solvent-dependent patients and 5.6% of alcohol-dependent patients. Past needle sharing was reported by 82.1% of methamphetamine-dependent patients, 18.4% of solvent-dependent patients and 5.6% of alcohol-dependent patients. A history of syringe sharing was reported by 87.2% of methamphetamine-dependent patients. More than two-thirds of all patients reported contact with commercial sex workers. Casual sexual contacts were more common among solvent and methamphetamine-dependent patients than those dependent on alcohol. Tattoos and cigarette burns were more common among methamphetamine and solvent-dependent patients than among alcohol-dependent patients. Among the methamphetamine-dependent patients, 20.5% reported self-amputated finger joints compared with none in the other patient groups. CONCLUSIONS: HCV prevalence is a significant problem among methamphetamine users in Japan, probably because of a high rate of needle and/or syringe sharing. Although HIV infection is currently negligible, the very high rate of needle and syringe sharing could give rise to a significant increase in the HIV rate among drug users in the future.

The simple and rapid spectrophotometric determination of trace chromium(VI) after preconcentration as its colored complex on chitin.

Preconcentration method with collection of metal complexes on a chitin has been applied to the spectrophotometric determination of chromium(VI) in water. The chromium(VI) is collected as its 1,5-diphenylcarbazide(DPC) complex on a column of chitin in the presence of dodecyl sulfate as counter-ion. The Cr-DPC complex retained on the chitin is eluted with a methanol-1 M acetic acid mixture (7:3, v/v), and the absorbance of the eluent is measured at 541 nm. Beer's law is obeyed over the concentration range of 0.05-0.6 mug of chromium(VI) in 1 ml of the eluent. The apparent molar absorptivity is 3.5x10(4) dm(3) mol(-1) cm(-1). The tolerance limits for Fe(III) is low, i.e. ten times that of chromium(VI), but some metal ions and common inorganic anions do not interfere in concentration range of 100-10 000 times that of chromium(VI). The present method can be applied to the determination of chromium(VI) in natural water samples.

The spectrophotometric determination of trace molybdenum (VI) after collection and elution as molybdate ion on protonated chitin.

Collection and elution method for inorganic anion on protonated chitin has been applied to the spectrophotometric determination of molybdenum (VI). The molybdenum (VI) is collected as molybdate ion on a column of chitin in weak acidic medium which is easily eluted with a small volume of 0.1 M ammonia buffer solution (pH 10). The molybdenum (VI) in the eluent is determined by bromopyrogallol red-Zephiramine method spectrophotometrically. Beer's law is obeyed over the concentration range of 0.1-0.8 mug of molybdenum (VI) in 1 ml of eluent at 634 nm. The apparent molar absorptivity is 6x10(4) dm(3) mol(-1) cm(-1). The tolerance limits for WO(4)(2-), VO(3)(-), CrO(4)(2-) and Fe (III) is low, that is, 1-100 times that of molybdenum (VI), but some metal ions and common inorganic anions do not interfere in concentration range of 1000-5000 times that of molybdenum (VI). The present method can be applied to the determination of molybdenum (VI) in natural water samples.

Hair analysis for drugs of abuse. VI. The excretion of methoxyphenamine and methamphetamine into beards of human subjects.

The excretion of methoxyphenamine (MOP) and methamphetamine (MA) into beards has been studied. Six healthy male subjects orally took 50 mg of MOP at a single dose and 7 doses for a successive 7 days. Their beard hairs were collected by an electric shaver every morning until MOP disappeared from the beard. After washing with 0.1% SDS, the beard samples were extracted with methanol-5 N HCl (20:1) under ultra-sonication for 1 h and the solution was kept overnight. MOP in the extract was determined by GC/MS using deuterium labelled MOP as an internal standard after trifluoroacetyl-derivatization. The drug concentrations in beard and the reproducibility of analysis were compared with the three procedures, unwashed, 0.1% SDS (wash I) and the additional ethanol (wash II) wash. The drug concentration in beard after SDS wash was 0.5-2.5 ng/mg lower than that in unwashed beard during the first 5-6 days. The drug concentration in beard after ethanol wash was much lower than that in the unwashed beard. The drug excreted into beard was detected 10 approximately 12 days for a single dose and 12-14 days for 7 doses after the last dosage at the cut off level of 1 ng/mg. On the contrary, the drug excreted in urine was not detected after more than 3 days after use. O-Desmethyl MOP, a major metabolite of MOP, was also detected in beard. The procedures were applied to the detection of MA in beard of MA abusers. It was realized that a beard sample was more useful than a urine sample assuming a longer detection.

Hair analysis for drug abuse, Part II. Hair analysis for monitoring of methamphetamine abuse by isotope dilution gas chromatography/mass spectrometry.

Sectional analysis of methamphetamine abuser's hair was performed by using stable-isotope dilution GC/MS method. Drug concentrations of hair shaft cut into 2-cm sections from the root side were compared with the self-reported drug histories of 11 cases and the results of experiments on monkeys. It was found that in nine of the 11 cases, the relationship between the results of sectional analysis and drug histories coincided, but the sectional analyses of two cases were not consistent with self-reported drug history. The difference in drug concentrations between the regions of scalp hair was also investigated. Our study suggests that hair analysis, especially sectional analysis, may be useful in determining past drug history even though it is not exact.

The successful reconstruction of thoracic tracheal defects with free periosteal grafts.

A defect was created in the thoracic trachea in nine piglets (10 kg) by excising a segment from the entire thoracic trachea proximal to the right upper lobe bronchus (3 to 3.5 cm in length) and 30% of the circumference in width (1 to 1.5 cm). The defect was repaired with a free tibial periosteal graft (FPG) and in four piglets an omental pedicle graft (OPG) was applied to the surface of the FPG. An internal tracheal splint was inserted for 12 to 16 days to support the repair and prevent air leak. The splints were removed bronchoscopically. None of the pigs developed signs of airway obstruction at any stage following the repair. Eight were killed 3 months postoperatively when four to six times their original weight. One pig died on the 18th postoperative day of unknown cause. The tracheas were removed, x-rayed, and examined grossly and histologically. The results demonstrated normal tracheal growth with absence of either stenosis, collapse, or granulation tissue. All grafts were viable, bone formation was present, and the lumenal surfaces were lined with columnar and respiratory epithelium. The OPG did not improve vascularization of the FPG. This model suggests that tracheal stenosis in children may be surgically corrected by simply incising the stenotic segment longitudinally and enlarging the tracheal diameter by inserting a FPG into the defect.

Interaction of indometacin farnesil, a new nonsteroidal antiinflammatory drug with peripheral blood mononuclear cells from patients with rheumatoid arthritis.

Indometacin farnesil (Indo-F) is a prodrug of indomethacin designed to reduce the occurrence of side-effects by esterification of the carboxyl group on indomethacin with farnesol. We have examined the pharmacological kinetics and action of Indo-F in peripheral blood mononuclear cells (PBMNC) and polymorphonuclear leukocytes (PBPNL) from patients with rheumatoid arthritis (RA). PBMNC and PBPNL were obtained from 31 RA patients. Indo-F was incubated with PBMNC or PBPNL in the presence or absence of granulocyte-macrophage colony stimulating factor (GM-CSF) (100 pg/ml) for 3 approximately 7 days, after which the concentrations of Indo-F and indomethacin in the culture supernatants or in the cytoplasm extracts were measured with HPLC. The levels of Indo-F in the culture supernatants were significantly decreased in the presence of PBMNC or PBPNL from either normal individuals or RA patients. Indo-F was found to be taken up by PBMNC as well as by PBPNL from RA patients. Conversion of Indo-F into indomethacin was significantly enhanced by GMCSF in the presence of PBMNC, but not PBPNL. The results indicate that Indo-F is taken up by peripheral blood leukocytes from RA patients. Moreover, the data suggest that monocyte-lineage cells might play an important role in the conversion of Indo-F into indomethacin since GM-CSF markedly facilitated the conversion in the presence of PBMNC, but not PBPNL.

A newborn with a covered anus complicated by two concomitant unique fistulas.

A newborn having a covered anus and two fistulas, one ano-urethral and one penile urethro-cutaneous, is presented. In spite of the resemblance of this ano-urethral fistula to an "H-type" ano-urethral fistula, which is thought to result from the failure of the division of the cloaca in the embryological period, three abnormalities seen in this case were thought to be the result of a serial event which occurred in the more distal part, the anal and the genital folds, during the embryological period.

Volvulus of the transverse colon in a four-year-old boy.

A 4-year-old boy with a volvulus of the transverse colon is presented. The mildness of the obstruction made direct visualization of the twisted loop with barium enema possible. At laparotomy a congenital band between the transverse colon and the small intestine was found to have been the predisposing factor of the volvulus.

Effect of esophageal ligation on the growth of fetal rabbits.

Controversy continues regarding the nutritional value to the fetus of swallowed amniotic fluid. To clarify this issue further, esophageal ligations were performed to prevent deglutition in utero in 63 fetal rabbits during the final trimester of pregnancy. Compared with sham-operated littermate controls, the fetuses that were ligated for periods of 4, 5, or 6 days showed significant reductions in weight of 6.1, 18.9, and 9.2%, respectively. These results compare well with the magnitude of weight reduction seen clinically in patients with esophageal atresia. Significant but less consistent reductions were also noted in crown-rump length and biparietal diameter. No significant differences were seen in either body composition or gastrointestinal tract histology. These results indicate that swallowed amniotic fluid does play a role in fetal nutrition and may be particularly important in the later stages of gestation when placental function is limited.