ABSTRACT
We aimed to establish prevailing consultant opinion on the management of children with a history suggestive of foreign body (FB) aspiration but no clinical or radiological findings. FB aspiration is a common problem in children. Most agree that bronchoscopy should be performed if a child has clinical or radiological signs. With suggestive history but no such signs, the decision is more difficult; both bronchoscopy and neglected FBs have the potential for serious consequences. A postal questionnaire was sent to all British Association of Otolaryngologists and Head and Neck Surgeon (BAO-HNS) consultants. The 563 questionnaires sent elicited a 63% reply rate. With suspected organic FBs, 52% would bronchoscope immediately, 38% would observe, and 10% would discharge. With suspected inorganic FBs, 35% would bronchoscope, 42% would observe, and 23% would discharge. Thus, the majority suggest admission, showing a preference for bronchoscopy with a history of organic FB, and observation if inorganic. Unless justified, it may be unacceptable to discharge these patients.
Subject(s)
Foreign Bodies/therapy , Inhalation , Bronchoscopy , Child, Preschool , Humans , Infant , Otolaryngology , Practice Patterns, Physicians' , Surveys and Questionnaires , United KingdomABSTRACT
The genealogy of 14 H-2Kb mutations arising spontaneously in the C57BL/6Kh colony is presented together with data from skin-graft monitoring and husbandry procedures. Eight of the 14 mutations have phenotypic and structural similarities, but the pedigree analysis and evaluation of the histocompatibility genetics of their sibs and ancestors strongly indicate that they represent recurring mutational events rather than the segregation of a single mutation throughout the colony.
Subject(s)
H-2 Antigens/genetics , Mice, Inbred C57BL/genetics , Mutation , Animal Husbandry/methods , Animals , Female , Male , Mice , Phenotype , Skin Transplantation , Time FactorsABSTRACT
The induction of histocompatibility gene mutations in BALB/cKh mouse sperm was determined following doses of 0, 350, or 350 + 300 rad (24 h apart) of 250 kV X-rays. The mutation rate is significantly lower than predicted on the basis of the seven-locus test and is not significantly different from the very low rate of H-loci in BALB/cKh spermatogonia. Furthermore, selection and repair are important in determining mutation rates per viable progeny of H-loci during both spermatogenesis and gestation.
Subject(s)
Genes/radiation effects , H-2 Antigens/genetics , Mutation , Spermatogonia/radiation effects , Spermatozoa/radiation effects , Animals , Dose-Response Relationship, Radiation , Male , Mice , Mice, Inbred BALB C/genetics , X-RaysABSTRACT
Adult Balb/c Kh male mice were irradiated (pelvic region, 250 kVcp X-rays, 60 rad per min) and three months later were mated to untreated C57BL/6 Kh females. Their B6C F1 progeny were screened for mutations at the Class II histocompatibility loci, i.e. those that carry similar alleles in the parental lines and are therefore homozygous in the F1 progeny. The treatment groups were: single doses of 0, 350, 500, 650 and 800 rad; split doses 1 day apart, totalling 500, 650 and 800 rad; split doses averaging 52 days apart, totalling 650 and 800 rad. Thirty-six mutants were identified in 13,614 progeny. Twelve of them occurred in five clusters of two or three, presumably owing to five gonadal mosaics among 940 parents. Irradiation did not increase the spermatogonial mutation rate. The only effect of exposure appeared to be a decrease in the mutation rate of the 1-day split dose-groups compared to those with the same total doses in a single exposure or in two fractions, 52 days apart.
