Measurement of hydrocarbon-degrading microbial populations by a 96-well plate most-probable-number procedure.

A 96-well microtiter plate most-probable-number (MPN) procedure was developed to enumerate hydrocarbon-degrading microorganisms. The performance of this method, which uses number 2 fuel oil (F2) as the selective growth substrate and reduction of iodonitrotetrazolium violet (INT) to detect positive wells, was evaluated by comparison with an established 24-well microtiter plate MPN procedure (the Sheen Screen), which uses weathered North Slope crude oil as the selective substrate and detects positive wells by emulsification or dispersion of the oil. Both procedures gave similar estimates of the hydrocarbon-degrader population densities in several oil-degrading enrichment cultures and sand samples from a variety of coastal sites. Although several oils were effective substrates for the 96-well procedure, the combination of F2 with INT was best, because the color change associated with INT reduction was more easily detected in the small wells than was disruption of the crude oil slick. The method's accuracy was evaluated by comparing hydrocarbon-degrader MPNs with heterotrophic plate counts for several pure and mixed cultures. For some organisms, it seems likely that a single cell cannot initiate sufficient growth to produce a positive result. Thus, this and other hydrocarbon-degrader MPN procedures might underestimate the hydrocarbon-degrading population, even for culturable organisms.

Effect of race and gender on neurological level in myelomeningocele.

The association of race and gender with different neurological levels of myelomeningocele was studied in 251 patients. Over-all, the white to black ratio was 3.6 and the male to female ratio was 0.86. However, the proportions of whites and females were significantly increased in thoracic-level patients (white to black ratio 13.6, male to female ratio 0.43), whereas the lumbar-level patients had sex and white to black ratios equivalent to the area population. This supports the concept that thoracic-level myelomeningocele has a different pathogenesis from lumbar-level.

Bone density in myelomeningocele: the effects of ambulatory status and other factors.

Measurements were made of distal radius, mid-radius, tibia and metatarsal bone-density of 80 patients with myelomeningocele (17 thoracic, six L1/L2, 13 L3, 30 L4, 14 L5/sacral). For the upper extremity the bone density primarily was low in the thoracic patients, but in the tibia and metatarsal it showed a more linear correlation with neurological levels. The effect of age was highly significant at all sites; after controlling for this, the neurological level was a significant determinant of bone density at all sites, and this effect was greater in older children. Patients with impaired ambulation had decreased bone-density in the distal radius, tibia and metatarsal, but not in the mid-radius. Race had no significant effect on density after accounting for differences in neurological level. Weight for height and multiple fractures did not correlate with bone density. Although ambulatory status (weight-bearing stresses) and neurological status (muscle stresses) are both important factors in bone density, this study suggests that the latter is a more important determinant.

Hydronephrosis in the asymptomatic neonate with myelodysplasia.

Early diagnosis and intervention in the child with myelodysplasia can effectively improve and preserve renal function in those newborns presenting with abnormalities at birth or who are at risk for deterioration of renal function from infection, vesicoureteral reflux and/or obstruction. During a 1-year period 10 newborns with myelodysplasia were seen. Hydronephrosis was present in 6, reflux in 3 and urinary tract infection in 3. In each newborn adequate decompression of the bladder and complete resolution of the hydronephrosis were achieved. Uroradiographic evaluation was helpful in determining the best mode of therapy for each individual.

Selective cyanosis of the right arm. Isolation of right subclavian artery from aorta with bilateral ductus arteriosus and pulmonary hypertension.

A sixteen-month-old child presented with cyanosis of the right arm. Investigation revealed bilateral persistent ductus arteriosus with isolation of the right subclavian artery from the aorta. Pulmonary vascular resistance and pulmonary arterial pressure were elevated so that the right subclavian artery received desaturated blood from the right pulmonary artery via the persistent right ductus arteriosus.

The Langer-Giedion syndrome: report of a 22-year old woman.

A 22-year-old woman with the Langer-Giedion syndrome and delayed puberty is presented. Pertinent features include a bulbous nose, sparse hair, protruding ears, multiple cartilaginous exostoses, cone-shaped phalangeal epiphyses, short stature, microcephaly, and mental retardation. She is the oldest patient thus far described with this condition, and is compared to the ten previously published cases. The clinical course of patients with the Langer-Giedion syndrome and the possibility of malignant change in the exostoses have not been established.

Tricuspid atresia: corrective operation without a bioprosthetic valve.

A case of successful correction of type IB tricuspid atresia is described in which the patient's own normal pulmonary valve was used in its natural location. Morphological features of tricuspid atresia suggest that use of the in situ pulmonary valve is possible in most patients with normally related great arteries. Elimination of the requirement for valved conduits and bioprosthetic valves may eventually permit corrective operation in the very young child.