Active observation in management of acute abdominal pain in childhood.

Out of 363 children admitted to a surgical unit with acute abdominal pain only 126 (35%) had an operation. Of these, 20 first underwent a period of "active observation." This procedure, used to help reach a diagnosis or decision in doubtful cases, is safe and useful and may be applied at home or in hospital.     

Role of doxapram in reducing pulmonary complications after major surgery.

In a double-blind study patients given a single dose of doxapram 1-5-2-0 mg/kg combined with morphine postoperatively had a significantly lower incidence of reflex postoperative cough and expectoration of purulent sputum than patients given morphine alone. They also had significantly higher arterial oxygen tensions five days postoperatively. Smaller differences were found with naloxone combined with morphine.     

Antibody-coated bacteria in the urine of preschool and school-aged girls with asymptomatic bacteriuria.

Urine samples from 3564 girls aged 2 to 13 years were screened for evidence of infection. Cultures were positive (bacteria count, more than 10(5)/ml) in 61 (1.7%) by the dipslide method and in 55 (1.5%) by standard culture techniques. In 13 (23.6%) of the 55, antibody-coated bacteria (ACB) were detected in the urine. The clinical, bacteriologic, radiologic and urinalysis findings in children with ACB were no different from those in children in whom the bacteria were not coated. Direct examination of uncentrifuged urine under high power revealed one or more bacteria per two high-power fields in 96% of infected urine samples and in only 7% of noninfected samples. Five or more leukocytes per high-power field in centrifuged urine were detected in 36.7% of infected urine samples but not in noninfected samples. The ACB test did not differentiate between asymptomatic bacteriuria with parenchymal scarring or vesicoureteral reflux or both and asymptomatic bacteriuria without these abnormalities.     

The separation of ribonucleic acids from Escherichia coli on lysin-agarose.

Lysine-agarose provides a simple means of separating RNA species of different moleecular weight. When RNA from Escherichia coli is added to a small column of lysine-agarose and elution is carried out at neutral pH with a shallow linear gradient of NaCl the RNA species are eluted according to size; 4S and 5S RNA species are completely separated and after a delay the 16S and 23S species are eluted as separate peaks. The process is very reproducible and the different species are eluted at a fixed salt concentration even when changes are made in the gradient, provided other conditions, under which the column is run remain constant.     

The complete amino acid sequence of the major component myoglobin of Amazon river dolphin (Inia geoffrensis).

The complete amino acid sequence of the major component myoglobin from Amazon River dolphin, Inia geoffrensis, was determined by specific cleavage of the protein to obtain large peptides which are readily degraded by the automatic sequencer. Three easily separable peptides were obtained by cleaving the protein with cyanogen bromide at the methionine residues and four peptides were obtained by cleaving the methyl-acetimidated protein with trypsin at the arginine residues. From these peptides over 85% of the sequence was completed. The remainder of the sequence was obtained by fragmentation of the large cyanogen bromide peptide with trypsin. This protein differs from that of the common porpoise, Phocoena phocoena, at seven positions, from that of the common dolphin, Delphinus delphis, at 11 positions, and from that of the sperm whale, Physeter catodon, at 15 positions. By comparison of this sequence with the three-dimensional structure of sperm whale myoglobin it appears that those residues close to the heme group are most conserved followed by those in nonhelical regions and lastly by those in the helical segments. All of the substitutions observed in this sequence fit easily into the three-dimensional structure of the sperm whale myoglobin.     

Water flow dynamics in the respiratory tract of the carp (Cyprinus carpio L.).

Simultaneous measurements of water velocity in the buccal chamber, and buccal and opercular hydrostatic pressure of carp have revealed surprisingly high water velocities. The high flow velocities mean that, at times, the kinetic energy of flow makes a substantial contribution to the total fluid energy. This suggests that there may be unequal distribution of hydrostatic pressures within the buccal chamber. Anatomical examinations showed that fluid channels in the buccal chamber and gill raker sieve are complex and can be expected to vary spatially and temporally throughout the respiratory cycle. It appears that there is a potential for error in many of the previous analyses of 'gill resistance and energetics of fish breathing based solely on hydrostatic pressure measurements and the simplifying assumption of steady-state conditions.     

Aldosterone dynamics during graded exercise at sea level and high altitude.

Hormonal responses to graded exercise of eight low altitude residents were examined at sea level (SL) and after 1 (acute) and 11 (chronic) days at 4,300 m (HA). Caloric, water, and electrolyte intakes were controlled, as were temperature and humidity. Blood was sampled at rest and during light and moderate upright bicycle exercise (20 min at 40% and 75% of maximal O2 uptake, respectively). Mean VO2 max at HA was 27% lower than at SL. Resting plasma levels of aldosterone (Aldo), renin, and angiotensin II (A II) were significantly lower (P smaller than 0.05) on day 1 at HA compared to SL, but returned to SL values by day 11. Plasma cortisol values at rest were similar at SL and HA and were not significantly altered by light or moderate exercise. Renin, A II, and Aldo rose progressively with increasing workload in each environment. With acute HA, renin and Aldo were lower than at either SL or chronic HA. The chronic HA levels tended to approximate SL findings, implying adaptation. The data suggest that aldosterone is predominantly under the control of the renin-angiotensin system during graded exercise at sea level and that the response of this system is altered on acute high-altitude exposure.