Studies on the Dombrock blood group system in non-human primates.

The Dombrock blood group system consists of five distinct antigens: two antithetical antigens, Doa and Dob, and three high-frequency antigens:Gya,Hy, and Joa. Although the prevalence of Doa and Dob in different populations makes them useful as genetic markers, the scarcity of reliable antibodies to these antigens has prevented this potential from being realized. The gene (DO;ART4) encoding the Dombrock glycoprotein has been cloned and sequenced, and the molecular bases of the various Dombrock phenotypes have been determined. The purpose of this study was to perform DNA-based assays on the DO homolog in non-human primates to determine the degree of conservation in the DO gene. Murine MoAbs to Dombrock protein were developed by standard hybridoma technologies and used to test RBCs from non-human primates by hemagglutination. PCR-RFLP analysis for the six single-nucleotide polymorphisms (SNPs) that have been defined in human alleles were performed on DNA extracted from fresh or frozen blood samples from numerous non-human primates. Hemagglutination tests with six MoAbs to the Dombrock glycoprotein revealed distinct epitopes on RBCs from the non-human primates. The gorillas and orangutans had the same PCR-RFLP digestion pattern for the six SNPs studied as chimpanzees. Old world monkeys (macaques) were identical at nucleotides (nt) 323, 350, 624, and 793 with the chimpanzees, and at nt 898 the digestion pattern was the same as for the HY1 allele in humans. For the new world monkeys (tamarins and squirrel monkeys) the digestion pattern was conserved for nt 793 but different for nt 624; the other SNPs could not be determined because there was no amplification. The presence of epitopes recognized by the MoAbs and PCR-RFLP results among the non-human primates shows considerable conservation of the DO gene. The difficulties we encountered with the amplification of DNA from the non-human primates lower in the phylogenetic tree are probably due to divergence in sequence.

Ventricular dominance patterns in preterm infants.

OBJECTIVE: The purpose of the study was to determine EKG and 2-D echocardiographic criteria of ventricular dominance in preterm infants and select those by which ventricular dominance could be established by EKG alone. METHODS: A database was constructed from EKG and 2-D echocardiographic measurements on preterm infants ranging in gestational ages from 23 to 34 weeks and birth weights from 555-2490 g, and fullterm controls. Twelve-lead EKGs were obtained in the first 4 days of life in 12 preterm infants and in the first 24 hours of 4 controls. 2-D echocardiograms were performed with sweeps from the subcostal, parasternal, apical and suprasternal views and M-mode measurements in the short axis parasternal view on 11 of the preterm infants and 9 fullterm controls. RESULTS: A definite leftward QRS axis for the preterm infants (+90 degrees, preterm; +133.75 degrees, term; t = -5.63; p < 0.001) indicated a left ventricular (LV) dominance. But R/S in favor of LV dominance for preterm infants was apparent in V6 only. A pooled amplitude index for each ventricle based on R and S wave from V1, V2, V5, and V6 leads, showed LV dominance for the preterm infants with a trend toward RV dominance with increasing gestational age (F = 20.82; p < 0.001). RVD/LVED M-mode echo ratios confirmed the LV dominance in preterm infants. CONCLUSION: A healthy full term infant is born with RV dominance. LV dominance with a trend toward RV dominance with increasing gestational age was found in preterm infants by EKG and echo criteria.

One day old infant with acyanotic congenital heart disease: critical aortic stenosis.

Congenital aortic stenosis accounts for about 5% of cardiac malformations recognized in childhood. It belongs to the category of acyanotic congenital heart disease. These lesions produce a load on the heart because of left ventricular outflow tract obstruction. Severe aortic stenosis in the newborn period (critical aortic stenosis) presents with signs of left sided heart failure (pulmonary edema, poor perfusion), right sided heart failure (hepatomegaly, peripheral edema) and may progress rapidly to total circulatory collapse. We present a case of an infant with critical aortic stenosis presenting with cyanosis, who was entirely dependent on ductal patency for systemic output. When oxygen was given, the ductus started to close, with a worsening of the left sided output and subsequent acidosis. With the right to left shunt across the ductus, the baby was cyanotic and dependent on prostaglandin to keep the ductus open. There was minimal flow across the aortic valve because of the stenosis and extremely poor left ventricular function prior to surgery. After relief of the aortic valvular obstruction, there was finally good antegrade flow across the aortic valve, terminating cyanosis.

Early cystinuria, a risk factor for metabolic urolithiasis.

The levels of urinary amino acids (cystine, amino acids with basic character, branched chain amino acids and phenylalanine) were determined in the 24 hr urines of 5,500 newborns and in 20 subjects ranging in age from 2.5 to 20 years, with a suspicion of metabolic diseases. Seven newborns have shown a biochemical pattern of cystinuria. The urinary cystine levels in the first days of life appeared to correlate with an increased risk of developing, at the adult age, metabolic mono- or bilateral urolithiasis.

The hair levels of unsaturated fatty acids (oleic, linoleic, and linolenic) indicators of the lipid metabolic balance.

The lipid metabolism was evaluated using a new method for assay of the hair contents in unsaturated fatty acids. Determinations in various hair segments and in the blood serum were performed before and after a hypolipemic diet and drug therapy in hypercholesterolemic patients in comparison with a control group. The correlation factors between the levels of the oleic, linoleic and linolenic acids in the serum and those in the hair were +0.967, +0.987 and +0.992, respectively. The method provides information on the therapy influence on the lipid metabolism variations within several weeks or months.