DiGeorge anomaly in an infant with deletion of chromosome 22 and dup(9p) due to adjacent type II disjunction.

A term white girl presented with low birth weight, minor anomalies, and congenital heart defects. The infant had microcephaly, upslanting palpebral fissures, prominent nasal bridge, short philtrum, thin upper lip vermilion, down-turned corners of the mouth, receding mandible, and short broad neck. The hands showed proximal placement of the thumbs, bilateral clinodactyly of the index finger, and bilateral transverse crease. Both hands were clenched, with the index finger overlapping the third finger and the fifth finger overlapping the fourth. There was also talipes calcaneo-valgus, bilateral dorsiflexion of the metatarsophalangeal joints, flexion of the interphalangeal joints, and hypoplasia of all nails. The patient's karyotype was 46,XX,-22, + der(9)t(9;22)(q21.13;q12.1)mat; the mother had the balanced translocation 46,XX,t(9;22)(9pter----9q21.13::22q12.1----22qter++ +;22pter---- 22q12.1::9q21.3----9qter). The infant died at age 10 days, and the autopsy showed absent thyroid isthmus and rudimentary thymus, with one small ectopic parathyroid attached to it. The lungs were hypoplastic, with abnormal lobation. The cardiac anomalies included truncus arteriosus, truncal valve stenosis, single carotid trunk, subclavian arteries arising from the distal part of the aortic arch, atrial and ventricular septal defects, right ventricular hypertrophy, and a hypoplastic left pulmonary artery. Also, multiple small accessory spleens were present in addition to a normal-sized spleen. This case combines features associated with DiGeorge anomaly and dup(9p). The chromosome abnormality in this patient appears to have arisen in a maternal germ cell due to adjacent type II disjunction.

Carotid sinus reflex function in the alloxan diabetic rabbit.

Baroreflex function was studied in three groups of adult rabbits. Seven animals were given alloxan (100-200 mg/kg) and became diabetic (group D) with mean blood sugar values of 348 +/- 30 mg/dl. Eight animals were given alloxan, but did not develop significant hyperglycemia (135 mg/dl) (group A). Nine controls (group C) were also studied (glucose, 101 mg/dl). All animals were anesthetized with pentobarbital (30 mg/kg). Blood pressure (BP) and heart rate (HR) responses to bilateral carotid occlusion (BCO) were measured before and after depressor nerve sectioning (DNx) and sinus nerve sectioning (SNx). Before sectioning, BCO caused a rise in BP of 30 +/- 4 mmHg in group C. 35 +/- 3 in group A, and 36 +/- 4 in group D. HR increased about 13 beats/min in each group. After DNx, resting BP increased in group C from 97 to 104 mmHg (P less than 0.005), but no change occurred in the other groups. Responses to BCO were significantly but similarly enhanced in all groups after DNx. HR did not increase in group D. Resting BP increased after SNx only in the controls (group C). Differences in BP elevation with BCO before and after SNx ("pure" reflex response) were identical, averaging about 35 mmHg. Thus, no alteration of BP or HR responses to BCO was identified in early alloxan diabetes. However, resting tone in the buffer nerves may have been less.

d-Transposition of the great arteries and atresia of the mitral and pulmonary valves: association with a normal anatomic left ventricle.

The clinical, angiographic, and pathologic features are presented for a case of d-transposition of the great arteries with atresia of the mitral and pulmonary valves and two well-developed ventricles. The morphologic left ventricle appeared to be functioning as a systemic ventricular aneurysm, and this may have led to the patient's death. A possible explanation for this anomaly is given.