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Premortem diagnosis of the DiGeorge syndrome and its partial variants relies on the demonstration of a primary defect in cell-mediated immunity, generally in the setting of an infant with congenital heart disease, hypocalcemia, absence of a thymic shadow, and typical dysmorphic features. Although T-cell enumeration is considered a vital part of the diagnostic evaluation, no studies to date have addressed the issue of appropriate reference data in infants with congenital heart disease. We therefore undertook a prospective descriptive study of lymphocyte phenotype analysis in 27 nontransfused infants undergoing diagnostic cardiac catheterization. Striking differences were seen between patients and adult controls in means percentages and numbers of most lymphocyte subsets analyzed. Few differences were found in comparing the patient data to values for age-matched control infants without heart disease. The data are discussed with reference to published values for patients with partial DiGeorge syndrome. It is concluded that lymphocyte phenotype analysis in the diagnostic evaluation of patients with suspected DiGeorge syndrome must utilize appropriate reference values.

Rat hepatocyte nuclei were electrostatically sorted and collected from specific regions of the cell cycle. Proteins were extracted from homogeneous populations of nuclei with cetyltrimethylammonium bromide and chromatographed by one- and two-dimensional acid-urea polyacrylamide gel electrophoresis. Small quantitative differences were observed in amido black stained two-dimensional patterns of the nuclear proteins of the G0 + G1 and G2 + M populations. However, comparison of the two-dimensional autoradiographs of 3H-leucine labeled nuclear proteins in these populations revealed dramatic differences. After isoproterenol administration, animals showed enhanced labeling of certain nuclear proteins in G2 + M populations, but no noticeable effect in protein labeling was observed in the G0 + G1 populations. Four days after the administration of isoproterenol, fluorescent histograms exhibited increased amounts of DNA in the G2 + M populations. Comparison of the total amino acid composition of two proteins from control animals revealed the distinct chemical contrast of these proteins. Both proteins possessed higher ratios of acidic to basic residues than anticipated for basic proteins. These procedures and findings should prove useful for further understanding of mechanisms of toxicant effects upon nuclear protein metabolism.

The high resolution proton magnetic resonance spectral properties of three C57BL/6J mouse cell populations (EL4 ascites tumor cells, normal spleen leukocytes, and normal erythrocytes) were investigated. Packed cell pellets were investigated at 100 MHz and 13.56 MHz. The 100-MHz spectra contained identifiable non-water proton resonances as well as the water resonance. The major non-water resonances from the EL 4 cells and normal leukocytes resembled resonances from lipid extracts, whereas the non-water resonances from erythrocytes resembled resonances from hemoglobin solutions. The reciprocals of the water proton spin-lattice relaxation times were roughly proportional to the total sample water content at both 100 and 13.56 MHz. The estimated slopes of these plots were frequency-dependent. The water proton relaxation rate generally increased with increasing total protein content of the packed cell pellets.

Three general patterns of segmental coordination (i.e., sequential [SEQ], simultaneous [SIM], and modified simultaneous [MSIM]) have been hypothesized for jumping. The purposes of this study were to describe the pattern of segmental coordination used in vertical jumping and to determine if skilled jumpers displayed distinguishing patterns of coordination. Maximum vertical jumps were performed in the counter movement (CMJ) and static jump (SJ) conditions by a heterogeneous group of 20 lean, adult subjects (AS). Smoothed, digitized film records provided the data for four segments: head-arms-trunk, trunk, thighs, and shanks. For each segment the phase of positive contribution was considered to begin with initiation of extension and end with maximum angular velocity. Bisegmental and multisegmental variables were defined to assess the extent of simultaneity. Skill was determined by the effective integration of the legs (ratio of peak upward velocity of CMJ and SJ) and by the use of stored elastic energy. Although 13 AS had MSIM patterns, the amount of flexion was small (less than or equal to 1 degree) so these AS were reclassified. With multisegmental analyses the number of AS with SIM patterns ranged from 13 to 17; about half the time was SIM. Using bisegmental analyses all 20 AS had SIM patterns; about three-fourths of the time was SIM. Skilled AS initiated extension and reached maximum velocity of the segments in proximal to distal order and with very small delays between adjacent segments.

Tumor-specific immunoprophylaxis was achieved in C57BL/6J mice against EL 4 leukosis cell challenge by sensitization of the syngeneic host with multiple ip injections of irradiated EL 4 cells. A minimal radiation dose was used to replication-block EL 4 cells before inoculation, as defined by dose-response analysis of irradiated EL 4 cells. Multiple ip injections of irradiated EL 4 cells stimulated development of significant, yet relatively low, levels of cytotoxic lymphoid activity (CLA) in lymphoid cells of the peritoneal exudate as measured by in vitro 51Cr-release cytotoxicity assays. The specific temporal and frequency dependencies of the inoculation regimen for achieving immunoprophylaxis indicated that, in addition to CLA, other, short-lived, immune processes were important in the tumor rejection. These observations showed the capacity of the C57BL/6J host for tumor-specific immune recognition and rejection of the syngeneic EL 4 leukemia. The tumor rejection could be elicited solely by inoculations of irradiated EL 4 cells and did not require exogenous amplifiers, such as immunoadjuvants, chemical modifiers, and/or allogeneic immune information transfer.

The diagnostic evaluation of infants with suspected DiGeorge syndrome includes peripheral blood lymphocyte phenotype analysis by flow cytometry. Mononuclear cells are typically concentrated from infants' blood samples by Ficoll-Hypaque (FH) density gradient centrifugation prior to monoclonal antibody (Mab) staining. Having observed that lymphocyte percentages in samples prepared by this technique were low more often than anticipated based on the prevalence of the suspected diagnosis, we undertook a prospective study of 55 infants with congenital heart disease comparing FH with a whole-blood (WB) technique. Sixty healthy adult controls were similarly studied. We report the observation that FH-prepared mononuclear cells from blood samples of infants less than 4 months of age yield substantially different phenotypes than WB-prepared samples. The differences are related to red blood cell (RBC) contamination. No such difference was seen with adult samples. Unlike FH-prepared adult samples, contaminating RBCs are indistinguishable from lymphocytes through at least 4 months of age when assessed by the standard cytometric gating parameters of forward and 90 degrees light scatter. The use of a WB ammonium chloride lysis technique is recommended as most appropriate for the preparation of infants' blood samples.