Prenatal diagnosis of congenital adrenal hyperplasia due to 21-hydroxylase deficiency by allele-specific hybridization and Southern blot

The feasibility and accuracy of gene-specific molecular genetic diagnosis for congenital adrenal hyperplasia due to 21-hydroxylase deficiency was studied in a group of 24 pregnancies at 25% risk of carrying an affected fetus. Chorionic villus sampling was performed at 9-10 weeks' gestation. Southern analysis and polymerase chain reaction, followed by allele-specific hybridization for a panel of nine known mutations, were performed for each family. Mutations were identified in 95% of chromosomes examined; the molecular diagnosis was accurate in 96% of infants as confirmed by postnatal examination. The most common mutation identified was an A-to-G transition at base 656 in the second intron, the result of an apparent gene conversion. In one family, there had been a de novo mutation in intron 2, which was detected in the proband, but not in the mother or in the fetus. We conclude that first trimester prenatal diagnosis of congenital adrenal hyperplasia due to 21-hydroxylase deficiency is feasible and accurate employing CYP21-specific probes.

Enhancement of expression of human granulocyte-macrophage colony stimulating factor by argU gene product in Escherichia coli

Human granulocyte-macrophage colony stimulating factor (hGM-CSF) was cloned into expression vector pIN III-ompA1 and expressed in Escherichia coli JA221. When supplementation with a minor tRNA(AGA/AGG)Arg encoded by the E. coli argU gene, the expression level of hGM-CSF was raised about 3-4-fold, although there is only one rare AGG codon in hGM-CSF cDNA gene.

Clonal history of a human follicular lymphoma as revealed in the immunoglobulin variable region genes

The variable region genes used to encode the immunoglobulin expressed by tumour cells of a patient with follicular lymphoma have been identified and sequenced. Initially, a lymph node biopsy was analysed and revealed usage of VH and V kappa genes which had numerous substitutions as compared with the closest germ line genes. The pattern of mutations in VH was consistent with a role for positive selection by antigen. In addition, there was evidence in both VH and V kappa sequences for clonal heterogeneity. After 5 years, which included treatment with chemotherapy, the patient relapsed with tumour cells present in the blood. Analysis of the V-genes used by the emerging tumour revealed a single homogeneous sequence for both VH and VL, which, in each case, matched closely one of the sequences in the original lymph node biopsy. These results indicate that selection, possibly mediated by antigen, can operate on a cell destined to give rise to lymphoma, and that intraclonal variation can occur after the neoplastic event. However, in this case, late relapse in the blood is dominated by a single clone.

Properties of three proteinases functioning at G1, S and G2 phases in HeLa cells and their inhibition by guanidino- and amidino-acid esters

HeLa cells were synchronized by double thymidine-block and allowed to grow after removal of thymidine. Three proteinases, tryptase 17:17, proteinase In and late G2 proteinase, were prepared from the HeLa cells harvested at the time when each proteinase appeared in the cell cycle of the cells. All of them were suggested to be trypsin-like serine proteinases, because they hydrolyzed trypsin-specific fluorogenic substrates and their activities were inhibited by benzamidine, soybean trypsin inhibitor, leupeptin, tosyl-L-lysine chloromethan (TLCK) and diisopropylfluorophosphate (DEP). However, the actions of these proteinases on the substrates and inhibitors suggested that they were three different proteinases. They were strongly inhibited by 4-tert-butylphenyl and biphenyl esters of trans-4-guanidinomethylcyclohexanecarboxylic acid, amidinopiperidine-4-acetic and 4-propionic acids, which retard the second DNA synthetic (S) and mitotic (M) phases for 3h, 4-tert-butylphenyl ester of amidinopiperidin-4-carboxylic acid, which blocks initiation of S phase, the ester of amidinopiperidine-4-butyric acid, which suppresses the second S and M phases, and the esters of trans-4-amidinocyclohexanecarboxylic and 4-propionic acids which inhibit M phase.

Glomerular distribution of type IV collagen in diabetes by high resolution quantitative immunochemistry

We examined type IV collagen distribution and density in human diabetic kidneys by quantitative immunogold electron microscopy. We studied normal kidney transplant donors and "slow-track" and "fast-track" insulin dependent diabetic (IDDM) patients. The "slow-track" patients had IDDM for > or = 20 years and mesangial volume fraction (VvMes/glom) of < or = 0.32. The "fast-track" patients had IDDM for < or = 20 years and VvMes/glom > or = 0.37. Renal biopsies were embedded in Lowicryl, reacted with polyclonal anti-type IV collagen (in the distribution of the classical alpha 1(IV) and alpha 2(IV) collagen chains) and monoclonal anti-alpha 4(IV) collagen chain antibody followed by gold conjugated secondary antibody. We found, by morphometric techniques, a decrease in the immunogold densities of anti-type IV collagen in the subendothelial zone of the GBM in the "fast-track" IDDM patients. There was a trend towards a decrease in mesangial matrix (MM) particle density in the "fast-track" (P = 0.07) but not in the "slow-track" patients. However, because of the marked increase in MM in the "fast-track" patients, the per glomerulus estimated quantity of these antigens in MM was increased. In contrast, the density of alpha 4(IV) collagen chain was increased in the epithelial zone of the GBM in the "fast-track" IDDM patients. It is not known whether these changes in glomerular type IV collagen represent markers of advanced diabetic lesions or whether these changes might be detected earlier in diabetic patients destined for the later development of serious lesions.

Molecular genetic prenatal diagnosis of congenital adrenal hyperplasia due to 21-hydroxylase deficiency by allele-specific hybridization

The feasibility and accuracy of gene-specific molecular genetic diagnosis for congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency were studied in a group of 24 pregnancies at 25% risk of carrying an affected fetus. Chorionic villus sampling was performed in the majority of cases. Southern blot analysis was carried out to identify deletions or other gross rearrangements. In parallel, the polymerase chain reaction (PCR) was performed, followed by allele-specific oligonucleotide hybridization (ASO) for a panel of nine known mutations. Mutations were identified in 95% of the chromosomes examined. The molecular diagnosis was accurate in 23 of 24 infants. The most common mutation identified was an A-to-G transition in the second intron (52% of affected chromosomes), the result of an apparent gene conversion. One fetus carried homozygous deletion of CYP21, which accounted for 13% of all affected chromosomes. Other mutations identified included an 8-bp deletion in the third exon (22%); Ile172 to Asn, a nonconservative substitution, in the fourth exon (9%); and Gln318 to term, a nonsense mutation, in the eight exon (4%). No mutation was detected in CYP21 in 5% of obligate-affected chromosomes examined by these methods.

Differential induction of human monocyte transforming growth factor beta 1 production and its regulation by interleukin 4

We have previously shown that trauma patients' monocytes which are in vivo activated by multiple injury-induced mediators have elevated transforming growth factor-beta (TGF beta) bioactivity. Interleukin-4 (IL-4), a Th2 and B lymphocyte stimulatory factor, has been shown to inhibit monocyte production of a number of mediators both after lipopolysaccharide stimulation and after trauma-induced stimulation. However, IL-4 inhibitory effects appears to vary, depending on the mixture of inducing stimuli. Here we describe the in vitro IL-4 inhibition of human monocyte TGF beta bioactivity using several stimulation induction protocols: muramyl dipeptide stimulation alone, or after Fc gamma RI (CD64) cross-linking induction, interferon-gamma (IFN gamma) priming, or trauma-generated in vivo mediator induction. IL-4 suppressed both muramyl dipeptide-induced TGF beta bioactivity and TGF beta mRNA in a dose-dependent fashion and was most effective when IL-4 was administered at initiation of normal monocyte stimulation. Muramyl dipeptide (MDP)-induced increases in trauma patients' monocyte TGF beta bioactivity were also inhibited by high doses of IL-4 (25 ng/ml). Fc gamma RI cross-linking increased MDP-induced normal monocyte TGF beta bioactivity, but this increase could be consistently inhibited only by very high IL-4 concentrations (50 ng/ml). IL-4 did not consistently downregulate MDP-induced TGF beta bioactivity in IFN gamma-primed monocytes. IL-4 can suppress monocyte TGF beta production, as well as other monocyte mediators, but its efficiency depends on the stimuli combination present in the microenvironment.

The influence of 5'-secondary structures upon ribosome binding to mRNA during translation in yeast

The influence of 5'-secondary structure formation and 5'-leader length upon mRNA translation in yeast has been analyzed using a closely related set of cat mRNAs (Vega Laso, M. R., Zhu, D., Sagliocco, F. A., Brown, A. J. P., Tuite, M. F., and McCarthy, J. E. G. (1993) J. Biol. Chem. 268, 6453-6462). A cat mRNA with a relatively short unstructured 5'-leader (22 bases) had a ribosome loading about half that of a cat mRNA with an unstructured 5'-leader of 77 bases. The introduction of 5'-secondary structures at various positions throughout the 5'-leader of the cat mRNA inhibited translation initiation, the degree of inhibition being largely dependent upon the thermodynamic stability of the structure. Each mRNA carrying a 5'-secondary structure had a biphasic polysome distribution, indicating that the mRNA molecules were distributed between untranslated and well translated subpopulations. This suggests that once 5'-secondary structures are unwound, they reform slowly relative to the rate of translation initiation in yeast. Untranslated mRNA accumulated in 43 S preinitiation complexes, even when there were only 5 bases between the 5'-cap and the base of the hairpin. The data are consistent with the scanning hypothesis (Kozak, M. (1989) J. Cell. Biol. 108, 229-241) and suggest that 40 S ribosomal subunits bind to mRNA early in the scanning process, probably before mRNA unwinding has taken place.

Characterization of collagen-like peptides containing interruptions in the repeating Gly-X-Y sequence

Glycine is found as every third residue along the entire length of triple helices in fibrillar collagens, but the triple-helix regions of nonfibrillar collagens and other proteins usually contain one or more interruptions in this repeating pattern. A set of four peptides was designed to model the effect of interruptions in the (Gly-X-Y)n repeating pattern on triple-helix formation, stability, and folding. Into the middle of the stable triple-helical peptide (Pro-Hyp-Gly)10, an interruption was introduced representing one of the four possible categories: a glycine deletion, a deletion of a hydroxyproline (Y position), an alanine insertion, or a glycine to alanine substitution. As shown by sedimentation equilibrium, NMR, and CD studies, the introduction of an interruption still allowed formation of trimers in solution, but with marked decrease in stability. The degree of destabilization and the thermodynamic basis for the loss of stability depended on the type of interruption. The glycine substitution and alanine insertion were the least disruptive, followed by the hydroxyproline deletion, with the glycine deletion being the most destabilizing. Our results suggest that the breaks in these peptides affect both the triple-helical conformation and the monomer conformation. These studies provide a basis for considering the structural and functional consequences of different kinds of interruptions in collagen.

Alterations in the synthesis of insulin-like growth factor binding proteins and insulin-like growth factors in rat C6 glioma cells transfected with a gap junction connexin43 cDNA

When C6 glioma cells are stably transfected with a connexin43 cDNA and gap junctions are increased, the rate of cellular proliferation is decreased. To determine if this phenomenon is related to alterations in IGFBP and IGF synthesis, we have compared IGFBPs and IGFs in the conditioned media from primary rat astroglia, C6, and transfected C6 clones Cx43-13 (high expresser), and Cx43-12 and Cx43-14 (intermediate expressers). Primary astroglia produced IGFBP-2 (34 kDa) and IGFBP-3 (40-45 kDa). C6 cells synthesized high levels of IGFBP-3 and low levels of IGFBP-2, and a 24 kDa IGFBP (IGFBP-4). Cx43-13 cells did not synthesize IGFBP-3, but produced low levels of IGFBP-2 and high levels of IGFBP-4. Cx43-12 and Cx43-14 secreted IGFBP profiles similar to the parent C6 line, but with reduced levels of IGFBP-2. The lack of IGFBP-3 in Cx43-13 cells was not due to the presence of proteases. Northern analysis showed IGFBP-2 mRNA to be readily detectable only in the primary astroglia. IGFBP-3 mRNA was detected in the primary astroglia, C6, Cx43-12 and Cx43-14, but not in Cx43-13. In contrast, IGFBP-4 mRNA was readily detected only in the Cx43-13. IGF-II concentrations in the media were low to undetectable for both C6 and transfected cells. IGF-I concentrations were significantly lower in the media from transfected cells compared to the C6 cells. Stable mRNA levels for IGF-I were lower in transfected cells, with the lowest levels observed in the Cx43-13 cells. Although C6 cells did not respond mitogenically to exogenous IGF-I or IGF-II, Cx43-13 cells responded to IGF-I or IGF-II in a dose dependent manner. Conditioned media from Cx43-13 cells decreased the DNA synthesis of C6 cells, and this effect could be reversed by the addition of IGF-II. The decreased synthesis of the autocrine/paracrine growth factor IGF-I together with decreased levels of a positive modulator IGFBP-3, and the increased levels of a negative modulator IGFBP-4 in the extracellular milieu, may be responsible for the reduced proliferative capacity in cells expressing abundant connexin43.

Maize mitochondrial manganese superoxide dismutases are encoded by a differentially expressed multigene family

We have isolated maize cDNAs encoding three manganese-containing superoxide dismutases (MnSODs) distinct from the one previously reported. Molecular analyses indicate that multiple MnSOD transcripts are encoded by different, though similar, genes in the maize genome. A single MnSOD gene has been reported in all other organisms examined to date. The deduced amino acid sequences show that these maize MnSOD proteins have a mitochondrial transit peptide and that the first 9 amino acids (matrix-targeting sequence) in the transit peptide are conserved. This suggests that all the maize MnSOD proteins are mitochondria-associated isozymes. RNA blot analysis demonstrated that each member of the maize MnSOD multigene family is both spatially and developmentally regulated. One gene, Sod3.3, was predominantly expressed in the embryo late in embryogenesis. Patterns of increased Mn-SOD transcript accumulation are shown to be associated with increased mitochondrial activity during plant growth and development. The influence of mitochondrial metabolism on the expression of the nuclear MnSOD genes is discussed.

Lung endothelial dipeptidyl peptidase IV is an adhesion molecule for lung-metastatic rat breast and prostate carcinoma cells

Attachment of circulating tumor cells to endothelial cell adhesion molecules restricted to select vascular compartments is thought to be responsible for site-specific metastasis. Lung-metastatic rat R3230AC-MET breast and RPC-2 prostate carcinoma cells bound outside-out endothelial cell membrane vesicles, prepared by perfusion of the rat lung vasculature with a low-strength formaldehyde solution, in significantly higher numbers than their nonmetastatic counterparts R3230AC-LR and RPC-LR. In contrast, vesicles derived from the vasculature of a nonmetastasized organ (e.g., hind leg muscle) showed no binding preference for either of the four tumor cell lines. Lung-derived endothelial vesicles were used here to generate mAbs against lung endothelial cell adhesion molecules. The first group of mice were actively immunized against lung endothelial vesicles, whereas the second group was injected with syngeneic mouse antiserum against leg endothelial vesicles before active immunization with lung endothelial vesicles. 17 hybridoma supernatants obtained from the two fusions bound lung vesicles with at least a 10-fold higher affinity than leg vesicles. Seven (four obtained by a passive/active immunization protocol) stained rat capillary endothelia. One mAb, mAb 8.6A3, inhibited specific adhesion of lung-derived vesicles to lung-metastatic breast and prostate carcinoma cells. Purification of the antigen (endothelial cell adhesion molecule) from rat lung extracts revealed a protein with a 110-kD mol wt. NH2-terminal sequencing established identity with dipeptidyl peptidase IV which had been reported to serve as a fibronectin-binding protein. These results indicate that vesicles obtained from in situ perfused organs are a convenient immunogen for the production of antibodies to compartment-specific endothelial cell surface molecules, and reinforce the concept that endothelial cell surface components are selectively recognized by circulating cancer cells during metastasis formation.

Ultrastructural analysis of gap junctions in C6 glioma cells transfected with connexin43 cDNA

In the past, we transfected C6 glioma cells with connexin43 cDNA, resulting in a significant increase in connexin43 mRNA and protein, as well as reduced proliferation and tumorigenesis. To investigate the morphological aspects of increased connexin43 expression in these cells, we have used a combination of immunocytochemistry, cytochemistry, and electron microscopy. By confocal immunofluorescence microscopy, connexin43 protein was localized to the plasma membrane of transfected cells and extensive intracellular accumulations of connexin43 were also demonstrated. Freeze fracture preparations showed large aggregates of particles typical of mature gap junction plaques in the plasma membrane of these cells. Ultrastructural immunogold labeling with anti-connexin43 serum revealed that connexin43 protein was present in gap junctions in the plasma membrane, some of which were found in proximity to clathrin-coated pits. In addition, various intracellular membranous profiles were immunoreactive for connexin43, including annular profiles, some with fuzzy coats and some associated with lysosome-like structures. Enzyme cytochemistry revealed that these annular gap junction profiles were often associated with acid phosphatase-positive lysosomes. These studies on the intracellular localization of gap junction protein in connexin43-transfected cells are consistent with the functional expression of the transfected connexin43 cDNA and provide a useful model to study the pathways of gap junction assembly and degradation.

Inhibition of translational initiation in the yeast Saccharomyces cerevisiae as a function of the stability and position of hairpin structures in the mRNA leader

A new modular in vivo/in vitro expression system was constructed which facilitates studies of the control and regulation of gene expression in the yeast Saccharomyces cerevisiae. We studied the influence of stem-loop structures inserted into the non-translated leader region upon the steady-state levels and translation of mRNAs bearing the cat gene from the bacterial transposon Tn9. mRNA abundance changed relatively little in response to alterations in the leader sequence and structure, whereas stem-loop structures clearly inhibited translation to a degree that was dependent upon the predicted stability as well as the position of the inserted secondary structure. A stem-loop structure with a predicted stability greater than -28 kcal mol-1 and with a stem comprising at least 15 (mainly G/C) base pairs inhibited translation in vivo by at least 98%. A stem-loop structure with a predicted stability of approximately -14 kcal mol-1, whose stem comprised at least six G/C base pairs, inhibited translation in vivo by at least 66%. The hairpins were more inhibitory when placed close to the start codon than when positioned near the 5' end of the leader. An mRNA showing extensive complementarity between the leader and trailer regions was not only poorly translated but also had a steady-state level at least three times higher than the average for all the cat constructs examined. Translation of the various mRNAs in a yeast cell-free system followed qualitatively the same pattern as the results obtained in vivo. The stem-loop structures were far less inhibitory in a reticulocyte lysate system. Overall, the data are likely to reflect the full spectrum of translational activities of yeast mRNAs in vivo determined by secondary structure and emphasize the importance of translation as a control step in gene expression.

Insulin-like growth factor binding protein-4 gene expression is induced by transfection of gap junction connexin43 gene in a C6 glioma cell line

When C6 glioma cells are stably transfected with a connexin43 cDNA and the gene overexpressed, the rate of cellular proliferation is decreased. To determine if this phenomenon is related to alterations in IGFBP synthesis, we have compared the conditioned media of primary rat astroglia, C6, clones Cx43-13 (high expresser of the transfected connexin43 gene), and Cx43-12 and Cx43-14 (intermediate expressers). Primary astroglia produced IGFBP-2 (M(r) 34 K) and IGFBP-3 (40-45 K). C6 cells synthesized high levels of IGFBP-3 and low levels of IGFBP-2, and a 24 K IGFBP (IGFBP-4). Cx43-13 cells did not synthesize IGFBP-3, but produced low levels of IGFBP-2 and high levels of IGFBP-4. Cx43-12 and Cx43-14 secreted IGFBP profiles similar to the parent C6 line, but with reduced levels of IGFBP-2. Northern analysis showed the changes in IGFBPs in the conditioned media to be correlated with alterations in stable mRNA levels. IGFBP-4, a inhibitor of IGF biological action, was produced in greater quantities by the slowly proliferating Cx43-13 cells. Alterations in IGFBP-4 synthesis may be responsible, at least in part, for the reduced proliferative capacity in cells with abundant connexin43.

Correlation between the lung distribution patterns of Lu-ECAM-1 and melanoma experimental metastases

Lu-ECAM-1 is a 90-kDa lectin-like, melanoma-cell-binding endothelial-cell adhesion molecule that mediates colonization of the lungs by B16-F10 melanoma cells. The well-known formation of pleural and sub-pleural B16-F10 melanoma colonies is correlated quantitatively with prominent histochemical staining of endothelia of pleural capillaries and sub-pleural venules with anti-Lu-ECAM-1 MAb 6D3. The less frequent endothelial staining of perivenous and peribronchial venules is associated with fewer B16-F10 colonies in these locations, and the occasional segmental staining of pulmonary veins coincides with rare tumor nodules which usually expand in an asymmetric fashion around these veins. Lu-ECAM-1 is also expressed on endothelia of some tumor vessels, indicating that these vessels are recruited from the same host blood vessels that originally caused the arrest of blood-borne B16-F10 melanoma cells. The close association between the lung distribution patterns of Lu-ECAM-1-positive blood vessels and experimental melanoma metastases is further evidence of the importance of endothelial-cell adhesion molecules in the formation of metastases.

The left ventricle affects the duration of right ventricular ejection

OBJECTIVE

The aim was to determine if rapid changes in left ventricular pressure can acutely alter right ventricular systolic pressure and thus influence the length of right ventricular ejection.

METHODS

The experiments were performed in six open chest anaesthetised dogs, weight 18-25.5 kg. Left and right ventricular pressures and pulmonary blood flow were recorded continuously as left ventricular pressure was abruptly decreased by opening a shunt in systole. From these data, the pressure and flow changes and the duration of right ventricular ejection were determined.

RESULTS

Opening the left ventricular shunt caused left ventricular pressure to fall from 94.1(SD 10.5) to 62.6(11.3) mm Hg (p < 0.01), right ventricular pressure to fall from 30.3(4.6) to 27.0(3.6) mm Hg (p < 0.01), and pulmonary flow to fall from 69.5(14.2) to 57.5(13.9) ml.s-1. The duration of right ventricular ejection, determined from pulmonary flow, also decreased from 192.7(22.7) to 157.2(18.7) ms (p < 0.05) and was significantly related to the length of left ventricular systole. Time between end diastole and peak negative dP/dt decreased for both left and right ventricle. Left and right ventricular time intervals were related before (r = 0.99) and after (r = 0.75) opening the shunt.

CONCLUSIONS

The duration of right ventricular ejection was decreased by a sudden decrease in left ventricular afterload and was significantly related to the length of left ventricular systole. The duration of right ventricular ejection may be coupled with left ventricular contraction through ventricular interdependence.

Molecular genetic analysis in autosomal dominant keratoconus

Members in three generations of a family whose propositus had keratoconus were examined by biomicroscopy, with a corneoscope and a computer-assisted videophoto-keratoscope. Keratoconus was detected in eight of 15 family members with vertical transmission consistent with autosomal dominant inheritance. Affected individuals displayed variable topographic features. Abortive "nipple-type" cones were identified in some individuals in successive generations using the computer-assisted videophotokeratoscope and more advanced nipple-type cones detected on biomicroscopy of other family members. We selected a COL6A1 cDNA (the gene encoding the alpha 1 chain of type VI collagen) as a "candidate gene" to determine cosegregation with the disease locus. Linkage analysis excluded a gene locus for keratoconus on the most telomeric region of chromosome 21 in this family.

Detection of IgE antibodies specific for 1-phenyl-2,3-dimethyl-3-pyrazoline-5-one by RAST: a serological diagnostic method for sensitivity to pyrazoline drugs

Certain adverse reactions to pyrazoline drugs resemble IgE-mediated hypersensitivity. However, convincing evidence of antigen-antibody interactions is not fully demonstrated. In this study, IgE antibodies specific for 1-phenyl-2,3-dimethyl-3-pyrazoline-5-one have been found in 17 out of 19 serum samples from individuals sensitive to pyrazoline drugs with 4-aminoantipyrine discs by Radio Allergo Sorbent Test (RAST). In contrast, we have not found any positive results from 10 normal donors without sensitivity to pyrazoline drugs after ingestion of metamizol 500 mg/day for 14 days. Therefore, our results provide further evidence in favor of an IgE-dependent mechanism in patients suffering from sensitivity to pyrazoline drugs. The determination of specific IgE antibodies could be used as a serodiagnostics method.

Growth retardation in glioma cells cocultured with cells overexpressing a gap junction protein

To examine the role of gap-junctional intercellular communication in controlling cell proliferation, we have transfected C6 glioma cells with connexin 43 cDNA. The growth of transfected clones was dramatically reduced compared with nontransfected glioma cells. To further characterize the role of gap junctions in controlling proliferation, we have examined the growth of C6 cells cocultured with transfected cells overexpressing connexin 43. Although C6 cells grew at their normal rate when cocultured with nontransfected C6 cells, when cocultured with connexin 43-overexpressing cells they displayed a dramatic reduction in growth rate. Furthermore, a significant, dose-dependent reduction in cell proliferation was noted when C6 cells were cultured in medium conditioned by transfected cells. This effect correlated with the level of connexin 43 expression. These results suggest that the decreased cell proliferation rate of transfected cells and C6 cells cultured with them is due to the secretion of a growth inhibitory factor(s) and that the secretion of this factor may be linked to the level of gap junctional intercellular communication.

Expression of the maize MnSod (Sod3) gene in MnSOD-deficient yeast rescues the mutant yeast under oxidative stress

Superoxide dismutases (SOD) are ubiquitous in aerobic organisms and are believed to play a significant role in protecting cells against the toxic, often lethal, effect of oxygen free radicals. However, direct evidence that SOD does in fact participate in such a protective role is scant. The MnSOD-deficient yeast strain (Sod2d) offered an opportunity to test the functional role of one of several SOD isozymes from the higher plant maize in hopes of establishing a functional bioassay for other SODs. Herein, we present evidence that MnSOD functions to protect cells from oxidative stress and that this function is conserved between species. The maize Sod3 gene was introduced into the yeast strain Sod2d where it was properly expressed and its product processed into the yeast mitochondrial matrix and assembled into the functional homotetramer. Most significantly, expression of the maize Sod3 transgene in yeast rendered the transformed yeast cells resistant to paraquat-induced oxidative stress by complementing the MnSOD deficiency. Furthermore, analyses with various deletion mutants of the maize SOD-3 transit peptide in the MnSOD-deficient yeast strain indicate that the initial portion (about 8 amino acids) of the maize transit peptide is required to direct the protein into the yeast mitochondrial matrix in vivo to function properly. These findings indicate that the functional role of maize MnSOD is conserved and dependent on its proper subcellular location in the mitochondria of a heterologous system.

In vivo growth of C6 glioma cells transfected with connexin43 cDNA

In order to examine the possible role of intercellular communication via gap junctions in the control of tumor growth, we have transfected C6 glioma cells with connexin43 cDNA. We obtained several clones with variable expression of connexin43. The growth rate of these clones in culture was inversely related to the degree of expression of the transfected cDNA. To examine the growth of these transfected cells in vivo, cells were grown in spinner culture flasks to form spheroids 250-300 microns in diameter. Spheroids of nontransfected C6 cells produced large gliomas. Immunohistochemical and in situ hybridization analyses revealed relatively high levels of connexin43 protein and mRNA in the host tissue, while little of this protein was detected in the glioma. In contrast, spheroids of connexin43-transfected cells grew more slowly and exhibited elevated levels of connexin43 protein and mRNA. These findings suggest that the expression of connexin43 may be associated with the control of brain tumor growth in vivo.

Disease expression and molecular genotype in congenital adrenal hyperplasia due to 21-hydroxylase deficiency

Genotyping for 10 mutations in the CYP21 gene was performed in 88 families with congenital adrenal hyperplasia due to 21-hydroxylase deficiency. Southern blot analysis was used to detect CYP21 deletions or large gene conversions, and allele-specific hybridizations were performed with DNA amplified by the polymerase chain reaction to detect smaller mutations. Mutations were detected on 95% of chromosomes examined. The most common mutations were an A----G change in the second intron affecting pre-mRNA splicing (26%), large deletions (21%), Ile-172----Asn (16%), and Val-281----Leu (11%). Patients were classified into three mutation groups based on degree of predicted enzymatic compromise. Mutation groups were correlated with clinical diagnosis and specific measures of in vivo 21-hydroxylase activity, such as 17-hydroxyprogesterone, aldosterone, and sodium balance. Mutation group A (no enzymatic activity) consisted principally of salt-wasting (severely affected) patients, group B (2% activity) of simple virilizing patients, and group C (10-20% activity) of nonclassic (mildly affected) patients, but each group contained patients with phenotypes either more or less severe than predicted. These data suggest that most but not all of the phenotypic variability in 21-hydroxylase deficiency results from allelic variation in CYP21. Accurate prenatal diagnosis should be possible in most cases using the described strategy.

Canine bone shape analysis by use of a radiographic image-classification system

A radiographic image-classification system was developed to analyze and compare the shape of the humerus of neonatal Labrador Retriever and Labrador Retriever x Beagle pups that were either phenotypically normal or affected with an ocular-skeletal dysplasia syndrome. The system consistently defined the shape of the humerus within the groups of pups studied and indicated a difference in the shape of the humerus between normal and affected pups. Results indicated that the radiographic image-classification system may be able to identify Labrador Retriever pups affected by the ocular-skeletal dysplasia syndrome at or shortly after birth.

Intercellular calcium signaling via gap junctions in glioma cells

Calcium signaling in C6 glioma cells in culture was examined with digital fluorescence video microscopy. C6 cells express low levels of the gap junction protein connexin43 and have correspondingly weak gap junctional communication as evidenced by dye coupling (Naus, C. C. G., J. F. Bechberger, S. Caveney, and J. X. Wilson. 1991. Neurosci. Lett. 126:33-36). Transfection of C6 cells with the cDNA encoding connexin43 resulted in clones with increased expression of connexin43 mRNA and protein and increased dye coupling, as well as markedly reduced rates of proliferation (Zhu, D., S. Caveney, G. M. Kidder, and C. C. Naus. 1991. Proc. Natl. Acad. Sci. USA. 88:1883-1887; Naus, C. C. G., D. Zhu, S. Todd, and G. M. Kidder. 1992. Cell Mol. Neurobiol. 12:163-175). Mechanical stimulation of a single cell in a culture of non-transfected C6 cells induced a wave of increased intracellular calcium concentration ([Ca2+]i) that showed little or no communication to adjacent cells. By contrast, mechanical stimulation of a single cell in cultures of C6 clones expressing transfected connexin43 cDNA induced a Ca2+ wave that was communicated to multiple surrounding cells, and the extent of communication was proportional to the level of expression of the connexin43 cDNA. These results provide direct evidence that intercellular Ca2+ signaling occurs via gap junctions. Ca2+ signaling through gap junctions may provide a means for the coordinated regulation of cellular function, including cell growth and differentiation.

The presence of specific IgE to salicyloyl and O-methylsalicyloyl in aspirin-sensitive patients

Certain adverse reactions to aspirin (ASA), nonsteroidal anti-inflammatory drugs (NSAIDs) and pyrazoline derivatives resemble IgE-mediated hypersensitivity. However, convincing evidence of antigen-antibody interactions or of the inhibition of the cyclooxygenase pathway of arachidonic acid metabolism leading to an increase in the generation of leukotrienes (LTs) and a decrease in the generation of prostaglandins (PGs) was not fully demonstrated. In this study, two types of specific IgE antibodies have been found in 27 serum samples from 28 ASA-sensitive patients with salicyloyl-discs and O-methylsalicyloyl-discs by Radio Allergo Sorbent Tests (RAST). The positive rates were 96.4% and 71.4%, respectively. In contrast, no positive results could be found in 10 normal donors without ASA sensitivity after ingestion of ASA 500 mg/day for 14 days. Further investigation of the chemical structure of epitopes was done by cross inhibition studies. Our results are an increasing evidence in favour of an IgE-dependent mechanism in patients suffering from ASA sensitivity. Hopefully, the determination of specific IgE antibodies will be a safe diagnostic method of ASA sensitivity in vitro.

Blocking of lung endothelial cell adhesion molecule-1 (Lu-ECAM-1) inhibits murine melanoma lung metastasis

The 90-kD lung endothelial cell adhesion molecule-1 (Lu-ECAM-1) selectively promotes Ca(2+)-dependent adhesion of lung-metastatic B16 melanoma cells. Corresponding with their metastatic performance, high lung-metastatic B16-F10 melanoma cells bind in significantly higher numbers to Lu-ECAM-1 than their intermediate and low lung-metastatic counterparts B16-L8-F10 and B16-F0, respectively. Maximum attachment is observed at a density of approximately 2.4 x 10(2) Lu-ECAM-1 sites/microns2 of plastic surface. B16 melanoma cell binding to Lu-ECAM-1 is blocked by mAb 6D3 and is competitively inhibited by soluble Lu-ECAM-1. C57B1/6 mice passively immunized with anti-Lu-ECAM-1 mAb 6D3 or actively immunized with purified Lu-ECAM-1 exhibit an anti-Lu-ECAM-1 antibody titer-dependent reduction in the number of B16 experimental metastases. Lu-ECAM-1 promotes neither binding nor metastasis of other lung-metastatic tumor cells (e.g., KLN205). Our data indicate that an "antiadhesion" therapy directed at interfering with the adherence of blood-borne tumor cells to organ-specific vascular endothelium is efficient in the control of metastasis formation in selective organ sites.

Renal structure and function in insulin-dependent diabetes mellitus in man

PURPOSE

To review renal pathological changes in diabetes, which include thickening of all renal extracellular basement membranes and the mesangial matrix and, to a lesser extent, mesangial cell expansion.

CRITICAL RENAL LESIONS IN DIABETIC NEPHROPATHY

Two renal lesions appear critical in diabetic nephropathy. Mesangial expansion out of proportion to the size of the glomerulus is inversely related to proteinuria, hypertension and a declining glomerular filtration rate. Arteriolar hyalinosis is related to global glomerulosclerosis and both are correlated with the clinical features of nephropathy. By the time renal dysfunction is clinically detectable, these lesions tend to be advanced. Interstitial volume may be increased in insulin-dependent diabetes mellitus, particularly in areas containing sclerotic glomeruli or marked tubular atrophy.

FUTURE RESEARCH

Longitudinal studies of renal structure and function and a simultaneous study of potential risk factors and pathways of injury are necessary to develop more refined predictors and clearer pathogenic concepts of this important diabetic complication.

The evolution of two west African populations

The identification of genetically coherent populations is essential for understanding human evolution. Among the culturally uniform ethnic groups of west Africa, there are two geographically distinct populations with high frequencies of sickle-cell hemoglobin (HbS). Although the HbS mutation in each group is found on distinguishable chromosomes 11, these populations have been assumed to be parts of a single population. Analysis of mitochondrial DNA (mtDNA) in these populations demonstrated that the two populations identified by alternative chromosomes 11 bearing HbS have distinct distributions of mitochondrial genotypes, i.e., they are maternally separate. These studies also showed that, contrary to expectation, the mtDNA of some individuals is heteroplasmic. For nuclear loci, a comparison of the frequency of alternative alleles established that these populations are genetically distinct. Both the mitochondrial and nuclear data indicate that these populations have been separate for approximately 50,000 years. Although HbS in the two populations is usually attributed to recent, independent mutations, the duration of the separation and the observed geographic distribution of the population allow for the possibility of an ancient origin of HbS. Assuming an ancient mutation and considering the known biogeography, we suggest that HbS protected selected populations from malaria in rain forest refuges during the most recent ice age.

Characteristics of C6 glioma cells overexpressing a gap junction protein

1. C6 glioma cells transfected with connexin43 cDNA display a dramatic increase in the level of connexin43 mRNA and protein. 2. This overexpression of connexin43 is evident at the cellular level, as revealed with in situ hybridization and immunocytochemistry. Transfection with connexin43 cDNA also induced actin stress fibers in these glioma cells. 3. Although we observed up to a 50-fold increase in the level of connexin43 mRNA following transfection, virtually all of this mRNA was present in the polysomal fraction. 4. Overexpression of connexin43 mRNA did not appear to compete with other cellular mRNAs for access to the translational machinery. 5. It is likely that the reduced proliferation rate of the transfected cells, reported earlier, is due to enhanced connexin43 expression and intercellular coupling.

Clinical, biochemical, and neuropsychiatric evaluation of a patient with a contiguous gene syndrome due to a microdeletion Xp11.3 including the Norrie disease locus and monoamine oxidase (MAOA and MAOB) genes

Norrie disease is a rare X-linked recessive disorder characterized by blindness from infancy. The gene for Norrie disease has been localized to Xp11.3. More recently, the genes for monoamine oxidase (MAOA, MAOB) have been mapped to the same region. This study evaluates the clinical, biochemical, and neuropsychiatric data in an affected male and 2 obligate heterozygote females from a single family with a submicroscopic deletion involving Norrie disease and MAO genes. The propositus was a profoundly retarded, blind male; he also had neurologic abnormalities including myoclonus and stereotopy-habit disorder. Both obligate carrier females had a normal IQ. The propositus' mother met diagnostic criteria for "chronic hypomania and schizotypal features." The propositus' MAO activity was undetectable and the female heterozygotes had reduced levels comparable to patients receiving MAO inhibiting antidepressants. MAO substrate and metabolite abnormalities were found in the propositus' plasma and CSF. This study indicates that subtle biochemical and possibly neuropsychiatric abnormalities may be detected in some heterozygotes with the microdeletion in Xp11.3 due to loss of the gene product for the MAO genes; this deletion can also explain some of the complex phenotype of this contiguous gene syndrome in the propositus.

Comparative significance in systolic ventricular interaction

STUDY OBJECTIVE

The aim was to measure the systolic coupling between the ventricles and to determine the relative importance of ventricular interaction in the pressure development of each ventricle.

DESIGN

Acute studies were done in dogs to measure the changes in right and left ventricular pressures (dPr, dPl) caused by sudden changes in left ventricular pressure (dPl') with release of an aortic constriction, and sudden changes in right ventricular pressure (dPr') with release of a pulmonary artery constriction, respectively. The instantaneous cross talk gain [dPr/dPl' (Klr) or dPl/dPr' (Krl)] was calculated during the ejection phase. The potential systolic pressure generated by the contralateral ventricle was evaluated as the cross talk gain multiplied by the contralateral systolic developed pressure.

EXPERIMENTAL MATERIAL

Studies were done in eight random source dogs (12-18 kg), anaesthetised with sodium pentobarbitone.

MEASUREMENTS AND MAIN RESULTS

The maximal Klr was lower than the maximal Krl, at 0.09 (SD 0.05) v 0.25 (0.06), and the mean Klr also was lower than the mean Krl, at 0.04 (0.02) v 0.10 (0.03), p less than 0.05. The potential right ventricular pressures developed by the left ventricle [maximum 10.3(5.6), mean 4.8(2.7) mm Hg] were not significantly different from the potential left ventricular pressures developed by the right ventricle [maximum 8.8(2.7), mean 3.4(0.7) mm Hg]. However, the ratio between the potential transmitted pressure and the measured developed pressure was greater in the right ventricle [maximum 39.0(21.1), mean 17.8(8.9)%] than in the left ventricle [maximum 11.1(7.1)%, p less than 0.05; mean 3.9(1.5)%, p less than 0.01]. This suggests that about 20-40% of the right ventricular systolic pressure may result from the left ventricle and about 4-10% of the left ventricular systolic pressure may result from right ventricle.

CONCLUSIONS

Although the pressure coupling was greater in right to left ventricular interaction, right ventricular pressure generation may be more dependent on the left ventricle. Systolic ventricular interaction may be more important for right ventricular systolic function. Further, the parameters of right ventricular systolic function currently used may be considerably affected by the left ventricle.

[Effects of liuwei dihuang decoction and its compositions on blood sugar and glycogen in mice]

We have studied the effects of liuwei dihuang decoction (LDD) and its compositions on blood sugar and glycogen in mice, and found that sanbu, shanzhuyu-danpi and shanyao-fuling matched pairs can reduce the level of blood sugar, while LDD, sanbu, shudi-zexie and shanzhuyu-danpi matched pairs can increase the content of glycogen in liver. The present study is only a preliminary research on the effects of LDD and its compositions on the metabolism of sugar in the body.

Fluid resuscitation with deferoxamine prevents systemic burn-induced oxidant injury

We studied the effect of deferoxamine (DFO) infused after burns on hemodynamic stability as well as local and systemic inflammation and oxidant-induced lipid peroxidation. Eighteen anesthetized sheep were given a 40% of total body surface burn and fluid resuscitated to restore oxygen delivery (DO2) and filling pressures to baseline values. Animals were resuscitated with lactated Ringer's (LR) alone or LR plus 1,500 ml of a 5% hetastarch complexed with DFO (8 mg/ml). Animals were killed 6 hours postburn. The sheep resuscitated with LR and LR plus hetastarch demonstrated significant lung inflammation and significant increases in lung and liver malondialdehyde (MDA) from controls of 47 +/- 6 and 110 +/- 7 nMol/gm to 63 +/- 13 and 202 +/- 59 for LR and 67 +/- 4 and 211 +/- 9 for LR + hetastarch, respectively. The group resuscitated with hetastarch alone required 15% less fluid. VO2 returned to baseline values in both groups by 2 hours. Resuscitation with the 5% hetastarch-DFO decreased total fluids by 30% over LR and prevented the increase in lung and liver MDA. In addition, postburn VO2 increased by 25% above baseline values. Burn tissue edema, measured as protein-rich lymph flow, was significantly increased with the administration of DFO compared with the other groups. We conclude that DFO used for burn resuscitation prevents systemic lipid peroxidation and decreases the vascular leak in nonburn tissues while also increasing O2 utilization. Resuscitation with hetastarch-DFO may accentuate burn tissue edema, possibly by increased perfusion of burn tissue.

Transfection of C6 glioma cells with connexin 43 cDNA: analysis of expression, intercellular coupling, and cell proliferation

C6 glioma cells express low levels of the gap junction protein connexin 43 and its mRNA and display very weak dye coupling. When implanted into the rat cerebrum, these cells quickly give rise to a large glioma. To investigate the role of gap junctions in the tumor characteristics of these cells, we have used Lipofectin-mediated transfection to introduce a full-length cDNA encoding connexin 43. Several transfected clones were obtained that exhibited various amounts of connexin 43 mRNA transcribed from the inserted cDNA. Immunocytochemical analysis revealed an increase in the amount of connexin 43 immunoreactivity in the transfected cells, being localized at areas of intercellular contact as well as in the cytoplasm. The level of dye coupling was also assessed and found to correlate with the amount of connexin 43 mRNA. When cell proliferation was followed over several days, cells expressing the transfected cDNA grew more slowly than non-transfected cells. These transfected cells will be useful in examining the role of gap junctions in tumorigenesis.

Changes in catalase activity in lung and liver after endotoxemia in sheep

Endotoxemia in the sheep produces oxidant-induced cardiopulmonary dysfunction and lung and liver lipid peroxidation, which can be prevented with exogenous catalase, indicating a role for hydrogen peroxide. We determined whether endotoxin-induced oxidant release altered endogenous catalase activity to help explain the lipid peroxidation. Unanesthetized sheep were given 2 micrograms/kg Escherichia coli endotoxin and killed at 5 hr or 24 hr. Lung and liver lipid peroxidation, measured as malondialdehyde, and catalase activity were determined after endotoxin and compared with controls. Lung tissue MDA increased by 100% at 5 hr and was still elevated by 50% at 24 hr, while catalase activity decreased by 50% at 5 hr and remained decreased, suggesting irreversible inactivation. Liver MDA was also doubled at both 5 and 24 hr, but catalase activity remained unchanged. We conclude that endotoxemia results in a significant inactivation of endogenous catalase activity in lung, but not in liver. The lung may be more prone to a subsequent H2O2 injury before restoration of catalase activity.

Assignment of the Nance-Horan syndrome to the distal short arm of the X chromosome

There are three types of X-linked cataracts recorded in Mendelian Inheritance in Man (McKusick 1988): congenital total, with posterior sutural opacities in heterozygotes; congenital, with microcornea or slight microphthalmia; and the cataract-dental syndrome or Nance-Horan (NH) syndrome. To identify a DNA marker close to the gene responsible for the NH syndrome, linkage analysis on 36 members in a three-generation pedigree including seven affected males and nine carrier females was performed using 31 DNA markers. A LOD score of 1.662 at theta = 0.16 was obtained with probe 782 from locus DXS85 on Xp22.2-p22.3. Negative LOD scores were found at six loci on the short arm, one distal to DXS85, five proximal, and six probes spanning the long arm were highly negative. These results make the assignment of the locus for NH to the distal end of the short arm of the X chromosome likely.

Effect of endotoxin and a burn injury on lung and liver lipid peroxidation and catalase activity

Both endotoxin and a burn alone produce oxidant-induced tissue lipid peroxidation. The endotoxin response is due in large part to hydrogen peroxide. The combination of endotoxin after a burn results in an increased liver, but not lung, oxidant injury. Our purpose was to determine whether the burn oxidant injury inactivated endogenous liver tissue catalase, thereby amplifying a subsequent H2O2 insult. Twenty-six adult sheep were studied. Twelve sheep had a 15% TBS burn. Tissue catalase activity, measured in lung and liver 3 days postburn, was significantly decreased from a control of 3.58 +/- 1.8 and 193 +/- 63, respectively, to 1.72 +/- 0.63 and 148 +/- 33 k(sec-1)/0.5 gram tissue. The addition of endotoxin 3 days postburn resulted in an increase in liver malondialdehyde, MDA, a measure of lipid peroxidation, from a control of 110 +/- 80 to 450 +/- 54 nmol/gram tissue. This value was significantly greater than the 210 +/- 80 nmol/gram tissue seen after endotoxin alone. Lung tissue MDA with burn and endotoxin was 65 +/- 8 compared to 42 +/- 7 for control and 80 +/- 6 nmol/gram for endotoxin alone. We conclude that a decrease in liver catalase activity occurs after a burn. The decrease corresponds to an accentuated oxidant-induced lipid peroxidation after an added endotoxin insult where H2O2 is known to be an etiologic agent. The catalase activity also decreases in postburn lung, but accentuated lung damage was not seen, indicating a variable tissue response from the burn-induced decrease in antioxidant activity.(ABSTRACT TRUNCATED AT 250 WORDS)

[An evaluation of the China-made HIV antibody test reagents]

This paper reports the results of the evaluation of the China-made HIV antibody screening test reagents, including the IF and IE reagents prepared by the Institute of Virology, CAPM, the ELISA reagent prepared by the Shanghai Institute of Biological Products. Based on the results, the sensitivities of the IF and IE are from 91.2% to 96.9%; the specificities, from 94.6% to 97.3%. Due to the low HIV prevalence in China, the predictive values of negative of these reagents are up to 100%; but the predictive values of positive are very low. It is suggested that these reagents can be used for HIV antibody screen testing in China. The package of some reagents should be improved, the price of some reagents should be decreased.

Induction of tumor necrosis factor by macrophage colony-stimulating factor in vivo

The effect of human urinary colony-stimulating factor (CSF-1) on the production of tumor necrosis factor (TNF) in vivo was assessed. Purified CSF-1 was administered i.v. to rabbits 4 days prior to injection with lipopolysaccharide (LPS). TNF in the serum prepared from rabbits bled 90 min after LPS injection was measured using cytotoxicity assays employing mouse L929 cells and antirabbit TNF monoclonal antibody. The results indicated that CSF-1 was able to induce the production of TNF in vivo and had a synergistic effect with Propionibacterium acnes.

Intestinal immunity to Trichinella spiralis is a property of OX8- OX22- T-helper cells that are generated in the intestine

The phenotype of T-helper cells conferring protection against Trichinella spiralis (Ts) was studied using adoptive transfer procedures and T-helper cell subsets isolated by monoclonal antibodies. With these techniques OX8- OX22+ and OX8- OX22- T-helper cell populations were isolated from thoracic duct lymph (TDL) of infected rats three-five-fold more concentrated than in unfractionated lymph. The OX8- OX22- cell subset alone transferred enhanced rejection of adult worms from the intestine. The origin of protective OX8- OX22- cells was examined in mesenteric lymphadenectomized (MX) rats. After MX, protective cells were found in the cell population draining directly from the intestine on Days 2-3 after infection. Protective cells first appeared in the mesenteric lymph node (MLN) and efferent lymph at Day 3. MX rats rejected T. spiralis at the same time as intact controls and showed enhanced rejection when immune TDL were transfused. No evidence was found for a direct role of the MLN in the generation or expression of parasite rejection. Depletion of migrating OX8- OX22- blast cells by 48-hr drainage of TDL did not influence the expression of an anamnestic response to challenge infection. This suggests that an intestinally resident cell population has a substantial role in mediating primary worm rejection and anamnestic immunity. Day 2 OX8- OX22- cells from MX rats proliferated in response to the presentation of adult and muscle larvae antigens in vitro. We conclude that protection resides in the OX8- OX22- T-helper cell subset that is produced and functions in the intestine.

Early pulmonary and hemodynamic effects of a chest wall burn (effect of ibuprofen)

The cardiopulmonary effects of a third-degree scald burn involving the anterolateral chest wall was compared with a burn of equal size (30% of total body surface) to the flanks in anesthetized sheep with lung lymph fistulas. The chest-burn group was characterized by immediate decreases in cardiac output (6.5 to 3.0 L/min), central venous pressure (5 mm Hg to 0 mm Hg), pulmonary wedge pressure (10 mm Hg to 6 mm Hg), and urine output 1.5 ml/kg/hr to less than 0.5 ml/kg/hr. The temperature of pulmonary artery blood increased from 38 to 42 degrees C and plasma prostacyclin increased from 20 to 200 pg/ml. These changes were significantly different from those seen in the body sheep with burns. Initial fluid requirements necessary to restore filling pressures were 50% greater in the sheep with chest burns than in the sheep with body burns. An early decrease in static lung compliance was also seen after chest burn that was not the result of increased lung edema. A progressive decrease in compliance, urine output, and stroke output was also seen in the later postburn period (6 to 7 hours), which was significantly improved by a chest wall escharotomy. Postmortem analysis in the chest-burn group revealed a significantly increased malondialdehyde content, a reflection of increased oxygen radical-induced lipid peroxidation relative to the body burn. Pretreatment of the chest burn with ibuprofen, 12.5 mg/kg, prevented the initial vasodilator and lung compliance changes so that early cardiopulmonary status was identical to that seen with a body burn alone. Ibuprofen also decreased the lung tissue malondialdehyde content. We conclude that a burn involving the chest wall results in cardiopulmonary abnormalities, not seen after a body burn of a comparable size, which appear to be due to hyperthermia and an increased release of prostacyclin and O2 radicals.