Biomedical subjects

E J Neufeld

Publications and source records attributed to E J Neufeld.

At least 37 records · Page 2Linked to original sources

PubMed1998

Refined mapping of the gene for thiamine-responsive megaloblastic anemia syndrome and evidence for genetic homogeneity.

Thiamine-responsive megaloblastic anemia (TRMA, also known as Rogers syndrome, OMIM 249270) is a rare autosomal recessive disorder characterized by a triad of megaloblastic anemia, diabetes mellitus, and sensorineural deafness. Patients respond, to varying degrees, to treatment with megadoses of thiamine. We have recently shown genetic linkage of the TRMA gene to a 16-centimorgan (cM) region on 1q23.2-1q23.3 based on the analysis of four large, inbred families of Alaskan, Italian, and Israeli-Arab origin. Here we narrow the TRMA interval down to 4 cM based on genetic recombination, homozygosity mapping, and linkage disequilibrium (highest LOD score of 12.5 at D1S2799, at a recombination fraction of 0). We provide further evidence that the TRMA gene is located in this region and confirm the homogeneity of the disease. In this analysis, we genotyped seven additional families of diverse ethnic origin (Pakistani, Indian, Italian, Brazilian, and Japanese), and analyzed additional markers in two previously reported families showing evidence of linkage disequilibrium in a large area of their haplotypes. The multi-system manifestations of TRMA suggest that thiamine has a pivotal role in a multiplicity of physiological processes. Mapping the TRMA gene and understanding the molecular basis of the disease might, thus, shed light on the role of thiamine in common disorders such as deafness, anemia, and diabetes.

Anemia, Megaloblastic↗

PubMed1998

Combined schedule of 7-valent pneumococcal conjugate vaccine followed by 23-valent pneumococcal vaccine in children and young adults with sickle cell disease.

We compared the immunogenicity of 7-valent pneumococcal-conjugate vaccine plus 23-valent pneumococcal vaccine to immunization with 23-valent vaccine only in individuals > or = 2 years of age with sickle cell disease. IgG pneumococcal antibody concentrations were higher in the combined schedule group with no increase in side effects observed after immunization with 23-valent vaccine.

Adolescent↗

PubMed1998

Update on genetic risk factors for thrombosis and atherosclerotic vascular disease.

The strong familial occurrence of venous and arterial thromboembolic disease has prompted ongoing research to identify novel risk factors. Polymorphisms in the factor VII and prothrombin genes are related to increased thrombosis, but the mechanism of increased risk remains to be elucidated. Elevated levels of plasma homocysteine and of the variant lipoprotein(a) particle also contribute to increased thrombotic risk, due in part to polymorphisms in the apolipoprotein(a) gene and the gene for methylene tetrahydrofolate reductase.

Arteriosclerosis↗

PubMed1998

Hemophilia. A new approach to an old disease.

The history of hemophilia diagnosis and therapy has been a turbulent one. We are coming full circle, back to the use of genetics as the main diagnostic tool for this disease. Therapeutically, the retroviruses that ravaged one generation of hemophiliac patients now may participate in the cure for the next generation. The hemophilia community hopes that the future of hemophilia care will follow a course guided by this modified quote from James Russell Lowell: "New times demand new measures, and men [and women]. As the world advances and in time outgrows the laws that in our fathers' [and mothers'] days were the best, doubtless after us some purer scheme will be shaped out by wiser man [and women] than we, made wiser by the steady growth of truth."

Blood Transfusion↗

PubMed1997

Soluble adhesion molecules in infants and children undergoing cardiopulmonary bypass.

BACKGROUND: The vascular injury and tissue damage after cardiopulmonary bypass (CPB) involves leukocyte-endothelial interactions mediated by cell adhesion molecules. This study was designed to determine the time course of soluble adhesion molecule levels after CPB in infants and children and to determine whether these levels correlated with preoperative variables, intraoperative bypass management, or postoperative course. METHODS AND RESULTS: In 56 patients undergoing CPB (median age 1.0 year, range 2 days to 19 years), plasma concentrations of soluble E-, P-, and L-selection, soluble ICAM-1, and soluble VCAM-1 were measured using sandwich enzyme-linked immunosorbent assays at the following times: at induction of anesthesia, after 15 minutes of CPB, at the end of CPB, and 1, 6, 18, and 42 hours after CPB. Preoperative, intraoperative, and postoperative data were prospectively recorded. All soluble adhesion molecule levels fell markedly at the initiation of CPB as a result of a combination of dilution and bypass circuit uptake. The time course of soluble selectins (P, E, and L), normalized to end of bypass levels, all rose significantly (P<.001) in the initial 6 hours after CPB and then returned to end bypass levels at 42 hours. Soluble ICAM-1 and VCAM rose 63% and 89% in the first 6 hours and remained elevated throughout the 42 hours. Peak soluble P-selectin levels were associated with total support time (P=.04) and preoperative cyanosis (P=.003). Soluble L-selectin levels were inversely associated with longer total support time (P=.002), longer circulatory arrest time (P=.004), longer length of intubation (P=.0009), preoperative cyanosis (P=.002), and younger age at surgery (P=.01). CONCLUSIONS: Soluble adhesion molecules have a characteristic time course in infants and children undergoing CPB. The soluble adhesion molecule levels after CPB change most significantly in patients with the highest potential for vascular injury: younger, cyanotic patients with longer pump times and longer postoperative courses. These data may be useful in the assessment of new therapies.

Adolescent↗

PubMed1997

CCAAT displacement protein (CDP/cut) recognizes a silencer element within the lactoferrin gene promoter.

Expression of neutrophil secondary granule protein (SGP) genes is coordinately regulated at the transcriptional level, and is disrupted in specific granule deficiency and leukemia. We analyzed the regulation of SGP gene expression by luciferase reporter gene assays using the lactoferrin (LF) promoter. Reporter plasmids were transiently transfected into non-LF-expressing hematopoietic cell lines. Luciferase activity was detected from reporter plasmids containing base-pair (bp) -387 to bp -726 of the LF promoter, but not in a -916-bp plasmid. Transfection of a -916-bp plasmid into a LF-expressing cell line resulted in abrogation of the silencing effect. Sequence analysis of this region revealed three eight-bp repetitive elements, the deletion of which restored wild-type levels of luciferase activity to the -916-bp reporter plasmid. Electrophoretic mobility shift assay and UV cross-linking analysis identified a protein of approximately 180 kD that binds to this region in non-LF-expressing cells but not in LF-expressing cells. This protein was identified to be the CCAAT displacement protein (CDP/cut). CDP/cut has been shown to downregulate expression of gp91-phox, a gene expressed relatively early in the myeloid lineage. Our observations suggest that the binding of CDP/cut to the LF silencer element serves to suppress basal promoter activity of the LF gene in non-LF-expressing cells. Furthermore, overexpression of CDP/cut in cultured myeloid stem cells blocks LF expression upon granulocyte colony-stimulating factor-induced neutrophil maturation without blocking phenotypic maturation. This block in LF expression may be due, in part, to the persistence of CDP/cut binding to the LF silencer element.

Base Sequence↗

PubMed1997

CASP, a novel, highly conserved alternative-splicing product of the CDP/cut/cux gene, lacks cut-repeat and homeo DNA-binding domains, and interacts with full-length CDP in vitro.

Human CDP/cut and its murine counterpart, cux1/CDP are homeodomain repressor proteins in the family of Drosophila Cut. Northern blot analysis reveals complex alternative splicing, including forms too small to encode the full 1505 amino acid protein. We have characterized a CDP/cut alternatively spliced cDNA (CASP) of 3.4 kb. Human CASP, a predicted 678 amino acid polypeptide, shares 400 amino acids with CDP, but has an alternate N terminal exon of 20 aa, and the C-terminal 258 amino acids diverge from CDP/cut entirely. As the unique C-terminus of CASP lacks the three 'cut-repeats' and homeodomain of CDP/cut, we predict it does not bind DNA. Murine CASP, 96% similar to human, shares these features. Database searches identify homologs in chicken (86% identical to human CASP) and yeast (29% identical to human). Murine CASP mRNA is ubiquitous in mouse tissues and in tissue-culture cell lines. We generated a specific antiserum against the unique C-terminus of CASP, and used this reagent to demonstrate that CASP protein is expressed as an approx. 80 kDa protein in human and murine cells. Co-translation of in vitro-translated CDP and CASP mRNA, followed by immunoprecipitation with specific anti-CASP IgG, shows that CASP polypeptide can from a complex with CDP. Studies of the intron/exon structure of the murine cux/CDP/mCASP locus (>> 100 kb) reveal that the unique 3' exons of CASP are interposed between cut-repeats 2 and 3 of the cux gene. We speculate that a primordial CASP-like gene captured a cut-repeat-homeobox gene to give rise to the eukaryotic Cut/CDP family of proteins.

Alternative Splicing↗

PubMed1997

Passive cigarette smoking and reduced HDL cholesterol levels in children with high-risk lipid profiles.

BACKGROUND: HDL cholesterol levels are known to be lower in smokers than in nonsmokers. Previous studies have demonstrated an association of decreased HDL cholesterol with passive smoking in children but have not adjusted for potential confounding factors. METHODS AND RESULTS: In a cross-sectional, pilot-scale study, we examined the relationship of HDL cholesterol levels to passive smoking in children and adolescents referred to a tertiary hyperlipidemia clinic. Eligibility criteria included (1) first visit to a lipid clinic, (2) LDL cholesterol >95th percentile for age or HDL cholesterol <5th percentile, (3) age between 2 and 18 years, and (4) absence of secondary causes of hyperlipidemia. Sociodemographic information, diet record, medical history, and fasting lipid profiles were obtained. Of 109 eligible patients, 103 (94%) were studied. Twenty-seven percent came from households with cigarette smokers. HDL cholesterol levels were 38.7+/-1.2 mg/dL (mean+/-SEM) in passive smokers versus 43.6+/-1.2 mg/dL in children without smoke exposure (P=.005). Smoking exposure was not significantly associated with other lipid values. The effect of smoking on HDL cholesterol was minimally affected by potential confounders. In multivariate regression adjusting for body mass index, age, sex, exercise, and dietary fat intake, passive smoking remained a significant risk factor for decreased HDL cholesterol (P=.012). CONCLUSIONS: Mean HDL cholesterol levels are lower in dyslipidemic children from households with smokers than in those without household smoke exposure. Passive smoking may worsen the risk profile for later atherosclerosis among high-risk young persons.

Child↗

PubMed1997

Asparaginase-associated lipid abnormalities in children with acute lymphoblastic leukemia.

To further elucidate the incidence and potential mechanism of asparaginase-associated lipid abnormalities in children with acute lymphoblastic leukemia (ALL), we serially obtained fasting lipid and lipoprotein studies on 38 of the 43 consecutively diagnosed children with ALL before, during, and after asparaginase therapy. We also evaluated a second population of 30 long-term survivors of childhood ALL; a fasting lipid and lipoprotein profile was obtained once at study entry. The mean peak triglyceride level during asparaginase of 465 mg/dL (standard deviation [SD] 492) was significantly higher (P = .003) than the level of 108 mg/dL (SD 46) before the initiation of asparaginase therapy. Sixty-seven percent of the newly diagnosed patients had fasting triglyceride levels greater than 200 mg/dL during asparaginase therapy; 15 patients (42%) had levels greater than 400 mg/ dL, 7 with levels greater than 1,000 mg/dL. The incidence of hypertriglyceridemia did not vary by type of asparaginase or risk status of ALL (defined by white blood cell count and age). None of the 7 patients with triglyceride levels greater than 1,000 mg/dL developed pancreatitis. In contrast, 4 of the 13 patients without triglyceride elevation developed pancreatitis; 3 of the 4 patients had fasting studies at the height of their abdominal pain. Nuclear magnetic resonance analysis of lipid subclasses showed a significant increase in the smaller, denser forms of very low density lipoprotein (VLDL) and negligible chylomicron fraction in a subset of patients with marked triglyceride elevation. Lipoprotein lipase activity was consistently above normative values for all levels of triglyceride and could not be explained by obesity or hyperglycemia. Apolipoprotein B(100) levels increased during asparaginase therapy, although the mechanism of this remains unclear. LDL reciprocally decreased with increased VLDL during asparaginase therapy. After asparaginase therapy, triglyceride levels (mean, 73 mg/dL [SD 33]) were significantly lower than levels obtained during asparaginase therapy. Triglyceride levels for survivors did not differ from the normal range or postasparaginase levels in the newly diagnosed patients. These data show a striking temporal association between asparaginase therapy and hypertriglyceridemia. Changes in cholesterol, in contrast, were not temporally related to asparaginase treatment. Cholesterol levels were elevated (>200 mg/dL) in 20% of the patients after asparaginase, which may be due to continued treatment with corticosteroids. The mean cholesterol level of long-term survivors of 177 mg/dL was significantly higher than the norm (P = .045). High-density lipoprotein (HDL) levels were significantly lower than normal at all time periods and for both populations; 25% of survivors had HDL levels less than 35 mg/dL. We conclude that modifications in asparaginase therapy are not necessary. In cases of triglyceride elevation greater than 2,000 mg/dL when the risk of pancreatitis is increased, close clinical monitoring is imperative. Larger studies are needed to determine the incidence of dyslipidemia in long-term survivors of ALL as well as the relationship between lipid abnormalities and other late effects of treatment, notably obesity and cardiomyopathies.

Adolescent↗

PubMed1997

Localization of the gene for thiamine-responsive megaloblastic anemia syndrome, on the long arm of chromosome 1, by homozygosity mapping.

Thiamine-responsive megaloblastic anemia, also known as "TRMA" or "Rogers syndrome," is an early-onset autosomal recessive disorder defined by the occurrence of megaloblastic anemia, diabetes mellitus, and sensorineural deafness, responding in varying degrees to thiamine treatment. On the basis of a linkage analysis of affected families of Alaskan and of Italian origin, we found, using homozygosity mapping, that the TRMA-syndrome gene maps to a region on chromosome 1q23.2-23.3 (maximum LOD score of 3.7 for D1S1679). By use of additional consanguineous kindreds of Israeli-Arab origin, the putative disease-gene interval also has been confirmed and narrowed, suggesting genetic homogeneity. Linkage analysis generated the highest combined LOD-score value, 8.1 at a recombination fraction of 0, with marker D1S2799. Haplotype analysis and recombination events narrowed the TRMA locus to a 16-cM region between markers D1S194 and D1S2786. Several heterozygote parents had diabetes mellitus, deafness, or megaloblastic anemia, which raised the possibility that mutations at this locus predispose carriers in general to these manifestations. Characterization of the metabolic defect of TRMA may shed light on the role of thiamine deficiency in such common diseases.

Alaska↗

PubMed1997

Induction of aquaporin-1 mRNA following cardiopulmonary bypass and reperfusion.

BACKGROUND: Cardiopulmonary bypass (CPB) and hypothermic circulatory arrest (HCA) are important components of congenital cardiac surgery. Ischemia/reperfusion injury and inflammatory cascade activation result in endothelial damage and vascular leak which are clinically manifested as pulmonary edema and low cardiac output postoperatively. Newborns are particularly susceptible. Subtraction cloning is a useful method of isolating induced genes and can be applied to CPB/HCA. MATERIALS AND METHODS: We used a newborn lamb model replicating infant CPB with HCA to obtain tissues during various periods of reperfusion. We utilized subtraction cloning to identify mRNA induced in lung following CPB/HCA and reperfusion. Ribonuclease protection was used to quantify mRNA levels. RESULTS: We isolated a cDNA encoding ovine aquaporin-1 in a subtracted cDNA screen comparing control lung with lung exposed to CPB/HCA and reperfusion. Aquaporin-1 mRNA levels increased 3-fold in lung (p = .006) exposed to CPB/HCA and 6 hr of reperfusion. No induction was observed immediately following bypass or after 3 hr of reperfusion. We found no significant induction of aquaporin-1 mRNA following bypass, arrest, and reperfusion in other tissues surveyed, including ventricle, atrium, skeletal muscle, kidney, brain, and liver. CONCLUSIONS: Our finding that aquaporin-1 mRNA is reproducibly induced in lung following CPB/HCA with 6 hr of reperfusion suggests an important role for the water channel in the setting of pulmonary edema. Induction of Aquaporin-1 is late compared with other inflammatory mediators (ICAM-1, E-selectin, IL-8). Further studies are needed to determine if aquaporin-1 contributes to the disease process or if it is part of the recovery phase.

Amino Acid Sequence↗

PubMed1996

CDP/cut is the DNA-binding subunit of histone gene transcription factor HiNF-D: a mechanism for gene regulation at the G1/S phase cell cycle transition point independent of transcription factor E2F.

Transcription of the genes for the human histone proteins H4, H3, H2A, H2B, and H1 is activated at the G1/S phase transition of the cell cycle. We have previously shown that the promoter complex HiNF-D, which interacts with cell cycle control elements in multiple histone genes, contains the key cell cycle factors cyclin A, CDC2, and a retinoblastoma (pRB) protein-related protein. However, an intrinsic DNA-binding subunit for HiNF-D was not identified. Many genes that are up-regulated at the G1/S phase boundary are controlled by E2F, a transcription factor that associates with cyclin-, cyclin-dependent kinase-, and pRB-related proteins. Using gel-shift immunoassays, DNase I protection, and oligonucleotide competition analyses, we show that the homeodomain protein CDP/cut, not E2F, is the DNA-binding subunit of the HiNF-D complex. The HiNF-D (CDP/cut) complex with the H4 promoter is immunoreactive with antibodies against CDP/cut and pRB but not p107, whereas the CDP/cut complex with a nonhistone promoter (gp91-phox) reacts only with CDP and p107 antibodies. Thus, CDP/cut complexes at different gene promoters can associate with distinct pRB-related proteins. Transient coexpression assays show that CDP/cut modulates H4 promoter activity via the HiNF-D-binding site. Hence, DNA replication-dependent histone H4 genes are regulated by an E2F-independent mechanism involving a complex of CDP/cut with cyclin A/CDC2/ RB-related proteins.

Base Sequence↗

PubMed1996

Hypoxia enhances stimulus-dependent induction of E-selectin on aortic endothelial cells.

In many diseases, tissue hypoxia occurs in conjunction with other inflammatory processes. Since previous studies have demonstrated a role for leukocytes in ischemia/reperfusion injury, we hypothesized that endothelial hypoxia may "superinduce" expression of an important leukocyte adhesion molecule, E-selectin (ELAM-1, CD62E). Bovine aortic endothelial monolayers were exposed to hypoxia in the presence or absence of tumor-necrosis factor alpha (TNF-alpha) or lipopolysaccharide (LPS). Cell surface E-selectin was quantitated by whole cell ELISA or by immunoprecipitation using polyclonal anti-E-selectin sera. Endothelial mRNA levels were assessed using ribonuclease protection assays. Hypoxia alone did not induce endothelial E-selectin expression. However, enhanced induction of E-selectin was observed with the combination of hypoxia and TNF-alpha (270% increase over normoxia and TNF-alpha) or hypoxia and LPS (190% increase over normoxia and LPS). These studies revealed that a mechanism for such enhancement may be hypoxia-elicited decrements in endothelial intracellular levels of cAMP (<50% compared with normoxia). Addition of forskolin and isobutyl-methyl-xanthine during hypoxia resulted in reversal of cAMP decreases and a loss of enhanced E-selectin surface expression with the combination of TNF-alpha and hypoxia. We conclude that endothelial hypoxia may provide a novel signal for superinduction of E-selectin during states of inflammation.

1-Methyl-3-isobutylxanthine↗

PubMed1996

ARMS test for diagnosis of factor VLeiden mutation, a common cause of inherited thrombotic tendency.

We developed a simple and rapid amplification-refractory mutation system (ARMS) assay for the factor V mutation [R506Q] (factor VLeiden), which results in the autosomal dominant thrombotic tendency, resistance to activated protein C (rAPC). PCR primers within Exon 10 of the factor V gene were designed. A common upstream primer was paired with either a mutant or wild-type-specific downstream primer. The 3'-most nucleotide of the specific primers recognized either the mutant or normal allele, and the 3' penultimate nucleotide was mismatched to enhance specificity of the reaction. The assay was validated using authentic factor VLeiden DNA samples. Seven of 103 hematologically normal children (6.8%) were found to be heterozygotes. Among 27 patients studied by the rAPC assay, ARMS assay and rAPC results were concordant in 26. Among these were a 1-year-old child with a calcified clot in the inferior vena cava. Both the patient and his father were heterozygous for the mutation and both had abnormal rAPC assays. rAPC and factor VLeiden assays were discordant in a young girl with a history of stroke. Biochemical rAPC assay was abnormal, while ARMS assay revealed amplification only with wild-type primers, suggesting a non-[R506Q] mechanism for rAPC. This assay will be a valuable tool for studying subjects with thromboses and their family members.

DNA Primers↗

PubMed1996

Blockade of selectin-mediated leukocyte adhesion improves postischemic function in lamb hearts.

BACKGROUND: Leukocyte-endothelial interactions appear to have a important role in ischemia/reperfusion injury and are mediated by specific leukocyte and endothelial adhesion molecules. The selectins are adhesion molecules found on leukocytes (L-selectin) and endothelium (P and E selectin) that bind to oligosaccharide ligands containing fucose and sialic acid to mediate leukocyte rolling on the endothelium. Fucoidin is a nontoxic sulfated fucose oligosaccharide derived from seaweed that blocks the selectins. METHODS: We tested the effects of fucoidin in an isolated blood-perfused neonatal (age range, 3 to 7 days; mean age, 4.3 days) lamb heart model undergoing 2 hours of cold cardioplegic ischemia. In group F (n = 8) fucoidin (30 mg/L) was added at initial reperfusion. Group C (n = 9) received only cardioplegia with no reperfusion intervention. Isovolumic maximum developed pressure and the maximum positive and negative first derivatives of pressure were measured using a catheter-tip transducer in an intraventricular balloon before ischemia and at 30 minutes of reperfusion. Coronary blood flow, myocardial oxygen consumption, and white blood cell counts in the circulating blood were also measured. RESULTS: Percent recoveries of baseline maximum developed pressure and maximum positive and negative first derivatives of pressure in group F (86% +/- 5%, 81% +/- 10%, and 74% +/- 8%, respectively; mean +/- standard deviation) were higher than in group C (77% +/- 5%, 70% +/- 9%, and 65% +/- 6%; p < 0.05). Group F postischemic coronary blood flow was greater (190% +/- 35%) than in group C (102% +/- 10%; p < 0.05). Recovery of myocardial oxygen consumption in group F (86% +/- 14%) was greater than group C (72% +/- 11%; p < 0.05). Postischemic white blood cell count in group F (88% +/- 4%) was greater than in group C (81% +/- 5%; p < 0.05). CONCLUSIONS: Selectin blockade with fucoidin resulted in better recovery of left ventricular function, coronary blood flow, and myocardial oxygen consumption after cold ischemia, despite a higher circulating white blood cell count. These data support the hypothesis that endothelial-leukocyte interactions play an important role in ischemia/reperfusion and suggest that selectin blockade may be a useful therapeutic strategy.

Animals↗

PubMed1996

Analytical performance and clinical utility of a direct LDL-cholesterol assay in a hyperlipidemic pediatric population.

This study compares a new latex immunoseparation method for the direct determination of plasma low-density lipoprotein cholesterol (LDL-C) with the reference procedure for LDL-C (beta-quantification) in a pediatric hyperlipidemic population. The direct LDL-C assay has a mean bias of -98 mg/L in a fasting group (n = 96) of patients (mean triglycerides 1057 +/- 720 mg/L) and a bias of +177 mg/L in a nonfasting group (n = 42, mean triglycerides 4854 +/- 5457 mg/L). The mean total analytical error calculated from our data is 13.8%. The direct LDL-C assay and the commonly used Friedewald calculation respectively classified 81% and 84% of fasting patients correctly, according to the cutoffs of 1100 and 1300 mg/L for LDL-C set by the National Cholesterol Education Program for pediatric patients. Of combined fasting and nonfasting patients, 80% were correctly classified by the direct LDL-C assay. Therefore, despite several analytical shortcomings, the direct LDL-C assay may be useful in managing hyperlipidemic children without the need for a fasting specimen.

Adolescent↗

PubMed1995

Induction of interleukin-8 messenger RNA in heart and skeletal muscle during pediatric cardiopulmonary bypass.

BACKGROUND: Interleukin-8 (IL-8), the major neutrophil chemoattractant factor, contributes to inflammatory tissue injury by activating neutrophils and promoting their migration into tissue. IL-8 levels increase in serum of patients undergoing cardiopulmonary bypass (CPB). The purpose of this study was to determine if IL-8 gene expression is activated in tissues subjected to CPB with or without hypothermic arrest. METHODS AND RESULTS: IL-8 transcript levels were measured by ribonuclease protection in samples of human atrium and skeletal muscle from children before and after CPB for repair of congenital heart defects. Results were quantified by PhosphorImager. Atrial IL-8 mRNA levels increased during CPB in 14 of 16 patients tested (median increase, 2.9-fold; P = .0029). In skeletal muscle, IL-8 mRNA increased in 11 of 12 patients (median, 12-fold; P = .012). Degree of IL-8 induction in atrium and muscle was not directly associated with total support time or cross-clamp time. Transcript increase in skeletal muscle occurred with or without a period of circulatory arrest, suggesting that the stimulus of CPB alone was sufficient to induce message production. Baseline values for IL-8 mRNA varied widely among patients in atrium and skeletal muscle. In situ hybridization analysis revealed diffuse increase in IL-8 mRNA throughout the tissue after CPB, with striking increase in some small veins. CONCLUSIONS: We conclude that production of IL-8 mRNA occurs in most patients during CPB in both myocardium and skeletal muscle. This may result in high local IL-8 concentrations, contributing to the tissue injury after CPB.

Cardiopulmonary Bypass↗

PubMed1995

Repressor activity of CCAAT displacement protein in HL-60 myeloid leukemia cells.

CCAAT displacement protein (CDP)/cut is implicated in several systems as a transcriptional repressor of developmentally regulated genes. In myeloid leukemia cells, CDP/cut binding activity as assayed on the promoter of the phagocyte-specific cytochrome heavy chain gene gp91-phox varies inversely with expression of gp91-phox mRNA. We used two approaches to ascertain whether CDP/cut serves as a repressor of gp91-phox gene expression. First, we used transient transfection assays in 3T3 cells to demonstrate that the CDP/cut binding site from the gp91-phox promoter acts as a negative regulatory element in artificial promoter constructs. Second, we isolated a stable transformant of HL-60 myeloid cells constitutively expressing transfected CDP/cut cDNA. Stable transformants carrying expression vector alone or expressing CDP/cut mRNA were induced to differentiate along the macrophage lineage with phorbol ester or along the neutrophil lineage with dimethyl sulfoxide or retinoic acid/dimethylformamide. Northern blot analysis was used to assess induction of mRNAs encoding gp91-phox, and the myeloid oxidase cytosolic components, p47 and p67. In the stable transformant expressing transfected CDP/cut cDNA, gp91-phox induction was selectively reduced, whereas morphologic differentiation and induction of mRNA for myeloid oxidase components p47 and p67 were unaffected. These data provide persuasive evidence that CDP/cut acts to repress the gp91-phox gene.

3T3 Cells↗