Meta-analysis of trials comparing beta-blockers, calcium antagonists, and nitrates for stable angina

CONTEXT

Which drug is most effective as a first-line treatment for stable angina is not known.

OBJECTIVE

To compare the relative efficacy and tolerability of treatment with beta-blockers, calcium antagonists, and long-acting nitrates for patients who have stable angina.

DATA SOURCES

We identified English-language studies published between 1966 and 1997 by searching the MEDLINE and EMBASE databases and reviewing the bibliographies of identified articles to locate additional relevant studies.

STUDY SELECTION

Randomized or crossover studies comparing antianginal drugs from 2 or 3 different classes (beta-blockers, calcium antagonists, and long-acting nitrates) lasting at least 1 week were reviewed. Studies were selected if they reported at least 1 of the following outcomes: cardiac death, myocardial infarction, study withdrawal due to adverse events, angina frequency, nitroglycerin use, or exercise duration. Ninety (63%) of 143 identified studies met the inclusion criteria.

DATA EXTRACTION

Two independent reviewers extracted data from selected articles, settling any differences by consensus. Outcome data were extracted a third time by 1 of the investigators. We combined results using odds ratios (ORs) for discrete data and mean differences for continuous data. Studies of calcium antagonists were grouped by duration and type of drug (nifedipine vs nonnifedipine).

DATA SYNTHESIS

Rates of cardiac death and myocardial infarction were not significantly different for treatment with beta-blockers vs calcium antagonists (OR, 0.97; 95% confidence interval [CI], 0.67-1.38; P = .79). There were 0.31 (95% CI, 0.00-0.62; P = .05) fewer episodes of angina per week with beta-blockers than with calcium antagonists. beta-Blockers were discontinued because of adverse events less often than were calcium antagonists (OR, 0.72; 95% CI, 0.60-0.86; P<.001). The differences between beta-blockers and calcium antagonists were most striking for nifedipine (OR for adverse events with beta-blockers vs nifedipine, 0.60; 95% CI, 0.47-0.77). Too few trials compared nitrates with calcium antagonists or beta-blockers to draw firm conclusions about relative efficacy.

CONCLUSIONS

beta-Blockers provide similar clinical outcomes and are associated with fewer adverse events than calcium antagonists in randomized trials of patients who have stable angina.

Monophosphoryl lipid A (MPL) upregulates major histocompatibility complex (MHC) class I expression by increasing interferon-gamma (IFN-gamma)

Tumor immunity is primarily mediated by cells as CD8+ cytotoxic T lymphocytes (CTL) recognize tumor antigen by MHC class I molecules. But most tumors are associated with a decreased expression of MHC class I to escape the antitumor immunity of the host. Our previous data have demonstrated that MPL has an antitumor effect on metastatic lung cancer of B16 melanoma with enhancing cytotoxicity due to increase of IFN-gamma and IL-2, and decrease of IL-4, which indicates the stimulation of type 1 helper T cells (Th1). To determine the effects of MPL, IFN-gamma, TNF-alpha, and IL-1 alpha on MHC class I expression of B16 melanoma cells, we evaluated the expression of MHC class I molecules with treatments of MPL, IFN-gamma, TNF-alpha, and IL-1 alpha by flow cytometry. The supernatant of MPL-treated spleen cells in vitro upregulated the expression of MHC class I molecules of B16 melanoma cells compared to the control supernatant of spleen cells. The MHC class I expression of B16 melanoma cells treated with IFN-gamma, but not TNF-alpha or IL-1 alpha, increased in a time-dependent manner. In conclusion, MPL upregulated MHC class I expression of B16 melanoma cells by activating spleen cells via IFN-gamma. These data suggest that increased IFN-gamma by MPL is responsible for the upregulation of MHC class I expression to augment cytotoxicity. Therefore, we suggest that MPL could play an important role in immunotherapy.

Epidemiology of eating disordered symptoms in the Korean general population using a Korean version of the Eating Attitudes Test

OBJECTIVE

The purposes of the present study were to estimate the proportion of subjects with a high score on the Korean version of Eating Attitudes Test--26 (KEAT-26), which may provide preliminary data regarding the prevalence rate of eating disorders in the Korean general population, and to further examine the sociocultural hypothesis of eating disorders.

METHOD

Using a multi-stage questionnaire sampling method, we surveyed 3062 subjects (1249 males, 1813 females) from 3896 Korean adults in a nationwide area.

RESULTS

8.5% (260/3062) of subjects scored above the cut-off on the KEAT-26. Their demographic correlates, eating traits, and other characteristics relating to general psychopathology were similar to those of patients with eating disorders and female Caucasian controls in Western countries.

DISCUSSION

These results suggest that changes in various sociocultural aspects have increased the risk of developing eating disorders in Korea, and support the sociocultural hypothesis of eating disorders.

Mutations affecting ligand specificity of the G-protein-coupled receptor for the Saccharomyces cerevisiae tridecapeptide pheromone

Random mutations were generated in the G-protein-coupled receptor (Ste2p) for the tridecapeptide pheromone (alpha-factor) of Saccharomyces cerevisiae. These mutants were screened for variants that responded to antagonists. Because multiple mutations were detected in each mutant receptor recovered from the screen, site-directed mutagenesis was used to create single-site mutant receptors. Three receptors containing mutations F55V, S219P, and S259P were analyzed for their biological responses to various alpha-factor analogs and for their ligand binding profiles. Cells expressing each of the mutant receptors responded to alpha-factor as well as or better than wild-type cells in a growth arrest assay. In contrast, the binding of alpha-factor to the F55V and S219P mutant receptors was at least 10-fold reduced in comparison to wild-type receptor indicating a complex non-linear correlation between binding affinity and biological activity. Cells expressing mutant receptors responded to some normally inactive analogs in biological assays, despite the fact that these analogs had a low affinity for Ste2p. The analysis of these mutant receptors confirms previous findings that the first and sixth transmembrane regions of Ste2p are important for ligand interaction, ligand specificity, and/or receptor activation to initiate the signal transduction pathway. Changes in binding affinity of pheromone analogs to wild-type and mutant receptors indicate that residue 55 of Ste2p is involved with both ligand binding and signal transduction.

Urinary 5-aminolevulinic acid (ALA) adjusted by creatinine: a surrogate for plasma ALA?

5-Aminolevulinic acid (ALA) is the first intermediate substrate in the heme synthetic pathway and is the substrate of aminolevulinic acid dehydratase (ALAD, porphobilinogen synthase). Because lead effectively inhibits ALAD activity, resulting in accumulation of ALA in urine and blood, urinary ALA (ALAU) has been used as a biomarker for lead exposure or early biologic effect of lead. Intraindividual variation in urinary excretion of ALA requires the use of 24-hour urine samples or adjustment of single urine samples by other normalizing variables, such as urinary creatinine concentration. Previous studies of ALAU concentration have used various adjustment methods; however, few have compared creatinine-adjusted ALAU concentration with ALA concentration in plasma (ALAP) from subjects with low (< 30 micrograms/dL) to moderate (< 60 micrograms/dL) levels of blood lead. To determine if creatinine-adjusted ALAU is associated with ALAP, we measured ALAU, ALAP, and urinary creatinine in 65 Korean lead workers with blood lead concentrations in the range of 14-60 micrograms/dL. ALAU, ALAU/creatinine, or ALAU/log creatinine all correlated with ALAP. However, ALAU/creatinine correlated more closely with ALAP based on Spearman's r (rs = 0.40, P, = 0.0009), supporting the use of ALA/creatinine in single urine samples as a surrogate for ALAP.

Experimental hypercholesterolemia induces ultrastructural changes in the elastic laminae of rabbit aortic valve

Atherosclerosis is the most severe problem in the high-pressure systemic circulation and similar changes also occur in the high-pressure loading valve. This study was designed to test the hypothesis that early atherosclerosis, induced by a high cholesterol diet in rabbits, is characterized by significant ultrastructural change in the elastic laminae of the aortic valve. However, it is not known whether this process is also taking place in the cardiac valve at the early stage of atherosclerosis. Animals were fed either a high cholesterol diet (n = 5) or a control diet (n = 5) for 10-12 weeks. Histologic analysis demonstrated that subendothelial thickening and foam-cell infiltration were evident in the arterialis of aortic valves. Confocal microscopy revealed an altered pattern characterized by fragmentation and disorganization of the arterialis elastic laminae of hypercholesterolemic valves. Computerized digital analysis of the images obtained by confocal scanning microscopy demonstrated that compared to normal valves, the arterialis elastic laminae of hypercholesterolemic valves decreased in percentage of their elastin content (29.03 +/- 1.10% vs. 42.94 +/- 1.35%, p = 0.023). Immunohistochemical staining for matrix metalloproteinase-3 (MMP-3) revealed MMP-3 immunoreactivity was increased in hypercholesterolemic valves, predominantly in the arterialis. This study demonstrated that early atherosclerosis, induced by a high cholesterol diet in rabbits, is characterized by significant ultrastructural change in the elastic laminae of the aortic valve. The arterialis endothelium of the aortic valve may be a more atherosclerosis-prone area compared with the ventricularis. The presence of ultrastructural defect in the elastic laminae may play a role in chronic degenerative change and a resultant valvular dysfunction.

Reduced lymphocyte proliferation and interleukin-2 production in anxiety disorders

OBJECTIVE

The purpose of this study was to examine the effect of anxiety on cell-mediated immunity.

METHOD

The subjects consisted of 31 patients with anxiety disorders and 31 normal controls, who were gender-matched. Cell-mediated immune function was measured by the lymphocyte proliferative response to phytohemagglutinin (PHA), Interleukin-2 (IL-2) production, and natural killer cell activity (NKA). The extent of anxiety was assessed by the Hamilton rating scale for anxiety and the anxiety subscale of symptom checklist-90 revised (SCL-90-R).

RESULTS

The patients with anxiety disorders were significantly lower than the normal controls in lymphocyte proliferative response to PHA and IL-2 production. However, there was no significant difference in NKA between the two groups. Also, no significant correlation was found between the duration of illness or the degree of anxiety and each immune measure in patients with anxiety disorders.

CONCLUSIONS

The results suggest a reduced cell-mediated immune function in patients with anxiety disorders, compared with normal controls. These findings also imply that a variety of immune measures should be assessed at the same time in this kind of psychoneuroimmunology research. This would help elucidate the relationship between anxiety and immune function, which has been unclear in most previous research using a single immune measure.

Evaluation of urinary cadmium and lead as markers of background exposure of middle-aged women in Korea

OBJECTIVE

The present study was initiated to investigate the validity of cadmium (Cd) and lead (Pb) in urine in comparison with the metals in blood as a biological marker of nonoccupational exposure of general populations to these metals as environmental pollutants.

DESIGN

Peripheral blood samples, morning spot-urine samples, and 24-h total food duplicate samples were collected from 107 nonsmoking women (aged 30-59 years) in four urban and rural survey sites in Korea.

METHODS

Portions of the samples were digested by heating in the presence of mineral acids, and the digests were analyzed for Cd and Pb by graphite furnace atomic absorption spectrophotometry. The metal concentrations in urine were adjusted for creatinine concentration and a specific gravity of 1.016. The analyte levels were evaluated on an individual basis (n = 107) and also on a group basis, i.e., in terms of geometric means for the survey sites (n = 4).

RESULTS

Cd in urine correlated with Cd in blood on an individual as well as survey-site basis and tended to correlate with Cd in food duplicates on a group basis. The correlation of Pb in urine with Pb in blood was weaker than that of Cd in urine with Cd in blood when evaluated on an individual and survey-site basis. Pb in urine correlated with Pb in food duplicates either weakly or even negatively when examined on a survey-site basis.

CONCLUSIONS

Cd in urine proved to be valid as a biological marker of environmental exposure of general populations, whereas less support was obtained for Pb in urine as an exposure marker.

Hemodynamic effects of the geometric dimensions of graft vessels in coronary artery bypass graft models

The objectives of this investigation are to evaluate the rheologic properties in atherosclerotic disease treated with the various coronary artery bypass graft (CABG) models by numerical analysis, we used four different CABG models for the assessment of spatial fluctuation in wall shear stress, pressure variation and mass flow rate with Carreau model and Navier-Stokes equation. Wall shear stress was higher in a naturally tapered model (model 1) and a constant (non-tapered) diameter of the graft vessel the same as the distal LAD (model 4) than in others. Pressure variation along the native coronary artery and graft vessels was higher in a model 4, model 1 than in a reverse tapering model (model 2) and a constant diameter of the graft vessel the same as the proximal LAD (model 3). The mass flow rate of the distal part (kg/sec,.m(o)) was the highest in model 3. This study suggests that in vitro spatial simulation following CABG revealed that small caliber or tapered graft vessels have adverse hemodynamic effects on the native and graft vessels. By this technique it is possible to simulate the optimal distribution of local hemodynamic variables in patients treated with CABG, also to minimize the degeneration of graft vessel.

Computed numerical analysis of the biomechanical effects on coronary atherogenesis using human hemodynamic and dimensional variables

The objectives of this investigation were to evaluate biomechanical factors in the atherosclerotic process using human in vivo hemodynamic parameters and computed numerical simulation qualitatively and quantitatively. The three-dimensional spatial patterns of steady and pulsatile flows in the left coronary artery were simulated, using a finite volume method. Coronary angiogram and Doppler ultrasound measurement of the proximal left coronary flow velocity were performed in humans. Inlet wave velocity distribution obtained from in vivo data of the intravascular Doppler study allowed for input of in vitro numerical simulation. Hemodynamic variables, such as flow velocity, pressure and shear stress of the left anterior descending coronary bifurcation site were calculated. We found that there were spatial fluctuation of flow-velocity and recirculation areas at the curved outer wall of the left anterior descending coronary artery, which were due to the differences of flow-velocity and shear stress, especially during the declaration phase of pulsatile flow. This study suggests that rheologic properties may be a part of the atherogenic process in the coronary bifurcated and curved areas.

Aminolevulinic acid dehydratase genotype mediates plasma levels of the neurotoxin, 5-aminolevulinic acid, in lead-exposed workers

The first intermediate substrate in the heme synthetic pathway, 5-aminolevulinic acid (ALA), is neurotoxic in animal models and may be responsible for some of the adverse neurologic outcomes in lead poisoning and porphyria in adult humans. ALA is a substrate for the enzyme aminolevulinic acid dehydratase (ALAD; EC 4.2.1.24), which is encoded by the ALAD gene containing 2 co-dominant alleles, 1 and 2. We measured plasma ALA (ALAP) and urinary ALA (ALAU) in 65 Korean lead workers, of whom 44 were homozygous for ALADI (ALAD1-1 genotype) and 21 were heterozygous for ALAD (ALAD1-2 genotype). ALAP in subjects with the ALAD1-1 genotype was significantly higher than in those with the ALAD1-2 genotype (Wilcoxon rank sum test, P = 0.01). No difference between ALAD genotypes was found for age, zinc protoporphyrin (ZPP), blood lead levels (PbB), ALAU, or ALAU adjusted for creatinine. ALAP was significantly correlated with ZPP (Spearman's r = 0.38, P = 0.002) and with PbB (r = 0.34, P = 0.006), and marginally with employment duration (r = 0.22, P = 0.08). ALAP remained significantly elevated (P = 0.032) in ALAD1-1 subjects after adjustment for PbB and age by multiple linear regression. These results suggest that ALAD1-1 subjects respond differently and may be more susceptible than ALAD1-2 subjects to the ALA-mediated neurotoxic effects of lead.

Lemierre's syndrome

Lemierre's syndrome is an acute medical condition characterized by anaerobic oropharyngeal infection leading to septic thrombophlebitis of the internal jugular vein. The illness is often complicated by septic pulmonary emboli and distant metastatic infections. Treatment consists of surgical drainage of purulent collections and long-term intravenous antibiotic therapy. Although Lemierre's syndrome is rare, it is potentially fatal and remains an important entity for clinicians to recognize and treat appropriately.

delta-Aminolevulinic acid dehydratase genotype modifies four hour urinary lead excretion after oral administration of dimercaptosuccinic acid

OBJECTIVES

Previous research suggests that binding of lead by delta-aminolevulinic acid dehydratase (ALAD) may vary by ALAD genotype. This hypothesis was tested by examining whether ALAD genotype modifies urinary lead excretion (DMSA chelatable lead) after oral administration of dimercaptosuccinic acid (DMSA).

METHODS

57 South Korean lead battery manufacturing workers were given 5 mg/kg oral DMSA and urine was collected for four hours. Male workers were randomly selected from two ALAD genotype strata (ALAD1-1, ALAD1-2) from among all current workers in the two plants (n = 290). Subjects with ALAD1-1 (n = 38) were frequency matched with subjects with ALAD1-2 (n = 19) on duration of employment in the lead industry. Blood lead, zinc protoporphyrin, and plasma aminolevulinic acid concentrations, as well as ALAD genotype, duration of exposure, current tobacco use, and weight were examined as predictors or effect modifiers of levels of DMSA chelatable lead.

RESULTS

Blood lead concentrations ranged from 11 to 53 micrograms/dl, with a mean (SD) of 25.4 (10.2) micrograms/dl. After 5 mg/kg DMSA orally, the workers excreted a mean (SD) 85.4 (45.0) micrograms lead during a four hour urine collection (range 16.5-184.1 micrograms). After controlling for blood lead concentrations, duration of exposure, current tobacco use, and body weight, subjects with ALAD1-2 excreted, on average, 24 micrograms less lead during the four hour urine collection than did subjects with ALAD1-1 (P = 0.05). ALAD genotype seemed to modify the relation between plasma delta-aminolevulinic acid (ALA) and DMSA chelatable lead. Workers with ALAD1-2 excreted more lead, after being given DMSA, with increasing plasma ALA than did workers with ALAD1-1 (P value for interaction = 0.01).

CONCLUSIONS

DMSA chelatable lead may partly reflect the stores of bioavailable lead, and the current data indicate that subjects with ALAD1-2 have lower stores than those with ALAD1-1. These data provide further evidence that the ALAD genotype modifies the toxicokinetics of lead-for example, by differential binding of current lead stores or by differences in long-term retention and deposition of lead.

Associations of subtypes of hemoglobin with delta-aminolevulinic acid dehydratase genotype and dimercaptosuccinic acid-chelatable lead levels

Hemoglobin in erythrocytes may be an important intravascular site of lead binding. We examined associations of hemoglobin subtypes A1 and A2 with delta-aminolevulinic acid dehydratase (ALAD) genotype, a protein that is another important site of erythrocyte lead binding. After oral administration of dimercaptosuccinic acid (DMSA-chelatable lead), we also examined 4-h lead excretion, which provides an estimate of bioavailable lead stores. We randomly selected 57 South Korean current lead battery manufacturing workers from two plants (N = 290 employees) and from two ALAD genotype strata (ALAD1-1 and ALAD1-2). These workers voluntarily administered 5 mg/kg oral DMSA. We frequency-matched subjects with ALAD1-1 (n = 38) to subjects with ALAD1-2 (n = 19) with respect to duration of employment in the lead industry. Blood lead levels ranged from 11 to 53 microg/dl (mean +/- standard deviation, 25.4 +/- 10.2 microg/dl). After administration of oral DMSA, workers excreted a mean lead level of 85.4 (standard deviation, 45.0 microg; range, 16.5-184.1 microg). Hemoglobin A1 and A2 ranged from 3.7% to 9.9% and 1.6% to 5.9%, respectively (mean +/- standard deviation, 6.2 +/- 1.0% and 2.7 +/- 0.8%, respectively). Subjects with ALAD1-1 had elevated mean hemoglobin A1 levels (adjusted p = .05). In addition, higher hemoglobin A1 levels were associated with higher DMSA-chelatable lead levels (adjusted p = .03). This, as well as the results of prior research, suggest that both ALAD and hemoglobin A1 may be important lead-binding sites that influence urinary lead excretion after administration of DMSA.

Nutritional evaluation of women in urban and rural areas in Korea as studied by total food duplicate method

Nutrient intake was studied by the total food duplicate method in 141 adult working women (at the ages of 21 to 56 years) in four regions (Seoul, Pusan, Chunan and Haman) in Korea. Clinical, hematological and anthropometrical examinations were conducted in parallel. The nutrient intakes were estimated in reference to the weight of each food item and the national standard food composition tables for Korean population, and evaluated in comparison with the nationally recommended dietary allowances (RDA). The intakes were essentially sufficient when evaluated on a group basis. Plant-based foods were major sources of both protein (67%) and lipid (72%). Dinner was the most substantial sources of all nutrients. Further evaluation on an individual basis taking 80-120% RDA as acceptable showed that young people (at the ages of 20-29 years) and those in Seoul had highest prevalence of insufficient intake of nutrients, especially energy, protein and iron. Consumption of rice, the traditional staple food, was the lowest in Seoul and in the youngest groups as compared with others. The prevalence of overweight cases was also the lowest in the Seoul participants. The two observations when combined apparently suggest the difficulties in public nutrition.

Ethnic variation in the prevalence of a common NAD(P)H quinone oxidoreductase polymorphism and its implications for anti-cancer chemotherapy

The NAD(P)H quinone oxidoreductase (NQO1:EC 1.6.99.2) is an important biotransformation enzyme system that is also known to metabolize important novel chemotherapeutic compounds. The gene that codes for this enzyme has recently been found to be polymorphic in humans. Here, we describe the ethnic distribution of the polymorphism and note that this may have implications for anti-tumour drug development and use.

The effect of diphenyl-dimethyl-dicarboxylate on cyclosporine-A blood level in kidney transplants with chronic hepatitis

An adequate blood level of cyclosporine-A (CsA) is essential to keep graft function in kidney transplants. Due to a narrow therapeutic index and highly variable pharmacokinetic properties associated with CsA, drug interactions may have a significant impact on the immunosuppressive efficacy or toxicity of CsA. Numerous drug interactions of potential clinical significance involving CsA have been reported. Dephenyl-dimethyl-dicarboxylate (PMC), a hepatotonic drug, is a substance derived from the synthesis of Schizandrae fructus elements. We have experienced two cases of drug interaction between CsA and PMC in kidney transplants with chronic hepatitis. In both cases, CsA troughs decreased markedly to a subtherapeutic level following administration of PMC. We, therefore, suggest that PMC could decrease the CsA trough level and thus a close monitoring of the CsA trough level is necessary during a PMC therapy.

Sex-determining genes on mouse autosomes identified by linkage analysis of C57BL/6J-YPOS sex reversal

A powerful approach for identifying mammalian primary (gonadal) sex determination genes is the molecular genetic analyses of sex reversal conditions (that is, XX individuals with testicular tissue and XY individuals with ovarian tissue). Here we determined the number and chromosomal location of autosomal and X-linked genes that cause sex reversal in C57BL/6J (B6) mice carrying a Y chromosome of Mus domesticus poschiavinus origin (YPOS). B6 XYPOS mice develop either as females with exclusively ovarian tissue or as true hermaphrodites with ovarian and testicular tissue. In contrast, the YPOS chromosome is fully masculinizing on most other inbred strain backgrounds. B6-YPOS sex reversal appears to result from the incompatibility of the Sry (sex determining region, Y chromosome) allele carried on the YPOS chromosome with B6-derived autosomal or X-linked loci. We found strong evidence for the location of one gene, designated tda1 (testis-determining, autosomal 1), at the distal end of Chromosome (Chr) 4 and a second gene, tda2, in the central region of Chr 2. A third gene, tda3, on Chr 5 is implicated, but the evidence here is not as strong. We suggest that B6 alleles at these loci predispose XYPOS fetuses to ovarian tissue development, but no single locus or combination of loci is necessary and sufficient to cause sex reversal. The TDA proteins may regulate Sry expression or form complexes with the SRY protein to regulate other genes, or the tda genes may be activated or repressed by the SRY protein.

Assessing myocardial perfusion with Albunex during coronary artery bypass surgery: technical considerations and safety of aortic root injections

OBJECTIVE

To test the safety and report on limiting technical considerations, including optimal dosing of Albunex (Molecular Biosystems, Inc, Mallinckrodt Medical, St. Louis, MO) for myocardial opacification after intra-aortic root injections during cardiac surgery.

DESIGN

This was a prospective randomized study with a control group who did not receive Albunex and a group who received intra-aortic root injections of Albunex.

SETTING

Multicenter (two) independent university hospitals.

PARTICIPANTS

32 patients scheduled for elective coronary artery bypass surgery were evaluated after individual informed consent was obtained.

INTERVENTIONS

2 to 8 mL of Albunex were injected before and after coronary revascularization.

MEASUREMENTS AND MAIN RESULTS

Quality of enhancement in each of four regions of the left ventricle was assessed from a short-axis mid-papillary ultrasound image by three experienced observers blinded to dose. Electrocardiogram (ECG), creatine phosphokinase (CPK) (MB fraction), and hemodynamics were evaluated at baseline and throughout the study period for up to 72 hours. No differences were noted between groups with respect to preoperative and postoperative CPK enzymes (CPK-MB fraction), ECG changes, hemodynamics, requirements for separation from CPB, need for postoperative inotropes, time to extubation, and time to discharge from the intensive care unit. The average total dose of Albunex injected was 19 mL +/- 4 (0.25 mL/kg). A single dose of 4.2 +/- 1.2 mL (0.05 mL/kg) appeared to offer optimal enhancement of contrast effect for myocardial perfusion assessment.

CONCLUSION

Albunex is safe and easy to use for myocardial opacification when administered via an antegrade cardioplegia catheter into the aortic root during CPB.

Association of somatotropin (BST) gene polymorphism at the 5th exon with selection for milk yield in Holstein cows

A selection project produced control cows from continuous matings with breed average bulls for predicted transmitting ability for milk (PTA-milk) in 1964 and select cows from matings to four of the highest PTA-milk bulls each year since 1964. Blood samples were collected in 1992 when milk yield difference of select and control line cows exceeded 3,800 kg of milk/305-day lactation. Genomic DNA from control (n = 49) and select (n = 101) cows was analyzed for the presence of variants associated with amino acid position 127 (leucine, AluI[+]; valine, AluI[-]) of bovine somatotropin (bST). Amplification of a 428 base-pair fragment of the bST gene from individual cows, subsequent restriction enzyme (AluI) digestion, and separation resulting fragments indicated three genotypes AluI(+/+), AluI(+/-), and AluI(-/-) in 110, 39, and 1 animal(s), respectively. Gene frequencies of leucine127 and valine 127 alleles were similar for control (0.867m 0.133) and select (0.861, 0.139) animals. United States Department of Agriculture-PTA values were compared between the two genotypes, AluI(+/+) and AluI(+/-). Estimated breeding value for milk (EBV-milk) and average yield deviation for milk (AYD-milk) were not associated with genotype for control animals. However, presence of the valine allele was correlated with decreased EBV-milk (P = 0.03) and AYD-milk (P = 0.16) in select animals and accounted for a decrease of approximately 170 kg of EBV-milk and 240 kg of AYD-milk.

Signaling mechanism of PMA-induced differentiation of K562 cells

We have studied the signaling pathways responsible for the monocytic and/or megakaryocytic differentiation of K562 cells. The results demonstrated that although the mitogen-activated protein kinase (MAPK) was activated during the phorbol myristate acetate (PMA)-induced monocytic and/or megakaryocytic differentiation of K562 cells, the overexpression of Ha-ras which can activate the MAPK did not induce the monocytic and/or megakaryocytic differentiation of K562 cells. Instead PMA-induced megakaryocytic differentiation of K562 cells was inhibited by the pretreatment of pyrrolidine dithiocarbamate, a specific nuclear factor kappaB (NF-kappaB) inhibitor. Taken together, these results suggest that the activation of NF-kappaB rather than that of MAPK might be involved in the PMA-induced megakaryocytic differentiation of K562 cells.

Clinical significance of serum TSH in euthyroid patients with paroxysmal atrial fibrillation

Atrial fibrillation may occur in patients with a variety of cardiovascular or chronic disease as well as in normal subjects. Many authors reported that atrial fibrillation occurs in patients with thyrotoxicosis. It is reported that a low serum thyrotrophin concentration in an asymptomatic person with normal serum thyroid hormone concentrations can be a independent risk factor for developing atrial fibrillation. But we focused on the significance of serum thyroid stimulating hormone (TSH) in the euthyroid patient with atrial fibrillation whose serum level of T3, T4, fT4, and even TSH were absolutely within normal range. On our results, there was no significant differences in age, sexual distribution, and left ventricular ejection fraction between the patients group of paroxysmal and chronic persistent atrial fibrillation (p > 0.05), but there was larger left atrial dimension (LAD) and more cases of rheumatic heart disease in the chronic persistent atrial fibrillation group and there was more cases of lone atrial fibrillation in the paroxysmal atrial fibrillation group (p < 0.05). There was no significant differences in serum levels of T3, T4, fT4 between paroxysmal and chronic persistent atrial fibrillation, but significantly lower serum TSH was found in patients with paroxysmal atrial fibrillation (p < 0.001), and these findings were more significant after the control of hemodynamic change (p < 0.001 vs p < 0.05). The discriminant value in serum TSH between the paroxysmal and chronic atrial fibrillation group was 1.568U/mL with about 76% of predictive power. There was significantly lower serum TSH in paroxysmal atrial fibrillation in all age groups (p < 0.05). There was a significantly higher prevalence of cerebral thromboembolic events in chronic persistent (27.7%) and disease-associated (15.0% atrial fibrillation than in the paroxysmal (3.3%) and lone (4.5%) atrial fibrillation group (p < 0.001). Therefore, we suggest that serum TSH below the serum concentration of 1.5U/mL can be a risk factor for developing atrial fibrillation when the serum level of T3, T4, fT4, and even TSH were within absolutely normal range.

Associations of delta-aminolevulinic acid dehydratase genotype with plant, exposure duration, and blood lead and zinc protoporphyrin levels in Korean lead workers

Previous studies have suggested that polymorphisms in delta-aminolevulinic acid dehydratase (ALAD), a heme synthetic enzyme, may be associated with differences in blood lead levels, perhaps due to differential binding of lead in erythrocytes. The authors examined associations of ALAD genotype with blood lead and zinc protoporphyrin (ZPP) levels, exposure duration, sex, and plant in 308 currently exposed lead workers in three lead storage battery manufacturing plants in the Republic of Korea in 1993. The overall prevalence of the variant allele, ALAD2, was 11%, but prevalence varied by plant (p = 0.02: 8.6% in plant A, 20% in plant B, and 22% in plant C). While ALAD2 was not associated with mean blood lead levels, the allele was associated with blood lead levels greater than or equal to 40 micrograms/dl (crude odds ratio (OR) = 2.6, 95% confidence interval (CI) 1.1-6.3; adjusted OR = 2.3, 95% CI 0.8-6.2, with adjustment for sex, plant, and exposure duration) and with exposure durations greater than 6 years (adjusted OR = 2.5, 95% CI 1.2-5.4, with adjustment for blood lead, sex, and plant). Among workers in plant C, the highest exposure plant, ALAD2 was associated with lower ZPP levels when controlling for blood lead levels. These data suggest that lead toxicokinetics may be modified by ALAD genotype and that ALAD2 may be protective for the health effects of lead. ALAD genotype also appears to have been a selection factor for current lead exposure status in the studied workers.

Dietary intake of cadmium and lead among the general population in Korea

This survey was conducted in Seoul, Pusan, Chunan, and Haman in Korea to clarify cadmium and lead burden in the general Korean populations in terms of dietary intake of cadmium and lead and the concentrations of the two metals in blood. People who participated in the study were 141 healthy nonsmoking women aged 21-56 years. Determination of cadmium and lead in 24-hr food duplicates and blood samples was carried out by graphite furnace atomic absorption spectrophotometry. The geometric means for the four sites in combination were 21.2 micrograms/day for dietary cadmium, 20.5 micrograms/day for dietary lead, 1.27 ng/ml for blood cadmium, and 44.3 ng/ml for blood lead. Cadmium intake from boiled rice accounted for 23% of total daily cadmium intake. The counterpart value for lead intake from boiled rice was 12%. Blood cadmium levels and dietary cadmium intake were lower and blood lead level and dietary lead intake were higher in Korean women than in Japanese women. The values for dietary cadmium are similar to, and the values for dietary lead are somewhat lower than, the levels reported from Europe and the United States. Dietary intake was the main source of cadmium exposure, whereas lead exposure was from both ambient air and foods in the Korean population.

Evaluation of lead exposure in workers at a lead-acid battery factory in Korea: with focus on activity of erythrocyte pyrimidine 5'-nucleotidase (P5N)

OBJECTIVE

To evaluate lead exposure among lead-acid battery workers in Korea, to evaluate in more detail the erythrocyte pyrimidine 5'-nucleotidase (P5N) test for lead exposure, and to evaluate the abnormal accumulation of erythrocyte pyrimidine nucleotides in the battery workers.

METHODS

Activity of P5N and other biological variables were examined in 66 exposed workers in a lead-acid battery factory and in 26 non-exposed workers in Korea.

RESULTS

At the factory the time-weighted average of 13 (72%) of 18 air samples for lead exceeded 0.05 (range 0.012-0.468) mg/m3. Blood lead concentration (PbB) in 39 of the 66 exposed workers was above 40 micrograms/dl, and the mean (SD) PbB in the exposed group was 45.7 (15.7) micrograms/dl. Compared with the nonexposed group, free erythrocyte protoporphyrin in the exposed group was significantly increased, whereas erythrocyte P5N activity and activity of erythrocyte delta-aminolevulinic acid dehydratase (ALAD) were significantly inhibited. Erythrocyte P5N activity had valid correlation biologically with PbB and with other biological variables, such as ALAD activity. In 28 exposed workers, the concentration of erythrocyte pyrimidine nucleotides (uridine 5'-diphosphate-glucose and cytidine 5'-triphosphate) correlated inversely with P5N activity and positively with PbB.

CONCLUSIONS

These findings show that the depression of erythrocyte P5N activity by lead exposure results in the accumulation of erythrocyte pyrimidine nucleotides. In general, the standard analysis of PbB performed in laboratories around the world remains the most useful index of recent exposure. The results indicate that the erythrocyte P5N activity test provides supporting evidence of lead exposure and shows the effect of lead on nucleotide metabolism.

Ethnic differences in the prevalence of the homozygous deleted genotype of glutathione S-transferase theta

In humans the glutathione S-transferase (GST) genes encode four classes of proteins (GST) important in the detoxification of reactive electrophiles. Recently, a gene deletion polymorphism was discovered within the GST class theta locus that leads to a functional deficiency in GST theta activity within circulating red blood cells. In this study we have examined the ethnic distribution of this polymorphism using a polymerase chain reaction (PCR)-based genotyping method. Five different ethnic groups were studied: North American Caucasians, African-Americans, Mexican-Americans, Chinese and Koreans. The prevalence of the null genotype was highest among Chinese (64.4%), followed by Koreans (60.2%), African-Americans (21.8%) and Caucasians (20.4%), whereas the prevalence was lowest among Mexican-Americans (9.7%). Interestingly, the prevalence of the deleted genotype in Caucasians differed significantly when 257 individuals drawn from a nation wide organization were compared with 185 people from the New England area (23.7 versus 15.7%, P < 0.05, chi 2 test). These results indicate that there are major differences in the prevalence of this trait attributable to ethnicity and that ethnic origin even among Caucasians should be considered in studies of gene-environment interaction involving this polymorphism.

Retrograde-delivered cardioplegia is not distributed equally to the right ventricular free wall and septum

Right ventricular myocardial protection during cardiac surgery continues to be a challenge. Retrograde delivery of cardioplegia has been shown to perfuse left ventricular regions subtended by critical coronary stenosis and not adequately protected by antegrade delivery. However, the distribution of cardioplegia from the coronary sinus to the right ventricle remains in question. A reliable means for assessing such flow distribution intraoperatively is provided by contrast echocardiography. It was hypothesized that conventional use of coronary sinus catheters for retrograde cardioplegia delivery does not reliably perfuse the myocardial region subtended by the right coronary artery. Six patients scheduled to undergo elective coronary artery bypass surgery were evaluated with contrast echocardiography to determine the distribution of retrograde-delivered cardioplegia into the right ventricle. Sonicated Renografin-76 (Squibb Diagnostics, Princeton, NJ) was injected during retrograde delivery of cold crystalloid cardioplegia solution and continuous two-dimensional ultrasound imaging of the heart. On-line videodensitometric analysis was performed with a digital ultrasound system. The area under the curve and peak pixel intensity were determined for the anterior septum, the posterior septum, and the right ventricular free wall for each contrast injection. Recorded VHS videotape images of contrast-enhanced perfusion patterns were also reviewed and scored. On-line acoustic-densitometric analysis showed that right ventricular posterior and anterior septal peak pixel intensities were 4.8 +/- 3.2 and 7.3 +/- 1.5, respectively, compared with only 1.6 +/- 1.2 (p < or = 0.05) in the right ventricular free wall.(ABSTRACT TRUNCATED AT 250 WORDS)

CD34 immunohistochemical staining of bone marrow biopsies in myelodysplastic syndromes

Although it has been shown that the percentage of bone marrow blasts in myelodysplastic syndrome (MDS) constitute the only independent determinant of survival and progression to acute leukemia, the great variability in survival among patients with MDS of similar percentage of blasts has prompted us to investigate new objective, independent prognostic parameters for the selection of high-risk patients. It was suggested that CD34 antigen expression adversely affected the prognosis of acute myelogenous leukemia. However, no study has been published so far on clinical and prognostic significance of CD34 antigen expression in MDS. Bone marrow biopsies from 58 patients diagnosed as primary MDS were studied using QBEND/10, a monoclonal antibody which recognized the human progenitor CD34 antigen on routine aldehyde-fixed, paraffin-embedded samples. The high percentage of CD34-positive cells (above 3% of total bone marrow nucleated cells) was predominantly observed in cases with RAEB-T, CMML, and to a lesser degree in RAEB. But neither age, hemograms, bone marrow findings including percentage of blasts, ALIP, nor leukemic transformation correlated with the percentage of CD34-positive cells. The median actuarial survival time in the high positive group was significantly shorter (12.0 months) than that of the low group (30.0 months; p = 0.028). The high CD34 aggregate (> or = 3) was selectively found in cases with RAEB, RAEB-T, and CMML. The percentage of bone marrow blasts (p = 0.007) and ALIP (p = 0.030) significantly correlated with number of CD34 aggregates.(ABSTRACT TRUNCATED AT 250 WORDS)

Differential responses of CD34-positive acute myelogenous leukemic blasts to the costimulating effects of stem cell factor with GM-CSF and/or IL-3

Stem cell factor (SCF), a c-kit ligand, has a preferential effect on the proliferation of several classes of immature hematopoietic progenitor cells in combination with GM-CSF or IL-3. To analyze the costimulatory role of SCF in leukemic growth, we investigated the effect of SCF in the presence of GM-CSF and/or IL-3 on isolated CD34-positive (CD34+) leukemic blasts from 15 patients with acute myelogenous leukemia (AML). Cultures of CD34+ cells from normal bone marrow were used as controls. When the proliferation of CD34+ AML blasts in the presence of GM-CSF and/or IL-3 were evaluated in vitro for the effects of SCF, two patterns emerged. In one pattern, CD34+ AML blasts responded with a significant increase in DNA synthesis and/or colony formation when SCF was used with GM-CSF and/or IL-3 relative to the growth with SCF alone; This result is consistent with those CD34+ bone marrow cells from normal donors. Six patients (40%) were included in this category. The addition of SCF as a single factor resulted in colony formation in all six of these cases. In the other pattern, nine of the patients (60%) had CD34+ leukemic cells whose growth with SCF plus either GM-CSF, IL-3, or GM-CSF+IL-3, was not significantly different from the growth noted in the presence of SCF alone. Among them seven cases that did not form colonies in response to SCF alone, and one case showing autocrine, background growth were included. In the six cases in which the costimulating effects of SCF were documented, CD34+ c-kit+ blasts comprised 50.5 +/- 18.7% of the CD34+ leukemic blasts-higher than 21.8 +/- 19.4% of cases in which the costimulating effect of SCF was not documented. In the cases showing high c-kit antigen expression (> or = 40%), SCF had a costimulatory effect in 71% (5/7) of the patients. In conclusion, our data indicate that CD34+ leukemic blasts from a good proportion of patients with AML did not respond to the costimulating effects of SCF in the presence of GM-CSF adn/or IL-3, in contrast to those CD34+ bone marrow cells from normal donors. The possible use of SCF for acute leukemia must await further cytogenetic and molecular studies, which should clarify the preferential costimulating role of SCF in normal hematopoiesis.

Provocative chelation with DMSA and EDTA: evidence for differential access to lead storage sites

OBJECTIVES--To validate a provocative chelation test with 2,3-dimercaptosuccinic acid (DMSA) by direct comparison with the standard ethylene diamine tetraacetic acid (EDTA) test in the same subjects; and to compare and contrast the predictors of lead excretion after DMSA with those after EDTA. A metal chelating agent given orally, DMSA may mobilise and enhance the excretion of lead from the storage sites in the body that are most directly relevant to the health effects of lead. A provocative chelation test with DMSA could thus have wide potential application in clinical care and epidemiological studies. METHODS--34 male lead workers in the Republic of Korea were given a single oral dose of 10 mg/kg DMSA, urine was collected over the next eight to 24 hours, and urine volume and urinary lead concentration determined at 0, 2, 4, 6, 8, and 24 hours. Either two weeks before or two weeks after the dose of DMSA 17 of these workers also received 1 g intravenous EDTA followed by an eight hour urine collection with fractionation at 0, 2, 4, 6, and 8 hours. RESULTS--Urinary lead concentration peaked at two hours after DMSA and four hours after EDTA. Lead excretion after DMSA was less than after EDTA, and cumulative excretion after DMSA plateaued at six to eight hours. The two hour and four hour cumulative lead excretions after DMSA were highly correlated with the eight hour total (r = 0.76 and 0.95). In multiple linear regression analyses, blood lead was found to be an important predictor of EDTA-chelatable lead, whereas urinary aminolevulinic acid (ALAU) was associated with DMSA-chelatable lead. Notably, lead excretion after DMSA was greatly increased if EDTA was given first. An earlier dose of EDTA also modified the relation between ALAU and DMSA-chelatable lead in that workers who received EDTA before DMSA showed a much steeper dose-response relation between these two measures. CONCLUSIONS--The predictors of lead excretion after DMSA and EDTA are different and an earlier dose of EDTA may increase lead excretion after a subsequent dose of DMSA. The results suggest that two hour or four hour cumulative lead excretion after DMSA may provide an estimate of lead in storage sites that are most directly relevant to the health effects of lead.

Primate antibody response to immunotoxin: serological and computer-aided analysis of epitopes on a truncated form of Pseudomonas exotoxin

NLysPE38 is a 38-kDa derivative of Pseudomonas exotoxin (PE) in which domain Ia (amino acids 1 to 252) and part of domain Ib (365 to 380) are deleted and an 11-amino-acid N-terminal peptide is added. LMB-1 is an immunotoxin in which the monoclonal antibody B3 is coupled to NLysPE38 near its N terminus. LMB-7 is a single-chain immunotoxin in which the Fv fragment of B3 is fused to PE38. To identify the antigenic regions of PE38, 12 polyclonal serum samples from monkeys immunized with the immunotoxins LMB-1 (six monkeys) and LMB-7 (six monkeys) were tested for their reactivity to a panel of 120 synthetic, overlapping peptides representing the amino acid sequence of NLysPE38. The antibody responses to peptides were similar among the 12 serum specimens, identifying several major immunodominant B-cell epitopes. Predominant reactivity was seen in six locations: amino acids 272 to 287, 341 to 359, 504 to 516, 540 to 564, and 573 to 591 and the C-terminal amino acids 591 to 613. The sera did not react with approximately 75% of the peptides. Furthermore, a computer-aided analysis was done to predict the immunologically relevant areas and revealed the same antigenic regions defined by serum reactivity to peptides. Competition enzyme-linked immunosorbent assays and neutralization assays were performed with domain II, III, or III plus Ib of PE38 and confirmed the immunodominance of domain III. To analyze the role of specific amino acids in antibody binding, individual amino acids of PE38 with large accessible surface areas were altered by site-directed mutagenesis. These results also show that the predicted areas of immunogenicity agree with the reactivity of the anti-PE38 antibodies to peptides and to the mutants of PE.

The relationship between immediate outcome after cardiac surgery, homogeneous cardioplegia delivery, and ejection fraction

BACKGROUND

Optimal myocardial protection during cardiac surgery with ischemic arrest is predicated on among other variables, homogeneous cardioplegia distribution. Contrast echocardiography has been shown to provide information regarding the intramyocardial distribution of cardioplegia solution. To test the hypothesis that information regarding cardioplegia distribution derived from contrast echocardiography may be associated with immediate clinical outcome after cardiac surgery, data from 21 patients were examined retrospectively.

METHODS

Contrast-enhanced cardioplegia distribution patterns of the left ventricle short axis view obtained with transesophageal echocardiography were examined off-line by four observers blinded to clinical outcome. Contrast effect was scored for eight equally divided myocardial segments (0 = no contrast, 1 = nonuniform contrast, 2 = uniform contrast, 3 = excessive contrast). The scores were then averaged between segments and between observers to generate an antegrade, a retrograde, and a combined global contrast score for each patient.

RESULTS

Seventeen patients were separated from bypass without difficulty (group A) and 4 patients required sustained inotropic therapy or an intra-aortic balloon pump to facilitate separation from bypass (group B). As would be expected, group A patients had a higher average preoperative ejection fraction than did group B patients (60 percent +/- 14 vs 31 percent +/- 7, p < 0.01). In group A, however, for 4 of 17 patients (23 percent), low preoperative ejection fraction was not predictive of postoperative exogenous circulatory support requirements. Group A patients also had significantly higher antegrade (1.6 vs 1.2, p < 0.02), retrograde (1.7 vs 1.1, p < 0.02), and combined global contrast scores (1.7 vs 1.1, p < 0.01) than did group B patients. All patients with low preoperative ejection fraction and low intraoperative contrast scores required exogenous support to separate from cardiopulmonary bypass.

CONCLUSION

Contrast echocardiography makes possible an evaluation of the intensity and distribution of contrast-enhanced cardioplegia delivery and we believe the efficacy of intraoperative myocardial protection. Although low preoperative ejection fraction is a known predictor of poor immediate postoperative outcome following cardiac surgery, not all patients with low preoperative ejection fractions require inotropic support postoperatively. Our results suggest that monitoring cardioplegia distribution with contrast echocardiography may offer insight for better patient stratification based on intraoperative myocardial protection in patients with low ejection fraction. We believe a more extensive evaluation of this relationship should be pursued in a prospective manner.

Impaired endothelium-dependent vasodilation in patients with insulin-dependent diabetes mellitus

BACKGROUND

Endothelium-dependent vasodilation is abnormal in experimental models of diabetes mellitus. We postulated that abnormalities of endothelial function are also present in patients with insulin-dependent diabetes mellitus and may contribute to the pathogenesis of vascular disease in these individuals.

METHODS AND RESULTS

Vascular reactivity was measured in the forearm resistance vessels of 15 patients with insulin-dependent diabetes mellitus and 16 age-matched normal subjects. No patient had hypertension or dyslipidemia. Each subject was pretreated with aspirin to inhibit endogenous production of prostanoids. Methacholine chloride (0.3 to 10 micrograms/min) was administered via the brachial artery to assess endothelium-dependent vasodilation. Sodium nitroprusside (0.3 to 10 micrograms/min) and verapamil (10 to 300 micrograms/min) were infused intra-arterially to assess endothelium-independent vasodilation; phenylephrine (0.3 to 3 micrograms/min) was administered to examine vasoconstrictor responsiveness. Forearm blood flow was determined by venous occlusion plethysmography, and dose-response curves were generated for each drug. Basal forearm blood flow in diabetic and normal subjects was comparable (2.6 +/- 0.2 versus 2.1 +/- 0.3 mL x 100 mL-1 x min-1, respectively; P = NS). The forearm vasodilative response to methacholine was less in diabetic than in normal subjects. At the highest dose of methacholine, the forearm blood flow increased 9.5 +/- 1.1 mL x 100 mL-1 x min-1 in diabetic subjects and 15.3 +/- 1.4 mL.100 mL-1 x min-1 in normal subjects (P < .01). The forearm blood flow responses to nitroprusside and verapamil and the forearm vasoconstrictor responses to phenylephrine were similar in diabetic and healthy subjects. In diabetic subjects, endothelium-dependent vasodilation correlated inversely with serum insulin concentration but not with glucose concentration, glycosylated hemoglobin, or duration of diabetes.

CONCLUSIONS

Endothelium-dependent vasodilation is abnormal in forearm resistance vessels of patients with insulin-dependent diabetes mellitus. This abnormality may be relevant to the high prevalence of vascular disease that occurs in these individuals.

Structure of the hormone binding domain of human beta 1 thyroid hormone nuclear receptor: is it an alpha/beta barrel?

To understand the structure of the hormone binding domain (HBD) of human beta 1 thyroid hormone nuclear receptor (h-TR beta 1), truncated h-TR beta 1 fragments, MD32 (M169-D456), KD29 (K201-D456), DD28 (D211-D456), KD25 (K235-D456), and KP28 (K201-P448), were analyzed by circular dichorism (CD). MD32 and KD29 show intense CD spectra with double minima at 222 and 208-210 nm, indicating the presence of extensive regions of alpha-helix. DD28 and KD25 have spectra which are reduced in intensity with minima around 215 nm, characteristic of a beta-sheet. The observed spectra are compatible with sequence analysis which predicts that HBD contains alternating stretches of alpha-helix and beta-strand. These extensive decreases in secondary structure in DD28 and KP28 in which the predicted first beta-strand or last alpha-helix was deleted, respectively, were accompanied by the loss of hormone binding activity. On the basis of these results, we suggest a new model for h-TR beta 1 consisting of the known DNA binding domain linked by an alpha-helical hinge to the HBD, with the tertiary structure of an alpha/beta barrel. The model is compatible with previous chemical and genetic studies on the structure of this protein.

Studies on IL-2 production and T-cell colony forming unit in patients with chronic renal failure

To elucidate the nature of altered cellular immunity seen in patients with chronic renal failure, the values of interleukin-2 (IL-2), a kind of lymphokine, and T-cell colony forming units were measured in controls (N = 10), predialysis uremic patients (N = 14), patients undergoing chronic hemodialysis (HD, N = 11) and patients on continuous ambulatory peritoneal dialysis (CAPD, N = 9). Dialytic patients were selected as relatively stable cases receiving dialysis for more than 3 months. The duration of dialysis was 25.5 +/- 5.5 months in HD and 14.7 +/- 3.0 months in CAPD groups. The mean age was 30.3 years in the control, 36.1 years in the predialysis, 32.9 years in the HD and 41.1 years in the CAPD groups; all 4 groups showed male predominance. The serum creatinine concentration of each group was 1.2 +/- 0.1 mg/dl in the control, 14.1 +/- 0.9 mg/dl in predialysis, 13.5 +/- 1.3 mg/dl in HD and 14.7 +/- 0.9 mg/dl in CAPD groups. The level of IL-2 in the predialysis group was markedly lower compared to the control, HD and CAPD groups (as 3.1 +/- 0.8 unit vs. 8.8 +/- 2.2 unit, 11.8 +/- 3.0 unit and 14.9 +/- 3.4 unit, respectively, p < 0.05); the difference between the control and dialytic groups was not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Recombinant immunotoxins containing the VH or VL domain of monoclonal antibody B3 fused to Pseudomonas exotoxin

We prepared recombinant immunotoxins in Escherichia coli in which the VH or VL domains of mAb B3 were fused to a truncated form of Pseudomonas exotoxin (PE) (PE38KDEL). mAb B3 binds to a carbohydrate Ag found on the surfaces of many types of cancers and only a few normal tissues. PE38KDEL is a 38-kDa form of PE (66 kDa) that is missing the cell-binding domain of PE and has the carboxyl end changed from REDLK to KDEL. We show that immunotoxins in which the H chain or the L chain V region is fused to PE38KDEL bind to and kill carcinoma cells containing the B3 Ag. B3 Ag-negative cells were not affected. The cytotoxicity of these molecules is between 20- and 100-fold less than B3(Fv)-immunotoxins, containing both the H and L chain V regions. The VL-containing toxin was more active than the VH-containing toxin, indicating that the L chain of mAb B3 probably contributes more to Ag-binding than the H chain. Refolding experiments show that B3(VL)-PE38KDEL aggregates less than the VH-derivative or than a single chain immunotoxin B3(Fv)-PE38KDEL, which contains both domains in a single chain form. Furthermore, in addition to monomers, active homodimers of B3(VH)- and B3(VL)-PE38KDEL were obtained from renaturation experiments. The VL-toxin dimers, which might have their binding regions arranged in a manner similar to Bence Jones proteins (L chain homodimers), were found to have almost the same cytotoxicity as the monomers, whereas the VH-toxin dimers had decreased cytotoxic activity.

Recombinant immunotoxins containing the VH or VL domain of monoclonal antibody B3 fused to Pseudomonas exotoxin

We prepared recombinant immunotoxins in Escherichia coli in which the VH or VL domains of mAb B3 were fused to a truncated form of Pseudomonas exotoxin (PE) (PE38KDEL). mAb B3 binds to a carbohydrate Ag found on the surfaces of many types of cancers and only a few normal tissues. PE38KDEL is a 38-kDa form of PE (66 kDa) that is missing the cell-binding domain of PE and has the carboxyl end changed from REDLK to KDEL. We show that immunotoxins in which the H chain or the L chain V region is fused to PE38KDEL bind to and kill carcinoma cells containing the B3 Ag. B3 Ag-negative cells were not affected. The cytotoxicity of these molecules is between 20- and 100-fold less than B3(Fv)-immunotoxins, containing both the H and L chain V regions. The VL-containing toxin was more active than the VH-containing toxin, indicating that the L chain of mAb B3 probably contributes more to Ag-binding than the H chain. Refolding experiments show that B3(VL)-PE38KDEL aggregates less than the VH-derivative or than a single chain immunotoxin B3(Fv)-PE38KDEL, which contains both domains in a single chain form. Furthermore, in addition to monomers, active homodimers of B3(VH)- and B3(VL)-PE38KDEL were obtained from renaturation experiments. The VL-toxin dimers, which might have their binding regions arranged in a manner similar to Bence Jones proteins (L chain homodimers), were found to have almost the same cytotoxicity as the monomers, whereas the VH-toxin dimers had decreased cytotoxic activity.

Myocardial distribution of cardioplegic solution after retrograde delivery in patients undergoing cardiac surgical procedures

The myocardial distribution of both antegrade and retrograde cardioplegia for cardiac surgical intervention, after induction of cardioplegia via the aortic root, was directly assessed and compared in 19 patients by means of contrast echocardiography. Two-dimensional transesophageal echocardiographic images of the short axis of the left ventricle at the level of the papillary muscles were obtained after sonicated Renografin-76 microbubbles were injected into an aortic root and/or transatrial coronary sinus catheter during delivery of cardioplegic solution. Segmental distribution of cardioplegic solution was immediately noted in the myocardium at the time of contrast injections. In 11 of 18 patients (61%) cardioplegic solution was dispersed to all left ventricular myocardial segments after antegrade delivery. In 17 of 19 patients (90%) retrogradely delivered cardioplegic solution (after antegrade induction of cardioplegia in 18 of the 19 patients) was dispersed to all the left ventricular myocardial segments, including the septum. In 2 of the patients, initial lack of retrograde distribution of cardioplegic solution was remedied when the coronary sinus catheter was repositioned and contrast cardioplegic solution was reinjected. Imaging of the right ventricle was possible in only 4 of the 19 patients and revealed that after retrograde delivery, cardioplegic solution had been at least partially distributed to the right ventricle as well. We performed off-line videodensitometric analysis in 9 patients after retrograde delivery of cardioplegic solution. Mean peak pixel-intensity ratio of flow from the endocardium to the epicardium in the left ventricular free wall was 1.46 +/- 0.27, and mean peak pixel-intensity ratio of flow from the left to the right intraventricular septal endocardium was 1.39 +/- 0.33 (p < or = 0.05).

The effect of respiratory protection with biological monitoring on the health management of lead workers in a storage battery industry

Respiratory protection with maintenance free respirator and regular biological monitoring with the measurement of zinc protoporphyrin for one year period not only made significant decreases of biological indices indicative of lead exposure (blood lead, delta-aminolevulinic acid in urine) in a storage battery workers, but also reduced the prevalence of lead related symptoms.

Localization of insulin-2 (Ins-2) and the obesity mutant tubby (tub) to distinct regions of mouse chromosome 7

A DNA mapping panel derived from an interspecific backcross was used to position the mouse insulin-2 locus (Ins-2) on Chromosome 7, near H19 (0/114 recombinants) and Th (1/114 recombinants). Ins-2 is part of a human-mouse conserved linkage group that includes Th, H19, and Igf-2. Analysis of segregation in the F2 generation from the cross C57BL/6J-tub/tub x CAST/Ei demonstrated that Ins-2 and the obesity mutant tubby (tub) are distinct loci, thus eliminating Ins-2 as a candidate gene for tub. These results also refine the estimated genetic distance between tub and Hbb to 2.4 +/- 1.4 cM. The predicted location for a human homolog of tubby is HSA 11p15.

Polyadenylic: polyuridylic acid-induced determinants of host resistance to cytomegalovirus and their potentiation by hyperthermia

The ability of spleen cells from poly A:poly U-treated mice to inhibit murine cytomegalovirus (MCMV) replication in confluent monolayer cells of secondary mouse embryo fibroblasts (MEFs) cultured at 37 and 40 degrees C was investigated. When spleen cells from BALB/c mice injected 48 h earlier with poly A:poly U were added to MEFs infected 2 h previously with MCMV, 37% less plaques were observed than in cultures containing control cells. Of interest, the poly A:poly U-induced antiviral activity at the elevated temperature (40 degrees C) resulted in a further drop to 61% in MCMV-induced plaques compared to those of the normothermic (37 degrees C) cultures. The antiviral function of spleen cells induced by poly A:poly U was evident in the supernatant fluid when cultured for 48 h at 37 degrees C. MCMV-induced plaques were reduced to 52 and 5% of controls in the plaque assays performed at 37 and 40 degrees C, respectively. Supernatant fluids generated at 40 degrees C, however, inhibited MCMV replication only when incubated at 40 degrees C. No direct inhibitory effect of the supernatant fluids on MCMV was evident; rather, inhibition was effected directly on the MEFs. The NK cell fraction of spleen cells from poly A:poly U-treated mice alone showed only a slight inhibitory effect at 40 degrees C. However, in the presence of the supernatant fluid from poly A:poly U-exposed spleen cells, the antiviral activity of NK cells was significantly increased both at 37 and 40 degrees C. The cellular source of the culture fluid showing poly A:poly U-induced antiviral activity appeared to be in the T-cell population. It was completely neutralized by monoclonal anti-IFN gamma antibody but not by anti-IFN beta, anti-IL4, anti-transforming growth factor, or anti-prostaglandin E2. In conclusion, these data document the ability of spleen cells from poly A:poly U-treated mice to inhibit MCMV replication and this activity is potentiated by hyperthermic conditions. The antiviral function of poly A:poly U-treated spleen cells appeared to be due mainly to the action of IFN gamma produced by T cells. The enhanced antiviral activity by hyperthermia appeared to be related to the action of IFN gamma rather than its production.

Telomere-related markers for the pseudoautosomal region of the mouse genome

The pseudoautosomal (PA) region of the mammalian genome is the region of the X and Y chromosomes that shares extensive DNA sequence homology and is of special interest because it may play an essential role during male meiosis. We have identified three telomere-related restriction fragments from the PA region of the mouse genome, using an oligonucleotide probe composed of the mammalian telomere consensus sequence TTAGGG. PA assignment of two C57BL/6J-derived fragments was initially suggested by analysis of DNAs from progeny sired by C57BL/6J males carrying the rearranged Y chromosome, Y*: the hybridization intensity of both fragments was concordant with the sex-chromosome complement of the offspring. Further analysis indicated that both fragments were present in female and male F1, mice regardless of the sex of their C57BL/6J parent--a criterion for autosomal or PA linkage. Both fragments were closely linked to each other and located on the X chromosome distal to amelogenin (Amg)--in agreement with X or PA linkage. Confirmation of the PA derivation of these fragments was accomplished by following their segregation in a cross involving XY* males mated to DBA/2J females. A similar experiment identified a third PA-derived restriction fragment of LT/SvEi origin. Identification of PA-derived telomere-related restriction fragments will enable further genetic analysis of this region of the mouse genome.

Natural killer activity and antibody-dependent cellular cytotoxicity in patients with primary lung cancer

The NK activity and ADCC of peripheral blood mononuclear cell were examined to evaluate the contribution of ADCC and NK activity to host immune response against lung cancer. The NK activity and ADCC were examined in 58 patients with primary lung cancer and 40 healthy volunteers as normal controls. The NK activity of patients with lung cancer was significantly subnormal, but ADCC was at a normal level. The NK activity was decreased in non-small cell lung cancer (NSCLC), but not in small cell lung cancer (SCLC) compared to normal controls. According to stage, the NK activity in stage II, III-M0 and III-M1 NSCLC showed low levels compared to that of stage I NSCLC, but there was no difference of NK activity in patients with SCLC. The NK activity was not affected by performance status. There was no significant difference of ADCC in patients with lung cancer according to cell type, stage and performance compared with that of normal controls. The NK activity and ADCC were not changed after chemotherapy and operation respectively.

Thromboelastogram fails to predict postoperative hemorrhage in cardiac patients

To determine the clinical usefulness of the thromboelastogram in the prediction of postoperative hemorrhage in cardiac patients, we related the results of routine coagulation tests (RCTs) and thromboelastography with the amount of chest tube drainage postoperatively in 101 patients requiring cardiopulmonary bypass. Our data indicated that there was no correlation between RCT results and thromboelastographic variables. No single variable of RCTs and thromboelastography correlated well with the amount of chest tube drainage postoperatively. Before the onset of cardiopulmonary bypass, the most frequent abnormalities detected by thromboelastograms were fibrinolysis and hypocoagulability resulting from factor deficiency. Hypercoagulability detected by thromboelastograms occurred in 13% of patients after cardiopulmonary bypass and usually was not detected by RCTs. The incidence of false-negative thromboelastograms and RCT results in patients who had excessive hemorrhage of unknown cause was 46% and 52%, respectively. The incidence of fibrinolysis as detected by thromboelastograms was similar before and after bypass, but only 2 of the 18 patients with fibrinolysis had excessive hemorrhage postoperatively. Our results indicate that neither RCTs nor thromboelastography predicts the likelihood of excessive hemorrhage in patients after cardiopulmonary bypass. The thromboelastographic results should be interpreted cautiously because of the high rate of unreliable results.

Characterization of the endogenous nonecotropic murine leukemia viruses of NZB/B1NJ and SM/J inbred strains

We characterized 84 endogenous nonecotropic proviruses of NZB/B1NJ and SM/J inbred strains by examining proviral junction fragment segregation in recombinant inbred (RI) and backcross mice. Forty-five proviruses were shared with other laboratory strains, but 28 were unique to NZB/B1NJ or SM/J. Proviral loci were located on 17 of the 19 mouse autosomes and on both sex chromosomes. These markers will facilitate gene mapping in the NXSM RI set and contribute to the pursuit of a more complete map of the mouse genome.

Geographic origin of the Y Chromosomes in ?old? inbred strains of mice

Six distinct Y Chromosomes (Chr) were identified among 39 standard inbred strains of mice with five probes that identified Y Chr-specific restriction fragments on Southern blots. Three Y Chr types, distributed among 31 strains, were of Asian Mus musculus origin. The remaining three Y Chr types, distributed among eight strains, were of M. domesticus origin. The Asian source of the M. musculus Y Chr was confirmed by determining the DNA sequence of 221 bp from an open reading frame within the Sry (sex determining region Y) gene (Gubbay et al., Nature 346: 245-250, 1990) in three inbred strains (C57BL/6J, AKR/J, and SWR/J) and comparing the sequence to the homologous sequences derived from wild caught European and Asian M. musculus males. These data indicate that a minimum of six male mice contributed to the formation of the old inbred strains.

Mapping anti-müllerian hormone (Amh) and related sequences in the mouse: identification of a new region of homology between MMU10 and HSA19p

A panel of 78 backcross progeny, BALB/cJ x (BALB/cJ x CAST/Ei)F1, was used to map the gene encoding anti-Müllerian hormone (Amh), also called Müllerian inhibiting substance, to mouse Chromosome 10 (MMU10). This analysis identified a new region of linkage homology between human Chromosome 19p (HSA 19p) and MMU10 and localized an apparent recombinational hot spot in (C57BL/6J x Mus spretus)F1 females [compared with (BALB/cJ x CAST/Ei)F1 males] to the interval between phenylalanine hydroxylase (Pah) and mast cell growth factor (Mgf). In addition, eight unlinked polymorphic sequences, provisionally designated Amh-related sequences (Amh-rs1 through Amh-rs8), were identified by Southern blot analysis using Amh probes. Amh-rs1, -rs2, -rs4, and -rs7 were mapped to MMU1, 13, 12, and 15, respectively, by recombinant inbred (RI) strain and intraspecific backcross analyses. The NXSM RI strain distribution patterns for the four unmapped loci are also presented.