Molecular genetics of human aldehyde dehydrogenase.

Four non-allelic genes, which encode four different aldehyde dehydrogenase (ALDH) isozymes, have been cloned and characterized at the present time. The coding nucleotide sequences, and organization of introns and exons of these genes have been elucidated. The ALDH1 gene encodes the major cytosolic ALDH1 existing in the liver and other tissues. The genetic deficiency of this isozyme was found at a low frequency (< 10%) in both Caucasians and Orientals. The deficiency and alcohol sensitivity character are inherited together in one large Caucasian family examined. The ALDH1 gene contains two hormone response elements in its upstream 5' region. The ALDH2 gene encodes the major liver mitochondrial ALDH2 which has a very low Km for acetaldehyde. The atypical ALDH2(2) allele is common (about 30%) in Orientals; and subjects with ALDH2(2) allele, both homozygous and heterozygous status, lack ALDH activity. These individuals are alcohol sensitive and have a markedly reduced risk in developing alcoholism and alcoholic liver diseases. The ALDH3 gene produces a cytosolic ALDH3 isozyme existing in the stomach and liver carcinoma but hardly in normal liver. The ALDH3 locus is polymorphic in Orientals and presumably other populations. The ALDH5 gene, which is expressed in testes and liver, is highly polymorphic in both Caucasians and Orientals. The variation of these two loci may affect the development of alcohol-related problems.     

Vasodilator effects of C-type natriuretic peptide on cerebral arterioles in rats

The vasodilator effects of C-type natriuretic peptide (CNP) were investigated in isolated rat cerebral arterioles. CNP caused dose-dependent vasodilation, maximally by 10.0±2.2% at 10⁻⁶ M. The median effective concentration (EC₅₀) was 5.2×10⁻¹⁰ M. In contrast, atrial natriuretic peptide and B-type natriuretic peptide, other members of the natriuretic peptide family, produced little or no vasodilation. Pretreatment with methylene blue (10⁻⁴ M) abolished CNP-induced vasodilation, whereas pretreatment with N^G-monomethyl-

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-arginine or indomethacin did not inhibit vasodilation. Thus, CNP is suggested to cause significant vasodilation in cerebral arterioles via a cyclic guanosine monophosphate-dependent mechanism. © 1997 Elsevier Science B.V. All rights reserved.     

Cyclic AMP-dependent phosphorylation of the rat brain ryanodine receptor.

Phosphorylation of the rat brain ryanodine receptor was studied using a monoclonal antibody, Ry-1, against the cardiac ryanodine receptor. A large polypeptide with the same SDS-PAGE mobility as that of the canine cardiac receptor was detected in rat brain membranes by immunoblotting. The brain ryanodine receptor was solubilized from the microsomal membranes with 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonic acid (CHAPS), and more than 85% of the solubilized receptor was immunoprecipitated by Ry-1. Immunoprecipitated receptors were phosphorylated by cAMP-dependent protein kinase. The ryanodine receptor was also expressed in cultured fetal rat brain neurons and was phosphorylated by treating the cells with dibutyryl cAMP. The number of cells showing a caffeine-induced Ca2+ transient was increased significantly in the phosphorylating condition. These results suggest that the Ca channel activity of the brain ryanodine receptor is regulated by cAMP-dependent phosphorylation.     

Correlation of Nuclear Morphometry and Immunostaining for p53 and Proliferating Cell Nuclear Antigen in Transitional Cell Carcinoma of the Bladder

Background :
In an attempt to determine the biological significance of nuclear morphometric findings, measurements of mean nuclear volume (MNV) and nuclear roundness factor (NRF) were compared to the immunoreactivityof p53 expression and proliferating cell nuclear antigen (PCNA) in human bladder cancer.
Methods :
MNV and NRF were measured using stereological methods. Expression of p53 and PCNA were determined by immunohistochemical staining. Specimens from 111 patients with previously untreated bladder cancer were analyzed.
Results :
The mean MNV was 235.8 ± 1 33.6 μm³ for the 81 patients with p53-labeling index (LI) less than 10% and 337.2 ± 141.0 μn³ for the 30 patients with p53 LI greater than 10% (P = 0.008). There was Resign if icant correlation between NRF and expression of p53. The mean MNV was 220.1 ± 1 20.5 μm³ for the 67 patients with PCNA LI less than 28% (the mean value of PCNA LI) and 328.9 ± 149.2 μm³ in 44 patients with PCNA LI greater than 28% (P= 0.0001). The mean NRF was 80.7 ± 4.2 for the 67 patients with PCNA LI less than 28%, and 82.3 ± 3.4 for the 44 patients with PCNA LI more than 28% (P= 0.04). Conclusion: Nuclear morphometric findings may reflect the proliferative potential of cancer eel Is of the bladder, as indicated by findings of immunostaining for p53 and PCNA.     

Human recombinant erythropoietin directly stimulates B cell immunoglobulin production and proliferation in serum-free medium.

The effect of human recombinant erythropoietin (Epo) on B cell responses was studied in a serum-free medium. Epo enhanced IgM production and thymidine uptake by a human IgM-producing lymphoblastoid cell line, CBL. This effect was specific to Epo since enhancement was blocked by anti-Epo antibody but not by control antibody. Among the various cytokines, interleukin-4 (IL-4) enhanced IgM production and thymidine uptake while IL-6 enhanced IgM production without affecting thymidine uptake. In contrast, other cytokines including IL-1 beta, IL-2, IL-5, interferon-alpha (IFN-alpha), interferon-gamma (IFN-gamma), or granulocyte/macrophage colony-stimulating factor (GM-CSF) were without effect. However, the enhancing effect of Epo is different from that of IL-4 or IL-6, since Epo effect was not blocked by anti-IL-4 antibody or anti-IL-6 antibody. Moreover, specific binding of Epo was detected on CBL cells. Epo also enhanced immunoglobulin (IgG, IgM and IgA) production and thymidine uptake by purified tonsil small resting B cells stimulated by Staphylococcus aureus Cowan strain I (SAC) or by large activated B cells. In contrast, Epo had no effect on unstimulated small resting B cells. These results indicate that Epo could directly stimulate activated and differentiated B cells and could enhance B cell immunoglobulin production and proliferation.     

C3 Deposition in IgA Nephropathy in Children and Adolescents

The aim of this study was to assess the significance of C3 deposition in IgA nephropathy in children and adolescents. One hundred and two patients aged 5–21 years (57 male and 45 female) were studied. The findings of C3 deposition were classified into 8 groups by immunofluorescent (IF) pattern and intensity as follows: group MC3+ (N = 12): mesangiocapillary pattern and 3+ in intensity; group MC2+ (N = 13): mesangiocapillary and 2+; group MC1 + (N = 4): mesangiocapillary and 1 +; group M3+ (N = 11): mesangial and 3+; group M2+ (N = 24): mesangial and 2+; group M1 + (N=18): mesangial 1 +; group S (N = 12): only segmentally positive; and group N (N = 8): negative. Histological changes were scored semiquantitatively as an activity index (cellular proliferation, necrosis, interstitial cell infiltration, and cellular crescents) and a chronicity index (mesangial sclerosis, segmental and global glomerular sclerosis, fibrous crescents, adhesion and tubulo-interstitial change). IF findings were scored semiquantitatively and laboratory findings were also studied. The following results were obtained: 1) The scores of total activity index in MC groups were higher than in the M, S or N groups, and the greater the degree of C3 deposition, the higher the score; 2) Such result was not evident in the chronicity index; 3) High IF scores of IgG and IgM were found in the MC3+ and MC2+ groups; 4) Hematuria was more severe in MC3+ and MC2+ than in other groups, and proteinuria was more prominent in the MC than other groups. Thus the degree of C3 deposition was parallel with histological activity and urinary findings.     

A Clinical Study for the Durability of Oxygenators on Cardiopulmonary Support

Abstract: Cardiopulmonary support (CPS) requires durability of the oxygenator. The life span of the oxygenator is affected by various clinical factors, including patient condition, perfusion condition, and equipment usage. Predictors for the durability of oxygenators were evaluated clinically in this study. Thirty-two patients, who had undergone CPS during the last 3 years in our institute were assigned to this study. Fifty oxygenators had been used (Capiox SX in 19, CB Maxima in 23, and AL-6000 in 8). Significant predictors for the durability of oxygenators were evaluated by nonparametric survival analysis and proportional hazards regression analysis. Univariate regression analysis revealed 6 significant predictors for the life span of oxygenators. These were the oxygenator type, type of centrifugal pump, acidosis with blood pH less than 7.35, base excess less than -5, blood glutamic-oxaloacetic transaminase (GOT) levels greater than 1,000 IU, and blood lactate dehydrogenase (LDH) levels greater than 3,000 IU. After multivariate analysis, there remained only 2 significant predictors. An oxygenator used with a noncoated CPS system (Capiox SX with Capiox EBS) proved to have a significantly shorter life span than one used with a heparin-coated system (CB Maxima or AL-6000 with CB BP-80) (hazards ratio, 3.588, p = 0.0065). Patient conditions, which revealed acidosis with less than -5 of base excess, significantly shortened the life of the oxygenator (hazards ratio, 3.595, p = 0.0188).     

Gadolinium-enhanced breath-hold three-dimensional time-of-flight MR angiography of the abdominal and pelvic vessels: The value of ultrafast MP-RAGE sequences

MR angiography (MRA) was performed in 50 consecutive subjects (mean age, 59 years), who had been referred for abdominal MRA, on a 1.5-T superconductive unit that used a body phased-array coil. Three breath-hold three-dimensional sequences were evaluated both in phantom and clinical studies: (a) standard fast three-dimensional gradient-echo sequence (TR = 15, TE = 6; imaging time, 32 seconds), (b) ultrafast three-dimensional gradient-echo sequence (TR = 8.2, TE = 3; imaging time, 18 seconds), and (c) ultrafast magnetization-prepared (MP) rapid acquisition gradient echo (RAGE) (TR = 5.8, TE = 2.9, inversion time [TI] = 20; imaging time, 15 seconds). The initial 30 patients were randomized into three groups by three separate sequences. For the remaining 20 patients, ultrafast-gradient-echo and ultrafast MP-RAGE sequences were performed. Conventional angiography was performed on 36 patients. Signal measurements of the phantom and clinical images of the aorta, visceral branches of the aorta, iliac arteries, inferior vena cavae, and portal veins were performed. The overall image quality and background fatty tissue contrast of the vessels were rated subjectively. Comparison of images between MRA and conventional angiography also was performed. The contrast between the vessels and background fatty tissue was significantly higher in the ultrafast MP-RAGE sequence in both quantitative and qualitative analysis, and image-quality ultrafast MP-RAGE was superior to the other two sequences (P < .01). The aorta and iliac arteries could be visualized in all pulse sequences, and abnormalities of these vessels were diagnosed correctly. The renal artery was visualized more clearly with the two ultrafast sequences.     

Ileal atresia with perforation in siblings

Two siblings with ileal atresia are described; one boy presented with ileal perforation and the other with meconium peritonitis, diagnosed by antenatal ultrasonography. The site and type of atresia, complications and associated anomalies of reported cases among siblings also are discussed.     

Heterozygous abnormal fibrinogen Osaka III with the replacement of gamma arginine-275 by histidine has an apparently higher molecular weight gamma-chain variant.

Congenitally abnormal fibrinogen Osaka III with the replacement of gamma Arg-275 by His was found in a 38-year-old female with no bleeding or thrombotic tendency. Release of fibrinopeptide(s) by thrombin or reptilase was normal, but her thrombin or reptilase time in the absence of calcium was markedly prolonged and the polymerization of preformed fibrin monomer which was prepared by the treatment of fibrinogen with thrombin or reptilase was also markedly defective. Propositus' fibrinogen had normal crosslinking abilities of alpha- and gamma-chains. Analysis of fibrinogen chains on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in the system of Laemmli only revealed the presence of abnormal gamma-chain with an apparently higher molecular weight, the presence of which was more clearly detected with SDS-PAGE of fibrin monomer obtained by thrombin treatment. Purified fragment D1 of fibrinogen Osaka III also seemed to contain an apparently higher molecular weight fragment D1 gamma remnant on Laemmli gels, which was digested faster than the normal control by plasmin in the presence of [ethylenebis(oxyethylenenitrilo)]tetraacetic acid (EGTA).