[Coronary arterial bypass grafting for angina pectoris suspected with aortitis syndrome: a case report]

We report herein the case of a 56-year-old man with angina pectoris suspected to be accompanied with aortitis syndrome who underwent coronary artery bypass grafting (CABG). His cerebral blood flow consisted of only that of the right vertebralartery, and the marked collaterals of the bronchial artery anastomosing to the coronary artery. CABG was performed under combined with electrical fibrillation and systemic deep hypothermia, for fear of a bad influence on the cerebral tissue by the influx of high potassium cardioplegic solution. The postoperative course was uneventful and the coronary angiography revealed that the all graft were patent.

[Open heart surgery in patients with chronic dialysis]

From January, 1986 to May, 1995, twelve patients with dialysis (11 hemodialysis; HD, and one continuous ambulatory peritoneal dialysis; CAPD) received open heart surgery. They consist of 10 males and two females aged between 35 and 66 with a mean of 58.8. The duration of dialysis was 6.8 years in a mean (the shortest for 2 months and the longest for 16 years). They classified into an equal number of four in NYHA class II, III and IV. Two of them had isolated coronary artery bypass grafting, four had aortic valve replacement (AVR) and two had mitral valve replacement (MVR). Others were each one of AVR and MVR, AVR plus MVR with tricuspid annuloplasty (TAP), AVR plus TAP, and removal of left atrial myxoma. All patients except for one of CAPD were dialysed daily 2 or 3 days before operation. Three patients were managed postoperatively with HD, one with PD, six with continuous hemodiafiltration, and two with continuous hemofiltration. The operative mortality was 25% (3/12). The causes of death were left ventricular rupture, bronchospasm, and respiratory failure. All patients who died were in class in III and IV. For the improvement of the results we emphasize the necessity of early operation that should be scheduled in class II period.

Immunoexpression of the alpha subunit of a guanine nucleotide-binding protein (Go) in pulmonary neuroendocrine cells and neoplasms

The alpha subunit of a GTP-binding protein, Go, was investigated in pulmonary neuroendocrine neoplasms and fetal tissues of the lung by an immunohistochemical method. Positive immunostaining for the alpha subunit of Go (Go alpha) was found predominantly on the cell membrane and found occasionally in the cytoplasm. Typical carcinoids were all positively stained (9/9), and small cell carcinoma showed weaker and less frequent staining (5 positive cases in 10). Atypical carcinoids were variously stained (3/4). The tendency for obvious neuroendocrine differentiation to be immunohistochemically determined in typical carcinoids and not in small cell carcinoma is also true of staining for neuron specific enolase (NSE), chromogranin A (CG-A) and synaptophysin. In the lung, Go alpha-immunostaining was positive not only in nerve tissues but also in the airway epithelium. In the fetal lung, serial sections immunostained for NSE, CG-A and Go alpha confirmed that Go alpha-immunoreactive cells belong to the neuroendocrine cell population. The biological significance of Go alpha is unclear in normal and neoplastic lung tissues, but Go alpha is a useful marker of neuroendocrine cells and neoplasma of the lung.

Testis-specific expression of mRNAs for a unique human type 1 hexokinase lacking the porin-binding domain

Several enzymes in the glycolytic pathway are reported to have spermatogenic cell-specific isozymes. We reported recently the cloning of cDNAs representing three unique type 1 hexokinase mRNAs (mHk1-sa, mHk1-sb, and mHk1-sc) present only in mouse spermatogenic cells and the patterns of expression of these mRNAs (Mori et al., 1993: Biol Reprod 49:191-203). The mRNAs contain a spermatogenic cell-specific sequence, but lack the sequence for the porin-binding domain that somatic cell hexokinases use to bind to a pore-forming protein in the outer mitochondrial membrane. We now report the cloning of cDNAs representing three unique human type 1 hexokinase mRNAs (hHK1-ta, hHK1-tb, and hHK1-tc) expressed in testis, but not detected by Northern analysis in other human tissues. These mRNAs also contain a testis-specific sequence not present in somatic cell type 1 hexokinase, but lack the sequence for the porin-binding domain. The hHK1-tb and hHK1-tc mRNAs each contain an additional unique sequence. The testis-specific sequence of the human mRNAs is similar to the spermatogenic cell-specific sequence of the mouse mRNAs. Furthermore, Northern analysis of RNA from mouse, hamster, guinea pig, rabbit, ram, human, and rat demonstrated expression of type 1 hexokinase mRNAs lacking the porin-binding domain in the testes of these mammals. These results suggest that hexokinase may have unique structural or functional features in spermatogenic cells and support a model proposed by others for hexokinase gene evolution in mammals.

Atypical adenomatous hyperplasia and bronchoalveolar lung carcinoma. Analysis by morphometry and the expressions of p53 and carcinoembryonic antigen

Atypical adenomatous hyperplasia (AAH) of the lung is a putative precursor of bronchoalveolar carcinoma (BAC). To define the steps in its development and to clarify at which stage critical cellular events occur, we studied 65 lesions of AAH, early BAC, and overt BAC by morphometric analysis and immunohistochemical evaluation of expression of p53 protein and carcinoembryonic antigen (CEA). Both the nuclear area and lesion size increased from AAH to early BAC and to overt BAC; the standardized variation of nuclear area was smallest in overt BAC. Discriminant analysis using these morphometric parameters revealed high accuracy rates for the respective categories. Analysis of distribution of lung lesions in terms of nuclear area and lesion size yielded effective, potentially diagnostic cutoff values for distinction between AAH and early BAC. Both p53 and CEA expression tended to increase with the advance of atypia grade. In particular, high-level p53 expression was strongly correlated with overt BAC. These findings indicate that our classification of lung lesions is reproducible and thus useful for analyzing the development of BAC. Furthermore, some kinds of p53 gene abnormalities that are correlated with high-level p53 expression likely play an important role in the progression of early to overt BAC.

Targeted gene disruption of Hsp70-2 results in failed meiosis, germ cell apoptosis, and male infertility

In addition to the five 70-kDa heat shock proteins (HSP70) common to germ cells and somatic tissues of mammals, spermatogenic cells synthesize HSP70-2 during meiosis. To determine if this unique stress protein has a critical role in meiosis, we used gene-targeting techniques to disrupt Hsp70-2 in mice. Male mice homozygous for the mutant allele (Hsp70-2 -/-) did not synthesize HSP70-2, lacked postmeiotic spermatids and mature sperm, and were infertile. However, neither meiosis nor fertility was affected in female Hsp70-2 -/- mice. We previously found that HSP70-2 is associated with synaptonemal complexes in the nucleus of meiotic spermatocytes from mice and hamsters. While synaptonemal complexes assembled in Hsp70-2 -/- spermatocytes, structural abnormalities became apparent in these cells by late prophase, and development rarely progressed to the meiotic divisions. Furthermore, analysis of nuclei and genomic DNA indicated that the failure of meiosis in Hsp70-2 -/- mice was coincident with a dramatic increase in spermatocyte apoptosis. These results suggest that HSP70-2 participates in synaptonemal complex function during meiosis in male germ cells and is linked to mechanisms that inhibit apoptosis.

Electrostatic environment of the tryptophylquinone cofactor in methylamine dehydrogenase: evidence from resonance Raman spectroscopy of model compounds

Methylamine dehydrogenase (MADH) utilizes its endogenous tryptophan tryptophylquinone (TTQ) as a cofactor in enzymatic catalysis, with the C6 carbonyl of the quinone implicated as the site of attack by substrates and other nucleophiles. Resonance Raman (RR) spectroscopy provides an ideal method for investigating the state of this carbonyl group whose C==O stretch is distinct from other vibrational modes of the cofactor and is readily identified by its shift to lower energy in H218O. In a series of indole 6,7-quinone models for TTQ, the in-phase stretching vibration of the two C==O groups occurs at 1650 cm-1 in nonpolar solvents and shifts to 1638 cm-1 in H2O. The absorption maximum undergoes an analogous shift from 400 to 425 mm. The spectral properties of the indole quinones in H2O approach the corresponding values in Thiobacillus versutus MADH (C==O stretch at 1612 cm-1, lamdamax at 440mm) and are indicative of strongly hydrogen bonding of the C==O and NH groups of the cofactor in the native enzyme. Addition of monovalent cations [NH4+,Cs+, and (CH3)3NH+] to MADH causes further increases in the lamdamax and decreases in the frequency of the C==O stretch[1590 cm-1 with (CH3)3NH+]. This implies a strong electrostatic interaction between monovalent cations and a carbonyl oxygen (most likely at C6) in TTQ. The fact that these cations behave as competitive inhibitors of the methylamine substrate suggests that methylamine binds to the same location in the enzyme prior to its covalent reaction with the cofactor. Addition of monovalent cations to the one-electron-reduced semiquinone form MADH results in RR spectral shifts for a number of vibrational modes of the cofactor. Thus, the ability of monovalent cations to promote and stabilize the formation of the semiquinone intermediate is also due to their direct electrostatic interaction with the TTQ cofactor.

Bone scintigraphy as an indicator for dome osteotomy of the pelvis: comparison between scintigraphy, radiography and outcome in 57 hips

We performed dome pelvic osteotomy in 57 hips (54 patients) because of acetabular dysplasia. All patients had preoperative scintigraphy and were followed for more than 2 years. Excellent or good results were obtained in 49 hips, but 8 hips deteriorated. All hips which deteriorated had preoperatively a spotty isotope uptake image localized to the weight bearing area and the medial area of the joint. No hip without this image deteriorated, even when preoperative radiography showed advanced arthrosis. Our findings indicate that bone scintigraphy may be a more reliable predictor of failure for this operation than radiography.

Results of isolated meniscal repair evaluated by second-look arthroscopy

Thirty-six isolated torn menisci in 35 patients (average age, 24 years) which had been repaired arthroscopically using an inside-out technique were evaluated by second-look arthroscopy. The time from meniscal repair to second-look arthroscopy ranged from 2 to 10 months with a mean of 5 months. The indications for meniscal repair were a longitudinal or oblique tear located at the outer half of the meniscus. Twenty (56%) were graded as excellent, 10 (28%) as good, and 6 (16%) were graded as poor. Neither age nor length of time between injury and repair affected meniscal healing. The medial meniscal repairs showed better results than the lateral repairs (rate of excellent results: medial, 82%; lateral, 44%; P < .01, chi-squared test). The rate of excellent results for those with normal meniscal bodies at the time of repair was 79%, which was significantly higher than that seen in the cases with deformed and/or superficial damage to the meniscal body (36%; P < .05, chi-squared test).

Accumulation of cells at G2/M stage by low dose-rate irradiation renders the cell population more susceptible to the subsequent induction of 6-thioguanine-resistant mutations by 252Cf fission neutrons

A previous study on mutagenesis by 252Cf radiation in mouse L5178Y cells showed that the frequency was higher when the dose was delivered chronically, which was in sharp contrast to the results by gamma-rays (Nakamura and Sawada, 1988). A subsequent study using synchronized cells revealed that the cells at G2/M stage were uniquely sensitive to mutation induction by 252Cf radiation but not so by gamma-rays (Tauchi et al, 1993). We carried out the present study to test the possibility that radiation-induced G2 block may be a major determinant of the inverse dose-rate effect following chronic 252Cf radiation. Growing cell population was first subjected to conditioning gamma or 252Cf radiation with different dose-rates, followed by cell cycle distribution analysis and 252Cf mutagenesis. We found that G2/M fraction increased by 3- to 4-fold when the conditioning doses (2 Gy of gamma or 1 Gy of 252Cf radiation) were delivered chronically over 10 hours but only slightly so when the same doses were delivered for 1 hour or less. Subsequent 252Cf irradiation gave higher mutation frequencies in the cells pre-irradiated with gamma-rays over a protracted period of time than in those with higher dose-rate gamma-rays. These results suggest that radiation-induced G2 block would be at least partly (but can not be totally) responsible for the inverse dose-rate effect.

Fas ligand in human serum

The Fas ligand (FasL), a member of the tumor necrosis factor family, induces apoptosis in Fas-bearing cells. The membrane-bound human FasL was found to be converted to a soluble form (sFasL) by the action of a matrix metalloproteinase-like enzyme. Two neutralizing monoclonal anti-human FasL antibodies were identified, and an enzyme-linked immunosorbent assay (ELISA) for sFasL in human sera was established. Sera from healthy persons did not contain a detectable level of sFasL, whereas those from patients with large granular lymphocytic (LGL) leukemia and natural killer (NK) cell lymphoma did. These malignant cells constitutively expressed FasL, whereas peripheral NK cells from healthy persons expressed FasL only on activation. These results suggested that the systemic tissue damage seen in most patients with LGL leukemia and NK-type lymphoma is due to sFasL produced by these malignant cells. Neutralizing anti-FasL antibodies or matrix metalloproteinase inhibitors may be of use in modulating such tissue damage.

[Diffuse ventricular enlargement outlines the late outcome of diffuse axonal brain injury]

Clinical significance of ventriculomegaly after severe head trauma has not been fully explored yet. We analyzed hospital records of 53 cases of diffuse axonal injury and 7 cases of brain concussion together. The follow-up periods ranged from 6 months to 8 years (average 25 months). Four patients underwent CSF shunting without noticeable effect. We classified their outcome according to our modification of the Glasgow outcome scale: vegetated, severe, moderate, mild, fair, and good. We reviewed initial (within 12 hours after injury) CT scans and late (3 to 6 months after injury) CT scans or MRI's. We measured the ratio of the third ventricular width to the inner diameter of the skull on the axial view. We computed the lateral ventricular volume by our newly-devised method which took the partial volume phenomenon into account. Temporary extracerebral fluid accumulation was noted mostly within 3 months after injury in 25 of 39 cases in the mild level or above, and 2 of the 9 fair or good level cases. Ventriculomegaly occurred early and stabilized around the 3 month period. We found the differences between the late and the initial values of the third ventricular width (%) and the lateral ventricular volume (cc) highly correlated with our outcome scale (Spearman's correlation coefficient rs = 0.531, 0.676, respectively with p < 0.001 unanimously). We found the late values themselves of the third ventricular width and the lateral ventricular volume highly correlated with our outcome scale (rs = 0.575, 0.650, respectively with p < 0.001 unanimously). These 4 parameters were also highly correlated with the duration of the initial unconsciousness (LOC). Thus, posttraumatic diffuse ventriculomegaly affecting the third ventricle as well should outline the late outcome of diffuse axonal injury. Both the ventriculomegaly and the late outcome should be roughly predicted by the duration of the initial unconsciousness.

MRI of early osteonecrosis of the femoral head after transcervical fracture

We have carried out a prospective study of 17 patients (14 women, 3 men) of mean age 48 years (21 to 76) with transcervical fractures of the femur using MRI to detect early evidence of avascular necrosis of the head. Two fractures were Garden stage I, 12 stage II, and three stage III. We performed internal fixation under radiological control at a mean of five days (2 to 15) after injury using a titanium cannulated cancellous screw or a titanium compression hip screw. MRI was performed at one, six and 12 months and then yearly after operation. T1- and T2-weighted images were obtained by a spin-echo technique. The duration of follow-up of patients who did not subsequently require replacement of the head of the femur was from 2 to 5 years (mean 3.2). One month after operation eight of the 17 hips showed a band of low signal intensity on T1-weighted images and high signal intensity on T2-weighted images indicating lesions in the femoral head away from the fracture line. These were of three types: type I was a small infarct at the superolateral region of the femoral head and was seen in three hips; type II was a shallow lesion from the superolateral region to the fovea of the femoral head (three hips); and type III was a large lesion occupying most of the femoral head (two hips). No further changes were seen in the MRI after six months from operation. Collapse of the femoral head did not occur in the three hips with type-I lesions, but two of the three type-II hips and both type-III hips subsequently collapsed. At the final follow-up the three hips with a type-I lesion and one with a type-II were still asymptomatic but radiography showed sclerosis in the femoral head corresponding to the MRI lesions. The nine hips which showed no changes on MRI at one month had no abnormal findings on physical examination, radiography or MRI at final follow-up.

[A comparative study on histopathological findings between Alzheimer's disease and senile dementia of Alzheimer type]

Histopathological findings of the brains in 2 cases of Alzheimer's disease (AD) were comparatively studied with those in 2 cases of senile dementia of Alzheimer's type (SDAT). Marked atrophy of the temporal lobe, most conspicuous at the hippocampus and entorhinal cortex was commonly observed in all 4 cases. Microscopic examination revealed in the AD cases various forms of senile plaques including those of primitive type or ones with an amyloid core, while plaques in the cases of SDAT were mostly composed of non-typical forms without an amyloid core. The senile plaques and neurofibrillary tangles (NFT) were widely distributed in the neocortices such as in the frontal, parietal and occipital lobes as well as in the hippocampal and parahippocampal gyri in the cases of AD, while the density of SPs in the neocortices was lower than that in the hippocampal and parahippocampal gyri, and NFTs were scarcely observed in the neocortices in the cases of SDAT. This suggests that we should histopathologically differentiate SDAT from AD, although we found no marked macroscopic differences between the AD brain and SDAT brain.

Biosynthesis of topa quinone cofactor in bacterial amine oxidases. Solvent origin of C-2 oxygen determined by Raman spectroscopy

Resonance Raman spectroscopy is an excellent technique for providing structural information on the 2,4, 5-trihydroxyphenylalanine quinone (TPQ) cofactor in copper-containing amine oxidases. This technique has been used to investigate the copper- and O2-dependent biosynthesis of the TPQ cofactor in phenylethylamine oxidase (PEAO) and histamine oxidase from Arthrobacter globiformis. Incubation of the holoenzyme in H218O causes frequency shifts at 1684(-26) cm-1 in PEAO and at 1679(-28) cm-1 in histamine oxidase, allowing this feature to be assigned to the C=O stretch of a single carbonyl group at the C-5 position. When apoprotein is reacted with Cu(II) and O2 in the presence of H218O, the resultant holoproteins show increased shifts of -3 to -6 cm-1 in a number of other vibrational modes, particularly at 411 and 1397 cm-1. Because these small shifts persist when the H218O-regenerated protein is back-exchanged into H216O, they can be assigned to oxygen isotope substitution at the C-2 postion. No isotope shifts are observed when apoprotein is regenerated with Cu(II) in the presence of 18O2. Thus, it is concluded that the C-2 oxygen atom of TPQ originates from H2O rather than O2. The isotope dependence of the 1397-cm-1 mode allows it to be assigned to the C O moiety at the C-2 position, with its low frequency being indicative of only partial double bond character. Similar frequency shifts due to 18O at C-2 are observed in the resonance Raman spectra of H218O-regenerated PEAO after derivatization of the C-5 carbonyl with either p-nitrophenylhydrazine (-5 cm-1 at 480 cm-1) or methylamine (-5 cm-1 at 1301 cm-1). Taken together, these results indicate that the TPQ cofactor in the native enzyme has substantial electron delocalization between the C-2 and C-4 oxygens and that only the C-5 oxygen has predominantly C=O character.

AL0671, a new potassium channel opener, inhibits nonenzymatic glycation of protein and LDL oxidation

1. The effects of AL0671, a novel potassium channel opener, on protein glycation and low-density lipoprotein (LDL) oxidation were tested. 2. AL0671 dose-dependently inhibited both fluorescence development of bovine serum albumin and cross-linking of lysozyme. These inhibitory effects for glycation were no less potent than aminoguanidine. 3. AL0671 dose-dependently inhibited both increase in negative charge and apo B-100 fragmentation during incubation of LDL with Cu2+. In addition, AL0671 significantly decreased the LDL degradation in rat peritoneal macrophages. 4. Neither pinacidil nor levcromakalim inhibited protein glycation and LDL oxidation. 5. Antioxidant properties of AL0671 might be due to its potent electron-donating ability, and this agent is expected to be useful for hypertensive diabetes.

MRI OF EARLY OSTEONECROSIS OF THE FEMORAL HEAD AFTER TRANSCERVICAL FRACTURE

We have carried out a prospective study of 17 patients (14 women, 3 men) of mean age 48 years (21 to 76) with transcervical fractures of the femur using MRI to detect early evidence of avascular necrosis of the head.

Two fractures were Garden stage I, 12 stage II, and three stage III. We performed internal fixation under radiological control at a mean of five days (2 to 15) after injury using a titanium cannulated cancellous screw or a titanium compression hip screw. MRI was performed at one, six and 12 months and then yearly after operation. T1- and T2-weighted images were obtained by a spin-echo technique. The duration of follow-up of patients who did not subsequently require replacement of the head of the femur was from 2 to 5 years (mean 3.2).

One month after operation eight of the 17 hips showed a band of low signal intensity on T1-weighted images and high signal intensity on T2-weighted images indicating lesions in the femoral head away from the fracture line. These were of three types: type I was a small infarct at the superolateral region of the femoral head and was seen in three hips; type II was a shallow lesion from the superolateral region to the fovea of the femoral head (three hips); and type III was a large lesion occupying most of the femoral head (two hips). No further changes were seen in the MRI after six months from operation. Collapse of the femoral head did not occur in the three hips with type-I lesions, but two of the three type-II hips and both type-III hips subsequently collapsed. At the final follow-up the three hips with a type-I lesion and one with a type-II were still asymptomatic but radiography showed sclerosis in the femoral head corresponding to the MRI lesions. The nine hips which showed no changes on MRI at one month had no abnormal findings on physical examination, radiography or MRI at final follow-up.

Apoptosis in human hepatoma cell line induced by 4,5-didehydro geranylgeranoic acid (acyclic retinoid) via down-regulation of transforming growth factor-alpha

Synthetic 4,5-didehydro GGA (geranylgeranoic acid), a potent ligand both for cellular retinoic acid-binding protein and for nuclear retinoid receptors, induced apoptosis in human hepatoma-derived cell line HuH-7 but not in primary hepatocytes, although all-trans or 9-cis retinoic acid did not induce any growth inhibition. Either exogenous transforming growth factor-alpha (TGF alpha) or epidermal growth factor(EGF) prevented the cells from apoptosis in the presence of 4,5-didehydro GGA, but hepatocyte growth factor, insulin-like growth factor-II, insulin or triiodothyronine was essentially inactive. 4,5-Didehydro GGA down-regulated the cellular levels of TGF alpha mRNA as early as 30 min after the treatment. Either anti-TGF alpha or anti-EGF receptor monoclonal antibody induced apoptosis in HuH-7 cells without using the acid. Taken together, the present study strongly suggests that 4,5-didehydro GGA induced apoptosis in HuH-7 cells through the destruction of autocrine loop consisting of TGF alpha and EGF receptor, due to the down regulation of TGF alpha gene expression.

Screening for bacteria producing sucrose phosphorylase and characterization of the enzymes

Two microbial strains, No. 165 and No. 168, were isolated from soil as sucrose phosphorylase producers and identified as Leuconostoc mesenteroides subsp. mesenteroides and subsp. dextranicum, respectively. The sucrose phosphorylases were purified, characterized, and compared with the enzymes of L. mesenteroides AKU1102 and ATCC12291. As for the catalytic properties, these enzymes were close to each other, while as for the enzyme molecules, the No. 165 enzyme (Mr: 58,000) was slightly different from the other (Mr: 54,000), though their N-terminal amino acid sequences were almost the same.

Synthesis and pharmacological evaluation of N-(6-functionalized-amino-3-pyridyl)-N'-bicycloalkyl-N''-cyanoguanidine s as antihypertensive agents

A series of amino acid conjugates of N-(6-amino-3-pyridyl)-N'-[exo-bicyclo[2.2.1]hept-2-yl]-N''- cyanoguanidine (4) were prepared and evaluated as antihypertensive agents. The parent compound 4 showed potent potassium channel-opening and antihypertensive activities, but with undesirable changes of the urinary balance of electrolytes. However, alanine and histidine congeners (9,19) reduced this undesirable side effect of 4 through improved pharmacokinetics without loss of antihypertensive activity. They also provided additional information on the structural requirements for pinacidil-type potassium channel openers.

Cloning and expression in Escherichia coli of sucrose phosphorylase gene from Leuconostoc mesenteroides No. 165

The sucrose phosphorylase gene of an isolate, Leuconostoc mesenteroides No. 165, was amplified by PCR, cloned on pUC118, and expressed in E. coli. The nucleotide sequence of the gene showed 96.3% similarity to that of L. mesenteroides ATCC12291 and 67% to that of Streptococcus mutans, but low similarity to the Agrobacterium vitis gene. The cloned gene, which fusing with lacZalpha, was expressed inducibly with IPTG in E. coli to produce an active enzyme in large quantities that accounted for about 50% of the total cell protein.

The relationship between the gene mutation of p53 and the protein expression of p53 and Ki-67 in non-Hodgkin's lymphomas

The relationship between the mutation of the p53 gene and the expression of the p53 protein and the Ki-67 antigen has been investigated in 115 cases with non-Hodgkin's lymphoma, using the immunohistochemical double staining technique, single-strand conformational polymorphism and DNA sequencing methods. Eighteen cases showed more than 10% of p53+ cells and the others showed a few p53+ cells presented sporadically. Alterations in the p53 gene were detected in six cases with B cell type, consisting of five cases with point mutation and one case with point mutation and 15 base pairs deletion. These six cases showed a high percentage of p53+ cells and five cases revealed that the percentage of p53+ cells was higher than that of Ki-67+ cells (p53+ cells > Ki-67+ cells). Excluding the six cases with mutation of the p53 gene, all cases revealed that the percentage of p53+ cells was less than that of Ki-67+ cells (p53+ cells < Ki-67+ cells). Moreover, there was a positive correlation between expression of the p53 protein and of the Ki-67 antigen in histologic types of B cell lymphomas and of T cell lymphomas, respectively, except in small non-cleaved (Burkitt's) and lymphoblastic types. Therefore, sporadic cases showing p53+ cells > Ki-67+ cells revealed alteration of the p53 gene, and expressed abnormal p53 protein (mutant form). Most cases showing p53+ cells < Ki-67+ cells expressed normal p53 protein (wild type), and may reflect the rapid proliferation rate.

Glyoxal oxidase from Phanerochaete chrysosporium is a new radical-copper oxidase

A free radical-coupled copper complex has been identified as the catalytic structure in the active site of glyoxal oxidase from Phanerochaete chrysosporium based on a combination of spectroscopic and biochemical studies. The native (inactive) enzyme is activated by oxidants leading to the elimination of the cupric EPR signal consistent with formation of an antiferromagnetically coupled radical-copper complex. Oxidation also leads to the appearance of a substoichiometric free radical EPR signal with an average g value (gav = 2.0055) characteristic of phenoxyl tau-radicals arising from a minority apoenzyme fraction. Optical absorption, CD, and spectroelectrochemical measurements on the active enzyme reveal complex spectra extending into the near IR and define the redox potential for radical formation (E 1/2 = 0.64 V versus NHE, pH 7.0). Resonance Raman spectra have identified the signature of a modified (cysteinyl-tyrosine) phenoxyl in the vibrational spectra of the active complex. This radical-copper motif has previously been found only in galactose oxidase, with which glyoxal oxidase shares many properties despite lacking obvious sequence identity, and catalyzing a distinct reaction. The enzymes thus represent members of a growing class of free radical metalloenzymes based on the radical-copper catalytic motif and appear to represent functional variants that have evolved to distinct catalytic roles.

[Evaluation of area at risk by 123I-BMIPP in patients with acute myocardial infarction]

The purpose of this study was to investigate the detection of area at risk of acute myocardial infarction (AMI) by 123I-BMIPP (BMIPP). 99mTc-tetrofosmin (TF) scintigraphy was performed on 13 patients with AMI with total coronary occlusion. BMIPP scintigraphy was done on the same patients within 1 week after successful reperfusion by direct PTCA. Activity of both tracers was scored in 8 basal, 8 midventricular and 2 apical segments, using a four-point grading system as defect score: 3 = defect, 2 = severely low uptake, 1 = slightly low uptake, 0 = normal. Extent score (ES) was defined as a total number of segment which deteriorated of uptake, and severity score (SS) was defined as a total score of defect score. ES of BMIPP was 6.5 +/- 2.4 and that of TF was 7.5 +/- 2.4. ES of BMIPP was smaller than that of TF. A ratio of BMIPP/TF was 0.86 +/- 0.18. SS of BMIPP was 16.2 +/- 6.0 and that of TF was 19.2 +/- 5.6. SS of TF was larger than that of BMIPP. A ratio of BMIPP/TF was 0.83 +/- 0.18. A correlation of ES and SS between TF and BMIPP was excellent. BMIPP showed ischemic area by culprit lesion and infarct area clearly. We concluded that BMIPP could indicate area at risk.