[Total arch replacement for dissecting aneurysm using permanent bypass to the supra-aortic branches and left-heart bypass]

The patient was a 36-year-old women with Marfan syndrome who had received graft replacement of ascending aorta for Stanford-type A dissecting aneurysm two years ago. She was re-operated on for residual arch and descending aortic dissection. We have found that it was Simple and effective to perform total arch replacement by using permanent bypass to the three principal supra-aortic branches and left-heart bypass.

Activity of the carbapenem panipenem and role of the OprD (D2) protein in its diffusion through the Pseudomonas aeruginosa outer membrane

Evidence of permeation of panipenem through the OprD (D2) channel of Pseudomonas aeruginosa outer membrane was shown by using OprD protein-producing and -nonproducing strains which contained plasmid pHN4, which codes for L-1 beta-lactamase of Xanthomonas maltophilia. Permeation by panipenem was determined by measuring hydrolysis of the carbapenem by beta-lactamase in the periplasmic space. Permeation by panipenem was also determined by counting uptake of [14C]panipenem into P. aeruginosa PAO1 and its OprD protein-deficient mutant, and this permeation of PAO1 was inhibited by L-lysine. These results indicate that panipenem, as well as imipenem, uses the OprD channel, which functions as a specific channel for diffusion of basic amino acids. Panipenem and imipenem showed stronger activities against PAO1 and clinical isolates in human serum than in Mueller-Hinton broth, which contains more amino acids than human serum does. The activities of the carbapenems were reduced by addition of L-lysine to human serum. Similar results were obtained with mouse serum and ascitic fluid. In contrast, such a change in the activities of carbapenems was not observed with an OprD protein-deficient mutant, suggesting that the main reason for the strong activities of carbapenems in biological fluids is a decrease in competition between the antibiotics and basic amino acids for permeation through the OprD channel. Panipenem and imipenem showed much stronger therapeutic efficacies against experimental infections with P. aeruginosa in mice than did the reference antibiotics. Their in vivo activities were more consistent with their MICs in biological fluids than with those in Mueller-Hinton broth.

Isoflavanones from the heartwood of Swartzia polyphylla and their antibacterial activity against cariogenic bacteria

The methanolic extract of Swartzia polyphylla DC. heartwood had antibacterial activity against cariogenic bacteria, the mutans Streptococci. The chromatographic purification of the extract afforded seven flavonoids. Among them, three known isoflavanones, dihydrobiochanin A, ferreirin and darbergioidin, and one new isoflavanone, 5,2',4'-trihydroxy-7-methoxyisoflavanone (dihydrocajanin) had potent antibacterial activity against cariogenic bacteria. This effect was not detected on isoflavone derivatives. A comparative antibacterial study of various flavonoids was further performed, and their structure-activity relationship was discussed.

[Aspergillosis involving the thoracic spinal cord--an autopsy case]

A 63 year old male complained of persistent backache and productive cough. The chest X-ray revealed the fungus ball at the left apical-posterior segment and Aspergillus fumigatus was cultured from the sputum. He was treated on fulconazole and miconazole. Six months later, motor and sensory paralysis below the mamillary level and urinary and stool incontinence developed. A magnetic resonance image disclosed the destruction of the second thoracic spinal vertebra involved by the cavitated fungus ball of the left lung. Continuous peroral administration of antifungal drugs was not successful, and he expired with severe dyspnea. The autopsy revealed an extensive granulomatous and purulent change of the epidural and subdural spaces of the second to fifth thoracic spinal cord. Subdural inflammation extended to the lower thoracic and lower cervical level. Thoracic spinal cord revealed an extensive myelomalacia predominantly involving the left lateral white column, and also anterior and posterior columns. Small areas of the white matter were cystic. The left anterior horn cells revealed severe central chromatolysis. Moderate lymphocytic and plasma cell infiltration was found around the vessels within the cord. A few thrombi were found in the vein near the anterior nerve root. Central nervous system involvement of pulmonary aspergillosis is quite uncommon. However, there are a few reports of patients with paraplegia secondary to the spinal extension by aspergillus infection. Sheth et al. described that epidural and subdural granulomatous change with aspergillus abscesses and spinal cord myelomalacia is comparable to metastatic carcinoma. However, the aspergillus infection in the spinal cord is more extensive and destructive.(ABSTRACT TRUNCATED AT 250 WORDS)

p13suc1 suppresses the catalytic function of p34cdc2 kinase for intermediate filament proteins, in vitro

The regulation of p34cdc2 kinase activity controls the entry into and exit from mitosis. Although genetic and biochemical evidence suggested close interactions between cyclins, p13suc1 and p34cdc2 kinase, the roles of p13suc1 on p34cdc2 kinase functions remain unclear. To examine the effects of p13suc1 on p34cdc2 kinase function we developed a simple purification procedure for p34cdc2 kinase, unassociated with p13suc1. The key to the purification procedures we used was buffer containing 0.5 M NaCl and 50% ethylene glycol, as a specific elutant of p34cdc2 kinase from p13suc1-Sepharose. This purified p34cdc2 kinase stoichiometrically phosphorylated vimentin and desmin. Exogenous p13suc1 suppressed the phosphorylation of these filament proteins by the kinase and prevented disassembly, although histone H1 phosphorylation was not affected. Peptide mapping analysis showed a similar extent of inhibition by p13suc1 for all five phosphorylation sites by p34cdc2 kinase of vimentin and desmin, hence these p13suc1-induced inhibitions are probably not site-specific. It thus appears that p13suc1 has a selective effect on the catalytic activity of p34cdc2 kinase for these filament proteins.

Relationship of cholecystectomy and detachment of the common bile duct to chronic bile duct dilation

A combination of a cholecystectomy and detachment of the supportive tissue surrounding the extrahepatic bile duct results in chronic bile duct dilation. To clarify whether this cholangiectasis is due to the detachment of the surrounding tissue or to the cholecystectomy, we have studied 4 groups of adult mongrel dogs, i.e., a control group given a sham operation (n = 20), a group given cholecystectomy (n = 20), a group that had the surrounding tissue detached from the bile duct (n = 20), and a group given both a cholecystectomy and detachment of the surrounding tissue (n = 29). On examination by cholangiography at 1, 2, 3, and 4 weeks after the initial laparotomy, no significant cholangiectasis was found in dogs subjected to either cholecystectomy alone or to detachment of the surrounding tissue alone. In contrast, in dogs subjected to a cholecystectomy combined with detachment of the bile duct, the bile duct gradually dilated, resulting in significant cholangiectasis at 4 weeks. However, the intrabiliary pressure, the residual pressure, and the actual resistance value, which are indices of a passage disturbance in the sphincter of Oddi, were normal in all 4 groups. It is therefore concluded that both the extirpation of the gallbladder, and the lack of supportive tissue surrounding the bile duct were responsible for the resulting cholangiectasis.

The studies of cell damaging and cell growth factors which induce cardiomyopathy

We demonstrated that phosphatidylinositide-specific phospholipase C (PLC) activity was greater in cardiomyopathic hamster hearts (BIO 14.6 and BIO 53.58) then in hamster controls (F1b). Inositol trisphosphate (IP3) production was markedly greater in both of the cardiomyopathic hamsters, BIO 14.6 and BIO 53.58. We have also determined the sarcoplasmic reticulum (SR) function of heart. Calcium uptake into SR markedly increased in BIO 14.6. On the other hand, it significantly decreased in BIO 53.58 compared with F1b. It is well known that IP3 stimulates calcium release from SR. In BIO 14.6, calcium release from SR stimulated by IP3 increased, but its effect decreased in BIO 53.58 compared with F1b. These results suggest that PI response may produce high intracellular calcium levels in both BIO 14.6 and BIO 53.58 myocytes. In addition, in the BIO 53.58 hamster the sarcoplasmic reticulum deteriorate in function. It was concluded from these results that a prolonged high intracellular calcium level may lead to the death of BIO 53.58 myocytes. The expression of angiotensinogen mRNA was observed in the hamster heart. There was no differences in its expression level between F1b, BIO 14.6 and BIO 53.58. There was no effect of ages on its expression in these hamster hearts. We have also determined the distribution of angiotensinogen in these hamsters. At 4 weeks of age, the immunohistochemical study revealed that angiotensinogen was widely distributed in subendocardium in these hamsters. There was no difference in its distribution between F1b, BIO 14.6 and BIO 53.58. But at 20 weeks old of age its immunoreactivity decreased in BIO 53.58.(ABSTRACT TRUNCATED AT 250 WORDS)

Regulation of gene expression of proteasomes (multi-protease complexes) during growth and differentiation of human hematopoietic cells

We have reported that proteasomes are expressed at abnormally high levels in various hematopoietic tumor cells (Kumatori, A., Tanaka, K., Inamura, N., Sone, S., Ogura, T., Matsumoto, T., Tachikawa, T., Shin, S., and Ichihara, A. (1990) Proc. Natl. Acad. Sci. U.S.A. 87, 7071-7075). In the present study, we examined changes in the expressions of proteasomes during growth of peripheral T-lymphocytes from healthy adults and differentiation of human leukemic cell lines. Up-regulation of mRNAs encoding multiple proteasome subunits was observed during proliferation of resting T-cells induced by mitogens such as phytohemagglutinin and interleukin-2. In contrast, in vitro terminal differentiation into monocytic, granulocytic, and erythroid cells of various immature leukemic cell lines, such as HL-60 promyelocytic leukemia cells and K562 erythroleukemia cells, by various inducing agents caused rapid and marked down-regulation of proteasomes expression, independently of the cell type, direction of differentiation, or type of signal. The syntheses of proteasome subunits of 21-31 kDa and their associated components of 35-110 kDa, measured by [35S]methionine incorporation, were much higher in mitogen-activated T-cells and unstimulated HL-60 cells, which grow rapidly, than in resting and differentiated cells, indicating apparent correlations of the mRNA levels of proteasomes with their translational activities. However, immunochemically, no detectable difference in the cellular contents of proteasomes was found in these cells in induced and uninduced states for proliferation and differentiation, suggesting accelerated turnover of proteasomes in rapidly proliferating cells. Inhibition of proteasome expression by an antisense oligodeoxynucleotide for the largest proteasome subunit, C2, caused partial arrest of cell cycle progression of T-lymphocytes, suggesting that up-regulation of proteasomes is indispensable for proliferation of the cells. We also observed that the nuclear fraction of proteasomes increased in proliferating T-cells and that proteasomes moved rapidly between the nucleus and cytoplasm during differentiation of HL-60 cells.

Cyclin-dependent kinase 2 (cdk2) in the murine Cdc2 kinase TS mutant

Kinases of the mammalian cdc2 family including cdk2 (cyclin-dependent kinase 2) are thought to be involved in both the G2/M transition and DNA replication. To investigate the role of cdc2 kinase and cdk2 in cell cycle progression, murine tsFT210 cells bearing a temperature-sensitive cdc2 mutation were used. These kinases were purified by column chromatography, using a peptide with the consensus phosphorylation site of cdc2 kinase as the substrate. In this mutant, cdc2 kinase activity was temperature sensitive and cdk2 activity was not. At the restrictive temperature, the mutant was only arrested in the G2 phase and not in the G1-S phase, suggesting that cdk2 did not compensate for cdc2 kinase at the G2/M transition but did function at the G1-S phase. This suggestion was supported by the finding that transfection of cdk2 cDNA did not improve the growth of the mutant cell line at the restrictive temperature, although transfection of cdc2 cDNA did.

Preference of human cdc2 kinase for peptide substrate

Human cyclin B1-bound cdc2 kinase phosphorylated the threonine residue in the sequence -Thr-Pro-Lys-Lys-Ala- but hardly phosphorylated it in the sequence -Thr-Pro-Lys-Ala-Lys. The sequence -Thr-Pro-Ala-Pro-Lys-, as found in p53 protein, was also phosphorylated by this enzyme, but less efficiently than in the sequence described above. When the threonine residue in -Thr-Pro-Lys-Lys-Ala- was changed to a serine or a tyrosine residue, the enzyme phosphorylated the serine, but not the tyrosine residue. Changing the lysine next to the proline to alanine reduced its efficiency as a substrate. The peptide, Ala-Ala-Ala-Ala-Lys-Thr-Pro-Ala-Lys-Ala-Ala, containing the -Thr-Pro-Ala-Lys- sequence, but not the other lysine residues, was not used as a substrate by the kinase.

The role of calcium activated neutral protease on myocardial cell injury in hypoxia

The aim of this study was to investigate the correlation between hypoxic myocardial cell injury and intracellular protease activity. Cardiac myocytes were isolated from neonatal rat hearts and cultured in Eagle's modified minimum essential medium. Myocytes were incubated in hypoxic conditions for 6 hours. The cell death rate during hypoxia rose to 80% after 6 hours. Extracellular protease activity was elevated to 4 units during hypoxia, much higher than the 0.7 units in aerobic states at 6 hours. This extracellular protease activity in hypoxic conditions was markedly inhibited by leupeptin and EDTA, and weakly inhibited by the cysteine protease inhibitor, NCO-700, but phenylmethyl sulfonyl fluoride did not inhibit the protease activity. To identify the protease activated during hypoxia, calpain-specific inhibitors were added to the incubation mixture. Calpain inhibitor 1 and calpastatin, an endogenous selective calpain inhibitor, markedly inhibited extracellular protease activity during hypoxia. NCO-700 also inhibited intracellular protease activity. NCO-700 reduced hypoxic cell death to 30% after 6 hours of hypoxygenation. These observations indicate that calpain is activated during hypoxia and leads to irreversible cell membrane degradation after 6 hours of hypoxygenation.

The cell cycle regulator, human p50weel, is a tyrosine kinase and not a serine/tyrosine kinase

The human weel protein, a homologue of the yeast weel protein, was expressed in E. coli and purified to homogeneity. The purified weel protein phosphorylated the tyrosine residue of cdc2 kinase in HeLa cell extracts in the presence of human cyclin B1. It also phosphorylated the tyrosine but not the threonine residue in the peptide of the amino-terminal of cdc2 kinase, although both these residues have been shown to be phosphorylated in higher eukaryotes in vivo. Furthermore, serine and tyrosine residues of the yeast weel protein are reportedly autophosphorylated in vitro, however the tyrosine residue of the human weel protein was autophosphorylated whereas the serine and threonine residues were not. These data indicate that human p50weel is tyrosine kinase and that it phosphorylated the tyrosine residue of the amino-terminal of cdc2 kinase in the presence of cyclin B1 and that the threonine residue is phosphorylated by another, unknown kinase.

Familial spinal xanthomatosis with sitosterolemia

A family with multiple spinal xanthomas and sitosterolemia is described. A 48-year-old woman presented with paraplegia due to multiple intradural extramedullary tumors. The patient also showed marked tendon xanthomas and analysis of sterol composition in both plasma and the xanthoma established the diagnosis of the rare inherited metabolic disease, sitosterolemia and xanthomatosis. Two other siblings in the family presented with marked tendon xanthomas and coronary atherosclerosis, but did not show any neurological signs or symptoms. Magnetic resonance imaging (MRI) study revealed multiple intradural extramedullary tumors in spinal canals of the proband and her sister, but not in the other affected sibling (brother). This is the first report of familial occurrence of multiple extramedullary spinal tumors due to the inherited metabolic abnormality.

Differential occurrence of CSF-like activity and transforming activity of Mos during the cell cycle in fibroblasts

The Xenopus c-mos proto-oncogene product, Mosxe, possesses cytostatic factor (CSF) activity to arrest maturing oocytes in metaphase II and has weak transforming activity in mouse NIH3T3 cells. We show that Mosxe mutants bearing 'stabilizing' penultimate N-terminal amino acids are strongly transforming and can retard progression through the G2-M phases in Mosxe-transformed cells, probably via their CSF activity. On the other hand, a cyclin-Mosxe fusion protein, which undergoes abrupt degradation at the end of mitosis and is restored to its normal levels only after the G1 phase, transforms cells much less efficiently than a mutated cyclin-Mosxe fusion protein that is stable during M-G1 transition. Moreover, in low-serum medium, cells transformed by the unstable cyclin-Mosxe require a long period to enter the S phase, in contrast with the rapid entry into the S phase of cells transformed by the stable cyclin-Mosxe. These results provide strong evidence that unlike the physiological CSF activity, the transforming activity of Mos is exerted in the G1 phase of the cell cycle.

Expression of the angiotensinogen gene and localization of its protein in the human heart

BACKGROUND

There have been no reports on the presence of the tissue renin-angiotensin system in the human heart, although the presence of angiotensinogen has been described in the animal heart.

METHODS AND RESULTS

To determine whether angiotensinogen is synthesized in the human heart, we examined angiotensinogen messenger RNA (mRNA) synthesis in autopsy hearts by using ribonuclease protection assay. As a result, angiotensinogen mRNA was detected in the atrial muscle, muscles of the conduction system, and the left ventricular wall. In the left ventricular wall, mRNA expression was more prominent in the subendocardial muscles than in the midcardial or epicardial muscles. Using a monoclonal antibody to human angiotensinogen in immunoblotting experiments, we detected two closely spaced bands at approximately 70 kd in the heart, which was quite consistent with the human angiotensinogen molecule. Immunohistochemical studies with this monoclonal antibody demonstrated intense immunoreactivity in the atrial muscles, the muscles of the conduction system, and those of the subendocardial layers.

CONCLUSIONS

We conclude that angiotensinogen was synthesized in the human heart. It was evident that the localization of angiotensinogen was not ubiquitous in the cardiac muscles, showing its predilection for the atrial muscles, muscles of the conduction system, and subendocardial layer of the left ventricle.