[A case of total arch replacement for redissected impending rupture of early thrombosed aortic dissection without intimal tear detectable at operation]

A 51-year-old suddenly developed severe chest and back pains. The diagnosis was acute aortic dissection of Stanford type A, but the dissecting space was not observed by enhanced CT scan. Medical treatment was started as early thrombosed aortic dissection. The blood pressure was sufficiently controlled, and the symptom was gradually improved. On the 8th hospital day, a severe chest pain appeared again, Enhanced CT scan showed an enlarged dissecting space, pericardial and pleural effusion. These findings were considered a redissected impending rupture, so the emergency operation was performed. Fresh clots were observed in the dissecting space of ascending aorta, but the intimal tear was not found in any portion of the examined aorta. Therefore total arch replacement was needed to resect the wall which may be responsible for the dissection and to reduce the residual dissecting space. The patient recovered without complications. Postoperative CT scan revealed no residual false lumen in the distal descending aorta.

[Talc pulmonary granulomatosis caused by intravenous administration of methylphenidate]

A 57-year-old man was admitted with fever and a dry cough in 1985. He had used methylphenidate intravenously for 3 years. A chest X-ray film on admission showed diffuse micronodular shadows and massive lesions in the lower lung fields bilaterally. Pulmonary granulomatosis was diagnosed histologically, but the etiology remained unclear. In 1993, the patient was readmitted because of symptom exacerbation. The micronodular shadows had extended and the bilateral, massive lesions had enlarged. Transbronchial lung biopsy revealed granulomas with crystallized foreign bodies. Electron microscopy confirmed that the foreign bodies consisted of magnesium and silicon, suggesting talc. Talc granulomatosis caused by intravenous administration of methylphenidate was subsequently diagnosed. The symptoms improved with conservative treatment, and no signs of reexacerbation have appeared.

[Current status and problems of home parenteral nutrition for terminal cancer patients from the viewpoint of indication]

Since June 1993, we have been performing home parenteral nutrition (HPN) for end-stage cancer patients. We studied how many patients could be treated with HPN, why they were not able to be treated with HPN in the terminal stage cancer patients, 158 cases, who admitted and died in our ward from June 1993 to April 1997. Eighty-six patients (54.4%) were considered to not be indicated for HPN, due to general weakness (28 cases), dyspnea (17 cases), need for medical care other than HPN (34 cases), and inability to understand this treatment (1 case). Fifty-six patients (35.4%) were considered to have been able to be treated with HPN and could have had returned home. Fifteen patients (26.8%) were given HPN. Four cases wanted to stay in the hospital after they knew the truth and the prognosis of their disease. Another four patients became weak while preparing for HPN and could not go home. Eighty percent of patients could not to be treated with HPN because of the factors of their family. Eight patients had no family to cared for them. Twelve patients were refused to the truth of their disease. The families of 13 cases refused to accept and care for them in their home. We may conclude that co-operation among patients, their family and the medical staff is the most important factor in providing HPN for end-stage cancer patients.

[Sequence variability in Borna disease virus ORF II from human beings]

40 clones from five psychiatric patients and three healthy blood donors in whom Borna disease virus (BDV) ORF II fragments in PBMC were previously proved by nested RT-PCR were sequenced and compared with BDV/MDCK. There were eleven point mutations in all clones compared with reported HE80-1, but no difference between human and BDV/MDCK clones. We found specific sequence variability at nt 1701 in ten clones from two psychiatric disorder patients (T-->C) and at nt 1696 in fifteen clones from three healthy blood donors (A-->T). This result strongly suggests there are some special gene divergence in BDV derived from human beings.

Left midcardiac border of frontal chest radiographs of patients with annulo-aortic ectasia

The utility of the frontal chest radiograph for the diagnosis of annulo-aortic ectasia (AAE) was evaluated in 12 patients with Marfan's syndrome and five patients with incomplete stigmata (forme fruste). Prominence of the left midcardiac border was seen in 11 patients: the upper midsegment in one, the lower midsegment in two, and the whole midsegment in eight patients. Either a linear or an arcuate contour was seen. The contours of the prominent left midcardiac border in three patients who had moderate to marked aortic regurgitation and a cardiothoracic ratio (CTR) over 59% were nonspecific. In the remaining eight patients (47%), the contour was considered to be characteristic of AAE, as suggested by the displacement of either all or part of the right ventricular outflow tract, main pulmonary artery and left atrial appendage. Six patients showed only left midcardiac border prominence. The contour of the left midcardiac border on the conventional frontal chest radiograph is characteristic and of paramount importance for the diagnosis of AAE in Marfan' s syndrome or its forme fruste, particularly in patients whose CTRs are within the normal range.

Characterization of Ret-Shc-Grb2 complex induced by GDNF, MEN 2A, and MEN 2B mutations

We analyzed the intracellular signalling pathway through Ret activated by glial-cell-line-derived neurotrophic factor (GDNF), multiple endocrine neoplasia (MEN) 2A and 2B mutations. The results showed that all of them induce a signal transducing complex consisting of Ret, Shc, and Grb2 proteins. In addition, GDNF clearly activated a Ras-MAPK pathway in human neuroblastoma cells. Rat is expressed mainly as two isoforms that differ in the carboxy-terminal sequence: a long isoform (1114 amino acids) and a short isoform (1072 amino acids). The long isoform contains the consensus sequence for binding of the Shc PTB domain but not of its SH2 domain, whereas the short isoform has the consensus sequences for binding of both domains. In vitro binding assay revealed that the long isoform of the MEN2A-Ret protein and both isoforms of the MEN2B-Ret protein bound preferentially to the Shc PTB domain. On the other hand, the short isoform of MEN2A-Ret bound to the PTB and SH2 domains. In neuroblastoma cells expressing both isoforms of Ret, its activation by GDNF also resulted in the binding of both domains. GDNF and MEN 2A mutations activate Ret by inducing its dimerization, whereas the MEN 2B mutation increases Ret catalytic activity without dimerization. Our results thus suggest that Ret dimerization might be required for binding of the Shc SH2 domain to the short isoform.

Biological properties of Ret with cysteine mutations correlate with multiple endocrine neoplasia type 2A, familial medullary thyroid carcinoma, and Hirschsprung's disease phenotype

We investigated the transforming activity of the ret proto-oncogene with a mutation in cysteine 609, 611, 618, 620, 630, or 634 detected in patients with multiple endocrine neoplasia type 2A (MEN 2A), familial medullary thyroid carcinoma (FMTC), or Hirschsprung's disease. Of these cysteine mutations, codon 634 mutations are known to be correlated with the development of MEN 2A, whereas codon 609, 618, or 620 mutations were detected in two-thirds of FMTCs and in several cases of Hirschsprung's disease. Analysis of a total of 18 mutant genes revealed that codon 634 mutations have the highest transforming activity. The activity of ret with a codon 609, 611, 618, or 620 mutation and with a codon 630 mutation was approximately 3- to 5-fold and 2-fold lower than that of ret with a codon 634 mutation, respectively. In addition, different amino acid substitutions for the same cysteine displayed comparable transforming activity. The expression of the cell surface form of Ret with codon 609, 611, 618, or 620 mutation was very low compared with that of Ret with codon 634 mutation, indicating that the former four mutations might impair transport of Ret to the plasma membrane, as observed for several Hirschsprung mutations affecting the Ret extracellular domain. These results thus suggest that mutations in cysteine 609, 611, 618, or 620 may have the potential to develop Hirschsprung's disease in addition to MEN 2A and FMTC.

Expression of matrix metalloproteinase (gelatinase) in T1 adenocarcinoma of the lung

The expression of matrix metalloproteinase-2 (MMP-2; 72 kDa type IV collagenase/gelatinase A) and MMP-9 (92 kDa type IV collagenase/gelatinase B) was immunohistochemically investigated in 79 T1 adenocarcinomas of the lung using non-commercial polyclonal anti-MMP-2 and -9 antibodies. Thirty-two (41%) and 22 (28%) among the 79 cases were positive in the tumor cells for MMP-2 and -9, respectively. The incidences of MMP-2 and -9 immunoreactivities were higher (64 and 45%, respectively) in poorly differentiated tumors than in well differentiated tumors (36 and 25%, respectively), and lower in bronchioloalveolar carcinoma (22 and 10%, respectively) compared with other subtypes of adenocarcinoma. The prognosis for patients with MMP-2 and/or -9 positive immunoreactivities was significantly poorer than for those with a MMP-negative tumor (P < 0.05). The degree of collagenization was divided into four grades, and tumors with a small to abundant amount of collagen (grade 2 and grade 3 fibrosis) had a higher incidence of immunoreactivity to both types of MMP. It is estimated that these expressions might be responsible for tumor invasion, metastasis, and for grade 2 and grade 3 fibrosis in T1 adenocarcinoma of the lung.

[CABG performed for LMT orifice stenosis 15 years after AVR in a case of aortitis syndrome]

The case is a 54-year-old female at age 39 years, she underwent aortic valve replacement (AVR) for aortic valve regurgitation (AR) due to aortitis syndrome at a certain hospital. At the 15th year after AVR she was diagnosed with unstable angina due to LMT orifice stenosis and underwent CABG at this hospital. A distal side of anastomosis was performed on the LAD branch seg 6, an artificial vascular patch was placed for the proximal side of anastomosis to prevent inflammation of the aortic wall from spreading to the proximal side of anastomosis. On the postoperative cardiac catheter examination, the graft was found to be patent well. In the case of CABG complicated with aortitis syndrome, stenosis and obstruction of the proximal side of anastomosis long time after surgery pose a problem. However, the method so as to perform a proximal anastomosis by placing an artificial vascular patch on the aortic wall is considered to be one of the useful means which can avoid such a problem.

Macrophage cathepsin L, a factor in the erosion of subchondral bone in rheumatoid arthritis

OBJECTIVE

To test the hypothesis that the proteinase cathepsin L is involved in the subchondral bone lesions found in chronic rheumatoid arthritis (RA).

METHODS

The medial tibial plateaus from 4 control cases and 30 patients diagnosed as having end-stage RA were examined immunochemically for cathepsin L.

RESULTS

RA lesions include large groups of mononuclear cells, many of which are rich in cathepsin L. Since these mononuclear cells contained the CD68 glycoprotein and, in the electron microscope, displayed an irregular cell surface, cytoplasmic vacuoles, lysosomes, and phagosomes, they were identified as belonging to the macrophage family. The lesions were classified into 2 main patterns, both displaying these cathepsin L-rich cells, which, in at least 1 of the 2, were closely associated with bone degradation.

CONCLUSION

The cathepsin L-rich macrophages are sufficiently numerous to be considered a major factor in producing the erosion of subchondral bone found in chronic RA lesions.

mRNA expression and cDNA sequences of beta- and gamma-sarcoglycans are normal in cardiomyopathic hamster heart

In BIO14.6 cardiomyopathic hamster heart, the dystrophin-glycoprotein complex is disrupted and sarcoglycans are greatly reduced in abundance. We examined whether the gene expression of beta- and gamma-sarcoglycans is indeed defective in this hamster. We found that mRNA expression for these proteins and the cDNA sequences of their coding regions are identical in both normal and myopathic hamster cardiomyocytes. The results strongly suggest that defect in a currently unknown sarcoglycan-associated protein(s) is responsible for the deficiency of the sarcoglycan complex that leads to muscle cell necrosis in the myopathic hamster.

Reconstruction of the 3D coordinates of alpha-carbon atoms of proteins from a pair of stereographic figures

In an attempt to promptly use the experimentally determined structures of proteins in modeling studies, we have developed the program ReconstC alpha to generate the 3D coordinates of alpha-carbon atoms from a pair of stereographic figures. Calculations of the 3D coordinates were performed by estimating the stereo parameters systematically. Geometrical features of C alpha traces were used to evaluate the integrity of the calculated structure. The program was applied to four kinds of protein structures to examine the performance. It was found that the root-mean-square deviation of atomic positions between constructed and reference crystal structures ranged from 0.36 to 0.78 A. The range represents a reasonable accuracy and its automatic feature suggests that our approach would be expedient for providing initial structures for protein modeling studies.

Hepatic embolization through extrahepatic collateral pathways after hepatic arterial embolization for the hepatocellular carcinoma

Extrahepatic collateral pathways developing after repeated transcatheter arterial embolization (TAE) for hepatocellular carcinoma (HCC) make therapeutic arterial embolization for recurrent lesions extremely difficult. TAE was performed through the collateral pathways using a sophisticated micro-catheter with good trackability and pushability and a coaxial system. Twenty-three TAEs were undertaken through the collateral pathways in 13 patients with recurrent HCC who had extrahepatic collateral pathways after the previous hepatic arterial TAE. There were 69 extrahepatic collateral pathways, with partially obstructed hepatic arteries. On the average, three feeding arteries were seen in the liver. The main extrahepatic collateral pathways were the inferior phrenic artery and epicholedocal artery, 18 vessels and 29 vessels, respectively, accounting for about 80% of the total collateral pathways. TAEs were successful in all cases and the number of embolized vessels was 2.1 on average. The average time of the first collateral TAE after the initial conventional hepatic arterial TAE was 2.3 years. Excellent prognosis was observed with a one-year survival rate of 77% and 3-year survival rate of 38% after the collateral TAE. We consider that collateral TAE for recurrent HCC with obstruction of the hepatic artery is the procedure of choice, is technically feasible, and provides better prognosis for the patients.

Dystrophin-glycoprotein complex purified from hamster cardiac muscle. Comparison of the complexes from cardiac and skeletal muscles of hamster and rabbit

The dystrophin-glycoprotein complex was isolated from hamster ventricular muscle by a method involving homogenization of muscle directly in the presence of 1% digitonin, followed by chromatography on succinylated wheat germ agglutinin agarose, Diethyl aminoethyl (DEAE) cellulose, and/or immunoaffinity agarose. Protein yield of the DEAE cellulose-purified dystrophin-glycoprotein complex was 120 +/- 30 (n = 3) micrograms per 5 g hamster ventricular muscle. The cardiac dystrophin-glycoprotein complex, unlike the skeletal muscle counterpart, could not be solubilized from a microsomal fraction with digitonin or some other detergents. By sodium dodecyl sulfate gel electrophoresis, protein composition of the dystrophin-glycoprotein complexes from hamster cardiac muscle was found to be significantly different from that of rabbit skeletal muscle which has been extensively studied. This difference mainly arises from the species difference, because in hamster the cardiac and skeletal muscle complexes exhibited essentially the same protein composition. In rabbit, on the other hand, there are differences between the cardiac and skeletal complexes in the relative abundance of 60 and 64 kDa proteins and in the apparent M(r) of alpha-dystroglycan. We found that the content of the dystrophin-glycoprotein complex, estimated by quantitative immunoblot assay, is at least 5 times more abundant in cardiac than in skeletal muscle in hamster and rabbit.

Small-vessel radiography in situ with monochromatic synchrotron radiation

PURPOSE

To evaluate the usefulness of a radiographic system with monochromatic synchrotron radiation to depict small vessels and peripheral secretory ducts.

MATERIALS AND METHODS

Radiography of various organs was tested in 14 anesthetized dogs and pancreatography was performed in an excised human pancreas by using the following system: monochromatic synchrotron radiation with an energy level just above the k absorption edge of iodine as an x-ray source and a high-definition TV system with a high-light-sensitivity image pick-up tube camera coupled with a fluorescent screen as a detector.

RESULTS

This system allowed depiction of small vessels (diameter < 50-100 microns) of the heart (penetrating transmural artery), brain (perforating arteries that arise directly in the circle of Willis), and intestinal organs (vasa recta and their submucosal communications) and of small branches (down to the fifth order) of the pancreatic duct.

CONCLUSION

The synchrotron radiation system may be useful for evaluating microcirculatory disorders and early-stage malignant tumors in various human organs.

C-Myc and Bcl-2 protein expression during the induction of apoptosis and differentiation in TNF alpha-treated HL-60 cells

We examined c-Myc and Bcl-2 protein expressions during the induction of apoptosis and differentiation in TNF alpha-treated HL-60 cells using a two-color flow cytometric method. We found that c-Myc protein was rapidly down-regulated in the apoptotic cells while Bcl-2 protein was expressed at relatively high levels. Concomitantly with terminal differentiation Bcl-2 protein was down-regulated in differentiating cells as well as c-Myc protein. We also showed that c-myc antisense oligonucleotides could induce apoptosis in HL-60 cells whereas bcl-2 antisense did not induce apoptosis during the early time of treatment. These results suggest that the down-regulation of c-Myc protein expression is a primary event to induce apoptosis and neither consistent expression of c-Myc protein nor rapid down-regulation of Bcl-2 protein is necessary for the initial processing of apoptosis in HL-60 cells. Furthermore, concomitant down-regulation of c-Myc and Bcl-2 is closely associated with terminal differentiation and apoptotic cell death of HL-60 cells treated with TNF alpha.

A RING finger motif regulates transforming activity of the rfp/ret fusion gene

The rfp/ret transforming gene was generated by DNA rearrangement which occurred during transfection of NIH 3T3 cells. The amino-terminal half of Rfp with a RING finger motif was fused to the truncated Ret receptor tyrosine kinase, leading to a transforming sequence, Rfp/Ret. In the present study, to elucidate the importance of a RING finger motif for its transforming activity, we mutated cysteine or histidine residues present in the motif that are believed to be crucial for the tertiary structure of the protein. Substitution of Cys-16, Cys-31, or His-33 markedly decreased the transforming activity of Rfp/Ret. These mutations also resulted in a striking decrease of tyrosine phosphorylation of the mutant proteins in transfectants. In contrast, mutations of Cys-118 or His-124 in the second cysteine/histidine-rich motif (called B box) of Rfp/Ret did not affect its activity. These results thus indicated that the RING finger structure is critical for the full transforming activity of Rfp/Ret.

Expression of a dystrophin-sarcoglycan complex in serum-deprived BC3H1 cells and involvement of alpha-sarcoglycan in substrate attachment

Dystrophin and alpha- and gamma-sarcoglycans were newly expressed in BC3H1 cells during differentiation induced by serum withdrawal. These proteins formed a tight complex with other dystophin-associated proteins (DAPs), as detected by immunoprecipitation with anti-dystrophin antibody. Integrins beta 1 and beta 3, vinculin, and focal adhesion kinase were also detected in the same immunoprecipitate. In a cell adhesion assay, differentiated BC3H1 cells attached more efficiently to type I collagen-coated dishes than nondifferentiated cells and loss of alpha-sarcoglycan induced by antisense ODN in differentiated cells resulted in significant inhibition of cell adhesion. Thus dystrophin and DAPs, at least partly, form a complex with the focal adhesion proteins in differentiated BC3H1 cells and alpha-sarcoglycan seems to modulate the function of the focal adhesion complex in these cells.

Hydrophilicity of quinolones is not an exclusive factor for decreased activity in efflux-mediated resistant mutants of Staphylococcus aureus

The elevated expression of the norA gene is responsible for efflux-mediated resistance to quinolones in Staphylococcus aureus (E.Y.W. Ng, M. Trucksis, and D.C. Hooper, Antimicrob. Agents Chemother. 38:1345-1355, 1994). For S. aureus transformed with a plasmid containing the cloned norA gene, SA113(pTUS20) (H. Yoshida, M. Bogaki, S. Nakamura, K. Ubukata, and M. Konno, J. Bacteriol. 172:6942-6949, 1990), and an overexpressed mutant, SA-1199B (G.W. Kaatz, S.M. Seo, and C.A. Ruble, J. Infect. Dis. 163:1080-1086, 1991), the MICs of norfloxacin increased 16 and 64 times compared with its MICs for the recipient and wild-type strains, SA113 and SA-1199, respectively. MICs of CS-940, however, increased only two and eight times, even though these two fluoroquinolones are similarly hydrophilic (apparent logPs of approximately -1). No good correlation was found, among 15 developed and developing quinolones, between the increment ratio in MICs and hydrophobicity (r = 0.61). Analysis of the quantitative structure-activity relationship among 40 fluoroquinolones revealed that the MIC increment ratio was significantly correlated with the bulkiness of the C-7 substituent and bulkiness and hydrophobicity of the C-8 substituent of fluoroquinolones (r = 0.87) and not with its molecular hydrophobicity (r = 0.47). Cellular accumulation of norfloxacin in SA-1199B was significantly lower than that in SA-1199, and it was increased by addition of carbonyl cyanide m-chlorophenyl hydrazone. On the other hand, accumulations of CS-940 in these strains were nearly identical, and they were not affected by addition of the protonophore.

The effects of N-methyl-D-aspartate (NMDA) and its competitive antagonist, 3-(2-carboxypiperazine-4-yl)propyl-1-phosphonic acid (CPP), injected into caudate-putamen on kindled amygdaloid seizures in rats

N-methyl-D-aspartate (NMDA) is an agonist of NMDA receptors and 3-(2-carboxypiperazine-4-yl)propyl-1-phosphonic acid (CPP) is an NMDA receptor antagonist. NMDA (1 or 2 nmol per side) or CPP (2.5 or 10 nmol per side) was injected into the bilateral caudate-putamen of amygdaloid-kindled rats. In addition, CPP (10 nmol) was ipsilaterally or contralaterally injected into the unilateral caudate-putamen. Either 20 min after NMDA or 60 min after CPP, the kindled amygdala was stimulated at the generalized seizure triggering threshold. In a few animals tested, injection of NMDA into the bilateral caudate-putamen produced transient spiking activity, with no clinical manifestations. This feature began about 5 min after the injection and lasted about 10 s. When these animals were excluded from the statistical analysis, NMDA in the caudate-putamen showed a weak and non-significant anticonvulsant action. Injection of CPP into the bilateral caudate-putamen caused no ictal change, but markedly suppressed the kindled seizures. Injection of CPP into the unilateral caudate-putamen, regardless of the site, did not cause any ictal change, or affect the stimulation of the amygdala. These findings suggest that: (1) NMDA receptors in the caudate-putamen facilitate the development of kindled amygdaloid seizures; (2) activation of NMDA receptors in the bilateral, but not in the unilateral, caudate-putamen is required for the generalization and expression of kindled amygdaloid seizures.