Increased nitric oxide biosynthesis in leukotoxin,9,10-epoxy-12-octadecenoate injured lung

We measured effluent nitric oxide levels using a chemiluminescence method from leukotoxin (Lx, a linoleate epoxide) injured isolated rat lungs perfused with physiological salt solution. Nitric oxide production from Lx-injured lung promptly increased and lasted for 20 min. Pretreatment with NG-monomethyl-L-arginine (LNMMA) significantly suppressed Lx-induced production of nitric oxide. Effluent from control lungs showed trace levels of nitric oxide. The wet to dry lung weight (WLW/DLW) after termination of the experiments was significantly elevated in Lx-treated lungs compared with that of LNMMA pretreated lungs or control lungs. There was a correlation between nitric oxide levels (at 10 min) and lung edema (WLW/DLW). Thus, nitric oxide plays a role in the pathogenesis of Lx-induced lung injury.

Oxygen stress induces an apoptotic cell death associated with fragmentation of mitochondrial genome

We have investigated the role of mitochondria on an active cell death, a feature of apoptosis, under the oxygen stress. An immortalized human fibroblast cell line (rho+) carrying normal mitochondrial genome (mtDNA) underwent an active cell death in 95% oxygen; 68% and 84% of the cells died on the 3rd and 4th days, respectively. By contrast, its derivative lacking mtDNA (rho 0) exhibited a marked resistance to cell death. PCR analyses using 180 primer pairs covering the entire regions of the mtDNA revealed extensive fragmentations of the mtDNA; 49 types of deletions increased up to 187 on the 3rd day. These results indicate that mtDNA and its fragmentation are the underlying molecular lesions in a cell death pathway induced by the oxygen stress.

Association of p120, a tyrosine kinase substrate, with E-cadherin/catenin complexes

p120 was originally identified as a substrate of pp60src and several receptor tyrosine kinases, but its function is not known. Recent studies revealed that this protein shows homology to a group of proteins, beta-catenin/Armadillo and plakoglobin (gamma-catenin), which are associated with the cell adhesion molecules cadherins. In this study, we examined whether p120 is associated with E-cadherin using the human carcinoma cell line HT29, as well as other cell lines, which express both of these proteins. When proteins that copurified with E-cadherin were analyzed, not only alpha-catenin, beta-catenin, and plakoglobin but also p120 were detected. Conversely, immunoprecipitates of p120 contained E-cadherin and all the catenins, although a large subpopulation of p120 was not associated with E-cadherin. Analysis of these immunoprecipitates suggests that 20% or less of the extractable E-cadherin is associated with p120. When p120 immunoprecipitation was performed with cell lysates depleted of E-cadherin, beta-catenin was no longer coprecipitated, and the amount of plakoglobin copurified was greatly reduced. This finding suggests that there are various forms of p120 complexes, including p120/E-cadherin/beta-catenin and p120/E-cadherin/plakoglobin complexes; this association profile contrasts with the mutually exclusive association of beta-catenin and plakoglobin with cadherins. When the COOH-terminal catenin binding site was truncated from E-cadherin, not only beta-catenin but also p120 did not coprecipitate with this mutated E-cadherin. Immunocytological studies showed that p120 colocalized with E-cadherin at cell-cell contact sites, even after non-ionic detergent extraction. Treatment of cells with hepatocyte growth factor/scatter factor altered the level of tyrosine phosphorylation of p120 as well as of beta-catenin and plakoglobin. These results suggest that p120 associates with E-cadherin at its COOH-terminal region, but the mechanism for this association differs from that for the association of beta-catenin and plakoglobin with E-cadherin, and thus, that p120, whose function could be modulated by growth factors, may play a unique role in regulation of the cadherin-catenin adhesion system.

Genotype and phenotype of severe mitochondrial cardiomyopathy: a recipient of heart transplantation and the genetic control

Comprehensive analyses of mitochondrial (mt)DNA of a recipient of heart transplantation at age 7 because of severe cardiomyopathy revealed three germ line point mutations, each one in the 12S rRNA gene, in the CO1 gene and in the cytochrome b gene, respectively. As the somatic mutation, extensive fragmentation of mtDNA associated with 212 kinds of deletions was detected in contrast to 5 kinds in an age-matched negative control. A recipient's positive control having almost the same base-substitutions and mutations with the recipient except one in the CO1 gene also developed severe cardiomyopathy died at age 20. The close relation between phenotype and mtDNA genotype provides the basis of our understanding of cell death and premature ageing.

Trace elements in ribs of elderly people and elemental variation in the presence of chronic diseases

Element concentrations in ribs obtained from elderly Japanese people (17 males and 28 females; mean age, 81.5 years) were determined by atomic absorption spectrometry (AAS), inductively coupled plasma atomic emission spectrometry (ICP-AES), and ICP mass spectrometry (ICP-MS). Nine elements--Na, Mg, P, K, Ca, Fe, Zn, Sr, and Pb--were determinable in most of the subjects by a combination of AAS and ICP-AES. The levels of these elements were generally comparable with those obtained in our previous study on ribs from younger Japanese. By the use of ICP-MS, Sn (median, 0.79 micrograms/g dry bone) and Ba (1.3 micrograms/g) were determinable in all of the subjects analysed (n = 35) and 18 other elements at lower concentration levels were also detected in some of the subjects. An exploratory statistical analysis was carried out to find element(s) of which level(s) in rib vary in the presence of degenerative chronic diseases, using information obtained from pathological autopsy reports and medical histories of the present subjects. It indicated that (i) Pb and Zn, (ii) Ba, and (iii) Sr levels in the ribs varied in the presence of cancer, cerebrovascular damage, and bone problems, respectively. The present results were discussed in relation to the results of the previous epidemiologic and experimental studies.

A new retinacular ligament and vein of the human temporomandibular joint

In the human temporomandibular joints of 14 Japanese cadavers, we observed a new retinacular ligament that connected to the retrodiskal pad posterolaterally and was accompanied by a vein draining the retrodiskal pad. This retinacular ligament originated from lateral to posterolateral part of the joint. The origin included the articular tubercle of the zygomatic process of the temporal bone. The ligament descended along the mandibular ramus to insert into the fascia of the masseter muscle at the mandibular angle. The vein originated from the venous plexus in the retrodiskal pad and ran parallel to the retinacular ligament, giving off branches to the retromandibular, transverse facial, and superfacial temporal veins. There were no remarkable differences in the size of the retinacular ligaments among individuals as well as between the left and right sides. The retinacular ligament had firm fibrous connections with the posterolateral part of the retrodiskal pad, where the external fibrous membrane of the articular capsule was lacking. These findings suggest that the retinacular ligament and its accompanying vein function together to maintain blood circulation during jaw movement and may also be related to the development of occlusal disorders.

Stimulation of interleukin-6 production of periodontal ligament cells by Porphyromonas endodontalis lipopolysaccharide

Interleukin-6 (IL-6), which is a multifunctional cytokine, has important roles in acute and chronic inflammation and may also be implicated in bone resorption. We examined the IL-6 production in periodontal ligament (PDL) cells which were treated with lipopolysaccharide (LPS) from several oral inflammatory pathogens. The LPS from Porphyromonas endodontalis, which was isolated from infected root canals and radicular cyst fluids, was more potent than the LPS from any other periodontal organisms examined. P. endodontalis LPS stimulated IL-6 release from PDL cells in a time- and dose-dependent manner. Northern blot hybridization analysis revealed that the IL-6 mRNA level in PDL cells was increased by P. endodontalis LPS. These results suggest that stimulation of the IL-6 release of PDL cells by P. endodontalis LPS may have a role in the progression of inflammation and alveolar bone resorption in periodontal and periapical diseases.

A variant of Gerstmann-Sträussler-Scheinker disease carrying codon 105 mutation with codon 129 polymorphism of the prion protein gene: a clinicopathological study

A case was reported of variant Gerstmann-Sträussler-Scheinker disease (GSS) carrying codon 105 mutation (Pro to Leu) with codon 129 polymorphism (Met/Val) of the prion protein (PrP) gene. The male patient had developed clumsiness of the right hand at age 42, and subsequently exhibited slowly progressive spastic paraparesis, ataxia, dysarthria, memory disturbance and apraxia. Myoclonus or periodic synchronous discharge was not observed. He died at age 53. The cerebral cortex and white matter showed atrophy, which was prominent in the frontal regions. There were numerous amyloid plaques throughout the cerebral cortex, which were reactive with the antibody to PrP, but not to beta/A 4 peptide. PrP immunostaining also revealed many amorphous deposits in the deep cortical layers, where neuronal loss and glial proliferation was evident. The cerebellum was almost intact, except a few amyloid plaques in the white matter. This variant GSS with codon 105 mutation has been found in four pedigrees, only in Japan up to the present, and the clinicopathological phenotype is summarized as follows: (1) onset at age 38-48, with a duration of 7-11 years, (2) prominent spastic paraparesis, associated with dementia and ataxia, (3) numerous amyloid plaques in the cerebral cortex, (4) amorphous PrP deposits with neuronal loss in the deep cortical layers, and (5) minor change of cerebellum.

[Antibacterial activities of a carbapenem antibiotic, biapenem (L-627), against penicillin-resistant Streptococcus pneumoniae]

Antibiotic susceptibilities were evaluated for 48 strains of Streptococcus pneumoniae collected in 1992-1993 at Ichihara City of Chiba Prefecture. Twenty two (46%) of the 48 strains were benzylpenicillin (PCG) insensitive or resistant (PRSP) judged from the MICs of PCG to higher than 0.1 microgram/ml. MICs of piperacillin and cefotaxime increased as the MICs of PCG increased. However, elevations of MICs of imipenem and biapenem (L-627) were small in spite of the increases of MICs of PCG. L-627 was effective in a case of purulent meningitis due to PC-insensitive S. pneumoniae. Thus, L-627 is a candidate to be used in treatment of PRSP infections including purulent meningitis.

A novel type of life cycle "delayed homothallism" in Saccharomyces cerevisiae wy2 showed slow interconversion of mating-type

Saccharomyces cerevisiae wy2 segregated to 2 mater and 2 non-mater in relation to mating ability. The non-mater segregants behaved as the normal type of homothallic life cycle. On the other hand, the mater segregants gradually formed spores during successive subcultures, indicating that slow interconversion of mating-type happened to occur during subcultures. We termed this novel type of life cycle "delayed homothallism". The results of complementation tests with standard ho strains and introduction of a wild type HO gene showed that delayed homothallism was caused by a defective HO gene. The amino acid sequence deduced from the nucleotide sequence of the wy2 HO gene differed from the wild type HO gene in three amino acid residues. In the carboxy terminus of HO protein, there are three repeats of cysteine and histidine that are postulated to play a role in binding of HO protein to DNA. However, wy2 HO protein lacked one such repeat at residues Cys470-His475, where His was replaced by Leu.

Effect of nisoldipine on red cell deformability and platelet aggregation in stroke patients

Reduced red cell deformability and increased platelet aggregability are assumed to contribute to various ischemic diseases, and it has been postulated that these abnormalities may be improved by drug treatment. In this study, the effect of nisoldipine (Bay K 5552, CAS 63675-72-9) on red cell deformability and platelet aggregation in patients with chronic ischemic cerebrovascular disease and hypertension was examined. Administration of nisoldipine for 4 weeks caused a significant improvement of red cell deformability and platelet aggregability without causing any adverse effects.

Leukotoxin, a linoleate epoxide: its implication in the late death of patients with extensive burns

Burn death based on circulatory shock is often encountered after recovery from primary shock in patients with deep and extensive burns, i.e., late death. Several toxic substances have been proposed, however, the responsible substance remains obscure. Since we have found leukotoxin, a highly cytotoxic linoleate epoxide biosynthesized by neutrophils, in the burned skin, in the present study we determined plasma leukotoxin concentrations in various degree of 30 burn patients. C-reactive protein and circulatory white blood cells were also measured. A significantly high mortality rate of patients with extensive burns (burn surface area over 70%) was observed compared with that in patients with burn surface area under 70%, and significantly high leukotoxin concentrations were observed within a week, and 3 weeks after the thermal injury in patients with extensive burns compared with those in patients with burn surface area under 70%. There were two peaks of plasma leukotoxin concentrations, i.e., the early phase (within 1 week) and the late phase (over 1 week) in patients with extensive burns. Plasma leukotoxin concentrations significantly correlated with burn surface area in the early phase, and similar correlations were observed in the late phase. A significantly high mortality rate (61%) of patients with peak leukotoxin concentrations over 30 nmol/ml was observed compared with 8% for those below 30 nmol/ml. Plasma leukotoxin concentration correlated significantly to C-reactive protein concentration, log (leukotoxin nmol/ml) = 0.042 x C-reactive protein (mg/dl) + 0.74, (r = 0.83, P < 0.01) in the late phase. From these results, it is concluded that leukotoxin is produced in patients with burns particularly in the late phase of extensive burns, and leukotoxin might play an important role in the tissue destructive procedure associated with severe burns.

Combination chemotherapy with Tegafur. Uracil (UFT), etoposide, adriamycin and cisplatinum (UFT-EAP) for advanced gastric cancer

Thirty-four patients with advanced gastric cancer were treated with combination chemotherapy employing Tegafur-Uracil (UFT), etoposide, Adriamycin, and Cisplatinum (CDDP) (UFT-EAP therapy). An objective partial response was obtained in 16 patients (47%) and the median duration of remission was 12.2 months. The 50% survival time for all 34 patients was 10 months. Patients with moderately or well differentiated adenocarcinoma responded well (13/19, 68%), while those with undifferentiated adenocarcinoma showed a poor response (3/15, 20%). Six responding patients were noted to have no evidence of viable cancer at the primary site by endoscopic biopsy, and underwent gastrectomies. The resected specimens showed complete disappearances of the primary tumors in four patients. The median survival time for the patients receiving gastrectomies was 24 months. The regimen was very well tolerated, apart from moderate bone marrow suppression. Our results suggest that patients with advanced gastric cancer can be effectively treated with UFT-EAP chemotherapy.

Partial splenic embolization for Felty's syndrome: a 10-year followup

Partial splenic embolization was performed in a case of Felty's syndrome in 1980. The granulocyte count has since remained normal without serious infections for the 10 years after the procedure. This is the first report of partial splenic embolization in this syndrome. This treatment may have an advantage over splenectomy because the defense mechanisms of the spleen are preserved and overwhelming infections may occur less frequently.

Fragmentation of human heart mitochondrial DNA associated with premature aging

Point mutations, oxygen damage and deletions in the heart mitochondrial (mt) DNA of a 19-year-old male patient with premature aging, who died of mitochondrial cardiomyopathy, were comprehensively analyzed. With total base-sequencing, one syn- mutation in the tRNA(Asp) gene and one mit-mutation in the ND3 gene were demonstrated. Using microHPLC/MS, 0.20% of the total deoxyguanosine (dG) were proved to be converted into its hydroxy-radical adduct, 8-hydroxy-dG, of which amount corresponds to that in normal subjects of 78 years old. The total detection system for mtDNA deletions, using 180 kinds of primer pairs, revealed extensive fragmentation of mtDNA; 235 types of deletions existed with various sizes, 97 of which yielded mtDNA minicircles lacking both of the replication origins of light- and heavy-strands. Deleted mtDNA accounted for 84% of the total mtDNA. In a man died from an accident at age 28 having almost the same mtDNA genotype except syn-, 50 types of deleted mtDNA, accounting for 15% of the total, were detected in his heart mtDNA. These results will present a clue to an unidentified mechanism of somatic mtDNA replication and the molecular basis of aging heart.

[Clinical experience with modified Studer's bladder substitute]

We modified Studer's bladder substitute technique and constructed continent urinary reservoir for 7 patients with bladder tumors after transprostatic cystoprostatectomy. Studer's bladder substitute technique is characterized by both a tubular isoperistatic proximal limb of 20 cm of the ileum in continuity with the pouch constructed using the detubularized ileum and the ureters reimplanted into the proximal part of the limb using a simple lateral anastomosis of the ureters to the end of the limb. Our modifications, transprostatic resection, was that distal one third or fourth of the prostate was left after cystoprostatectomy followed by either enucleation of the whole residual prostatic tissue including the urethra (type II) or sharp resection of the tissue leaving the urethra (type III). A small hole in the lowest part of the pouch was anastomosed either to the residual prostatic capsule (type II) or to the residual prostatic urethra (type III). Our modified Studer's technique was simple, easy to perform, and had low risk of massive bleeding especially from the central vein overlying the appex of the prostate. Clinical results were as follows; 1) all patients were satisfied with the passing of their urine per urethra without any cutaneous stoma, 2) no patients had clinical signs of pyelonephritis after discharge, 3) urine was not infected.(ABSTRACT TRUNCATED AT 250 WORDS)

A rare portosystemic shunt detected by MRI and diagnosed by dynamic liver scintigraphy with Tc-99m phytate

Although various types of portosystemic shunts with portal hypertension have been widely reported, a collateral circulation near the pancreas head is rare. The authors report a case of a rare portosystemic shunt surrounding the pancreatic head, which was diagnosed by dynamic liver scintigraphy using Ikoma's scintigraphic criteria for the presence of portosystemic shunts. According to these criteria, abnormal accumulation of radioactivity at various abdominal sites (not identified on static images after the dynamic study) on 6 or more continuous frames of 5-second intervals (i.e., for 30 seconds or more after the arterial phase) indicates the presence of a portosystemic shunt. If liver scintigraphy is performed on a patient with portal hypertension, the dynamic study is valuable in the detection and diagnosis of a portosystemic shunt.

[Leber's hereditary optic neuropathy with onset at the age of 54 years]

We report a 55-year-old Japanese man who had an onset of bilateral progressive blurring of vision at age 54 years. His younger sister had diminished visual acuity since 14 years of age. On neurologic examination, bilateral optic atrophy was present. He could only count the digit numbers at 40 cm-distance with his right eye, and the visual acuity of the left eye was 0.08. Otherwise, neurologic examination was unremarkable. The PCR analysis of mitochondrial DNA prepared from whole blood revealed a G to A mutation at the nucleotide 11,778; the so-called Wallace's mutation. He was diagnosed as Leber's hereditary optic neuropathy. It is rare to see a patient with LHON with the onset after 50 years of age.