Administration of melatonin and related indoles prevents exercise-induced cellular oxidative changes in rats

In an attempt to define the role of the pineal hormone melatonin and two analogues (5-methoxytryptamine, 5MT, and 6-hydroxymelatonin, 6HM) in limiting oxidative stress, the present study investigated the changes in glutathione, lipid peroxidation, and the activity of the antioxidant enzyme glutathione peroxidase after exercise (swimming for 60 min) with or without treatment with the indolamines mentioned. Lipid peroxidation was measured by estimating tissue levels of malondialdehyde and 4-hydroxyalkenals; the experimental animals in these studies were male Sprague-Dawley rats. In the liver, swimming exercise increased the levels of reduced glutathione (GSH) and also significantly increasing oxidized glutathione (GSSG), while decreasing the GSH/GSSG ratio, an index directly related to oxidative stress. When the animals were treated with melatonin, the concentrations of GSH and GSSG were also increased after swimming; however, no reduction in the GSH/GSSG ratio appeared. In the animals treated with 6HM the changes were the same as in those treated with melatonin. In muscle as well, the concentration of GSH and the GSH/GSSG ratio were decreased following 60 min of swimming. Pretreatment of the rats with melatonin prevented these effects. Pretreatment of the rats with both 5MT and 6HM also prevented the changes. Brain GSH/GSSG ratio was not affected by either exercise or indolamine administration. Swimming enhanced lipid peroxidation in the liver, muscle and brain; however, this was prevented in animals treated with melatonin or 6HM before swimming. Glutathione peroxidase was significantly elevated after exercise in the brain but not in the liver and muscle. It is concluded that swimming imposes a severe oxidative stress and suggests that melatonin and, to a lesser degree, 5MT and 6HM confer protection against the oxidative damage associated with swimming for 60 min. This mechanism may be reasonably attributed to their indole structure, which possibly allows these molecules to act as free-radical scavengers.

Lethal effect of recombinant human Fas ligand in mice pretreated with Propionibacterium acnes

Fas ligand (FasL) is a type II membrane protein. Binding of FasL to its receptor, Fas, induces apoptosis. Matrix metalloproteinase cleaves the membrane-bound human FasL to yield the active soluble form. Here, we have produced a large amount of human soluble rFasL using the yeast, Pichia pastoris. The purified rFasL was found to be glycosylated and to exist as a trimer. The rFasL was effective in inducing apoptosis in a Fas-expressing T cell or a fibroblast cell line. The ID50 of rFasL for mouse Fas-expressing T cells was about 0.5 ng/ml. The killing process with rFasL was quick. That is, >80% Fas-expressing mouse cells were killed within 1 h by a saturation concentration of human rFasL. Intravenous administration of 500 microg of human rFasL had a lethal effect in mice. When the mice were pretreated with Propionibacterium acnes, the subsequent injection of 30 microg of human rFasL induced hepatic failure and killed the mice within 24 h. These results indicated that the soluble human FasL is active in inducing apoptosis in vitro and in vivo, and its deleterious effect may be strengthened in patients who are suffering from bacterial infection.

Formation of actin stress fibers and focal adhesions enhanced by Rho-kinase

The small guanosine triphosphatase (GTPase) Rho is implicated in the formation of stress fibers and focal adhesions in fibroblasts stimulated by extracellular signals such as lysophosphatidic acid (LPA). Rho-kinase is activated by Rho and may mediate some biological effects of Rho. Microinjection of the catalytic domain of Rho-kinase into serum-starved Swiss 3T3 cells induced the formation of stress fibers and focal adhesions, whereas microinjection of the inactive catalytic domain, the Rho-binding domain, or the pleckstrin-homology domain inhibited the LPA-induced formation of stress fibers and focal adhesions. Thus, Rho-kinase appears to mediate signals from Rho and to induce the formation of stress fibers and focal adhesions.

Antibodies to glutamic acid decarboxylase in Japanese diabetic patients with secondary failure of oral hypoglycaemic therapy

Some patients with non-insulin-dependent (Type 2) diabetes mellitus (NIDDM) are positive for antibodies to glutamic acid decarboxylase (anti-GAD), which have been shown to be a useful marker for the diagnosis and prediction of insulin-dependent (Type 1) diabetes mellitus (IDDM). Anti-GAD positive NIDDM patients tend to develop insulin deficiency. We investigated the prevalence of anti-GAD in 200 NIDDM with secondary failure of oral hypoglycaemic therapy (SF) and 200 NIDDM well controlled by diet and/or sulphonylurea agents (NSF). Twenty-two of 200 (11%, p < 0.05) SF patients and 6 of 200 (3%) NSF patients were anti-GAD positive. The positive. The positive rate for anti-GAD was as high as 23.8% in the non-obese and insulin deficient SF patients. The SF patients with anti-GAD tended to be non-obese and to have an impaired release of endogenous insulin. The internal before development of secondary failure was not associated with the presence of anti-GAD in this study. In conclusion we found that anti-GAD was positive in as many as 11% of the SF patients, suggesting that autoimmune mechanisms may play an important role in the pathogenesis of secondary failure or sulphonylurea therapy.

[Social support of chronically-ill children and healthy children]

The purpose of this study was to describe characteristics of social support of chronically-ill children and to compare social support of chronically-ill children with those of healthy children. Subjects consisted of 204 chronically-ill children aged between 9 and 18 years old and 544 healthy children aged between 10 and 17 years old. Results of this study were as follows: 1. In both chronically-ill children and healthy children, parents' support score and teachers' support score were significantly higher in elementary school children than high school students. In both groups, friends' support score was significantly higher in girls than boys. 2. Chronically-ill children reported significantly higher scores of parents' support, friends' support and teachers' support than those of healthy children. 3. Parents' support score was significantly lower in children with diabetes than those with asthma and cancer. 4. The total score of social support and teachers' support score were significantly lower in children with employed mothers than those with unemployed mothers. 5. The total social support score of children who participated in non-sports extracurricular activities was significantly higher than those of children who did not participate in non-sports activities.

Pathological consideration of a "blister-like" aneurysm at the superior wall of the internal carotid artery: case report

OBJECTIVE AND IMPORTANCE

Although the incidence is low, a very small aneurysm with a thin wall and no neck arises at the superior wall of the supraclinoid portion of the internal carotid artery and is called a "blister-like" aneurysm. However, the pathogenesis of such a vascular lesion remains uncertain.

CLINICAL PRESENTATION

A 57-year-old man developed a fatal subarachnoid hemorrhage caused by the rupture of a blister-like aneurysm at the superior wall of the internal carotid artery. An autopsy was performed, and the lesion was pathologically examined.

RESULTS

The internal elastic lamina and media had disappeared at the border between the eccentrically sclerotic and normal carotid wall. The gap in the internal elastica was covered with normal adventitia and fibrinous tissue. This portion was not composed of collagenous tissue as ordinarily seen in an aneurysmal wall. Neither infiltration of inflammatory cells nor dissection of the artery were observed.

CONCLUSION

The blister-like aneurysm appeared to be a laceration of the carotid wall based on degeneration of the internal elastic lamina.

Acidification of vacuoles is required for autophagic degradation in the yeast, Saccharomyces cerevisiae

Acidification inside vacuoles has been shown to play a key role in a number of physiologically important cellular events. We studied the role of vacuolar membrane H(+)-ATPase in the autophagic process of Saccharomyces cerevisiae. Mutants lacking VMA genes which encode their subunits of the vacuolar H(+)-ATPase accumulated autophagic bodies in vacuoles on starvation. vma mutants also had a defect in protein degradation induced by starvation. In vma mutants, the activities of vacuolar proteases were remarkably lower than those of the wild-type. Overexpression of vacuolar proteases did not overcome the defect in the disintegration of autophagic bodies in vma mutant, even the overexpressed proteinase A and proteinase B being substantially localized to the vacuolar compartment and undergoing proper proteolytic maturation. Our results showed that the acidification of vacuoles is not required for the formation and delivery of autophagosomes to vacuoles, but is essential for the disintegration of autophagic bodies.

Remodeling of allogeneic and autogenous patellar tendon grafts in rats

The differences in remodeling among frozen allografts, frozen autografts, and fresh autografts were investigated using a patellar tendon transplantation model in 2 different strains of rats. In this study, isografting (transplantation among the same strain inbred animals) was adopted as an autograft model. This method makes it possible to set up a frozen autograft model. Evaluation included mechanical properties determined during tensile failure tests, cross sectional area, histologic findings, and collagen fibril distribution. Recipient rats were euthanized at 4, 8, 12, and 24 weeks after transplantation (n = 5, in each group and in each period). The frozen allografts showed significantly less tensile strength than did the frozen autografts at 4 weeks, but this difference was transient and diminished by 8 weeks. The tensile strength of the fresh autografts was significantly greater than that of the frozen autografts at 8 weeks or the frozen allografts at 8 and 12 weeks. It was suggested that freeze thawing has adverse effects on the remodeling of fresh autografts in this extraarticular graft model. The cross sectional area for each type of graft at each posttransplantation period was about twice as large as that before transplantation. The collagen fibril profile of the frozen allografts was similar to that of the frozen autografts. However, the fresh autografts showed a greater number of large diameter fibrils and a lesser number of small diameter fibrils than did the other 2 frozen groups.

Rapid loss in the mitochondrial membrane potential during geranylgeranoic acid-induced apoptosis

A synthetic geranylgeranoic acid (GGA) induced apoptotic cell death in a human hepatoma cell line, HuH-7, but not in mouse primary cultured hepatocytes. Prior to chromatin condensation, GGA induced a dramatic loss of the mitochondrial membrane potential in 1 hour and in a dose dependent manner in HuH-7 cells, but not in the primary hepatocytes. Pretreatment with synthetic tetrapeptide cysteine protease inhibitor, either acetyl-Tyr-Val-Ala-Asp-chloromethylketone or acetyl-Asp-Glu-Val-Asp-aldehyde, blocked GGA-induced apoptosis without preventing a rapid loss of the mitochondrial membrane potential. alpha-Tocopherol prevented the cells from GGA-induced apoptosis as well as from a rapid loss of the membrane potential. The present study strongly suggests that GGA induces apoptosis in hepatoma cells through derangement of mitochondrial function and subsequent activation of the cysteine protease cascade.

Electrochemical disinfection of drinking water using an activated-carbon-fiber reactor capable of monitoring its microbial fouling

An electrochemical reactor employing activated carbon fibers (ACF) was constructed for the disinfection of bacteria in drinking water. The application of an alternating potential of 1.0 V and -0.8 V versus a saturated calomel electrode, for disinfecting and desorbing bacteria, enabled reactor operation for 840 h. Drinking water was passed through the reactor in stop/flow mode: 300 ml/min flow for 12 h and no flow for 12 h, alternately. The bacterial cell density in treated water was always been less than 20 cells/ml. It was also found that the formation of biofilm on the ACF reactor caused an increase in current, enabling the self-detection of microbial fouling.

Role of apoptosis in duct obstruction-induced pancreatic involution in rats

It has been recognized in mammals that after pancreatic duct obstruction, acinar cells progressively disappear and pancreatic islets are preserved. Previous studies by electron microscopy have suggested the involvement of apoptosis in acinar cell deletion. In the present study, we employed molecular biological methods and investigated whether acinar cell deletion is due to apoptosis. In male Sprague-Dawley rats, pancreatic duct ligation was performed through a left paramedian incision. Pancreatic tissue was studied at each of the following intervals after ligation: 3, 6, 12, 18, and 24 h and 2, 3, 5, and 7 days. DNA fragmentation was determined by in situ labeling of DNA strand breaks on tissue sections [fluorescein-labeled terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling method (TUNEL)] and by electrophoretic detection of the fragments of extracted DNA. Tissue sections were also examined by hematoxylin/eosin staining and immunohistochemical staining of insulin. Pancreatic duct ligation induced acinar cell deletion by day 5. Pancreatic tissue from control rats demonstrated no TUNEL-positive nuclei. In contrast, acinar cells from rats 12 h to 5 days after duct ligation showed TUNEL-positive nuclei. The number of TUNEL-positive nuclei was maximum 2 days after duct ligation. Electrophoresis showed DNA fragmentation after duct ligation. Control rats showed a genomic DNA pattern. Islets were preserved throughout the experimental period in duct-ligated rats and control rats. The results suggest that apoptosis may be the dominant form of acinar cell death in the rat pancreatic duct ligation model.

The structure of the promoter region for rat inducible nitric oxide synthase gene

The nucleotide sequences of the promoter region for rat inducible nitric oxide synthase (iNOS) were elucidated. The sequences were highly homologous with the mouse iNOS gene. The regulation of the iNOS gene may be distinguished between rodent and mammalian.

Estimation of minimal size of translocated chromosome segments detectable by fluorescence in situ hybridization

Apparent non-reciprocal translocations are commonly observed using fluorescence in situ hybridization. We hypothesize that these are 'hidden' reciprocals due to one translocated segment being too small to detect. Assuming that the translocation breakpoints distribute randomly, the proportion of reciprocal to non-reciprocal exchanges can be used to estimate the minimal detectable size of translocated segments. To estimate segment size in this study, cytogenetic data for 120 A-bomb survivors were used. Among 2295 aberrant metaphases, 1629 exhibited reciprocal translocations and 666 non-reciprocal. Of the non-reciprocal translocations, 501 showed only a painted chromosome segment, translocated to an unpainted chromosome with centromere, and 165 showed only an unpainted chromosome segment, translocated to a painted chromosome with centromere. On the basis of the above two assumptions, we obtained the most likely estimates for minimal detectable sizes: 11.1 +/- 0.8 Mb for the painted and 14.6 +/- 0.6 Mb for the unpainted chromosomes. The implications of these findings are discussed.

Morphological analysis of germ cell apoptosis during postnatal testis development in normal and Hsp 70-2 knockout mice

The present study examined the occurrence of apoptotic cell death in the testis of wild-type mice from postnatal days 3 to 26 and in juvenile Hsp 70-2 knockout mice. Adult Hsp 70-2 knockout males are infertile and lack spermatids and spermatozoa (Dix et al. [1996a] Proc. Natl. Acad. Sci. U.S.A. 93:3264-3268). To identify the cell types undergoing apoptosis, we also examined the relationship between the occurrence of apoptotic cell death and the expression pattern of the Hsp 70-2 gene product (heat-shock protein 70-2 [HSP70-2]; marker for spermatocytes and spermatids), germ cell nuclear antigen 1 (GCNA1;marker for spermatogonia and spermatocytes), and vimentin (marker for Sertoli cells). This study shows that during postnatal development of the wildtype mouse testis (1) the percentage of apoptotic cell death detected by the TdT-mediated dUTP-biotin nick end labeling (TUNEL) method is higher in mice from days 8 to 22 than in younger or older mice, (2) the majority of apoptotic cells are spermatogonia and less frequently are spermatocytes, and (3) the degenerative cell death of spermatogonia and primary spermatocytes involves apoptosis with fragmentation of DNA. The analysis of apoptotic cell death in the testes of juvenile Hsp 70-2 knockout mice showed an additional increased level of apoptosis at day 17, during the first wave of spermatogenesis, in pachytene spermatocytes.

A case of Bednar tumor. Immunohistochemical positivity for CD34

A 42-year-old Japanese man with a Bednar tumor is described. The skin showed a slightly elevated, red, partially dark blue, dermal nodule growing into the deep subcutaneous tissue. The histological specimen showed two types of tumor cells, spindle-formed cells with no melanin granules and melanin-laden cells. Immunohistochemical stainings for CD34 and S-100 protein revealed that the former cells showed positivity only for CD34, while the latter were only positive for S-100 protein. These results suggest that the Bednar tumor is a dermatofibrosarcoma protuberans in which melanin-laden cells coexist.

Physical and functional interactions between Stat5 and the tyrosine-phosphorylated receptors for erythropoietin and interleukin-3

Erythropoietin (Epo) and interleukin-3 (IL-3) stimulate activation of the Jak2 tyrosine kinase and induce tyrosine phosphorylation and activation of Stat5. In the present study, we have shown that Epo or IL-3 stimulation induces binding of Stat5 to the tyrosine-phosphorylated Epo receptor (EpoR) or IL-3 receptor beta subunit (betaIL3), respectively, in IL-3-dependent 32D cells expressing the EpoR. The binding of Stat5 to these cytokine receptors was shown to be rapid and transient, occurring within 1 minute of stimulation of cells and significantly decreasing after 5 minutes of cell treatment. In vivo binding experiments in COS cells showed that binding of Stat5 to the EpoR was mediated through the Stat5 Src homology 2 (SH2) domain. In vitro binding studies further showed that Stat5, but not other Stats examined, bound specifically to tyrosine-phosphorylated recombinant EpoR fusion proteins. In these in vivo and in vitro binding studies, Stat5 bound, albeit to a lesser degree, to truncated EpoR mutants in which all the intracellular tyrosines except Y-343 were removed. Furthermore, EpoR-derived synthetic phosphotyrosine peptides corresponding to Y-343, Y-401, Y-431, and Y-479 inhibited the in vitro binding of Stat5. When expressed in 32D cells, a mutant EpoR in which all the intracellular tyrosines were removed by carboxy-terminal truncation showed a significantly impaired ability to induce tyrosine phosphorylation of Stat5, particularly at low concentrations of Epo, but exhibited an increased sensitivity to Epo for growth signaling as compared with the wild-type EpoR. These results indicate that Stat5 specifically and transiently binds to the EpoR through the interaction between the Stat5 SH2 domain and specific phosphorylated tyrosines, including Y-343, in the EpoR cytoplasmic domain. It was implied that betaIL3 may also have similar Stat5 docking sites. The Stat5 docking sites in the EpoR were shown to facilitate specific activation of Stat5, which, however, may not be required for the EpoR-mediated growth signaling.

Guillain-Barré syndrome and ethylene diamine tetraacetic acid-dependent pseudothrombocytopenia associated with mumps

A 35-year-old man with Guillain-Barré syndrome and ethylene diamine tetraacetic acid (EDTA)-dependent pseudothrombocytopenia associated with serologically-confirmed mumps is presented. A polyneuropathy developed 18 days after the onset of mumps, that improved with plasmapheresis. A decreased platelet count was observed 25 days after the onset of mumps attributed to platelet agglutination in blood anticoagulated with EDTA, and the agglutination was prevented by other anticoagulants. Guillain-Barré syndrome associated with mumps is rare and EDTA-dependent pseudothrombocytopenia following mumps has never been documented. This represents the first report of Guillain-Barré syndrome and EDTA-dependent pseudothrombocytopenia following mumps. Furthermore, our findings suggest activation of the humoral immune response as a potential pathogenesis.

Synthesis and biological activity of four kinds of reversed peptides

We have synthesized four kinds of reversed peptides of various physiologically active peptides, which inhibit TNF (tumor necrosis factor) cytotoxicity, produce NGF (nerve growth factor), exert antimicrobial activity and inhibit cell attachment, respectively. They were examined for their biological activity in comparison with that of normal peptides, that is, naturally occurring peptides. The reversed peptides induce similar activities, but to a lesser extent than those of the normal peptides, respectively. These results indicate that there may be conformationally ambiguous binding in some of the naturally occurring ligand-protein interactions. This method may be useful as a tool to rapidly generate a novel lead peptide with the desired biological function from a naturally occurring active peptide.

Clinicopathological study of choroid plexus tumors: immunohistochemical features and evaluation of proliferative potential by PCNA and Ki-67 immunostaining

This report concerns the retrospective immunohistochemical characterization and evaluation of the proliferative potential of eight choroid plexus tumors (CPTs) that included six cases of choroid plexus papilloma (CPP), one of whom had a recurrence, and two cases of choroid plexus carcinoma (CPC). Antibodies to prealbumin, glial fibrillary acidic protein (GFAP), vimentin, keratin, and carcinoembryonic antigen (CEA) were used to determine the immunohistochemical features of interest. The proliferative potential was evaluated with antibodies to proliferating cell nuclear antigen (PCNA) and Ki-67. Antibody binding was visualized by the avidin-biotin-peroxidase complex (ABC) method. Immunoreactivity was scored on a-to 4+ scale, and in the case of PCNA and Ki-67, expected as staining index (SI). All seven CPP specimens were immunostained for prealbumin, but not for CEA. Expression of GFAP, vimentin and keratin varied from one CPP case to another. Both CPCs expressed CEA, but not prealbumin, GFAP and keratin; one of them was vimentin-positive. As determined by immunostaining for Ki-67, the proliferative potential was lower in the CPPs than in the CPCs. Among the former, the highest Ki-67 SI was seen in the primary lesion of a recurring papilloma. On the other hand, immunostaining for PCNA gave less consistent SI values. Our results show that immunohistochemical assays for prealbumin and CEA expression are of significant value for the differential diagnosis of CPPs and CPCs, and that high Ki-67 SI values may serve as an indicator of CPP recurrence, even if the primary lesion is benign.

Cloning and sequence analysis of a cDNA encoding salmon (Onchorhynchus keta) liver transglutaminase

We isolated cDNA clones encoding a transglutaminase (TGase: EC 2.3.2.13) from a salmon (Onchorhynchus keta) cDNA library prepared from the liver. In the cDNA sequence combined, an open reading frame coding for a protein of 680 aa was found. The deduced sequence showed a considerable similarity (62.4%) to that of red sea bream TGase. By comparison of sequence similarity to other TGases, the structure of salmon TGase was like tissue type TGases, rather than membrane-associated type or plasma type TGases. As a structural feature of salmon TGase, 3 aa residues were substituted in the 25 aa sequence around the active site Cys residue, which is conserved among several tissue type TGases. The critical residues thought to form the catalytic-center triad (Cys272, His331, and Asp301) were found in the highly conserved region, but the region surrounding Tyr511, which corresponds to the residue participates in hydrogen-bond interactions of active center domain, was less similar to other TGases, except for red sea bream TGase. These finding suggests that the overall structure of fish TGase resembles tissue-type TGases, but has some unique structure.