Effects of behavioural activation on the neural basis of other perspective self-referential processing in subthreshold depression: a functional magnetic resonance imaging study.

BACKGROUND: It has been demonstrated that negatively distorted self-referential processing, in which individuals evaluate one's own self, is a pathogenic mechanism in subthreshold depression that has a considerable impact on the quality of life and carries an elevated risk of developing major depression. Behavioural activation (BA) is an effective intervention for depression, including subthreshold depression. However, brain mechanisms underlying BA are not fully understood. We sought to examine the effect of BA on neural activation during other perspective self-referential processing in subthreshold depression. METHOD: A total of 56 subjects underwent functional magnetic resonance imaging scans during a self-referential task with two viewpoints (self/other) and two emotional valences (positive/negative) on two occasions. Between scans, while the intervention group (n = 27) received BA therapy, the control group (n = 29) did not. RESULTS: The intervention group showed improvement in depressive symptoms, increased activation in the dorsal medial prefrontal cortex (dmPFC), and increased reaction times during other perspective self-referential processing for positive words after the intervention. Also, there was a positive correlation between increased activation in the dmPFC and improvement of depressive symptoms. Additionally, there was a positive correlation between improvement of depressive symptoms and increased reaction times. CONCLUSIONS: BA increased dmPFC activation during other perspective self-referential processing with improvement of depressive symptoms and increased reaction times which were associated with improvement of self-monitoring function. Our results suggest that BA improved depressive symptoms and objective monitoring function for subthreshold depression.

Interactions between two propagating waves in rat visual cortex.

Sensory-evoked propagating waves are frequently observed in sensory cortex. However, it is largely unknown how an evoked propagating wave affects the activity evoked by subsequent sensory inputs, or how two propagating waves interact when evoked by simultaneous sensory inputs. Using voltage-sensitive dye imaging, we investigated the interactions between two evoked waves in rat visual cortex, and the spatiotemporal patterns of depolarization in the neuronal population due to wave-to-wave interactions. We have found that visually-evoked propagating waves have a refractory period of about 300 ms, within which the response to a subsequent visual stimulus is suppressed. Simultaneous presentation of two visual stimuli at different locations can evoke two waves propagating toward each other, and these two waves fuse. Fusion significantly shortens the latency and half-width of the response, leading to changes in the spatial profile of evoked population activity. The visually-evoked propagating wave may also be suppressed by a preceding spontaneous wave. The refractory period following a propagating wave and the fusion between two waves may contribute to visual sensory processing by modifying the spatiotemporal profile of population neuronal activity evoked by sensory events.

Measurement of urinary zearalenone concentrations for monitoring natural feed contamination in cattle herds: On-farm trials.

The aims of the present study were to investigate the efficacy of measuring bovine urinary zearalenone (ZEN) concentrations by using a commercially available ELISA method in cattle kept under different feeding conditions to monitor the natural contamination of feeds at the farm level, and to investigate the effects of supplementation of a mycotoxin adsorbent (MA) product in the feed based on urinary ZEN concentration. First, Japanese Black cattle herds kept for breeding (4 herds) and fattening (4 herds) purposes were provided with similar feeding conditions. Then, urinary samples from 5 cows in each herd were collected and analyzed. Second, dairy cows from 1 herd fed with total mixed rations (TMR) were selected. After thorough mixing of the MA (40 g/d) with TMR, the supplemented TMR was fed according to the following schedule: with MA for 2 wk, without MA for 3 wk; then with MA for 2 wk and without MA for 6 wk. Urine samples were collected from cows (n = 6 to 7) and examined before and after each interval. Zearalenone concentrations were measured by the ELISA and liquid chromatography-tandem mass spectrometry methods. The concentration of ZEN and its metabolites was expressed after creatinine (Crea) correction [ZEN or metabolites (pg/mL)/Crea (mg/dL); pg/mg of Crea]. In the first experiment, the urinary concentrations of ZEN and its metabolites were variable in all herds, and significant differences were observed between herds. In 1 fattening herd, in particular, urinary ZEN concentrations were greater (P < 0.001) than in the other 3 herds. This might reflect significant natural ZEN contamination of the feed at the farm level. In Exp. 2, urinary ZEN concentrations displayed peculiar trends after supplementation with MA. After 2 wk of supplementation, a significant decrease of ZEN (P < 0.05) was observed. Zearalenone concentrations remained at a reduced amount during 3 wk without MA supplementation and 2 wk with MA supplementation. When MA was not added to the feed for the next 6 wk, the concentrations increased to the original quantity. These findings indicate the usefulness of measuring concentrations of urinary ZEN and its metabolites not only for monitoring the natural ZEN contamination of cattle feed at the farm level but also for in vivo evaluation of MA function after supplementing feeds with MA.

Protein phosphatase Dusp26 associates with KIF3 motor and promotes N-cadherin-mediated cell-cell adhesion.

Recent studies have demonstrated essential functions for KIF3, a microtubule-directed protein motor, in subcellular transport of several cancer-related proteins, including the beta-catenin-cadherin(s) complex. In this study, we report identification of the protein-phosphatase Dusp26 as a novel regulator of the KIF3 motor. Here we undertake yeast two-hybrid screening and identify Kif3a, a motor subunit of the KIF3 heterotrimeric complex, as a novel Dusp26-binding protein. Co-immunoprecipitation and colocalization experiments revealed that Dusp26 associates not only with Kif3a, but also with Kap3, another subunit of the KIF3 complex. Dephosphorylation experiments in vitro and analysis using mutant forms of Dusp26 in intact cells strongly suggested that Dusp26 is recruited to the KIF3 motor mainly by interaction with Kif3a, and thereby dephosphorylates Kap3. Forced expression of Dusp26, but not its catalytically inactive mutant, promoted distribution of beta-catenin/N-cadherin, an established KIF3 cargo, to cell-cell junction sites, resulting in increased cell-cell adhesiveness. We also showed that Dusp26 mRNA expression was downregulated in human glioblastoma samples. These results suggest previously unidentified functions of Dusp26 in intracellular transport and cell-cell adhesion. Downregulation of Dusp26 may contribute to malignant phenotypes of glioma.

Primary erythrocytosis in a Japanese black calf: a case report.

An 8-month-old Japanese Black heifer with severe erythropoietic symptoms was subjected to clinical, histological and cytological examinations. During the 1 month clinical observation period, severe increases in RBC count, packed cell volume and haemoglobin concentration were observed. The plasma erythropoietin (Epo) concentration of the heifer (20.7 mIU/ml) was similar to that observed in normal control heifers. Blood gas examinations of the arterial and venous blood revealed low levels of partial pressure O(2) (PaO(2)), partial pressure CO(2) (PaCO(2)) and O(2) saturation (SaO(2)), while the blood pH was within the normal range. Gross lesions could not be detected. However, microscopic observation revealed severe proliferation of erythroblasts in the bone marrow and in the spleen without evidence of neoplastic changes. Based on these clinical and pathological examinations, we diagnosed the heifer as being the first case of primary erythrocytosis in Japanese Black cattle.

Molecular monitoring of bleomycin-induced pulmonary fibrosis by cDNA microarray-based gene expression profiling.

Pulmonary fibrosis is a progressive disorder whose molecular pathology is poorly understood. Here we developed an in-house cDNA microarray ("lung chip") originating from a lung-normalized cDNA library. By using this lung chip, we analyzed global gene expression in a murine model of bleomycin-induced fibrosis and selected 82 genes that differed by more than twofold intensity in at least one pairwise comparison with controls. Cluster analysis of these selected genes showed that the expression of genes associated with inflammation reached maximum levels at 5 days after bleomycin administration, while genes involved in the development of fibrosis increased gradually up to 14 days after bleomycin treatment. These changes in gene expression signature were well correlated with observed histopathological changes. The results show that microarray analysis of animal disease models is a powerful approach to understanding the gene expression programs that underlie these disorders.

Effect of dietary cabbage fermentation extract and young barley leaf powder on immune function of Sprague-Dawley rats.

We investigated dietary effects of cabbage fermentation extract (CFE) and young barley leaf powder (YBLP) on rat immune functions. Male Sprague-Dawley rats of 4 wk age were fed for 3 wk diets containing these samples at 0.1 or 1% level. After the feeding period, serum IgG level was significantly higher in the rats fed 1% CFE. IgG productivity of spleen lymphocytes was enhanced dose-dependently in both groups of CFE and YBLP. Furthermore, IgG productivity of mesenteric lymph node (MLN) lymphocytes was approximately 2 times higher in the rats fed 1% CFE diet than in the control ones. IgA productivity of MLN lymphocytes tended to increase in both of CFE and YBLP groups. From these results, it was suggested that dietary CFE and YBLP reinforced Ig productivity in both systemic and intestinal immune systems. Moreover, CFE feeding tended to enhance the production of TNF-alpha by spleen lymphocytes. In spleen phospholipids, the level of arachidonic acid, a substrate for inflammatory lipid mediators, was not affected by CFE or YBLP feeding.

The mechanism of cell death in human cultured colon adenocarcinoma cell line COLO 201 induced by beta-D-N-acetylglucosaminyl-p-nitrophenol.

COLO 201, human colon adenocarcinoma cells were incubated with artificial primers, p-nitrophenyl-glycoside derivatives at 1.0 mmol (mM) in the medium containing 10% fetal bovine serum to detect sugar chain elongation. However, when p-nitrophenyl-beta-N-acetylglucosamine (beta-GlcNAc-PNP) was added, the medium changed color to yellow and the cells were dead. To explain this finding, the cells were incubated with 1.0 mM each of beta-GlcNAc-PNP and 4-methylumbelliferyl-beta-N-acetylglucosamine, then the number of living cells was measured in a time course. In beta-GlcNAc-PNP, the living cells were decreased at 24 hours. The cells were survived with N-acetylglucosamine, whereas in the presence of p-nitrophenol (PNP) the living cells were decreased. It was suggested that PNP released from beta-GlcNAc-PNP induced the cell death. Activity of beta-D-N-acetylglucosaminidase was detected in fetal bovine serum. It was shown that PNP induced the cell death in time-and-dose dependent manner. Genomic DNA from COLO 201 analyzed by agarose gel electrophoresis was fragmentated. PNP analogues were tested for toxicity, and the results suggested that the phenolic OH-group linked to benzene ring and nitro-group linked to the structure in para-form (PNP) was the most effective.

[Female carrier of Duchenne muscular dystrophy presenting with secondary dilated cardiomyopathy: a case report].

A 48-year-old female carrier of Duchenne muscular dystrophy had developed congestive heart failure but had no skeletal muscle symptoms. She was admitted to our hospital complaining of palpitation in December 1998. Her three sons had Duchenne muscular dystrophy. Neurological examination was unremarkable with no evidence of muscle weakness. Serum creatine kinase level was slightly increased. Echocardiography showed severe left ventricular dysfunction. Coronary angiography showed no abnormalities. Left ventriculography showed generalized hypokinesis and left ventricular ejection fraction was 28%. Dystrophin immunostaining of the skeletal muscle biopsy specimen showed a mosaic pattern. The dystrophin negative fibers were scattered among positive fibers. Cardiomyopathy is the only clinical manifestation of dystrophin gene mutation in carriers. Beta-blocker therapy(carvedilol 5 mg/day) was effective in this patient.

Changes in glycosaminoglycan, galactosyltransferase-I, and sialyltransferase during rat liver regeneration.

After partial hepatectomy, the liver is capable of complete restoration to its normal size. The extracellular matrix, which surrounds the cells, plays important roles in this regeneration. Glycosaminoglycans (GAGs), which are components of the extracellular matrix, interact with several other matrix components and growth factors, and are involved in hepatocyte growth. In this study, the content of heparan sulfate, a major GAG in rat liver, reached a minimum at 12 hours after partial hepatectomy. Galactosyltransferase-I activity, related to the synthesis of GAGs, and sialyltransferase activity, related to the synthesis of glycoconjugates, reached a minimum at 6 hours. The serum and liver contents of hyaluronic acid reached a maximum at 1 day and returned gradually to their preoperative levels. These results suggest that polysaccharide synthesis was decreased in the Golgi apparatus of hepatocytes at the beginning of regeneration, and that hyaluronic acid degradation decreased in the lysosomes of hepatocytes. The ability to synthesize polysaccharides recovered ahead of the ability to degrade hyaluronic acid. The changes in these GAGs with time in the early regeneration period might play an important role in organ regeneration.

Effects of ATP on regulation of galactosyltransferase-I activity responsible for synthesis of the linkage region between the core protein and glycosaminoglycan chains of proteoglycans.

We report that ATP enhances the activity of galactosyltransferase-I, which synthesizes the linkage region between glycosaminoglycan chains and the core proteins of proteoglycans. The enzyme activity in cell-free fractions prepared from cultured human skin fibroblasts was measured by high-performance liquid chromatographic detection of galactosyl-xylosyl-(4-methylumbelliferone) produced from 4-methylumbelliferyl-beta-D-xyloside used as an acceptor. ATP at 2 mM increased the enzyme activity by about 60% in the 110 x g supernatant of the cell homogenate, but not in the supernatant or precipitate fractions obtained by 100,000 x g centrifugation. When both fractions (the 100,000 x g supernatant and precipitate) were mixed, the additional ATP increased the enzyme activity. This increase was canceled by heat treatment or trypsin digestion of the 100,000 x g supernatant. In addition, the 100,000 x g precipitate, which was prepared from the 110 x g supernatant preincubated with ATP, exhibited increased activity, and this increase was abolished by alkaline phosphatase treatment. These results suggest that a protein kinase in the 100,000 x g supernatant activates galactosyltransferase-I activity.

Pedunculated basal cell epithelioma which is not Pinkus tumor.

A 33-year-old female with pedunculated basal cell epithelioma was reported. She had noticed a cutaneous tumor on the scalp for two years before admission. It developed gradually and clinically resembled fibroma or pigmented nevus. Total resection was performed, and its histopathology revealed the solid or cystic type of basal cell epithelioma.

Genomic analysis of a mouse model of immunoglobulin A nephropathy reveals an enhanced PDGF-EDG5 cascade.

The molecular mechanism of immunoglobulin A nephropathy (IgAN), the most common primary renal glomerular disease worldwide, is unknown. HIGA (high serum IgA) mouse is a valid model of IgAN showing almost all of the pathological features, including mesangial cell proliferation. Here we elucidate a pattern of gene expression associated with IgAN by analyzing the diseased kidneys on cDNA microarrays. In particular, we showed an enhanced expression of several genes regulating the cell cycle and proliferation, including growth factors and their receptors, as well as endothelial differentiation gene-5 (EDG5), a receptor for sphingosine 1-phosphate (SPP). One of the growth factors, platelet-derived growth factor (PDGF) induces a marked upregulation of EDG5 in proliferative mesangial cells, and promotes cell proliferation synergistically with SPP. The genomic approach allows us to identify families of genes involved in a process, and can indicate that enhanced PDGF-EDG5 signaling plays an important role in the progression of IgAN.

Structural varieties of small proteoglycans in human spinal ligament.

Three types of small proteoglycan were purified from human spinal ligaments by ultracentrifugation, ion-exchange chromatography, gel-chromatography, and hydrophobic chromatography. Two of them were identified as decorin and biglycan, and the other was thought to be a decorin-subtype. Molecular sizes of decorin and decorin-subtype were both 85 kDa, and that of biglycan was 200 kDa. N-Terminal amino acid sequence of decorin-subtype corresponded with that of decorin, although it was different from decorin in terms of composition of amino acids and glycosaminoglycan chains, and reactivity with anti-human decorin antibody. The ratios of chondroitin sulfate to dermatan sulfate contained in the three proteoglycans were different, and the location of that in glycosaminoglycan chains was also thought to be different. It was demonstrated that three types of proteoglycan which are structurally different are present in extracellular matrix.

Chimeric glycosaminoglycan oligosaccharides synthesized by enzymatic reconstruction and their use in substrate specificity determination of Streptococcus hyaluronidase.

A method was developed for the reconstruction of glycosaminoglycan (GAG) oligosaccharides using the transglycosylation reaction of an endo-beta-N-acetylhexosaminidase, testicular hyaluronidase, under optimal conditions. Repetition of the transglycosylation using suitable combinations of various GAGs as acceptors and donors made it possible to custom-synthesize GAG oligosaccharides. Thus we prepared a library of chimeric GAG oligosaccharides with hybrid structures composed of disaccharide units such as GlcA-GlcNAc (from hyaluronic acid), GlcA-GalNAc (from chondroitin), GlcA-GalNAc4S (from chondroitin 4-sulfate), GlcA-GalNAc6S (from chondroitin 6-sulfate), IdoA-GalNAc (from desulfated dermatan sulfate), and GlcA-GalNAc4,6-diS (from chondroitin sulfate E). The specificity of the hyaluronidase from Streptococcus dysgalactiae (hyaluronidase SD) was then investigated using these chimeric GAG oligosaccharides as model substrates. The results indicate that the specificity of hyaluronidase SD is determined by the following restrictions at the nonreducing terminal side of the cleavage site: (i) at least one disaccharide unit (GlcA-GlcNAc) is necessary for the enzymatic action of hyaluronidase SD; (ii) cleavage is inhibited by sulfation of the N-acetylgalactosamine; (iii) hyaluronidase SD releases GlcA-GalNAc and IdoA-GalNAc units as well as GlcA-GlcNAc. At the reducing terminal side of the cleavage site, the sulfated residues on the N-acetylgalactosamines in the disaccharide units were found to have no influence on the cleavage. Additionally, we found that hyaluronidase SD can specifically and endolytically cleave the internal unsulfated regions of chondroitin sulfate chains. This demonstration indicates that custom-synthesized GAG oligosaccharides will open a new avenue in GAG glycotechnology.

Enzymatic reconstruction of dermatan sulfate.

We investigated the enzymatic reconstruction of dermatan sulfate (DS) using the transglycosylation reaction of testicular hyaluronidase. First, in order to insert the IdoA-GalNAc disaccharide unit into chondroitin sulfate chains consisting of GlcA-GalNAc disaccharide units, desulfated DS as a donor and pyridylaminated (PA) chondroitin 6-sulfate (Ch6S) hexasaccharide as an acceptor were subjected to a transglycosylation reaction using testicular hyaluronidase. The products were analyzed by HPLC, mass spectrometry, and enzymatic digestions, and the results indicated that one of the products was IdoA-GalNAc-(GlcA-GalNAc6S)(3)-PA. Next, when the resulting PA-Ch6S (hexa-)desulfated DS (di-)octasaccharide was used as an acceptor and chondroitin as a new donor, a decasaccharide having a GlcA-GalNAc-IdoA-GalNAc-(GlcA-GalNAc6S)(3) sequence was reconstructed. Using suitable combinations of donors and acceptors, it was possible to custom synthesize DS having any IdoA sequence as its uronic acid component. It is likely that application of this system would facilitate artificial reconstruction of variant DS having different specific functions.

Interaction between collagens and glycosaminoglycans investigated using a surface plasmon resonance biosensor.

The interactions of glycosaminoglycans with collagens and other glycoproteins in extracellular matrix play important roles in cell adhesion and extracellular matrix assembly. In order to clarify the chemical bases for these interactions, glycosaminoglycan solutions were injected onto sensor surfaces on which collagens, fibronectin, laminin, and vitronectin were immobilized. Heparin bound to type V collagen, type IX collagen, fibronectin, laminin, and vitronectin; and chondroitin sulfate E bound to type II, type V, and type VII collagen. Heparin showed a higher affinity for type IX collagen than for type V collagen. On the other hand, chondroitin sulfate E showed the highest affinity for type V collagen. The binding of chondroitin sulfate E to type V collagen showed higher affinity than that of heparin to type V collagen. These data suggest that a novel characteristic sequence included in chondroitin sulfate E is involved in binding to type V collagen.

Acute toxicity of an anti-Fas antibody in mice.

By histopathologic examination of various organs in 3 normal strains, C3H/HeN, ICR, and DBA/1J, of mice treated intravenously once with anti-Fas antibody (Jo2), we failed to determine any target organ, except the liver, responsible for the acute lethality induced by the Fas/anti-Fas antibody interaction. However, we could show the presence of Fas-mediated apoptosis in other organs aside from the liver and normal mouse strain differences in susceptibility to anti-Fas antibody. Among these strains, C3H/HeN was the most susceptible to the antibody, followed by ICR and DBA/1J. We observed Fas-mediated apoptosis in the liver, spleen, thymus, lymph nodes, Peyer's patch, intestine, skin, coagulation glands, ovary, uterus, and vagina in all 3 strains and additionally in the epididymides and seminal vesicles in the DBA/1J strain. We also demonstrated that Fas-mediated apoptosis of small lymphocytes in the mantle zone of splenic lymphatic follicles preceded that of the hepatocytes or thymic cells. Since cellular damage was most severe in the liver among all the apoptotic organs in the 3 mouse strains, liver injury induced by anti-Fas antibody is speculated to play a significant role in the death.