The pathogenesis of spinal cord involvement in dengue virus infection

To investigate the mechanisms of dengue (DEN) virus transmission within the spinal cord, severe combined immunodeficient mice were intracerebrally inoculated with DEN virus type 2. After inoculation, a high virus titer and antigens were detected in the brain and spinal cord. At early stages of the infection, ultrastructural examinations showed that a few virions were present in the cytoplasm of ependymal cells lining the central canal. As the infection progressed, virions were observed in the lumen of the rough endoplasmic reticulum (RER), RER-derived vesicles and the Golgi region of infected neurons. These data suggest that the inoculated DEN virus might spread to the neurons of the spinal cord via the cerebral spinal fluid and cause several neuronal pathological responses. Moreover, DEN virus was also observed in myelinated and unmyelinated nerve fibers and typical neuronal synapses. Some virion-containing vesicles appeared to be fused with the membrane of presynapses, indicating that neuron-to-neuron transport of DEN virus might occur in the spinal cord. Additionally, anterior, lateral and posterior horns of the spinal cord exhibited different numbers of the positive neurons and different staining intensities of the DEN antigen during the infection. This difference likely represents variation of susceptibility to the DEN virus among the neurons of the spinal cord.     

Clinical significance of expression of membrane type 1 matrix metalloproteinase and matrix metalloproteinase-2 in human head and neck squamous cell carcinoma

Three different membrane-type matrix metalloproteinases (MT-MMPs) activate in vitro the latent form of matrix metalloproteinase-2 (MMP-2), which is one of the key proteinases in invasion and metastasis of various cancers. We examined the mRNA expression of MT1, 2, and 3-MMPs and MMP-2 in cell lines of head and neck squamous cell carcinoma (HNSCC) and quantitated the relative expression levels in human HNSCC tissues by Northern blotting. The tissue localization of MT1-MMP and MMP-2 was determined by immunohistochemistry and in situ hybridization. Their implications in clinicopathologic factors were statistically evaluated. All cell lines examined consistently expressed MT1-MMP and MMP-2, but not MT2, 3-MMP. In the clinical specimens, there was a significant correlation in coexpression of messenger of RNA (P = .0005) and colocalization by immunohistochemistry (P < .0001) for MT1-MMP and MMP-2. Relative mRNA expression levels of MT1-MMP and MMP-2 in the carcinoma tissues were significantly higher than those of the control tissues (P = .0045 and P = .0122, respectively). Both mRNA expression level and immunopositivity of MT1-MMP significantly correlated with lymph node metastasis (P = .0081 and P = .0193, respectively), which was confirmed by multivariate logistic regression analysis. Immunoreaction of MT1-MMP and its mRNA expression were observed in both carcinoma cells and stromal cells. The localization of MMP-2 closely corresponded to that of MT1-MMP. These observations suggest that MT1-MMP possesses a role as a determinant of lymph node metastasis in HNSCC, and that concurrent expression of MT1-MMP and MMP-2 are involved in progression of HNSCC.     

Neovascularization of transplanted central nervous tissue suspensions: an immunohistochemical study with laminin

Neovascularization of the dissociated central nervous tissue transplanted into the lateral ventricle of the rat was studied using laminin immunohistochemistry. A very high immunoreactive response to laminin was demonstrated in the presumably newly formed vessels within the transplants and the graft-host borders. The growing tips and fine spike-like sprouts called 'streamers' were also highly stained with laminin immunoreactivity. In contrast, laminin immunoreactivity was negligible in the vessels in the host brain. Therefore, these results indicate that laminin may be utilized as a marker for the newly formed vessels in neural transplantations.     

Blood endotyping distinguishes the profile of vitiligo from that of other inflammatory and autoimmune skin diseases

1. Download : Download high-res image (180KB)
2. Download : Download full-size image

     

Cartilage regeneration using slow release of bone morphogenetic protein-2 from a gelatin sponge to treat experimental canine tracheomalacia: a preliminary report

We investigated whether saber sheath-type tracheomalacia could be treated by the slow release of bone morphogenetic protein (BMP)-2 from a gelatin sponge. A 1 cm gap was made in the middle portion of each of 10 consecutive tracheal cartilage rings in the canine cervix (control group, n = 3), then a gelatin sponge containing 12 microg of BMP-2 solution was implanted in the gap (12 microg group, n = 3). In another group (120 microg + P group, n = 3), the implanted gelatin sponge contained 120 microg of BMP-2 solution, and the gap was covered with periosteum. All of the control dogs developed saber sheath-type tracheomalacia, whereas tracheomalacia was not observed in the 12 microg and 120 microg + P groups. In the 12 microg group, fibrous cartilage was observed at the ends of the cartilage stumps. In the 120 microg + P group, newly formed bone and cartilage were observed to form a bridge between the cartilage stumps. The regeneration of cartilage or bone induced by the slow release of BMP-2 from a gelatin sponge might be useful for treatment of tracheomalacia.     

Three-dimensional two-layer collagen matrix gel culture model for evaluating complex biological functions of monocyte-derived dendritic cells

Dendritic cell-like cells (Mo-DCs) generated from peripheral blood monocytes with interleukin-4 (IL-4) and granulocyte-macrophage colony-stimulating factor (GM-CSF) have been used as tools to treat cancer patients (DC-vaccines). Because Mo-DCs have multiple antigen presentation-related functions, including phagocytosis, migration, cytokine production, and T cell stimulation, establishment of a method for simultaneously evaluating the various functions of Mo-DCs is important. We developed a new in vitro three-dimensional two-layer collagen matrix culture model that consists of a collagen gel containing Mo-DCs as the lower layer and a collagen gel containing necrotic GCTM-1 tumor cells and/or T cells as the upper layer. We used this system to observe simultaneously multiple functions of Mo-DCs by phase-contrast or fluorescence microscopy and to assess IL-12 secretion during more than 2 weeks of culture. We also observed interactions between Mo-DCs and necrotic GCTM-1 or T cells on an individual cell basis by time-lapse videomicroscopy. In addition, we collected Mo-DCs from the collagen gels by collagenase treatment and analyzed the expression of antigen presentation-related molecules such as HLA-DR, CD80, CD83, and CD86 on Mo-DCs. This model may be a useful tool for evaluation of the various functions of Mo-DCs used as DC vaccines and for studies of the complex behaviors of Mo-DCs in vivo.     

Posthepatectomy hepatitis shortens tumor-free intervals in hepatitis C virus-associated hepatocellular carcinoma patients

In hepatitis C virus (HCV)-associated hepatocellular carcinoma (HCC), serum alanine aminotransferase (ALT) is frequently sustained on a high level after hepatectomy, with the formation of recurrent HCC tumors during follow-up periods. We investigated whether or not postoperative serum ALT level affects the interval before recurrence in hepatitis C virus-associated HCC. The subjects studied were 50 hepatectomized HCC patients who were HCV-Ab(+), and underwent a curable surgery in our Hospital from June 1990 to December 1999. We assessed the significance of the postoperative serum ALT level affecting tumor-free survival rates, as compared with other clinicopathological parameters, using univariate and multivariate Cox proportional hazard analysis. Thereafter, tumor-free and overall survival rates after hepatectomy were compared between high and low ALT groups, using Kaplan-Meier plotting and a log-rank test. The factor of ALT levels (a high or low ALT group) was most strongly associated with a tumor-free survival rate. Both tumor-free and overall survival rates were significantly poorer in the high ALT group than in the low ALT group among HCV-associated HCC cases (p<0.05). The results in this study suggest that postoperative hepatitis, which is indicated by sustained high ALT levels, may shorten the interval before recurrence in HCV-associated HCC. We should take care to control postoperative hepatitis to improve the prognoses of HCV-associated HCC cases.     

CYTOLOGICAL and ULTRASTRUCTURAL CHARACTERISTICS OF DNA SYNTHESIZING MESOTHELIAL CELLS IN PLEURAL EFFUSION

Cytologic examination of 3H-thymidine-labeled mesothelial cells in the pleural fluid revealed that single and small-sized cells with slight basophilic cytoplasm scarcely stainable by PAS and colloidal iron are in the DNA-synthetic phase and that these are exfoliating cells from the pleural surface. While abnormal labeling in a few arranged and binuclear cells suggesting accelerated or disturbed mesothelial mobilization was frequently found in congestive cardiac failure, liver cirrhosis, and uremia, it never occurred in single and large-sized activated cells possessing rich PAS-positive granules, cells in large clusters or sheet-like arrangements, or multinuclear giant cells. Transmission electron microscopical observation of these labeled cells proved that a smooth cellular surface and scant intracytoplasmic organelles, by which undifferentiated cells are generally characterized, are essential for DNA-synthesizing mesothelial cells. Probably as a result of some pleural irritation, surface lining cells immediately enter the cell cycle and at once revert to an undifferentiated form capable of DNA synthesis, after which they may be released as a single form, and differentiate and transform into mature, activated cells with a bleb-like surface structure or microvilli, and finally may proliferate in the fluid. ACTA PATHOL. JPN. 36: 1279–1296, 1986.     

Prevalence of Japanese cedar pollinosis among schoolchildren in Japan

BACKGROUND: Japanese cedar pollinosis is an important allergic rhinoconjunctivitis in Japan in spring. We investigated the relationship between the amount of pollen in the air and the prevalence of the disease and sensitization to Japanese cedar pollen in this ecological study. METHODS: The IgE antibody to Japanese cedar pollen (JCP-IgE) was determined in human serum and rhinoconjunctival symptoms were surveyed in 407-510 children in May or June every year from 1995 to 2001. Japanese cedar pollinosis was defined as being JCP-IgE >or=1.5 IU/ml and having any rhinoconjunctival symptom lasting 3 weeks or longer in March or April. RESULTS: Prevalence rates of Japanese cedar pollinosis were 13.8-22.9%. Prevalence rates of being JCP-IgE >or=1.5 IU/ml were 39.0-50.1%, and those of being JCP-IgE >or=15.01 IU/ml were 11.4-23.2%. All prevalence rates were significantly related to the amount of pollen in the air. The proportion of subjects with rhinoconjunctival symptoms was relatively constant in each stratum of low JCP-IgE levels (<0.35, 1.50-2.99, 3.0-14.9 IU/ml). CONCLUSION: High exposure to Japanese cedar pollen was associated with higher levels of JCP-IgE antibody and a high prevalence of Japanese cedar pollinosis. The relationship between the level of JCP-IgE and the proportion of subjects with symptoms was relatively constant.