Polymorphisms in the SOD2 and HLA-DRB1 genes are associated with nonfamilial idiopathic dilated cardiomyopathy in Japanese.

To reveal genetic risk factors of nonfamilial idiopathic cardiomyopathy (IDC) in Japanese, polymorphisms in the SOD2 and HLA-DRB1 genes were investigated in 86 patients and 380 healthy controls. There was a significant excess of homozygotes for the V allele [Val versus Ala (A allele), a polymorphism in the leader peptide of manganese superoxide dismutase at position 16] of the SOD2 gene in the patients compared with the controls (87.2% versus 74.7%, odds ratio = 2.30, p = 0.013, pc < 0.03), and a significant increase in the frequency of HLA-DRB1*1401 in the patients was confirmed (14.0% vs 4.5%, odds ratio = 3.46, p = 0.001, pc < 0.03). A two-locus analysis suggested that these two genetic markers (SOD2-VV genotype and DRB1*1401) may play a synergistic role in controlling the susceptibility to nonfamilial IDC. In addition, processing efficiency of Val-type SOD2 leader peptide in the presence of mitochondria was siginificantly lower than that of the Ala-type by 11 +/- 4%, suggesting that this lower processing efficiency was in part an underlying mechanism of the association between the SOD2-VV genotype and nonfamilial IDC.     

Preclinical Validation of Talaporfin Sodium-Mediated Photodynamic Therapy for Esophageal Squamous Cell Carcinoma

Photodynamic therapy (PDT) kills cancer cells via a photochemical reaction mediated by an oncotropic photosensitizer. Herein, we performed an experimental preclinical study to validate the anti-tumour effect of talaporfin sodium-mediated PDT (t-PDT) for esophageal squamous cell carcinoma (ESCC) cells. We used human ESCC cells derived from various differentiation grades or resistant to 5-fluorouracil (5-FU). The cytotoxic effect of t-PDT was determined by evaluating cell viability, apoptosis and generation of reactive oxygen species (ROS) and DNA double-strand breaks. Furthermore, the anti-tumour effect of t-PDT was assessed using an anchorage-independent cell-growth assay and xenograft transplantation models. t-PDT induced potent cytotoxicity in ESCC cells independent of their differentiation grade or 5-FU resistance. Moreover, t-PDT induced robust apoptosis, as indicated by cell shrinkage, perinuclear vacuolization, nuclear fragmentation and induction of annexin V-positive cells. This apoptotic response was accompanied by concurrent activation of ROS, and induction of DNA double-strand breakage. Importantly, t-PDT suppressed efficiently anchorage-independent cell growth as well as ESCC-xenografted tumor formation. In aggregate, t-PDT showed anti-tumor potential for ESCC cells with various histological grades or chemoresistance, providing a novel translational rationale of t-PDT for the treatment of ESCC.     

Effect of Parietal Transcranial Magnetic Stimulation on Spatial Working Memory in Healthy Elderly Persons - Comparison of Near Infrared Spectroscopy for Young and Elderly

In a previous study, we succeeded in improving the spatial working memory (WM) performance in healthy young persons by applying transcranial magnetic stimulation (TMS) to the parietal cortex and simultaneously measuring the oxygenated hemoglobin (oxy-Hb) level using near-infrared spectroscopy (NIRS). Since an improvement in WM was observed when TMS was applied to the right parietal cortex, the oxy-Hb distribution seemed to support a model of hemispheric asymmetry (HA). In the present study, we used the same study design to evaluate healthy elderly persons and investigated the effect of TMS on WM performance in the elderly, comparing the results with those previously obtained from young persons. The application of TMS did not affect WM performance (both reaction time and accuracy) of 38 elderly participants (mean age  = 72.5 years old). To investigate the reason for this result, we conducted a three-way ANOVA examining oxy-Hb in both young and elderly participants. For the right parietal TMS site in the elderly, TMS significantly decreased the oxy-Hb level during WM performance; this result was the opposite of that observed in young participants. An additional three-way ANOVA was conducted for each of the 52 channels, and a P value distribution map was created. The P value maps for the young participants showed a clearly localized TMS effect for both the WM and control task, whereas the P map for the elderly participants showed less significant channels and localization. Further analysis following the time course revealed that right-side parietal TMS had almost no effect on the frontal cortex in the elderly participants. This result can most likely be explained by age-related differences in HA arising from the over-recruitment of oxy-Hb, differentiation in the parietal cortex, and age-related alterations of the frontal-parietal networks.     

Essential Contribution of CD4+ T Cells to Antigen-Induced Nasal Hyperresponsiveness in Experimental Allergic Rhinitis

Nasal hyperresponsiveness (NHR) is a characteristic feature of allergic rhinitis (AR); however, the pathogenesis of NHR is not fully understood. In this study, during the establishment of an experimental AR model using ovalbumin-immunized and -challenged mice, augmentation of the sneezing reaction in response to nonspecific proteins as well as a chemical stimulant was detected. Whether NHR is independent of mast cells and eosinophils was determined by using mast cell- and eosinophil-deficient mice. NHR was suppressed by treatment with anti-CD4 antibody, suggesting the pivotal contribution of CD4⁺ T cells. Furthermore, antigen challenge to mice to which in vitro-differentiated Th1, Th2, and Th17 cells but not naïve CD4⁺ T cells had been adoptively transferred led to the development of equivalent NHR. Since antigen-specific IgE and IgG were not produced in these mice and since antigen-specific IgE-transgenic mice did not develop NHR even upon antigen challenge, humoral immunity would be dispensable for NHR. CD4⁺ T cells play a crucial role in the pathogenesis of AR via induction of NHR, independent of IgE-, mast cell-, and eosinophil-mediated responses.     

The development of porcine zona pellucida using monoclonal antibodies: II. Electron microscopy

Following our previous study on the immunohistochemistry of porcine zonae pellucidae (ZP), we undertook the present study to localize the components of the ZP with immunoelectron microscopy, using three types of anti-porcine-ZP monoclonal antibodies (Mabs), named STA-1, STA-2, and STA-3. Some organelles of the oocyte were seen to react with STA-2 and STA-3 prior to ZP formation. As soon as a follicle began to mature, STA-2 and STA-3 reacted with the perinuclear space and the endoplasmic reticular membrane of the oocyte. The follicle first reacted with STA-1 at the secondary follicle stage. At this stage, the positive reaction involved the follicular cell layer as well as the oocyte and ZP. Positive reaction was scattered within and limited to the interfollicular cell space and was never found in the cytoplasm of follicular cells. At the antral follicle stage, the oocyte was surrounded by a thick, electron-dense ZP. A strong reaction was observed in the outer layer, but no significant reaction occurred in the inner layer. The convex and ragged outer margin of the ZP was characterized by the strongest reaction.     

Purification and characterization of a neutral protease from rat-liver cytosolic fraction

Rat liver cytosol contains a neutral protease which degrades acetylated hemoglobin and some urea-denatured proteins maximally at pH 7.5. The enzyme was purified to homogeneity by conventional chromatographic techniques. It appears to be a metalloprotease since it is inhibited by EDTA and o-phenanthroline, the metal-depleted enzyme can be reactivated by Co2+, Zn2+, Mn2+, or Mg2+, and it is not inhibited by reagents specific for carboxyl, seryl, or thiol proteases. The enzyme has an apparent molecular weight of 200,000 as determined on Sephacryl S-200 column chromatography, and electrophoresis in sodium dodecyl sulfate showed 3 protein bands corresponding to the molecular weights of 110,000, 74,000, and 40,000.     

Pistil hyperplasia in rice spikelets as affected by heat stress

Summary Sexual organogenesis in spikelets of rice (Oryza sativa L. cv Kinmaze) affected by heat stress was investigated using SEM and stereo-microscopy. Of the 243 spikelets dissected, 55.6% developed pistil hyperplasia, i.e., proliferated female organs or tissues, including multiple stigmata and/or ovaries, outgrowth of swollen parenchymatous tissues from inside the ovule, and differentiation of trichomes from ovary epidermis. Conversely, 7% of the spikelets exhibited stamen hypoplasia, represented by a decrease in the number of stamens, and only 3.7% of the spikelets showed hyperplasia, represented by an increase in the number of stamens. The morphological and structural development of the anther was disturbed, and microsporogenesis was inhibited. The shape of the anther was altered, though not perfectly, into the form of an ovary; the lemma and palea changed in form and ultimately resembled each other in shape and size. All of these changes in structure are more or less similar to those that usually result in rice spikelets subjected to cold and other environmental stresses. It was therefore concluded that rice plants show similar responses in sex differentiation in the spikelet under various environmental stresses.