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Purpose A peripapillary detachment in pathologic myopia (PDPM) appears as a yellowish-orange lesion around the optic disc in highly myopic eyes. We report a case in which a macular retinal detachment (RD) accompanied a PDPM. Method A case report was used in this study. Results The right eye in a 48-year-old man showed a macular RD and a PDPM. Fluorescein fundus angiography showed no dye leakage, suggestive of an optic pit within the optic disc. Optical coherence tomography (OCT) examination revealed that there was a full-thickness tissue defect in the retina overlying PDPM, the vitreous cavity was connected to PDPM through this defect, and the PDPM was continuous with the RD through the subretinal path at the conus area. Conclusions These findings suggest that this eye had a macular RD associated with a PDPM, and eyes with a PDPM might be at risk of developing macular RD.

Mitotic arrest–deficient protein 1 (MAD1) is a component of the mitotic spindle assembly checkpoint. We have created a knockout mouse model to examine the physiologic consequence of reduced MAD1 function. Mad1+/− mice were successfully generated, but repeated paired mating of Mad1+/− with Mad1+/− mice failed to produce a single Mad1−/− animal, suggesting that the latter genotype is embryonic lethal. In aging studies conducted for >18 months, Mad1+/− mice compared with control wild-type (wt) littermates showed a 2-fold higher incidence of constitutive tumors. Moreover, 42% of Mad1+/− (P < 0.03), but 0% of wt, mice developed neoplasia after treatment with vincristine, a microtubule depolymerization agent. Mad1+/− mouse embryonic fibroblasts (MEF) were found to be more prone than wt cells to become aneuploid; Mad1+/−, but not wt, MEFs produced fibrosarcomas when explanted into nude mice. Our results indicate an essential MAD1 function in mouse development and correlate Mad1 haploinsufficiency with increased constitutive tumors. [Cancer Res 2007;67(1):160–6]

Background: Mutations in the human NOD2/CARD15 gene have been associated with Crohn's disease and Blau syndrome. The objective of the present study was to clone the murine form of NOD2 and characterize its tissue distribution, function and response to inflammatory stimuli. Methods: Murine NOD2 was isolated using anchored polymerize chain reaction (PCR). Sequence analysis confirmed the identification of full-length cDNA representing the murine NOD2 gene. Using this sequence to search a Mus musculus supercontig database, NOD2 genomic DNA was identified. NOD2 was transfected into human embryonic kidney (HEK) cells and nuclear factor kappa B (NF-κB) activation was measured using a reporter assay. Tissue distribution and changes in transcription in mouse monocytes in response to inflammatory stimuli was determined by real time PCR. Results: The NOD2 gene spans 39 KB and contains 12 coding exons on chromosome 8. Expression of mouse NOD2 into HEK cells resulted in NF-κB activation. NOD2 was found to be expressed in all mouse tissues analyzed except skin, with highest levels in lung, thymus and spleen. NOD2 mRNA levels increased greater than two-fold in a monocyte cell line in response to lipopolysaccharide, lipoteichoic acid, interferon-g and tumor necrosis factor-α. Conclusions: Common structural and functional features between human and mouse NOD2 were identified. This should allow for development of relevant animal models to evaluate the role of NOD2 in chronic inflammatory disorders.

In eukaryotes, the mitotic spindle assembly checkpoint provides a monitor for the fidelity of chromosomal segregation. In this context, the mitotic arrest deficiency protein 2 (MAD2) censors chromosomal mis-segregation by monitoring microtubule attachment/tension, a role that requires its attachment to kinetochores. Studies in yeast have shown that binding of MAD1 to MAD2 is important for the checkpoint function of the latter. The interactions between human MAD1 (hsMAD1) and human MAD2 (hsMAD2) have, however, remained poorly characterized. Here we report that two leucine zipper domains (amino acids 501-522 and 557-571) in hsMAD1 are required for its contact with hsMAD2. Interestingly, in several cancer cell lines, we noted the frequent presence of a coding single nucleotide Arg to His polymorphism at codon 558 located within the second leucine zipper of hsMAD1. We found that hsMAD1H558 is less proficient than hsMAD1R558 in binding hsMAD2 and in enforcing mitotic arrest. We also document a first example of loss-of-heterozygosity for a spindle checkpoint gene (at the hsMAD1 558 locus) in a human breast cancer. Based on our findings, it is possible that hsMAD1H558 could be an at-risk polymorphism that contributes to attenuated spindle checkpoint function in human cells.

Human T-cell leukemia virus type I (HTLV-I) is the causative agent for adult T-cell leukemia (ATL). Molecularly, ATL cells have extensive aneugenic abnormalities that occur, at least in part, from cell cycle dysregulation by the HTLV-I-encoded Tax oncoprotein. Here, we compared six HTLV-I-transformed cells to Jurkat and primary peripheral blood mononuclear cells (PBMC) in their responses to treatment with microtubule inhibitors. We found that both Jurkat and PBMCs arrested efficiently in mitosis when treated with nocodazole. By contrast, all six HTLV-I cells failed to arrest comparably in mitosis, suggesting that ATL cells have a defect in the mitotic spindle assembly checkpoint. Mechanistically, we observed that in HTLV-I Tax-expressing cells human spindle assembly checkpoint factors hsMAD1 and hsMAD2 were mislocated from the nucleus to the cytoplasm. This altered localization of hsMAD1 and hsMAD2 correlated with loss of mitotic checkpoint function and chemoresistance to microtubule inhibitors.

To evaluate the efficacy and safety of infliximab administration in refractory uveoretinitis in Behçet's disease (BD).The subjects were 22 consecutive BD patients with refractory uveoretinitis treated with infliximab. Three patients dropped out from the therapy. The other 19 patients received the therapy for 6 months or longer. The efficacy was evaluated by the ocular attacks and best corrected visual acuity at remission in the 19 patients and the safety was evaluated in all 22 patients.The incidence of ocular attacks in the 6 months before and after the infliximab therapy were 3.0+/-2.6 and 0.4+/-1.1, respectively (p0.0005). Infliximab was very effective in 7 patients where no ocular attacks occurred throughout infliximab therapy, effective in 10 patients where ocular attacks was reduced, and non-effective in 2 patients. The vision was either improved or unchanged in all eyes at the 6th months therapy. Various adverse effects were seen in 14 patients, but non were serious.Infiximab therapy is effective in managing the refractory uveoretinitis in BD, but elucidation of the safety needs more patients and a longer follow-up period.

A 57-year-old man was admitted to our hospital because of persistent blurred vision for 5 months. He had opacity in the vitreous body and white lesions in the retina of the right eye. Although cytological examinations of the vitreous samples revealed Class II, the diagnosis of primary intraocular lymphoma (PIOL) was made by detecting both IgH rearrangement by PCR and an elevated ratio of IL-10/IL-6 concentration in the vitreous sample. Systemic examinations were performed simultaneously and no extra-ocular involvement was detected. Intravitreal methotrexate (MTX) injections were effective and the lesions disappeared following injections. Two months later (10 months after appearance of the right eye lesion), however, the same lesions appeared in the left eye. Cytological examinations of the left vitreous sample revealed Class V by detecting large abnormal lymphocytes. Although intravitreal MTX injections were also effective, central nervous system (CNS) involvement appeared only 2 months after the left eye lesions appeared. Open biopsy was performed and a diagnosis of diffuse large B-cell lymphoma was made. Despite starting with high-dose MTX, he died of CNS disease 1 year and 8 months after onset. Diagnosis of PIOL is difficult. Since local treatment was considered insufficient, an optimal treatment strategy for PIOL should be established.

Blau syndrome (BS) is a rare familial granulomatous disease manifested by uveitis, arthritis and skin rash. BS has recently been found to be associated with a distinctive mutation in NOD2, which encodes an intracellular toll-like receptor. We have compared host cell interaction with bacterial challenge in U937 cells expressing wild type human NOD2 (NOD2(wt)), mutant NOD2 (NOD2(Blau)), or a vector control (VC). The cells were incubated with Salmonella typhimurium. Intracellular uptake was assessed by harvesting the cells at different time points following invasion and quantitating the CFU, recovered after gentamicin treatment to kill extracellular organisms. Expression of TNF-alpha, TLR2 and TLR4 was determined by semi-quantitative RT-PCR under resting conditions and after stimulation by bacteria. Invasion of target cells with S. typhimurium was diminished in the presence of NOD2(Blau). Expression of TNF-alpha mRNA was enhanced following bacterial invasion in all cell lines but NOD2(Blau) was associated with a more rapid decline in TNF-alpha expression. Kinetics of intracellular clearance of bacteria indicated a relative defect in NOD2(Blau) compared to controls. This clearance defect may be related to the lack of sustained TNF-alpha seen in the early stages. These events were not related to differential TLR2 or TLR4 expression since there were no significant differences seen between the cell lines after bacterial stimulation. Our findings indicate that the NOD2 mutation associated with this syndrome alters host:microbial interaction, and this may have relevance to triggering factors in the ocular and joint inflammation seen in BS.

The HTLV-1 Tax oncoprotein rapidly induces cytogenetic damage which can be measured by a significant increase in the number of micronuclei (MN) in cells. Tax is thought to have both aneuploidogenic and clastogenic effects. To examine the cellular target for Tax which might mechanistically explain the clastogenic phenomenon, we tested the ability of Tax to induce MN in rodents cells genetically defective for either the Ku80 protein or the catalytic subunit of DNA protein kinase (DNAPKcs). We found that cells genetically mutated in Ku80 were refractory to Tax's induction of MN while cells knocked-out for DNAPKcs showed increased number of Tax-induced MN. Using a cytogenetic method termed FISHI (Fluorescent In Situ Hybridization and Incorporation) which measures the number of DNA-breaks in cells that contained unprotected 3'-OH ends, we observed that Tax increased the prevalence of unprotected DNA breaks in Ku80-intact cells, but not in Ku80-mutated cells. Taken together, our findings suggest Ku80 as a cellular factor targeted by Tax in engendering clastogenic DNA damage.

Background We present our experience in the diagnosis and treatment of spondylodiscitis. Methods 27 patients with spondylodiscitis were studied. There were 15 men and 12 women, with ages ranging from 26 to 85 years. Of the 27 cases, there were 21 patients with pyogenic spondylodiscitis, 6 patients with tuberculosis spondylodiscitis, and 8 patients with diabetes mellitus complication. Two patients presented with tetraparesis, 13 with paraparesis, and 1 with hemiparesis. Seventeen patients underwent surgical treatment, among whom surgical intervention with instrumentation was performed on 5 patients, and emergency operation was performed on 6 patients. Results Fourteen patients were judged as "excellent," 8 patients as "good," and 4 patients as "no change." One patient died because of infection by penicillin-resistant Staphylococcus pneumoniae . Conclusion It is very difficult to diagnose spondylodiscitis at the first medical examination. Most spondylodiscitis patients often first visit a department of internal medicine. We strongly recommend that all doctors, especially doctors examining diabetes mellitus patients daily, should be well informed of spondylodiscitis in order to improve its diagnosis.

In eukaryotes, the mitotic spindle assembly checkpoint provides a monitor for the fidelity of chromosomal segregation. In this context, the mitotic arrest deficiency protein 2 (MAD2) censors chromosomal mis-segregation by monitoring microtubule attachment/tension, a role that requires its attachment to kinetochores. Studies in yeast have shown that binding of MAD1 to MAD2 is important for the checkpoint function of the latter. The interactions between human MAD1 (hsMAD1) and human MAD2 (hsMAD2) have, however, remained poorly characterized. Here we report that two leucine zipper domains (amino acids 501-522 and 557-571) in hsMAD1 are required for its contact with hsMAD2. Interestingly, in several cancer cell lines, we noted the frequent presence of a coding single nucleotide Arg to His polymorphism at codon 558 located within the second leucine zipper of hsMAD1. We found that hsMAD1H558 is less proficient than hsMAD1R558 in binding hsMAD2 and in enforcing mitotic arrest. We also document a first example of loss-of-heterozygosity for a spindle checkpoint gene (at the hsMAD1 558 locus) in a human breast cancer. Based on our findings, it is possible that hsMAD1H558 could be an at-risk polymorphism that contributes to attenuated spindle checkpoint function in human cells.

Human mitotic arrest deficiency protein 1, hsMAD1, is a component of the mitotic spindle assembly checkpoint (MSC) that monitors fidelity of chromosomal segregation and guards against emergence of cellular aneuploidy. Because aneuploidy is a pervasive characteristic of human cancers, understanding how MSC genes are regulated is important. Here, we have analyzed human genomic sequences upstream of the 5' most hsMAD1 coding exon and have identified a 1.5-kb fragment with promoter activity. The hsMad1 promoter, consistent with characteristics of housekeeping genes, is highly GC rich and is devoid of a TATA-box. Mutational analyses revealed a core region spanning -73 to -31 as being essential for hsMad1 transcription. Surprisingly, although MSC function, prototypically induced by microtubule inhibitors, is active selectively during mitosis, we found the hsMad1 promoter to be expressed predominantly in G1 and to respond not to microtubule inhibitor but to mitogenic stimulus. In primary, as well as transformed cells, intracellular levels of hsMAD1 correlated with the proliferative status of cells. The hsMad1 promoter was also activated preferentially by a gain-of-function p53 mutant. Taken together, our results suggest that hsMAD1 might link p53 function to the generation of cellular aneuuploidy and that heightened activation of hsMad1 by gain-of-function p53 mutants could contribute to the worse prognosis of certain cancers.

The Tax protein of human T-lymphotropic virus type 1 (HTLV-1), an oncoprotein that transactivates viral and cellular genes, plays a key role in HTLV-1 replication and pathogenesis. We used cDNA microarrays to examine Tax-mediated transcriptional changes in the human Jurkat T-cell lines JPX-9 and JPX-M which express Tax and Tax-mutant protein, respectively, under the control of an inducible promoter. Approximately 300 of the over 2000 genes examined were differentially expressed in the presence of Tax. These genes were grouped according to their function and are discussed in the context of existing findings in the literature. There was strong agreement between our results and genes previously reported as being Tax-responsive. Genes that were differentially expressed in the presence of Tax included those related to apoptosis, the cell cycle and DNA repair, signaling factors, immune modulators, cytokines and growth factors, and adhesion molecules. Functionally, we provide evidence that one of these genes, the mixed-lineage kinase MLK-3, is involved in Tax-mediated NF-kappa-B signaling. Our current results provide additional insights into Tax-mediated signaling.

Tax protein expressed by human T cell leukemia virus type 1 (HTLV-1) is a strong trans-activator of its own LTR promoter; it also affects the function of multiple cellular genes involved in cell cycle control and transcription. One way in which Tax exerts its pleiotropic effects is through protein-protein interaction with cellular cofactors. By using yeast two-hybrid technology, we have isolated several cellular proteins that bind to Tax. Two of these are MAD1, a mitotic checkpoint control protein, and TXBP151, a suppressor of tumor necrosis factor alpha-induced apoptosis. Here we discuss findings describing the role of MAD1 in exit of cells from mitosis and TXBP151 in NF-kappaB activation.

The hot-water flash power generating plant recently developed by Mitsubishi Heavy Industries for diesel ship application far exceeds the conventional economizer-steam power generating plant in terms of waste heat recovery rate, and hence can adequately do its job even with the limited waste heat energy available from the lean exhaust of the increasingly fuel-efficient marine diesel engines which are also smaller for the ship size than hitherto and which are frequently run at part loads for slow steaming. Thus, it is believed that the hot-water flash power generating plant will prove especially worthwhile for ships powered by diesel engines 12, 000 PS and above in output, all these ships now finding it almost practically impossible to employ the conventional economizer-steam power plant.Mitsubishi's hot-water flash power generating plant comes in two types; MARK-N1 and MARK-N2. The former recovers the engine exhaust gas energy all with pressurized water in the exhaust-gas economizer and produces steam by flashing pressurized hot water to drive its generator turbine: The latter, though also equipped with the economizer, recovers high-temperature engine exhaust gas energy as steam and heat of low-temperature exhaust gas and scavenging air with pressurized water to drive the generator turbine with both superheated steam and flash steam.

EBV-encoded small RNAs (EBERs) are non-polyadenylated and abundantly transcribed RNAs, whose functions have not yet been fully elucidated. Here, we report that the EBV-negative B lymphoma cell line, BJAB, was rendered more malignant and resistant to apoptosis by EBERs. EBER-transfected cells exhibited enhanced growth potential in SCID mice as well as in soft agar, and showed resistance to apoptotic stimuli in comparison with the vector control. EBERs inhibited the activity of the double-stranded RNA-dependent protein kinase, PKR, which is reputed to act as a tumor-suppressor. These results suggest that EBERs play an important role in the pathogenesis of EBV-associated malignancies through the inhibition of PKR.