Cluster II che genes of Pseudomonas syringae pv. tabaci 6605, orthologs of cluster I in Pseudomonas aeruginosa, are required for chemotaxis and virulence.

Pseudomonas syringae pv. tabaci 6605 (Pta6605) is a causal agent of wildfire disease in host tobacco plants and is highly motile. Pta6605 has multiple clusters of chemotaxis genes including cheA, a gene encoding a histidine kinase, cheY, a gene encoding a response regulator, mcp, a gene for a methyl-accepting chemotaxis protein, as well as flagellar and pili biogenesis genes. However, only two major chemotaxis gene clusters, cluster I and cluster II, possess cheA and cheY. Deletion mutants of cheA or cheY were constructed to evaluate their possible role in Pta6605 chemotaxis and virulence. Motility tests and a chemotaxis assay to known attractant demonstrated that cheA2 and cheY2 mutants were unable to swarm and to perform chemotaxis, whereas cheA1 and cheY1 mutants retained chemotaxis ability almost equal to that of the wild-type (WT) strain. Although WT and cheY1 mutants of Pta6605 caused severe disease symptoms on host tobacco leaves, the cheA2 and cheY2 mutants did not, and symptom development with cheA1 depended on the inoculation method. These results indicate that chemotaxis genes located in cluster II are required for optimal chemotaxis and host plant infection by Pta6605 and that cluster I may partially contribute to these phenotypes.

A Renal Variant of Fabry Disease Diagnosed by the Presence of Urinary Mulberry Cells.

Fabry disease is a lysosomal storage disorder caused by a deficiency of α-galactosidase A. This disease is classified into two types, namely a classical and variant type. We herein present the case of a 36-year-old man who showed a renal variant of Fabry disease and was diagnosed at an early stage by the presence of mulberry cells. He had no history of general symptoms except for proteinuria. The presence of mulberry cells caused us to suspect Fabry disease and he was thereafter diagnosed to have a renal variant of Fabry disease based on the findings of a renal biopsy, a mutation analysis and a low level of α-galactosidase A activity.

Hyperthyroidism associated with obesity-related glomerulopathy-like pathologic features.

Thyroid dysfunction is related to many kidney diseases. We herein present the case of a 39-year-old woman who exhibited obesity-related glomerulopathy-like pathologic features in combination with hyperthyroidism. She displayed hyperthyroidism in spite of receiving anti-thyroid drug treatment, with massive proteinuria (4.5 g/gCr). A renal biopsy demonstrated glomerular hypertrophy (average diameter, 280 µm) and an increased number of capillary vessels, both of which are compatible with a diagnosis of obesity-related glomerulopathy. Following thyroidectomy, the proteinuria gradually decreased in association with an improvement in hyperphagia and normalization of the thyroid function. Obesity-related nephropathy associated with hyperthyroidism is very rare. In this report, we discuss the relationship between hyperthyroidism and obesity-related glomerulopathy-like pathologic features.

Human parvovirus B19-induced acute glomerulonephritis: a case report.

Human parvovirus B19 (HPV B19) infection is well known as a cause of erythema infectiosum in children. Acute glomerulonephritis due to HPVB19 infection is rarely observed in adults. Here, we present the case of a 45-year-old female who showed acute glomerulonephritis induced by HPVB19 infection with various autoantibodies. She had proteinuria (175 mg/g creatinine) and hematuria (20-29 erythrocytes per high-power field) in a urinalysis, and various autoantibodies such as antinuclear antibodies, proteinase-3-antineutrophil cytoplasmic antibodies (PR3-ANCA), antiglomerular basement membrane (GBM) antibodies, and anticardiolipin antibodies in a blood examination. A renal biopsy showed that endocapillary proliferative glomerulonephritis comprised of mononuclear cell infiltration. By using immunofluorescence microscopy, IgG, IgA, IgM, C3, C4, and C1q deposits were detected mainly in glomerular capillaries. Electron-dense deposits were detected in the subendothelial area and mesangial area by using electron microscopy. All symptoms and abnormal laboratory data were self-improved. Our patient's case may provide a clue to the etiology of ANCA-associated vasculitis or lupus nephritis.

A case of focal segmental glomerulosclerosis with myeloid bodies.

The presence of myeloid bodies in electron microscopy is a characteristic finding of Fabry's disease. Here, we present a male patient, whose renal biopsy findings suggested the coexistence of focal segmental glomerulosclerosis and Fabry's disease, because of the presence of segmental hyalinosis and/or sclerosis in glomeruli and myeloid bodies in electron microscopy. But finally, Fabry's disease was excluded as a diagnosis because the α-galactosidase A activity in leukocyte and plasma in this patient was within normal limits. After renal biopsy, although he received medication including steroid therapy, his renal function gradually decreased to end-stage renal failure and hemodialysis was initiated. Until now, he does not exhibit any specific symptoms. In conclusion, our case suggests that occasional myeloid bodies in renal biopsy specimens should be interpreted with caution.

Serum TNF-related and weak inducer of apoptosis levels in septic shock patients.

Capillary permeability is a tightly regulated feature of microcirculation in all organ beds. In sepsis, this feature is fundamentally altered. We have previously reported elevated levels of angiopoietin-2 in patients with septic shock, and have investigated tumor necrosis factor (TNF)-related and weak inducer of apoptosis (TWEAK), which mediates both angiogenesis and inflammation, in those patients. Enzyme-linked immunoassay was used to measure serum TWEAK levels in 20 patients with septic shock, all of whom were treated by direct hemoperfusion with a polymyxin B-immobilized fiber column (DHP-PMX), and in 20 non-septic controls. The TWEAK levels were higher in patients with septic shock (192.8 ± 230.5 pg/mL) than in controls (84.1 ± 28.7 pg/mL, P = 0.043). Between 11 survivors and 10 non-survivors, there was no significant difference in the serum TWEAK levels before the DHP-PMX therapy. During DHP-PMX therapy, however, the serum TWEAK levels were significantly increased in non-survivors (142.2 ± 88.1 pg/mL to 399.0 ± 307.1 pg/mL, P = 0.022). There was a significant correlation between the serum TWEAK levels and white blood cell counts (r = 0.393, P < 0.001), platelet counts (r = 0.418, P < 0.001), or serum CRP levels (r = 0.259, P = 0.029), but there was no correlation between the serum TWEAK levels and blood pressure. The serum TWEAK levels were also correlated with the ratio of angiopoietin-2 to -1 (r = 0.464, P < 0.001). TWEAK may be a suitable marker of disease severity and mortality in septic patients, and TWEAK levels may be associated with vascular permeability via angiopoietin balance.

Analysis of T-cell receptor usage in myeloperoxidase--antineutrophil cytoplasmic antibody-associated renal vasculitis.

BACKGROUND: Bacterial superantigens produced by Staphylococcus aureus may be associated with the onset of proteinase-3 antineutrophil cytoplasmic antibody (PR3-ANCA)-associated vasculitis, including Wegener's granulomatosis. We investigated T-cell subsets to assess the superantigens present in patients with myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA)-associated vasculitis. METHODS: Peripheral-blood mononuclear cells (PBMC) obtained from 40 normal controls and ten patients with MPO-ANCA-associated vasculitis were stained with fluorescence-labeled monoclonal antibodies against T-cell markers, including 17 variable regions of T-cell receptor beta-chains (TCR-Vbeta) and were then analyzed using flow cytometry. RESULTS: Among PBMCs, the percentage of CD3(+) cells from patients with MPO-ANCA-associated vasculitis was significantly lower than that from normal controls, but there were no differences between the two groups in the percentage of CD19(+) cells or CD16(+) cells. Although there were no differences regarding the overall percentage of CD4(+) cells between the two groups, the percentage of CD4(+)CD45RO(+) cells in patients with MPO-ANCA-associated vasculitis was significantly higher than that in normal controls, and percentages of CD4(+)CD45RO(+)HLA-DR(+) and CD4(+)CD45RO(+)CD62L(low) cells in patients with MPO-ANCA-associated vasculitis were also significantly increased. There was no significant difference between the two groups in terms of the usage of the 17 different TCR-Vbeta regions. CONCLUSION: There was no difference in bacterial superantigens between controls and MPO-ANCA-associated vasculitis patients because of the absence of specific usage of TCR-Vbeta regions. Given the elevated levels of memory T cells, conventional antigens rather than superantigens may be associated with the pathogenesis of MPO-ANCA-associated vasculitis.

Angiopoietin balance in septic shock patients treated by direct hemoperfusion with polymyxin b-immobilized fiber.

Capillary permeability is a tightly regulated feature of microcirculation in all organ beds; however, in sepsis this feature is fundamentally altered. We previously reported elevated levels of vascular endothelial growth factor and its receptor (fms-like tyrosine kinase-1) in patients with septic shock, then investigated two kinds of angiopoietins in those patients. An enzyme-linked immunoassay was used to measure serum angiopoietin-1 and -2 levels in 12 patients with septic shock who were treated by direct hemoperfusion with a polymyxin B-immobilized fiber column (DHP-PMX). The angiopoietin-1 level was lower in patients with septic shock (7.01 +/- 10.08 ng/mL) than in controls (28.24 +/- 11.61 ng/mL, P < 0.001), but the angiopoietin-2 level was higher in septic shock patients (40.83 +/- 30.13 ng/mL vs. 2.47 +/- 1.78 ng/mL, P < 0.001). Between seven survivors and five non-survivors there was no significant difference in angiopoietin-1 levels before DHP-PMX therapy. During DHP-PMX therapy, however, the angiopoietin-2 level was significantly decreased in survivors (31.52 +/- 26.15 ng/mL vs. 17.32 +/- 22.46 ng/mL, P = 0.035). Moreover, at the end of the therapy, the angiopoietin-1 level was significantly lower in non-survivors (1.14 +/- 1.30 ng/mL vs. 10.43 +/- 13.56 ng/mL, P = 0.042), but the angiopoietin-2 level in non-survivors was significantly higher (70.79 +/- 40.47 ng/mL vs. 17.32 +/- 22.46 ng/mL, P = 0.019). The angiopoietin-2 level may be associated with vascular permeability in septic patients, and angiopoietins may be suitable markers of disease severity and mortality.

Discovery of dense aggregations of stalked crinoids in Izu-Ogasawara trench, Japan.

Stalked crinoids are recognized as living fossils that typically inhabit modern deep-water environments exceeding 100 m. Previous records of stalked crinoids from hadal depths (exceeding 6000 m) are extremely rare, and no in-situ information has been available. We show here that stalked crinoids live densely on rocky substrates at depths over 9000 m in the Izu-Ogasawara Trench off the eastern coast of Japan, evidenced by underwater photos and videos taken by a remotely operated vehicle. This is the deepest in-situ observation of stalked crinoids and demonstrates that crinoid meadows can exist at hadal depths close to the deepest ocean floor, in a fashion quite similar to populations observed in shallower depths.

Vascular endothelial growth factor and soluble fms-like tyrosine kinase-1 in septic shock patients treated with direct hemoperfusion with a polymyxin B-immobilized fiber column.

Sepsis is characterized by a systemic inflammatory response to a microbial pathogen. In sepsis, capillary permeability is a tightly regulated feature of microcirculation in all organ beds and is fundamentally altered. We investigated the vascular endothelial growth factor (VEGF) level as a vascular permeability factor and the soluble fms-like tyrosine kinase-1 (Flt-1) level as an antagonist of the VEGF receptors. Serum VEGF and soluble Flt-1 levels in 21 patients with septic shock, who were treated with direct hemoperfusion with a polymyxin B-immobilized fiber column (DHP-PMX), were measured by enzyme-linked immunoassay. The VEGF and the soluble Flt-1 levels were more elevated in patients with septic shock than in controls. Between 14 survivors and 7 non-survivors, there was no significant difference in VEGF level before the DHP-PMX therapy, but the soluble Flt-1 level of survivors was significantly lower than that of non-survivors. Although there was no significant difference between starting and ending VEGF levels in survivors, in non-survivors the VEGF level at the end of DHP-PMX therapy was significantly lower than that at the start. In survivors, the soluble Flt-1 level at the end of DHP-PMX therapy was significantly lower than that at the start. On the other hand, in non-survivors, there was no significant difference between the ending and starting soluble Flt-1 levels. The soluble Flt-1 level may be a suitable marker of disease severity and mortality.

Gac two-component system in Pseudomonas syringae pv. tabaci is required for virulence but not for hypersensitive reaction.

Pseudomonas syringae pv. tabaci 6605 causes wildfire disease on host tobacco plants. To investigate the regulatory mechanism of the expression of virulence, Gac two-component system-defective mutants, DeltagacA and DeltagacS, and a double mutant, DeltagacADeltagacS, were generated. These mutants produced smaller amounts of N-acyl homoserine lactones required for quorum sensing, had lost swarming motility, and had reduced expression of virulence-related hrp genes and the algT gene required for exopolysaccharide production. The ability of the mutants to cause disease symptoms in their host tobacco plant was remarkably reduced, while they retained the ability to induce hypersensitive reaction (HR) in the nonhost plants. These results indicated that the Gac two-component system of P. syringae pv. tabaci 6605 is indispensable for virulence on the host plant, but not for HR induction in the nonhost plants.

Effects of glycosylation on swimming ability and flagellar polymorphic transformation in Pseudomonas syringae pv. tabaci 6605.

The role of flagellin glycosylation on motility was investigated in Pseudomonas syringae pv. tabaci. The swimming activity of glycosylation-defective mutants was prominently decreased in a highly viscous medium. The mutants showed differences in polymorphic transitions and in the bundle formation of flagella, indicating that glycosylation stabilizes the filament structure and lubricates the rotation of the bundle.

A homologue of the 3-oxoacyl-(acyl carrier protein) synthase III gene located in the glycosylation island of Pseudomonas syringae pv. tabaci regulates virulence factors via N-acyl homoserine lactone and fatty acid synthesis.

Pseudomonas syringae pv. tabaci 6605 possesses a genetic region involved in flagellin glycosylation. This region is composed of three open reading frames: orf1, orf2, and orf3. Our previous study revealed that orf1 and orf2 encode glycosyltransferases; on the other hand, orf3 has no role in posttranslational modification of flagellin. Although the function of Orf3 remained unclear, an orf3 deletion mutant (Deltaorf3 mutant) had reduced virulence on tobacco plants. Orf3 shows significant homology to a 3-oxoacyl-(acyl carrier protein) synthase III in the fatty acid elongation cycle. The Deltaorf3 mutant had a significantly reduced ability to form acyl homoserine lactones (AHLs), which are quorum-sensing molecules, suggesting that Orf3 is required for AHL synthesis. In comparison with the wild-type strain, swarming motility, biosurfactant production, and tolerance to H2O2 and antibiotics were enhanced in the Deltaorf3 mutant. A scanning electron micrograph of inoculated bacteria on the tobacco leaf surface revealed that there is little extracellular polymeric substance matrix surrounding the cells in the Deltaorf3 mutant. The phenotypes of the Deltaorf3 mutant and an AHL synthesis (DeltapsyI) mutant were similar, although the mutant-specific characteristics were more extreme in the Deltaorf3 mutant. The swarming motility of the Deltaorf3 mutant was greater than that of the DeltapsyI mutant. This was attributed to the synergistic effects of the overproduction of biosurfactants and/or alternative fatty acid metabolism in the Deltaorf3 mutant. Furthermore, the amounts of iron and biosurfactant seem to be involved in biofilm development under quorum-sensing regulation in P. syringae pv. tabaci 6605.

Volcanism in response to plate flexure.

Volcanism on Earth is known to occur in three tectonic settings: divergent plate boundaries (such as mid-ocean ridges), convergent plate boundaries (such as island arcs), and hot spots. We report volcanism on the 135 million-year-old Pacific Plate not belonging to any of these categories. Small alkalic volcanoes form from small percent melts and originate in the asthenosphere, as implied by their trace element geochemistry and noble gas isotopic compositions. We propose that these small volcanoes erupt along lithospheric fractures in response to plate flexure during subduction. Minor extents of asthenospheric melting and the volcanoes' tectonic alignment and age progression in the direction opposite to that of plate motion provide evidence for the presence of a small percent melt in the asthenosphere.