Nerve growth factor regulation and production by macrophages in osteoarthritic synovium.

Nerve growth factor (NGF) functions to modulate osteoarthritis (OA)-associated pain. Although recent studies suggest that tumour necrosis factor (TNF)-α and interleukin (IL)-1ß mediate NGF activity in human synovial fibroblasts, the regulation of NGF expression in human synovial macrophages remains unclear. Here, we examined the role of macrophages in the production and regulation of synovial (SYN) NGF in osteoarthritic knee joints by examining the mRNA expression of TNF-α and IL-1ß in freshly isolated CD14-positive (macrophage-rich fraction) and CD14-negative cells (fibroblast-rich fraction) in synovial tissue from OA patients by quantitative polymerase chain reaction. We also examined the effects of IL-1ß and TNF-α on NGF mRNA expression in cultured CD14-positive (macrophage-rich fraction) and CD14-negative cells (fibroblast-rich fraction). In addition, to examine the contribution of macrophages to NGF, TNF-α and IL-1ß expression, we injected clodronate liposomes systemically into STR/Ort mice, an osteoarthritis animal model, to deplete macrophages. TNF-α and IL-1ß mRNA levels in CD14-positive cells from the SYN of OA patients was significantly higher than that in CD14-negative cells, while NGF expression did not differ markedly between the two cell fractions. In addition, treatment of human cultured CD14-positive and -negative cells with IL-1ß and TNF-α enhanced NGF mRNA and protein levels. Expression of NGF, IL-1ß and TNF-α was also reduced significantly in STR/Ort mice upon macrophage depletion. These findings suggest that IL-1ß and TNF-α regulate NGF expression and production in synovial macrophages and fibroblasts in osteoarthritic joints.

Synovial macrophage-derived IL-1ß regulates the calcitonin receptor in osteoarthritic mice.

Recent studies have reported that calcitonin gene-related peptide (CGRP) contributes to joint pain. However, regulation of the CGRP/CGRP receptor signalling in osteoarthritis (OA) is not fully understood. To investigate the regulation of CGRP/CGRP receptor signalling by macrophages in the synovial tissue (ST) of OA joints, we characterized the gene expression profiles of CGRP and CGRP receptors in the ST of OA mice (STR/Ort). In addition, we examined whether macrophage depletion by the systemic injection of clodronate-laden liposomes affected the expression of CGRP and CGRP receptors in ST. CD11c(+) macrophages in the ST of STR/Ort and C57BL/6J mice were analysed by flow cytometry. Real-time polymerase chain reaction (PCR) was used to evaluate the expression of interleukin (IL)-1ß, CGRP, calcitonin receptor-like receptor (CLR) and receptor activity-modifying protein 1 (RAMP1) in F4/80(+) and F4/80(-) cells. The effects of IL-1ß on the expression of CGRP and CLR by cultured synovial cells were also examined. The percentage of CD11c(+) macrophages in the ST of STR/Ort was higher than that in C57/BL6J mice. Notably, the F4/80(+) cell fraction expressed IL-1ß highly, whereas the F4/80(-) cell fraction expressed CGRP, CLR, and RAMP1 highly. In addition, expression of the IL-1ß and CLR genes was increased in ST, but was decreased upon macrophage depletion, and the IL-1ß treatment of cultured synovial cells up-regulated CLR. Taken together, the present findings suggest that synovial macrophages are the major producers of IL-1ß and regulators of CLR in OA mice. Therefore, macrophages and IL-1ß may be suitable therapeutic targets for treating OA pain.

CD11c(+) macrophages and levels of TNF-α and MMP-3 are increased in synovial and adipose tissues of osteoarthritic mice with hyperlipidaemia.

To understand more clearly the link between osteoarthritis and hyperlipidaemia, we investigated the inflammatory macrophage subsets and macrophage-regulated matrix metalloprotease-3 (MMP-3) and A disintegrin and metalloprotease with thrombospondin motifs-4 (ADAMTS4) in synovial (ST) and adipose tissues (AT) of osteoarthritic mice with hyperlipidaemia (STR/Ort). CD11c(+) F4/80(+) CD11b(+) macrophage populations in the ST and AT of 9-month-old STR/Ort and C57BL/6J mice were characterized and compared by flow cytometry and real-time polymerase chain reaction (PCR) analyses. Expression of tumour necrosis factor (TNF)-α, MMP-3 and ADAMTS4, and the response of these factors to anionic liposomal clodronate induced-macrophage depletion were also evaluated by real-time PCR. Expression of TNF-α in CD11c(+) cells, which were isolated by magnetic beads, was compared to CD11c(-) cells. In addition, the effect of TNF-α on cultured synovial fibroblasts and adipocytes was investigated. CD11c(+) F4/80(+) CD11b(+) macrophages were increased in ST and AT of STR/Ort mice. The CD11c(+) cell fraction highly expressed TNF-α. Expression of TNF-α and MMP3 was increased in ST and AT, and was decreased upon macrophage depletion. TNF-α treatment of cultured synovial fibroblasts and adipocytes markedly up-regulated MMP-3. CD11c(+) F4/80(+) CD11b(+) macrophages were identified as a common inflammatory subset in the AT and ST of STR/Ort mice with hyperlipidaemia. The induction of inflammation in AT and ST may be part of a common mechanism that regulates MMP3 expression through TNF-α. Our findings suggest that increased numbers of CD11c(+) macrophages and elevated levels of TNF-α and MMP-3 in AT and ST may explain the relationship between hyperlipidaemia and OA.

Sevoflurane suppresses tumour necrosis factor-α-induced inflammatory responses in small airway epithelial cells after anoxia/reoxygenation.

BACKGROUND: Lung ischaemia-reperfusion (I/R) injury is correlated with poor clinical outcome. The inflammatory cytokines interleukin (IL)-6, IL-8, and monocyte chemotactic protein-1 (MCP-1) are produced by pulmonary epithelial cells during lung transplantation and are considered to be involved in I/R injury. The volatile anaesthetic sevoflurane has been shown to exert a protective effect on I/R injury in various organs. We investigated the effect of sevoflurane on the inflammatory functions of pulmonary epithelial cells in vitro. METHODS: Human normal small airway epithelial cells (SAEC) were incubated under anoxic conditions for 24 h with or without sevoflurane and then stimulated with tumour necrosis factor (TNF)-α under hyperoxic conditions for 5 h with or without sevoflurane. After incubation, IL-6, IL-8, and MCP-1 mRNA expression was analysed by quantitative real-time RT-PCR. The production of IL-6, IL-8, and MCP-1 was assayed by enzyme-linked immunosorbent assay, the effects of sevoflurane on inflammatory gene expression were examined by DNA microarray analysis, and the effects of sevoflurane on NF-κB-mediated inflammatory cytokine production were examined by immunoblotting. RESULTS: Sevoflurane suppressed TNF-α-induced IL-6, IL-8, and MCP-1 gene expression and the production of IL-6 and IL-8 in SAEC under anoxia/reoxygenation conditions. DNA microarray analysis indicated that sevoflurane modulated NF-κB-related gene expression. Sevoflurane significantly inhibited TNF-α-induced translocation of p65 NF-κB into the nucleus. Sevoflurane enhanced TNF-α-induced gene expression of inhibitor κB (IκB) but not of NF-κB. CONCLUSIONS: Sevoflurane suppressed the NF-κB-mediated production of pulmonary epithelial cell-derived inflammatory cytokines, including IL-6 and IL-8, which are capable of causing I/R injury.

Glycosphingolipids regulate ameloblastin expression in dental epithelial cells.

Neurotrophin 4 (NT-4) and its receptors regulate the differentiation of ameloblasts in tooth development. Gangliosides, sialic acids that contain glycosphingolipids (GSLs), are involved in a variety of membrane-associated cell physiological functions such as ligand-receptor signal transmission. However, the expression patterns and functions of GSLs during tooth development remain unclear. In this study, we identified strong expressions of GM3 and LacCer in dental epithelium, which give rise to differentiation into enamel-secreting ameloblasts. Exogenous GM3 and LacCer in dental epithelial cells induced the expression of ameloblastin (Ambn), while it was also interesting that GM3 synergistically exerted enhancement of NT-4-mediated Ambn expression. In addition, consistently exogenous GM3 and LacCer in dental epithelial cells induced distinct activation of extracellular signal-regulated kinase 1/2 (ERK1/2), an event upstream of the expression of Ambn. Furthermore, depletion of GSLs from dental epithelial cells by D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (D-PDMP) inhibited Ambn expression as well as phosphorylation of ERK1/2. In contrast, exogenous addition of GM3 or LacCer rescued the phosphorylation of ERK1/2 repressed by pre-treatment with D-PDMP. Taken together, these results suggest that GM3 and LacCer are essential for NT-4-mediated Ambn expression, and contribute to dental epithelial cell differentiation into ameloblasts.

Role of stromal microenvironment in nonpharmacological resistance of CML to imatinib through Lyn/CXCR4 interactions in lipid rafts.

We and others have previously demonstrated that p210 Bcr-Abl tyrosine kinase inhibits stromal cell-derived factor-1α/CXCR4 chemokine receptor signaling, contributing to the deficient adhesion of chronic myeloid leukemia (CML) cells to bone marrow stroma. Conversely, exposure of CML cells to a tyrosine kinase inhibitor (TKI) enhances migration of CML cells towards stromal cell layers and promotes non-pharmacological resistance to imatinib. Src-related kinase Lyn is known to interact with CXCL12/CXCR4 signaling and is directly activated by p210 Bcr-Abl. In this study, we demonstrate that TKI treatment promoted CXCR4 redistribution into the lipid raft fraction, in which it co-localized with active phosphorylated form of Lyn (LynTyr396) in CML cells. Lyn inhibition or cholesterol depletion abrogated imatinib-induced migration, and dual Src/Abl kinase inhibitor dasatinib induced fewer CML cells to migrate to the stroma. These findings demonstrate the novel mechanism of microenvironment-mediated resistance through lipid raft modulation, which involves compartmental changes of the multivalent CXCR4 and Lyn complex. We propose that pharmacological targeting of lipid rafts may eliminate bone marrow-resident CML cells through interference with microenvironment-mediated resistance.

Protein biomarker analysis by mass spectrometry in patients with rheumatoid arthritis receiving anti-tumor necrosis factor-alpha antibody therapy.

OBJECTIVE: To investigate the mechanism of action of anti-tumor necrosis factor-alpha (TNF-alpha) antibody in patients with rheumatoid arthritis (RA), we analyzed serum or plasma proteins by mass spectrometry system. METHODS: Ten RA patients who received treatment with anti-TNF-alpha antibody were studied. Samples obtained before and after therapy were analyzed by a two-dimensional liquid chromatography tandem mass spectrometry (2D LC-MS/MS) system after pretreatment by a recently developed method to remove high molecular weight proteins. RESULTS: Using this system, certain proteins were identified after treatment with anti-TNF-alpha antibody, including proteins related to the TNF-alpha-mediated pathway for nuclear factor kappa B (NF-kappaB) activation and/or to the metabolism (including regeneration) of articular cartilage. CONCLUSION: Our mass spectrometry system appears to be useful for proteomic analysis. The efficacy of anti-TNF-alpha antibody therapy for RA may be related to various consequence of the inhibition of TNF-alpha activity.

Expansion of CD4+CD28- T cells producing high levels of interferon-{gamma} in peripheral blood of patients with multiple sclerosis.

CD4(+) T cells that lack surface expression of the CD28 co-stimulatory molecule (CD4(+)CD28(-) T cells) were expanded in peripheral blood of patients with multiple sclerosis (MS) [5.20 +/- 1.67% vs 13.00 +/- 2.68% (healthy controls (HC) versus patients with MS)]. Both the CD4(+)CD28(+) and CD4(+)CD28(-) T-cell populations of patients with MS produced higher levels of interferon (IFN)-gamma compared with those in HC. In particular, the proportion of IFN-gamma(+) cells among CD4(+)CD28(-) T cells from patients with MS was considerably high. However, expression of co-stimulatory molecules including inducible costimulator (ICOS), activating natural killer receptors, or members of tumor necrosis factor receptor family that replace CD28 in CD4(+)CD28(-) T cells of patients with MS could not be identified. A unique subpopulation bearing the CD45RA(high)CCR7(-) phenotype was identified among the CD4(+)CD28(-) T cells of some patients with MS. Because only MS samples contained this CD45RA(high)CCR7(-) population attributed to terminally differentiated effector memory cells and lacked naive CD45RA(high)CCR7(+) cells, we suggest that CD4(+)CD28(-) T cells of patients with MS represent a cell population which is in more differentiated state than healthy subjects. In patients treated with IFN-beta-1b, IFN-gamma production from CD4(+)CD28(+) T cells was suppressed compared with that in untreated patients. On the contrary, in the CD4(+)CD28(-) population, production of IFN-gamma in IFN-beta-1b-treated patients was not significantly suppressed compared with that in untreated patients with MS. Thus, an additional treatment strategy that specifically targets this cell population may enhance the beneficial effect of IFN-beta on MS.

Effect of high fat diet on NKT cell function and NKT cell-mediated regulation of Th1 responses.

Diet is one of the important factors that modulate immune responses. In the present study, we have examined the capacity of dietary lipids to modify immune responses in mice and we have investigated the contribution of glycolipid-reactive natural killer T (NKT) cells in this process. Mice fed, high fat diet (HFD; 21.2% fat, 0.20% cholesterol) for 3 weeks, as compared with mice fed standard fat diet (SFD; 4.3% fat, 0.03% cholesterol), showed significantly reduced interferon-gamma production in sera at 6 or 12 h after intraperitoneal injection of an NKT cell ligand, alpha-galactosylceramide. In contrast, production of interleukin-13 was significantly higher at 2 and 6 h in HFD fed mice compared with mice on SFD. No difference was detected in the serum interleukin-4 levels between these two groups of animals. The proportion of NKT cells in spleen and liver was reduced in mice fed HFD compared with those on SFD. In addition, activation of NKT cells assessed by up-regulation of CD69 was suppressed specifically in liver from mice fed HFD. Recall responses of conventional T cells and delayed-type hypersensitivity (Th1 type) against ovalbumin were significantly suppressed in mice fed HFD in comparison with those fed SFD. This suppression was not observed in CD1d-/- mice, suggesting that NKT cells in mice fed HFD played a role in suppressing Th1 responses. Taken together, our findings suggest a critical link between NKT cells, dietary lipid and adaptive immune responses.

Allergic inflammatory reaction is involved in necrosis of human pulmonary dirofilariasis.

AIMS: To determine whether, in view of the massive inflammatory cell infiltration and the rounded rather than wedge-shaped character of pulmonary lesions in dirofilariasis, the inflammatory response against the worm contributes to the coagulative necrosis, in addition to an ischaemic process. METHODS AND RESULTS: The histopathological features of 13 resected dirofilariasis cases with well-defined nodules ranged from 10 to 30 mm were analysed. On routine histology and using immunohistochemistry, the peripheral encapsulating wall showed mild to severe infiltration of eosinophils, lymphocytes and plasma cells and a histiocytic reaction in all cases, often with necrotic eosinophils seen within the necrosis (84.6%) and inflammatory changes in the adjacent lung (38.5%). The CD4+ lymphocyte count (80.8 +/- 33.4) was greater than that of CD8+ lymphocytes (24.5 +/- 16.9) in the central necrosis and vice versa in the wall. In the necrotic regions, disruption of the pulmonary artery (61.5%) and extravasation of the torn worm (23.1%) could be seen. CONCLUSIONS: These findings indicate that an allergic inflammatory reaction, mediated by eosinophils and lymphocytes, is involved in the formation of the dirofilarial necrotizing granuloma rather than infarction caused simply by embolism.

Decrease in the glyceraldehyde derived advanced glycation end products in the sera of patients with Vogt-Koyanagi-Harada disease.

BACKGROUND/AIMS: Advanced glycation end products (AGEs) are considered to act as mediators of both age related pathologies and diabetic complications. It was recently reported that glyceraldehyde derived AGE (AGE-2) has a strong biological effect on various diseases. The aim of this study was to investigate the serum AGE-2 levels in Vogt-Koyanagi-Harada (VKH) disease. METHODS: Sera were obtained from 31 patients with active VKH. 20 of these 31 patients were treated with systemic corticosteroids. As controls, 33 healthy volunteers were also examined. The serum AGE-2 levels were determined with a competitive enzyme linked immunosorbent assay using AGE-2 polyclonal antibody. RESULTS: The mean AGE-2 level in the sera of patients with VKH disease was 4.91 (SD 2.23) U/ml, which was significantly lower than that of the healthy control subjects (8.32 (2.94), p<0.001). The average serum AGE-2 level significantly increased to 13.49 (2.17) U/ml after the patients were treated with systemic corticosteroids (p<0.001). CONCLUSIONS: These results suggest that AGE-2 may be involved in the onset of VKH disease.

Immunoregulatory defects of V alpha 24V+ beta 11+ NKT cells in development of Wegener's granulomatosis and relapsing polychondritis.

The frequency of either CD4(-)8(-) (double negative; DN) or CD4(+) V alpha 24(+)V beta 11(+) NKT cells, the expression of CD1d and the binding of CD1d-tetramer loaded with alpha-galactosylceramide (alpha-GalCer) to NKT cells were analysed in peripheral blood mononuclear cells (PBMCs) of patients with Wegener's granulomatosis (WG), relapsing polychondritis (RP) and healthy subjects (HS). DN and CD4(+) V alpha 24(+)V beta 11(+) NKT cells as well as CD1d-alpha-GalCer tetramer-positive NKT cells, were significantly decreased in number in both WG and RP patients compared to those from HS. When cytokine profiles were analysed in these PBMCs upon stimulation with phorbol ester and calcium ionophore, CD4(+) T cells from patients with WG and RP exhibited a Th1 bias, whereas CD4(+) NKT cells from WG patients in remission showed a Th2 bias. These findings suggest that NKT cells (especially CD4(+) NKT cells) play a regulatory role in Th1 autoimmunity in patients with WG and RP. The reduction in NKT cell counts appears to be associated with the low responsiveness to alpha-GalCer. The dysfunction of NKT cells to recognize ligands such as alpha-GalCer may also contribute to the defects observed in NKT cells from WG and RP patients.

Glucosamine, a naturally occurring amino monosaccharide, suppresses the ADP-mediated platelet activation in humans.

OBJECTIVE: To evaluate the anti-thrombotic action of glucosamine, a naturally occurring amino monosaccharide, platelets were stimulated with ADP in the presence of glucosamine, and its effects on platelet functions were examined. MATERIALS AND METHODS: Human platelet-rich plasma was stimulated with 2.5 microM ADP in the presence of glucosamine (0.01 approximately 1 mM) or other aminosugars (N-acetyl-glucosamine, galactosamine or N-acetyl-galactosamine, 1 mM), and platelet aggregation was monitored. Furthermore, the effects of glucosamine on the thromboxane A2 production, release of granule contents, intracellular calcium mobilization and phosphorylation of Syk (a 72 kD protein tyrosine kinase) were evaluated following ADP-stimulation. In addition, the binding of [3H] ADP to its receptors was examined. RESULTS: Glucosamine (>0.01 mM) dose-dependently suppressed platelet aggregation in response to ADP (p < 0.05), whereas N-acetyl-glucosamine, galactosamine or N-acetyl-galactosamine (1 mM) did not affect the ADP-induced platelet aggregation. Furthermore, glucosamine (>0.1 mM) inhibited the extracellular release of granule contents (ATP and platelet factor 4) and production of thromboxane A2 from ADP-stimulated platelets (p < 0.05). Moreover, glucosamine significantly repressed the intracellular calcium mobilization at >0.1 mM and phosphorylation of Syk at >0.01 mM upon ADP-stimulation (p < 0.05). In addition, glucosamine (>0.1 mM) inhibited the binding of ADP to its receptors (p < 0.05). CONCLUSION: Glucosamine is able to suppress platelet aggregation, release of granule constituents, thromboxane A2 production, calcium mobilization and phosphorylation of Syk possibly via the inhibition of ADP-binding to the receptors. Glucosamine could be expected as a novel anti-platelet agent for thrombotic disorders due to its suppressive actions on platelets.

Centrosome hyperamplification and chromosomal damage after exposure to radiation.

OBJECTIVE: In order to elucidate the effects of radiation on centrosome hyperamplification (CH), we examined the centrosome duplication cycle in KK47 bladder cancer cells following irradiation. METHODS: KK47 cells were irradiated with various doses of radiation and were examined for CH immunostaining for gamma-tubulin. RESULTS: Nearly all control cells contained one or two centrosomes, and mitotic cells displayed typical bipolar spindles. The centrosome replication cycle is well regulated in KK47. Twenty-four hours after 5-Gy irradiation, approximately 80% of irradiated cells were arrested in G2 phase, and at 48 h after irradiation, 56.9% of cells contained more than two centrosomes. Laser scanning cytometry performed 48 h after irradiation showed the following two pathways: (1) unequal distribution of chromosomes to daughter cells, or (2) failure to undergo cytokinesis, resulting in polyploidy. With mitotic collection, M-phase cells with CH could be divided into G1 cells with micronuclei and polyploidal cells. Fluorescence in situ hybridization analysis showed clear signs of chromosomal instability (CIN) at 48 h after irradiation. The present study had two major findings: (1) continual duplication of centrosomes occurred in the cell cycle-arrested cells upon irradiation, leading to centrosome amplification; (2) cytokinesis failure was due to aberrant mitotic spindle formation caused by the presence of amplified centrosomes. Abnormal mitosis with amplified centrosomes was detected in the accumulating G2/M population after irradiation, showing that this amplification of centrosomes was not caused by failure to undergo cytokinesis, but rather that abnormal mitosis resulting from amplification of centrosomes leads to cytokinesis block. CONCLUSION: These results suggest that CH is a critical event leading to CIN following exposure to radiation.

VEGF regulates the proliferation of acid-exposed alveolar lining epithelial cells.

BACKGROUND: Acid induced pneumonitis resulting in acute respiratory distress syndrome (ARDS) is characterised by increased alveolar permeability and accumulation of neutrophils. It is hypothesised that vascular endothelial growth factor (VEGF) is involved in the development of lung oedema. Furthermore, lower levels of VEGF are detected in bronchoalveolar lavage fluid from patients with ARDS than from non-ARDS patients. We hypothesised that VEGF acts cytoprotectively and have investigated this possibility in vitro with A549 cells. METHODS: A549 cells were incubated in 24 well culture dishes 24 hours before exposure to acid, then incubated with serum free medium containing various concentrations of HCl for 30 minutes at 37 degrees C in 5% CO(2). The acidified medium was changed to normal complete medium; at specified incubation periods the supernatants were collected and the VEGF concentration measured and the number of adherent cells counted. RESULTS: Proliferation of A549 cells and VEGF production were suppressed for at least 48 hours in HCl at a concentration of 50 mM. Restoration of cellular proliferation occurred following exogenous administration of VEGF (concentration of 1-250 ng/ml) and was inhibited by co-incubation with neutralising anti-VEGF antibody, indicating an interaction between VEGF molecules and A549 cells. Control cells were not influenced by administration of exogenous VEGF or anti-VEGF antibody. Treatment with neutralising anti-VEGF receptor (VEGFR) antibodies against VEGFR-1 and VEGFR-2 suppressed proliferation of acid exposed A549 cells but had no effect on control cells. CONCLUSIONS: Exogenous VEGF interacts with VEGFR-1 and VEGFR-2 on the surface and regulates the proliferation of injured alveolar lining epithelial cells in an autocrine or paracrine fashion.

Attenuated nuclear shrinkage in neurones with nuclear inclusions of SCA1 brains.

BACKGROUND: Spinocerebellar ataxia type 1 (SCA1) is one of the autosomal dominant neurodegenerative disorders commonly linked to pathological expansion of the CAG repeat of the relevant gene. Nuclear inclusions and neurodegeneration are both triggered by this pathological expansion of the CAG/polyglutamine repeat on ataxin-1, but it remains to be determined whether or not nuclear inclusion formation is associated with accelerated neurodegeneration. OBJECTIVE: To examine the influence of nuclear inclusions on nuclear size and deformity in human brains from patients suffering from SCA1. MATERIAL: Pontine sections of brains obtained at necropsy from seven patients with SCA1 and five controls. METHODS: The size and deformity of each neuronal nucleus was quantified. Nuclei with and without inclusions were examined separately to assess the possible influence of nuclear inclusions on neurodegeneration. RESULTS: Nuclear shrinkage and deformity were more marked in SCA1 brains than in controls. This shrinkage was attenuated in neurones containing nuclear inclusions. CONCLUSIONS: The existence of nuclear inclusions in SCA1 is presumably linked to a mechanism that attenuates rather than accelerates nuclear shrinkage. This in vivo finding may provide a clue to constructing a rational therapeutic strategy for combating neurodegeneration associated with nuclear inclusions.

Primary gastric T-cell lymphoma not associated with human T-lymphotropic virus type I: a case report and review of the literature.

Primary gastric T-cell lymphoma (PGTL) not associated with human T-lymphotropic virus type I (HTLV-I) is extremely rare and such a case is reported herein. The patient was a 58-year-old Japanese male presenting with submucosal tumor of the stomach identified on endoscopic examination. The lesion was diagnosed as non-Hodgkin's lymphoma by endoscopic biopsy and classified as peripheral T-cell lymphoma, unspecified, due to clonal rearrangement of the T-cell receptor beta (TCR) gene and expression of TCR beta protein in the absence of B-cell genotypes and phenotypes. Unlike previously reported cases of HTLV-I-unassociated PGTL, lymphoma in the current case was characterized histologically as "low grade" and phenotypically as CD4+, TIA-1+, granzyme B+, and CD103-. The lymphoma responded well to chemotherapy and radiation, and the patient was well with no detectable disease 10 months after initiation of therapy. A review of patients with PGTL in the literature revealed a few long-term survivors, and the investigation of therapeutic strategies for PGTL is, therefore, necessary.

Short-term and long-term effects of low total pressure on gas exchange rates of spinach.

In this study, spinach plants were grown under atmospheric and low pressure conditions with constant O2 and CO2 partial pressures, and the effects of low total pressure on gas exchange rates were investigated. CO2 assimilation and transpiration rates of spinach grown under atmospheric pressure increased after short-term exposure to low total pressure due to the enhancement of leaf conductance. However, gas exchange rates of plants grown at 25 kPa total pressure were not greater than those grown at atmospheric pressure. Stomatal pore length and width were significantly smaller in leaves grown at low total pressure. This result suggested that gas exchange rates of plants grown under low total pressure were not stimulated even with the enhancement of gas diffusion because the stomatal size and stomatal aperture decreased.

Paradoxical absence of nuclear inclusion in cerebellar Purkinje cells of hereditary ataxias linked to CAG expansion.

Degeneration of cerebellar cortex is one of the principal features of hereditary ataxias linked to expansion of CAG repeat. In an attempt to clarify possible correlation between neuronal depletion and neuronal intranuclear inclusions, both triggered by the pathological expansion of CAG repeat, cerebellar sections from SCA1, SCA2, SCA3, and DRPLA cases were immunostained with anti-ubiquitin or anti-expanded polyglutamine antibody (1C2) and were screened for the presence of neuronal intranuclear inclusions. Although the degree of cerebellar degeneration varied greatly, cerebellar Purkinje cells were uniformly characterised by the absence of neuronal intranuclear inclusion. Complete absence of neuronal intranuclear inclusion in Purkinje cells is apparently paradoxical and hardly explained if neuronal intranuclear inclusion formation is positively correlated to a mechanism accelerating neuronal death. It may, otherwise, suggest an intrinsic link between neuronal intranuclear inclusion formation and neurodegeneration in opposite directions in human Purkinje cells, more or less affected in these CAG repeat disorders.