Percutaneous Reduction of a Dislocation of the Interphalangeal Joint of the Great Toe: A Case Report.

Dorsal dislocation of the interphalangeal joint of the great toe is quite rare. Closed reduction is often attempted in the emergency setting, but this measure is seldom successful because of invagination of the sesamoid-plantar plate complex into the interphalangeal space. Generally, open reduction is indicated when closed reduction fails. In this report, percutaneous reduction of the incarcerated sesamoid was performed under local and intraarticular anesthesia at our outpatient clinic, leading to successful reduction.

Nutrient salt removal by steel-making slag in sediment microbial fuel cells.

Applying sediment microbial fuel cells (SMFCs) into sediment can remediate the sediment; however, nutrient salts cannot be removed by SMFCs effectively. In this study, sediment mixed with steel-making slag is used a fuel in SMFCs for understanding the potential of steel-making slag in nutrient salt removal in SMFCs. To the best of our knowledge, no report related to the use of steel-making slag in SMFCs is found in the literature. The combination of SMFCs with steel-making slag is expected to make the individual efficiency of SMFCs and steel-making slag more reactive, and is another way to increase the benefit of using steel-making slag. Experimental results showed that steel-making slag was more effective for adsorbing nutrient salts in SMFCs. Interestingly, the combination of SMFCs with steel-making slag can increase the individual efficiency of SMFCs and steel-making slag.

Cross-talk between integrin α6ß4 and insulin-like growth factor-1 receptor (IGF1R) through direct α6ß4 binding to IGF1 and subsequent α6ß4-IGF1-IGF1R ternary complex formation in anchorage-independent conditions.

Integrin αvß3 plays a role in insulin-like growth factor-1 (IGF1) signaling (integrin-IGF1 receptor (IGF1R) cross-talk). The specifics of the cross-talk are, however, unclear. In a current model, "ligand occupancy" of αvß3 (i.e. the binding of extracellular matrix proteins) enhances signaling induced by IGF1 binding to IGF1R. We recently reported that IGF1 directly binds to αvß3 and induces αvß3-IGF1-IGF1R ternary complex formation. Consistently, the integrin binding-defective IGF1 mutant (R36E/R37E) is defective in inducing ternary complex formation and IGF signaling, but it still binds to IGF1R. Like αvß3, integrin α6ß4 is overexpressed in many cancers and is implicated in cancer progression. Here, we discovered that α6ß4 directly bound to IGF1, but not to R36E/R37E. Grafting the ß4 sequence WPNSDP (residues 167-172), which corresponds to the specificity loop of ß3, to integrin ß1 markedly enhanced IGF1 binding to ß1, suggesting that the WPNSDP sequence is involved in IGF1 recognition. WT IGF1 induced α6ß4-IGF1-IGF1R ternary complex formation, whereas R36E/R37E did not. When cells were attached to matrix, exogenous IGF1 or α6ß4 expression had little or no effect on intracellular signaling. When cell-matrix adhesion was reduced (in poly(2-hydroxyethyl methacrylate-coated plates), IGF1 induced intracellular signaling and enhanced cell survival in an α6ß4-dependent manner. Also IGF1 enhanced colony formation in soft agar in an α6ß4-dependent manner. These results suggest that IGF binding to α6ß4 plays a major role in IGF signaling in anchorage-independent conditions, which mimic the in vivo environment, and is a novel therapeutic target.

A novel fibroblast growth factor-1 (FGF1) mutant that acts as an FGF antagonist.

BACKGROUND: Crosstalk between integrins and FGF receptors has been implicated in FGF signaling, but the specifics of the crosstalk are unclear. We recently discovered that 1) FGF1 directly binds to integrin alphavbeta3, 2) the integrin-binding site and FGF receptor (FGFR) binding site are distinct, and 3) the integrin-binding-defective FGF1 mutant (R50E) is defective in inducing FGF signaling although R50E still binds to FGFR and heparin and induces transient ERK1/2 activation. PRINCIPAL FINDINGS: We tested if excess R50E affect DNA synthesis and cell survival induced by WT FGF1 in BaF3 mouse pro-B cells expressing human FGFR1. R50E suppressed DNA synthesis and cell proliferation induced by WT FGF1. We tested if WT FGF1 and R50E generate integrin-FGF1-FGFR ternary complex. WT FGF1 induced ternary complex formation (integrin-FGF-FGFR1) and recruitment of SHP-2 to the complex in NIH 3T3 cells and human umbilical endothelial cells, but R50E was defective in these functions. It has been reported that sustained ERK1/2 activation is integrin-dependent and crucial to cell cycle entry upon FGF stimulation. We thus determined the time-course of ERK1/2 activation induced by WT FGF1 and R50E. We found that WT FGF1 induced sustained activation of ERK1/2, but R50E was defective in this function. CONCLUSIONS/SIGNIFICANCE: Our results suggest that 1) R50E is a dominant-negative mutant, 2) Ternary complex formation is involved in FGF signaling, 3) The defect of R50E to bind to integrin may be directly related to the antagonistic action of R50E. Taken together, these results suggest that R50E has potential as a therapeutic in cancer.

Expression of heme oxygenase-1 in human leukemic cells and its regulation by transcriptional repressor Bach1.

Heme oxygenase (HO)-1 has anti-oxidative, anti-inflammatory, and anti-apoptotic activities. However, little is known about the regulation of HO-1 in human primary acute myeloid leukemia (AML) cells. Here we investigated the expression of HO-1 in primary and established AML cells as well as other types of leukemic cells and normal monocytes, and its regulatory mechanism by the transcriptional repressor, BTB and CNC homology 1 (Bach1), and the activator, nuclear factor erythroid-derived 2 related factor 2 (Nrf2). Leukemic cell lines such as U937 expressed little HO-1, whereas most freshly isolated AML cells and monocytes expressed substantial amounts of HO-1, along with Bach1 and Nrf2. When U937 cells were treated with phorbol myristate acetate (PHA) or gamma-interferon, they significantly expressed both HO-1 and Bach1, like primary AML cells. Treatment with lipopolysaccharide (LPS) enhanced HO-1 expression in U937 cells but suppressed it in primary monocytes and PMA-treated U937 cells. In HO-1-expressing cells, Bach1 was localized in the cytoplasm, but Nrf2 was localized in the nuclei. Chromatin immunoprecipitation assay of these cells revealed the preferential binding of Nrf2 over Bach1 to Maf-recognition elements, the enhancer regions of the HO-1 gene. The downregulation of the HO-1 gene with siRNA increased a cytotoxic effect of an anticancer drug on primary AML cells, whereas the downregulation of Bach1 increased HO-1 expression, leading to enhanced survival. These and other results show that Bach1 plays a critical role in regulating HO-1 gene expression in AML cells and its expression suppresses their survival by downregulating HO-1 expression. Thus, functional upregulation of Bach1 is a potential strategy for antileukemic therapy.

Serum HO-1 is useful to make differential diagnosis of secondary hemophagocytic syndrome from other similar hematological conditions.

Heme oxygenase (HO)-1, a heme-degrading enzyme inducible by various stimuli, plays a key role in the regulation of inflammatory response in monocytes/macrophages. The serum HO-1 level is remarkably increased in patients with secondary hemophagocytic syndrome (HPS) or adult-onset Still's disease. We measured serum HO-1 levels in patients with a variety of hematological diseases, including secondary HPS, by means of ELISA. Serum HO-1 levels were significantly higher in 22 patients with HPS (134.7 +/- 116.2 ng/mL, P < 0.0001) at diagnosis than in 80 patients with other hematological diseases. The most effective cutoff point between HPS and other conditions was 14.5 ng/mL, with 100.0% sensitivity and 96.3% specificity. In HPS patients, the serum HO-1 levels showed the highest correlation with serum ferritin (r = 0.682, P = 0.0005), which reflects the disease activity of HPS. Moreover, both HO-1 and ferritin levels were reduced in parallel after successful treatment in patients with HPS, irrespective of underlying diseases. However, HO-1 levels were not elevated in patients with other causes of hyperferritinemia. These data demonstrate that serum HO-1 can distinguish secondary HPS from other hematological diseases, including those associated with hyperferritinemia.

The direct binding of insulin-like growth factor-1 (IGF-1) to integrin alphavbeta3 is involved in IGF-1 signaling.

It has been proposed that ligand occupancy of integrin alphavbeta3 with extracellular matrix ligands (e.g. vitronectin) plays a critical role in insulin-like growth factor-1 (IGF-1) signaling. We found that expression of alphavbeta3 enhanced IGF-1-induced proliferation of Chinese hamster ovary cells in serum-free conditions (in the absence of vitronectin). We hypothesized that the direct integrin binding to IGF-1 may play a role in IGF-1 signaling. We demonstrated that alphavbeta3 specifically and directly bound to IGF-1 in cell adhesion, enzyme-linked immunosorbent assay-type binding, and surface plasmon resonance studies. We localized the amino acid residues of IGF-1 that are critical for integrin binding by docking simulation and mutagenesis. We found that mutating two Arg residues at positions 36 and 37 in the C-domain of IGF-1 to Glu (the R36E/R37E mutation) effectively reduced integrin binding. Interestingly, although the mutant still bound to IGF1R, it was defective in inducing IGF1R phosphorylation, AKT and ERK1/2 activation, and cell proliferation. Furthermore wild type IGF-1 mediated co-precipitation of alphavbeta3 and IGF1R, whereas the R36E/R37E mutant did not, suggesting that IGF-1 mediates the interaction between alphavbeta3 and IGF1R. These results suggest that the direct binding to IGF-1 to integrin alphavbeta3 plays a role in IGF-1 signaling through ternary complex formation (alphavbeta3-IGF-IGF1R), and integrin-IGF-1 interaction is a novel target for drug discovery.

Direct binding of integrin alphavbeta3 to FGF1 plays a role in FGF1 signaling.

Integrins play a role in fibroblast growth factor (FGF) signaling through cross-talk with FGF receptors (FGFRs), but the mechanism underlying the cross-talk is unknown. We discovered that FGF1 directly bound to soluble and cell-surface integrin alphavbeta3 (K(D) about 1 microm). Antagonists to alphavbeta3 (monoclonal antibody 7E3 and cyclic RGDfV) blocked this interaction. alphavbeta3 was the predominant, if not the only, integrin that bound to FGF1, because FGF1 bound only weakly to several beta1 integrins tested. We presented evidence that the CYDMKTTC sequence (the specificity loop) within the ligand-binding site of beta3 plays a role in FGF1 binding. We found that the integrin-binding site of FGF1 overlaps with the heparin-binding site but is distinct from the FGFR-binding site using docking simulation and mutagenesis. We identified an FGF1 mutant (R50E) that was defective in integrin binding but still bound to heparin and FGFR. R50E was defective in inducing DNA synthesis, cell proliferation, cell migration, and chemotaxis, suggesting that the direct integrin binding to FGF1 is critical for FGF signaling. Nevertheless, R50E induced phosphorylation of FGFR1 and FRS2alpha and activation of AKT and ERK1/2. These results suggest that the defect in R50E in FGF signaling is not in the initial activation of FGF signaling pathway components, but in the later steps in FGF signaling. We propose that R50E is a useful tool to identify the role of integrins in FGF signaling.

Use of bepridil in combination with Ic antiarrhythmic agent in converting persistent atrial fibrillation to sinus rhythm.

BACKGROUND: It has been reported that bepridil is as good as amiodarone in converting persistent atrial fibrillation (AF) to sinus rhythm (SR). The conversion effect of bepridil alone is not always satisfactory, however. The efficacy of pharmacological cardioversion by the combination of bepridil and a class Ic antiarrhythmic drug for persistent AF is studied. METHODS AND RESULTS: The participants comprised 37 consecutive patients in whom pharmacological cardioversion was conducted to treat persistent AF (duration 22.5+/-29.6 months). Each patient first received a class Ia or Ic antiarrhythmic drug, then bepridil alone, then a combined therapy of bepridil at 200 mg/day with a class Ic antiarrhythmic drug at a routine dose. Unaccompanied use of any of the antiarrhythmic drugs achieved pharmacological cardioversion in 14 (38%) of the 37 patients (single therapy group), whereas SR was restored by combination of bepridil and a class Ic antiarrhythmic drug in 22 (combined therapy group) of the remaining 23 patients. The duration of AF was significantly longer in the combined therapy group than in the single therapy group (28.3+/-31.0 vs 7.3+/-4.1 months). CONCLUSION: Combined therapy of bepridil and a class Ic antiarrhythmic drug is efficient for pharmacological cardioversion of refractory long-lasting persistent AF.

Affixin activates Rac1 via betaPIX in C2C12 myoblast.

Affixin/beta-parvin is an integrin-linked kinase (ILK)-binding focal adhesion protein highly expressed in skeletal muscle and heart. To elucidate the possible role of affixin in skeletal muscle, we established stable C2C12 cell line expressing T7-tagged human affixin (C2C12-affixin cells). Exogenous expression of affixin promotes lamellipodium formation where affixin, ILK alphap21-activated kinase (PAK)-interactive exchange factor (PIX) and betaPIX accumulate. The association of affixin and betaPIX was confirmed by immunoprecipitation and pull down assay. In C2C12-affixin cells, an increased level of activated Rac1 but not Cdc42 was observed, and mutant betaPIX lacking guanine nucleotide exchange factor activity inhibited lamellipodium formation. These results suggest that affixin is involved in reorganization of subsarcolemmal cytoskeletal actin by activation of Rac1 through alpha and betaPIXs in skeletal muscle.

[Pure red cell aplasia in patients treated with recombinant erythropoietin for anemia due to chronic renal disease].

It has been reported in the Western literature that patients with chronic renal disease have developed anti-erythropoietin (EPO) antibody-related pure red cell aplasia (PRCA). To investigate the incidence of anti-EPO antibody-related PRCA in Japan, we designed a questionnaire survey based on previous reports of patients who had PRCA during treatment with EPO. Thirteen of 17 patients were evaluated in this study. In all 13 patients, EPO delivery was via injection, 9 subcutaneously, 2 intravenously and 2 with a combination of the 2 methods. Three of 4 patients treated with subcutaneous EPO administration were positive for anti-EPO antibodies, but all patients treated by intravenous injection were negative. The EPO was stopped in 8 patients after the onset of PRCA, and immunosuppressive therapy with prednisolone and/or cyclosporine was administered in 12 patients. An improvement in PRCA was obtained in 12 patients. It was suspected that previous reports in Japan may have included both anti-EPO antibody-associated PRCA and incidental cases. Furthermore, subcutaneous administration of EPO may effect the production of anti-EPO antibodies.

Prognostic value of integrin beta1-ILK-pAkt signaling pathway in non-small cell lung cancer.

Cell adhesion signaling via the integrin-extracellular matrix connection plays a critical role in the growth and survival of normal adhering cells. Integrin-linked kinase is a ubiquitously expressed serine-threonine protein kinase capable of interacting with the cytoplasmic domains of integrin beta1 and beta3 and plays a critical role of an interface between integrin and the cytoskeleton in integrin-dependent cell adhesion, spreading, and cell shape change. In this study, we evaluated integrin beta1, integrin-linked kinase, and phosphorylated-Akt (Ser 473; pAkt) expressions in 118 consecutive non-small cell lung cancer tissue samples surgically resected between 1997 and 2000. As a result, we identified the specific subset of strong membranous staining of integrin beta1, strong cytoplasmic staining of integrin-linked kinase, and strong cytoplasmic staining with a granular pattern of pAkt in the non-small cell lung cancer tissue samples. In addition, we provide evidence that integrin-linked kinase, integrin beta1, and the activated form of Akt are mutually associated with poor prognosis in non-small cell lung cancer and that the simultaneous overexpression of these proteins is an independent prognostic factor (hazard ratio, 2.771; P = .003) comparable with standard prognostic factors such as T factor and lymphatic invasion by multivariate analysis. Thus, further studies of the integrin beta1-integrin-linked kinase-pAkt signaling pathway may provide a novel prognostic marker and therapeutic target for non-small cell lung cancer.

[Multiple myeloma presenting as cavernous sinus syndrome].

We report on a 70-year-old male who developed cavernous sinus syndrome as the initial symptom of multiple myeloma. He was admitted with diplopia and ptosis in October 2004. The diagnosis of multiple myeloma and cavernous sinus syndrome due to a gross mass at the sinus base were made. Cerebral computed tomography revealed that the lesion occupied the sphenoid sinus and involved the oculomoter nerve. He underwent local irradiation of the mass followed by systemic chemotherapy. The symptoms caused by the mass disappeared after the treatment. Clinicians need to be aware of the rare manifestation of multiple myeloma.

Non-Hodgkin's lymphoma presenting as multiple bone lesions and hypercalcemia.

We report a rare case of a patient with non-Hodgkin's lymphoma who developed multiple bone lesions and hypercalcemia. A 50-year-old woman complained of drowsiness and multiple bone pain on admission. Radiographic examination revealed multiple bone fractures and osteolytic lesions. She was diagnosed with diffuse large B cell lymphoma by biopsy of an inguinal lymph node. Elevation of parathyroid hormone-related protein (PTHrP) and hypercalcemia were confirmed pretreatment, and those serum levels decreased during chemotherapy for lymphoma. However, the disease was resistant to chemotherapy combined with rituximab. These findings suggest that hypercalcemia is associated with PTHrP and the prognosis of patients with bone lymphoma in advanced stage is poor, although it is thought to be a relatively favorable prognosis in localized primary lymphoma of bone.

The gamma-parvin-integrin-linked kinase complex is critically involved in leukocyte-substrate interaction.

Leukocyte extravasation is an important step of inflammation, in which integrins have been demonstrated to play an essential role by mediating the interaction of leukocytes with the vascular endothelium and the subendothelial extracellular matrix. Previously, we identified an integrin-linked kinase (ILK)-binding protein affixin (beta-parvin), which links initial integrin signals to rapid actin reorganization, and thus plays critical roles in fibroblast migration. In this study, we demonstrate that gamma-parvin, one of three mammalian parvin family members, is specifically expressed in several lymphoid and monocytic cell lines in a complementary manner to affixin. Like affixin, gamma-parvin directly associates with ILK through its CH2 domain and colocalizes with ILK at focal adhesions as well as the leading edge of PMA-stimulated U937 cells plated on fibronectin. The overexpression of the C-terminal fragment containing CH2 domain or the depletion of gamma-parvin by RNA interference inhibits the substrate adhesion of MCP-1-stimulated U937 cells and the spreading of PMA-stimulated U937 cells on fibronectin. Interestingly, the overexpression of the CH2 fragment or the gamma-parvin RNA interference also disrupts the asymmetric distribution of PTEN and F-actin observed at the very early stage of cell spreading, suggesting that the ILK-gamma-parvin complex is essential for the establishment of cell polarity required for leukocyte migration. Taken together with the results that gamma-parvin could form a complex with some important cytoskeletal proteins, such as alphaPIX, alpha-actinin, and paxillin as demonstrated for affixin and actopaxin (alpha-parvin), the results in this study suggest that the ILK-gamma-parvin complex is critically involved in the initial integrin signaling for leukocyte migration.

Does high-power computed tomography scanning equipment affect the operation of pacemakers?

BACKGROUND: Computed tomography (CT) is widely used in clinical practice, but there has not been a detailed report of its effect on the functioning of pacemakers. METHODS AND RESULTS: During CT, ECGs were recorded in 11 patients with pacemakers and the electromagnetic field in the CT room was also measured. The effect of CT on a pacemaker was also investigated in a human body model with and without shielding by rubber or lead. Transient malfunctions of pacemakers during CT occurred in 6 of 11 patients. The model showed that malfunctioning of the pacemaker was induced by CT scanning and this was prevented by lead but not by rubber. The alternating electrical field was 150 V/m on the CT scanning line, which was lower than the level influencing pacemaker functions. The alternating magnetic field was 15 muT on the CT scanning line, which was also lower than the level influencing pacemaker functions. CONCLUSIONS: Malfunctions of the pacemaker during CT may be caused by diagnostic radiant rays and although they are transient, the possibility of lethal arrhythmia cannot be ignored.

Up-regulation of integrin-linked kinase activity in rat mesangioproliferative glomerulonephritis.

This study investigated whether integrin-linked kinase (ILK) is involved in the pathogenesis of chronic glomerulonephritis (GN) by analyzing the expression and activity of glomerular ILK in a chronic rat model of mesangioproliferative GN. Double immunostaining of kidneys obtained at different time points with glomerular cell-specific markers revealed that ILK was primarily expressed by glomerular epithelial cells, and weakly by mesangial cells (MCs) and endothelial cells in control rats, but dramatically increased in a typical mesangial pattern at days 21 and 28 of GN. Semiquantitative assessment indicated that the level of glomerular ILK expression closely parallels the level of accumulation of glomerular extracellular matrix (ECM) as well as fibronectin (FN). Immunoprecipitation and kinase activity assays using isolated nephritic glomeruli indicated a striking increase of ILK activity on days 21 and 28 of GN. Further, cultured rat MCs overexpressing kinase-deficient ILK diminished FN assembly and collagen matrix remodeling as compared with control transfectants. The results showed that glomerular ILK expression and activity are markedly increased in an experimental model of chronic GN. Increased activity of ILK in MCs may contribute to the development of chronic mesangial alterations leading to glomerular scarring.

Idiopathic thrombocytopenic purpura and myasthenia gravis after fludarabine treatment for chronic lymphocytic leukemia.

We report a patient with chronic lymphocytic leukemia (CLL) who developed idiopathic thrombocytopenic purpura (ITP) and myasthenia gravis (MG) after fludarabine therapy. ITP developed after 6 cycles of fludarabine treatment, and MG occurred 2 months after the onset of ITP. MG was successfully treated with immunosuppressive therapy and plasma exchange, while rituximab was effective for CLL and ITP. Fludarabine seemed to have an important role in the onset of ITP and MG in this case.

Dysferlin interacts with affixin (beta-parvin) at the sarcolemma.

The dysferlin gene is defective in Miyoshi myopathy (MM) and limb girdle muscular dystrophy type 2B (LGMD2B). Dysferlin is a sarcolemmal protein that is implicated in calcium-dependent membrane repair. Affixin (beta-parvin) is a novel, integrin-linked kinase-binding protein that is involved in the linkage between integrin and the cytoskeleton. Here we show that affixin is a dysferlin binding protein that colocalizes with dysferlin at the sarcolemma of normal human skeletal muscle. The immunoreactivity of affixin was reduced in sarcolemma of MM and LGMD2B muscles, although the total amount of the affixin protein was normal. Altered immunoreactivity of affixin was also observed in other muscle diseases including LGMD1C, where both affixin and dysferlin showed quite similar changes with a reduction of sarcolemmal staining with or without cytoplasmic accumulations. Colocalization of dysferlin and affixin was confirmed by immunofluorescence analysis using dysferlin-expressing C2 myoblasts. Wild-type and mutant dysferlin colocalized with endogenous affixin. The interaction of dysferlin and affixin was confirmed by immunoprecipitation study using normal human and mouse skeletal muscles. Using immunoprecipitation with deletion mutants of dysferlin, we have identified that C-terminal region of dysferlin is an apparent binding site for affixin. We also found N-terminal calponin homology domain of affixin as a binding site for dysferlin. Our results suggest that affixin may participate in membrane repair with dysferlin.