Big mitogen-activated protein kinase 1 (BMK1)/extracellular signal regulated kinase 5 (ERK5) is involved in platelet-derived growth factor (PDGF)-induced vascular smooth muscle cell migration

Big mitogen-activated protein kinase 1 (BMK1), also known as extracellular signal-regulated kinase 5 (ERK5), is a newly identified member of the mitogen-activated protein (MAP) kinase family. Recently, several studies have suggested that BMK1 plays an important role in the pathogenesis of cardiovascular disease. To clarify the pathophysiological significance of BMK1 in the process of vascular remodeling, we explored the molecular mechanisms of BMK1 activation in vascular smooth muscle cells (VSMCs). From the results of co-immunoprecipitation and immunoblotting analyses, it was found that platelet-derived growth factor (PDGF), a known potent mitogen, activated BMK1 and triggered the Gab1-SHP-2 interaction in rat aortic smooth muscle cells (RASMCs). The abrogation of SHP-2 phosphatase activity by transfection of the SHP-2-C/S mutant suppressed PDGF-stimulated BMK1 activation. Infection with an adenoviral vector expressing dominant-negative MEK5alpha, which can suppress PDGF-stimulated BMK1 activation to the control level, inhibited PDGF-induced RASMC migration. Moreover, we observed an increase of BMK1 activation in injured mouse femoral arteries. From these findings, it is suggested that BMK1 activation leads to VSMC migration induced by PDGF via Gab1-SHP-2 interaction, and that BMK1-mediated VSMC migration may play a role in the pathogenesis of vascular remodeling.     

Clinical study on norfloxacin in children

Norfloxacin (NFLX, AM-715), a new synthetic antibacterial agent, was administered to 18 child patients with infectious diseases. The patients included 5 boys and 13 girls from 3 to 14 years of ages. They were given orally dosage ranging 5.2-17.9 mg/kg/day for 4 to 14 days. Clinical efficacies were excellent in 1 case, good in 16 cases, unknown in 1 case, hence the total efficacy rate was determined to be 100%. There were no cases which showed side effects of the drug and no abnormal laboratory test values were observed during the treatment.     

Decellularized ureter for tissue-engineered small-caliber vascular graft

Previous attempts to create small-caliber vascular prostheses have been limited. The aim of this study was to generate tissue-engineered small-diameter vascular grafts using decellularized ureters (DUs). Canine ureters were decellularized using one of four different chemical agents [Triton-X 100 (Tx), deoxycholate (DCA), trypsin, or sodium dodecyl sulfate (SDS)] and the histology, residual DNA contents, and immunogenicity of the resulting DUs were compared. The mechanical properties of the DUs were evaluated in terms of water permeability, burst strength, tensile strength, and compliance. Cultured canine endothelial cells (ECs) and myofibroblasts were seeded onto DUs and evaluated histologically. Canine carotid arteries were replaced with the EC-seeded DUs (n = 4). As controls, nonseeded DUs (n = 5) and PTFE prostheses (n = 4) were also used to replace carotid arteries. The degree of decellularization and the maintenance of the matrix were best in the Tx-treated DUs. Tx-treated and DCA-treated DUs had lower remnant DNA contents and immunogenicity than the others. The burst strength of the DUs was more than 500 mmHg and the maximum tensile strength of the DUs was not different to that of native ureters. DU compliance was similar to that of native carotid artery. The cell seeding test resulted in monolayered ECs and multilayered alpha-smooth muscle actin-positive cells on the DUs. The animal implantation model showed that the EC-seeded DUs were patent for at least 6 months after the operation, whereas the nonseeded DUs and PTFE grafts become occluded within a week. These results suggest that tissue-engineered DUs may be a potential alternative conduit for bypass surgery.     

Role of JAK2 signal transductional pathway in activation and survival of human peripheral eosinophils by interferon-gamma (IFN-gamma)

The purpose of this study was to determine whether the JAK pathway is involved in eosinophil activation and survival through IFN-gamma receptor signalling in human peripheral eosinophils. Eosinophils were purified from the blood of six atopic disease patients by anti-CD16 magnetic bead-negative selection. IFN-gamma significantly up-regulated survival and CD69 expression in 24-48 h cultured eosinophils. Further, IFN-gamma induced tyrosine phosphorylation of JAK2 in eosinophils, as indicated by Western blot analysis. Finally, the specific JAK2 inhibitor AG-490 inhibited the tyrosine phosphorylation of JAK2, IFN-gamma-induced survival and CD69 expression in eosinophils. In conclusion, these results indicate that IFN-gamma induces eosinophil survival and CD69 expression through the activation of JAK2 in peripheral eosinophils, suggesting that JAK2 may play a significant role in eosinophil regulation by IFN-gamma-IFN-gammaR interaction.     

Homologous carcinosarcoma of the uterine corpus--report of a case and review of the literature in Japan

A 59-year-old woman with leukorrhea. Aspiration smears were obtained from the uterine cavity. The dominant cellular components were fibrogenic sarcomatous cells, which had ill-defined lacy cytoplasm and a single nucleus with finely granular chromatin. There were occasional naked giant cells, and intracytoplasmic eosinophilic granules. Another infrequent cellular component was adenocarcinoma cells. Histopathologically, adenocarcinoma and spindle cell sarcoma were equivalently identified. Twenty-two cases of homologous carcinosarcoma of the uterine corpus were reviewed cytologically in Japan. Cytodiagnosis before treatment was positive for malignancy of carcinosarcoma in 28.6%. Characteristic cytological findings of this case were the presence of flat sheets of atypical cells with broad cytoplasm. These findings suggest epithelial features. However, the finely granular chromatin pattern and smooth nuclear membrane indicate sarcomatous cells.     

Alpha1beta1 integrin-mediated collagen matrix remodeling by rat mesangial cells is differentially regulated by transforming growth factor-beta and platelet-derived growth factor-BB

Pathologic remodeling of mesangial matrix after glomerular injury is the central biologic feature of glomerular scarring (sclerosis). Transforming growth factor-beta (TGF-beta) and platelet-derived growth factor (PDGF)-BB have been implicated in the development of glomerular scarring in rat and human glomerulonephritis. To clarify molecular and cellular mechanisms involved in abnormal mesangial remodeling, this study focused on the role of alpha1beta1 integrin, a collagen/laminin receptor, in rat mesangial cells, using collagen gel contraction as an experimental model of in vivo collagen matrix remodeling and scar formation. In addition, the influence of TGF-beta and PDGF-BB on mesangial cell (MC)-mediated collagen gel contraction in association with the alpha1beta1 integrin expression was evaluated. Integrin function blocking studies using anti-alpha1, beta1 subunit antibodies indicated that MC-alpha1beta1 integrin is essentially required not only for collagen-dependent adhesion/migration, but also for gel contraction. Protein synthesis and mRNA analysis experiments demonstrated that TGF-beta, but not PDGF-BB, increases the expression of alpha1beta1 integrin in mesangial cells cultured on plastic surface and in collagen gels. The upregulation of alpha1beta1 integrin expression by TGF-beta correlated with increases in gel contraction and collagen-dependent adhesion but not migration of mesangial cells. On the other hand, PDGF-BB enhanced MC-mediated gel contraction and migration without affecting cell adhesion to collagen I. Growth factor-induced collagen-dependent adhesion, migration, and gel contraction were significantly attenuated by incubation with anti-alpha1, beta1 subunit antibodies. Thus, these data indicate that alpha1beta1 integrin-mediated collagen matrix remodeling can be modulated by TGF-beta and PDGF-BB via different mechanisms. Alpha1 integrin-mediated mesangial matrix remodeling induced by TGF-beta or PDGF-BB may be a pathogenic mechanism leading to glomerular scarring.     

Feasibility and pharmacokinetic study of a chimeric anti-CD20 monoclonal antibody (IDEC-C2B8, rituximab) in relapsed B-cell lymphoma

Background: In clinical trials in the USA, IDEC-C2B8 (a mouse-humanchimeric anti-CD20 monoclonal antibody) has demonstrated high response rateswith only mild toxic effects in relapsed B-cell lymphoma at a dose of fourweekly 375 mg/m² infusions. The aim of the present trial wasto determine whether or not this dose is practically applicable to Japanesepatients with relapsed B-cell lymphoma with respect to safety,pharmacokinetics and efficacy.Patients and methods: Patients with relapsed CD20+ B-cell lymphomareceived intravenous infusions of IDEC-C2B8 once a week for four weeks. Atotal of 12 patients (four at 250 mg/m² and eight at 375mg/m²) were enrolled.Results: All 11 eligible patients treated with either dose leveltolerated IDEC-C2B8 well. Commonly observed adverse drug reactions weregrades 1 or 2 non-hematologic toxicities during the infusion, consistingmostly of flu-like symptoms and skin reactions. All of the observedhematologic toxicities were of grade 3 or less, and transient. A rapid andsustained B-cell decrease in peripheral blood was observed, but noinfectious episodes were encountered. Human anti-mouse and anti-chimericantibodies were not detected. Of the 11 eligible patients (eight withfollicular, two with diffuse large-cell and one with mantle cell lymphoma),two showed a complete response and five showed a partial response, and allof the seven responders had lymphoma with follicular histology. Apharmacokinetic analysis showed that the elimination half-life (T1/2) ofIDEC-C2B8 was 445 ± 361 hours, and that the serum antibody levelsincreased in parallel with the course of infusions, and in most patients wasstill measurable at three months.Conclusions: The dose of four weekly 375 mg/m² infusionsof IDEC-C2B8 is safe and effective in Japanese patients with relapsed B-celllymphoma. Further studies evaluating IDEC-C2B8 are warranted.     

Complementarity determining region-III is a useful molecular marker for the evaluation of minimal residual disease in mantle cell lymphoma

Bone marrow (BM) and peripheral blood (PB) involvement in 10 patients with mantle cell lymphoma (MCL) was analysed by a polymerase chain reaction (PCR)-mediated RNase protection assay. The complementarity determining regions (CDR)-III of all 10 MCLs examined was amplified efficiently with consensus V_H and J_H primers by PCR, and BM and/or PB involvement was evaluated by RNase protection assay in all 10 patients examined. Our assay showed BM and/or PB of the entire group to have neoplastic cells at presentation, despite the fact that eight patients were found to have BM and/or PB involvement on the basis of morphological examination and/or surface marker analysis. We also examined minimal residual disease (MRD) after conventional chemotherapy, and detected MRD in a patient in complete remission (CR). Although previous studies have shown that t(11;14) breakpoint amplification by PCR was only applicable to about 30–40% of cases, the present study indicates that CDR-III is a useful molecular marker and the PCR-mediated RNase protection assay is a good tool for the evaluation of MRD in MCL. It is suggested that BM and PB of MCL patients are quite frequently involved at presentation and even after conventional chemotherapy at the molecular level.     

Comprehensive clinical studies in 34 patients with molecularly defined UPD(14)pat and related conditions (Kagami–Ogata syndrome)

Paternal uniparental disomy 14 (UPD(14)pat) and epimutations and microdeletions affecting the maternally derived 14q32.2 imprinted region lead to a unique constellation of clinical features such as facial abnormalities, small bell-shaped thorax with a coat-hanger appearance of the ribs, abdominal wall defects, placentomegaly, and polyhydramnios. In this study, we performed comprehensive clinical studies in patients with UPD(14)pat (n=23), epimutations (n=5), and microdeletions (n=6), and revealed several notable findings. First, a unique facial appearance with full cheeks and a protruding philtrum and distinctive chest roentgenograms with increased coat-hanger angles to the ribs constituted the pathognomonic features from infancy through childhood. Second, birth size was well preserved, with a median birth length of ±0 SD (range, −1.7 to +3.0 SD) and a median birth weight of +2.3 SD (range, +0.1 to +8.8 SD). Third, developmental delay and/or intellectual disability was invariably present, with a median developmental/intellectual quotient of 55 (range, 29–70). Fourth, hepatoblastoma was identified in three infantile patients (8.8%), and histological examination in two patients showed a poorly differentiated embryonal hepatoblastoma with focal macrotrabecular lesions and well-differentiated hepatoblastoma, respectively. These findings suggest the necessity of an adequate support for developmental delay and periodical screening for hepatoblastoma in the affected patients, and some phenotypic overlap between UPD(14)pat and related conditions and Beckwith–Wiedemann syndrome. On the basis of our previous and present studies that have made a significant contribution to the clarification of underlying (epi)genetic factors and the definition of clinical findings, we propose the name ‘Kagami–Ogata syndrome'' for UPD(14)pat and related conditions.