AB0249 SAFETY OF BARICITINIB IN JAPANESE PATIENTS WITH RHEUMATOID ARTHRITIS (RA): THE 2020 INTERIM REPORT FROM ALL-CASE POST MARKETING SURVEILLANCE IN CLINICAL PRACTICE

Background:

An all-case post marketing surveillance (PMS) of baricitinib (Bari), that started in Sep 2017, collects safety and effectiveness for the first 24 wks of treatment and continues to collect serious adverse events (SAEs) for 3 yrs.

Objectives:

To evaluate Bari safety in RA patients (pt) in clinical practice.

Methods:

We report pt baseline demographics and adverse events (AEs) up to 24 wks for pts whose case report files for 24-wk data were completed as of Jun 2020.

Results:

Data from 3445 pts were analyzed (females=80%, mean age=64yr, mean RA duration 12yr). Bari dose regimen was as follows: 4mg, 60%, 2mg, 27%, 4mg→2mg, 5%, 2mg→4mg, 5%, and others, 2%. Concomitant use of MTX and glucocorticoid was 65% and 48%, respectively. 74% continued treatment for 24 wks. AE and SAE were recognized in 887 (26%) and 122 pts (4%), respectively. 6 pts died of pneumonia, aspiration pneumonia, bacterial pneumonia, cerebral infarction/ILD/aspiration pneumonia, adenocarcinoma, and colorectal cancer. Major AEs were as follows: herpes zoster=3%, liver dysfunction=3%, serious infection=1%, anemia=1%, hyperlipidemia=1%, malignancy=0.3%, interstitial pneumonia=0.2%, MACE=0.1%, and VTE=0.1%.

Conclusion:

Data do not show new safety concerns and encourage guideline-compliant use of Bari.

Disclosure of Interests:

Takao Fujii Speakers bureau: Chugai Pharmaceutical Co. Ltd.; Eisai Co. Ltd; Eli Lilly Japan K.K.; Janssen Pharmaceutical K.K.; Ono Pharmaceutical Co. Ltd., Consultant of: Asahikasei Pharma Corp, Grant/research support from: Asahikasei Pharma Corp; AbbVie Japan GK; Chugai Pharmaceutical Co. Ltd., Eisai Co. Ltd; Eli Lilly Japan K.K.; Mitsubishi-Tanabe Pharma Co.; Ono Pharmaceutical Co., Ltd., Tatsuya Atsumi Speakers bureau: AbbVie Japan GK; Astellas Pharma Inc.; Bristol-Myers Squibb Co. Ltd; Chugai Pharmaceutical Co. Ltd.; Daiichi Sankyo Co. Ltd.; Eisai Co. Ltd.; Eli Lilly Japan K.K.; Mitsubishi Tanabe Pharma Co.; Pfizer Japan Inc.; Takeda Pharmaceutical Co. Ltd., UCB Japan Co. Ltd., Consultant of: AbbVie Japan GK; AstraZeneca plc.; Boehringer Ingelheim Co. Ltd.; Medical & Biological Laboratories Co. Ltd.; Novartis Pharma K.K.; Ono Pharmaceutical Co. Ltd.; Pfizer Japan Inc., Grant/research support from: Astellas Pharma Inc., Alexion Inc.; Chugai Pharmaceutical Co. Ltd., Daiichi Sankyo Co. Ltd., Mitsubishi Tanabe Pharma Co., Otsuka Pharmaceutical Co., Ltd.

Pfizer Japan Inc.; Takeda Pharmaceutical Co. Ltd., Nami Okamoto Speakers bureau: AbbVie Japan GK; Asahikasei Pharma Co.; AYUMI Pharmaceutical Co.

Eisai Co. Ltd; Bristol-Myers Squibb Co. Ltd.; Eli Lilly Japan K.K.; Mitsubishi-Tanabe Pharma Co.; Pfizer Japan Inc.

Sanofi K.K.; Chugai Pharmaceutical Co. Ltd.; Novartis Pharma Co.; Teijin Pharma Ltd.; Torii Pharmaceutical Co., Ltd., Nobunori Takahashi Speakers bureau: AbbVie Japan GK; Eisai Co. Ltd.; Mitsubishi Tanabe Pharma Co.; Pfizer Japan Inc.; Chugai Pharmaceutical Co., Ltd.; Eli Lilly Japan K.K.; Janssen Pharmaceutical K.K.; UCB Japan Co. Ltd.; Astellas Pharma Inc.; Bristol Myers Squibb Co. Ltd., Grant/research support from: Bristol Myers Squibb Co. Ltd., Naoto Tamura Speakers bureau: AbbVie Japan GK; Bristol Myers Squibb Co. Ltd.; Chugai Pharmaceutical Co. Ltd.; Eisai Co. Ltd.; Eli Lilly Japan K.K.; Glaxo Smith Kline K.K.; Janssen Pharmaceutical K.K.; Mitsubishi-Tanabe Pharma Co.; Novartis Pharma Co., Atsuo Nakajima: None declared, Ayako Nakajima Speakers bureau: AbbVie Japan GK; Actelion Pharmaceuticals Japan Ltd., Asahi Kasei Pharma Co., Astellas Pharma Inc., Ayumi Pharmaceutical Co., Bristol Myers Squibb Co., Ltd.,Chugai Pharmaceutical Co., Ltd., Eisai Co., Ltd., Eli Lilly Japan K.K., Glaxo Smith Kline K.K., Hisamitsu Pharmaceutical Co. Inc., Kyorin Pharmaceutical Co. Ltd., Mitsubishi Tanabe Pharma Co., Otsuka Pharmaceutical Co. Ltd., Pfizer Japan Inc., Teijin Pharma Ltd., Grant/research support from: Chugai Pharmaceutical Co., Ltd., Mitsubishi Tanabe Pharma Co., Pfizer Japan Inc., Hiroaki Matsuno Speakers bureau: Chugai Pharmaceutical Co., Ltd., Daiichi Sankyo Co., Ltd., Eli Lilly Japan K.K., Consultant of: Mochida Pharmaceutical Co., Ltd., Grant/research support from: Astellas Pharma Inc., Eli Lilly Japan K.K.; Janssen Pharmaceutical K.K, Naoto Tsujimoto Shareholder of: Eli Lilly, Employee of: Eli Lilly Japan K.K., Atsushi Nishikawa Shareholder of: Eli Lilly, Employee of: Eli Lilly Japan K.K., Taeko Ishii Shareholder of: Eli Lilly, Employee of: Eli Lilly Japan K.K., Tsutomu Takeuchi Speakers bureau: AbbVie Japan GK, Ayumi Pharmaceutical Co., Bristol Myers Squibb Co., Ltd., Chugai Pharmaceutical Co, Ltd. Daiichi Sankyo Co., Ltd. Eisai Co., Ltd. Eli Lilly Japan K.K.; Gilead Sciences, Inc. Janssen Pharmaceutical K.K.; Mitsubishi-Tanabe Pharma Co.; Novartis Pharma Co.; Pfizer Japan Inc.; Sanofi K.K.; UCB Japan Co., Ltd., Consultant of: AbbVie Japan GK, Astellas Pharma, Inc.; Chugai Pharmaceutical Co, Ltd.; Eli Lilly Japan K.K.; Eisai Co., Ltd.; Gilead Sciences, Inc.; Janssen Pharmaceutical K.K.; Mitsubishi-Tanabe Pharma Corp., Pfizer Japan Inc., Grant/research support from: AbbVie Japan GK, Asahikasei Pharma Corp., Chugai Pharmaceutical Co, Ltd., DNA Chip Research Inc.; Eisai Co., Ltd., Eli Lilly Japan K.K.; Mitsubishi-Tanabe Pharma Corp., UCB Japan Co., Ltd., Masataka Kuwana Speakers bureau: AbbVie Japan GK, Astellas Pharma Inc., Asahi Kasei Pharma Co., Boehringer-Ingelheim, Chugai Pharmaceutical Co., Ltd., Eisai Co., Ltd., Janssen Pharmaceutical K.K., Medical &Biological Laboratories Co., Ltd.; Mitsubishi Tanabe Pharma Co.; Mochida Pharmaceutical Co., Ltd., Nippon Shinyaku Co., Ltd.; Ono Pharmaceutical Co., Ltd.; Pfizer Japan Inc., Consultant of: Boehringer-Ingelheim, Chugai Pharmaceutical Co., Ltd., Corbus Pharmaceuticals Holdings, Inc.; Medical &Biological Laboratories Co., Ltd.; Mochida Pharmaceutical Co., Ltd., Grant/research support from: Boehringer-Ingelheim, Chugai Pharmaceutical Co., Ltd., Eisai Co., Ltd., Medical &Biological Laboratories Co., Ltd; Mitsubishi Tanabe Pharma Co., Ono Pharmaceutical Co., Ltd., Michiaki Takagi Speakers bureau: Yes, but sponsored lectures without COI in the academic meetings, only.

Fast and Reproducible Vascular Neointima Formation in the Hamster Carotid Artery: Effects of Trapidil and Captopril

Neointima formation was induced in the hamster carotid artery by mechanical intraluminal injury with a catheter covered with roughened dental cement. Neointimal thickening occurred as early as 7 days after denudation and further increased during the next 1 to 2 weeks. Proliferation indices of smooth muscle cells (SMCs) showed the highest proportion of proliferating cells in the media and neointima respectively 1 and 5 days after the vascular injury. Transmission and scanning electron microscopy of damaged carotid artery sections as well as immuno-histochemical stainings of von Willebrand factor (vWF) confirmed that reendothelialization was progressive and already complete on day 14, at which time the neointima formation was almost complete.

In order to pharmacologically characterize this model further, the effects on neointima formation of trapidil (triazolopyrimidine), a platelet-derived growth factor (PDGF) antagonist, and captopril, an angiotensin converting enzyme inhibitor, were investigated. Trapidil administered orally twice daily at total doses of 25, 50 and 100 mg/kg/day, started 3 days prior to infliction of injury and up to 7 or 14 days after the catheterization, significantly reduced neointima formation. Captopril administered orally three times daily at a total dose of 100 mg/kg/day, equally reduced neointima formation, with 100 mg/kg/day trapidil being more effective than 100 mg/kg/day captopril 7 days after injury. When the treatment by either one of these drugs was arrested on day 7, neointima formation resumed quickly.

The hamster appears to be a small, reproducible and fast model for the study of SMC proliferation, requiring only relatively small amounts of experimental drugs. The model furthermore is sensitive to substances known to reduce neointima formation in other animal models.

Body weight and dysautonomia in early Parkinson's disease

OBJECTIVES

Patients with Parkinson's disease (PD) begin to lose weight several years before diagnosis, which suggests weight variation is associated with some factor(s) that precede the onset of motor symptoms. This study aimed to investigate the association of autonomic nervous system with body weight in patients with PD.

MATERIALS AND METHODS

The subjects were 90 patients with early de novo PD. We examined the associations of body mass index (BMI) with sympathetic nervous activity reflected in orthostatic intolerance or cardiac uptake of ¹²³ I-metaiodobenzylguanidine and parasympathetic nervous activity reflected in constipation or heart rate variability (HRV).

RESULTS

Twelve patients (13.3%) were overweight (BMI>25 kg/m² ), 62 patients (68.9%) were normal-weight (18.5≦BMI<25 kg/m² ), and 16 patients (17.8%) were underweight (BMI<18.5 kg/m² ). Underweight patients had greater disease severity and decrease in blood pressure on head-up tilt-table testing, higher cardiac washout ratio of ¹²³ I-metaiodobenzylguanidine, and lower HRV and complained of constipation more often than those with normal-weight or overweight patients. On multiple regression analyses, the correlation of these variables with BMI maintained statistical significance after adjustment for age, sex, symptom duration, and motor subtype.

CONCLUSIONS

Dysautonomia and disease severity are closely related to body weight independently of age, sex, symptom duration, and motor subtype. Dysautonomia may play a partial role on weight variation in the early stage of PD.

Effect of interfacial structure on bioinert properties of poly(2-methoxyethyl acrylate)/poly(methyl methacrylate) blend films in water

Poly(2-methoxyethyl acrylate) (PMEA) segregation to the water interface in a blend film disturbed the network structure of water molecules, resulting in effective suppression of platelet adhesion.

A synthetic peptide derived from staphylokinase enhances plasminogen activation by tissue-type plasminogen activator

BACKGROUND

A synthetic nonadecapeptide (SP; GPYLMVNVTGVDGKGNELL) previously enhanced the activation of plasminogen by the SAK/plasmin complex.

OBJECTIVES

To identify the binding site for SP on plasminogen and elucidate the effects of SP on plasminogen activation by the tissue-type plasminogen activator (t-PA).

METHODS

The effects of SP on plasminogen activation were estimated using a chromogenic substrate and from the cleavage of plasmin on SDS-PAGE under reduced conditions. The binding to SP of various peptides derived from the amino acid sequence of plasminogen was analyzed with an IAsys biosensor. The SP-mediated structural change to plasminogen was analyzed by circular dichroism (CD) spectroscopy. The thrombolytic effects of SP were examined using a mouse model of thrombosis.

RESULTS

SP enhanced the activation of plasminogen by t-PA. The catalytic efficiency (k(cat)/K(m)) of Glu-plasminogen activation by t-PA was 11.4-fold higher in the presence than absence of SP. The binding of SP to plasminogen was greatly inhibited by a synthetic peptide, FEKDKYILQGVTSWGLG, located close to the C-terminal of the plasminogen B region. Near-ultraviolet CD spectra of the complex between SP and Glu-plasminogen significantly differed from those of Glu-plasminogen. When SP was administered in a mouse model of thrombosis, early recanalization was observed in a dose-dependent manner. However, SP did not cause recanalization in t-PA gene-deficient mice.

CONCLUSIONS

SP bound to the B region and promoted the activation of plasminogen by t-PA, and then induced effective thrombolysis.

Alpha2-antiplasmin is involved in the production of transforming growth factor beta1 and fibrosis

BACKGROUND

Fibrotic disease occurs in most tissues. Transforming growth factor (TGF)-beta is the major inducer of fibrosis. The fibrinolytic system is considered to play an important role in the degradation of extracellular matrices. However, the detailed mechanism of how this system affects fibrosis remains unclear.

METHODS AND RESULTS

We examined experimental fibrosis in mice with a deficiency of alpha(2)-antiplasmin (alpha2AP), which is a potent and specific plasmin inhibitor. We found that the lack of alpha2AP attenuated bleomycin-induced TGF-beta(1) synthesis and fibrosis. In addition, the production of TGF-beta(1) from the explanted fibroblasts of alpha2AP(-/-) mice decreased dramatically as compared to that in wild-type mice. Moreover, we found that alpha2AP specifically induces the production of TGF-beta(1) in fibroblasts.

CONCLUSION

The lack of alpha2AP attenuated TGF-beta(1) synthesis, thereby resulting in attenuated fibrosis. This is the first report to describe the crucial role that alpha2AP plays in TGF-beta(1) synthesis during the process of fibrosis. Our results provide new insights into the role of alpha2AP in fibrosis.

Lack of alpha2-antiplasmin improves cutaneous wound healing via over-released vascular endothelial growth factor-induced angiogenesis in wound lesions

BACKGROUND

The fibrinolytic system is supposed to play an important role in the degradation of extracellular matrices for physiological and pathological tissue remodeling; however, the detailed mechanism regarding how this system affects cutaneous wound healing remains to be clarified.

METHODS AND RESULTS

We performed experimental cutaneous wounding in mice with a deficiency of alpha(2)-antiplasmin (alpha(2)AP), which is a potent and specific plasmin inhibitor. We found that an accelerated wound closure was observed in alpha(2)AP-deficient (alpha(2)AP-/-) mice in comparison with wild type (WT) mice. Moreover, we observed that a greater increase of angiogenesis occurred in the process of wound healing in alpha(2)AP-/- mice than in the WT mice. Intriguingly, mRNA expression of vascular endothelial growth factor (VEGF), which is the best characterized positive regulator of angiogenesis, in wound lesions was found to show a greater increase in the early phase of the healing process in alpha(2)AP-/- mice than in WT mice. In addition, the amount of released-VEGF from the explanted fibroblasts of alpha(2)AP-/- mice increased dramatically more than in the WT mice. Finally, the intra-jugular administration of anti-VEGF antibody clearly suppressed the increased angiogenesis and accelerated wound closure in the wound lesion of alpha(2)AP-/- mice.

CONCLUSION

The lack of alpha(2)AP markedly causes an over-release of VEGF from the fibroblasts in cutaneous wound lesions, thereby inducing angiogenesis around the area, and thus resulting in an accelerated-wound closure.

CONCLUSIONS

This is the first report to describe the crucial role that alpha(2)AP plays following angiogenesis in the process of wound healing. Our results provide new insight into the role of alpha(2)AP on cutaneous wound healing.

A peptide isolated from alpha B-crystallin is a novel and potent inhibitor of platelet aggregation via dual prevention of PAR-1 and GPIb/V/IX

BACKGROUND

The ability of low-molecular-weight heat shock protein (HSP) to modulate thrombin-induced platelet aggregation has been investigated.

OBJECTIVES

We examined the inhibitory effects on platelet aggregation of nine amino acid sequences isolated from HSP20 or alpha B-crystallin and their various derivatives.

METHODS AND RESULTS

Platelet aggregation induced by various agonists was performed. These findings indicated that a peptide (Trp-Ile-Arg-Arg-Pro-Phe-Phe-Pro-Phe) from alpha B-crystallin significantly inhibits platelet aggregation induced by thrombin, TRAP (a protease activated receptor-1 agonist) and botrocetin, ristocetin (a stimulator of the platelet glycoprotein Ib/V/IX-von Willebrand factor axis), but not a protease-activated receptor-4 agonist, collagen and ADP. The inhibitory activity against thrombin or botrocetin is mainly linked to Arg-Arg-Pro-Phe or Trp-Ile-Arg-Arg-Pro, respectively, among nine amino acids. Additionally, during in vivo experiments, Trp-Ile-Arg-Arg-Pro-Phe-Phe-Pro-Phe shows a significant antithrombotic effect without marked bleeding.

CONCLUSION

Our results provide the basis for a potential new aspect of antiplatelet compound for the therapy of thrombosis and cardiovascular disease.

Inhibitory effects of an anti-rheumatic agent T-614 on immunoglobulin production by cultured B cells and rheumatoid synovial tissues engrafted into SCID mice

OBJECTIVE

To clarify the pharmacological action of an anti-rheumatic agent T-614, we investigated its effects on immunoglobulin (Ig) production by cultured B cells and Ig secretion from synovial tissues of patients with rheumatoid arthritis (RA) using SCID mice engrafted with human RA tissue (SCID-HuRAg).

METHODS

Murine B cells were prepared from mouse spleen by a T-cell depletion method. The cells were cultured with lipopolysaccharide (LPS) and/or interleukin 4 (IL-4) in the absence or presence of T-614. Human B cells were isolated from peripheral blood of healthy donors and the Ig production was induced by co-culture with autologous T cells and anti-CD3 antibody. SCID-HuRAg was prepared according to our previous method. T-614 was orally administered to the mice once daily for 4 weeks starting on the fourth week after the implantation. Then, peripheral blood was obtained and the implanted tissues were removed. Igs in the culture media or the sera were determined by enzyme-linked immunosorbent assay (ELISA).

RESULTS

In murine B-cell cultures, T-614 significantly decreased not only the IgM production stimulated with LPS but IgG1 production induced by LPS and IL-4. Regarding human B cells stimulated with T cells, it also inhibited IgM and IgG production. In SCID-HuRAg mice, high concentrations of polyclonal human IgG were detectable in the sera of all mice. A significant decrease in the IgG level was observed in the T-614-treated group compared with the control group.

CONCLUSIONS

We showed that T-614 inhibited Ig production by the cultured B cells and also decreased the high level of human IgG observed in SCID-HuRAg mice. These results may support its effect on plasma Ig in RA patients and provide insights into the mechanisms of its anti-rheumatic effect.

Kinetic analyses of ATP-dependent deoxyribonuclease (DNase) reactions on a quartz-crystal microbalance

We report here kinetic analyses of the hydrolysis of DNA by the ATP-dependent DNase using a DNA-immobilized quartz-crystal microbalance (QCM), which enables in situ real-time monitoring both the binding of enzyme and the hydrolysis reaction on DNA strands, as mass changes.

Alpha2-antiplasmin plays a significant role in acute pulmonary embolism

The importance of pulmonary embolism (PE) due to venous thrombosis is recognized in the treatment of vascular diseases. We have investigated the physiological effects of plasmin generation in experimental acute PE using mice deficient in plasminogen (Plg-/-) or alpha2-antiplasmin (alpha2-AP-/-). PE was induced by continuous induction of venous thrombus in the left jugular vein by endothelial injury due to photochemical reaction. The mortality of wild-type mice was 68.8% at 2 h after the initiation of venous thrombosis and it was significantly reduced in alpha2-AP-/- mice (41.7%). In contrast, Plg-/- mice did not survive. Histological evidence of thromboembolism in the lung was obtained in all mice. However, whereas a strict thromboembolism was observed in Plg-/- mice, only a few thrombi were detected in the lungs of alpha2-AP-/- mice. Plasma fibrinogen levels measured in mice were not different. When alpha2-AP was infused in alpha2-AP-/- mice, the mortality was indistinguishable from wild-type mice. Tissue-type plasminogen activator (tPA) did not reduce the mortality due to acute PE in wild-type mice. However, in alpha2-AP-/- mice, tPA (0.52 mg x kg-1) significantly decreased the mortality compared with that of alpha2-AP-/- mice without tPA. The bleeding time was not significantly prolonged in either type of mice treated with tPA. The lack of plasminogen increases the mortality due to acute PE while a lack of alpha2-AP decreases the mortality rate, which can be further reduced by tPA administration. Therefore, the combination of inhibition of alpha2-AP with thrombolytic therapy could be beneficial in the treatment of acute PE.

Corticosteroid treatment induces chondrocyte apoptosis in an experimental arthritis model and in chondrocyte cultures

OBJECT

In order to examine the mechanisms involved in steroid-induced arthropathy after intra-articular corticosteroid injection, a histological examination was performed in vivo using severe combined immunodeficiency (SCID) mice that were implanted with human articular cartilage into the back (SCID/hu model). In addition, the effect of corticosteroids on chondrocyte apoptosis was evaluated in vitro using cultured human chondrocytes.

METHOD

Human articular cartilage was obtained during knee surgery and implanted subcutaneously into the backs of SCID mice. One month later, weekly injections of corticosteroid (hydrocortisone acatate: 1 mg/0.2 ml, triamcinolone acetonide: 0.2 mg/0.2 ml, dexamethasone acetate: 0.1 mg/0.2 ml) in the subcutaneous cavity around the grafted cartilage in SCID mice were initiated. After six weeks of treatment, the grafted cartilage pieces were removed from the SCID mice and examined histologically. Chondrocyte apoptosis after corticosteroid treatment was also investigated using cultured human chondrocytes.

RESULT

In the corticosteroid treated, grafted articular cartilage, apoptotic chondrocytes were apparent in the superficial and middle layers of cartilage. But a reduced intensity of Safranin O staining was not remarkable. In the cultured chondrocytes, apoptotic changes were also observed after corticosteroid treatment.

CONCLUSION

Corticosteroid treatment induces chondrocyte apoptosis and it may be important to understand the steroid-induced arthropathy.

XML documentation of biopathways and their simulations in Genomic Object Net

Genomic Object Net is a software tool for modeling and simulating biopathways which employs the notion of hybrid functional net as its basic architechture. This paper shows how to integrate this basic architecture with XML documents for biopathway representations, simulations, and visualizations for creating a tailor-made simulation environment.

Contrasting effects of midazolam on induction of heat shock protein 27 by vasopressin and heat in aortic smooth muscle cells

We previously showed that vasopressin stimulates the induction of heat shock protein (HSP) 27, a low molecular-weight HSP, through protein kinase C activation in aortic smooth muscle A10 cells. In the present study, we examined the effects of midazolam, an intravenous anesthetic, on the HSP27 induction stimulated by vasopressin, heat, or sodium arsenite (arsenite) in A10 cells. Midazolam inhibited the accumulation of HSP27 induced by vasopressin or 12-O-tetradecanoylphorbol 13-acetate (TPA), a direct activator of protein kinase C. Midazolam also reduced the vasopressin-induced level of the mRNA for HSP27. In contrast, midazolam enhanced the HSP27-accumulation induced by heat or arsenite. Midazolam also enhanced the heat-increased level of the mRNA for HSP27. However, midazolam had no effect on the dissociation of the aggregated form of HSP27 following stimulation by vasopressin, heat, or arsenite. These results suggest that midazolam suppresses vasopressin-stimulated HSP27 induction in vascular smooth muscle cells, and that this inhibitory effect is exerted at a point downstream from protein kinase C. In contrast, midazolam enhanced heat- or arsenite-stimulated HSP27 induction. Thus, midazolam has dual effects on the HSP27 induction stimulated by various stresses in vascular smooth muscle cells.

The role of TNF-alpha in the pathogenesis of inflammation and joint destruction in rheumatoid arthritis (RA): a study using a human RA/SCID mouse chimera

OBJECTIVE

In order to elucidate which cytokine preferentially stimulates the synovium in patients with rheumatoid arthritis (RA), we investigated the roles of tumour necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6) using SCID mice engrafted with human RA tissue (SCID-HuRAg).

METHODS

The SCID-HuRAg mice were prepared according to our previously described method. First, SCID-HuRAg mice were treated with chimeric anti-TNF-alpha monoclonal antibody (mAb, 100 microg/mouse) and histological changes were examined 4 weeks after the initial treatment. Secondly, a total of 100 microg of recombinant TNF-alpha or IL-6 (0.6 microg/h) was administered daily to mice using an osmium pump. The histological changes and serum cytokine levels were examined 4 weeks after the initial administration. Human immunoglobulin G (IgG) was administered to mice as a control.

RESULTS

Synovial inflammatory cells were significantly decreased after the anti-TNF-alpha mAb treatment; conversely, the degree of synovial inflammation was significantly exacerbated by TNF-alpha administration. The levels of both IL-6 and TNF-alpha in sera were significantly increased by recombinant TNF-alpha administration, while TNF-alpha levels were unchanged by IL-6 administration. This suggests that TNF-alpha controls IL-6 production. Despite the profound changes in inflammation, we found no effects on bone and no articular cartilage damage was produced by TNF-alpha.

CONCLUSION

This study provides strong evidence that TNF-alpha is a key molecule in the control of the inflammatory changes that occur in the RA synovium. In addition, TNF-alpha regulates IL-6 production. However, other inflammatory pathways independent of TNF-alpha may contribute to the bone and cartilage damage seen in RA.

Mechanism of prostaglandin E2-stimulated heat shock protein 27 induction in osteoblast-like MC3T3-E1 cells

We investigated the effect of prostaglandin E2 (PGE2) on the induction of heat shock protein 27 (HSP27) and HSP70, and the mechanism behind the induction in osteoblast-like MC3T3-E1 cells. PGE2 time-dependently increased the level of HSP27 without affecting the level of HSP70. PGE2 stimulated the accumulation of HSP27 dose-dependently in the range between 10 nM and 10 microM. PGE2 stimulated the increase in the level of the mRNA for HSP27. Staurosporine and calphostin C, inhibitors of protein kinase C (PKC), suppressed the PGE2-induced HSP27 accumulation. The effect of PGE2 on HSP27 accumulation was reduced in the PKC down-regulated cells. BAPTA/AM, a chelator of intracellular Ca2+, or TMB-8, an inhibitor of intracellular Ca2+ mobilization, reduced the accumulation of HSP27 induced by PGE2. Dibutyryl cAMP had little effect on the basal level of HSP27. PGE2 induced the phosphorylation of both p44/p42 mitogen-activated protein (MAP) kinase and p38 MAP kinase. PD98059 and U-0126, inhibitors of the upstream kinase of p44/p42 MAP kinase, reduced the accumulation of HSP27 induced by PGE2. SB203580, a specific inhibitor of p38 MAP kinase, suppressed the HSP27 accumulation induced by PGE2. U-73122, an inhibitor of phospholipase C, and calphostin C reduced the PGE2-induced phosphorylation of both p44/p42 MAP kinase and p38 MAP kinase. These results indicate that PGE2 stimulates the induction of HSP27 through PKC-dependent activations of both p44/p42 MAP kinase and p38 MAP kinase in osteoblasts.

Intelligent system for topic survey in MEDLINE by keyword recommendation and learning text characteristics

We have implemented a system for assisting experts in selecting MEDLINE records for database construction purposes. This system has two specific features: The first is a learning mechanism which extracts characteristics in the abstracts of MEDLINE records of interest as patterns. These patterns reflect selection decisions by experts and are used for screening the records. The second is a keyword recommendation system which assists and supplements experts' knowledge in unexpected cases. Combined with a conventional keyword-based information retrieval system, this system may provide an efficient and comfortable environment for MEDLINE record selection by experts. Some computational experiments are provided to prove that this idea is useful.

The loss of susceptibility to apoptosis in exudated tissue neutrophils is associated with their nuclear factor-kappa B activation

Tissue neutrophils, human salivary neutrophils donated from healthy subjects and synovial fluid neutrophils collected from patients with rheumatoid arthritis were compared with circulating blood neutrophils. Concomitant treatment of circulating blood neutrophils with tumor necrosis factor-alpha (TNF-alpha) and cycloheximide induced neutrophil apoptosis, whereas the same treatment failed to induce significant apoptosis in salivary and synovial fluid neutrophils. Caspase-3 activation by TNF-alpha was observed in these tissue neutrophils, although its activity was significantly weaker than that in circulating blood neutrophils. In circulating blood neutrophils, TNF-alpha induced activation of nuclear factor-kappa B (NF-kappa B), whereas, in tissue neutrophils, NF-kappa B had been already activated without any stimulation, and no further activation was induced by the treatment with TNF-alpha. Furthermore, while pretreatment of neutrophils with an NF-kappa B inhibitor produced typical apoptotic changes in circulating blood neutrophils, this inhibitor did not produce any morphological apoptotic changes induced by TNF-alpha in tissue neutrophils. These results indicate that neutrophils undergo marked functional changes such as altered sensitivity to apoptosis-inducing stimuli in association with their exudation from blood into tissue, and that NF-kappa B activation is involved in the acquisition of resistance to TNF-alpha-induced apoptosis.

Inhibition by adenylyl cyclase-cAMP system of ET-1-induced HSP27 in osteoblasts

We have previously reported that endothelin-1 (ET-1) stimulates heat shock protein (HSP) 27 induction in osteoblast-like MC3T3-E1 cells and that p38 mitogen-activated protein (MAP) kinase acts at a point downstream from protein kinase C (PKC) in HSP27 induction. In the present study, we investigated the effect of the adenylyl cyclase-cAMP system on ET-1-stimulated induction of HSP27 in MC3T3-E1 cells. Dibutyryl-cAMP (DBcAMP) dose dependently inhibited the HSP27 accumulation stimulated by ET-1. Forskolin and cholera toxin significantly suppressed the ET-1-stimulated accumulation of HSP27. However, dideoxyforskolin, a forskolin derivative that does not activate cAMP, failed to suppress the ET-1-induced HSP27 accumulation. Forskolin reduced the p38 MAP kinase phosphorylation induced by ET-1 or 12-O-tetradecanoylphorbol-13-acetate (TPA). PGE(1), an extracellular agonist that activates cAMP production, reduced the ET-1-induced HSP27 accumulation. In addition, the phosphorylation of p38 MAP kinase induced by ET-1 or TPA was suppressed by PGE(1). Forskolin, DBcAMP, and PGE(1) suppressed the ET-1-stimulated increase in the mRNA level for HSP27. These results indicate that the adenylyl cyclase-cAMP system has an inhibitory role in ET-1-stimulated HSP27 induction in osteoblasts and that the effect is exerted at the point between PKC and p38 MAP kinase in osteoblasts.

Involvement of p38 MAP kinase in TGF-beta-stimulated VEGF synthesis in aortic smooth muscle cells

Although it is known that transforming growth factor (TGF)-beta induces vascular endothelial growth factor (VEGF) synthesis in vascular smooth muscle cells, the underlying mechanisms are still poorly understood. In the present study, we examined whether the mitogen-activated protein (MAP) kinase superfamily is involved in TGF-beta-stimulated VEGF synthesis in aortic smooth muscle A10 cells. TGF-beta stimulated the phosphorylation of p42/p44 MAP kinase and p38 MAP kinase, but not that of SAPK (stress-activated protein kinase)/JNK (c-Jun N-terminal kinase). The VEGF synthesis induced by TGF-beta was not affected by PD98059 or U0126, specific inhibitors of the upstream kinase that activates p42/p44 MAP kinase. We confirmed that PD98059 or U0126 did actually suppress the phosphorylation of p42/p44 MAP kinase by TGF-beta in our preparations. PD169316 and SB203580, specific inhibitors of p38 MAP kinase, significantly reduced the TGF-beta-stimulated synthesis of VEGF (each in a dose-dependent manner). PD169316 or SB203580 attenuated the TGF-beta-induced phosphorylation of p38 MAP kinase. These results strongly suggest that p38 MAP kinase plays a part in the pathway by which TGF-beta stimulates the synthesis of VEGF in aortic smooth muscle cells.

AlphaB-crystallin, a low-molecular-weight heat shock protein, acts as a regulator of platelet function

It has recently been reported that alphaB-crystallin, a low-molecular-weight heat shock protein, may be released from cells by mechanical stretch. We investigated a physiological role of alphaB-crystallin in platelet function. AlphaB-crystallin inhibited platelet aggregation induced by thrombin or botrocetin in hamsters and humans. These platelets had specific binding sites for alphaB-crystallin. Moreover, alphaB-crystallin significantly reduced thrombin-induced Ca2+ influx and phosphoinositide hydrolysis by phospholipase C in human platelets. Additionally, plasma levels of alphaB-crystallin were markedly elevated in cardiomyopathic hamsters. Levels of alphaB-crystallin in vessel walls after endothelial injury were markedly reduced. Therefore, our results suggest that alphaB-crystallin, which is discharged from vessel walls in response to endothelial injury, acts intercellularly as a regulator of platelet function.

Differential uptake of grepafloxacin by human circulating blood neutrophils and those exudated into tissues

The uptake of the antimicrobial quinolone agent, grepafloxacin, both by human circulating blood neutrophils and by those exudated into tissues, was evaluated in vitro by comparing the intracellular drug concentrations. In circulating blood neutrophils, the uptake of grepafloxacin was rapid and saturable at 37 degrees C. The uptake of grepafloxacin into circulating blood neutrophils was reduced by lowering the environmental temperature or by the presence of metabolic inhibitors, suggesting the involvement of an active transport mechanism. Furthermore, the uptake of grepafloxacin by tissue (salivary) neutrophils was also partially temperature-dependent and was significantly greater than that by circulating blood neutrophils, i.e. exudation of neutrophils into tissue results in a markedly enhanced transport mechanism for grepafloxacin. This phenomenon may be related to the higher defense activity against infection seen in exudated tissue neutrophils.

Activation of p44/p42 mitogen-activated protein kinase limits triiodothyronine-stimulated alkaline phosphatase activity in osteoblasts

It has been shown that thyroid hormone stimulates the activity of alkaline phosphatase, a marker of mature osteoblast phenotype, in osteoblasts. In the present study, we investigated whether p44/p42 mitogen-activated protein (MAP) kinase is involved in the thyroid hormone-stimulated alkaline phosphatase activity in osteoblast-like MC3T3-E1 cells. Triiodothyronine (T(3)) markedly induced the phosphorylation of p44/p42 MAP kinase. PD98059 and U0126, inhibitors of the upstream kinase that activates p44/p42 MAP kinase, significantly enhanced the T(3)-induced alkaline phosphatase activity in a dose-dependent manner. The phosphorylation of p44/p42 MAP kinase induced by T(3) was reduced by U0126. These results strongly suggest that p44/p42 MAP kinase takes part in the thyroid hormone-stimulated alkaline phosphatase activity in osteoblasts and that p44/p42 MAP kinase plays an inhibitory role in the thyroid hormone-effect.

Induction of a novel gelatinolytic activity in synovial tissue of patients with rheumatoid arthritis

Gelatinolytic activity induced by longtime incubation at 37 degrees C was found in extracts of rheumatoid synovial tissues. The enzyme activity was assessed by gelatin zymography and 3H-gelatin degradation assay. The observed enzyme had different characteristics from matrix metalloproteinases; it did not require metal ions for activity. However, metallocheltors blocked activation and addition of some metal ions restored the activation. The molecular size of the enzyme was changed time-dependently. The approximate molecular weight of the first enzyme produced by incubation was 65 kDa and it was converted to a broad size molecule with a molecular weight of 50 kDa after further incubation. Substrate specificity was detected for denatured collagen types I, II, III and IV.

Direct monitoring kinetic studies of DNA polymerase reactions on a DNA-immobilized quartz-crystal microbalance

Catalytic reactions of DNA polymerase I from E. coli (Klenow fragment, KF) were monitored directly with a template/primer (40/25- or 75/25-mer)-immobilized 27-MHz quartz-crystal microbalance (QCM). The 27-MHz QCM is a very sensitive mass-measuring device in aqueous solution, as the frequency decreases linearly with increasing mass on the QCM electrode at the nanogram level. Three steps in polymerase reactions which include 1) binding of DNA polymerase to the primer on the QCM (mass increase); 2) elongation of complementary nucleotides along the template (mass increase); and 3) release of the enzyme from the completely polymerized DNA (mass decrease), could be monitored continuously from the time dependencies of QCM frequency changes. The binding constant (Ka) of KF to the template/primer DNA was 10(8)M(-1) (k(on) = 10(5)M(-1)s(-1) and k(off)= 10(-3)s(-1)), and decreased to 10(6)M(-1) (k'on = 10(4)M(-1)s(-1) and k'off = 10(-2)s(-1)) for completely polymerized DNA. This is due to the 10-fold decrease in binding rate constant (k(on)) and 10-fold increase in dissociation rate constant (k(off)) for completed DNA strands. Ka values depended slightly on the template and primer sequences. The kinetic parameters in the elongation process (k(cat) and Km) depended only slightly on the DNA sequences. The repair process during the elongation catalyzed by KF could also be monitored in real time as QCM frequency changes.

Photochemically induced equilibrium dysfunction in the hamster model with evaluation by means of a new globe rotatory test system

Thrombosis in the inner ear is regarded as one of the causes of equilibrium dysfunction. We have established an experimental thrombosis model by producing a photochemical reaction between rose bengal and green light, and have evaluated the dysfunction with a new rotatory test system. Hamsters were treated with tissue-type plasminogen activator (tPA) in doses of 0, 0.13, 0.26, and 0.52 mg/kg. The equilibrium dysfunction of the hamsters was evaluated by scoring their behavior according to visual observation and by measuring their time on the rotatory test system. Treatment of animals with sufficient tPA (> or = 0.26 mg/kg) caused a significant amelioration of the behavior and a concomitant significant prolongation of time on the rotating globe. These findings suggest that the equilibrium dysfunction induced by the photochemical reaction was due to the thrombi formed, and that our test system may provide a useful tool for evaluating equilibrium dysfunction in hamsters.

Reconstituting telomerase activity using the telomerase catalytic subunit prevents the telomere shorting and replicative senescence in human osteoblasts

The rate of bone formation is largely determined by the number of osteoblasts, which in turn is determined by the rate of replication of progenitors and the life span of mature cells, reflecting the timing of death by apoptosis. However, the exact age-dependent changes of the cellular activity, replicative potential, and life span of osteoblasts have not been investigated to date. Here, we present evidence that the cellular activity, telomere lengths, and replicative life span of osteoblastic cells obtained from juxta-articular bone marrow gradually decrease with the advance of donor age. Recently, telomerase reverse transcriptase (hTERT) has been identified as a human telomerase catalytic subunit. We transfected the gene encoding hTERT into telomerase-negative human osteoblastic cells from donors and osteoblastic cell strain NHOst 54881 cells and showed that expression of hTERT induces telomerase activity in these osteoblastic cells. In contrast to telomerase-negative control cells, which exhibited telomere shortening and senescence after 10-15 population doublings, telomerase-expressing osteoblastic cells had elongated telomere lengths and showed continued alkaline phosphatase activity and procollagen I C-terminal propeptide (PICP) secretion for more than 30 population doublings. These results indicate that osteoblasts with forced expression of hTERT may be used in cell-based therapies such as ex vivo gene therapy, tissue engineering, and transplantation of osteoblasts to correct bone loss or osteopenia in age-related osteoporotic diseases.

Mechanism of prostaglandin D(2)-stimulated heat shock protein 27 induction in osteoblasts

We previously showed that prostaglandin D(2) (PGD(2)) stimulates activation of protein kinase C (PKC). We investigated whether PGD(2) stimulates the induction of heat shock protein (HSP) 27 and HSP70 in osteoblast-like MC3T3-E1 cells and the mechanism underlying the induction. PGD(2) increased the levels of HSP27 while having little effect on HSP70 levels. PGD(2) stimulated the accumulation of HSP27 dose dependently in the range between 10 nM and 10 microM. PGD(2) induced an increase in the levels of mRNA for HSP27. The PGD(2)-stimulated accumulation of HSP27 was reduced by staurosporine or calphostin C, inhibitors of PKC. PGD(2) induced the phosphorylation of p44/p42 mitogen-activated protein (MAP) kinase and p38 MAP kinase. The HSP27 accumulation induced by PGD(2) was significantly suppressed by PD98059, an inhibitor of the upstream kinase of p44/p42 MAP kinase, or SB203580, an inhibitor of p38 MAP kinase. Calphostin C suppressed the PGD(2)-induced phosphorylation of p44/p42 MAP kinase and p38 MAP kinase. PD98059 or SB203580 suppressed the PGD(2)-increased levels of mRNA for HSP27. These results strongly suggest that PGD(2) stimulates HSP27 induction through p44/p42 MAP kinase activation and p38 MAP kinase activation in osteoblasts and that PKC acts at a point upstream from both the MAP kinases.

Methotrexate inhibits rheumatoid synovitis by inducing apoptosis

OBJECTIVE

To clarify the pharmacological action of methotrexate (MTX) on the synovium of patients with rheumatoid arthritis (RA) using severe combined immunodeficient (SCID) mice in which human RA synovial tissue had been grafted (SCID-HuRAg).

METHODS

One month after engraftment of human RA tissue into SCID mice, MTX (0.3 mg/kg) was administered orally, then the appearance of apoptosis in the grafted tissue was examined by TdT mediated dUTP nick end labeling (TUNEL) staining and electron microscopy at various time points after MTX administration. In cultured synovial cells, synovial apoptotic changes after MTX treatment were studied by agarose gel electrophoresis and flow cytometric analysis. To compare the histological changes induced by MTX with those induced by other disease modifying antirheumatic drugs (DMARD) and a nonsteroidal antiinflammatory drug, histological examination of the grafted synovial tissues from SCID-HuRAg mice was conducted after 4 weeks of oral administration of MTX (0.3 mg/kg/week), salazosulfapyridine (30 mg/kg/day), auranofin (0.2 mg/kg/day), bucillamine (10 mg/kg/day), or indomethacin (2 mg/kg/day).

RESULTS

A significant decrease in the number of inflammatory cells was observed in the grafted synovial tissue of MTX treated SCID-HuRAg. A similar antiinflammatory effect was not observed with the other DMARD. Induction of apoptosis was noted with MTX treatment but not with the others. The pro-apoptotic effect of MTX was also observed in synovial cell cultures.

CONCLUSION

MTX induces apoptosis in RA synovium that, in turn, may contribute to its antiinflammatory effect on RA synovitis.

Involvement of p70 S6 kinase in bone morphogenetic protein signaling: vascular endothelial growth factor synthesis by bone morphogenetic protein-4 in osteoblasts

In the present study, we investigated the effect of bone morphogenetic protein (BMP)-4 on the synthesis of vascular endothelial growth factor (VEGF) in osteoblast-like MC3T3-E1 cells. BMP-4 significantly stimulated VEGF synthesis time-dependently up to 48 h. The stimulatory effect was dose-dependent in the range between 1 and 100 ng/ml. BMP-4 time-dependently phosphorylated p70 S6 kinase. Rapamycin, an inhibitor of p70 S6 kinase, suppressed the BMP-4-stimulated VEGF synthesis as well as the phosphorylation of p70 S6 kinase. The VEGF synthesis by BMP-4 was suppressed by wortmannin and LY294002, inhibitors of phosphatidylinositol 3-kinase. Both wortmannin and LY294002 inhibited the BMP-4-stimulated phosphorylation of p70 S6 kinase. BMP-4 did not affect the phosphorylation of Akt/protein kinase B. Taken together, our results strongly suggest that p70 S6 kinase takes part in BMP-4-stimulated VEGF synthesis as a positive regulator in osteoblasts and that phosphatidylinositol 3-kinase acts at a point upstream from p70 S6 kinase.

Involvement of p70 S6 kinase in bone morphogenetic protein signaling: vascular endothelial growth factor synthesis by bone morphogenetic protein-4 in osteoblasts

In the present study, we investigated the effect of bone morphogenetic protein (BMP)-4 on the synthesis of vascular endothelial growth factor (VEGF) in osteoblast-like MC3T3-E1 cells. BMP-4 significantly stimulated VEGF synthesis time-dependently up to 48 h. The stimulatory effect was dose-dependent in the range between 1 and 100 ng/ml. BMP-4 time-dependently phosphorylated p70 S6 kinase. Rapamycin, an inhibitor of p70 S6 kinase, suppressed the BMP-4-stimulated VEGF synthesis as well as the phosphorylation of p70 S6 kinase. The VEGF synthesis by BMP-4 was suppressed by wortmannin and LY294002, inhibitors of phosphatidylinositol 3-kinase. Both wortmannin and LY294002 inhibited the BMP-4-stimulated phosphorylation of p70 S6 kinase. BMP-4 did not affect the phosphorylation of Akt/protein kinase B. Taken together, our results strongly suggest that p70 S6 kinase takes part in BMP-4-stimulated VEGF synthesis as a positive regulator in osteoblasts and that phosphatidylinositol 3-kinase acts at a point upstream from p70 S6 kinase.

Proximal M2 false aneurysm after head trauma--Case report

A 72-year-old male presented with a post-traumatic false aneurysm of the right proximal M2 artery with massive subarachnoid hemorrhage after closed head injury. Serial computed tomography (CT) and angiography showed the development of the aneurysm which was verified at autopsy. He was admitted in a drowsy state just after a motorcycle accident. Initial brain CT showed subarachnoid hemorrhage without skull fracture. Follow-up brain CT showed a huge hematoma in the right temporal lobe. He died 47 hours after the accident. Histological examination of the aneurysm showed a false aneurysm. Delayed diagnosis of traumatic aneurysms leads to high mortality, so early surgical treatment is essential to save such patients.

Intra-articular injection of hyaluronate (SI-6601D) improves joint pain and synovial fluid prostaglandin E2 levels in rheumatoid arthritis: a multicenter clinical trial

OBJECTIVE

The relationship between clinicalfeatures and biochemical parameters of synovialfluid after serial intra-articular injections of sodium hyaluronate (SI-6601D) was investigated.

METHODS

SI-6601D (sodium hyaluronate with an average molecular weight of 8.4 x 10(5); 25mg/2.5ml/syringe) was injected intra-articularly into the knees of 25 patients with rheumatoid arthritis (RA) every week for 5 consecutive weeks. Clinical and biochemical parameters were monitored before and after injection. Clinicalfindings included pain, as a summation of 3 categories (pain at rest, pain in motion and pain in passive motion, each assessed on a 4-step rating scale), and inflammation, also as a summation of 3 categories (swelling, patellar ballotement and local warmth, each assessed on a 4-step rating scale). Pain on walking of patient was qualitatively assessed by visual analogue scale (VAS). The aspirated volume of synovialfluid (SFV) was recorded and levels of prostaglandin (PG) E2, transforming growth factor beta-1, tumor necrosis factor alpha, interleukin I receptor antagonist, chondroitin 4-sulfate (C4S) and chondroitin 6-sulfate were measured.

RESULTS

Significant improvement in pain symptoms (p < 0.0001), inflammation (p < 0.0001), VAS pain (p < 0.001) and SFV (p < 0.05) were observed after the 5 injections. Levels of PGE2 (p < 0.05) and C4S (p < 0.05) in the synovialfluid were significantly decreased.

DISCUSSION

SI-6601D improved local clinical symptoms in RA patients by suppressing PGE2 and, therefore, may be a useful treatment for local inflammation in RA.

Visualization and detectability of elements rarely contained in soft tissue by X-ray scanning analytical microscopy and electron-probe micro analysis

The detectability of elements rarely contained in soft tissue was compared using X-ray scanning analytical microscope (XSAM) and electron-probe micro analysis (EPMA). Mapping images of Ca, S and P in normal soft tissue of the rat and dissolved Ni in Ni implanted soft tissue could be obtained by XSAM and EPMA. EPMA was more sensitive in detection of P, while XSAM was superior for Ca, S and Ni mapping. The high detectability for heavier elements by XSAM was explained by the large volume of characteristic X-ray generation in XSAM and low attenuation of the characteristic X-rays from heavier elements. XSAM could provide clearer mapping images for heavier elements whose concentration was low without radiation damage to specimens.

Biocompatibility and osteogenesis of refractory metal implants, titanium, hafnium, niobium, tantalum and rhenium

To evaluate the biocompatibility of refractory metals, titanium, hafnium, niobium, tantalum and rhenium were implanted in rats, and histological observation and elemental mapping were performed by X-ray scanning analytical microscope (XSAM) and electron probe microanalyzer (EPMA). The titanium, hafnium, niobium, tantalum and rhenium wires were implanted in the subcutaneous tissue of the abdominal region and in femoral bone marrow of rats for either 2 or 4 weeks. No inflammatory response was observed around the implants, and all the implants were encapsulated with thin fibrous connective tissue. No dissolution of these metals was detected by XSAM in the soft tissue. Histological examination of the hard tissue showed that the amount of new bone formation decreased slightly from the second to the fourth week after implantation, and that the percentage of bone in contact with the implant increased markedly over the same period. No dissolution of these metals was detected by EPMA in the hard tissue. The Ca and P intensities in the mapping images of newly formed bone were higher after 4 weeks than those after 2 weeks, which suggests that the newly formed bone continued to mature from 2 to 4 weeks after implantation. These results indicate that titanium, hafnium, niobium, tantalum and rhenium have good biocompatibility and osteoconductivity.

Stimulatory effect of basic fibroblast growth factor on induction of heat shock protein 27 in osteoblasts: role of protein kinase C

In a previous study we showed that basic fibroblast growth factor (bFGF) stimulates activation of protein kinase C through phosphoinositide hydrolysis by phospholipase C and phosphatidylcholine hydrolysis by phospholipase D in osteoblast-like MC3T3-E1 cells. In the present study, we investigated whether bFGF stimulates the induction of heat shock protein (HSP) 27, a low-molecular-weight HSP, and HSP70, a high-molecular-weight HSP, in MC3T3-E1 cells and the mechanism behind the induction. bFGF increased the level of HSP27 while having little effect on HSP70 level. bFGF stimulated the accumulation of HSP27 dose-dependently in the range between 1 and 30 ng/ml. bFGF induced an increase in the level of the mRNA for HSP27. The bFGF-stimulated accumulation of HSP27 was reduced by inhibitors of protein kinase C. The bFGF-induced HSP27 accumulation was reduced in protein kinase C-downregulated MC3T3-E1 cells. U-73122, an inhibitor of phospholipase C, and propranolol, a phosphatidic acid phosphohydrolase inhibitor, suppressed the bFGF-stimulated HSP27 accumulation. These results strongly suggest that bFGF stimulates HSP27 induction through protein kinase C activation in osteoblasts.

Characterization of simple and reproducible vascular stenosis model in hypercholesterolemic hamsters

The importance of low-density lipoprotein (LDL) in the etiology of atherosclerosis is well recognized. We have established a reproducible stenosis model in hypercholesterolemic hamsters, and the process of arterial stenosis by thrombus or neointima was studied and compared with that in normal hamsters. The level of plasma LDL was 4.6 times higher in hamsters fed a high-cholesterol diet than in hamsters fed normal food. Endothelial injury in right common carotid arteries was induced using a modified catheter. Arterial blood flow was monitored continuously using a Doppler flow probe. Arterial patency after the initiation of injury in high-cholesterol hamsters was significantly changed as compared with that of normal hamsters. Neointima was observed 2 wk after the vascular injury. The neointimal area of high-cholesterol hamsters was significantly larger than that of normal hamsters. To characterize the stenosis in hypercholesterolemic hamsters, we measured platelet aggregation, thrombin time, activated partial thromboplastin time, and proliferating smooth muscle cells (SMC) in vitro and in vivo. The half-maximal inhibitory concentration value for platelet aggregation induced by thrombin or collagen, the DNA synthesis stimulated by platelet-derived growth factor (PDGF)-BB, and 5-bromo-2-deoxy-uridine labeling indices (proliferating index of SMC in vivo) in high-cholesterol hamsters were each significantly higher than the comparable value from normal hamsters. However, specific binding of PDGF-BB in SMC was not different between the two types of hamsters. Furthermore, we investigated the inhibitory effects of probucol or losartan on neointima formation using this model. Probucol, but not losartan, significantly reduced the neointimal area in hypercholesterolemic hamsters. These findings indicated that high levels of plasma LDL strongly contributed to the development of thrombus and neointima formation via both up-regulation of platelet aggregation and the enhancement of SMC proliferation. This stenosis model may be useful for the investigation of hypercholesterolemia-associated cardiovascular diseases.

[Relationship between periarticular osteoporosis and osteoblast senescence in patients with rheumatoid arthritis]

The rate of bone formation is largely determined by the number of osteoblasts, which in turn is determined by the rate of replication of progenitors and the life-span of mature cells, reflecting the timing of death by apoptosis. However, the exact age-dependent changes of the cellular activity, replicative potential and life-span of osteoblasts have not so far been investigated to date. Here we present evidence that the cellular activity, telomere lengths and replicative life-span of osteoblastic cells obtained from juxta-articular bone marrow gradually decrease with the advance of donor age in patients with rheumatoid arthritis or osteoarthritis. Recently, human telomerase reverse transcriptase (hTERT) has been identified as a human teromerase catalytic subunit. We postulate that an expansion of the life-span of osteoblasts and their maintenance as differentiated bone matrix-producing cells may allow for autologus or allogenic cell and gene therapy in bone and joint diseases including osteoporosis. We therefore transfected human osteoblasts with a vector expressing hTERT cDNA, and investigated whether the replicative life-span can be expanded by the introduction of telomerase in human osteoblasts.