Isolation and diversity of actinomycetes in the chesapeake bay

Chesapeake Bay was investigated as a source of actinomycetes to screen for production of novel bioactive compounds. The presence of relatively large populations of actinoplanetes (chemotype II/D actinomycetes) in Chesapeake Bay sediment samples indicates that it is an eminently suitable ecosystem from which to isolate actinomycetes for screening programs. Actinomycetes were isolated from sediment samples collected in Chesapeake Bay with an isolation medium containing nalidixic acid, which proved to be more effective than heat pretreatment of samples. Actinomycete counts ranged from a high of 1.4 x 10 to a low of 1.8 x 10 CFU/ml of sediment. Actinomycetes constituted 0.15 to 8.63% of the culturable microbial community. The majority of isolates from the eight stations studied were actinoplanetes (i.e., chemotype II/D), and 249 of these isolates were obtained in a total of 298 actinomycete isolates. Antimicrobial activity profiles indicated that diverse populations of actinoplanetes were present at each station. DNA hybridization studies showed considerable diversity among isolates between stations, but indicated that actinoplanete strains making up populations at nearby stations were more similar to each other than to populations sampled at distant stations. The diversity of actinoplanetes and the ease with which these organisms were isolated from Chesapeake Bay sediments make this a useful source of these actinomycetes.

ITZ-1, a client-selective Hsp90 inhibitor, efficiently induces heat shock factor 1 activation

ITZ-1 is a chondroprotective agent that inhibits interleukin-1beta-induced matrix metalloproteinase-13 (MMP-13) production and suppresses nitric oxide-induced chondrocyte death. Here we describe its mechanisms of action. Heat shock protein 90 (Hsp90) was identified as a specific ITZ-1-binding protein. Almost all known Hsp90 inhibitors have been reported to bind to the Hsp90 N-terminal ATP-binding site and to simultaneously induce degradation and activation of its multiple client proteins. However, within the Hsp90 client proteins, ITZ-1 strongly induces heat shock factor-1 (HSF1) activation and causes mild Raf-1 degradation, but scarcely induces degradation of a broad range of Hsp90 client proteins by binding to the Hsp90 C terminus. These results may explain ITZ-1's inhibition of MMP-13 production, its cytoprotective effect, and its lower cytotoxicity. These results suggest that ITZ-1 is a client-selective Hsp90 inhibitor.

2-{3-[4-(Alkylsulfinyl)phenyl]-1-benzofuran-5-yl}-5-methyl-1,3,4-oxadiazole derivatives as novel inhibitors of glycogen synthase kinase-3beta with good brain permeability

Glycogen synthase kinase 3beta (GSK-3beta) inhibition is expected to be a promising therapeutic approach for treating Alzheimer's disease. Previously we reported a series of 1,3,4-oxadiazole derivatives as potent and highly selective GSK-3beta inhibitors, however, the representative compounds 1a,b showed poor pharmacokinetic profiles. Efforts were made to address this issue by reducing molecular weight and lipophilicity, leading to the identification of oxadiazole derivatives containing a sulfinyl group, (S)-9b and (S)-9c. These compounds exhibited not only highly selective and potent inhibitory activity against GSK-3beta but also showed good pharmacokinetic profiles including favorable BBB penetration. In addition, (S)-9b and (S)-9c given orally to mice significantly inhibited cold water stress-induced tau hyperphosphorylation in mouse brain.

The chondroprotective agent ITZ-1 inhibits interleukin-1beta-induced matrix metalloproteinase-13 production and suppresses nitric oxide-induced chondrocyte death

In a screening program aimed at discovering anti-osteoarthritis (OA) drugs, we identified an imidazo[5,1-c][1,4]thiazine derivative, ITZ-1, that suppressed both interleukin-1beta (IL-1beta)-induced proteoglycan and collagen release from bovine nasal cartilage in vitro and suppressed intra-articular infusion of IL-1beta-induced cartilage proteoglycan degradation in rat knee joints. ITZ-1 did not inhibit enzyme activities of various matrix metalloproteinases (MMPs), which have pivotal roles in cartilage degradation, while it selectively inhibited IL-1beta-induced production of MMP-13 in human articular chondrocytes (HAC). IL-1beta-induced MMP production has been shown to be mediated by extracellular signal-regulated protein kinase (ERK), p38 kinase, and c-Jun N-terminal kinase (JNK) of the mitogen-activated protein kinase (MAPK) family signal transduction molecules. An ERK-MAPK pathway inhibitor (U0126), but not a p38 kinase inhibitor (SB203580) or a JNK inhibitor (SP600125), also selectively inhibited IL-1beta-induced MMP-13 production in HAC. Furthermore, ITZ-1 selectively inhibited IL-1beta-induced ERK activation without affecting p38 kinase and JNK activation, which may account for its selective inhibition of MMP-13 production. Inhibition of nitric oxide (NO)-induced chondrocyte apoptosis has been another area of interest as a therapeutic strategy for OA, and ITZ-1 also suppressed NO-induced death in HAC. These results suggest that ITZ-1 is a promising lead compound for a disease modifying anti-OA drug program.

Spectroscopic evidence for competing reconstructions in polar multilayers LaAlO3/LaVO3/LaAlO3

We have studied the valence redistribution of V in LaAlO(3)/LaVO(3)/LaAlO(3) trilayers, which are composed of only polar layers grown on SrTiO3 (001) substrates, by core-level photoemission spectroscopy. We have found that the V valence is intermediate between V3+ and V4+ for thin LaAlO3 cap layers, decreases with increasing cap-layer thickness, and finally recovers the bulk value of V3+ at approximately 10 unit-cell thickness. In order to interpret these results, we propose that the atomic reconstruction of the polar LaAlO3 surface competes with the purely electronic V valence change so that the polar catastrophe is avoided at the cost of minimum energy.

Hyaluronan inhibits expression of ADAMTS4 (aggrecanase-1) in human osteoarthritic chondrocytes

Background:

Intra-articular injection of hyaluronan (HA) has been suggested to have a disease-modifying effect in osteoarthritis, but little is known about the possible mechanisms.

Objective:

To investigate the effects of HA species of different molecular mass, including 800 kDa (HA800) and 2700 kDa (HA2700), on the expression of aggrecanases (ie, ADAMTS species), which play a key role in aggrecan degradation.

Methods:

The effects of HA species on the expression of ADAMTS1, 4, 5, 8, 9 and 15 in interleukin 1α (IL1α)-stimulated osteoarthritic chondrocytes were studied by reverse transcription PCR and real-time PCR. Expression of ADAMTS4 protein and aggrecanase activity and signal transduction pathways of IL1, CD44 and intracellular adhesion molecule 1 (ICAM1) were examined by immunoblotting.

Results:

IL1α treatment of chondrocytes induced ADAMTS4, and HA800 and HA2700 significantly decreased IL1α-induced expression of ADAMTS4 mRNA and protein. IL1α-stimulated aggrecanase activity in osteoarthritic chondrocytes was reduced by treatment with HA2700 or transfection of small interfering RNA for ADAMTS4. A similar result was obtained when HA2700 was added to explant cultures of osteoarthritic cartilage. HA2700 neither directly inhibited nor bound to ADAMTS4. Downregulation of ADAMTS4 expression by HA2700 was attenuated by treatment of IL1α-treated chondrocytes with antibodies to CD44 and/or ICAM1. The increased phosphorylation of IL1 receptor-associated kinase-1 and extracellular signal-regulated protein kinase1/2 induced by the IL1α treatment was downregulated by enhanced IRAK-M expression after HA2700 treatment.

Conclusion:

These data suggest that HA2700 suppresses aggrecan degradation by downregulating IL1α-induced ADAMTS4 expression through the CD44 and ICAM1 signalling pathways in osteoarthritic chondrocytes.

Photoemission from buried interfaces in SrTiO3/LaTiO3 superlattices

We have measured photoemission spectra of SrTiO3/LaTiO3 superlattices with a topmost SrTiO3 layer of variable thickness. A finite coherent spectral weight with a clear Fermi cutoff was observed at chemically abrupt SrTiO3/LaTiO3 interfaces, indicating that an "electronic reconstruction" occurs at the interface between the Mott insulator LaTiO3 and the band insulator SrTiO3. For SrTiO3/LaTiO3 interfaces annealed at high temperatures (approximately 1000 degrees C), which leads to Sr/La atomic interdiffusion and hence to the formation of La(1-x)Sr(x)TiO3-like material, the intensity of the incoherent part was found to be dramatically reduced whereas the coherent part with a sharp Fermi cutoff was enhanced due to the spread of charge. These important experimental features are well reproduced by layer dynamical-mean-field-theory calculation.

Transient elevation of intracellular calcium ion levels as an early event in T-2 toxin-induced apoptosis in human promyelotic cell line HL-60

Recently we have reported that T-2 toxin, a trichothecene mycotoxin produced by Fusarium species, is a potent inducer of apoptosis in the human promyelotic cell line HL-60. To clarify the signal transduction pathway of apoptosis primed by T-2 toxin, T-2 toxin-induced apoptosis was investigated in detail using confocal laser microscopy and flow cytometry. Apoptosis in HL-60 cells induced by T-2 toxin was dose dependent when the cells were treated with concentrations of 5-100 ng/ml for more than 2 hr. The apoptosis proceeds through various cell cycle stages of HL-60 cells. Prior to apoptosis, the intracellular calcium ion (Ca+2i) level was markedly elevated within 3-5 min after exposure to T-2 toxin and returned to normal level thereafter. A well-known chelator for Ca+2i, ethylene-N,N,N', N'-tetraacetic acid 4K acetoxymethyl ester (BAPTA-AM), a Ca+2-dependent endonuclease inhibitor ZnCl2, and calpain inhibitor 1 sharply blocked T-2 toxin-induced apoptosis. These results strongly suggest that the Ca+2 signal triggered by T-2 toxin is transduced by the activation of endonuclease and protease, and ultimately evokes apoptosis.

Trial of Remote Telemedicine Support for Patients with Chronic Respiratory Failure at Home through a Multistation Communication System

To create and test a multistation telemedicine support system, three remote locations were connected: the homes of two patients with chronic respiratory failure, the hospital of the attending physician, and the hospital of the pulmonary specialist. Real-time connections were set up between the three locations. Medical history and biologic variables were noninvasively recorded, including blood pressure, arterial oxygen saturation, three-lead electrocardiogram, and end-tidal carbon dioxide. Both physicians shared in these data real-time. If necessary, the respiratory specialist could provide medical advice to the attending physician based on the patient's condition. The trial program resulted in the same information being exchanged remotely using the multi-station telemedicine system that would be exchanged in a direct, face-to-face encounter. This result, together with the improvement in quality of life and the establishment of appropriate treatment and cooperation between the respiratory specialist and attending physician, suggests our system can be considered useful and promising for further use.

[Completion pneumonectomy after 4 times of resections for metastatic lung tumors from rectal carcinoma]

We report a case of completion pneumonectomy after 4 times of metastasectomy for metastatic lung tumors from rectal carcinoma. A 63-year-old man underwent Miles' operation for advanced rectal carcinoma. Forty-seven months after the operation, bilateral metastasis was appeared, and bilateral metastasectomy was performed. After the resection, 3 times of metastasectomy were performed during 40 months. Follow-up X-ray and computed tomography (CT) showed abnormal shadow in his left hilum of lung. Completion pneumonectomy with mediastinal lymph node sampling was performed. He is still alive without recurrence 4 years after first thoracotomy. Repeated pulmonary resection can lead to good outcome for selective patients with metastatic colorectal carcinoma, and repeated surgery can be useful for pulmonary recurrences after thoracotomy.

[Left superior segmental resection for lung cancer with anomalous branching of the left A4 + 5; report of 2 cases]

We experienced with two cases of left superior segmental resection for lung cancer with the left A4 + 5 which arose from pars mediastinalis. Left superior segmental resection was performed on a 67-year-old female and an 81-year-old male. In both cases we divided A4 + 5 temporarily and anastomosed to pars interlobaris of the left pulmonary artery. As a result, it was able to perform safe division of bronchus. In cases with A4 + 5 arising from pars mediastinalis, operation is difficult and risky because A4 + 5 locates in front of the left upper lobe bronchus. It is safer to reconstruct A4 + 5 on pars interlobaris of the left pulmonary artery in such cases.

[Catamenial pneumothorax in a young patient diagnosed by thoracoscopic surgery; report of a case]

A 16-year-old woman presented with chest pain on 2 days before the onset of menstruation and was referred to our hospital because of a pneumothorax. She was diagnosed as spontaneous penumothorax and surgical treatment was performed. Thoracoscopy revealed the presence of multiple blueberry spots near central tendon of the diaphragm and little pleural effusion. No other abnormal lesions were found in the left pleural cavity and left lung. Thoracoscopic biopsy and coagulation of the lesions were successfully performed. Histological findings of biopsied specimen did not contradict as an endometoriosis and catamenial pneumothorax was diagnosed. CA 125 level of the pleural effusion had increased to 99.2 U/ml. Because she was young, she did not receive a systemic hormonal therapy.

Antinociceptive effects of N-acyloctahydropyrido[3,2,1-ij][1,6]naphthyridine in mice: structure-activity relation study of matrine-type alkaloids part II

N-Acyloctahydropyrido[3,2,1-ij][1,6]naphthyridines were synthesized as derivatives of matrine-type alkaloids, and the structure-activity relations were examined by the acetic acid-induced abdominal contraction test. The antinociceptive potencies of N-acyloctahydropyrido[3,2,1-ij][1,6]naphthyridines were significantly lower than those of (+)-matrine. The antinociceptive effects of N-benzyloctahydropyrido[3,2,1-ij][1,6]naphthyridines are approximately 5.6 to 6.5 times less than those of N-benzoyloctahydropyrido[3,2,1-ij][1,6]naphthyridine. These findings suggest that the amide group of matrine-type alkaloids is an essential functional group that influences antinociceptive potency. The antinociceptive effect of 4c was markedly antagonized by pretreatment with Naloxone, and that of 3c partially so.

Effect of HEMA on bonding of Er:YAG laser-irradiated bovine dentine and 4-META/MMA-TBB resin

The purpose of this study was to evaluate the priming effect of 2-hydroxyethylmetaclirate (HEMA) following acid treatment on resin bonding to prototype Er:YAG laser-irradiated dentine. Extracted bovine dentine following laser irradiation was acid treated by aqueous solution of 10% citric acid (10-0) or 10% citric acid/3% ferric chloride (10-3), and additionally treated with 35% HEMA. Pre-treated dentines were bonded to the polymethyl-methacrylate (PMMA) rod with 4-META/MMA-TBB resin (Super Bond C & B) and miniaturized dumbbell-shaped bonded specimens were prepared. These specimens profiled for tensile bond testing and fractured surfaces were observed by scanning electron microscopy (SEM). Cross-sections of resin-dentine interface were also examined. The HEMA treatment following acid conditioned by 10-3 or 10-0 for both laser-irradiated and non-irradiated dentines was significantly higher than that without HEMA treatment. SEM view of a fractured specimen showed some cohesive failure in cured resin, but almost all of the fractured surface shows boundary failure between the penetrated resin and underlying dentine. A cross-sectional view of the interface showed a very thick hybrid layer between the hybridized dentine and underlying dentine. It was concluded that HEMA treatment following acid conditioning provided a slightly higher bond strength for both the Er:YAG laser-irradiated and non-irradiated dentines. However, the bond strength of Er:YAG laser irradiated dentine was significantly lower than that of the non-irradiated dentine.

Survey and analysis of satellite-based telemedicine projects involving Japan and developing nations: investigation of transmission rates, channel numbers, and node numbers

We surveyed interactive telemedicine projects via telecommunications satellite (AMINE-PARTNERS, Post-PARTNERS, and Shinshu University Project using Inmarsat satellites) offered by Japan as assistance to developing countries. The survey helped clarify channel occupation time and data transfer rates. Using our survey results, we proposed an optimized satellite model with VSATs simulating the number of required channels and bandwidth magnitude. For future implementation of VSATs for medical use in developing nations, design of telecommunication channels should take into consideration TCP/IP-based operations. We calculated that one hub station with 30-76 VSATs in developing nation can be operated on bandwidth 6 Mbps using with 128 Kbps videoconferencing system for teleconsultation and teleconference, and linking with Internet.

Suppressive mechanisms of EPA on human T cell proliferation

In vivo and in vitro experiments show that polyunsaturated fatty acids (PUFAs) including eicosapentaenoic acid (EPA) inhibit mitogen- or antigen-stimulated proliferation of T cells in rodents and humans. However, the exact manner and mechanisms by which PUFA inhibits T cell proliferation is not clear. In the present study, we investigated the suppressive effects of EPA, an n-3 PUFA, on PHA stimulated human peripheral blood T cells. Our results showed that EPA suppresses mitogen- or antigen-stimulated human T cell proliferation by at least 2 steps; step 1) EPA suppresses T cell proliferation by inhibiting IL-2R alpha expression and IL-2 production; step 2) EPA induces cell death of blast T cells without reducing the expression of IL-2R alpha. We also showed that EPA selectively stimulates the cell death of blast T cells but not resting T cells. The suppressive effect of EPA was mediated via the production of reactive oxygen products, because EPA-stimulated H2O2 production and the suppressive effect of EPA was restored by addition of catalase or NAC. These results taken together suggest that such immunosuppressive effects of EPA may explain the apparent benefits of EPA-enriched diets for patients with inflammatory disorders.

Increases in plasma ACTH and cortisol after hypertonic saline infusion in patients with central diabetes insipidus

To clarify the mechanism for the potentiation of CRH-induced ACTH response by the infusion of hypertonic saline, we investigated changes in plasma ACTH concentration after infusion of 5% hypertonic saline in five patients with untreated central diabetes insipidus (DI). Basal levels of plasma ACTH and cortisol in the DI group were not significantly different from those in normal control subjects. The infusion of hypertonic saline produced an increase in plasma arginine vasopressin (AVP) in controls, but did not elevate ACTH. However, in patients with DI, the plasma AVP concentration did not change, but circulating ACTH increased 3.6-fold (7.7 +/- 1.5 to 23.0 +/- 2.7 pmol/liter; P < 0.01), and plasma cortisol also increased significantly (298 +/- 99 to 538 +/- 124 nmol/liter; P < 0.05). Moreover, a positive correlation was observed between plasma ACTH and osmolality (r = 0.72; P < 0.005). These results indicate that ACTH secretion in DI patients is regulated by a mechanism distinct from that in healthy subjects. It seems possible that the increase in plasma osmolality promotes ACTH secretion in DI patients through AVP and/or urocortin via the hypophyseal portal system, independent of the AVP secretion from magnocellular neurons.

Effect of cytokines on growth and differentiation of leukaemic cells with translocation t(6;9)(p23;q34)

The translocation t(6;9)(p23;q34) is detected infrequently in subtypes of haematological malignancies including acute myelogenous leukaemia (AML) and myelodysplastic syndrome (MDS). Although the t(6;9) leukaemia is commonly associated with bone marrow basophilia, the cytological characteristics of leukaemic cells are unclear. In the current study, we examined the in vitro effects of several cytokines on growth and differentiation of t(6;9) leukaemic cells. Isolated bone marrow mononuclear cells from four patients with t(6;9) (two MDS and two AML) were cultured for 14 d in the presence or absence of each cytokine. At the end of culture, viable cells were counted, and their histology was examined. Bone marrow cells obtained from 22 patients (10 AML, six AML from MDS, six MDS) lacking t(6;9) were used as controls. Compared with control cultures, significantly higher numbers of blasts appeared in the culture of bone marrow cells from t(6;9)-positive patients in response to stimulation with granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage CSF (GM-CSF) or interleukin 3 (IL-3). Stem cell factor (SCF) had little effect. Neutrophil counts were also significantly increased in the presence of G-CSF or IL-3. SCF and IL-3 were potent in increasing basophil counts from t(6;9)-positive cultures. These findings suggest that bone marrow cells obtained from t(6;9) patients are highly sensitive to growth- and/or differentiation-promoting cytokines. Special attention should be paid to the use of "therapeutic" cytokines in these patients.

Inhibition of BMP2-induced, TAK1 kinase-mediated neurite outgrowth by Smad6 and Smad7

BACKGROUND

BMP2 is known to play a wide variety of roles, including some in the development of the nervous system. This cytokine has been reported to induce neurite outgrowth in rat pheochromocytoma PC12 cells via the activation of a p38 MAP kinase, although its regulatory mechanism remains largely to be elucidated.

RESULTS

BMP2-induced neurite outgrowth in PC12 cells was inhibited by the introduction of a kinase-negative form of a MAP kinase kinase kinase, TAK1, an upstream regulatory kinase for p38 kinase. Following BMP2 stimulation, the expression of Smad6 and Smad7, inhibitory Smad species that are known to inhibit the BMP2-restricted Smad species, Smad1, Smad5 and Smad8, was up-regulated. Unexpectedly, over-expression of either Smad6 or Smad7 in PC12 cells repressed the BMP2-induced neurite outgrowth and severely impeded the p38 kinase pathway. Both of these inhibitory Smads were found to interact physically with TAK1-binding protein, a molecule required for TAK1 activation.

CONCLUSIONS

This study demonstrates that BMP2-induced neurite outgrowth in PC12 cells involves activation of the TAK1-p38 kinase pathway which is inhibited by Smad6 and Smad7.