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1.
J Nanosci Nanotechnol ; 20(5): 2979-2986, 2020 May 01.
Article in English | MEDLINE | ID: mdl-31635636

ABSTRACT

InGaN epitaxial layers were grown on c-plane sapphire substrates using the metalorganic vapour phase epitaxy (MOVPE) system at 760 °C. By varying the total flow rate of group-III sources (TMI+TEG) with a fixed molar ratio of group-III sources [TMI/(TMI+TEG)], the influence of V/III ratio were investigated from 4500 to 20000. The grown N-polar InGaN layers were investigated by atomic force microscopy and it is found that the surface roughness decreases with increasing the V/III ratios. High resolution X-ray diffraction analyses show that the phase separation decreases with increasing the V/III ratios. Photoluminescence measurements reveal that the peak position of the band-edge emission shifted toward the shorter wavelength with increasing the V/III ratios. Reciprocal space mapping (RSM) analyses were carried out on InGaN films. At low V/III ratio, the phase separation can be detected in InGaN films.

2.
J Eur Acad Dermatol Venereol ; 32(4): 606-614, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29034518

ABSTRACT

BACKGROUND: Appropriate goal-oriented treatment strategies are important for optimal treatment outcomes and may prevent under-treatment. As treatment goals vary by patient, a study to examine treatment goals is more meaningful when patients and their physicians are paired. There has not been any study that examines alignment between paired psoriasis patients and physicians in real-world clinical practice using skin clearance as a treatment goal indicator. OBJECTIVES: To evaluate treatment goal alignment between psoriasis patients and their paired physicians, and to quantitatively identify factors associated with goal misalignment. METHODS: The study was a nationwide multicenter cross-sectional observational study. Subjects were physician-reported moderate-to-severe psoriasis patients with a history of systemic treatments, directly paired with their treating physicians. Subjects completed surveys independently. Treatment goals included seven categories, and patient-physician pairs were grouped as 'aligned' or 'misaligned' when the answers were the same or different, respectively. RESULTS: A total of 425 pairs (mean response rate, 94.7%) of responses were collected from 54 sites (64.8% general practitioners or clinics; 35.2% university or large hospitals). Treatment goal misalignment was found in 67.9% of the patient-physician pairs. The misalignment was mainly 'patient predominant' (60.9%) indicating that patients had higher goals ('complete clearance') than physicians. In the multivariate logistic regression analyses, patients' treatment expectation for 'complete clearance' [odds ratio (OR): 1.927; 95% confidential interval (CI): 1.232-3.016] and physician rating of 'level of understanding on treatment options' being low (OR: 1.552, 95% CI; 1.082-2.227) were significant factors for treatment goal misalignment. CONCLUSIONS: The majority of treatment goal misalignment was found between paired psoriasis patients and their treating physicians in Japan. The most important contributing factors to misalignment were patients' treatment expectation for 'complete clearance' and physicians' rating of their patients' 'level of understanding on treatment options' being low.


Subject(s)
Goals , Patient Participation , Physician-Patient Relations , Psoriasis/therapy , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Humans , Japan , Male , Middle Aged , Psoriasis/enzymology
3.
J Nanosci Nanotechnol ; 14(8): 6112-5, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25936067

ABSTRACT

In-composition of N-polar InGaN films on the sapphire substrate with the surface nitridation was investigated. By varying the ratio of the group-III source flow rate from 0.7 to 0.95, the In-composition and the surface morphologies of InGaN films were changed. The In-composition of N-polar InGaN films was affected by the strain relaxation and the surface morphologies.

4.
Acta Neurol Scand Suppl ; (197): 19-24, 2013.
Article in English | MEDLINE | ID: mdl-23480152

ABSTRACT

Perampanel [2-(2-oxo-1-phenyl-5-pyridin-2-yl-1,2-dihydropyridin-3-yl)benzonitrile; E2007] is a potent, selective, orally active non-competitive AMPA receptor antagonist developed for the treatment of epilepsy. Perampanel has a 2,3'-bipyridin-6'-one core structure, distinguishing it chemically from other AMPA receptor antagonist classes. Studies in various physiological systems indicate that perampanel selectively inhibits AMPA receptor-mediated synaptic excitation without affecting NMDA receptor responses. Blocking of AMPA receptors occurs at an allosteric site that is distinct from the glutamate recognition site. Radioligand-binding studies suggest that the blocking site coincides with that of the non-competitive antagonist GYKI 52466, believed to be on linker peptide segments of AMPA receptor subunits that transduce agonist binding into channel opening. As is typical for AMPA receptor antagonists, perampanel exhibits broad-spectrum antiseizure activity in diverse animal seizure models. Perampanel has high oral bioavailability, dose-proportional kinetics, and undergoes oxidative metabolism, primarily via CYP3A4, followed by glucuronidation. The terminal half-life (t½ ) in humans is 105 h; however, in the presence of a strong CYP3A4 inducer (such as carbamazepine), the t½ can be reduced. In sum, perampanel is a selective, centrally acting, negative allosteric modulator of AMPA receptors with good oral bioavailability and favorable pharmacokinetic properties.


Subject(s)
Drug Evaluation, Preclinical , Epilepsy/drug therapy , Excitatory Amino Acid Antagonists/therapeutic use , Pyridones/therapeutic use , Animals , Disease Models, Animal , Excitatory Amino Acid Antagonists/chemistry , Excitatory Amino Acid Antagonists/pharmacology , Hippocampus/cytology , Mice , Neurons/drug effects , Nitriles , Pyridones/chemistry , Pyridones/pharmacology , Receptors, AMPA/antagonists & inhibitors , Receptors, AMPA/metabolism
5.
J Neurol Surg A Cent Eur Neurosurg ; 74(4): 228-33, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23526203

ABSTRACT

BACKGROUND: Although the anatomy of the Sylvian fissure is understood, there is little information on where to start its dissection in the pterional transsylvian (PT-TS) approach. At small craniotomy using the PT-TS approach, we set the entry point to the Sylvian fissure at 15 mm behind the anterior edge of the craniotomy along the Sylvian fissure and designated this site "point 15." Here we compared the utility of "point 15" with the Sylvian point (point on the Sylvian fissure giving rise to the horizontal and anterior ascending rami) that had been recommended earlier as the entry site for opening the Sylvian fissure. MATERIALS AND METHODS: This study includes 16 patients with 7 ruptured and 9 unruptured anterior circulation aneurysms. We evaluated the usefulness of "point 15" in the PT-TS approach for aneurysmal neck clipping with respect to the adequacy of anatomical exposure and low invasiveness. RESULTS: In 12 patients "point 15" provided for excellent anatomical exposure of the Sylvian fissure; complete neck clipping was possible with minimal brain retraction and damage. In two patients with ruptured aneurysms and thick subarachnoid hemorrhage and in two patients with unruptured aneurysms, the dissection had to be enlarged 3 to 4 mm distally without reaching the Sylvian point. In the latter two patients the Sylvian veins were tethered to frontal and temporal lobes. CONCLUSIONS: The "point 15" was an easily set entry point to the Sylvian fissure. It provided for sufficient anatomical exposure at surgery for anterior circulation aneurysms; additional posterior dissection was required in rare cases. We found that "point 15" was useful in small craniotomies using the PT-TS approach.


Subject(s)
Craniotomy/methods , Neurosurgical Procedures/methods , Skull/anatomy & histology , Skull/surgery , Adolescent , Adult , Aged , Aneurysm, Ruptured/surgery , Carotid Artery, Internal/surgery , Female , Humans , Image Processing, Computer-Assisted , Infarction, Middle Cerebral Artery/surgery , Intracranial Aneurysm/surgery , Intracranial Hemorrhages/surgery , Male , Middle Aged , Prospective Studies , Sphenoid Bone/anatomy & histology , Tomography, X-Ray Computed , Young Adult
6.
Rev Sci Instrum ; 82(9): 093905, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21974598

ABSTRACT

The authors report on a new depth profiling method of deep levels, which we call electrochemical isothermal-capacitance-transient spectroscopy (EICTS). This is combined with electrochemical capacitance-voltage using the Schottky barrier of etchable electrolyte and isothermal-capacitance-transient spectroscopy using the capacitance-transient profile at a fixed temperature. We proved its validity by applying to the ZnSe:N epitaxial film of thickness of more than 1000 nm and comparing the characteristics of an obtained deep level with the results measured by conventional deep-level detection techniques. It is expected that EICTS is very effective to assess the deep levels of wide-bandgap semiconductors that suffer from various point defects and their complexes.

7.
Kyobu Geka ; 59(6): 433-7; discussion 437-9, 2006 Jun.
Article in Japanese | MEDLINE | ID: mdl-16780061

ABSTRACT

In this study, 110 consecutive patients who had undergone off-pump coronary artery bypass (OPCAB) in the past 2 years were evaluated for early results of OPCAB. Patients were classified as a high-risk group (H group: 68 patients consisting of 46 men and 22 women) and a low-risk group (L group: 42 patients consisting of 31 men and 11 women), respectively, and were evaluated for the early operative results. No differences were noted between the H and L groups in the mean number of bypass grafts (2.9 +/- 0.9 in the H group, 2.9 +/- 0.9 in the L group), the rates of complete revascularization (85% in the H group, 93% in the L group), those of various graft materials bypassed, or those of sequential bypass. In all patients, we were able to undergo coronary revascularization by the aortic no-touch technique using arterial grafts exclusively. In the H group, 1 patient (1.5%) died in hospital, but no patients developed cerebral infarction postoperatively, and the frequency of complications was similar to that in the L group. The results of OPCAB for high-risk patients were good, and it was suggested that OPCAB using in situ arterial grafts was very useful particularly in patients with cerebrovascular diseases.


Subject(s)
Coronary Artery Bypass, Off-Pump/mortality , Coronary Disease/surgery , Epigastric Arteries/transplantation , Mammary Arteries/transplantation , Vascular Patency , Aged , Aged, 80 and over , Coronary Artery Bypass, Off-Pump/methods , Coronary Disease/mortality , Female , Hospital Mortality , Humans , Male , Middle Aged , Risk
8.
Kyobu Geka ; 59(4): 301-5, 2006 Apr.
Article in Japanese | MEDLINE | ID: mdl-16613148

ABSTRACT

UNLABELLED: We conducted ultrasonic decalcification on calcified annulus in patients with aortic stenosis (AS) using an ultrasonic operator, Sonopet (UST 2001) prior to aortic valve replacement (AVR). We studied the reliability of this method. SUBJECT AND METHOD: From January 2002 to August 2005, AVR was conducted for AS using the Sonopet in 45 patients, comprising of 18 male and 27 female subjects. The mean age was 73.3 +/- 9.7. RESULT: Artificial valves were successfully inserted at the intra-annular level in 37 patients and at the supra-annular level in 8 patients without conducting annular enlargement. In the patients with narrow annuli of less than 19 mm (23 patients), the preoperative mean annular diameter was 18.2 +/- 1.0 mm, but significantly larger artificial valves with an average diameter of 19.3 +/- 1.5 mm (p=0.003) were successfully inserted. CONCLUSION: AVR was proved to be safe and easy by previous ultrasonic decalcification of the annuls using the Sonopet. This method was very useful because it required no enlargement of aortic annulus.


Subject(s)
Aortic Valve Stenosis/surgery , Aortic Valve/surgery , Calcinosis/surgery , Debridement/methods , Heart Valve Prosthesis Implantation/methods , Lithotripsy/methods , Ultrasonic Therapy/methods , Aged , Aged, 80 and over , Aortic Valve/pathology , Aortic Valve Stenosis/pathology , Female , Humans , Male , Retrospective Studies , Treatment Outcome
9.
Article in English | MEDLINE | ID: mdl-12687406

ABSTRACT

Immune and inflammatory systems are controlled by multiple cytokines, including interleukins (ILs) and interferons. These cytokines exert their biological functions through Janus tyrosine kinases (JAKs) and STAT transcription factors. The CIS (cytokine-inducible SH2 protein) and SOCS (suppressors of cytokine signaling) are a family of intracellular proteins, several of which have emerged as key physiological regulators of cytokine responses, including those that regulate the inflammatory systems. In this review, we focused on the molecular mechanism of the action of CIS/SOCS family proteins and their roles in inflammatory diseases. Furthermore, we illustrate several approaches for treating inflammatory diseases by modulating extracellular and intracellular signaling pathways.


Subject(s)
Cytokines/physiology , Immediate-Early Proteins/physiology , Inflammation/etiology , Intracellular Signaling Peptides and Proteins , Repressor Proteins/physiology , Animals , Carrier Proteins/physiology , Humans , Immediate-Early Proteins/chemistry , Inflammation/physiopathology , Membrane Glycoproteins/physiology , Mice , Models, Biological , Receptors, Cell Surface/physiology , Repressor Proteins/chemistry , Signal Transduction , Suppressor of Cytokine Signaling 1 Protein , Suppressor of Cytokine Signaling 3 Protein , Suppressor of Cytokine Signaling Proteins , T-Lymphocytes/immunology , Toll-Like Receptors , Transcription Factors/physiology
10.
Exp Toxicol Pathol ; 55(4): 247-50, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14703769

ABSTRACT

On administration to rats at a subtoxic dose, the antibiotic nitrofurazone (NF) has been shown to increase hepatocyte DNA synthesis and liver weight in a dose-dependent manner, with no histological or biochemical evidence of cell damage or necrosis. Free radicals are implicated in NF metabolism, as well as in the DNA synthesis or cell proliferation induced by a number of other chemicals. In the present study, NF was given alone or concomitantly with the antioxidants N-acetylcysteine or cyanidanol. Antioxidants prevent the effects of free radicals. Co-administration decreased hepatocyte proliferation to the same level as the control. This suppression of NF-induced hepatocyte proliferation by antioxidants therefore strongly suggests that free radical production is involved in this process.


Subject(s)
Acetylcysteine/pharmacology , Anti-Infective Agents, Local/pharmacology , Antioxidants/pharmacology , Catechin/pharmacology , Hepatocytes/drug effects , Nitrofurazone/pharmacology , Administration, Oral , Animals , Anti-Infective Agents, Local/administration & dosage , Bromodeoxyuridine/metabolism , Cell Division/drug effects , Drug Antagonism , Drug Therapy, Combination , Hepatocytes/metabolism , Hepatocytes/pathology , Male , Nitrofurazone/administration & dosage , Rats , Rats, Inbred F344 , Specific Pathogen-Free Organisms
11.
Neuropharmacology ; 43(5): 868-76, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12384172

ABSTRACT

We previously demonstrated that cultured rat dorsal root ganglion (DRG) cells respond to stimulation with interleukin-1 beta (IL-1 beta) by releasing substance P (SP), and this response is regulated via the cyclooxygenase (COX)-2 pathway. In this study, to ascertain the interaction between nitric oxide (NO) and prostaglandins in primary afferent neurons, we investigated the effect of NO on the IL-1 beta-induced release of SP in cultured DRG cells. An NO donor, S-nitroso-N-acetyl-DL-penicillamine (SNAP), did not in itself evoke SP release. However, it potentiated the IL-1 beta-induced release of SP. Similarly, while SNAP did not elicit the expression of COX-2 mRNA, it potentiated the expression induced by IL-1 beta in cultured DRG cells, and this potentiation was significantly suppressed by the NO scavenger, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide (carboxy-PTIO). Moreover, SNAP also potentiated the expression of COX-2 protein induced by IL-1 beta in cultured DRG cells. The stimulatory effect of SNAP on the IL-1 beta-induced release of SP was completely inhibited on co-incubation with a selective COX-2 inhibitor, NS-398. 1H-[1,2,4]oxadiazolo[4,3-a]quinoxaline-1-one (ODQ), a potent inhibitor of soluble guanylate cyclase, did not suppress, and a membrane-permeable cGMP analogue, 8-Br-cGMP, did not mimic the stimulatory effects of SNAP in DRG cells. These results suggest that in cultured DRG cells, NO potentiates the IL-1 beta-induced increase in COX-2 expression via a soluble guanylate cyclase-cGMP-independent pathway, resulting in facilitation of SP release. The interaction between NO and COX in primary afferent neurons might contribute to the change in nociceptive perception in inflammatory hyperalgesia.


Subject(s)
Cyclic GMP/physiology , Interleukin-1/pharmacology , Isoenzymes/biosynthesis , Neurons, Afferent/metabolism , Nitric Oxide/pharmacology , Prostaglandin-Endoperoxide Synthases/biosynthesis , RNA, Messenger/biosynthesis , Substance P/metabolism , Animals , Blotting, Western , Cells, Cultured , Culture Media , Cyclooxygenase 2 , Drug Synergism , Enzyme Induction/drug effects , Ganglia, Spinal/cytology , Ganglia, Spinal/drug effects , Ganglia, Spinal/metabolism , Neurons, Afferent/drug effects , Nitric Oxide Donors/pharmacology , Rats , Rats, Wistar , S-Nitroso-N-Acetylpenicillamine/pharmacology , Up-Regulation/drug effects
12.
Genes Cells ; 6(12): 1019-30, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11737263

ABSTRACT

BACKGROUND: Metazoan mitochondrial (mt) tRNAs are structurally quite different from the canonical cloverleaf secondary structure. The mammalian mt tRNASerGCU for AGY codons (Y = C or U) lacks the entire D arm, whereas tRNASerUGA for UCN codons (N = A, G, C or U) has an extended anti-codon stem. It has been a long-standing problem to prove experimentally how these tRNAsSer work in the mt translation system. RESULTS: To solve the above-mentioned problem, we examined their translational abilities in an in vitro bovine mitochondrial translation system using transcripts of altered tRNASer analogues derived from bovine mitochondria. Both tRNASer analogues had almost the same ability to form ternary complexes with mt EF-Tu and GTP. The D-arm-lacking tRNASer GCU analogue had considerably lower translational activity than the tRNASerUGA analogue and produced mostly short oligopeptides, up to a tetramer. In addition, tRNASerGCU analogue was disfavoured by the ribosome when other tRNAs capable of decoding the cognate codon were available. CONCLUSION: Both mt tRNASerGCU and tRNASerUGA analogues with unusual secondary structure were found to be capable of translation on the ribosome. However, the tRNASerGCU analogue has some molecular disadvantage on the ribosome, which probably derives from the lack of a D arm.


Subject(s)
Protein Biosynthesis , RNA, Transfer, Ser/genetics , RNA/genetics , Animals , Base Sequence , Cattle , Codon , Guanosine Triphosphate/metabolism , In Vitro Techniques , Nucleic Acid Conformation , Peptide Elongation Factor Tu/metabolism , Polymers/chemistry , Protein Binding , RNA/chemistry , RNA, Mitochondrial , RNA, Transfer, Amino Acyl/genetics , RNA, Transfer, Phe/genetics , RNA, Transfer, Ser/chemistry , Transfer RNA Aminoacylation
13.
J Clin Invest ; 108(12): 1781-8, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11748261

ABSTRACT

Immune and inflammatory systems are controlled by multiple cytokines, including ILs and INFs. These cytokines exert their biological functions through Janus tyrosine kinases and STAT transcription factors. One such cytokine, IL-6, has been proposed to contribute to the development of rheumatoid arthritis (RA). We found that STAT3 was strongly tyrosine phosphorylated in synovial tissue of RA patients, but not those with osteoarthritis. Blockade of the IL-6-gp130-JAK-STAT3-signaling pathway might therefore be beneficial in the treatment of RA. We show here that the mRNA for the endogenous cytokine signaling repressor CIS3/SOCS3 is abundantly expressed in RA patients. To determine whether CIS3 is effective in treating experimental arthritis, a recombinant adenovirus carrying the CIS3 cDNA was injected periarticularly into the ankle joints of mice with antigen-induced arthritis or collagen-induced arthritis (CIA). Periarticular injection of CIS3 adenovirus drastically reduced the severity of arthritis and joint swelling compared with control groups. CIS3 was more effective than a dominant-negative form of STAT3 in the CIA model. Thus, induction of CIS3 could represent a new approach for effective treatment of RA.


Subject(s)
Arthritis, Rheumatoid/therapy , Genetic Therapy , Proteins/genetics , Repressor Proteins , Signal Transduction , Transcription Factors , Animals , Cell Division , DNA-Binding Proteins/physiology , Disease Models, Animal , Humans , Interleukin-6/analysis , Male , Mice , Mice, Inbred C57BL , Mice, Inbred DBA , Proteins/physiology , RNA, Messenger/analysis , STAT3 Transcription Factor , Suppressor of Cytokine Signaling 3 Protein , Suppressor of Cytokine Signaling Proteins , Trans-Activators/physiology
14.
Biochem Biophys Res Commun ; 289(1): 225-8, 2001 Nov 23.
Article in English | MEDLINE | ID: mdl-11708803

ABSTRACT

Neuromedin U (NMU) is a hypothalamic peptide that has been recently found to reduce food intake, but few is known about its other functions in the central nervous system. We here studied behavioral activities induced by an intracerebroventricular (ICV) administration of NMU in rats and mice. NMU increased gross locomotor activity, face washing behavior, and grooming. NMU-induced stress response was significantly abolished by pretreatment with an antagonist of corticotropin-releasing hormone (CRH), alpha-helical CRH (9-41) (alpha-hCRH), or anti-CRH IgG. NMU did not induce locomotor activity in CRH knockout mice. NMU that interacts anatomically and/or functionally with the CRH system is a novel physiological regulator of stress response.


Subject(s)
Neuropeptides/pharmacology , Stress, Physiological/physiopathology , Animals , Behavior, Animal/drug effects , Behavior, Animal/physiology , Corticotropin-Releasing Hormone/administration & dosage , Corticotropin-Releasing Hormone/antagonists & inhibitors , Corticotropin-Releasing Hormone/deficiency , Corticotropin-Releasing Hormone/genetics , Grooming/drug effects , Grooming/physiology , Injections, Intraventricular , Male , Mice , Mice, Knockout , Motor Activity/drug effects , Motor Activity/physiology , Neuropeptides/administration & dosage , Neuropeptides/physiology , Rats , Rats, Wistar
15.
J Clin Invest ; 108(10): 1459-67, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11714737

ABSTRACT

The gp130 cytokine receptor activates a cardiomyocyte survival pathway during the transition to heart failure following the biomechanical stress of pressure overload. Although gp130 activation is observed transiently during transverse aortic constriction (TAC), its mechanism of inactivation is largely unknown in cardiomyocytes. We show here that suppressor of cytokine signaling 3 (SOCS3), an intrinsic inhibitor of JAK, shows biphasic induction in response to TAC. The induction of SOCS3 was closely correlated with STAT3 phosphorylation, as well as the activation of an embryonic gene program, suggesting that cardiac gp130-JAK signaling is precisely controlled by this endogenous suppressor. In addition to its cytoprotective action, gp130-dependent signaling induces cardiomyocyte hypertrophy. Adenovirus-mediated gene transfer of SOCS3 to ventricular cardiomyocytes completely suppressed both hypertrophy and antiapoptotic phenotypes induced by leukemia inhibitory factor (LIF). To our knowledge, this is the first clear evidence that these two separate cardiomyocyte phenotypes induced by gp130 activation lie downstream of JAK. Three independent signaling pathways, STAT3, MEK1-ERK1/2, and AKT activation, that are coinduced by LIF stimulation were completely suppressed by SOCS3 overexpression. We conclude that SOCS3 is a mechanical stress-inducible gene in cardiac muscle cells and that it directly modulates stress-induced gp130 cytokine receptor signaling as the key molecular switch for a negative feedback circuit for both myocyte hypertrophy and survival.


Subject(s)
Antigens, CD/physiology , Cardiomegaly , Cell Survival/physiology , Membrane Glycoproteins/physiology , Myocardium/pathology , Proteins/metabolism , Repressor Proteins , Signal Transduction , Transcription Factors , Animals , Antigens, CD/metabolism , Cytokine Receptor gp130 , Membrane Glycoproteins/metabolism , Mice , Mice, Inbred C57BL , Myocardium/metabolism , Suppressor of Cytokine Signaling 3 Protein , Suppressor of Cytokine Signaling Proteins
16.
J Biol Chem ; 276(44): 40746-54, 2001 Nov 02.
Article in English | MEDLINE | ID: mdl-11522790

ABSTRACT

Cytokines exert biological functions by activating Janus tyrosine kinases (JAKs), and JAK inhibitors JAB (also referred to as SOCS1 and SSI1) and CIS3 (SOCS3) play an essential role in the negative regulation of cytokine signaling. We have found that transgenic (Tg) mice expressing a mutant JAB (F59D-JAB) exhibited a more potent STAT3 activation and a more severe colitis than did wild-type littermates after treatment with dextran sulfate sodium. We now find that there is a prolonged activation of JAKs and STATs in response to a number of cytokines in T cells from Tg mice with lck promoter-driven F59D-JAB. Overexpression of F59D-JAB also sustained activation of JAK2 in Ba/F3 cells. These data suggested that F59D-JAB up-regulated STAT activity by sustaining JAK activation. To elucidate molecular mechanisms related to F59D-JAB, we analyzed the effects of F59D-JAB on the JAK/STAT pathway using the 293 cell transient expression system. We found that the C-terminal SOCS-box played an essential role in augmenting cytokine signaling by F59D-JAB. The SOCS-box interacted with the Elongin BC complex, and this interaction stabilized JAB. F59D-JAB induced destabilization of wild-type JAB, whereas overexpression of Elongin BC canceled this effect. Levels of endogenous JAB and CIS3 in T cells from F59D-JAB Tg-mouse were lower than in wild-type mice. We propose that F59D-JAB destabilizes wild-type, endogenous JAB and CIS3 by chelating the Elongin BC complex, thereby sustaining JAK activation.


Subject(s)
Carrier Proteins/physiology , Cytokines/physiology , DNA-Binding Proteins/metabolism , Intracellular Signaling Peptides and Proteins , Protein-Tyrosine Kinases/metabolism , Repressor Proteins , Signal Transduction/physiology , Trans-Activators/metabolism , Base Sequence , Carrier Proteins/genetics , Cell Line , DNA Primers , Humans , Hydrolysis , Mutation , Polymerase Chain Reaction , Precipitin Tests , STAT3 Transcription Factor , Suppressor of Cytokine Signaling 1 Protein , Suppressor of Cytokine Signaling Proteins , Transcription, Genetic/physiology
18.
J Biol Chem ; 276(35): 33181-95, 2001 Aug 31.
Article in English | MEDLINE | ID: mdl-11402041

ABSTRACT

The mammalian mitochondrial ribosome (mitoribosome) has a highly protein-rich composition with a small sedimentation coefficient of 55 S, consisting of 39 S large and 28 S small subunits. In the previous study, we analyzed 39 S large subunit proteins from bovine mitoribosome (Suzuki, T., Terasaki, M., Takemoto-Hori, C., Hanada, T., Ueda, T., Wada, A., and Watanabe, K. (2001) J. Biol. Chem. 276, 21724-21736). The results suggested structural compensation for the rRNA deficit through proteins of increased molecular mass in the mitoribosome. We report here the identification of 28 S small subunit proteins. Each protein was separated by radical-free high-reducing two-dimensional polyacrylamide gel electrophoresis and analyzed by liquid chromatography/mass spectrometry/mass spectrometry using electrospray ionization/ion trap mass spectrometer to identify cDNA sequence by expressed sequence tag data base searches in silico. Twenty one proteins from the small subunit were identified, including 11 new proteins along with their complete cDNA sequences from human and mouse. In addition to these proteins, three new proteins were also identified in the 55 S mitoribosome. We have clearly identified a mitochondrial homologue of S12, which is a key regulatory protein of translation fidelity and a candidate for the autosomal dominant deafness gene, DFNA4. The apoptosis-related protein DAP3 was found to be a component of the small subunit, indicating a new function for the mitoribosome in programmed cell death. In summary, we have mapped a total of 55 proteins from the 55 S mitoribosome on the two-dimensional polyacrylamide gels.


Subject(s)
Mitochondria, Liver/chemistry , Phylogeny , Proteome/chemistry , Ribosomal Proteins/chemistry , Ribosomes/chemistry , Amino Acid Sequence , Animals , Bacteria/genetics , Caenorhabditis elegans/genetics , Cattle , Chromatography, Liquid , DNA, Complementary , Drosophila melanogaster/genetics , Humans , Mammals , Mass Spectrometry , Mice , Mitochondria, Liver/genetics , Models, Molecular , Molecular Sequence Data , Molecular Weight , Peptide Fragments/chemistry , Protein Structure, Secondary , Recombinant Proteins/chemistry , Ribosomal Proteins/genetics , Ribosomal Proteins/isolation & purification , Ribosomes/genetics , Saccharomyces cerevisiae/genetics
19.
J Am Chem Soc ; 123(25): 5947-55, 2001 Jun 27.
Article in English | MEDLINE | ID: mdl-11414828

ABSTRACT

The complementary 1,omega-thymine, 1,omega-adenine, and 1,omega-(thymine, adenine) bolaamphiphiles, [N,N'-bis[3-(2,4-dihydroxy-5-methylpyrimidine-1-yl)propionyl]1,n-diaminoalkane [T-n-T (n = 10, 11, 12)], N, N'-bis[3-(6-aminopurine-9-yl)propionyl]1,n-diaminoalkane [A-n-A (n = 10, 11, 12)], and N-[3-(2,4-dihydroxy-5-methylpyrimidine-1-yl)propionyl], N'-[3-(6-aminopurine-9-yl)propionyl]1,n-diaminoalkane [T-n-A (n = 10, 11, 12)], respectively] have been synthesized. The spontaneous homo- and heteroassembly of these nucleobase-based bolaamphiphiles has been studied by light microscopy, energy-filtering transmission electron microscopy, FT-IR, and powder X-ray diffraction analyses. The achiral T-10-T bolaamphiphile produced in 10% ethanolic/aqueous solutions unprecedented double-helical ropes of 1-2 microm in widths and several hundred micrometers in length, whereas the complementary homologue A-10-A gave only microcrystalline solids of 1-10 microm in size. In contrast, an equimolar mixture of T-10-T and A-10-A yielded supramolecular fibers of 15-30 nm in width. (1)H NMR, CD, and UV studies of solution photoreactions of T-10-T suggested that under natural light the chiral rope formation is triggered by photodimerization of trace amounts of the thymine moieties in the T-10-T assemblies. Complementary hydrogen bond formation between the thymine-adenine heterobase pairs was found to prevent such a photoreaction and resulted in no chiral rope formation. The heteroditopic T-12-A bolaamphiphile self-assembled to form supramolecular fibers. Multilamellar organization was proposed for the homo- and heteroassemblies made of T-n-T and A-n-A.


Subject(s)
Adenine/chemistry , Surface-Active Agents/chemistry , Surface-Active Agents/chemical synthesis , Thymine/chemistry , Microscopy , Microscopy, Electron , Spectroscopy, Fourier Transform Infrared , Structure-Activity Relationship , X-Ray Diffraction
20.
Exp Toxicol Pathol ; 53(1): 25-30, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11370730

ABSTRACT

Fenoldopam, a dopaminergic (DA1) agonist, has been reported to induce medial necrosis and adventitial inflammatory response in the splanchnic arteries in rats. This study was carried out to clarify the detailed time course of the inflammatory responses, using antibodies for the inflammatory cell markers, CD3 (T cell), CD20 (B cell) and ED-1 (macrophage), and inflammatory serum factors, IgG, IgM and C3. Rats were administered fenoldopam for 24 hours by intravenous infusion. Histopathologically, medial necrosis with hemorrhage was observed at the end of infusion, but it almost disappeared on day 7 post-infusion. Adventitial inflammatory responses with ED-1-, CD3- and CD20-positive cells were very slight at the end of infusion, became prominent with marked fibrosis on days 3 and 5, decreased on day 7, and subsided on day 14. The serum factors were first present in the area of medial necrosis, then shifted to the subendothelial space or cytoplasm of smooth muscle cells, and disappeared on day 14 post-infusion. Gaps in the external elastic lamina were observed on days 3 and 5 post-infusion, and IgG and IgM were present outside the gaps in the adventitia. These results provided us with more detailed information on the inflammatory responses following medial damage induced by vasodilators.


Subject(s)
Arteritis/chemically induced , Fenoldopam/toxicity , Vasodilator Agents/toxicity , Animals , Antigens, CD20/analysis , Arteritis/metabolism , Arteritis/pathology , Biomarkers/analysis , CD3 Complex/analysis , Epidermal Growth Factor/analysis , Fluorescent Antibody Technique, Indirect , Hemorrhage/chemically induced , Hemorrhage/pathology , Heparin-binding EGF-like Growth Factor , Immunoenzyme Techniques , Immunoglobulin G/analysis , Immunoglobulin M/analysis , Infusions, Intravenous , Intercellular Signaling Peptides and Proteins , Male , Rats , Rats, Inbred F344 , Time Factors , Tunica Media/drug effects , Tunica Media/metabolism , Tunica Media/pathology
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