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1.
J Chem Phys ; 160(2)2024 Jan 14.
Article in English | MEDLINE | ID: mdl-38189806

ABSTRACT

To spectroscopically qualify strength in the π-electron conjugation, the electronic spectra of jet-cooled 1,4-bis(phenylethynyl)benzene (BPEB) in the region of the transition to the lowest excited singlet (S1) 1B1u state are measured by the fluorescence excitation and the single-vibronic-level dispersed fluorescence methods. Strength is defined as the difference in potential energies between the planar and perpendicular conformations. BPEB possesses two large-amplitude torsional motions, out-of-phase 24 and in-phase 29 modes. The most stable is the planar conformation, and barrier heights at the perpendicular conformation are coincident in torsional potentials for the two modes. Torsional levels are successively observed up to 19± and 16- quantum levels in the ground state, respectively. Strength is determined to be 293 cm-1 (3.51 kJmol-1) with an accuracy of an error range smaller than 1 cm-1. In the excited state, strength is estimated to be 1549 ± 73 cm-1. Combination levels of two torsional modes are also measured up to high quantum levels. A systematic decrease in frequencies is observed with increasing the quantum number. Quantum-chemistry calculations of B3LYP, CAM-B3PLYP, WB97XD, and M062X with basis sets of aug-cc-pVDZ are performed, where B3LYP theories are carried out with the dispersion correlation. The calculated strength is 1.1-2.1 times larger than observed.

2.
Ann Thorac Surg ; 113(6): 1891-1900, 2022 06.
Article in English | MEDLINE | ID: mdl-34186094

ABSTRACT

BACKGROUND: Critical obstacles must be addressed before clinical application of artificial tracheas. The major complications of long tracheal replacement include anastomotic dehiscence and stenosis owing to poor vascularity and incomplete reepithelialization. The objective of this report was to clarify whether preincubation of the prosthesis in the omentum could be applicable for reconstruction of a long segment of the intrathoracic trachea in a canine model. METHODS: The framework of an artificial trachea was fabricated from a polypropylene mesh tube and coated with 1% neutral atelocollagen inside and outside the lumen. The prosthesis was placed in the omentum of 9 healthy male beagle dogs for 3 weeks. Then, the pedicled prosthesis was used to replace a 50-mm-long section of intrathoracic trachea. Results were evaluated bronchoscopically, macroscopically, and histologically. RESULTS: After 3 weeks of abdominal incubation, the prostheses were incorporated into the host tissue. None of the dogs showed dehiscence of the anastomosis or infection of the prostheses during the postoperative period. Seven of the 9 dogs survived for more than 1 year. One dog died of a bowel obstruction resulting from a diaphragmatic hernia 3 months after replacement, and another died due to reasons unrelated to the prosthesis at 6 months. Bronchoscopic examination revealed no stenosis or dehiscence, and microscopic examination of all dogs showed that the luminal surface was covered by newly regenerated connective tissue and respiratory epithelium. CONCLUSIONS: Pedicled omentum-prosthesis complexes may allow successful reconstruction of a long segment of the intrathoracic trachea.


Subject(s)
Prostheses and Implants , Trachea , Animals , Dogs , Humans , Male , Polypropylenes , Prosthesis Design , Prosthesis Implantation , Tissue Engineering/methods , Trachea/pathology , Trachea/surgery
3.
Chemistry ; 27(3): 1127-1137, 2021 Jan 13.
Article in English | MEDLINE | ID: mdl-33020962

ABSTRACT

A semiconductor-metal-complex hybrid photocatalyst was previously reported for CO2 reduction; this photocatalyst is composed of nitrogen-doped Ta2 O5 as a semiconductor photosensitizer and a Ru complex as a CO2 reduction catalyst, operating under visible light (>400 nm), with high selectivity for HCOOH formation of more than 75 %. The electron transfer from a photoactive semiconductor to the metal-complex catalyst is a key process for photocatalytic CO2 reduction with hybrid photocatalysts. Herein, the excited-state dynamics of several hybrid photocatalysts are described by using time-resolved emission and infrared absorption spectroscopies to understand the mechanism of electron transfer from a semiconductor to the metal-complex catalyst. The results show that electron transfer from the semiconductor to the metal-complex catalyst does not occur directly upon photoexcitation, but that the photoexcited electron transfers to a new excited state. On the basis of the present results and previous reports, it is suggested that the excited state is a charge-transfer state located between shallow defects of the semiconductor and the metal-complex catalyst.

4.
Inorg Chem ; 58(17): 11480-11492, 2019 Sep 03.
Article in English | MEDLINE | ID: mdl-31418554

ABSTRACT

The supramolecular photocatalysts in which a Ru(II) complex as a molecular redox photosensitizer unit and a Re(I) complex as a molecular catalyst unit are connected with a various alkyl or ether chain have attracted attention because they can efficiently photocatalyze CO2 reduction with high durability and high selectivity of CO formation, especially on various solid materials such as semiconductor electrodes and mesoporous organosilica. The intramolecular electron transfer from the one-electron reduced photosensitizer unit to the catalyst unit, which follows excitation of the photosensitizer unit and subsequent reductive quenching of the excited photosensitizer unit by a reductant, is one of the most important processes in the photocatalytic reduction of CO2. We succeeded in determining the rate constants of this intramolecular electron transfer process by using subnanosecond time-resolved IR spectroscopy. The logarithm of rate constants shows a linear relationship with the lengths of the bridging chain in the supramolecular photocatalysts with one bridging alkyl or ether chain. In conformity with the exponential decay of the wave function and the coupling element in the long-distance electron transfer, the apparent decay coefficient factor (ß) in the supramolecular photocatalysts with one bridging chain was determined to be 0.74 Å-1. In the supramolecular photocatalyst with two ethylene chains connecting between the photosensitizer and catalyst units, on the other hand, the intramolecular electron transfer rate is much faster than that with only one ethylene chain. These results strongly indicate that the intramolecular electron transfer from the one-electron reduced species of the Ru photosensitizer unit to the Re catalyst unit proceeds by the through-bond mechanism.

5.
J Phys Chem Lett ; 10(10): 2475-2480, 2019 May 16.
Article in English | MEDLINE | ID: mdl-30973013

ABSTRACT

Thermally activated delayed fluorescence (TADF) molecules are gathering attention for their potential to boost the efficiency of organic light-emitting diodes without precious metals. Minimizing the energy difference between the S1 and T1 states (Δ EST) is a fundamental strategy to accelerate reverse intersystem crossing (RISC). However, the lack of microscopic understanding of the process prevents adequate design strategies for efficient TADF materials. Here, we focused on four carbazole-benzonitrile (Cz-BN) derivatives that possess identical Δ EST but distinct TADF activities. We systematically compared their geometrical dynamics upon photoexcitation using time-resolved infrared (TR-IR) vibrational spectroscopy in conjunction with quantum chemical calculations. We found that the most TADF-active molecule, 4CzBN, shows little structural change after photoexcitation, while the TADF-inactive molecules show relatively large deformation upon S1-T1 conversion. This implies that the suppression of structural deformation is critical for minimizing the activation energy barrier for RISC in cases of the Cz-BN derivatives.

6.
Endocr J ; 65(4): 493-498, 2018 Apr 26.
Article in English | MEDLINE | ID: mdl-29459556

ABSTRACT

We describe a very rare case of concurrent variant type 3 autoimmune polyglandular syndrome (APS) and pulmonary arterial hypertension (PAH). A previously healthy 65-year-old Japanese woman was referred to our university hospital with a 2-month history of general fatigue and hyperglycemia. Laboratory tests revealed severe hyperglycemia (plasma glucose 543 mg/dL and HbA1c 10.7%) with ketonuria (3+). Glutamic acid decarboxylase (GAD) and IA-2 antibodies were positive, and the serum C peptide level was markedly decreased to 0.2 ng/mL. Accordingly, type 1 diabetes was diagnosed. Hashimoto's thyroiditis was also diagnosed because she had a diffuse goiter and a mild hypothyroidism (TSH 8.20 µU/mL, and FT4 0.80 ng/mL) with positive autoantibodies for thyroid peroxidase and thyroglobulin. There was neither adrenal insufficiency nor hypocalcemia. In addition, chest X ray showed a suspicious PAH by a dilation of both pulmonary arteries, especially right descending artery, and right heart catheterization confirmed the presence of PAH. HLA Class II genotyping revealed DRB1-DQB1*0901-*0303, a common susceptibility haplotype in Japanese patients with type 3 APS or acute-onset type 1 diabetes. The combination of variant type 3 APS and PAH is extremely rare and to the best of knowledge, this is the first case reported in a Japanese patient.


Subject(s)
Blood Glucose/metabolism , HLA-DQ beta-Chains/genetics , Hypertension, Pulmonary/complications , Polyendocrinopathies, Autoimmune/complications , Aged , Alleles , Female , Genetic Predisposition to Disease , Haplotypes , Humans , Hypertension, Pulmonary/blood , Hypertension, Pulmonary/genetics , Japan , Polyendocrinopathies, Autoimmune/blood , Polyendocrinopathies, Autoimmune/genetics
7.
Exp Anim ; 67(2): 185-192, 2018 May 10.
Article in English | MEDLINE | ID: mdl-29187699

ABSTRACT

A relationship between Alzheimer's disease and herpes simplex virus infection has been pointed out. We established a model of Alzheimer's disease with a latent herpesvirus infection using a mouse model of Alzheimer's disease (PS2Tg2576) and examined the changes in amyloid ß (Aß) in the brain. We crossbred female PS2 mice with male Tg2576 hemi mice and chose PS2Tg2576 mice. After priming 5-week-old male mice with anti-pseudorabies virus swine serum, we challenged the mouse with 100 LD50 of YS-81, a wild-type strain of pseudorabies virus. The viral DNA was detected in nasal swabs by a reactivation test and in the trigeminal ganglia. At two months after infection, the Aß40 and Aß42 levels in the brains of the mice of the latently infected group were increased; the increase was greater than that observed in the noninfected group. Latent pseudorabies virus infection was established in PS2Tg2576 mice and the level of Aß increased with the reactivation of the latent virus.


Subject(s)
Alzheimer Disease , Disease Models, Animal , Mice, Transgenic , Pseudorabies , Trefoil Factor-1/genetics , Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Animals , Brain/metabolism , DNA, Viral/metabolism , Female , Herpesvirus 1, Suid/genetics , Herpesvirus 1, Suid/physiology , Male , Pseudorabies/virology , Virus Activation
8.
J Am Chem Soc ; 139(44): 15792-15800, 2017 11 08.
Article in English | MEDLINE | ID: mdl-29037042

ABSTRACT

Aromaticity of photoexcited molecules is an important concept in organic chemistry. Its theory, Baird's rule for triplet aromaticity since 1972 gives the rationale of photoinduced conformational changes and photochemical reactivities of cyclic π-conjugated systems. However, it is still challenging to monitor the dynamic structural change induced by the excited-state aromaticity, particularly in condensed materials. Here we report direct structural observation of a molecular motion and a subsequent packing deformation accompanied by the excited-state aromaticity. Photoactive liquid crystal (LC) molecules featuring a π-expanded cyclooctatetraene core unit are orientationally ordered but loosely packed in a columnar LC phase, and therefore a photoinduced conformational planarization by the excited-state aromaticity has been successfully observed by time-resolved electron diffractometry and vibrational spectroscopy. The structural change took place in the vicinity of excited molecules, producing a twisted stacking structure. A nanoscale torque driven by the excited-state aromaticity can be used as the working mechanism of new photoresponsive materials.

9.
Org Lett ; 19(10): 2564-2567, 2017 05 19.
Article in English | MEDLINE | ID: mdl-28485606

ABSTRACT

Straightforward syntheses leading to π-extended benzosilolothiophene (BST) derivatives by Rh-catalyzed dehydrogenative cyclization reactions have been developed. Electron-deficient ligands were effective for the reactions, and dppe-F20 gave the best result. This method could be applied to the synthesis of highly π-extended ladder-type BST derivatives, which exhibited fluorescence.

10.
Biochem Biophys Res Commun ; 486(4): 1055-1061, 2017 05 13.
Article in English | MEDLINE | ID: mdl-28366629

ABSTRACT

Starfish oocytes are arrested at the prophase stage of the first meiotic division in the ovary. They resume meiosis by the stimulus of 1-methyladenine (1-MeAde), the maturation-inducing hormone for starfish oocytes. Putative 1-MeAde receptors have been suggested to be present on the oocyte surface, but not yet been characterized biochemically. As reported recently (T. Toraya, T. Kida, A. Kuyama, S. Matsuda, S. Tanaka, Y. Komatsu, T. Tsurukai, Biochem. Biophys. Res. Commun. 485 (2017) 41-46), it became possible to detect unknown 1-MeAde binders of starfish oocytes by immunophotoaffinity labeling, i.e., photoaffinity labeling combined with immunochemical detection. We designed and synthesized water-soluble and insoluble polymer-bound 1-MeAde derivatives. A water-soluble polymer-bound 1-MeAde derivative, in which 1-MeAde is bound to dextran through an N6-substituent, triggered the germinal-vesicle breakdown toward follicle-free oocytes, dejellied oocytes, and denuded oocytes. This is consistent with the idea that putative 1-MeAde receptors are located on the cell surface of starfish oocytes. A water-insoluble polymer-bound 1-MeAde derivative, in which 1-MeAde is bound to Sepharose 4B through an N6-substituent, served as an effective affinity adsorbent for the partial purification of a 1-MeAde binder with Mr of 47.5 K that might be a possible candidate of the maturation-inducing hormone receptors of starfish oocytes.


Subject(s)
Adenine/analogs & derivatives , Chromatography, Affinity/methods , Excipients/chemistry , Oocytes/metabolism , Starfish/metabolism , Adenine/chemistry , Adenine/metabolism , Animals , Cells, Cultured , Female , Oocytes/growth & development , Oogenesis/physiology
11.
Biochem Biophys Res Commun ; 485(1): 41-46, 2017 03 25.
Article in English | MEDLINE | ID: mdl-28174006

ABSTRACT

Starfish oocytes are arrested at the prophase stage of the first meiotic division in the ovary and resume meiosis by the stimulus of 1-methyladenine (1-MeAde), the oocyte maturation-inducing hormone of starfish. Putative 1-MeAde receptors on the oocyte surface have been suggested, but not yet been biochemically characterized. Immunophotoaffinity labeling, i.e., photoaffinity labeling combined with immunochemical detection, was attempted to detect unknown 1-MeAde binders including putative maturation-inducing hormone receptors in starfish oocytes. When the oocyte crude membrane fraction or its Triton X-100/EDTA extract was incubated with N6-[6-(5-azido-2-nitrobenzoyl)aminohexyl]carboxamidomethyl-1-methyladenine and then photo-irradiated, followed by western blotting with antibody that was raised against a 1-MeAde hapten, a single band with Mr of 47.5 K was detected. The band was lost when extract was heated at 100 °C. A similar 47.5 K band was detected in the crude membrane fraction of testis as well. Upon labeling with whole cells, this band was detected in immature and maturing oocytes, but only faintly in mature oocytes. As judged from these results, this 1-MeAde binder might be a possible candidate of the starfish maturation-inducing hormone receptors.


Subject(s)
Adenine/analogs & derivatives , Blotting, Western , Oocytes/metabolism , Oogenesis , Photoaffinity Labels/metabolism , Starfish/physiology , Adenine/metabolism , Animals , Blotting, Western/methods , Female , Oocytes/cytology , Photoaffinity Labels/chemical synthesis , Photoaffinity Labels/chemistry
12.
Intern Med ; 56(1): 17-21, 2017.
Article in English | MEDLINE | ID: mdl-28049995

ABSTRACT

Objective The goal of the present study was to investigate the plasma hydrogen sulfide (H2S) levels in patients with type 2 diabetes, as the plasma H2S levels in Japanese patients with type 2 diabetes remain unclear. Methods The plasma H2S levels were measured in 154 outpatients with type 2 diabetes and 66 outpatients without diabetes. All blood samples were collected in the outpatient department from 09:00 to 10:00. The patients had fasted from 21:00 the previous evening and had not consumed alcohol or caffeine or smoked until sample collection. The plasma H2S levels were measured using the methylene blue assay. The plasma H2S levels were determined in triplicate, and the average concentrations were calculated against a calibration curve of sodium sulfide. Results The patients with type 2 diabetes showed a progressive reduction in the plasma H2S levels (45.115.5 M versus 54.026.4 M, p<0.05), which paralleled poor glycemic control. There was a significant correlation between a reduction in the plasma H2S levels and the HbA1c levels (=-0.505, p<0.01), Furthermore, a reduction in the plasma H2S levels was found to be related to a history of cardiovascular diseases in patients with type 2 diabetes (39.913.8 M versus 47.515.9 M, p<0.01). Conclusion Collectively, the plasma H2S levels were reduced in patients with type 2 diabetes, which may have implications in the pathophysiology of cardiovascular disease in diabetic patients. The trial was registered with the University Hospital Medical Information Network (UMIN no. #000020549).


Subject(s)
Cardiovascular Diseases/blood , Cardiovascular Diseases/physiopathology , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/physiopathology , Glycated Hemoglobin/analysis , Hydrogen Sulfide/blood , Animals , Asian People , Healthy Volunteers , Humans , Japan , Male
13.
Cardiovasc Diabetol ; 15: 76, 2016 May 17.
Article in English | MEDLINE | ID: mdl-27184495

ABSTRACT

BACKGROUND: The aim of the present study was to elucidate the effect of teneligliptin on oxidative stress and endothelial function in Japanese patients with type 2 diabetes and chronic kidney disease (CKD). METHODS: Forty-five patients with type 2 diabetes and CKD who received sitagliptin for at least 12 months were randomized to either continue sitagliptin (n = 23) or switch to teneligliptin (n = 22) for 24 weeks. The following parameters were evaluated at baseline and after 24 weeks of treatment with continued sitagliptin or teneligliptin: blood pressure, haemoglobin A1c (HbA1c), estimated glomerular filtration rate (eGFR), urinary albumin excretion, endothelial function by reactive hyperaemia index (RHI; EndoPAT(®) system), reactive oxygen metabolites (ROMs) measured by the d-ROMS test, 8-hydroxy-2'-deoxyguanosine, urinary liver-type fatty acid binding protein (L-FABP), and urinary 8-isoprostane. RESULTS: The two groups did not significantly differ with regard to age, male-to-female ratio, duration of diabetes, body mass index, HbA1c, eGFR, or urinary albumin excretion levels at baseline. We found no significant differences in changes of HbA1c, eGFR, or urinary albumin excretion levels between the two groups after 24 weeks of treatment. However, treatment with teneligliptin, but not sitagliptin, significantly improved RHI values and was correlated with the percent changes in RHI and d-ROMs. CONCLUSIONS: The present study demonstrated that teneligliptin, can improve endothelial function and reduce renal and vascular oxidative stress in patients with type 2 diabetes and CKD, independently of reducing albuminuria or improving glucose control. Trial registration UMIN000017180.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Oxidative Stress/drug effects , Pyrazoles/pharmacology , Renal Insufficiency, Chronic/drug therapy , Thiazolidines/pharmacology , Aged , Aged, 80 and over , Albuminuria/drug therapy , Case-Control Studies , Diabetes Mellitus, Type 2/complications , Endothelium/drug effects , Endothelium/metabolism , Female , Humans , Male , Middle Aged , Renal Insufficiency, Chronic/complications , Treatment Outcome
14.
Rev Sci Instrum ; 85(8): 083705, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25173274

ABSTRACT

We constructed an instrument for time-resolved photoemission electron microscopy (TR-PEEM) utilizing femtosecond (fs) laser pulses to visualize the dynamics of photogenerated electrons in semiconductors on ultrasmall and ultrafast scales. The spatial distribution of the excited electrons and their relaxation and/or recombination processes were imaged by the proposed TR-PEEM method with a spatial resolution about 100 nm and an ultrafast temporal resolution defined by the cross-correlation of the fs laser pulses (240 fs). A direct observation of the dynamical behavior of electrons on higher resistivity samples, such as semiconductors, by TR-PEEM has still been facing difficulties because of space and/or sample charging effects originating from the high photon flux of the ultrashort pulsed laser utilized for the photoemission process. Here, a regenerative amplified fs laser with a widely tunable repetition rate has been utilized, and with careful optimization of laser parameters, such as fluence and repetition rate, and consideration for carrier lifetimes, the electron dynamics in semiconductors were visualized. For demonstrating our newly developed TR-PEEM method, the photogenerated carrier lifetimes around a nanoscale defect on a GaAs surface were observed. The obtained lifetimes were on a sub-picosecond time scale, which is much shorter than the lifetimes of carriers observed in the non-defective surrounding regions. Our findings are consistent with the fact that structural defects induce mid-gap states in the forbidden band, and that the electrons captured in these states promptly relax into the ground state.

15.
Diabetes Technol Ther ; 16(12): 840-5, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25144424

ABSTRACT

BACKGROUND: This study investigated whether teneligliptin, a novel dipeptidyl peptidase-4 inhibitor, ameliorated glucose fluctuations in hospitalized Japanese patients with type 2 diabetes receiving insulin therapy, with or without other antidiabetes drugs, and using continuous glucose monitoring (CGM). PATIENTS AND METHODS: Twenty-six patients with type 2 diabetes were admitted for glycemic control. After admission, patients continued to be treated with optimal dietary therapy plus insulin therapy, with or without other antidiabetes drugs, until they achieved stable glycemic control. CGM measurements were made for 7 consecutive days. On Days 1-3, patients received insulin with or without other antidiabetes drugs, and on Days 4-7, teneligliptin 20 mg once daily at breakfast was added to ongoing therapy. Doses of insulin were fixed during the study. Levels of serum glycated albumin (GA), 1,5-anhydro-d-glucitol (1,5-AG), and high-sensitivity C-reactive protein (hsCRP) were measured. RESULTS: Add-on treatment with teneligliptin led to significant improvements in 24-h mean glucose levels, the proportion of time in normoglycemia, mean amplitude of glycemic excursions, and total area under the curve within 2 h after each meal. The proportion of time in hypoglycemia and hsCRP levels did not increase significantly compared with before teneligliptin. Values of 1,5-AG and GA were significantly improved by treatment with teneligliptin. CONCLUSIONS: Addition of teneligliptin to insulin therapy led to a significant improvement in diurnal glycemic control and significant reductions in glucose fluctuations in 24-h periods without increasing hypoglycemia in Japanese patients with type 2 diabetes on insulin therapy, with or without other antidiabetes agents.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Dipeptidyl-Peptidase IV Inhibitors/therapeutic use , Drug Resistance , Hyperglycemia/prevention & control , Hypoglycemia/prevention & control , Insulin/therapeutic use , Pyrazoles/therapeutic use , Thiazolidines/therapeutic use , Aged , C-Reactive Protein/analysis , Combined Modality Therapy/adverse effects , Deoxyglucose/blood , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/diet therapy , Diet, Diabetic , Dipeptidyl-Peptidase IV Inhibitors/adverse effects , Drug Resistance, Multiple , Drug Therapy, Combination/adverse effects , Female , Glycation End Products, Advanced , Humans , Hypoglycemia/chemically induced , Hypoglycemic Agents/adverse effects , Hypoglycemic Agents/therapeutic use , Insulin/adverse effects , Japan , Male , Middle Aged , Monitoring, Ambulatory , Pilot Projects , Prospective Studies , Pyrazoles/adverse effects , Serum Albumin/analysis , Thiazolidines/adverse effects , Glycated Serum Albumin
16.
Inorg Chem ; 53(5): 2481-90, 2014 Mar 03.
Article in English | MEDLINE | ID: mdl-24528148

ABSTRACT

This work involved a detailed investigation into the infrared vibrational spectra of ruthenium polypyridyl complexes, specifically heteroleptic [Ru(bpy)2(bpm)](2+) (bpy = 2,2'-bipyridine and bpm = 2,2'-bipyrimidine) and homoleptic [Ru(bpy)3](2+), in the excited triplet state. Transient spectra were acquired 500 ps after photoexcitation, corresponding to the vibrational ground state of the excited triplet state, using time-resolved infrared spectroscopy. We assigned the observed bands to specific ligands in [Ru(bpy)2(bpm)](2+) based on the results of deuterium substitution and identified the corresponding normal vibrational modes using quantum-chemical calculations. Through this process, the more complex vibrational bands of [Ru(bpy)3](2+) were assigned to normal vibrational modes. The results are in good agreement with the model in which excited electrons are localized on a single ligand. We also found that the vibrational bands of both complexes associated with the ligands on which electrons are little localized appear at approximately 1317 and 1608 cm(-1). These assignments should allow the study of the reaction dynamics of various photofunctional systems including ruthenium polypyridyl complexes.


Subject(s)
2,2'-Dipyridyl/analogs & derivatives , Coordination Complexes/chemistry , Models, Molecular , Organometallic Compounds/chemistry , Quantum Theory , Ruthenium/chemistry , Spectrophotometry, Infrared , 2,2'-Dipyridyl/chemistry , Molecular Structure , Vibration
17.
J Vet Med Sci ; 76(5): 719-22, 2014 May.
Article in English | MEDLINE | ID: mdl-24419873

ABSTRACT

In this study, the effect of cholinergic or adrenergic inhibitors on the reactivation of latent Pseudorabies virus (PRV) was analyzed to clarify the mechanism of the reactivation of latent PRV by acetylcholine. For acetylcholine inhibition, latently infected mice were injected with scopolamine or succynilcholine before acetylcholine stimulation. For sympathetic blocking, mice were preinjected intraperitoneally with phenoxybenzamine or propranolol. The signals to both acetylcholine receptors had no relationship to the reactivation of latent PRV, and both sympathetic blockers showed inhibition of PRV reactivation by acetylcholine. In our reactivation model, a large amount of acetylcholine may stimulate the sympathetic nerve system in some way to reactivate the virus.


Subject(s)
Acetylcholine/antagonists & inhibitors , Acetylcholine/pharmacology , Herpesvirus 1, Suid/physiology , Virus Activation/physiology , Virus Latency/physiology , Adrenergic Antagonists/pharmacology , Animals , Mice , Mice, Inbred BALB C , Scopolamine/pharmacology , Sympathetic Nervous System/drug effects , Sympathetic Nervous System/virology , Virus Activation/drug effects
18.
Int J Cardiol ; 156(1): 55-61, 2012 Apr 05.
Article in English | MEDLINE | ID: mdl-21093076

ABSTRACT

BACKGROUND: An HMG-CoA reductase inhibitor, fluvastatin, appears to act directly on the blood vessel wall to stabilize plaques in situ, agents that share this property have been termed vascular statins. METHODS: We investigated the effects of fluvastatin on endothelial nitric oxide synthase (eNOS) phosphorylation and expression, as well as terahydrobiopterin (BH4) metabolism, in human umbilical vein endothelial cells (HUVEC). RESULTS: Fluvastatin was observed to enhance eNOS phosphorylation at Ser-1177 and Ser-633 through the PI3-kinase/Akt and PKA pathways, respectively. Inhibition of eNOS phosphorylation using inhibitors of these pathways attenuated acute NO release in response to fluvastatin. The mRNA of GTP cyclohydrolase I (GTPCH), the rate-limiting enzyme of the first step of de novo BH4 synthesis, as well as eNOS, was upregulated in HUVEC treated with fluvastatin. In parallel with this observation, fluvastatin increased intracellular BH4. Pre-treatment of HUVEC with the selective GTPCH inhibitor, 2,4-diamino-6-hydroxypyrimidine, reduced intracellular BH4 and decreased citrulline formation following stimulation with ionomycin. Furthermore, the potentiating effect of fluvastatin was reduced by limiting the cellular availability of BH4. CONCLUSIONS: Our data demonstrate that fluvastatin phosphorylates and activates eNOS, and increases eNOS expression in vascular endothelial cells. In addition to modulating eNOS, fluvastatin potentiates GTPCH gene expression and BH4 synthesis, thereby increasing NO production and preventing relative shortages of BH4.


Subject(s)
Antioxidants/pharmacology , Biopterins/analogs & derivatives , Fatty Acids, Monounsaturated/pharmacology , Human Umbilical Vein Endothelial Cells/enzymology , Indoles/pharmacology , Nitric Oxide Synthase Type III/metabolism , Animals , Biopterins/metabolism , Cells, Cultured , Dose-Response Relationship, Drug , Endothelial Cells/drug effects , Endothelial Cells/enzymology , Enzyme Activation , Fluvastatin , Gene Expression Regulation , Human Umbilical Vein Endothelial Cells/drug effects , Humans , Mice , Phosphorylation , Up-Regulation
19.
J Chem Phys ; 134(8): 084311, 2011 Feb 28.
Article in English | MEDLINE | ID: mdl-21361543

ABSTRACT

We have determined the potential-energy function for the internal rotation of the methyl group for o- and m-ethynyltoluene in the electronic excited (S(1)) and ground (S(0)) states by measuring the fluorescence excitation and single-vibronic-level dispersed fluorescence spectra in a jet. The 0-0 bands were observed at 35 444 and 35 416 cm(-1), respectively. The methyl group in o-ethynyltoluene is shown to be a rigid rotor with a potential barrier to rotation of 190 ± 10 cm(-1) in both states. No change in the conformation occurred upon excitation. Barrier heights of m-ethynyltoluene in the S(0) and S(1) states are shown to be 19 ± 3 and 101 ± 1 cm(-1), respectively. A conformational change occurred with rotation by 60[ordinal indicator, masculine] upon excitation. The potential parameters were as follows: reduced rotational constant (B) of 5.323 cm(-1), centrifugal-distortion constant (D) of 6.481 × 10(-5) cm(-1), V(3) = 19 cm(-1), V(6) = -6 cm(-1), and V(9) = 0 cm(-1) in the S(0) state, and B = 5.015 cm(-1), D = 5.392 × 10(-5) cm(-1), V(3) = 101 cm(-1), V(6) = -22 cm(-1), and V(9) = -2 cm(-1) in the S(1) state. For m-methylstyrene, m-tolunitrile, and m-ethynyltoluene, which all have a multiple-bonded carbon in the substituent, we found a new correlation between the Hammett substituent constant σ(m) and the change in the barrier of the methyl group upon excitation.

20.
Endocr J ; 58(3): 171-5, 2011.
Article in English | MEDLINE | ID: mdl-21304215

ABSTRACT

It is well established that statins improve the prognosis of patients with coronary artery disease. However, it is still unclear whether the protective effects of statins relate to lipid lowering alone or whether other pleiotropic effects may contribute. Thus, we compared the endothelial function among two groups of diabetic patients treated with fluvastatin 60 mg (F60) or fluvastatin 20 mg combined with ezetimibe 10 mg (F20/E10). The endothelial function was evaluated by measuring flow-mediated vasodilatation (FMD) at baseline and follow-up at 10 weeks. Similar improvements in FMD were observed in the two groups. The reduction in low-density lipoprotein cholesterol (LDL-C) was less pronounced in the F60 group, compared with the F20/E10 group. A significant reduction in remnant-like lipoprotein particles cholesterol (RLP-C) was observed in the F20/E10 group, but not in the F60 group. A correlation between the observed reduction in LDL-C or RLP-C and the improvement in FMD was observed in F20/E10 group. These results suggest that high-dose fluvastatin might have pleiotropic effects of potential clinical benefit, and that the combination of ezetimibe with a reduced dose of fluvastatin may also significantly improve endothelial function with reduction of LDL-C and RLP-C.


Subject(s)
Anticholesteremic Agents/pharmacology , Azetidines/pharmacology , Diabetes Mellitus/physiopathology , Endothelium, Vascular/drug effects , Endothelium, Vascular/physiopathology , Fatty Acids, Monounsaturated/pharmacology , Indoles/pharmacology , Aged , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Diabetes Mellitus/blood , Dose-Response Relationship, Drug , Drug Therapy, Combination , Ezetimibe , Female , Fluvastatin , Humans , Male , Middle Aged , Treatment Outcome , Triglycerides/blood , Vasodilation/drug effects , Vasodilation/physiology
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