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1.
Sensors (Basel) ; 24(9)2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38733048

RESUMEN

This study proposes an optimization method for temperature modulation in chemiresistor-type gas sensors based on Bayesian optimization (BO), and its applicability was investigated. As voltage for a sensor heater, our previously proposed waveform was employed, and the parameters determining the voltage range were optimized. Employing the Bouldin-Davies index (DBI) as an objective function (OBJ), BO was utilized to minimize the DBI calculated from a feature matrix built from the collected data followed by pre-processing. The sensor responses were measured using five test gases with five concentrations, amounting to 2500 data points per parameter set. After seven trials with four initial parameter sets (ten parameter sets were tested in total), the DBI was successfully reduced from 2.1 to 1.5. The classification accuracy for the test gases based on the support vector machine tends to increase with decreasing the DBI, indicating that the DBI acts as a good OBJ. Additionally, the accuracy itself increased from 85.4% to 93.2% through optimization. The deviation from the tendency that the accuracy increases with decreasing the DBI for some parameter sets was also discussed. Consequently, it was demonstrated that the proposed optimization method based on BO is promising for temperature modulation.

2.
Biochemistry ; 60(43): 3253-3261, 2021 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-34658241

RESUMEN

Photolyases (PHRs) repair ultraviolet (UV)-induced DNA photoproducts into normal bases. In this study, we measured the conformational changes upon photoactivation and photorepair processes of a PHR and its specific substrates, (6-4)PHR and a pyrimidine(6-4)pyrimidone photoproduct ((6-4)PP), by light-induced difference Fourier transform infrared (FT-IR) spectroscopy. The single-stranded DNA with (6-4)PP (ss(6-4)PP) was used as a substrate and the resultant FT-IR spectra were compared with the previous results on double-stranded DNA with (6-4)PP (ds(6-4)PP). In the excess amount of substrate to the enzyme, different ss(6-4)PP photorepair FT-IR signals were obtained in an illumination time-dependent manner. As reported for ds(6-4)PP, the early stages of the photoreaction involve the changes in the ss(6-4)PP only, while the late stages of the reaction involve the ss(6-4)PP repair-associated changes and dissociation from (6-4)PHR. From these spectra, difference spectra originating from the binding/dissociation spectrum were extracted. The signals of the C═O stretches of (6-4)PP and repaired thymines in the single- and double-stranded DNA were tentatively assigned. The C═O stretches of (6-4)PP were observed at frequencies that reflect single- and double-stranded DNA environments in aqueous solution, reflecting the different hydrogen-bonding environments. The conformational changes of PHR upon binding of ss(6-4)PP and ds(6-4)PP were similar, suggesting that the conformational change is limited to the (6-4)PP binding pocket region. We interpreted that ds(6-4)PP may be bound together without any special mechanism for flipping out.


Asunto(s)
Reparación del ADN/fisiología , Desoxirribodipirimidina Fotoliasa/metabolismo , Animales , ADN/metabolismo , Roturas del ADN de Doble Cadena , ADN de Cadena Simple/química , ADN de Cadena Simple/metabolismo , Pirimidinas , Pirimidinonas , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Rayos Ultravioleta/efectos adversos , Proteínas de Xenopus/metabolismo , Xenopus laevis/metabolismo
3.
Adv Exp Med Biol ; 1293: 189-206, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33398814

RESUMEN

Three classes of flavoprotein photoreceptors, cryptochromes (CRYs), light-oxygen-voltage (LOV)-domain proteins, and blue light using FAD (BLUF)-domain proteins, have been identified that control various physiological processes in multiple organisms. Accordingly, signaling activities of photoreceptors have been intensively studied and the related mechanisms have been exploited in numerous optogenetic tools. Herein, we summarize the current understanding of photoactivation mechanisms of the flavoprotein photoreceptors and review their applications.


Asunto(s)
Flavoproteínas/metabolismo , Flavoproteínas/efectos de la radiación , Fototransducción/efectos de la radiación , Luz , Optogenética , Criptocromos/genética , Criptocromos/metabolismo , Criptocromos/efectos de la radiación , Flavoproteínas/genética
4.
Sensors (Basel) ; 21(22)2021 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-34833757

RESUMEN

Towards clarifying the spatio-temporal neurotransmitter distribution, potentiometric redox sensor arrays with 23.5-µm resolution were fabricated. The sensor array based on a charge-transfer-type potentiometric sensor comprises 128×128 pixels with gold electrodes deposited on the surface of pixels. The sensor output corresponding to the interfacial potential of the electrode changed logarithmically with the mixture ratio of K3Fe(CN)6 and K4Fe(CN)6, where the redox sensitivity reached 49.9 mV/dec. By employing hydrogen peroxidase as an enzyme and ferrocene as an electron mediator, the sensing characteristics for hydrogen peroxide (H2O2) were investigated. The analyses of the sensing characteristics revealed that the sensitivity was about 44.7 mV/dec., comparable to the redox sensitivity, while the limit of detection (LOD) was achieved to be 1 µM. Furthermore, the oxidation state of the electron mediator can be the key to further lowering the LOD. Then, by immobilizing oxidizing enzyme for H2O2 and glutamate oxidase, glutamate (Glu) measurements were conducted. As a result, similar sensitivity and LOD to those of H2O2 were obtained. Finally, the real-time distribution of 1 µM Glu was visualized, demonstrating the feasibility of our device as a high-resolution bioimaging technique.


Asunto(s)
Técnicas Biosensibles , Peróxido de Hidrógeno , Electrodos , Ácido Glutámico , Oro , Oxidación-Reducción , Potenciometría
5.
Photochem Photobiol Sci ; 19(10): 1326-1331, 2020 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-32935701

RESUMEN

Cryptochromes (CRYs) are blue-light receptors involved in photomorphogenesis in plants. Flavin adenine dinucleotide (FAD) is one of the chromophores of cryptochromes; its resting state oxidized form is converted into a signalling state neutral semiquionod radical (FADH˙) form. Studies have shown that cryptochrome 1 from Arabidopsis thaliana (AtCRY1) can bind ATP at its photolyase homology region (PHR), resulting in accumulation of FADH˙ form. This study used light-induced difference Fourier transform infrared spectroscopy to investigate how ATP influences structural changes in AtCRY1-PHR during the photoreaction. In the presence of ATP, there were large changes in the signals from the protein backbone compared with in the absence of ATP. The deprotonation of a carboxylic acid was observed only in the presence of ATP; this was assigned as aspartic acid (Asp) 396 through measurement of Asp to glutamic acid mutants. This corresponds to the protonation state of Asp396 estimated from the reported pKa values of Asp396; that is, the side chain of Asp396 is deprotonated and protonated for the ATP-free and -bound forms, respectively, in our experimental condition at pH8. Therefore, Asp396 acts a proton donor to FAD when it is ptotonated. It was indicated that the protonation/deprotination process of Asp396 is correlated with the accunumulation of FADH˙ and protein conformational changes.


Asunto(s)
Adenosina Trifosfato/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/química , Ácido Aspártico/metabolismo , Criptocromos/metabolismo , Luz , Adenosina Trifosfato/química , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Ácido Aspártico/química , Criptocromos/química , Concentración de Iones de Hidrógeno , Modelos Moleculares
6.
J Am Chem Soc ; 140(38): 11982-11991, 2018 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-30168326

RESUMEN

Three kinds of photochemical reactions are known in flavins as chromophores of photosensor proteins, reflecting the various catalytic reactions of the flavin in flavoenzymes. Sensor of blue light using the flavin FAD (BLUF) domains exhibit a unique photoreaction compared with other flavin-binding photoreceptors in that the chromophore does not change its chemical structure between unphotolyzed and intermediate states. Rather, the hydrogen bonding environment is altered, whereby the conserved Gln and Tyr residues near FAD play a crucial role. One proposal for this behavior is that the conserved Gln changes its chemical structure from a keto to an enol. We applied light-induced difference Fourier transform infrared (FTIR) spectroscopy to AppA-BLUF. The spectra of AppA-BLUF exhibited a different feature upon 15N-Gln labeling compared with the previously reported spectra from BlrB, a different BLUF domain. The FTIR signals were interpreted from quantum mechanics/molecular mechanics (QM/MM) calculation as the keto-enol tautomerization and rotation of the Gln63 side chain in the AppA-BLUF domain. The former was consistent with the result from BlrB, but the latter was not uniquely determined by the previous study. QM/MM calculation also indicated that the infrared signal shape is influenced depending on whether a Trp side chain forms a hydrogen bond with the Gln side chain. FTIR spectra and QM/MM simulations concluded that Trp104 does not flip out but is maintained in the intermediate state. In contrast, our data revealed that the Trp residue at the corresponding position in BlrB faces outward in both states.

7.
Biochemistry ; 56(24): 3099-3108, 2017 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-28530801

RESUMEN

The light oxygen voltage (LOV) domain is a flavin-binding blue-light receptor domain, originally found in a plant photoreceptor phototropin (phot). Recently, LOV domains have been used in optogenetics as the photosensory domain of fusion proteins. Therefore, it is important to understand how LOV domains exhibit light-induced structural changes for the kinase domain regulation, which enables the design of LOV-containing optogenetics tools with higher photoactivation efficiency. In this study, the hydrogen bonding environment of the N3-H group of flavin mononucleotide (FMN) of the LOV2 domain from Adiantum neochrome (neo) 1 was investigated by low-temperature Fourier transform infrared spectroscopy. Using specifically 15N-labeled FMN, [1,3-15N2]FMN, the N3-H stretch was identified at 2831 cm-1 for the unphotolyzed state at 150 K, indicating that the N3-H group forms a fairly strong hydrogen bond. The N3-H stretch showed temperature dependence, with a shift to lower frequencies at ≤200 K and to higher frequencies at ≥250 K from the unphotolyzed to the intermediate states. Similar trends were observed in the LOV2 domains from Arabidopsis phot1 and phot2. By contrast, the N3-H stretch of the Q1029L mutant of neo1-LOV2 and neo1-LOV1 was not temperature dependent in the intermediate state. These results seemed correlated with our previous finding that the LOV2 domains show the structural changes in the ß-sheet region and/or the adjacent Jα helix of LOV2 domain, but that such structural changes do not take place in the Q1029L mutant or neo1-LOV1 domain. The environment around the N3-H group was also investigated.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Proteínas de Unión al ADN/metabolismo , Mononucleótido de Flavina/química , Mononucleótido de Flavina/metabolismo , Fototropinas/química , Fototropinas/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Unión al ADN/química , Enlace de Hidrógeno
8.
Sensors (Basel) ; 17(9)2017 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-28930146

RESUMEN

Demand for the detection of carbon dioxide (CO 2 ) is increasing in various fields, including air-quality monitoring, healthcare, and agriculture. On the other hand, smart gas sensors, in which micromachined gas sensors are integrated with driving circuits, are desirable toward the development of the society of the internet of things. In this study, micromachined hotplate-based CO 2 sensors were fabricated and their characteristics were investigated. The sensors have La 2 O 3 /SnO 2 stacked layers as a sensing material and Pt interdigitated electrodes. A CO 2 response of 2.9 for a CO 2 concentration of 1000 ppm was obtained at 350 °C with low power consumption (approximately 17 mW). A relatively large response was obtained compared with previous studies even though a compact sputtered-SnO 2 film was used. This high response was speculated to be due to a significant contribution of the resistance component near the electrode. Furthermore, CO 2 sensing was successfully performed in the CO 2 range of 200-4000 ppm with at least 200-ppm resolution.

9.
Biochemistry ; 55(4): 715-23, 2016 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-26719910

RESUMEN

Photolyases (PHRs) repair the UV-induced photoproducts, cyclobutane pyrimidine dimer (CPD) or pyrimidine-pyrimidone (6-4) photoproduct [(6-4) PP], restoring normal bases to maintain genetic integrity. CPD and (6-4) PP are repaired by substrate-specific PHRs, CPD PHR and (6-4) PHR, respectively. Flavin adenine dinucleotide (FAD) is the chromophore of both PHRs, and the resting oxidized form (FAD(ox)), at least under in vitro purified conditions, is first photoconverted to the neutral semiquinoid radical (FADH(•)) form, followed by photoconversion into the enzymatically active fully reduced (FADH(-)) form. Previously, we reported light-induced difference Fourier transform infrared (FTIR) spectra corresponding to the photoactivation process of Xenopus (6-4) PHR. Spectral differences between the absence and presence of (6-4) PP were observed in the photoactivation process. To identify the FTIR signals where these differences appeared, we compared the FTIR spectra of photoactivation (i) in the presence and absence of (6-4) PP, (ii) of (13)C labeling, (15)N labeling, and [(14)N]His/(15)N labeling, and (iii) of H354A and H358A mutants. We successfully assigned the vibrational bands for (6-4) PP, the α-helix and neutral His residue(s). In particular, we assigned three bands to the C ═ O groups of (6-4) PP in the three different redox states of FAD. Furthermore, the changed hydrogen bonding environments of C ═ O groups of (6-4) PP suggested restructuring of the binding pocket of the DNA lesion in the process of photoactivation.


Asunto(s)
Desoxirribodipirimidina Fotoliasa/química , Flavina-Adenina Dinucleótido/química , Dímeros de Pirimidina/química , Proteínas de Xenopus/química , Sustitución de Aminoácidos , Animales , Dominio Catalítico , Desoxirribodipirimidina Fotoliasa/genética , Desoxirribodipirimidina Fotoliasa/metabolismo , Flavina-Adenina Dinucleótido/genética , Flavina-Adenina Dinucleótido/metabolismo , Mutación Missense , Dímeros de Pirimidina/genética , Dímeros de Pirimidina/metabolismo , Proteínas de Xenopus/genética , Proteínas de Xenopus/inmunología , Xenopus laevis
10.
Biochemistry ; 55(30): 4173-83, 2016 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-27431478

RESUMEN

Ultraviolet (UV) light from the sun damages DNA by forming a cyclobutane pyrimidine dimer (CPD) and pyrimidine(6-4)pyrimidone photoproducts [(6-4) PP]. Photolyase (PHR) enzymes utilize near-UV/blue light for DNA repair, which is initiated by light-induced electron transfer from the fully reduced flavin adenine dinucleotide chromophore. Despite similar structures and repair mechanisms, the functions of PHR are highly selective; CPD PHR repairs CPD, but not (6-4) PP, and vice versa. In this study, we attempted functional conversion between CPD and (6-4) PHRs. We found that a triple mutant of (6-4) PHR is able to repair the CPD photoproduct, though the repair efficiency is 1 order of magnitude lower than that of wild-type CPD PHR. Difference Fourier transform infrared spectra for repair demonstrate the lack of secondary structural alteration in the mutant, suggesting that the triple mutant gains substrate binding ability while it does not gain the optimized conformational changes from light-induced electron transfer to the release of the repaired DNA. Interestingly, the (6-4) photoproduct is not repaired by the reverse mutation of CPD PHR, and eight additional mutations (total of 11 mutations) introduced into CPD PHR are not sufficient. The observed asymmetric functional conversion is interpreted in terms of a more complex repair mechanism for (6-4) repair, which was supported by quantum chemical/molecular mechanical calculation. These results suggest that CPD PHR may represent an evolutionary origin for photolyase family proteins.


Asunto(s)
Desoxirribodipirimidina Fotoliasa/genética , Desoxirribodipirimidina Fotoliasa/metabolismo , Dímeros de Pirimidina/metabolismo , Sustitución de Aminoácidos , Animales , Dominio Catalítico/genética , Cristalografía por Rayos X , Daño del ADN , Reparación del ADN , Desoxirribodipirimidina Fotoliasa/química , Transporte de Electrón , Modelos Moleculares , Simulación de Dinámica Molecular , Mutagénesis Sitio-Dirigida , Conformación Proteica , Dímeros de Pirimidina/química , Dímeros de Pirimidina/efectos de la radiación , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Rayos Ultravioleta , Xenopus laevis
11.
J Am Chem Soc ; 138(13): 4368-76, 2016 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-27002596

RESUMEN

The spread of the absorbance of the stable FADH(•) radical (300-700 nm) allows CPD photolyase to highly efficiently form FADH(-), making it functional for DNA repair. In this study, FTIR spectroscopy detected a strong hydrogen bond, from FAD N5-H to the carbonyl group of the Asn378 side chain, that is modulated by the redox state of FAD. The observed characteristic frequency shifts were reproduced in quantum-mechanical models of the flavin binding site, which were then employed to elucidate redox tuning governed by Asn378. We demonstrate that enhanced hydrogen bonding of the Asn378 side chain with the FADH(•) radical increases thermodynamic stabilization of the radical state, and further ensures kinetic stabilization and accumulation of the fully reduced FADH(-) state.


Asunto(s)
Asparagina/metabolismo , Desoxirribodipirimidina Fotoliasa/metabolismo , Flavina-Adenina Dinucleótido/metabolismo , Flavinas/metabolismo , Asparagina/química , Sitios de Unión , Bisfenol A Glicidil Metacrilato , Reparación del ADN , Escherichia coli/enzimología , Flavina-Adenina Dinucleótido/química , Hidrógeno , Enlace de Hidrógeno , Cinética , Modelos Químicos , Conformación Molecular , Estructura Molecular , Oxidación-Reducción , Espectroscopía Infrarroja por Transformada de Fourier
12.
J Am Chem Soc ; 138(43): 14170-14173, 2016 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-27775341

RESUMEN

The polarization switching mechanism is used in various devices such as pyroelectric sensors and memory devices. The change in polarization mostly occurs by ion displacement. The development of materials whose polarization switches via electron transfer in order to enhance operation speed is a challenge. We devised a synthetic and crystal engineering strategy that enables the selective synthesis of a [CrCo] heterometallic dinuclear complex with a polar crystal structure, wherein polarization changes stem from intramolecular charge transfer between Co and the ligand. Polarization can be modulated both by visible-light irradiation and temperature change. The introduction of chiral ligands was paramount to the successful polarization switching in the valence tautomeric compound. Mixing Cr and Co complexes with enantiopure chiral ligands resulted in the selective formation of only pseudosymmetric [CrCo] heterometallic complexes. Furthermore, the left-handed chiral ligands preferentially interacted with their right-handed counterparts, enabling molecules to form a polar crystal structure.

13.
Hinyokika Kiyo ; 62(2): 73-6, 2016 Feb.
Artículo en Japonés | MEDLINE | ID: mdl-27018409

RESUMEN

An 81-year-old man was referred to our hospital because of a right renal tumor with vena cava thrombus and multiple lung metastases that were detected by computed tomography (CT) scan during evaluation of respiratory discomfort. We started medical treatment with sunitinib at a dose of 50 mg daily in a 2-week-on, 1-week-off schedule after confirming clear cell renal cell carcinoma by tumor biopsy. After 2-week sunitinib treatment, thrombocytopenia continued and platelet count decreased to 1.8×10(9)/l at day 11 after stopping sunitinib. We needed to administer a total of 60 units platelet transfusion because of persistent thrombocytopenia. Bone marrow aspiration did not reveal myelosuppression or carcinoma invasion to bone marrow. Under the clinical diagnosis of drug-induced thrombocytopenia secondary to sunitinib, we started immunoglobulin therapy at day 23 after stopping sunitinib. Platelet count returned to normal 10 days after starting immunoglobulin. The patient developed exacerbating lung metastasis and carcinomatous lymphangiosis during subsequent course and died of renal cell carcinoma 79 days after starting sunitinib. Thrombocytopenia after sunitinib therapy is often encountered but prolonged thrombocytopenia is rare after stopping sunitinib. This case suggests that immunoglobulin therapy is effective for drug-induced prolonged thrombocytopenia through immunological mechanism.


Asunto(s)
Antineoplásicos/efectos adversos , Carcinoma de Células Renales/tratamiento farmacológico , Inmunoglobulinas/uso terapéutico , Indoles/efectos adversos , Neoplasias Renales/tratamiento farmacológico , Pirroles/efectos adversos , Trombocitopenia/tratamiento farmacológico , Anciano de 80 o más Años , Antineoplásicos/uso terapéutico , Biopsia , Humanos , Indoles/uso terapéutico , Neoplasias Renales/patología , Masculino , Pirroles/uso terapéutico , Sunitinib , Trombocitopenia/inducido químicamente
14.
Hinyokika Kiyo ; 62(1): 25-8, 2016 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-26932332

RESUMEN

A 66-year-old male patient was referred to our hospital for bilateral renal pelvic tumors. Ureteroscopic biopsy revealed urothelial carcinoma (UC) of low grade (G1) of the renal pelvis. Renal sparing treatment with systemic chemotherapy and percutaneous tumor resection was performed. However, during subsequent follow up, a recurrent tumor was found on the left ureter. After ureteroscopic laser ablation of the tumor, Bacillus Calmette-Guerin (BCG) perfusion therapy (once a week, total 6 weeks) was performed via a single J ureteral catheter with no adverse events. Later, another recurrent recurrence was found on the right ureter, and was managed by ureteroscopic laser ablation followed by BCG perfusion therapy via a single J ureteral catheter. However, the patient developed high fever with chill from the day after initial BCG perfusion therapy on the right side. Although we started antibiotics, high fever continued. Then antituberculous drugs were administered and his condition was improved. Computed tomographic scan revealed a right renal mass 57 mm in diameter, which was consistent with tuberculous granuloma. The tuberculous granuloma persisted despite the continuation of anti-tuberculous drugs. In exceptional cases of upper tract UC such as single kidney and bilateral tumor, BCG perfusion therapy has been used as adjunctive treatment to cure or prevent UC. However, dosages and administration methods of BCG perfusion therapy for upper tract UC still remain to be standardized. Serious adverse events after BCG perfusion therapy require prompt and proper management including the use of anti-tuberculous drugs.


Asunto(s)
Vacuna BCG/uso terapéutico , Granuloma , Neoplasias Renales/patología , Pelvis/patología , Tuberculosis , Granuloma/patología , Granuloma/cirugía , Humanos , Neoplasias Renales/cirugía , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Nefrectomía
15.
Gan To Kagaku Ryoho ; 43(6): 727-31, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27306809

RESUMEN

OBJECTIVES: To investigate the efficacy of combination treatment of degarelix and antiandrogen in patients with prostate cancer. METHODS: We prospectively investigated the efficacy of combination treatment of degarelix and antiandrogen in 12 patients with treatment-naive prostate cancer. We surveyed PSA, LH, FSH and testosterone at day 3, 7, 14 and 28 during the initial month and thereafter once a month for 1 year. In cases with bone metastasis, we analyzed serum bone markers such as alkaline phosphatase(ALP), bone-type ALP and carboxyterminal telopeptide of type- I collagen once a month. Skeletal related events (SREs) were also monitored. RESULTS: PSA progression free survival was 65%. PSA was reduced from baseline by 80% at day 14 and by 93% at day 28. In all patients serum testosterone immediately reached castrate level at day 3 and was maintained for 1 year without breakthrough escape. Both LH and FSH were reduced to within normal range at day 3. In contrast, all bone markers temporarily increased at day 28, and thereafter decreased. Although 2 patients had suffered from SREs before treatment, there were no SREs after combination treatment. CONCLUSIONS: The present study showed that combination of degarelix and antiandrogen could lead to favorable PSA reduction and immediate castrate level at an earlier phase. However, further study is needed to compare the difference between degarelix monotherapy and these combinations.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Óseas/secundario , Neoplasias de la Próstata/tratamiento farmacológico , Anciano , Antagonistas de Andrógenos/administración & dosificación , Estudios de Cohortes , Humanos , Masculino , Persona de Mediana Edad , Oligopéptidos/administración & dosificación , Estudios Prospectivos , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/patología
16.
Biochemistry ; 53(37): 5864-75, 2014 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-25152314

RESUMEN

Observations of light-receptive enzyme complexes are usually complicated by simultaneous overlapping signals from the chromophore, apoprotein, and substrate, so that only the initial, ultrafast, photon-chromophore reaction and the final, slow, protein conformational change provide separate, nonoverlapping signals. Each provides its own advantages, whereas sometimes the overlapping signals from the intervening time scales still cannot be fully deconvoluted. We overcome the problem by using a novel method to selectively isotope-label the apoprotein but not the flavin adenine dinucleotide (FAD) cofactor. This allowed the Fourier transform infrared (FTIR) signals to be separated from the apoprotein, FAD cofactor, and DNA substrate. Consequently, a comprehensive structure-function study by FTIR spectroscopy of the Escherichia coli cyclobutane pyrimidine dimer photolyase (CPD-PHR) DNA repair enzyme was possible. FTIR signals could be identified and assigned upon FAD photoactivation and DNA repair, which revealed protein dynamics for both processes beyond simple one-electron reduction and ejection, respectively. The FTIR data suggest that the synergistic cofactor-protein partnership in CPD-PHR linked to changes in the shape of FAD upon one-electron reduction may be coordinated with conformational changes in the apoprotein, allowing it to fit the DNA substrate. Activation of the CPD-PHR chromophore primes the apoprotein for subsequent DNA repair, suggesting that CPD-PHR is not simply an electron-ejecting structure. When FAD is activated, changes in its structure may trigger coordinated conformational changes in the apoprotein and thymine carbonyl of the substrate, highlighting the role of Glu275. In contrast, during DNA repair and release processes, primary conformational changes occur in the enzyme and DNA substrate, with little contribution from the FAD cofactor and surrounding amino acid residues.


Asunto(s)
Desoxirribodipirimidina Fotoliasa/química , Flavina-Adenina Dinucleótido/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Sitios de Unión , Isótopos de Carbono , Reparación del ADN , Desoxirribodipirimidina Fotoliasa/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Marcaje Isotópico , Luz , Estructura Secundaria de Proteína , Dímeros de Pirimidina/química , Relación Estructura-Actividad
17.
J Am Chem Soc ; 136(9): 3475-82, 2014 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-24512107

RESUMEN

Channelrhodopsin (ChR) functions as a light-gated ion channel in Chlamydomonas reinhardtii. Passive transport of cations by ChR is fundamentally different from the active transport by light-driven ion pumps such as archaerhodopsin, bacteriorhodopsin, and halorhodopsin. These microbial rhodopsins are important tools for optogenetics, where ChR is used to activate neurons by light, while the ion pumps are used for neural silencing. Ion-transport functions by these rhodopsins strongly depend on the specific hydrogen-bonding networks containing water near the retinal chromophore. In this work, we measured protein-bound water molecules in a chimeric ChR protein of ChR1 (helices A to E) and ChR2 (helices F and G) of Chlamydomonas reinhardtii using low-temperature FTIR spectroscopy at 77 K. We found that the active center of ChR possesses more water molecules (9 water vibrations) than those of other microbial (2-6 water vibrations) and animal (6-8 water vibrations) rhodopsins. We conclude that the protonated retinal Schiff base interacts with the counterion (Glu162) directly, without the intervening water molecule found in proton-pumping microbial rhodopsins. The present FTIR results and the recent X-ray structure of ChR reveal a unique hydrogen-bonding network around the active center of this light-gated ion channel.


Asunto(s)
Bacteriorodopsinas/química , Agua/química , Bacteriorodopsinas/genética , Bacteriorodopsinas/metabolismo , Chlamydomonas reinhardtii , Enlace de Hidrógeno , Isomerismo , Modelos Moleculares , Mutación , Procesos Fotoquímicos , Estructura Secundaria de Proteína , Temperatura , Vibración
18.
Hinyokika Kiyo ; 60(11): 531-5, 2014 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-25511938

RESUMEN

We examined perioperative complications of transurethral resection of bladder tumor (TURBT) in patients receiving antithrombotic therapy. We retrospectively studied 276 patients who underwent TURBT in our institute from January 2007 to March 2013. The study group consisted of 105 patients (38%) who were receiving antithrombotic agents, and the other 171 patients (62%) without antithrombotic agents were assigned to the control group. The period of discontinuation of antithrombotic agents complied with our institutional rule. The most frequently used agent was aspirin (69 patients : 66%), followed by warfarin (25 patients : 24%). Fourteen patients receiving warfarin (56%) needed heparin bridging therapy. There was no significant difference in average operative time (51 minutes versus 54 minutes), or average days to removal of urethral catheter (3.7 days versus 3.3 days) between the study and control groups. Hemorrhagic and ischemic complications were noted in 11 (10.5%) and 2 (1.9%) patients in the study group and 11 (6.4%) and none (0%) of the patients in the control group, respectively, with no significant difference between the 2 groups. However, prevalence of hemorrhagic complications in patients receiving heparin bridging therapy (21.4%) was significantly higher than that in the control group. Ischemic complications in the study group included chest pain suggestive of angina in one patient and acute myocardial infarction leading to death in another patient. We should pay attention to hemorrhagic complications in patients receiving heparin bridging therapy and keep in mind the possibility of lethal ischemic complications after discontinuation of antithrombotic agents.


Asunto(s)
Angina de Pecho/etiología , Fibrinolíticos/efectos adversos , Hemorragia/etiología , Infarto del Miocardio/etiología , Complicaciones Posoperatorias , Neoplasias de la Vejiga Urinaria/cirugía , Anciano , Anciano de 80 o más Años , Angina de Pecho/epidemiología , Aspirina/administración & dosificación , Aspirina/efectos adversos , Cistectomía/métodos , Femenino , Fibrinolíticos/administración & dosificación , Hemorragia/epidemiología , Heparina/administración & dosificación , Heparina/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/epidemiología , Estudios Retrospectivos , Uretra , Warfarina/administración & dosificación , Warfarina/efectos adversos
19.
Hinyokika Kiyo ; 60(3): 121-3, 2014 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-24759497

RESUMEN

An 11-year-old girl visited the emergency room of our hospital with complaints of pain, nausea and gross hematuria after abdominal injury due to a fall from a fence. Computed tomography (CT) showed ruptured right kidney, hematoma, urinoma, and slight liver damage in S7 area. According to the Classification of Renal Injury by the Japanese Association for the Surgery of Trauma, this case was Type IIIb, but according to the American Association for the Surgery of Trauma Organ Injury Severity Scale for the Kidney, it was Type V. Because her vital signs were stable after admission, conservative management was initiated. There was no progression of anemia, and blood transfusion was not required. Right ureteral stenting was performed on the 4th hospital day because of an increase in fluid accumulation around the right kidney. Percutaneous drainage was performed on the 9th hospital day because of a further increase in fluid accumulation around the right kidney. After percutaneous drainage, fluid accumulation around the kidney was improved, and the drainage tube was removed on the 20th hospital day. The patient was discharged on the 22nd day. Although the decreased blood flow in the ruptured portion of the right kidney was observed in a subsequent CT scan, renal scintigraphy showed a relatively well maintained function of the right kidney (split renal function; right 38% and left 62%). She had no increase in blood pressure one year after renal injury.


Asunto(s)
Riñón/lesiones , Accidentes por Caídas , Niño , Drenaje , Femenino , Humanos , Rotura
20.
Stud Health Technol Inform ; 310: 1400-1401, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38269666

RESUMEN

In Japan, oversights of imaging or pathology examination results and diagnoses provided to patients have become a major problem because they affect patient prognosis. We have jointly developed and used the "Anti-Impact Information Leakage Prevention System (AiR)" since December 2019. This system works effectively because its introduction, which uses a data warehouse, has increased versatility and considerably improved the situation of confirmation and communication. We believe this system is working effectively.


Asunto(s)
Comunicación , Data Warehousing , Humanos , Japón
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