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This paper proposes a new optical biosensor composed of a silicon-on-insulator (SOI) p-n junction photodiode (PD) with a surface plasmon (SP) antenna. When the phase-matching condition between two lateral wavelengths of the diffracted light from the SP antenna and the waveguiding mode in the SOI PD is satisfied, we observe sharp peaks in the spectroscopic light sensitivity. Since the peak wavelength depends on the RI change around the SP antenna corresponding to the phase-matching condition, the SOI PDs with an SP antenna can be applied to the optical biosensor. The RI detection limit is evaluated in the measurements with bulk solutions, and 1.11 × 10-5 RIU (refractive index unit) can be obtained, which is comparable to that of a surface plasmon resonance (SPR) sensor, which is well known as a representative optical biosensor. In addition, the response for intermolecular bonds is estimated by the electromagnetic simulations using the finite-difference time-domain (FDTD) method to clarify its ability to detect biomolecular interactions. The results of this paper will provide new ground for high-throughput label-free biosensing, since a large number of SOI PDs with an SP antenna can be easily integrated on a single chip via an SOI complementary metal-oxide-semiconductor (CMOS) fabrication process.
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Técnicas Biossensoriais , Silício , Silício/química , Refratometria , Ressonância de Plasmônio de Superfície , Dióxido de SilícioRESUMO
A 70-year-old patient who survived about 40 years after left pneumonectomy for tuberculosis visited emergency hospital, because of dyspnea. She received suitable medical therapy for atirial fibrillation and severe mitral regurgitation and hesitated heart surgery because of anxiety for surgical risk. The computed-tomography showed mediastinal shift to left and right lung compensatory expansion. Respiratory function test after treatment of heart failure showed only mild restrictive disorder. And the blood-gas examination in room air was 101 mmHg of Pao2 and 37 mmHg of Paco2. The mitral valve replacement was performed via median sternotomy and using normal cardiopulmonary bypass. And she fully recoverd without any respiratory complications. Mediastinal shift did not obstract the surgical view and establishment of cardiopulmonary bypass in this case. It seemed that the key of surgical successs is the preserved function of healthy residual lung.
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Procedimentos Cirúrgicos Cardíacos , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Idoso , Ponte Cardiopulmonar , Feminino , Humanos , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia , PneumonectomiaRESUMO
We demonstrate sub-micrometer processing of two kinds of thin films, polymethyl methacrylate (PMMA) and metal nano-particle resist, by focusing high-order harmonics of near-IR femtosecond laser pulses in the extreme ultraviolet (XUV) wavelength region (27.2-34.3 nm) on the thin film samples using an ellipsoidal focusing mirror. The ablation threshold fluences for the PMMA sample and the metal nano-particle resist per XUV pulse obtained by the accumulation of 200 XUV pulses were determined to be 0.42mJ/cm2 and 0.17mJ/cm2, respectively. The diameters (FWHM) of a hole created by the ablation on the PMMA film at the focus were 0.67 µm and 0.44 µm along the horizontal direction and the vertical direction, respectively. The fluence dependence of the Raman microscope spectra of the processed holes on the PMMA sample showed that the chemical modification, in which C=C double bonds are formed associated with the scission of the PMMA polymer chains, is achieved by the irradiation of the XUV pulses.
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BACKGROUND: Patient safety culture is defined as a product of individual and group values, attitudes, perceptions, competencies, and patterns of behavior that determine the commitment to, and the style and proficiency of, an organization's health and safety management. Factors influencing healthcare workers' working environment such as working hours, the number of night shifts, and the number of days off may be associated with patient safety culture, and the association pattern may differ by profession. This study aimed to examine the relationship between patient safety culture and working environment. METHODS: Questionnaire surveys were conducted in 2015 and 2016. The first survey was conducted in hospitals in Japan to investigate their patient safety management system and activities and intention to participate in the second survey. The second survey was conducted in 40 hospitals; 100 healthcare workers from each hospital answered a questionnaire that was the Japanese version of the Hospital Survey on Patient Safety Culture for measuring patient safety culture. The relationship of patient safety culture with working hours in a week, the number of night shifts in a month, and the number of days off in a month was analyzed. RESULTS: Response rates for the first and second surveys were 22.4% (731/3270) and 94.2% (3768/4000), respectively. Long working hours, numerous night shifts, and few days off were associated with low patient safety culture. Despite adjusting the working hours, the number of event reports increased with an increase in the number of night shifts. Physicians worked longer and had fewer days off than nurses. However, physicians had fewer composites of patient safety culture score related to working hours, the number of night shifts, and the number of days off than nurses. CONCLUSIONS: This study suggested a possibility of improving the patient safety culture by managing the working environment of healthcare workers. High number of night shifts may lead to high number of event reports. Working hours, the number of night shifts, and the number of days off may differently influence patient safety culture in physicians and nurses.
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Hospitais , Segurança do Paciente , Admissão e Escalonamento de Pessoal/estatística & dados numéricos , Recursos Humanos em Hospital/psicologia , Gestão da Segurança , Estudos Transversais , Pesquisas sobre Atenção à Saúde , Humanos , Japão , Recursos Humanos em Hospital/estatística & dados numéricosRESUMO
This study aims to elucidate the molecular mechanism of an alternative electron flow (AEF) functioning under suppressed (CO2-limited) photosynthesis in the cyanobacterium Synechocystis sp. PCC 6803. Photosynthetic linear electron flow, evaluated as the quantum yield of photosystem II [Y(II)], reaches a maximum shortly after the onset of actinic illumination. Thereafter, Y(II) transiently decreases concomitantly with a decrease in the photosynthetic oxygen evolution rate and then recovers to a rate that is close to the initial maximum. These results show that CO2 limitation suppresses photosynthesis and induces AEF. In contrast to the wild type, Synechocystis sp. PCC 6803 mutants deficient in the genes encoding FLAVODIIRON2 (FLV2) and FLV4 proteins show no recovery of Y(II) after prolonged illumination. However, Synechocystis sp. PCC 6803 mutants deficient in genes encoding proteins functioning in photorespiration show AEF activity similar to the wild type. In contrast to Synechocystis sp. PCC 6803, the cyanobacterium Synechococcus elongatus PCC 7942 has no FLV proteins with high homology to FLV2 and FLV4 in Synechocystis sp. PCC 6803. This lack of FLV2/4 may explain why AEF is not induced under CO2-limited photosynthesis in S. elongatus PCC 7942. As the glutathione S-transferase fusion protein overexpressed in Escherichia coli exhibits NADH-dependent oxygen reduction to water, we suggest that FLV2 and FLV4 mediate oxygen-dependent AEF in Synechocystis sp. PCC 6803 when electron acceptors such as CO2 are not available.
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Dióxido de Carbono/farmacologia , Oxigênio/farmacologia , Proteínas de Plantas/metabolismo , Synechocystis/metabolismo , Respiração Celular/efeitos dos fármacos , Transporte de Elétrons/efeitos dos fármacos , Modelos Biológicos , Mutação/genética , Fotossíntese/efeitos dos fármacos , Complexo de Proteína do Fotossistema II/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Synechocystis/efeitos dos fármacos , Synechocystis/crescimento & desenvolvimento , Água/metabolismoRESUMO
To determine whether alternative electron flow (AEF) can replace the photosynthetic electron flow in cyanobacteria, we used an open O2-electrode system to monitor O2-exchange over a long period. In air-grown Synechocystis sp. PCC 6803 (S. 6803(WT)), the quantum yield of PSII, Y(II), held even after photosynthesis was suppressed by CO2 shortage. The S. 6803 mutant, deficient in flavodiiron (FLV) proteins 1 and 3, showed the same phenotype as S. 6803(WT). In contrast, Y(II) decreased in Synechococcus sp. PCC 7942 (S. 7942). These results suggest that AEF functioned as the Y(II) in S. 6803 and replaced the photosynthetic electron flux. In contrast, the activity of AEF in S. 7942 was lower. The affinity of AEF for O2 in S. 6803 did not correspond to those of FLVs in bacteria or terminal oxidases in respiration. AEF might be driven by photorespiration.
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Transporte de Elétrons/fisiologia , Fotossíntese , Synechococcus/fisiologia , Synechocystis/fisiologia , Respiração Celular , Clorofila/metabolismo , Clorofila/fisiologia , Transporte de Elétrons/genética , Luz , Oxirredução , Oxigênio/metabolismo , Complexo de Proteína do Fotossistema II/genética , Complexo de Proteína do Fotossistema II/metabolismo , Especificidade da Espécie , Synechococcus/genética , Synechocystis/genéticaRESUMO
BACKGROUND: mRNA vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) became common. We investigated the optimal timing for inoculation against SARS-COV-2 in the candidates for cardiac surgery under cardiopulmonary bypass (CPB). METHODS: In 100 patients with preoperative vaccination, who underwent CPB surgery between July 2021 and February 2022, the IgG against the receptor binding domain (RBD-IgG), with a threshold of >100 binding antibody unit (BAU)/mL for adequate immunity, was measured. RESULTS: The vaccines, including 87 BNT162b2 (Pfizer/BioNTech) and 13 mRNA-1273 (Moderna), were inoculated at 98.8 ± 59.4 days before surgery. The median RBD-IgG titers before surgery, 1 day after surgery, and 1 month after surgery were 166.8, 100.0, and 84.0 BAU/mL, respectively. The standby interval (SBI) from the vaccination to the surgery showed a significantly negative correlations with the RBD-IgG titer before the surgery (p < 0.001). A cut-off SBI for RBD-IgG >100 BAU/mL before surgery was <81 days with a sensitivity of 76%, specificity of 62%, and area under ROC value of 0.73 (p = 0.03). The patients with SBI <81 days (n = 48) had significantly higher RBD-IgG (>100 BAU/mL) than those with SBI ⩾81 days (n = 52) at all perioperative periods. CONCLUSIONS: Although 40% of the RBD-IgG titers reduce 1 day after CPB surgery, the patients who received the SARS-COV-2 vaccination within an 81-day window prior to the surgery maintained a desirable RBD-IgG level, even up to 1 month after surgery. It may be important to schedule the surgery no later than 81 days after the vaccination.
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COVID-19 , Ponte Cardiopulmonar , Humanos , Vacinas contra COVID-19 , SARS-CoV-2 , Vacina BNT162 , Vacinação , Imunoglobulina GRESUMO
We report a case of surgically repaired symptomatic mitral valve regurgitation (MR) in a 61-year-old woman with anomalous unilateral single pulmonary vein. A two-staged surgery was scheduled; first a catheter embolization of anomalous vessel to avoid recirculation of the blood into the left atrium during cardiopulmonary bypass, and second a mitral valve repair via right lateral thoracotomy. Learning objective: Scimitar sign is a horn-like shape on plain chest radiograph. One of the possible diagnoses is partial anomalous pulmonary venous return (APVR), which often requires surgical interventions due to comorbidities of congenital heart disease and recurrent pneumonia [1-3]. Another is anomalous unilateral single pulmonary vein (AUSPV), which is generally asymptomatic, and therefore, requires no medical interventions. This case addresses the advantage of multidetector computed tomography (CT) and the safety of two-staged strategy.
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Although a variety of patient safety interventions have been implemented, prioritizing them in a limited resource environment is important. The intervention priorities of patient safety managers may differ from those of patient safety experts. This study aimed to clarify the difference in prioritization of interventions between experts and safety managers to better identify interventions that should be promoted in Japan. We performed a secondary data analysis of two surveys: the Delphi survey for Japanese experts and a nationwide questionnaire survey for safety managers in hospitals. Regarding the 32 interventions constituting 14 organizational-level and 18 clinical-level interventions examined in the previous studies, we assessed three correlations to examine the difference in prioritization between experts and safety managers: correlations between experts and safety managers in the three perspectives (contribution, dissemination, and priority), those between priorities of experts and safety managers at the clinical and organizational level, and those among the three perspectives in experts and safety managers. Contribution (r = 0.768) and dissemination (r = 0.689) of patient safety interventions evaluated by experts and safety managers were positively correlated, but priorities were not. Interventions with priorities that differed between experts and safety managers were identified. In experts, there was no significant correlation between contribution and priority or between dissemination and priority. For safety managers, contributions (r = 0.812) and dissemination (r = 0.691) were positively correlated with priority. Our results suggest that patient safety managers evaluated future priority based on past contributions and current dissemination, whereas experts evaluated future priority based on other factors, such as expected impacts in the future, as mentioned in the previous study. In health policymaking, promotion of patient safety interventions that were given high priority by experts, but low priority by safety managers, should be considered with possible incentives.
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Hospitais , Segurança do Paciente , Humanos , Japão , Formulação de Políticas , Análise de Dados SecundáriosRESUMO
We have developed fluorescent probes for the detection of strand scission in the excision repair of oxidatively damaged bases. They were hairpin-shaped oligonucleotides, each containing an isomer of thymine glycol or 5,6-dihydrothymine as a damaged base in the center, with a fluorophore and a quencher at the 5'- and 3'-ends, respectively. Fluorescence was detected when the phosphodiester linkage at the damage site was cleaved by the enzyme, because the short fragment bearing the fluorophore could not remain in a duplex form hybridized to the rest of the molecule at the incubation temperature. The substrate specificities of Escherichia coli endonuclease III and its human homolog, NTH1, determined by using these probes agreed with those determined previously by gel electrophoresis using (32)P-labeled substrates. Kinetic parameters have also been determined by this method. Since different fluorophores were attached to the oligonucleotides containing each lesion, reactions with two types of substrates were analyzed separately in a single tube, by changing the excitation and detection wavelengths. These probes were degraded during an incubation with a cell extract. Therefore, phosphorothioate linkages were incorporated to protect the probes from nonspecific nucleases, and the base excision repair activity was successfully detected in HeLa cells.
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Dano ao DNA , Reparo do DNA , Desoxirribonuclease (Dímero de Pirimidina)/metabolismo , Proteínas de Escherichia coli/metabolismo , Corantes Fluorescentes/química , Sondas de Oligonucleotídeos/química , Clivagem do DNA , Células HeLa , Humanos , Oligonucleotídeos Fosforotioatos/química , Especificidade por SubstratoRESUMO
OBJECTIVES: Patients with cardiovascular disease are vulnerable to severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection. Although SARS-CoV2 vaccination may be effective, its impact on surgical patients is not well studied. We investigated the effects of cardiovascular surgery, especially under cardiopulmonary bypass (CPB), on the antibody titres after SARS-CoV2 vaccination. METHODS: A prospective observational study was designed for patients undergoing surgery between July and November 2021. The immunoglobulin G against the receptor-binding domain was measured and antibody preserved rate (APR) was calculated from perioperative titres comparison. RESULTS: Enrolled 63 study patients were divided into 39 undergoing surgery with CPB (Group CPB) and 24 without CPB (Group None). Preoperative vaccines were BNT162b2 (Pfizer/BioNTech) (n = 58, 92%) and mRNA-1273 (Moderna) (n = 5, 8%). While immunoglobulin G against the receptor-binding domain titres did not significantly decrease after surgery in Group None, they decreased significantly in Group CPB from 21.80 [11.15, 37.85] to 11.95 [6.80, 18.18] U/ml (P < 0.001) a day after surgery, 11.40 [7.85, 22.65] U/ml (P < 0.001) 14 days after surgery and 7.60 [4.80, 17.60] U/ml (P < 0.001) a month after surgery. The APRs a day after the surgery were significantly lower in Group CPB (0.46 [0.41, 0.60]) than in Group None (0.80 [0.68, 0.87]) (P < 0.001). CONCLUSIONS: The SARS-CoV2 antibody titres significantly decreased with lower APRs immediately after surgery under CPB. Based on our informative results, careful considerations of vaccination schedule might be required for surgery under CPB.
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COVID-19 , Ponte Cardiopulmonar , Vacina BNT162 , Humanos , Imunoglobulina G , RNA Viral , SARS-CoV-2 , VacinaçãoRESUMO
Kommerell diverticulum (KD) is an aneurysm of the orifice of an aberrant subclavian artery (SCA) from the descending aorta or aortic arch. We have performed two-staged surgical strategy for the treatment of KD with right aortic arch. The first step was the bypass grafting between the left common carotid artery and the aberrant left SCA with occlusion of the distal side of KD with the plug. The second step was the descending aorta replacement through the right thoracotomy. Four patients underwent these operations. No hospital deaths or major complications were observed. All four patients were discharged and have been alive for 1-6 years without any health problems. Two of four patients had symptoms of dysphagia preoperatively, and it resolved postoperatively in both patients. No hoarseness occurred after surgery, and 1-6 years of CT observation showed no recanalization of the vascular plug.
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Anormalidades Cardiovasculares , Divertículo , Cardiopatias Congênitas , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Anormalidades Cardiovasculares/complicações , Anormalidades Cardiovasculares/diagnóstico por imagem , Anormalidades Cardiovasculares/cirurgia , Divertículo/diagnóstico por imagem , Divertículo/cirurgia , Humanos , Artéria Subclávia/anormalidades , Artéria Subclávia/diagnóstico por imagem , Artéria Subclávia/cirurgiaRESUMO
We report wound management using a vacuum-assisted closure (VAC) system for the cannula sites of extracorporeal biventricular assist devices (BiVADs) for 295 days in a 23-year old Chinese female patient with fulminant giant cell myocarditis, who finally underwent heart transplantation. When the cannula sites appeared necrotic 3 months after BiVADs placement, she received negative pressure wound therapy prophylactically for four cannula sites, using a VAC system for 3 months, followed by no infections. Such prophylactic VAC therapy, using the skin barrier paste usually used for the ostomy pouching system to create a flatter surface and airtightness, may be useful to avoid cannula site infections, which is still a fatal complication causing sepsis, especially in patients with extracorporeal BiVADs.
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Coração Auxiliar , Tratamento de Ferimentos com Pressão Negativa , Sepse , Adulto , Cânula , Feminino , Coração Auxiliar/efeitos adversos , Humanos , Sepse/etiologia , Sepse/prevenção & controle , Infecção da Ferida Cirúrgica , Adulto JovemRESUMO
Objectives: Despite advances in surgical techniques and management, surgical site infection (SSI) is still important after cardiovascular surgery. We investigated to determine whether or not preoperative nasopharyngeal cultures (NCx) can predict SSI and its microbial spectrum. Methods: A retrospective review was done in 1226 consecutive patients undergoing NCx and cardiac and thoracic aortic surgery via median sternotomy who were cared for with the standard SSI bundle between 2013 and 2018. Microorganisms isolated from the NCx and SSI pathogens were counted to explore the microbial pattern and associated variables in patients with and without postoperative SSI. Perioperative management was not changed by collection of preoperative NCx. Results: There were 1281 and 127 microorganisms, including coagulase-negative Staphylococcus as the most prevalent, isolated from 784 nasal and 111 pharyngeal specimens, respectively. Postoperative SSI occurred in 31 patients (2.47%), including chest, groin, and leg SSI. Significant coincidence of the SSI pathogens with the NCx microorganisms was not observed. However, the patients with SSI showed significantly higher positive rates of preoperative NCx than those without SSI. The sensitivity/specificity of NCx for SSI were 81%/37% for nasal and 45%/92% for pharyngeal, respectively. The negative predictive value of NCx for ruling out SSI was 98.6% for nasal and 98.4% for pharyngeal, respectively. Independent risk factors for postoperative SSI included female sex, diabetes mellitus, positive preoperative NCx, and postoperative use of Portex Mini-Trach (Smiths Medical, Minneapolis, Minn) or tracheostomy on multivariate analysis. Conclusions: Preoperative NCx may be useful to predict SSI after open heart surgery via median sternotomy, as well as screening for methicillin-resistant Staphylococcus aureus.
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BACKGROUND: Bypass for moderately stenosed coronary arteries may cause graft failure (string phenomenon or occlusion). We examined the effects of fractional flow reserve (FFR) on the efficacy of coronary artery bypass grafting (CABG) in preventing graft failure. METHODS: Between January 2013 and December 2017, 48 patients underwent CABG after FFR was measured. Twenty-five grafts in 23 patients were evaluated for graft patency after the procedure. We studied stenosis of native coronary arteries, FFR, graft flow, graft patency, and the presence of pre-procedure and post-procedure myocardial ischemia. RESULTS: Three internal thoracic arteries showed the string sign, and two saphenous vein grafts showed occlusion. All target coronary arteries for these grafts had moderate (50-75%) stenosis. Of the 25 grafts, five failed, and 20 were successful. All grafts with the string sign had been bypassed for target coronary arteries with the gray-zone FFR value (0.75-0.80). No difference in graft flow was observed between the failed and successful grafts. Patients with graft failure had no postoperative myocardial ischemia in target areas despite graft condition. CONCLUSION: Internal thoracic artery graft for coronary arteries with the gray-zone FFR value may exhibit the string phenomenon. We believe that graft failure occurred because the target area had no ischemia before CABG. FFR is useful in pre-operative ischemic evaluation including scintigraphy and will influence the success of revascularization, including the selection of grafts.
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Reserva Fracionada de Fluxo Miocárdico , Ponte de Artéria Coronária , HumanosRESUMO
The (6-4) photoproduct, which is one of the major UV-induced DNA lesions, causes carcinogenesis with high frequency. The (6-4) photolyase is a flavoprotein that can restore this lesion to the original bases, but its repair mechanism has not been elucidated. In this study, we focused on the interaction between the enzyme and the 3' pyrimidone component of the (6-4) photoproduct and prepared a substrate analogue in which the carbonyl group, a hydrogen-bond acceptor, was replaced with an imine, a hydrogen-bond donor, to investigate the involvement of this carbonyl group in the (6-4) photolyase reaction. UV irradiation of oligodeoxyribonucleotides containing a single thymine-5-methylisocytosine site yielded products with absorption bands at wavelengths longer than 300 nm, similar to those obtained from the conversion of the TT site to the (6-4) photoproduct. Nuclease digestion, MALDI-TOF mass spectrometry, and the instability of the products indicated the formation of the 2-iminopyrimidine-type photoproduct. Analyses of the reaction and the binding of the (6-4) photolyase using these oligonucleotides revealed that this imine analogue of the (6-4) photoproduct was not repaired by the (6-4) photolyase, although the enzyme bound to the oligonucleotide with considerable affinity. These results indicate that the carbonyl group of the 3' pyrimidone ring plays an important role in the (6-4) photolyase reaction. On the basis of these results, we discuss the repair mechanism.
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Desoxirribodipirimidina Fotoliase/química , Processos Fotoquímicos , Animais , Cromatografia Líquida de Alta Pressão , Reparo do DNA/genética , Reparo do DNA/efeitos da radiação , Desoxirribodipirimidina Fotoliase/antagonistas & inibidores , Desoxirribodipirimidina Fotoliase/efeitos da radiação , Ensaio de Desvio de Mobilidade Eletroforética , Ligação de Hidrogênio/efeitos da radiação , Hidrólise/efeitos da radiação , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/genética , Oligodesoxirribonucleotídeos/efeitos da radiação , Processos Fotoquímicos/efeitos da radiação , Pirimidinonas/química , Pirimidinonas/efeitos da radiação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Especificidade por Substrato/genética , Especificidade por Substrato/efeitos da radiação , Raios Ultravioleta , Xenopus laevisRESUMO
Purpose: CTG trinucleotide repeat (TNR) expansion is frequently found in transcription factor 4 (TCF4) in Fuchs' endothelial corneal dystrophy (FECD), though the effect of TNR expansion on FECD pathophysiology remains unclear. The purpose of this study was to evaluate the effect of TNR expansion on TCF4 expression in corneal endothelium of patients with FECD. Methods: Peripheral blood DNA and Descemet membrane with corneal endothelium were obtained from 203 German patients with FECD. The CTG TNR repeat length in TCF4 was determined by short tandem repeat (STR) assays and Southern blotting using genomic DNA. Genotyping of rs613872 in TCF4 was performed by PCR. TCF4 mRNA levels in corneal endothelium were evaluated by quantitative PCR using three different probes. Control corneal endothelial samples were obtained from 35 non-FECD subjects. Results: The STR assay and Southern blotting showed that 162 of the 203 patients with FECD (80%) harbored CTG trinucleotide repeat lengths larger than 50. Quantitative PCR using all three probes demonstrated that TCF4 mRNA is significantly upregulated in the corneal endothelium of patients with FECD, regardless of the presence of TNR expansion. However, the length of the TNR tended to show a positive correlation with TCF4 expression level. No correlation was shown between the genotype of TCF4 SNP, rs613872, and the level of TCF4 expression. Conclusions: Our findings showed that TCF4 mRNA is upregulated in the corneal endothelium of patients with FECD. Further studies on the effects of TCF4 upregulation on corneal endothelial cell function will aid in understanding the pathophysiology of FECD.
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Distrofia Endotelial de Fuchs/genética , Regulação da Expressão Gênica/fisiologia , RNA Mensageiro/genética , Fator de Transcrição 4/genética , Expansão das Repetições de Trinucleotídeos , Adulto , Idoso , Idoso de 80 Anos ou mais , Southern Blotting , Feminino , Técnicas de Genotipagem , Humanos , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Adulto JovemRESUMO
The (6-4) photoproduct, which is one of the major UV-induced DNA lesions formed at bipyrimidine sites, causes carcinogenesis at high frequency. The (6-4) photolyases restore the (6-4) photoproducts to their intact bases in a light-dependent manner, but its overall repair mechanism remains obscure. To investigate the light-dependent conversion of the (6-4) photoproduct, we prepared a (6-4) photoproduct analog with modification at 3' pyrimidone ring, in which the carbonyl group was replaced with an imine to apply to the (6-4) photolyase assay. The (6-4) photolyase shows affinity to an oligonucleotide carrying this imine analog of the (6-4) photoproduct, though the imine analog is not repaired by the (6-4) photolyase.
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Desoxirribodipirimidina Fotoliase/química , Nucleotídeos de Timina/química , Dímeros de Pirimidina/químicaRESUMO
We have developed a method for the detection of the endonuclease III reaction by fluorescence. The probes were 13-base-pair hairpin-shaped oligonucleotides containing one of the isomers of thymine glycol or 5,6-dihydrothymine as a damaged base at the center, and had a fluorophore and a quencher at the 5' and 3' ends, respectively. Fluorescence was detected when the probe was cleaved by the enzyme, because the short fragment bearing the fluorophore could not be hybridized to the quencher strand at the incubation temperature. The substrate specificity was shown using Escherichia coli and human enzymes.
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Dano ao DNA , Desoxirribonuclease (Dímero de Pirimidina)/metabolismo , Proteínas de Escherichia coli/metabolismo , Sondas de Oligonucleotídeos/química , Corantes Fluorescentes/química , Humanos , Especificidade por SubstratoRESUMO
Isoaffinetin (5,7,3',4',5'-pentahydroxyflavone-6-C-glucoside) was isolated from Manilkara indica as a potent inhibitor of lens aldose reductase by bioassay-directed fractionation. This C-glucosyl flavone showed specific inhibition against aldose reductases (rat lens, porcine lens and recombinant human) with no inhibition against aldehyde reductase and NADH oxidase. Kinetic analysis showed that isoaffinetin exhibited uncompetitive inhibition against both dl-glyceraldehyde and NADPH. A structure-activity relationship study revealed that the increasing number of hydroxy groups in the B-ring contributes to the increase in aldose reductase inhibition by C-glucosyl flavones.