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Japanese black Wagyu cattle are renowned for producing some of the world's most highly valued and recognized beef with exceptional marbling. Therefore, the primary focus of genetic selection for Wagyu cattle has historically been on meat quality, particularly achieving high marbling levels. However, even when the price of the final product is high, production costs also remain high, especially considering that most of the feed has to be imported. The objective of this study was to evaluate phenotypic relationships between feed efficiency, specifically residual feed intake (RFI), as the most utilized efficiency index in cattle, and various meat quality parameters in Japanese black cattle in order to determine if a common phenotypic selection for these parameters could be feasible. For this, a total of 39 Wagyu cattle were evaluated for feed efficiency over their entire fattening period (900 d), with a focus on RFI as a key indicator. Animals were fed high-starch diets with vitamin A deprivation to achieve the desired marbling. Results revealed positive correlations between feed efficiency and meat quality in Wagyu cattle. Specifically, animals with higher feed efficiency exhibited superior meat quality traits, including firmness, marbling, and overall meat rating. When comparing the 20 most extreme RFI individuals (10 most and 10 least efficient), we observed that efficient RFI animals showed increased marbling levels (+13.2%, Pâ =â 0.05) and ranking quality (+12%, Pâ =â 0.06) of the meat. In conclusion, this research contributes to understanding the interplay between feed efficiency and meat quality in Japanese black Wagyu cattle. Phenotypic correlations observed suggest the possibility of incorporating RFI criteria into genetic selection programs without compromising the prized meat quality traits of Wagyu beef.
The Japanese black cattle, or Wagyu, are known because of its exceptional meat quality and its high degree of marbling. However, to achieve this condition, animals are fed with high amount of concentrate and over long periods of time. In order to decrease both environmental impact and economic profitability of Wagyu producers, feed efficiency may be improved. Therefore, the present work evaluates the phenotypic relationship between meat quality variables of Japanese black cattle and their efficiency of feed utilization. Results showed how individuals with improved efficiency of feed utilization present higher degree of marbling than non-efficient, which may represent the footprint of a new genetic selection program which encompasses both meat quality criteria and feed efficiency values. These results have to be confirmed by genetic studies to verify heritability of these treatments.
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Ração Animal , Dieta , Carne , Fenótipo , Animais , Bovinos/genética , Bovinos/fisiologia , Ração Animal/análise , Dieta/veterinária , Carne/análise , Carne/normas , Masculino , Ingestão de Alimentos , FemininoRESUMO
Bone dysplasias are a group of rare hereditary diseases, with up to 436 disease types. Perinatal diagnosis is clinically important for adequate personalized management and counseling. There are no reports focused on pathogenic variants of bone dysplasias in the general population. In this study, we focused on autosomal recessive bone dysplasias. We identified pathogenic variants using whole-genome reference panel data from 3552 Japanese individuals. For the first time, we were able to estimate the carrier frequencies and the proportions of potential patients. For autosomal recessive bone dysplasias, we detected 198 pathogenic variants of 54 causative genes. We estimated the variant carrier frequencies and the proportions of potential patients with variants associated with four clinically important bone dysplasias: osteogenesis imperfecta (OI), hypophosphatasia (HPP), asphyxiating thoracic dysplasia (ATD), and Ellis-van Creveld syndrome (EvC). The proportions of potential patients with OI, ATD, and EvC based on pathogenic variants classified as "pathogenic" and "likely pathogenic" by InterVar were closer to the reported incidence rates in Japanese subjects. Furthermore, the proportions of potential patients with HPP variants classified as "pathogenic" and "likely pathogenic" in InterVar and "pathogenic" in ClinVar were closer to the reported incidence rates. For bone dysplasia, the findings of this study will provide a better understanding of the variant types and frequencies in the Japanese general population, and should be useful for clinical diagnosis, genetic counseling, and personalized medicine.
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Measurements of aroxyl (ArO · )-radical-scavenging rate constants (ksAOH) of antioxidants (AOHs) (i.e., α-, ß-, γ-, δ-Tocopherol (TocH) and ubiquinol-10 (UQ10H2)) were performed in ethanol/chloroform/H2O (50/50/1, v/v) solution, using stopped-flow spectrophotometry. ksAOH values were measured not only for each AOH, but also for the mixtures of two AOHs (i.e., TocH and UQ10H2). ksTocH values for α-, ß-, γ-, δ-TocH increased 1.21, 1.28, 1.55, and 1.19 times, respectively, under the coexistence of constant concentrations of UQ10H2. Similar measurements were performed for eight vegetable oils 1 - 8, containing different concentrations of α-, ß-, γ-, δ-tocopherol (TocH) and -tocotrienol (Toc-3H). ksOil values of all eight vegetable oils 1 - 8 also increased 1.24 - 1.54 times under the coexistence of constant concentrations of UQ10H2. A new mechanism to explain the notable increase of ksAOH values under the coexistence of two kinds of phenolic AOHs was proposed. UV-vis absorption of α-, ß-, γ-Toc · radicals, produced by reaction of α-, ß-, γ-TocHs (or vegetable oils 1 - 8) with ArO · , disappeared under the coexistence of TocHs (or oils) and UQ10H2, suggesting that the prooxidant reaction resulting from the presence of Toc · radicals is suppressed in the presence of UQ10H2.
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Antioxidantes/química , Sequestradores de Radicais Livres/química , Óleos de Plantas , Ubiquinona/análogos & derivados , Vitamina E/química , Clorofórmio , Etanol , Oxirredução , Óleos de Plantas/química , Soluções , Espectrofotometria/métodos , Ubiquinona/química , ÁguaRESUMO
Recently, singlet-oxygen (1O2) quenching and aroxyl-radical (ArO·) scavenging rates (kQ and kS, respectively) of eight vegetable oils were measured in the ethanol/chloroform/D2O solution. Furthermore, the kQ and kS values and concentrations of four tocopherols and four tocotrienols contained in the vegetable oils were measured. In this study, the concentrations of nine fatty acids (including stearic, oleic, linoleic, and linolenic acids) comprising the above-mentioned eight vegetable oils were determined by gas chromatography. The kQ and kS values for ethyl stearate, ethyl oleate, ethyl linoleate, methyl linolenate, and glyceryl trioleate in the ethanol/chloroform/D2O solution were measured by UV-vis spectrophotometry. Based on the results obtained for the above-mentioned fatty acid esters, the kQ and kS values were estimated for nine fatty acids. Furthermore, comparisons of kQ values observed for the vegetable oils with the sum of the product {∑kQAO-i [AO-i]} of the kQAO-i values obtained for each antioxidant-i (AO-i) and the concentrations ([AO-i]) of AO-i (i.e., four tocopherols (& four tocotrienols) and nine fatty acids) contained in vegetable oils were performed. Based on the results, a detailed comparison of the contributions of the tocopherols (and tocotrienols) and the fatty acids to the 1O2-quenching rate constants (kQ) was performed. This indicated that both the tocopherols (and tocotrienols) and the fatty acids contribute to the 1O2- quenching. A similar comparison was conducted for the ArO· -scavenging rate constants (kS). The results suggested that only the tocopherols (and tocotrienols) contained in the oils contributed to the ArO· -scavenging, with negligible contribution from the fatty acids.
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Ácidos Graxos/química , Sequestradores de Radicais Livres , Óleos de Plantas/química , Oxigênio Singlete/química , Vitamina E/químicaRESUMO
BACKGROUND: Fetal akinesia refers to a broad spectrum of disorders with reduced or absent fetal movements. There is no established approach for prenatal diagnosis of the cause of fetal akinesia. Chromosome 1p36 deletion syndrome is the most common subtelomeric terminal deletion syndrome, recognized postnatally from typical craniofacial features. However, the influence of chromosome 1p36 deletion on fetal movements remains unknown. CASE REPORT: A 32-week-old fetus with akinesia showed multiple abnormalities, including fetal growth restriction, congenital cardiac defects, and ventriculomegaly. G-banding analysis using cultured amniocytes revealed 46,XY,22pstk+. Postnatal whole exome sequencing and subsequent chromosomal microarray identified a 3 Mb deletion of chromosomal region 1p36.33-p36.32. These results of molecular cytogenetic analyses were consistent with the fetal sonographic findings. CONCLUSION: Using the exome-first approach, we identified a case with fetal akinesia associated with chromosome 1p36 deletion. Chromosome 1p36 deletion syndrome may be considered for differential diagnosis in cases of fetal akinesia with multiple abnormalities.
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Monochorionic-triamniotic triplet pregnancy with twin reversed arterial perfusion (TRAP) sequence is one of the rare complications of multiple pregnancy and has been reported by only a few. Here, we report a case of monochorionic-triamniotic triplet pregnancy with TRAP sequence successfully treated with radiofrequency ablation, which did not develop polyhydramnios and heart failure although the estimated weight of the acardiac fetus increased twice as much as that of the direct pump fetus. Interestingly, the anastomosed blood vessels between the direct and indirect pump fetuses comprised a parallel circuit, which provided blood flow to the acardiac fetus. We hypothesized that the burden on the pump fetus in monochorionic pregnancy with TRAP sequence would be different between triplet and twin pregnancies.
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OBJECTIVE: We present a case of fetal severe anemia associated with Jra alloimmunization, which was managed using Doppler measurement of the peak systolic velocity of the fetal middle cerebral artery (MCA-PSV) and intrauterine transfusion (IUT) of Jr(a+) red blood cells (RBCs). We also review the previous case reports on fetal or neonatal anemia associated with Jra alloimmunization. CASE REPORT: A woman with Jra alloimmunization was referred to our department at 29 weeks of gestation. As fetal MCA-PSV exceeded 1.55 multiples of the median, fetal blood sampling was performed and demonstrated severe anemia. During the course, a total of two IUTs were performed using Jr(a+) RBCs. The neonate was delivered by repeated cesarean section at 35 weeks of gestation and showed no apparent signs of hemolysis. CONCLUSION: Based on the literature review, fetal anemia associated with Jra alloimmunization becomes severe during mid-gestation and may not develop during late gestation. The severity of fetal anemia is predicted by MCA-PSV Doppler assessment rather than the maternal anti-Jra titers. Timely IUT of Jr(a+) RBCs can help to prolong the pregnancy to term in emergency situations wherein compatible blood of Jr(a-) RBCs is not available soon.
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A kinetic study of the reaction of singlet oxygen (1O2) with eight vegetable oils 1-8 containing different concentrations of tocopherols (Tocs) and tocotrienols (Toc-3s) was performed. The second-order rate constants (kQ) for the reaction of 1O2 with vegetable oils 1-8 (rice bran, perilla, rape seed, safflower, grape seed, sesame, extra virgin olive, and olive oils) were measured in ethanol/chloroform/D2O (50:50:1, v/v/v) solution at 35°C using UV-vis spectrophotometry. Furthermore, comparisons of kQ values determined for the above oils 1-8 with the sum of the product {∑kQAO-i [AO-i]/105} of the kQAO-i values obtained for each antioxidant (AO-i) and concentration (in mg/100 g) ([AO-i]/105) of AO-i (Tocs and Toc-3s) contained in the oils 1-8 were performed. The observed kQ values were not reproduced by the kQ values calculated using only the concentrations of the four Tocs and Toc-3s. These results suggest that the contribution of fatty acids contained in the oils 1-8 is also necessary to fully explain the kQ values. Recently, the second-order rate constants (kS) for the reaction of aroxyl radical (ArOã») with the same vegetable oils 1-8 were measured in the same solvent at 25â using stopped-flow spectrophotometry (Ref. 23). The kS values obtained could be well explained as the sum of the product {Σ kSAO-i [AO-i]/105} of the kSAO-i and the [AO-i]/105 of AO-i (Tocs and Toc-3s) contained in the vegetable oils.
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Óleos de Plantas/química , Oxigênio Singlete/química , Brassica rapa/química , Carthamus tinctorius/química , Ácidos Graxos/química , Cinética , Olea/química , Oryza/química , Perilla/química , Sesamum/química , Tocoferóis/química , Tocotrienóis/química , Vitis/químicaRESUMO
AIM: Perimortem cesarean section (PCS) is a procedure performed as part of cardiopulmonary resuscitation (CPR). This study aims to clarify maternal and neonatal prognosis and establish PCS's utility and limitations. METHODS: We sent structured questionnaires to obstetrics facilities regarding the cases of PCS performed in Japan between April 2010 and April 2015. Receiver operating characteristic (ROC) curve was used to determine the optimal cut-off values of the time from cardiopulmonary arrest (CPA) to return of spontaneous circulation to predict the onset of disseminated intravascular coagulation (DIC). RESULTS: PCS was performed for 18 patients. Out of 18 patients, 12 were resuscitated. The women who were discharged without major sequelae (n = 6) were compared with the non-discharged women who were dead or in persistent vegetative state (n = 12), and median interval time from arrest to PCS was significantly shorter in the former group (P = 0.002). Median interval time from CPA to PCS in the cases in which the neonates survived without major morbidities was significantly shorter than that in the cases of neonatal death and hypoxic encephalopathy (P = 0.01). DIC was observed in 8/9 (89%) patients whose resuscitation took more than 20 min from the diagnosis of CPA. Percutaneous cardiopulmonary support (PCPS) was introduced in 4/9 patients. However, more cases with uncontrolled bleeding, possibly caused by a sudden increase in blood flow and DIC after resuscitation, were observed in the PCPS group compared to the non-PCPS group. CONCLUSION: PCS can be an effective CPR procedure. However, if PCS is not performed within 20 min from CPA, starting PCPS before PCS is an option.
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Reanimação Cardiopulmonar/métodos , Cesárea/métodos , Parada Cardíaca/terapia , Complicações Cardiovasculares na Gravidez/terapia , Resultado da Gravidez , Adulto , Reanimação Cardiopulmonar/estatística & dados numéricos , Cesárea/estatística & dados numéricos , Feminino , Parada Cardíaca/epidemiologia , Humanos , Japão , Gravidez , Complicações Cardiovasculares na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Estudos RetrospectivosRESUMO
Recently, a new assay method that can quantify the singlet oxygen-absorption capacity (SOAC) of antioxidants (AO) and food extracts in homogeneous organic solvents has been proposed. In the present study, second-order rate constants (kQ ) for the reaction of singlet oxygen (1 O2 ) with vitamin E homologs (α-, ß-, γ-, and δ-tocopherols [Toc] and α-, ß-, γ-, and δ-tocotrienols [Toc-3]) were measured in an aqueous Triton X-100 (5.0 wt%) micellar solution (pH 7.4). Toc-3 showed kQ values larger than those of Toc in a micellar solution, although Toc and Toc-3 showed the same kQ values in a homogeneous solution. Similar measurements were performed for 5 palm oil extracts 1-5 and one soybean extract 6, which contained different concentrations of Toc, Toc-3, and carotenoids. It has been clarified that the 1 O2 -quenching rates (kQ ) (that is, the relative SOAC value) obtained for extracts 3-6 may be explained as the sum of the product ΣkQAO-iAO-i/100 of the rate constant ( kQAO-i ) and the concentration ([AO-i]/100) of AO-i contained. The UV-vis absorption spectra of Toc and Toc-3 were measured in a micellar solution and chloroform. The results obtained demonstrated that the kQ values of AO in homogeneous and heterogeneous solutions vary notably depending on (1) polarity (dielectric constant [ε]) of the reaction field between 1 O2 and AO, (2) the local concentration of AO, and (3) the mobility of AO in solution. The results suggest that the SOAC method is applicable to the measurement of 1 O2 -quenching activity of general food extracts in a heterogeneous micellar solution.
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Glycine max/química , Micelas , Óleo de Palmeira/química , Extratos Vegetais/química , Oxigênio Singlete/análise , Oxigênio Singlete/química , Vitamina E/química , Estrutura Molecular , SoluçõesRESUMO
Singlet-oxygen (1O2) quenching, free-radical scavenging, and excited-state intramolecular proton-transfer (ESIPT) activities of hydroxyflavones, anthocyanidins, and 1-hydroxyanthraquinones were studied by means of laser, stopped-flow, and steady-state spectroscopies. In hydroxyflavones and anthocyanidins, the 1O2 quenching activity positively correlates to the free-radical scavenging activity. The reason for this correlation can be understood by considering that an early step of each reaction involves electron transfer from the unfused phenyl ring (B-ring), which is singly bonded to the bicyclic chromen or chromenylium moiety (A- and C-rings). Substitution of an electron-donating OH group at B-ring enhances the electron transfer leading to activation of the 1O2 quenching and free-radical scavenging. In 3-hydroxyflavones, the OH substitution at B-ring reduces the activity of ESIPT within C-ring, which can be explained in terms of the nodal-plane model. As a result, the 1O2 quenching and free-radical scavenging activities negatively correlate to the ESIPT activity. A catechol structure at B-ring is another factor that enhances the free-radical scavenging in hydroxyflavones. In contrast to these hydroxyflavones, 1-hydroxyanthraquinones having an electron-donating OH substituent adjacent to the O-H---OâC moiety susceptible to ESIPT do not show a simple correlation between their 1O2 quenching and ESIPT activities, because the OH substitution modulates these reactions.
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A kinetic study of the reaction between an aroxyl radical (ArOâ¢) and fatty acid esters (LHs 1-5, ethyl stearate 1, ethyl oleate 2, ethyl linoleate 3, ethyl linolenate 4, and ethyl arachidonate 5) has been undertaken. The second-order rate constants (ks) for the reaction of ArO⢠with LHs 1-5 in toluene at 25.0 °C have been determined spectrophotometrically. The ks values obtained increased in the order of LH 1 < 2 < 3 < 4 < 5, that is, with increasing the number of double bonds included in LHs 1-5. The ks value for LH 5 was 2.93 × 10-3 M-1 s-1. From the result, it has been clarified that the reaction of ArO⢠with LHs 1-5 was explained by an allylic hydrogen abstraction reaction. A similar kinetic study was performed for the reaction of ArO⢠with six carotenoids (Car-Hs 1-6, astaxanthin 1, ß-carotene 2, lycopene 3, capsanthin 4, zeaxanthin 5, and lutein 6). The ks values obtained increased in the order of Car-H 1 < 2 < 3 < 4 < 5 < 6. The ks value for Car-H 6 was 8.4 × 10-4 M-1 s-1. The ks values obtained for Car-Hs 1-6 are in the same order as that of the values for LHs 1-5. The results of detailed analyses of the ks values for the above reaction indicated that the reaction was also explained by an allylic hydrogen abstraction reaction. Furthermore, the structure-activity relationship for the reaction was discussed by taking the result of density functional theory calculation reported by Martinez and Barbosa into account.
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Background. Caesarean scar pregnancy (CSP) is a rare ectopic pregnancy associated with life-threatening complications. To date, no therapeutic protocols have been established. Sono-guided local methotrexate (MTX) injection is a relatively easy and low-invasive treatment. Additional systemic MTX is sometimes needed for CSP cases, especially when ß-subunit human chorionic gonadotropin (ß-hCG) levels are >20,000 mIU/ml at diagnosis. We report on six cases of CSP treated with local MTX injection, five of which received combined local treatment. Methods. Under intravenous anesthesia, six CSPs including a case with ß-hCG levels >20,000 mIU/ml received MTX injection to the gestational sac. Five cases received gestational sac aspiration. Three cases had additional local potassium chloride injection and one case had a saline injection aiming at the fetal heart beat concurrent with MTX injection. MTX was administered weekly if ß-hCG levels stayed beyond the expected values. Outcomes. All cases achieved ß-hCG normalization without additional systemic MTX, with one case having a successful pregnancy after treatment. Conclusion. Sono-guided local MTX injection with concurrent local treatment might be a potentially effective approach for CSP cases. The accumulation of further cases is necessary to confirm this.
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Recently, a new assay method for the quantification of the singlet oxygen absorption capacity (SOAC) of antioxidants (AOs) and food extracts in homogeneous organic solvents was proposed. In this study, second-order rate constants (kQ) for the reaction of singlet oxygen (1O2) with eight different carotenoids (Cars) and α-tocopherol (α-Toc) were measured in an aqueous Triton X-100 (5.0 wt %) micellar solution (pH 7.4, 35 °C), which was used as a simple model of biomembranes. The kQ and relative SOAC values were measured using ultraviolet-visible (UV-vis) spectroscopy. The UV-vis absorption spectra of Cars and α-Toc were measured in both a micellar solution and chloroform, to investigate the effect of solvent on the kQ and SOAC values. Furthermore, decay rates (kd) of 1O2 were measured in 0.0, 1.0, 3.0, and 5.0 wt % micellar solutions (pH 7.4), using time-resolved near-infrared fluorescence spectroscopy, to determine the absolute kQ values of the AOs. The results obtained demonstrate that the kQ values of AOs in homogeneous and heterogeneous solutions vary notably depending on (i) the polarity [dielectric constant (ε)] of the reaction field between AOs and 1O2, (ii) the local concentration of AOs, and (iii) the mobility of AOs in solution. In addition, the kQ and relative SOAC values obtained for the Cars in a heterogeneous micellar solution differ remarkably from those in homogeneous organic solvents. Measurements of kQ and SOAC values in a micellar solution may be useful for evaluating the 1O2 quenching activity of AOs in biological systems.
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Carotenoides/química , Oxigênio Singlete/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , alfa-Tocoferol/química , Antioxidantes/química , Cinética , Micelas , Octoxinol/químicaRESUMO
Site-specific electron relaxations caused by Si:2p core-level photoionizations in F3SiCH2CH2Si(CH3)3 and Cl3SiCH2CH2Si(CH3)3 vapors have been studied by means of the photoelectron Auger electron coincidence spectroscopy. F3SiCH2CH2Si(CH3)3 shows almost 100% site-specificity in fragmentation caused by the Si:2p ionization. However, substitution of Cl for F of F3SiCH2CH2Si(CH3)3 considerably reduces the site-specificity at the Si atom bonded to three halogen atoms, with the site-specificity at the Si site bonded to three methyl groups remaining largely unchanged. The site-specificity reduction in Cl3SiCH2CH2Si(CH3)3 is considered to take place during the transient period between Si:L23VV Auger electron emission and the subsequent fragmentation. The reason for the reduction can be explained in terms of some differences between these two molecules in the L23VV Auger decay at the Si site bonded to the three halogen atoms.
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Detailed kinetic studies have been performed for reactions of aroxyl (ArO(â¢)) and α-tocopheroxyl (α-Toc(â¢)) radicals with five catecholamines (CAs) (dopamine (DA), norepinephrine (NE), epinephrine (EN), and 5- and 6-hydroxydopamine (5- and 6-OHDA)) and two catechins (epicatechin (EC) and epigallocatechin gallate (EGCG)) to clarify the free-radical-scavenging activity of CAs. Second-order rate constants (ks and kr) for reactions of ArO(â¢) and α-Toc(â¢) radicals with the above antioxidants were measured in 2-propanol/water (5:1, v/v) solution at 25.0 °C, using single- and double-mixing stopped-flow spectrophotometries, respectively. Both the rate constants (ks and kr) increased in the order NE < EN < DA < EC < 5-OHDA < EGCG < 6-OHDA. The ks and kr values of 6-OHDA are large and comparable to the corresponding values of ubiquinol-10 and sodium ascorbate, which show high free-radical-scavenging activity. The ultraviolet-visible absorption of α-Toc(â¢) (λmax = 428 nm), which was produced by the reaction of α-tocopherol (α-TocH) with ArO(â¢), disappeared under the coexistence of CAs due to the α-TocH-regeneration reaction. The results suggest that the CAs may contribute to the protection from oxidative damage in nervous systems, by scavenging free radicals (such as lipid peroxyl radical) and regenerating α-TocH from the α-Toc(â¢) radical.
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Catecolaminas/química , Sequestradores de Radicais Livres/química , Radicais Livres/química , alfa-Tocoferol/química , Catequina/análogos & derivados , Catequina/química , Cinética , Oxirredução , Soluções/química , Espectrofotometria , Relação Estrutura-AtividadeRESUMO
Measurements of the reaction of sodium salt of pyrroloquinoline quinone (PQQNa2) with vitamin C (Vit C) were performed in phosphate-buffered solution (pH 7.4) at 25 °C under nitrogen atmosphere, using UV-vis spectrophotometry. The absorption spectrum of PQQNa2 decreased in intensity due to the reaction with Vit C and was changed to that of pyrroloquinoline quinol (PQQH2, a reduced form of PQQ). One molecule of PQQ was reduced by two molecules of Vit C producing a molecule of PQQH2 in the buffer solution. PQQH2, thus produced, was recycled to PQQ due to air oxidation. PQQ and Vit C coexist in many biological systems, such as vegetables, fruits, as well as in human tissues. The results obtained suggest that PQQ is reduced by Vit C and functions as an antioxidant in biological systems, because it has been reported that PQQH2 shows very high free-radical scavenging and singlet-oxygen quenching activities in buffer solutions.
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Antioxidantes/química , Ácido Ascórbico/química , Hidroquinonas/química , Cofator PQQ/química , Ar , Soluções Tampão , Concentração de Íons de Hidrogênio , Oxirredução , Sais , Soluções , EspectrofotometriaRESUMO
Measurements of singlet oxygen ((1)O2) quenching rates (kQ (S)) and the relative singlet oxygen absorption capacity (SOAC) values were performed for seven rice bran extracts 1-7, which contained different concentrations of antioxidants (AOs) (such as α-, ß-, γ-, and δ-tocopherols and -tocotrienols, three carotenoids (lutein, ß-carotene, and zeaxanthin), and γ-oryzanol), in ethanol at 35 °C using UV-vis spectrophotometry. The concentrations of four tocopherols and four tocotrienols, three carotenoids, and γ-oryzanol contained in the extracts were determined using HPLC-MS/MS, UV-HPLC, and UV-vis absorption spectroscopy, respectively. Furthermore, comparisons of kQ (S) (Obsd.) values observed for the above extracts 1-7 with the sum of the product {[Formula: see text] [AO-i]} of the [Formula: see text] values obtained for each AO-i and the concentration ([AO-i]) of AO-i contained in extracts 1-7 were performed. From the results, it has been ascertained that the SOAC method is applicable to general food extracts to evaluate their (1)O2-quenching activity.
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Antioxidantes/química , Etanol/química , Oryza/química , Extratos Vegetais/química , Oxigênio Singlete/química , Espectrofotometria Ultravioleta/métodos , Absorção Fisico-Química , Antioxidantes/análise , Carotenoides/análise , Carotenoides/química , Cinética , Fenilpropionatos/análise , Fenilpropionatos/química , Soluções , Temperatura , Vitamina E/análise , Vitamina E/químicaRESUMO
Excited-state intramolecular proton-transfer (ESIPT) and singlet-oxygen ((1)O2) quenching activities of intramolecularly hydrogen-bonded 1-(acylamino)anthraquinones have been studied by means of static and laser spectroscopies. The ESIPT shows a substituent effect, which can be explained in terms of the nodal-plane model. The ESIPT activity positively and linearly correlates with their (1)O2 quenching activity. The reason for this correlation can be understood by considering ESIPT-induced distortion of their ground-state potential surface and their encounter complex formation with (1)O2. Intramolecularly hydrogen-bonded hydroxyanthraquinones found in aloe also show a similar positive and linear correlation, which can be understood in the same way.
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Antraquinonas/química , Prótons , Oxigênio Singlete/químicaRESUMO
Measurements of the singlet oxygen ((1)O2) quenching rates (kQ (S)) and the relative singlet oxygen absorption capacity (SOAC) values were performed for 11 antioxidants (AOs) (eight vitamin E homologues (α-, ß-, γ-, and δ-tocopherols and -tocotrienols (-Tocs and -Toc-3s)), two vitamin E metabolites (α- and γ-carboxyethyl-6-hydroxychroman), and trolox) in ethanol/chloroform/D2O (50:50:1, v/v/v) and ethanol solutions at 35 °C. Similar measurements were performed for five palm oil extracts 1-5 and one soybean extract 6, which included different concentrations of Tocs, Toc-3s, and carotenoids. Furthermore, the concentrations (wt%) of Tocs, Toc-3s, and carotenoids included in extracts 1-6 were determined. From the results, it has been clarified that the (1)O2-quenching rates (kQ (S)) (that is, the relative SOAC value) obtained for extracts 1-6 may be explained as the sum of the product {Σ kQ(AO-i) (S) [AO-i]/100} of the rate constant (kQ(AO-i) (S)) and the concentration ([AO-i]/100) of AO-i (Tocs, Toc-3s, and carotenoid) included.