Cognate status modulates the comprehension of isolated reduced forms

Цель. Установить влияние неспецифического адреноблокатора карведилола на редокс-статус низкомолекулярных аминотиолов (цистеин, гомоцистеин, глутатион) в плазме крови при моделировании глобальной ишемии головного мозга у крыс. Методика. Нами была использована модель глобальной ишемии (пережатие общих сонных артерий с геморрагией длительностью 15 мин). Препарат вводили за 1 ч до операции. Уровни аминотиолов измеряли через 40 мин после начала реперфузии. Анализ уровня аминотиолов проводили методом жидкостной хроматографии. Результаты. Установлено, что у крыс, не подвергавшихся ишемии, карведилол в дозе 10 мг/кг вызывает рост редокс-статуса цистеина и глутатиона (в 3 и 3,5 раза соответственно по сравнению с контролем, p = 0,04 и p = 0,008) за счет увеличения их восстановленных форм. При ишемии данного эффекта не наблюдалось. Редокс-статус у крыс с ишемией на фоне карведилола (Цис = 0,85 ± 0,14%, Глн = 1,8 ± 0,7%, Гцис = 1,1 ± 0,8%) оставался таким же низким, как и у крыс с ишемией без введения карведилола (р > 0,8). Заключение. Полученный результат демонстрирует, что в условиях ишемии головного мозга карведилол не оказывает эффекта на гомеостаз аминотиолов плазмы крови, несмотря на выраженный антиоксидантный эффект в нормальных условиях. Aim. Effect of a nonspecific adrenergic antagonist carvedilol on the redox status of plasma low-molecular-weight aminothiols (cysteine, homocysteine, glutathione) was studied in rats with global cerebral ischemia (occlusion of common carotid arteries with hemorrhage). Methods. A model of global ischemia (occlusion of common carotid arteries with 15-min hemorrhage) was used. The drugs were administered one hour before the operation. Aminothiol levels were measured by HPLC with UV detection at 40 minutes after the onset of reperfusion. Results. Carvedilol 10 mg/kg increased the redox status of cysteine and glutathione in rats not exposed to ischemia (3 and 3.5 times, respectively, compared with the control, p = 0.04 and p = 0.008, respectively) but not of homocysteine, by increasing their reduced forms. However, this effect was not observed in ischemia. In rats with ischemia treated with carvedilol, the redox status (Cys = 0.85 ± 0.14%, GSH = 1.8 ± 0.7%, Hcys = 1.1 ± 0.8%) remained low similar to that in rats with ischemia not treated with carvedilol (p >0.8, 0.8, and 0.9, respectively). Conclusion. Carvedilol did not affect the homeostasis of blood plasma thiols in cerebral ischemia despite the pronounced antioxidant effect under the normal conditions.

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Type 2 diabetes mellitus in patients with acute ischemiс stroke is associated with a decrease in plasma glutathione levels

Russian neurological Journal ◽

10.30629/2658-7947-2020-25-5-29-35 ◽

2020 ◽

Vol 25 (5) ◽

pp. 29-35

Author(s):

M. Yu. Maksimova ◽

A. V. Ivanov ◽

K. A. Nikiforova ◽

F. R. Ochtova ◽

E. T. Suanova ◽

...

Keyword(s):

Diabetes Mellitus ◽

Type 2 Diabetes ◽

Type 2 Diabetes Mellitus ◽

Redox Status ◽

Reduced Form ◽

Glutathione Level ◽

Total Glutathione ◽

Diabetes Mellitus Group ◽

Reduced Forms

Ischemic stroke (IS) and type 2 diabetes mellitus are factors that aﬀect the homeostasis of low-molecularweight aminothiols (cysteine, homocysteine, glutathione etc.). It has already been shown that IS in the acute period led to a decrease a level of reduced forms of aminothiols, but it is not clear whether type 2 diabetes mellitus has a noticeable eﬀect there. Objective: to reveal the features of homeostasis of aminothiols in patients with type 2 diabetes mellitus in acute IS. Material and methods. The study involved 76 patients with primary middle cerebral artery IS in the first 10–24 hours after development of neurological symptoms. Group 1 included 15 patients with IS and type 2 diabetes mellitus, group 2 — 61 patients with IS and stress hyperglycemia. Their total plasma levels of cysteine, homocysteine, and glutathione, their reduced forms, and redox status were determined at admission (in the first 24 hours after IS). Results. There was a decrease in the level of total glutathione level (1.27 vs. 1.65 μM, p = 0.021), as well as its reduced form (0.03 vs. 0.04 μM, p = 0.007) in patients with IS and type 2 diabetes mellitus. Patients with type 2 diabetes mellitus who had a low redox status of homocysteine (0.65–1.2%) and glutathione (0.7–2.0%) were also characterized by a decrease in total glutathione level (p = 0.02; p = 0.03). Conclusion. Thus, type 2 diabetes mellitus is associated with a decrease in the level of total glutathione in acute IS. Probably, type 2 diabetes mellitus is characterized by a particular relationship between the metabolism of homocysteine, glutathione and glucose. Therefore, the search for homocysteine-dependent approaches to correct glutathione metabolism in type 2 diabetes mellitus may be of interest as an adjuvant therapy for IS.

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The influence of nicotinamide and preparations containing it on the level of oxidated and reduced forms of nicotinamide coenzymes in the retina of rats with streptosotocine diabetes

Oftalmologicheskii Zhurnal ◽

10.31288/oftalmolzh201315761 ◽

2013 ◽

Vol 41 (1) ◽

pp. 57-61

Author(s):

V. Sakovich ◽

◽

Ahmad Abed Al Raheem Abdallah Aqrabawi ◽

Keyword(s):

Nicotinamide Coenzymes ◽

Reduced Forms

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Dynamics of Oxidation of Reduced Forms of CO2 under Electrochemical and Open-Сircuit Conditions on Polycrystalline Pt in H2CO3

Metals ◽

10.3390/met11020274 ◽

2021 ◽

Vol 11 (2) ◽

pp. 274

Author(s):

Alexander V. Smolin ◽

Мikhail N. Mikhailov ◽

Aleksey F. Gadzaov ◽

Leonid M. Kustov

Keyword(s):

Quantum Chemical ◽

Preliminary Analysis ◽

Oxidation Reaction ◽

Density Functional ◽

Oxidation Process ◽

Open Circuit ◽

Organic Substances ◽

Oxidation Of Co ◽

Reduced Forms

The problem of identifying correlations between catalytic and electrocatalytic processes is one of the fundamental problems of catalysis among “simple” organic substances, and the oxidation of CO and rCO2 is of great interest, since CO and CO2 are considered in pairs both during catalytic and electrocatalytic transformations. In the case of electrocatalysis, this analysis is important in the study of fuel cells. In this paper, we studied the correlation between the oxidation of reduced forms of CO2 (rCO2) under potentiodynamic-galvanoctatic electrochemical and open-circuit conditions of measurements on polycrystalline (pc)Pt in H2CO3. Periodic oscillations are revealed at the oxidation of Had and rCO2 on (pc)Pt. Quantum chemical calculations were carried out on the Pt13 cluster in order to identify the mechanisms of the rCO2 oxidation reaction. The correspondence in the energy parameters of the oxidation process of rCO2 under open-circuit conditions and electrochemical conditions is shown. The preliminary analysis of the system using density functional (DFT) calculations is carried out and the most stable systems that are based on Pt13 are found, namely rOH-Pt13-(CO)n, rOH-Pt13-(COH) and rOH-Pt13-(rCOOH). OH• species was chosen as the most likely candidate for the role of the oxidant for rCO2. Preliminary calculations for the expected reactions were carried out, and the optimal PES is revealed.

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Peptide-Bound Methionine Sulfoxide (MetO) Levels and MsrB2 Abundance Are Differentially Regulated during the Desiccation Phase in Contrasted Acer Seeds

Antioxidants ◽

10.3390/antiox9050391 ◽

2020 ◽

Vol 9 (5) ◽

pp. 391 ◽

Cited By ~ 3

Author(s):

Natalia Wojciechowska ◽

Shirin Alipour ◽

Ewelina Stolarska ◽

Karolina Bilska ◽

Pascal Rey ◽

...

Keyword(s):

Desiccation Tolerance ◽

Methionine Sulfoxide ◽

Redox Status ◽

Embryonic Axes ◽

Seed Desiccation ◽

Methionine Sulfoxide Reductases ◽

Norway Maple ◽

Orthodox Seeds ◽

Oxidation Of Methionine ◽

Reduced Forms

Norway maple and sycamore produce desiccation-tolerant (orthodox) and desiccation-sensitive (recalcitrant) seeds, respectively. Drying affects reduction and oxidation (redox) status in seeds. Oxidation of methionine to methionine sulfoxide (MetO) and reduction via methionine sulfoxide reductases (Msrs) have never been investigated in relation to seed desiccation tolerance. MetO levels and the abundance of Msrs were investigated in relation to levels of reactive oxygen species (ROS) such as hydrogen peroxide, superoxide anion radical and hydroxyl radical (•OH), and the levels of ascorbate and glutathione redox couples in gradually dried seeds. Peptide-bound MetO levels were positively correlated with ROS concentrations in the orthodox seeds. In particular, •OH affected MetO levels as well as the abundance of MsrB2 solely in the embryonic axes of Norway maple seeds. In this species, MsrB2 was present in oxidized and reduced forms, and the latter was favored by reduced glutathione and ascorbic acid. In contrast, sycamore seeds accumulated higher ROS levels. Additionally, MsrB2 was oxidized in sycamore throughout dehydration. In this context, the three elements •OH level, MetO content and MsrB2 abundance, linked together uniquely to Norway maple seeds, might be considered important players of the redox network associated with desiccation tolerance.

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Reduced forms in the nominal morphology of the Lindisfarne Gospel Gloss. A case of accusative/dative syncretism?

Folia Linguistica ◽

10.1515/flih-2020-0002 ◽

2020 ◽

Vol 54 (s41) ◽

pp. 37-65

Author(s):

Julia Fernández-Cuesta ◽

Nieves Rodríguez-Ledesma

Keyword(s):

Statistical Analysis ◽

Old English ◽

Frequency Condition ◽

Facsimile Edition ◽

Noun Class ◽

Characteristic Features ◽

Nominal Morphology ◽

Reduced Forms ◽

Syntactic Context

Abstract One of the most characteristic features of the grammar of the Lindisfarne Gospel gloss is the absence of the etymological -e inflection in the dative singular in the paradigm of the strong masculine and neuter declension (a-stems). Ross (1960: 38) already noted that endingless forms of the nominative/accusative cases were quite frequent in contexts where a dative singular in -e would be expected, to the extent that he labeled the forms in -e ‘rudimentary dative.’ The aim of this article is to assess to what extent the dative singular is still found as a separate case in the paradigms of the masculine and neuter a-stems and root nouns. To this end a quantitative/statistical analysis of nouns belonging to these classes has been carried out in contexts where the Latin lemma is either accusative or dative. We have tried to determine whether variables such as syntactic context, noun class, and frequency condition the presence or absence of the -e inflection, and whether the distribution of the inflected and uninflected forms is different in the various demarcations that have been identified in the gloss. The data have been retrieved using the Dictionary of Old English Corpus. All tokens have been checked against the facsimile edition and the digitised manuscript in order to detect possible errors.

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An HPLC-automated Derivatization for Glutathione and Related Thiols Analysis in Brassica rapa L.

Agronomy ◽

10.3390/agronomy11061157 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1157

Author(s):

Francesco Nacca ◽

Concetta Cozzolino ◽

Petronia Carillo ◽

Pasqualina Woodrow ◽

Amodio Fuggi ◽

...

Keyword(s):

Brassica Rapa ◽

High Performance ◽

Internal Standard ◽

Plant Tissues ◽

Cellular Functions ◽

Sulphur Compounds ◽

Stress Protection ◽

Automated Method ◽

Reduced Forms

The high content of glucosinolates and glutathione makes the Brassicaceae an important healthy food. Thiols and especially glutathione and γ-Glu-Cys-Gly tripeptide are involved in many fundamental cellular functions such as oxidative stress protection. Although several methods for sulphur compounds analysis in biological samples are actually used, the determination of glutathione and other sulphur derivatives in plant tissues is rather problematic due to their extreme susceptibility to oxidation, which can lead to their overestimation. The aim of this work was the improvement and validation of an automated method for determination of reduced and oxidised glutathione, cysteine and γ-glutamylcysteine in plant tissues. The method consists of a fully automated pre-column derivatization of thiols based on monobromobimane reagent, a high-performance liquid chromatography derivatives separation, and a fluorimetric detection and quantification. The method was successfully applied for determination of the oxidized and reduced forms of Cys, γ-GC and GSH content in leaves, petioles, inflorescences and roots of Brassica rapa L. subsp. Sylvestris. At harvest, in freshly cut plants, the average contents of GSH/2GSSG were 840/45, 345/70 and 150/70 nmol g−1 FW for the florets, leaf blades and stems, respectively; those of Cys/2Cys were 80/12, 29/12 and 24/6 nmol g-1 FW; while those of γ-GC/γ-GCCG-γ were 8.0/4.0, and 6.0/3.0, 3.0/2.0 nmol g−1 FW, respectively. Such amounts were lower in low-sulphur-grown plants at harvest. The very low coefficient of variation between repeated tests (maximum 1.6%), the high recovery of internal standard (>96%) and the linear correlation coefficient of the calibration (R2 > 0.99) support the efficiency of this method that allowed analysing about 50 samples/die in a totally automated manner with no operator intervention. Our results show that the reported method integrations can significantly improve thiols detection via HPLC.

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Captions and reduced forms instruction: The impact on EFL students’ listening comprehension

ReCALL ◽

10.1017/s0958344013000219 ◽

2013 ◽

Vol 26 (1) ◽

pp. 44-61 ◽

Cited By ~ 24

Author(s):

Jie Chi Yang ◽

Peichin Chang

Keyword(s):

Language Learners ◽

Listening Comprehension ◽

Short Term Memory ◽

Limited Capacity ◽

Short Term ◽

Term Memory ◽

Efl Learners ◽

Efl Students ◽

The Impact ◽

Reduced Forms

AbstractFor many EFL learners, listening poses a grave challenge. The difficulty in segmenting a stream of speech and limited capacity in short-term memory are common weaknesses for language learners. Specifically, reduced forms, which frequently appear in authentic informal conversations, compound the challenges in listening comprehension. Numerous interventions have been implemented to assist EFL language learners, and of these, the application of captions has been found highly effective in promoting learning. Few studies have examined how different modes of captions may enhance listening comprehension. This study proposes three modes of captions: full, keyword-only, and annotated keyword captions and investigates their contribution to the learning of reduced forms and overall listening comprehension. Forty-four EFL university students participated in the study and were randomly assigned to one of the three groups. The results revealed that all three groups exhibited improvement on the pre-test while the annotated keyword caption group exhibited the best performance with the highest mean score. Comparing performances between groups, the annotated keyword caption group also emulated both the full caption and the keyword-only caption groups, particularly in the ability to recognize reduced forms. The study sheds light on the potential of annotated keyword captions in enhancing reduced forms learning and overall listening comprehension.

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