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31.
Methionine (Met) in proteins can be oxidized to two diastereoisomers of methionine sulfoxide, Met‐S‐O and Met‐R‐O, which are reduced back to Met by two types of methionine sulfoxide reductases (MSRs), A and B, respectively. MSRs are generally supplied with reducing power by thioredoxins. Plants are characterized by a large number of thioredoxin isoforms, but those providing electrons to MSRs in vivo are not known. Three MSR isoforms, MSRA4, MSRB1 and MSRB2, are present in Arabidopsis thaliana chloroplasts. Under conditions of high light and long photoperiod, plants knockdown for each plastidial MSR type or for both display reduced growth. In contrast, overexpression of plastidial MSRBs is not associated with beneficial effects in terms of growth under high light. To identify the physiological reductants for plastidial MSRs, we analyzed a series of mutants deficient for thioredoxins f, m, x or y. We show that mutant lines lacking both thioredoxins y1 and y2 or only thioredoxin y2 specifically display a significantly reduced leaf MSR capacity (–25%) and growth characteristics under high light, related to those of plants lacking plastidial MSRs. We propose that thioredoxin y2 plays a physiological function in protein repair mechanisms as an electron donor to plastidial MSRs in photosynthetic organs.  相似文献   
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The colonization patterns of oceanic islands are often interpreted through transmarine dispersal. However, in islands with intense human activities and unclear geological history, this inference may be inappropriate. Cyprus is such an island, whose geotectonic evolution has not been clarified yet to the desired level for biogeographical reconstructions, leaving the questions of ‘how the Cypriote biota arrived’ and ‘does the dispersal have the formative role in patterns of its diversification’ unanswered. Here, we address these issues through a reconstruction of the evolutionary history of six herptiles (Ablepharus budaki, Ophisops elegans, Acanthodactylus schreiberi, Telescopus fallax, Pelophylax cf. bedriagae, and Hyla savignyi) by means of mitochondrial DNA (cytochrome b and 16S rRNA), applying a Bayesian phylogenetic, biogeographical, and chronophylogenetic analyses. The phylogeographical analyses show that the colonization history of those species in Cyprus started in the late Miocene and extended into the Pliocene and Pleistocene, with geodispersal, transmarine dispersal, and human‐mediated dispersal having their share in shaping the diversification of Cypriote herptiles. The revealed patterns could be divided into three biogeographical categories: old colonizers that arrived in Cyprus during the late Miocene or early Pliocene either by a land bridge (geodispersal) which connected Cyprus with the mainland or by transmarine dispersal, younger colonizers that reached the island through transmarine dispersal from the Middle East, and new settlers that arrived through human‐induced (voluntary or not) introductions. This work advances our knowledge of the biogeography of Cyprus and highlights the need to consider both geo‐ and transmarine dispersal when dealing with islands whose associations do not have a straightforward interpretation. © 2013 The Linnean Society of London  相似文献   
34.
The Persian Lizard, Iranolacerta brandtii, was until recently considered to be restricted to north-western Iran (Azerbaijan and Esfahan provinces). However, two recent studies have revealed the existence of populations in Eastern Anatolia, extending the range of this species for about 230?km westwards. The fragmented distribution of this species has been considered to be a consequence of the climatic oscillations during the Pleistocene and Holocene, which created events of alternating contact and isolation of populations in distinct glacial refugia. According to our obtained genealogy derived from three mitochondrial fragments (12S rRNA, 16S rRNA and cytb), the Turkish specimens cluster together but form an independent clade, sister to the individuals from Tabriz in Iran. The separation of these two clades is concurrent with the cladogenesis between the Esfahan and Ardabil clades, estimated to have taken place during the late Holocene.  相似文献   
35.
Psychophysical thresholds for the detection of a 300-Hz burst of vibration applied to the thenar eminence were measured for stimuli applied to the skin through 1.5?cm2 and through 0.05?cm2 contactors. Thresholds were approximately 13?dB lower when the area of the contactor was 1.5?cm2 than when it was 0.05?cm2. The difference between the thresholds measured with the large and small contactors was significantly reduced when only the lowest thresholds obtained in the testing sessions were considered. This result supports the hypothesis that one component of spatial summation in the P channel is probability summation. In addition, threshold measurements within a session were less variable when measured with the 1.5?cm2 contactor. We conclude that spatial summation in the P channel is a joint function of two processes that occur as the areal extent of the stimulus increases: probability summation in which the probability of exceeding the psychophysical detection threshold increases as the number of receptors of varying sensitivities increases, and neural integration in which neural activity originating from separate receptors is combined within the central nervous system rendering the channel more sensitive to the stimulus.  相似文献   
36.
The question of Kurdish language rights has been a central issue in the Turkish–Kurdish conflict. The current study examined endorsement of Kurdish language rights in relation to intergroup factors (i.e. group identifications, cross-group friendships, perceived discrimination, and perceived out-group beliefs about state unity) among self-identified Turkish and Kurdish participants. The results indicate that Turks were much less in favour of these rights than the Kurds. In addition, for the Turks, higher national and ethnic identification were associated with lower support for Kurdish language rights, while cross-group friendship, perceived discrimination of Kurds and the belief that Kurds endorse national unity were associated with more support for rights. For the Kurdish participants, stronger national identification seems to undermine the mobilizing meaning that Kurdish group identification has for language rights support. Furthermore, friendship with Turks can undermine the support for rights because it strengthens national identification and reduces ethnic identification.  相似文献   
37.
A series of hydroxy and phenolic compounds have been assayed for the inhibition of two physiologically relevant carbonic anhydrase (CA, EC 4.2.1.1) isozymes, the cytosolic human isozymes I and II. The investigated molecules showed inhibition constants in the range of 1.07–4003 and 0.09–31.5?μM at the hCA I and hCA II enzymes, respectively. In order to investigate the binding mechanisms of these inhibitors, in silico studies were also applied. Molecular docking scores of the studied compounds are compared using three different scoring algorithms, namely Glide/SP, Glide/XP and Glide/IFD. In addition, different ADME (absorption, distribution, metabolism and excretion) analysis was performed. All the examined compounds were found within the acceptable range of pharmacokinetic profiles.  相似文献   
38.
Symptoms resembling those associated with phytoplasma presence were observed in pomegranate (Punica granatum L.) trees in June 2012 in the Aegean Region of Turkey (Ayd?n province). The trees exhibiting yellowing, reduced vigour, deformations and reddening of the leaves and die‐back symptoms were analysed to verify phytoplasma presence. Total nucleic acids were extracted from fresh leaf midribs and phloem tissue from young branches of ten symptomatic and five asymptomatic plants. Nested polymerase chain reaction assays using universal phytoplasma‐specific 16S rRNA and tuf gene primers were performed. Amplicons were digested with Tru1I, Tsp509I and HhaI restriction enzymes, according to the primer pair employed. The phytoplasma profiles were identical to each other and to aster yellows (16SrI‐B) strain when digestion was carried out on 16Sr(I)F1/R1 amplicons. However, one of the samples showed mixed profiles indicating that 16SrI‐B and 16SrXII‐A phytoplasmas were present when M1/M2 amplicons were digested, the reamplification of this sample with tuf cocktail primers allowed to verify the presence of a 16SrXII‐A profile. One pomegranate aster yellows strain AY‐PG from 16S rRNA gene and the 16SrXII‐A amplicon from tuf gene designed strain STOL‐PG were directly sequenced and deposited in GenBank under the Accession Numbers KJ818293 and KP161063, respectively. To our knowledge, this is the first report of 16SrI‐B and 16SrXII‐A phytoplasmas in pomegranate trees.  相似文献   
39.

Zika virus has recently evolved from an obscure mosquito-borne pathogen to an international public health concern. People with Zika virus disease can have indications including mild fever, skin rash, conjunctivitis, muscle pain, malaise or headache. Effective vaccines are needed for controlling and preventing the disease. In the current study, we aim to design the substructure for vaccine against Zika virus by forming antigenic peptide epitope of the disease. Zika peptide loaded poly (lactic-co-glycolic acid) (PLGA) nanoparticles have been fabricated in the present work as a potential artificial vaccine. UV and FT-IR Spectrophotometers and ZetaSizer were used for studying the nanoparticles, and Scanning Electron Microscope was used for morphological examination. The nanoparticles (NPs) yield, encapsulation efficiency, the peptide loading capacity were determined and in vitro release of the peptide was studied. Cytotoxic effects of the various concentrations of Zika peptide, blank PLGA nanoparticles and Zika peptide loaded PLGA nanoparticles on ECV304 human epithelial cells were determined via MTT assay. The present paper could be considered as one of the important steps in the use of nanoparticles for constructing the new generation of vaccination systems.

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40.
Laurocerasus officinalis Roem. (syn: Prunus laurocerasus L.) is a member of Rosaceae family. We investigated the antimicrobial and antioxidant activity of L. officinalis Roem in wound healing both in vivo and in vitro using an excisional wound model model in mice. We used four groups of eight mice as follows: untreated (control), empty gel, extract + gel (L. officinalis + gel), and Madecassol® groups. All treatments were applied topically once daily. The scar area, percentage wound closure and epithelization time were measured. L. officinalis promoted wound healing and increased granulation tissue, epidermal regeneration and angiogenesis. L. officinalis extract, which is known for its antioxidant and antimicrobial activities, may be useful for promoting wound healing.  相似文献   
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