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The distribution of C-heterochromatin and nucleolar organizer regions (NORs) was studied in three species of voles of the Microtus arvalis group in Iran: M. mystacinus, M. kermanensis, and M. transcaspicus. The C-banding pattern and NORs distribution were similar in M. mystacinus and M. kermanensis suggesting taxonomic proximity of these two species. At the same time, the karyotypes of M. mystacinus from Iran were different in C-banding pattern from the complements of conspecific 54-chromosome voles from Europe and other regions of Asia. The most distinct difference was in size of the distal C-positive block of heterochromatin on the X chromosome. In this respect M. mystacinus from Iran and M. kermanensis resembled M. transcaspicus. Small size of the distal C-positive heterochromatic block may be ancestral whereas larger size is derived. The X chromosome of M. transcaspicus can be derived from that of M. mystacinus and M. kermanensis by a large inversion or centromeric shift.  相似文献   
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Iron chlorosis is very common on alkaline soils such as calcareous ones, since iron availability is limited by high pH. Under these conditions of iron deficiency, graminaceous plant species induce special mechanisms for iron acquisition, involving enhanced release of iron chelators called phytosiderophores. On the other hand, it is known that most of salt soils have alkaline pH. So, plants growing on this kind of soils are often subjected simultaneously to salinity and iron deficiency. This work aimed at (i) studying the physiological responses of barley (Hordeum vulgare L.) to iron deficiency, and (ii) evaluating the effect of salt on the iron nutrition and the phytosiderophore release. For this purpose, seedlings of Hordeum vulgare L. were cultivated under controlled conditions, either in a complete nutrient solution with or without NaCl, or in an iron free nutrient solution containing or not NaCl. The plant morphological aspect, chlorophyll content of young leaves, iron status, biomass production, and phytosiderophore release by roots were assessed. Plants subjected to Fe deficiency exhibited a severe chlorosis, accompanied by a significant biomass reduction. These plants developed more lateral roots than the control with a highly stimulated phytosiderophore release. However, the latter was greatly diminished when iron deficiency was associated to salinity. A depressive effect of salt on iron acquisition in plants subjected only to salt stress which was also observed and further confirmed by the important decrease of efficiency in iron acquisition. These results suggest that salinity may reduce capacity of plants to acquire iron from alkaline soils by inhibiting phytosiderophore release.  相似文献   
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Introduction

Bone marrow oedema (BME) and avascular osteonecrosis (AVN) are disorders of unclear origin. Although there are numerous operative and non-operative treatments for AVN, pain management in patients with AVN remains challenging. Prostaglandins play an important role in inflammatory responses and cell differentiation. It is thought that prostaglandin I2 ([PGI2] or synonoma prostacyclin) and its analogues promote bone regeneration on a cellular or systemic level. The purpose of this study was to assess the curative and symptomatic efficacy of the prostacyclin analogue iloprost in BME and AVN patients.

Method

We are reporting on 50 patients (117 bones) affected by BME/AVN who were treated with iloprost. Pain levels before, during and 3 and 6 months after iloprost application were evaluated by a visual analogue scale (VAS). The short form(SF)-36 health survey served to judge general health status before and after treatment. Harris Hip Score (HHS) and Knee Society Score (KSS) were performed as functional scores and MRI and X-rays before and 3 and 6 months after iloprost application served as objective parameters for morphological changes of the affected bones.

Results

We found a significant improvement in pain, functional and radiological outcome in BME and early AVN stages after iloprost application, whereas patients with advanced AVN stages did not benefit from iloprost infusions. Mean pain level decreased from 5.26 (day 0) to 1.63 (6 months) and both HHS and KSS increased during follow-up. Moreover, the SF-36 increased from 353.2 (day 0) to 560.5 points (6 months). We found a significant decrease in BME on MRI scans after iloprost application.

Conclusions

In addition to other drugs, iloprost may be an alternative substance which should be considered in the treatment of BME/AVN-associated pain.  相似文献   
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Three new polymeric mercury(II) thiocyanate coordination polymers, {[Hg2(L4)(SCN)4]n (1), [Hg2(μ-L5)(μ-SCN)4]n[Hg2(μ-L5)(μ-SCN)4]2n (2) and [Hg(L6)(SCN)2]n (3); L4 = 2,5-bis(2-pyridyl)-3,4-diaza-2,4-hexadiene, L5 = 2,5-bis(3-pyridyl)-3,4-diaza-2,4-hexadiene and L6 = 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene) were prepared from reactions of mercury(II) thiocyanate with three organic nitrogen donor-based ligands under thermal gradient conditions using the branched tube method and fully characterized by infrared spectroscopy, elemental analysis, thermo gravimetric analysis, and single crystal X-ray diffraction. The compounds are structurally diverse and show very interesting structural motifs: the compound 1 is one-dimensional heterochiral double-chains. In compound 2, the bridging ligand L5 adopts a transoid conformation and the network contains two interpenetrating coordination polymers, a 2D net and a 1D double-chain. The crystal structure of 3 consists of one-dimensional zigzag chains. Solid-state luminescent spectra of the compounds 1 and 3 indicate intense fluorescent emissions at ca. 393 nm and 363 nm, respectively.  相似文献   
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Tuberculosis control relies on the identification and preventive treatment of people who are latently infected with Mycobacterium tuberculosis (Mtb). PE/PPE proteins have been reported to elicit CD4 and/or CD8 responses either in the form of whole recombinant proteins or as individual peptides. Very few of the PE and PPE proteins have been previously tested for responses in patients with TB and healthy donors. This is the first study to evaluate the Interferon Gamma Release Assay (IGRA) after stimulation with PE35 and PPE68. The antigenspecific levels of IFN-γ following stimulation with QuantiFERON-TB gold in-tube (QFT-G-IT) antigens, and PE35 and PPE68 recombinant proteins were evaluated in 79 children and 102 adults, respectively. Using QFT-G-IT kit, latent tuberculosis infection (LTBI) was detected in 26 children (33%) and 41 adults (40%); IGRA following stimulation with PE35 and PPE68 recombinant proteins, was positive, respectively, in 36 (46%) and 32 (40.5%) children, respectively. In addition, 53 adults (52%) had positive results following stimulation with these two proteins. The sensitivity and specificity ofIGRAfollowing stimulation with recombinant PE35 in children were76%and 80%, and following stimulation with recombinant PPE68 in this group, it was 73% and 75%, respectively. Meanwhile, there is no gold standard test for LTBI. Our designed tests using PE35 and PPE68 PE/PPE proteins, two PE/PPE proteins not present in BCG vaccins, which elicit CD4 and/or CD8 responses, might be helpful for rapid diagnosis of TB and improve the detection of LTBI. However, further validation studies to determine the advantage of IGRAs using these proteins, alone or combined, are highly recommended.  相似文献   
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