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101.
It has recently been reported that bilirubin forms a complex with Cu(II). In this paper we show that the formation of the complex results in the reduction of Cu(II) to Cu(I) and the redox cycling of the metal gives rise to the formation of reactive oxygen species, particularly hydroxyl radical. The bilirubin-Cu(II) complex causes strand breakage in calf thymus DNA and supercoiled plasmid DNA. Cu(I) was shown to be an essential intermediate in the DNA cleavage reaction by using the Cu(I) specific sequestering reagent neocuproine. Bilirubin-Cu(II) produced hydroxyl radical and the involvement of active oxygen species was established by the inhibition of DNA breakage by various oxygen radical quenchers. 相似文献
102.
Mohammad Reza Emad Hadi Momeninejad Babak Pourabbas Tahvildari 《Somatosensory & motor research》2017,34(4):213-218
Despite differences in the anatomical and physiological characteristics of the medial gastrocnemius (MG), lateral gastrocnemius (LG), and soleus (Sol) muscles, it is common practice to investigate them as single triceps surae H-reflex recordings. The aim of this study was to compare the latencies of H-reflex recordings from the Sol, MG, and LG in patients with explicit magnetic resonance imaging (MRI) evidence of unilateral S1 radiculopathy and also compare their diagnostic yield in varied clinical characteristics (i.e., symptom duration and severity of involvement). We found a significant difference between H-reflex latencies of Sol and the two others (p?0.05 for both comparisons). Although Sol had more sensitivity in patients with positive straight leg raising (SLR) of 30°–50° and also the sub-acute phase of the disease, and MG and LG had more sensitivity in the acute phase of the disease and patients with positive SLR of 50°–70°, there were no statistically significant differences between diagnostic ability of the three heads of the triceps surae in various clinical settings and they can be used interchangeably in patients with suspected S1 radiculopathies. 相似文献
103.
Mahdi Ghanbari Hadi Shahraki Wolfgang Kneifel Konrad J. Domig 《Symbiosis (Philadelphia, Pa.)》2017,72(3):183-193
This study addresses the biodiversity profile of bacterial community in the intestinal lumen and mucosa of snow trout fish by applying 16S rRNA gene 454-pyrosequencing. A total of 209,106 sequences with average length 689 (±53) were filtered, denoised, trimmed, and then sorted into OTUs based on 97 % sequence similarity using the USEARCH software pipeline. Bacteria representing 10 phyla were found in the samples investigated. Fimicutes ribotypes were present in intestinal-mucosa and lumen in all fish and often dominated the libraries (average 43 and 38 %, respectively). Proteobacteria were also prevalent, but at a lower relative abundance, at 22 and 29 % in mucosa and lumen, respectively. The autochthonous microbiota was dominated by sequences belonging to the Bacilli (mean sequence abundance 24 %), in particular the Lactobacillaceae, with Lactobacillus and Pediococcous being the most abundant genera. Fewer Bacilli (mean sequence abundance 22 %) and Actinobacteria (2 %) were present in the lumen, and allochthonous communities consisted of a more even split among the bacterial classes, with increases in sequences assigned to members of the γ-Proteobacteria (16 %) and Fusobacteriia (8 %). The principal bacterial genera recorded in the lumen belonged to the lactic acid bacteria group, Cetobacterium, Clostridium and Synechococcus. Results obtained suggest that the lumen and mucosal layer of the snow trout intestine may host different microbial communities. Moreover, both regions harbour a diverse microbiome with a greater microbial diversity in the intestinal mucus compared with the luminal communities of the fish. Many of these microbes might be of high physiological relevance for the fish and may play key roles in the functioning of its gut. 相似文献
104.
According to our analysis of literature sources on the family Hydraenidae (Coleoptera: Staphylinoidea) of Iran, it is represented by 67 species and three genera: Hydraena Kugelann, 1794 (21 species), Limnebius Leach, 1815 (six species) and Ochthebius Leach, 1815 (40 species). Twenty-two species are supposed to be endemic to Iran. Here, for the first time, we summarize species distribution data in Iranian provinces and present them in a checklist of Iranian Hydraenidae. We also present two additional species lists: one with incorrect records (one species and one subspecies) and the other with unidentified species. 相似文献
105.
Well-defined polymer scaffolds convertible to (multi)functional polymer structures via selective and efficient modifications potentially provide an easy, versatile, and useful approach for a wide variety of applications. Considering this, a homopolymer scaffold, poly(pyridyldisulfide ethylmethacrylate) (poly(PDSM)), having pendant groups selectively reactive with thiols, was synthesized by reversible addition fragmentation chain transfer (RAFT) polymerization. Soluble polymers with controlled molecular weights and narrow PDIs were generated efficiently. The versatility of the scaffold to generate random co- and ter-polymers combining multiple functionalities with controlled-composition was shown by separate and simultaneous conjugation of different mercapto-compounds, including a tripeptide in one-step. Conversion of water-insoluble scaffold to peptide-containing water-soluble copolymers was observed to yield nanometer-size particles with narrow polydispersity. The overall results suggest that the well-defined PDSM homopolymer scaffold generated via RAFT polymerization can be a versatile building block for generation of new structures having potential for drug delivery applications via a straightforward synthetic approach. 相似文献
106.
Massah AR Adibi H Khodarahmi R Abiri R Majnooni MB Shahidi S Asadi B Mehrabi M Zolfigol MA 《Bioorganic & medicinal chemistry》2008,16(10):5465-5472
Silica sulfuric acid catalyzes efficiently the reaction of sulfonamides with both carboxylic acid anhydrides and chlorides under solvent-free and heterogeneous conditions. All the reactions were done at room temperature and the N-acylsulfonamides were obtained with high yields and purity via an easy work-up procedure. This method is attractive and is in a close agreement with green chemistry. These compounds were also investigated for antibacterial activity, including Gram-positive cocci and Gram-negative bacilli, and carbonic anhydrase II inhibitory activity. 相似文献
107.
Hadi Mozafari Zohreh Rahimi Azadeh Heidarpour Mahsa Fallahi Adraiana Muniz 《Molecular biology reports》2009,36(8):2361-2364
It has been suggested that the allele frequency of thrombophilic mutations is affected by glucose-6-phosphate dehydrogenase
(G6PD) deficiency. The prevalence of thrombophilic mutations were studied in sixty G6PD deficient individuals including 57
males and three females with the mean age of 15 ± 3.08 and 110 age and sex matched healthy individuals consisted of 95 males and 15 females with
the mean age of 16.19 ± 2.17 from the Kermanshah Province of Iran. Using a combination of PCR-RFLP technique, single strand
conformation polymorphism (SSCP) analysis and DNA sequencing polymorphic G6PD mutations were identified. The factor V Leiden,
prothrombin G20210A and methylenetetrahydrofolate reductase (MTHFR) C677T were detected by PCR-RFLP method using MnlI, HindIII
and HinfI restriction enzymes, respectively. Three mutations, G6PD Mediterranean, G6PD Chatham and G6PD Cosenza were identified
in 60 G6PD deficient individuals with highest prevalence of G6PD Mediterranean (91.6%). In G6PD deficient individuals the
prevalence of factor V Leiden tended to be higher (5%) compared to healthy individuals (2.7%). The prevalence of prothrombin
G20210A mutation in G6PD deficient individuals was 1.7%. However, in normal subjects the prevalence of this mutation was 2.7%.
The frequency of T allele in G6PD deficient individuals were insignificantly higher (29.16%) than those in healthy individuals
(26.8%). Our finding indicates that the prevalence of factor V Leiden, prothrombin G20210A and MTHFR C677T in G6PD deficient
individuals is not statistically different compared to normal subjects and G6PD deficiency is not associated with these thrombophilic
mutations in Western Iran. 相似文献
108.
Seyed Jafar Mousavy Gholam Hossein Riazi Mahmood Kamarei Hadi Aliakbarian Naghmeh Sattarahmady Ahmad Sharifizadeh Shahrokh Safarian Faizan Ahmad Ali Akbar Moosavi–Movahedi 《International journal of biological macromolecules》2009,44(3):278-285
Widespread use of mobile phones has increased the human exposure to electromagnetic fields (EMFs). It is required to investigate the effect of EMFs on the biological systems. In this paper the effect of mobile phone RF (910 MHz and 940 MHz) on structure and function of HbA was investigated. Oxygen affinity was measured by sodium dithionite with UV–vis spectrophotometer. Structural changes were studied by circular dichroism and fluorescence spectroscopy. The results indicated that mobile phone EMFs altered oxygen affinity and tertiary structure of HbA. Furthermore, the decrease of oxygen affinity of HbA corresponded to the EMFs intensity and time of exposure. 相似文献
109.
Khalit Mohamad Yusuke Hirasawa Marc Litaudon Khalijah Awang A. Hamid A. Hadi Koichi Takeya Wiwied Ekasari Aty Widyawaruyanti Noor Cholies Zaini Hiroshi Morita 《Bioorganic & medicinal chemistry》2009,17(2):727-730
Three new limonoids, ceramicines B–D (1–3), have been isolated from the bark of Chisocheton ceramicus. Structures and stereochemistry of 1–3 were fully elucidated and characterized by 2D NMR analysis. Ceramicines exhibited a moderate antiplasmodial activity. 相似文献
110.