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1.
In 2014, bark cankers were observed on Caucasian alder (Alnus subcordata) trees in Iran. The disease was characterized by a dark watery liquid often exuding from longitudinal cankers in the bark of the tree trunks which stained the surface. Symptomatic tissue from A. subcordata was sampled from a number of sites in the Mazandaran province. Isolations were performed on nutrient agar supplemented with sucrose (SNA) and yielded bacterial colonies that were uniform, round and whitish. The bacterial strains isolated from alder trees in Iran were similar to Brenneria alni based on phenotypic and genotypic (nucleotide sequences of the 16S rRNA, and housekeeping genes gyrB, and infB) characteristics. The pathogenicity of the representative strains was determined by inoculating stem pieces of A. subcordata. All tested strains caused longitudinal necrotic lesions 30 days after inoculation and were re-isolated from this tissue. To our knowledge, this is the first report of the occurrence of B. alni in Iran, and on A. subcordata globally.  相似文献   
2.
It has been suggested that exposure to electromagnetic fields may be a risk factor for cardiovascular disease in humans. Low density lipoprotein (LDL) modifications such as peroxidation and aggregation have been implicated in the pathogenesis of atherosclerosis. The present study investigated the effects of weak (0.125–0.5 mT) and moderate (1–4 mT) static magnetic fields (SMFs) on LDL oxidation, aggregation and zeta potential in vitro. Our results demonstrated that magnetic flux densities of 0.25 and 0.5 mT decreased, and magnetic flux densities of 3 and 4 mT increased the zeta potential and LDL oxidation in comparison with the control samples. All doses of SMFs increased the LDL aggregation in a time‐ and dose‐dependent manner. It is concluded that SMFs can alter the susceptibility of LDL to oxidation and this alteration is dependent on the applied magnetic flux density. The SMF, in addition to its role in the production and stabilization of free radicals and promotion of lipid peroxidation, may influence the metabolism of lipoproteins and their interaction with other molecules such as apolipoproteins, enzymes and receptors through the alteration of the LDL zeta potential and its particles tendency to aggregation. Bioelectromagnetics 34:397–404, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
3.
Sleep and Biological Rhythms - Narcoleptics tend to have a low quality of life (QoL). Few studies have compared QoL in narcolepsy against other sleep disorders. The purpose of this study was to...  相似文献   
4.
Gastric cancer is a life-threatening disease; resulting from interaction among genetic, epigenetic, and environmental factors. Aberrant dysregulation and methylation changes in Wnt/β-catenin signaling downstream elements are a prevalent phenomenon encountered in gastric tumorigenesis. Also, viral infections play a role in gastric cancer development. CTNNBIP1 (β-catenin interacting protein 1) gene is an antagonist of Wnt signaling which binds to the β-catenin molecules. The CTNNBIP1 function as tumor suppressor gene or oncogene in different types of cancer is controversial. Moreover, its function and regulatory mechanisms in gastric cancer progression is unknown. In the present study, we examined CTNNBIP1 gene expression, the methylation status of the regulatory region of the gene, and their association with Epstein–Barr virus (EBV), and cytomegalovirus (CMV) and Helicobacter pylori infections in human gastric adenocarcinoma tissues in comparison with their adjacent nontumoral tissues. Our data revealed a significant downregulation of CTNNBIP1 in gastric tumors. Female patients showed lower level of CTNNBIP1 than males (p < 0.05). Also, decreased expression of CTNNBIP1 was markedly associated with well-differentiated tumor grades (p < 0.05). No methylation change was observed between tumoral and nontumoral tissues. Additionally, CTNNBIP1 down regulation was significantly associated with CMV infection (p < 0.05). In the absence of EBV infection, lower expression of CTNNBIP1 was observed. There was no association between H. pylori infection and CTNNBIP1 expression. Our findings revealed the tumor suppressor role for CTNNBIP1 in gastric adenocarcinoma. Interestingly, EBV and CMV infections modulate CTNNBIP1 expression.  相似文献   
5.
Allium is a particularly species rich (more than 800 species) and economically important genus, with numerous taxonomic problems at all levels of classification. In this study, we try to uncover the phylogenetic relationships of the common leek Allium ampeloprasum based on selected samples of this species and its putative relatives in A. sect. Allium from Iran. The silica‐dried leaf samples of 56 accessions representing 23 species of Allium were sequenced; 53 sequences of nrDNA ITS, 35 sequences of plastid rps16 and 52 sequences of trnL–F were generated and additional accessions were extracted from GenBank in order to cover all recognized main lineages in the genus. Maximum Parsimony and Bayesian Inference generated similar trees, but the placement of A. ampeloprasum and its relatives differed slightly between the nuclear and the plastid phylogenies. In the nrITS tree, A. ampeloprasum is retrieved as a highly supported clade with A. iranicum, while in the combined plastid tree A. ampeloprasum formed a highly supported clade with A. vineale. This supports the hypothesis of a possible hybrid origin of A. ampeloprasum. Allium iranicum formed a clade in the plastid tree, but was resolved as paraphyletic in the nrITS tree, probably due to presence of multiple non‐concerted copies of nrITS. Close relationships are suggested between the following species: A. aznavense and A. wendelboi with A. talyschense, A. erubescens and A. rotundum with A. scorodoprasum and A. abbasii with A. phanerantherum.  相似文献   
6.
Various population studies have reported the association of rare S2 allele of apolipoprotein C3 (APOC3) SstI polymorphism with hypertriglyceridemia (HTG) and coronary artery disease (CAD). We were the first to report an association of S2 allele with high triglyceride (TG) levels in healthy volunteers from Northern India. Since HTG is suggested to be a predominant risk factor for CAD among Indians, we have elucidated the relationship of APOC3 SstI polymorphism with the lipid profile and CAD. A total of 158 patients with > or = 70% stenosis in one or more coronary artery (angiographically proven CAD patients), 35 subjects with < 70% stenosis (NCAD) and 151 normal controls (free of heart disease) from Northern plains of India were recruited in the study. DNA samples were analyzed by polymerase chain reaction (PCR) followed by SstI digestion. Lipid profile was estimated by enzymatic kit. We found a strong association of S2 allele with high TG levels, which was more significant in patients. Prevalence of S2 allele in normal controls and CAD patients were comparable, despite the fact that mean TG level was significantly higher in patients. A greater insight into this observation revealed that the prevalence of high TG, if not coupled with other risk factors (like high total cholesterol, low HDL), was comparable in patients and controls. Thus, our study reveals that rare S2 allele may be employed as a susceptibility marker for high TG. However, high TG or S2 allele alone may not contribute to the etiology of CAD.  相似文献   
7.
Kinetic and thermodynamic studies have been made on the effect of the inosine product on the activity of adenosine deaminase in a 50 mM sodium phosphate buffer, pH 7.5, at 27 degrees C using UV spectrophotometry and isothermal titration calorimetry (ITC). A competitive inhibition was observed for inosine as a product of the enzymatic reaction. A graphical-fitting method was used for determination of the binding constant and enthalpy of inhibitor binding by using isothermal titration microcalorimetry data. The dissociation-binding constant is equal to 140 microM by the microcalorimetry method, which agrees well with the value of 143 microM for the inhibition constant that was obtained from the spectroscopy method  相似文献   
8.
A novel cephalosporin derivative of monohydroguaiaretic acid (cephem-M(3)N, 7) was synthesized and found to possess anticancer activity against human leukemia (K562), breast carcinoma (MCF7), human lung cancer (A549), human colon cancer (Colo205) and pancreatic cancer cells (Capan2 and MiaPaCa2). A tumor targeting fusion protein (dsFv3-beta-lactamase) was also used in conjunction with cephem-based M(3)N 7 and its potency toward K562, MCF7, A549, Colo205, Capan2, and MiaPaCa2 was found to approach that of the free M(3)N (4). In the presence of dsFv3-beta-lactamase, tumor cells were found to be much more susceptible to conjugate 7 than normal human embryonic lung (HEL) cells and normal fibroblasts (Hef522). These notions provide a new approach to the use of nordihydroguaiaretic acid (NDGA) and its derivatives for antitumor therapy.  相似文献   
9.
Hyperglycemia and the accumulation of advanced glycation endproducts (AGEs) in tissues and serum have important roles in diabetic complications. Therefore, the identification of anti-glycation compounds is attracting considerable interest. In this study, the interaction of human serum albumin (HSA) with fructose, in the absence and presence of alginate, was studied by circular dichroism, absorbance and fluorescence techniques. The characterization study of AGEs was performed using autofluorescence, fibrillar formation, the increase in absorbance and the quantification of free lysine side chains. The results indicate that alginate inhibits the fructation of HSA as observed by a reduction in the formation of fluorescent AGEs and fibrils. Furthermore, alginate reduces the amount of modified lysine side chains, signified by the lack of increase in absorbance, and increases the helicity of this protein.  相似文献   
10.
Reviews in Fish Biology and Fisheries - Humans have relied on coastal resources for centuries. However, current growth in population and increased accessibility of coastal resources through...  相似文献   
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