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101.
Spleen tyrosine kinase (SYK) is a non receptor type tyrosine kinase and a known candidate tumor suppressor gene in breast carcinoma. Loss of Syk is associated with breast cancer invasion and increased cell mortality. The main goal of our study was to detect germ-line polymorphisms in SYK gene in breast cancer affected females of Pakistani origin, in order to understand the genetic basis of complex human breast cancer. Seven novel SYK gene SNPs were identified in breast cancer patients. Among these, three were identified in intronic region, one at the 5'splice donor site (5'SD) and three in 5'untranslated region (5'UTR) of SYK gene. Mutations at the 5'SD and at 5'UTR can be crucial and could be responsible for generation of mutated Syk protein. In silico analysis of the 5'UTR variations revealed that one of the mutations was responsible for generation of a more stable structure of 5'UTR. Such a change in pre-mRNA could potentially down regulate SYK expression. These findings add to the growing literature implicating dysfunctional SYK gene as a contributor to human breast cancer, and suggest that therapies targeting its molecular pathways could provide effective means of treating/preventing breast cancer. 相似文献
102.
103.
Phloridzin reduces blood glucose levels and improves lipids metabolism in streptozotocin-induced diabetic rats 总被引:2,自引:0,他引:2
Najafian M Jahromi MZ Nowroznejhad MJ Khajeaian P Kargar MM Sadeghi M Arasteh A 《Molecular biology reports》2012,39(5):5299-5306
Phloridzin is the specific and competitive inhibition of sodium/glucose cotransporters in the intestine (SGLT1) and kidney
(SGLT2). This property which could be useful in the management of postprandial hyperglycemia in diabetes and related disorders.
Phloridzin is one of the dihydrochalcones typically contained in apples and in apple-derived products. The effect of phloridzin
orally doses 5, 10, 20 and 40 mg/kg body weight on diabetes was tested in a streptozotocin-induced rat model of diabetes type
1. From beneficial effect of this compound is significant reduction of blood glucose levels and improve dyslipidemia in diabetic
rats. As a well-known consequence of becoming diabetic, urine volume and water intake were significantly increased. Administration
of phloridzin reduced urine volume and water intake in a dose-dependent manner. Phloretin decreases of food consumption, as
well as a marked lowering in the weight. In conclusion, this compound could be proposed as an antihyperglycemic and antihyperlipidemic
agent in diabetes and potential therapeutic in obesity. 相似文献
104.
Maziah Mahmood Siamak Shirani Bidabadi Cyrus Ghobadi Dennis J. Gray 《Plant Growth Regulation》2012,67(2):161-169
Although irregular monoterpenes are important and common in the Asteraceae family, little is known about their biosynthesis
at the genetic level via the MEP pathway. Chrysanthemyl diphosphate (CPP) is an intermediate in the biosynthesis of pyrethrins
which are irregular monoterpenes with excellent insecticidal activity in Tanacetum cinerariaefolium (T. cinerariaefolium). In this study, a chrysanthemyl diphosphate synthase (CDS) gene named CDS_CCI2 (GenBank accession no. HQ235057) was isolated from T. cinerariaefolium. It was homologous to T. cinerariaefolium CPP gene family, and proved to be located in the plastid by the in situ subcellular localization. CDS_CCI2 was found to be expressed in roots, stems, leaves, buds and flowers. Moreover, the expression of CDS_CCI2 can be up-regulated by abscisic acid (ABA), methyl jasmonate and ethrel treatment. Phenotypic and molecular analysis showed
that overexpression of CDS_CCI2 in micro-tom tomato resulted in dwarf phenotypes characterized with infertile flowers and seedless fruits. Furthermore, overexpression
of CDS_CCI2 altered the production of endogenous secondary metabolites. Our data indicate that CPP affects the synthesis of gibberellic
acid (GA) and ABA. 相似文献
105.
Husain SZ Orabi AI Muili KA Luo Y Sarwar S Mahmood SM Wang D Choo-Wing R Singh VP Parness J Ananthanaravanan M Bhandari V Perides G 《American journal of physiology. Gastrointestinal and liver physiology》2012,302(12):G1423-G1433
Biliary pancreatitis is the most common etiology for acute pancreatitis, yet its pathophysiological mechanism remains unclear. Ca(2+) signals generated within the pancreatic acinar cell initiate the early phase of pancreatitis, and bile acids can elicit anomalous acinar cell intracellular Ca(2+) release. We previously demonstrated that Ca(2+) released via the intracellular Ca(2+) channel, the ryanodine receptor (RyR), contributes to the aberrant Ca(2+) signal. In this study, we examined whether RyR inhibition protects against pathological Ca(2+) signals, acinar cell injury, and pancreatitis from bile acid exposure. The bile acid tauro-lithocholic acid-3-sulfate (TLCS) induced intracellular Ca(2+) oscillations at 50 μM and a peak-plateau signal at 500 μM, and only the latter induced acinar cell injury, as determined by lactate dehydrogenase (LDH) leakage. Pretreatment with the RyR inhibitors dantrolene or ryanodine converted the peak-plateau signal to a mostly oscillatory pattern (P < 0.05). They also reduced acinar cell LDH leakage, basolateral blebbing, and propidium iodide uptake (P < 0.05). In vivo, a single dose of dantrolene (5 mg/kg), given either 1 h before or 2 h after intraductal TLCS infusion, reduced the severity of pancreatitis down to the level of the control (P < 0.05). These results suggest that the severity of biliary pancreatitis may be ameliorated by the clinical use of RyR inhibitors. 相似文献
106.
Mohammad ZuberKhalid Mahmood Zia Ijaz Ahmad BhattiTahir Jamil Fazal-ur-RehmanAli Rizwan 《Carbohydrate polymers》2012,87(4):2439-2446
A series of aqueous solutions of poly(vinyl alcohol) of various commercial products were prepared and applied onto the surfaces of cotton and blends of cotton/polyester fabrics. Fourier transform infrared spectrophotometer was used to confirm the molecular structure of the polyvinyl alcohol used. Performance tests such as colorfastness to rubbing (dry and wet) and colorfastness to washing were determined. The controlling variables affecting the performance properties of the finished substrate such as post-treatment with poly(vinyl alcohol) of various commercial trades, concentration and dilutions were studied. Crocking, washing and hue change of the treated dyed and printed fabrics is accompanied by the formation of semi-inter-penetrated network structure due to the presence of the hydroxyl (-OH) groups which make feasible to a number of grafting and physical cross linking reactions of polymer backbone. 相似文献
107.
Prey availability affects many aspects of predators' life history and is considered a primary factor influencing individuals' decisions regarding spatial ecology and behavior, but few experimental data are currently available. Snakes may represent ideal model organisms relative to other animal groups for addressing such resource dependency, due to a presumably more direct link between food resources and many aspects of behavior and natural history. We experimentally investigated the relationship between food intake and spatial behavior in a population of the snake Bothrops asper in a Costa Rican lowland rainforest. Six adult snakes were allowed to forage naturally while six were offered supplemental food in the field, with both groups monitored using radiotelemetry. Mean home range size did not differ between groups presumably due to small sample size, but supplementally fed snakes demonstrated altered patterns of macro- and microhabitat selection, shorter and less frequent movements, and increased mass acquisition. Fed snakes also devoted less time to foraging efforts, instead more frequently remaining inactive and utilizing shelter. Because snakes were always fed in situ and not at designated feeding stations, observed shifts in habitat selection are not explained by animals simply moving to areas of higher food availability. Rather, B. asper may have moved to swamps in order to feed on amphibians when necessary, but remained in preferred forest habitat when food was otherwise abundant. The strong behavioral and spatiotemporal responses of snakes in this population may have been influenced by an overall scarcity of mammalian prey during the study period. 相似文献
108.
109.
Zeissig S Murata K Sweet L Publicover J Hu Z Kaser A Bosse E Iqbal J Hussain MM Balschun K Röcken C Arlt A Günther R Hampe J Schreiber S Baron JL Moody DB Liang TJ Blumberg RS 《Nature medicine》2012,18(7):1060-1068
In most adult humans, hepatitis B is a self-limiting disease leading to life-long protective immunity, which is the consequence of a robust adaptive immune response occurring weeks after hepatitis B virus (HBV) infection. Notably, HBV-specific T cells can be detected shortly after infection, but the mechanisms underlying this early immune priming and its consequences for subsequent control of viral replication are poorly understood. Using primary human and mouse hepatocytes and mouse models of transgenic and adenoviral HBV expression, we show that HBV-expressing hepatocytes produce endoplasmic reticulum (ER)-associated endogenous antigenic lipids including lysophospholipids that are generated by HBV-induced secretory phospholipases and that lead to activation of natural killer T (NKT) cells. The absence of NKT cells or CD1d or a defect in ER-associated transfer of lipids onto CD1d results in diminished HBV-specific T and B cell responses and delayed viral control in mice. NKT cells may therefore contribute to control of HBV infection through sensing of HBV-induced modified self-lipids. 相似文献
110.
AH Mahvi AA Roodbari R Nabizadeh Nodehi S Nasseri MH Dehghani M Alimohammadi 《PloS one》2012,7(7):e27571
Landfills leachates are known to contain recalcitrant and/or non-biodegradable organic substances and biological processes are not efficient in these cases. A promising alternative to complete oxidation of biorecalcitrant leachate is the use of ultrasonic process as pre-treatment to convert initially biorecalcitrant compounds to more readily biodegradable intermediates. The objectives of this study are to investigate the effect of ultrasonic process on biodegradability improvement. After the optimization by factorial design, the ultrasonic were applied in the treatment of raw leachates using a batch wise mode. For this, different scenarios were tested with regard to power intensities of 70 and 110 W, frequencies of 30, 45 and 60 KHz, reaction times of 30, 60, 90 and 120 minutes and pH of 3, 7 and 10. For determining the effects of catalysts on sonication efficiencies, 5 mg/l of TiO(2) and ZnO have been also used. Results showed that when applied as relatively brief pre-treatment systems, the sonocatalysis processes induce several modifications of the matrix, which results in significant enhancement of its biodegradability. For this reason, the integrated chemical-biological systems proposed here represent a suitable solution for the treatment of landfill leachate samples. 相似文献