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281.
Acetylcholine stimulates insulin secretion in the presence of physiological concentrations of glucose. Stimulation of insulin secretion by acetylcholine is accompanied by an increase in glucose usage by isolated rat islets. Acetylcholine increased glucose usage by 38%, 28%, and 12% at 3.5 mM, 5.5 mM, and 10 mM glucose, respectively, compared to glucose usage by isolated islets incubated with glucose alone. Data showing increased glucose usage in islets treated with acetylcholine converge with data from an earlier report (J. Biol. Chem. 254 3921-3929 [1979]) showing a crossover point for glycolytic metabolites at phosphofructokinase to indicate that activation of glycolysis by acetylcholine results from increased phosphofructokinase activity and coordinate activation of hexokinase in intact islets. 相似文献
282.
Soha Namazi Arghavan Daneshian Mohammad Mohammadianpanah Peyman Jafari Shirin Ardeshir-Rouhani-Fard Shiva Nasirabadi 《Gene》2013
Introduction
Several proteins of renin–angiotensin system (RAS) have been implicated in the process of growth promotion or inhibition of breast tissue and cancer cells. This study aimed to investigate the association between angiotensin I converting enzyme (ACE) insertion/deletion (I/D) and angiotensin receptor-1 (AGTR1) A1166C polymorphisms and survival of 110 women with breast cancer.Materials and methods
The I/D and A1166C polymorphisms were evaluated by using Polymerase Chain Reaction (PCR) and Restriction Fragment Length Polymorphism (RFLP) in 110 breast cancer patients who had been treated between 2007 and 2009. Genomic DNA was extracted from a Formalin-Fixed Paraffin-Embedded (FFPE) tissue of breast cancer sample blocks. All the potential clinical and pathological prognostic variables were analyzed to establish the impact of I/D and A1166C polymorphisms on disease-free and overall survival rates. Disease-free and overall survival rates were the primary endpoints of the study.Results
The ACE (I/D) polymorphism was associated with 3-year disease-free survival. Disease-free survival in DD carriers was significantly increased compared to ID plus II carriers (HR = 4.75; 95% CI, 1.39–16.24; p = 0.013). No significant association was found between AGTR1 (A1166C) and 3-year disease-free survival (p = 0.233). Also, the ACE (I/D) and AGTR1 (A1166C) polymorphisms were not associated with breast cancer overall survival.Conclusion
The ACE (I/D) polymorphism was associated with 3-year disease-free survival of the women with breast cancer. Besides, disease-free survival in DD carriers was significantly increased compared to ID plus II carriers. 相似文献283.
Sako Mirzaie Kambiz Najafi Mohammad Saeed Hakhamaneshi Ahmad Reza Shahverdi Fardin Fathi 《Journal of biomolecular structure & dynamics》2013,31(5):1016-1026
Resistance to antibiotics in bacteria, is one of the major problems of mankind. Each year, a large number of patients due to infection, lose their lives. One of the main mechanisms of antibiotic resistance is beta-lactamase secretion. This enzyme hydrolyzes the amide bond of a lactam ring in beta-lactam antibiotics. Bacillus licheniformis is a mesophilic gram-positive bacterium, which has a high potential to produce beta-lactamase class A. In this study, the inhibitory effects of some malate analogous were studied by in vitro and in vivo studies. In addition, the effects of inhibitor binding on beta-lactamase were studied using MD simulations. Our results showed that diethyl malate and 1-methyl malate can decrease the MIC value of benzyl penicillin by sixteen and eight-fold, respectively. Data derived from in vitro studies revealed that decrease in MIC values is correlated with beta-lactamase inhibition. Molecular docking studies predicted the binding mode of inhibitors with the beta-lactamase active site. The structural analysis from MD simulations exhibits that binding of citrate and diethyl malate causes earlier equilibrium of beta-lactamase. After binding, the fluctuation of Ser 70 is also decreased. Based on our data, diethyl malate can be used to design the potent inhibitor against beta-lactamase class A. 相似文献
284.
Adeleh Divsalar Ali Akbar Saboury Hassan Mansoori-Torshizi Mahboube Islami Moghaddam Faizan Ahmad Golam Hossein Hakimelahi 《Journal of biomolecular structure & dynamics》2013,31(5):587-597
Abstract An new water-soluble Pd(II) complex, 2,2′-bipyridin n-butyl dithiocarbamato Pd(II) nitrate has been synthesized. The Pd(II) complex has been characterized by elemental analysis and conductivity measurements as well as spectroscopic methods such as infrared, 1H NMR, and ultraviolet-visible. The interaction between this new design Pd(II)-complex, an anti-tumor component, with carrier proteins of β-lactoglobulin-A and -B (BLG-A and -B) were studied at different temperatures of 27, 37, 42, and 47 °C by fluorescence spectroscopy and far-UV circular dichroism (CD) spectrophotometric techniques. A strong fluorescence quenching interaction of Pd(II) complex with BLG-A and -B was observed at different temperatures. The binding parameters were evaluated by fluorescence quenching method. The thermodynamic parameters, including ΔH°, ΔS°, and ΔG° were calculated by fluorescence quenching method indicated that the electrostatic and hydrophobic forces might play a major role in the interactions of Pd(II) complex with BLG-A and -B, respectively. The distances between donors (Trps of the BLG-A and -B) and acceptor (Pd(II) complex) were obtained according to the fluorescence resonance energy transfer (FRET). Far-UV CD studies showed that the Pd(II) complex did not represent any significant changes in the secondary structures of BLG- A and -B. The difference in the interaction properties observed for BLG-A and -B with Pd(II) complex is related to the difference in the amino acid sequences between these two variants. 相似文献
285.
Background
Dietary supplementation with methyl donors can influence the programming of epigenetic patterns resulting in persistent alterations in disease susceptibility and behavior. However, the dietary effects of methyl donors on pain have not been explored. In this study, we evaluated the effects of dietary methyl donor content on pain responses in mice.Methods
Male and female C57BL/6J mice were treated with high or low methyl donor diets either in the perinatal period or after weaning. Mechanical and thermal nociceptive sensitivity were measured before and after incision.Results
Mice fed high or low methyl donor diets displayed equal weight gain over the course of the experiments. When exposed to these dietary manipulations in the perinatal period, only male offspring of dams fed a high methyl donor diet displayed increased mechanical allodynia. Hindpaw incision in these animals caused enhanced nociceptive sensitization, but dietary history did not affect the duration of sensitization. For mice exposed to high or low methyl donor diets after weaning, no significant differences were observed in mechanical or thermal nociceptive sensitivity either at baseline or in response to hindpaw incision.Conclusions
Perinatal dietary factors such as methyl donor content may impact pain experiences in later life. These effects, however, may be specific to sex and pain modality. 相似文献286.
Masumeh Moghaddam 《ZooKeys》2013,(334):1-92
A list of scale insects (Hemiptera: Sternorrhyncha: Coccoidea) of Iran is present based mainly on the literature records since 1902. In total, 13 families and 275 species have been recorded and these are listed along with their locality data and host plants. The families are as follows: Asterolecaniidae, Cerococcidae, Coccidae, Diaspididae, Eriococcidae, Kermesidae, Margarodidae, Monophlebidae, Ortheziidae, Phoenicococcidae, Pseudococcidae, Putoidae and Rhizoecidae. The following ten species are recorded for the first time from Iran: Diaspidiotus lenticularis (Lindinger), Diaspidiotus wuenni (Lindinger), Fiorinia proboscidaria Green, Koroneaspis lonicerae Borchsenius, Eriococcus cingulatus Kiritchenko, Eriococcus pamiricus (Bazarov), Eriococcus reynei Schmutterer, Eriococcus sanguinairensis Goux and Eriococcus saxidesertus (Borchsenius) and Porphyrophora victoriae Jashenko. 相似文献
287.
E. Uhlmann D. W. Will G. Breipohl A. Peyman D. Langner J. Knolle 《Nucleosides, nucleotides & nucleic acids》2013,32(5-6):603-608
Abstract The synthesis of polyamide nucleic acids (PNAs) and derivatives thereof by different synthetic routes is described. The first strategy makes use of 9-Fluorenylmethoxycarbonyl (Fmoc)/monomethoxytrityl (Mmt) protected building blocks, whereas the second approach involves the use of Mmt/acyl protected monomers, which allows the preparation of PNADNA chimera. Additionally, a block coupling strategy is presented for the synthesis of novel phosphonic ester nucleic acids (PHONAs). 相似文献
288.
Hydrodistilled essential oils of 21 accessions of Ocimum basilicum L. belonging to two different varieties (var. purpurascens and var. dianatnejadii) from Iran were characterized by GC‐FID and GC/MS analyses. The oil yield was found to be between 0.6 and 1.1% (v/w). In total, 49 compounds, accounting for 96.6–99.7% of the oil compositions, were identified. Aromatic compounds, represented mainly by methyl chavicol (33.6–49.1%), and oxygenated monoterpenes, represented by linalool (14.4–39.3%), were the main components in all essential oils. Monoterpene hydrocarbons were present in the essential oils of all accessions of the purpurascens variety, whereas they were completely absent in those of the dianatnejadii variety, indicating that monoterpene hydrocarbons might be considered as marker constituents of the purpurascens variety. The chemotaxonomic value of the essential‐oil compositions was discussed according to the results of the cluster analysis (CA). The CA showed a clear separation of the O. basilicum var. purpurascens accessions and the O. basilicum var. dianatnejadii accessions, although the data showed no major chemotype variation between the studied varieties. Indeed, the CA revealed only one principal chemotype (methyl chavicol/linalool) for both varieties. In conclusion, GC/MS analyses in combination with CA showed to be a flexible and reliable method for the characterization of the chemical profiles of different varieties of Ocimum basilicum L. 相似文献
289.
Shiau TP Turtle ED Francavilla C Alvarez NJ Zuck M Friedman L O'Mahony DJ Low E Anderson MB Najafi RR Jain RK 《Bioorganic & medicinal chemistry letters》2011,21(10):3025-3028
Antimicrobial resistance against many known therapeutics is on the rise. We examined derivatives of 3-chlorooxazolidin-2-one 1a (X = H) as antibacterial and antifungal agents. The key findings were that the activity and apparent in vitro cytotoxicity could be controlled by the substitution of charged solubilizers at the 4- and 5- positions. These changes both significantly increase the antifungal potency and decrease cytotoxicity. Particularly effective were trialkylammonium groups which led to 400- to 600-fold increases in the antifungal therapeutic index when compared to their unsubstituted counterparts. 相似文献
290.
Fariborz Khajali Maryam Heydary Moghaddam Hossein Hassanpour 《International journal of biometeorology》2014,58(6):1175-1179
An experiment was carried out to examine the effects of supplemental dietary arginine (ARG) on growth, hypertensive response, and gut function in broilers reared at high altitude (2,100 m). A total of 120 day-old male broilers (Cobb 500) were divided equally into two treatment groups. Treatments included a control basal diet composed of corn and soybean meal and an experimental diet to which an l-ARG supplement was added at 10 g/kg. The trial lasted for 42 days. There were no treatment differences with regard to feed intake, body weight gain, or feed conversion ratio. However ARG supplementation did increase the plasma concentration of nitric oxide, a potent vasodilator (P?<?0.05), and attenuated indices of pulmonary hypertension as reflected by reductions in the hematocrit and the right to total ventricular weight ratio (P?<?0.05). Significantly enhanced intestinal mucosal development was observed in broilers receiving ARG supplement when compared with controls (P?<?0.05), suggesting that ARG supplementation increased the absorptive surface area of the jejunum and ileum. In conclusion, broiler diets supplemented with ARG beneficially improved pulmonary hemodynamics and appeared to enhance gut function. 相似文献