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51.
52.
Kargar H Moghadam M Mirkhani V Tangestaninejad S Mohammadpoor-Baltork I Nameni I 《Bioorganic & medicinal chemistry letters》2011,21(7):2146-2148
In the present work, dehydrogenation of 2-substituted imidazolines with sodium periodate in the presence of tetraphenylporphyrinatomanganese(III) chloride, [Mn(TPP)Cl], is reported. A wide variety of 2-imidazolines efficiently converted to their corresponding imidazoles by [Mn(TPP)Cl]/NaIO4 catalytic system at room temperature in 1:2, CH3CN/H2O mixture. The effect of reaction parameters such as kind of solvent and catalyst amount was also investigated. 相似文献
53.
Assadi M Salimipour H Akbarzadeh S Nemati R Jafari SM Bargahi A Samani Z Seyedabadi M Sanjdideh Z Nabipour I 《PloS one》2011,6(9):e24240
Background
Patients with multiple sclerosis (MS) are at increased risk of osteoporosis and fractures. Adipose tissue-derived adipokines may play important roles in the osteoimmunology of MS. In order to determine whether omentin-1 and vaspin may be related to bone health in MS patients, we compared circulating levels of these recently identified adipokines, between MS patients and healthy controls.Methods
A total of 35 ambulatory MS patients with relapsing-remitting courses were compared with 38 age- and sex-matched healthy controls. Bone mineral density (BMD) was determined for the lumbar spine (L2–L4) and the proximal femur using dual-energy x-ray absorptiometry. Circulating omentin-1, vaspin, osteocalcin, osteopontin, osteoprotegerin, the receptor activator of nuclear factor-κB ligand, matrix metalloproteinase 9, C-reactive protein and 25-hydroxy vitamin D levels were evaluated by highly specific enzyme-linked immunosorbent assay methods.Results
There was no significant difference between the two groups regarding bone-related cytokines, adipocytokines, and the BMD measurements of patients with MS and the healthy controls. However, in multiple regression analysis, serum omentin-1 levels were positively correlated with BMD at the femoral neck (β = 0.49, p = 0.016), total hip (β = 0.42, p = 0.035), osteopontin (β = 0.42, p = 0.030) and osteocalcin (β = 0.53, p = 0.004) in MS patients. No correlations were found between vaspin, biochemical, and BMD measures in both groups.Conclusions
Elevated omentin-1 serum levels are correlated with BMD at the femoral neck and the serum levels of osteocalcin and osteopontin in MS patients. Therefore, there is crosstalk between adipose tissue and bone in MS. 相似文献54.
Retinoic acid induces mouse bone marrow‐derived CD15+, Oct4+ and CXCR4+ stem cells into male germ‐like cells in a two‐dimensional cell culture system 下载免费PDF全文
55.
Shadab Gharaati Shahram Tangestaninejad Valiollah Mirkhani Iraj Mohammadpoor-Baltork Farshid Kosari 《Inorganica chimica acta》2010,363(9):1995-646
An efficient and selective method for methoxymethylation of alcohols and phenols with formaldehyde dimethyl acetal (FDMA) catalyzed by electron deficient tin(IV)tetraphenylporphyrinato trifluoromethanesulfonate, [SnIV(TPP)(OTf)2], is reported. A variety of primary, secondary and tertiary alcohols as well as phenols were converted to their corresponding methoxymethyl ethers with FDMA in the presence of a high-valent tin(IV) porphyrin. This catalyst can be used for selective methoxymethylation of primary, secondary and tertiary alcohols in the presence of phenols or tertiary alcohols. The present method offers several advantages such as short reaction times, high yields, simple procedure, selectivity and applicability for both alcohols and phenols. 相似文献
56.
Cells in tissues or in experimental cell colonies respond to stimuli in a co-ordinated manner when they are electrically and chemically coupled by gap junctions. These junctions permit the cell-to-cell passage of small molecules, such as inositol tris phosphate (IP(3)) within the colony and are important in co-ordinating tissue activity. This is the only recognised mechanism of direct chemical signalling that does not involve the release of an extracellular messenger between cells. However, the data in this article demonstrates a new mode of intercellular communication. Two potentially important signalling lipids, PIP(2) and ganglioside G-M1 were shown to move between cells in colonies by tracking (i) fluorescent lipids loaded into the plasma membranes of individual cells in a cell colony using a novel micropipette technique and (ii) movement of fluorescent lipids after localised photobleaching. Furthermore, a large protein molecule, cholera toxin B subunit bound to extracellularly facing ganglioside G-M1 was also shown to transfer between cells. The transfer was inhibited by pre-treatment with poly-L-lysine and polyethylenimine, suggesting a role for tight junctions, perhaps by permitting diffusion of lipids and their protein "cargo" across these cell-to-cell contact points. This is a hitherto unsuspected form of molecular signalling within cell colonies and tissues which may have implications for understanding co-ordinated cell colony behaviour. 相似文献
57.
Hossein Mahmoudvand Fatemeh Ezzatkhah Fariba Sharififar Iraj Sharifi Ebrahim Saedi Dezaki 《The Korean journal of parasitology》2015,53(1):21-27
Plants used for traditional medicine contain a wide range of substances that can be used to treat various diseases such as infectious diseases. The present study was designed to evaluate the antileishmanial effects of the essential oil and methanolic extract of Myrtus communis against Leishmania tropica on an in vitro model. Antileishmanial effects of essential oil and methanolic extract of M. communis on promastigote forms and their cytotoxic activities against J774 cells were evaluated using MTT assay for 72 hr. In addition, their leishmanicidal activity against amastigote forms was determined in a macrophage model, for 72 hr. Findings showed that the main components of essential oil were α-pinene (24.7%), 1,8-cineole (19.6%), and linalool (12.6%). Findings demonstrated that M. communis, particularly its essential oil, significantly (P<0.05) inhibited the growth rate of promastigote and amastigote forms of L. tropica based on a dose-dependent response. The IC50 values for essential oil and methanolic extract was 8.4 and 28.9 μg/ml against promastigotes, respectively. These values were 11.6 and 40.8 μg/ml against amastigote forms, respectively. Glucantime as control drug also revealed IC50 values of 88.3 and 44.6 μg/ml for promastigotes and amastigotes of L. tropica, respectively. The in vitro assay demonstrated no significant cytotoxicity in J774 cells. However, essential oil indicated a more cytotoxic effect as compared with the methanolic extract of M. communis. The findings of the present study demonstrated that M. communis might be a natural source for production of a new leishmanicidal agent. 相似文献
58.
Hashemzadeh Segherloo Iraj Najafi Chaloshtory Sajad Naser Murtada D. Yasser Amaal Gh. Tabatabaei Seyedeh Narjes Piette-Lauziere Gabriel Mashtizadeh Amirhossein Elmi Amirmohammad Sedighi Omid Changizi Alieh Hallerman Eric Bernatchez Louis 《Environmental Biology of Fishes》2022,105(9):1251-1260
Environmental Biology of Fishes - Among Tashan cave barb Garra tashanensis inhabiting a small cave in southwest Iran, two mental disc (sucking mouth disc) forms were observed. To assess their... 相似文献
59.
Amiri R Bordbar AK Laurents DV Khosropour AR Mohammadpoor-Baltork I 《International journal of biological macromolecules》2012,50(4):1151-1157
The thermal stability and enzymatic activity of bovine pancreatic ribonuclease A (RNase A) have been investigated in the presence of a homologous series of cationic gemini surfactants (alkanediyl-α,ω-bis(hydroxyethyl methyl hexadecyl ammonium bromide)). UV, circular dichorism and fluorescence spectroscopies have been used for this study. The denaturation curves at various surfactant concentrations were analyzed on basis of a two-transition model to obtain values of T(m) (temperature at the midpoint of denaturation) and ΔH(m) (enthalpy change at T(m)) of each transition. The main conclusion of this study is that these cationic gemini surfactants slightly activate and stabilize RNase A below their critical micelle concentrations at pH 5.0. The cationic gemini surfactant with the shorter spacer interacts more efficiently with RNase A than those with longer spacers. 相似文献
60.