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61.
Majid Shahbazi Hamid Ebadi Davood Fathi Danial Roshandel Mana Mahamadhoseeni Azam Rashidbaghan Narges Mahammadi Mahammad Reza Mahammadi Mahdi Zamani 《Cellular and molecular neurobiology》2009,29(8):1205-1209
The 32-base pair deletion on the C–C chemokine receptor 5 gene (CCR5-delta32) is known as a protective allele against immune
system disorders. We have studied this variation in Iranian multiple sclerosis (MS) patients and healthy controls. DNA samples
were prepared from the whole blood of 254 patients with MS and 380 healthy controls. We amplified the fragment including the
CCR5-delta32 polymorphism and visualized the products in a documentation system after agarose gel electrophoresis. Data were
analysed using one-way ANOVA and Fisher’s exact tests with SPSS-v13 and STATA-v8 software. The delta32 allele was more frequent
in MS patients when compared with controls (OR = 2.3, P < 0.0001). Also, we found a significant difference in the frequency of the delta32/delta32 genotype among patients and controls
(OR = 7.4, P < 0.001). The mean age at onset and progression index was not significantly different between patients with various genotypes.
According to our study, the delta32 allele of the CCR5 gene might be a predisposing factor for MS development in the Iranian
population. However, there were no associations between this polymorphism and the clinical course of the disease in this study. 相似文献
62.
Mannan Hajimahmoodi Mohammad Ali Faramarzi Najmeh Mohammadi Neda Soltani Mohammad Reza Oveisi Nastaran Nafissi-Varcheh 《Journal of applied phycology》2010,22(1):43-50
Antioxidant activities of both cells and extracellular substances were evaluated in 12 soil-isolated strains of microalgae
according to FRAP and DPPH-HPLC assays. Their total phenolic contents were also determined by Folin–Ciocalteu method. Extractions
were performed with hexane, ethyl acetate, and water. The results of FRAP assay showed that algal cells contained considerable
amounts of antioxidants from 0.56 ± 0.06 to 31.06 ± 4.00 μmol Trolox g−1 for Microchaete tenera hexane extract and Chlorella vulgaris water extract, respectively. In water fractions of extracellular substances, the antioxidants were from 1.30 ± 0.15 μmol
Trolox g−1 for Fischerella musicola to 73.20 ± 0.16 μmol Trolox g−1 for Fischerella ambigua. Also, DPPH-HPLC assay represented high antioxidant potential of water fractions. The measured radical-scavenging activities
of the studied microalgae were at least 0.15 ± 0.02 in Nostoc ellipsosporum cell mass to a maximum of 109.02 ± 8.25 in C. vulgaris extracellular substance. The amount of total phenolic contents varied in different strains of microalgae and ranged from
zero in hexane extract to 19.15 ± 0.04 mg GAE g−1 in C. vulgaris extracellular water fraction. Significant correlation coefficients between two measured parameters indicated that phenolic
compounds were a major contributor to the microalgal antioxidant capacities. 相似文献
63.
Human mesenchymal stem cells (MSCs) derived from adult tissues have been considered a candidate cell type for cell‐based tissue engineering and regenerative medicine. These multipotent cells have the ability to differentiate along several mesenchymal lineages and possibly along non‐mesenchymal lineages. MSCs possess considerable immunosuppressive properties that can influence the surrounding tissue positively during regeneration, but perhaps negatively towards the pathogenesis of cancer and metastasis. The balance between the naïve stem state and differentiation is highly dependent on the stem cell niche. Identification of stem cell niche components has helped to elucidate the mechanisms of stem cell maintenance and differentiation. Ultimately, the fate of stem cells is dictated by their microenvironment. In this review, we describe the identification and characterization of bone marrow‐derived MSCs, the properties of the bone marrow stem cell niche, and the possibility and likelihood of MSC involvement in cancer progression and metastasis. J. Cell. Physiol. 222: 268–277, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
64.
We describe a boy with chronic abdominal pain, nausea and vomiting, and weight loss. The imaging was compatible with Takayasu's arteritis. Chronic mesenteric ischemia was the etiology of the patient's symptoms. 相似文献
65.
Functional spliceosomal A complexes can be assembled in vitro in the absence of a penta-snRNP 总被引:3,自引:1,他引:2
Two different models currently exist for the assembly pathway of the spliceosome, namely, the traditional model, in which spliceosomal snRNPs associate in a stepwise, ordered manner with the pre-mRNA, and the holospliceosome model, in which all spliceosomal snRNPs preassemble into a penta-snRNP complex. Here we have tested whether the spliceosomal A complex, which contains solely U1 and U2 snRNPs bound to pre-mRNA, is a functional, bona fide assembly intermediate. Significantly, A complexes affinity-purified from nuclear extract depleted of U4/U6 snRNPs (and thus unable to form a penta-snRNP) supported pre-mRNA splicing in nuclear extract depleted of U2 snRNPs, whereas naked pre-mRNA did not. Mixing experiments with purified A complexes and naked pre-mRNA additionally confirmed that under these conditions, A complexes do not form de novo. Thus, our studies demonstrate that holospliceosome formation is not a prerequisite for generating catalytically active spliceosomes and that, at least in vitro, the U1 and U2 snRNPs can functionally associate with the pre-mRNA, prior to and independent of the tri-snRNP. The ability to isolate functional spliceosomal A complexes paves the way to study in detail subsequent spliceosome assembly steps using purified components. 相似文献
66.
67.
Dr. Feyzi Sinan Tokalı Dr. Parham Taslimi Dr. Burak Tuzun Dr. Ahmet Karakuş Dr. Nastaran Sadeghian Prof. Dr. İlhami Gulçin 《化学与生物多样性》2023,20(10):e202301134
Quinazolinones, which represent an important part of nitrogen-containing six-membered heterocyclic compounds, are frequently used in drug design due to their wide biological activity properties. Therefore, the novel quinazolinones were synthesized from the reaction of acylated derivatives of 4-hydroxy benzaldehyde with 3-amino-2-alkylquinazolin-4(3H)-ones with good yields (85–94 %) and their structures were characterized using Fourier-transform Infrared (FT-IR), Nuclear Magnetic Resonance (1H-NMR, 13C-NMR), and High-Resolution Mass Spectroscopy (HR-MS). As the application of the synthesized compounds, their inhibition properties of the synthesized compounds on α-Glucosidase (α-Glu), Acetylcholinesterase (AChE), Butyrylcholinesterase (BChE), and Carbonic anhydrase I–II (hCA I–II) metabolic enzymes were investigated. All compounds showed inhibition at nanomolar level with the Ki values in the range of 12.73±1.26–93.42±9.44 nM for AChE, 8.48±0.92–25.84±2.59 nM for BChE, 66.17±5.16–818.06±44.41 for α-Glu, 2.56±0.26–88.23±9.72 nM for hCA I, and 1.68±0.14–85.43±7.41 nM for hCA II. Molecular docking study was performed to understand the interactions of the most potent compounds with corresponding enzymes. Also, absorption, distribution, metabolism, excretion, and toxicity (ADME/T) properties of the compounds were investigated. 相似文献
68.
M. Izadinia M. Nobakht F. Khajali M. Faraji F. Zamani D. Qujeq I. Karimi 《Animal Feed Science and Technology》2010,155(2-4):194-200
As canola meal protein (CMP) has a lower arginine (Arg) content than soybean meal protein (SBMP), the main objective of this study was to investigate if replacing SBMP by CMP affected the incidence of pulmonary hypertension and ascites. Two hundred and seventy broiler chicks (Ross 308) were used to evaluate the effect of replacing CMP at proportionally 0, 0.5, and 1 for SBMP in a complete randomized block design, as mentioned in the Statistical analysis section (dietary treatments designated as CMP0, CMP0.5, and CMP1, respectively). The experiment was carried out on litter flooring from 6 to 42 days of age. The results indicate that broiler performance (body weight gain, feed intake, and feed conversion ratio) was significantly (P<0.05) impaired in the CMP1 group at 6–21 days but not at 21–42 days. Inclusion of canola meal (CM) in the diet significantly increased ascites and total mortality (P<0.05) and caused a decrease in the serum nitric oxide (NO) concentration with a concomitant increase (P<0.05) in the right ventricular weight ratio (RV/TV). Haematocrit, circulatory triiodothyronine and thyroxine thyroid hormone concentrations and serum alkaline phosphatase activity were unaffected by dietary treatments. In conclusion, the results of this study indicate that substitution of CMP for SBMP was associated with pulmonary hypertension (i.e., higher RV/TV) and ascites mortality in broiler chickens. 相似文献
69.
Denis Chemla Isabelle Antony Karen Zamani Alain Nitenberg 《Journal of applied physiology》2005,99(6):2278-2284
The aim of our study was twofold: 1) to establish a mathematical link between mean aortic pressure (MAP) and systolic (SAP) and diastolic aortic pressures (DAP) by testing the hypothesis that either the geometric mean or the harmonic mean of SAP and DAP were reliable MAP estimates; and 2) to critically evaluate three empirical formulas recently proposed to estimate MAP. High-fidelity pressures were recorded at rest at the aortic root level in controls (n = 31) and in subjects with various forms of cardiovascular diseases (n = 108). The time-averaged MAP and the pulse pressure (PP = SAP - DAP) were calculated. The MAP ranged from 66 to 160 mmHg [mean = 107.9 mmHg (SD 18.2)]. The geometric mean, i.e., the square root of the product of SAP and DAP, furnished a reliable estimate of MAP [mean bias = 0.3 mmHg (SD 2.7)]. The harmonic mean was inaccurate. The following MAP formulas were also tested: DAP + 0.412 PP (Meaney E, Alva F, Meaney A, Alva J, and Webel R. Heart 84: 64, 2000), DAP + 0.33 PP + 5 mmHg [Chemla D, Hébert JL, Aptecar E, Mazoit JX, Zamani K, Frank R, Fontaine G, Nitenberg A, and Lecarpentier Y. Clin Sci (Lond) 103: 7-13, 2002], and DAP + [0.33 + (heart rate x 0.0012)] PP (Razminia M, Trivedi A, Molnar J, Elbzour M, Guerrero M, Salem Y, Ahmed A, Khosla S, Lubell DL. Catheter Cardiovasc Interv 63: 419-425, 2004). They all provided accurate and precise estimates of MAP [mean bias = -0.2 (SD 2.9), -0.3 (SD 2.7), and 0.1 mmHg (SD 2.9), respectively]. The implications of the geometric mean pressure strictly pertained to the central (not peripheral) level. It was demonstrated that the fractional systolic (SAP/MAP) and diastolic (DAP/MAP) pressures were reciprocal estimates of aortic pulsatility and that the SAP times DAP product matched the total peripheral resistance times cardiac power product. In conclusion, although the previously described thumb-rules applied, the "geometric MAP" appears more valuable as it established a simple mathematical link between the steady and pulsatile component of aortic pressure. 相似文献
70.
Jackson RW Osborne K Barnes G Jolliff C Zamani D Roll B Stillings A Herzog D Cannon S Loveland S 《Applied and environmental microbiology》2000,66(1):453-454
A new SimPlate heterotrophic plate count (HPC) method (IDEXX Laboratories, Westbrook, Maine) was compared with the pour plate method at 35 degrees C for 48 h. Six laboratories tested a total of 632 water samples. The SimPlate HPC method was found to be equivalent to the pour plate method by regression analysis (r = 0. 95; y = 0.99X + 0.06). 相似文献