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排序方式: 共有196条查询结果,搜索用时 15 毫秒
31.
Polysaccharide-protein gums are complex polymers with many applications in emulsion and emulsion-based products. It is crucial to enclose a concept on understanding of functional properties of polysaccharide-protein biopolymer in order to select the appropriate one based on the application scope. The main objective of the current study was to investigate the effect of three extraction variables on the surface activity, particle uniformity, apparent viscosity, and protein content of a natural polysaccharide-protein biopolymer from durian fruit seed. Three extraction variables namely water: seed (W/S) ratio (20:1?C60:1), temperature (25.0?C85.0?°C) and pH (4.0?C10.0) were considered as independent variables. The results indicated that durian seed gum induced very low viscosity (0.93?C4.98?mPa.s) with pseudoplastic rheological behavior in the aqueous system. The current study revealed that the extraction variables had the most significant (p?<?0.05) effect on the emulsifying surface activity of the natural biopolymer from durian fruit seed. This might be due to the significant (p?<?0.05) effect of the proteineous constituent present in the chemical structure of the biopolymer from durian fruit seed. The aqueous extraction variables showed the most and least significant (p?<?0.05) effect on the specific surface area and protein content, respectively. Among all extraction variables, W/S ratio and pH exhibited the highest and lowest significant (p?<?0.05) effect on the physicochemical and functional properties of the natural biopolymer from durian fruit seed. 相似文献
32.
Bahrami G Mohammadi B Sisakhtnezhad S 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2008,864(1-2):168-172
A sensitive and rapid method is described for determination of clopidogrel carboxylic acid (CCA), the inactive metabolite of anti platelet agent, clopidogrel, in human serum. The analytical procedure involves liquid-liquid extraction of the analyte and an internal standard (phenytoin) with ethyl acetate. A mobile phase consisting of 0.05 M phosphate buffer containing triethylamine (0.5 mL/L; pH 5.7) and acetonitrile (56:44 v/v) was used and chromatographic separation was achieved using C18 analytical column at detector wavelength of 220 nm. The calibration curves were linear over a concentration range of 0.05-10 microg/mL of CCA in human serum. The total run time of analysis was 5.5 min and the lower limits of detection (LOD) and quantification (LOQ) were 0.02 and 0.05 microg/mL, respectively. The method validation was carried out in terms of specificity, sensitivity, linearity, precision, accuracy and stability. The validated method was applied in a randomized cross-over bioequivalence study of two different clopidogrel preparations in 24 healthy volunteers. 相似文献
33.
Bahrami G Mohammadi B Kiani A 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2008,872(1-2):38-42
A new straightforward method based on cloud-point extraction (CPE) has been developed, optimized and validated for the determination of venlafaxine in human plasma by reversed-phase high-performance liquid chromatography with fluorescence detection. The non-ionic surfactant Triton X-114 (polyethylene glycol tert-octylphenyl ether) was chosen as the extract solvent. Separation was obtained using a reversed-phase Diamonsil column (C(18), 250mmx4.6mm I.D., 5mum) and a mobile phase composed of acetonitrile-phosphate buffer solution (pH 3.0)-triethylamine (33.5:66.5:0.4). Fluorescence detection was used (lambda(ex) 276nm, lambda(em) 598nm). Maprotiline was used as the internal standard. Under the optimum conditions, the linear range of venlafaxine in human plasma was 10-800ngmL(-1) (r(2)=0.9995). The limit of detection (LOD) was less than 2ngmL(-1) (S/N=3) and the limit of quantification (LOQ) was less than 10ngmL(-1) (S/N=10). The method was successfully applied for the evaluation of pharmacokinetic profiles of venlafaxine capsules in nine healthy volunteers. 相似文献
34.
Mahboobeh Ziaei Mostafa Motallebi Mohammad Reza Zamani Nasim Zarin Panjeh Zahra Moghaddassi Jahromi 《Journal of plant biochemistry and biotechnology.》2016,25(4):358-366
Canola (Brassica napus L.), an agro-economically important crop in the world, is sensitive to many fungal pathogens. One strategy to combat fungal diseases is genetic engineering through transferring genes encoding the pathogenesis-related (PR) proteins such as chitinase which cause the chitin degradation of fungal cell wall. Chitinase Chit42 from Trichoderma atroviride (PTCC5220) plays an important role in biocontrol and has high antifungal activity against a wide range of phytopathogenic fungi. This enzyme lacks a chitin binding domain (ChBD) which is involved in binding activity to insoluble chitin. In the present study, we investigated the effect of chitin binding domain fused to Chit42 when compared with native Chit42. These genes were over-expressed under the CaMV35S promoter in B. napus, R line Hyola 308. Transformation of cotyledonary petioles was achieved by pBISM2 and pBIKE1 constructs containing chimeric and native Chit42 genes respectively, via Agrobacterium method. The insertion of transgenes in T0 generation was verified through polymerase chain reaction (PCR) and Southern blot analysis. Antifungal activity of expressed chitinase in transgenic plants was also investigated by bioassays. The transgenic canola expressing chimeric chitinase showed stronger inhibition against phytopathogenic fungi that indicates the role of chitin binding domain. 相似文献
35.
Chartier-Harlin MC Dachsel JC Vilariño-Güell C Lincoln SJ Leprêtre F Hulihan MM Kachergus J Milnerwood AJ Tapia L Song MS Le Rhun E Mutez E Larvor L Duflot A Vanbesien-Mailliot C Kreisler A Ross OA Nishioka K Soto-Ortolaza AI Cobb SA Melrose HL Behrouz B Keeling BH Bacon JA Hentati E Williams L Yanagiya A Sonenberg N Lockhart PJ Zubair AC Uitti RJ Aasly JO Krygowska-Wajs A Opala G Wszolek ZK Frigerio R Maraganore DM Gosal D Lynch T Hutchinson M Bentivoglio AR Valente EM Nichols WC Pankratz N 《American journal of human genetics》2011,(3):140-406
Genome-wide analysis of a multi-incident family with autosomal-dominant parkinsonism has implicated a locus on chromosomal region 3q26-q28. Linkage and disease segregation is explained by a missense mutation c.3614G>A (p.Arg1205His) in eukaryotic translation initiation factor 4-gamma (EIF4G1). Subsequent sequence and genotype analysis identified EIF4G1 c.1505C>T (p.Ala502Val), c.2056G>T (p.Gly686Cys), c.3490A>C (p.Ser1164Arg), c.3589C>T (p.Arg1197Trp) and c.3614G>A (p.Arg1205His) substitutions in affected subjects with familial parkinsonism and idiopathic Lewy body disease but not in control subjects. Despite different countries of origin, persons with EIF4G1 c.1505C>T (p.Ala502Val) or c.3614G>A (p.Arg1205His) mutations appear to share haplotypes consistent with ancestral founders. eIF4G1 p.Ala502Val and p.Arg1205His disrupt eIF4E or eIF3e binding, although the wild-type protein does not, and render mutant cells more vulnerable to reactive oxidative species. EIF4G1 mutations implicate mRNA translation initiation in familial parkinsonism and highlight a convergent pathway for monogenic, toxin and perhaps virally-induced Parkinson disease. 相似文献
36.
Nafiseh Yousefi Abdolkarim Chehregani Behrouz Malayeri Bahareh Lorestani Mehrdad Cheraghi 《Biological trace element research》2011,140(3):368-376
Excessive amounts of heavy metals adversely affect plant growth and development. Whereas some regions naturally contain high
levels of heavy metals, anthropogenic release of heavy metals into the environment continuously increases soil contamination.
Preliminary studies have shown that Chenopodium botrys can grow in some heavy metal contaminated soils and is a high accumulator plant species for Cu and moderately accumulator
plant species for Fe, Mn, and Zn, thus, was considered as an important species in this study. Based on that, in this species,
we studied the individual effects of heavy metals on the formation, development, and structure of anther and pollen. To achieve
this purpose, surrounding area of Hame-Kasi iron and copper mine (Hamedan, Iran) was chosen as a polluted area where the amount
of some heavy metals was several times higher than the natural soils. Flowers and young pods were removed from non-polluted
and polluted plants, fixed in FAA 70, and subjected to developmental studies. Analysis of anther development in plants from
contaminated sites showed general similarities in the pattern of pollen formation with those from non-polluted ones, but also
deviation from typical form of major stages of anther and pollen development was seen in plants from polluted ones. Stabilizing
of tapetum layer, increasing in tapetum layer numbers, thickening callose wall in the microspore mother cell stage, changing
the anther shape, and decreasing the size of anther were the effects of heavy metals. Reduction of pollen number was also
seen in the plants collected from polluted area. 相似文献
37.
Mehdi Hosseini-Mazinani Roberto Mariotti Bahareh Torkzaban Massoma Sheikh-Hassani Saeedeh Ataei Nicolò G. M. Cultrera Saverio Pandolfi Luciana Baldoni 《PloS one》2014,9(4)
Background
Olive trees (Olea europaea subsp. europaea var. europaea) naturally grow in areas spanning the Mediterranean basin and towards the East, including the Middle East. In the Iranian plateau, the presence of olives has been documented since very ancient times, though the early history of the crop in this area is shrouded in uncertainty.Methods
The varieties presently cultivated in Iran and trees of an unknown cultivation status, surviving under extreme climate and soil conditions, were sampled from different provinces and compared with a set of Mediterranean cultivars. All samples were analyzed using SSR and chloroplast markers to establish the relationships between Iranian olives and Mediterranean varieties, to shed light on the origins of Iranian olives and to verify their contribution to the development of the current global olive variation.Results
Iranian cultivars and ecotypes, when analyzed using SSR markers, clustered separately from Mediterranean cultivars and showed a high number of private alleles, on the contrary, they shared the same single chlorotype with the most widespread varieties cultivated in the Mediterranean.Conclusion
We hypothesized that Iranian and Mediterranean olive trees may have had a common origin from a unique center in the Near East region, possibly including the western Iranian area. The present pattern of variation may have derived from different environmental conditions, distinct levels and selection criteria, and divergent breeding opportunities found by Mediterranean and Iranian olives.These unexpected findings emphasize the importance of studying the Iranian olive germplasm as a promising but endangered source of variation. 相似文献38.
Purpose
To investigate presence, location and functional role of calcium-activated chloride channel (CaCC) Anoctamin-1 (Ano1) in rat urinary bladder.Materials and Methods
Bladders from 3 week old Wistar rats were studied. End-point PCR on total mRNA was used to assess the expression of Ano1. Immunofluorescent labelling of whole mount bladder tissue imaged with confocal microscope allowed localization of Ano1 and vimentin immunopositive cells. The effects of CaCC blockers: niflumic acid (NFA) (3,10,30 µM) and 5-Nitro-2-(3-phenylpropylamino)benzoic acid (NPPB) (10, 30 µM) on spontaneous phasic contractile activity of intact (with mucosa) and denuded (without mucosa) detrusor strips were measured under isometric tension in organ baths (n = 141, N = 60).Results
Ano1 expression was found at mRNA level in mucosa and detrusor layers. Confocal microscopy revealed presence of Ano1 immunopositive cells in mucosa and in detrusor layers; a subpopulation of vimentin positive cells expressed Ano1. Both chloride channel blockers reduced the amplitude and frequency of phasic contractions in denuded and intact strips.Conclusions
Ano1 is expressed in rat urinary bladder and is present in cells sharing markers with interstitial cells. CaCC blockers reduced phasic activity of the bladder tissue. Ano1 is expressed in the bladder and plays a role in its spontaneous phasic contractile activity. 相似文献39.
Bahareh Bahmani Mehryar Habibi Roudkenar Raheleh Halabian Ali Jahanian-Najafabadi Fatemeh Amiri Mohammad Ali Jalili 《Cell stress & chaperones》2014,19(5):685-693
The regenerative potential of mesenchymal stem cells (MSCs) is impaired by cellular senescence, a multi factorial process that has various functions. However, pathways and molecules involved in senescence have not been fully identified. Lipocalin 2 (Lcn2) has been the subject of intensive research, due to its contribution to many physiological and pathophysiological conditions. The implication of Lcn2 has been reported in many conditions where senescence also occurs. In the present study, we evaluated the role of Lcn2 in the occurrence of senescence in human bone marrow-derived mesenchymal stem cells (hB-MSCs) under oxidative conditions. When hB-MSCs were genetically engineered to over-express Lcn2 (MSC-Lcn2) and exposed to H2O2, the proliferation rate of the cells increased. However, the number of colonies and the number of cells that made up each colony in both MSC-V and MSC-Lcn2 cells decreased compared to those cultivated under normal conditions. Our results revealed that over-expression of recombinant Lcn2 in hB-MSCs decreases senescence induced by H2O2 treatment. Senescent cells were observed in aged hB-MSCs; however, no alteration in the expression level of Lcn2 was detected compared to earlier passages. Finally, a higher amount of Lcn2 protein was detected in the plasma of the elderly than in young people. Our findings suggest that Lcn2 might restore the health and regeneration potential of MSCs by decreasing senescence. 相似文献
40.
Arezou Sayad Soudeh Ghafouri-Fard Bahareh Shams Shahram Arsang-Jang Leila Gholami Mohammad Taheri 《Journal of cellular physiology》2020,235(12):9568-9576
Periodontitis is a complex disorder that affects a large number of human beings from different ethnic groups. This condition has been associated with dysregulation of a number of genes, among them are long noncoding RNAs (lncRNAs). In the current study, we assessed the expression of four lncRNAs (BDNF-AS, MIAT, MIR137HG, and PNKY) as well as BDNF in the peripheral blood and gingival tissues obtained from patients with periodontitis and healthy subjects. The expression of BDNF was significantly lower in blood samples of male patients with periodontitis compared with male controls (posterior β of RE = −4.754, p = .048). However, there was no significant difference in the expression of BDNF in tissue samples from the cases and controls. The expression of BDNF-AS was significantly lower in the tissue samples of patients compared with control tissue samples (posterior β of RE = −2.151, p = .019). Such an expression difference was detected between male subgroups as well (posterior β of RE = −3.679, p = .009). However, expression of this lncRNA was not different in blood samples obtained from patients compared with healthy subjects. The expression of PNKY was significantly higher in tissue samples obtained from female patients compared with sex-matched controls (posterior β of RE = 6.23, p = .037). Blood levels of this lncRNA were not different between cases and controls. There was no significant difference either in the tissue expression or in blood expression of MIR137HG or MIAT between cases and controls. The current study indicates the putative role of BDNF, BDNF-AS, and PNKY in the pathophysiology of periodontitis and potentiates these genes as candidates for functional studies. 相似文献