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51.
Mucins are related to infectious and non-infectious diseases in Veterinary and Human Medicine. MUC1 mucin is a transmembrane glycoprotein expressed on the apical surface of human epithelia while MUC5AC is the predominant secreted mucin expressed in human gastric epithelium and goblet cells of lung and eyes. MUC5AC C-terminus cysteine rich regions and the cytoplasmic tail of MUC1 domains are conserved among several mammalian species. Objective: to compare the expression of MUC1 and MUC5AC mucins in mammalian epithelia. CT33 anti-MUC1 cytoplasmic tail (MUC1CT) polyclonal antibody and 45M1 anti-MUC5AC monoclonal antibody were employed. By immunohistochemistry, MUC1CT was expressed in most tissues while MUC5AC was restricted to gastric surface epithelium and goblet cells from trachea and lung. By western blot, MUC1CT showed a band at approximately 35 kDa in most tissues; MUC5AC revealed bands at >180 kDa in stomach and lung secretions from rat, cat, pig and cow. When rat MUC5AC was immunoprecipitated, a band at about 180 kDa was obtained. 相似文献
52.
Ramos MV Aguiar VC da Silva Xavier AA Lima MW Bandeira GP Etchells JP Nogueira NA Alencar NM 《Fitoterapia》2006,77(4):251-256
Soluble proteins from the latex of Calotropis procera (LP) were investigated in vitro and in vivo for digestibility as the latex has previously been shown to produce considerable toxic effects on animals. The latex is also an important biologically active compound that displays antiinflammatory and antidiarrhea properties. The proteins were digested by the action of trypsin, pepsin or chemotrypsin as revealed by gel filtration and SDS-PAGE analysis. Furthermore, the full LP digestion was easily achieved by protease treatment. Rabbit polyclonal antibodies raised against LP failed to detect cross-reactive molecules in fecal material of experimental rats following 35 consecutive days of LP consumption in water. Similar patterns of electrophoresis were observed for the negligible amounts of protein observed in the fecal extracts of control and test animals. No death or toxic effects were observed among animals. Taken together these results suggest that harmful and toxic effects on animals of the latex from C. procera are present in its rubber and low molecular weight fractions rather than its protein content. 相似文献
53.
Baroni MV Nores ML Díaz Mdel P Chiabrando GA Fassano JP Costa C Wunderlin DA 《Journal of agricultural and food chemistry》2006,54(19):7235-7241
We report the evaluation of the floral origin of honey by analysis of its volatile organic compounds (VOCs) profile, joined with the use of combined pattern recognition techniques. Honey samples, from five floral origins, were analyzed by headspace solid-phase microextraction-gas chromatography-mass spectrometry, selecting 35 VOCs out of the entire profiles, which were analyzed by hierarchical cluster analysis (HCA), stepwise discriminant analysis (SDA), and K-nearest-neighbor (KNN). Both HCA and SDA were used as exploratory tools to select a group of VOCs representing similitude and differences among studied origins. Thus, six out of 35 VOCs were selected, verifying their discriminating power by KNN, which afforded 93% correct classification. Therefore, we drastically reduced the amount of compounds under consideration but kept a good differentiation between floral origins. Selected compounds were identified as octanal, benzeneacetaldehyde, 1-octanol, 2-methoxyphenol, nonanal, and 2-H-1-benzopyran-2-one. The analysis of VOC profiles, coupled to HCA, SDA, and KNN, provides a feasible alternative to evaluate the botanical source of honey. 相似文献
54.
The mechanical properties and responses of cells to external stimuli (including drugs) are closely connected to important phenomena such as cell spreading, motility, activity, and potentially even differentiation. Here, reversible changes in the viscoelastic properties of surface-attached fibroblasts were induced by the cytoskeleton-perturbing agent cytochalasin D, and studied in real-time by the quartz crystal microbalance with dissipation (QCM-D) technique. QCM-D is a surface sensitive technique that measures changes in (dynamically coupled) mass and viscoelastic properties close to the sensor surface, within a distance into the cell that is usually only a fraction of its size. In this work, QCM-D was combined with light microscopy to study in situ cell attachment and spreading. Overtone-dependent changes of the QCM-D responses (frequency and dissipation shifts) were first recorded, as fibroblast cells attached to protein-coated sensors in a window equipped flow module. Then, as the cell layer had stabilised, morphological changes were induced in the cells by injecting cytochalasin D. This caused changes in the QCM-D signals that were reversible in the sense that they disappeared upon removal of cytochalasin D. These results are compared to other cell QCM-D studies. Our results stress the combination of QCM-D and light microscopy to help interpret QCM-D results obtained in cell assays and thus suggests a direction to develop the QCM-D technique as an even more useful tool for real-time cell studies. 相似文献
55.
Ravoori S Vadhanam MV Aqil F Gupta RC 《Journal of agricultural and food chemistry》2012,60(22):5547-5555
We previously demonstrated the protective effects of blueberry (BB) and black raspberry (BRB) supplemented at 2.5% dose in an ACI rat mammary tumor model. Here, we assessed a dose-related alteration in tumor indices with diet supplemented with 5% BB or BRB powder. The diet was well tolerated. Tumor palpation from 12 weeks revealed first tumor appearance by 84 days in the control group, that was delayed by 24 and 39 days with the BB and BRB diets, respectively (p = 0.04). Ellagic acid detected in the plasma of rats fed the BRB diet was in the range of 96.6-294.2 ng/mL. While the BB diet showed better efficacy in reducing mammary tissue proliferation and tumor burden, tumor latency was delayed efficiently by BRB. Furthermore, BB was effective in downregulating CYP1A1 expression, while BRB downregulated ERα expression effectively. Distinct anticarcinogenic effects of the two berries correspond to their distinct phytochemical signatures. 相似文献
56.
Schulmerich MV Walsh MJ Gelber MK Kong R Kole MR Harrison SK McKinney J Thompson D Kull LS Bhargava R 《Journal of agricultural and food chemistry》2012,60(33):8097-8102
The soybean industry requires rapid, accurate, and precise technologies for the analyses of seed/grain constituents. While the current gold standard for nondestructive quantification of economically and nutritionally important soybean components is near-infrared spectroscopy (NIRS), emerging technology may provide viable alternatives and lead to next generation instrumentation for grain compositional analysis. In principle, Raman spectroscopy provides the necessary chemical information to generate models for predicting the concentration of soybean constituents. In this communication, we explore the use of transmission Raman spectroscopy (TRS) for nondestructive soybean measurements. We show that TRS uses the light scattering properties of soybeans to effectively homogenize the heterogeneous bulk of a soybean for representative sampling. Working with over 1000 individual intact soybean seeds, we developed a simple partial least-squares model for predicting oil and protein content nondestructively. We find TRS to have a root-mean-standard error of prediction (RMSEP) of 0.89% for oil measurements and 0.92% for protein measurements. In both calibration and validation sets, the predicative capabilities of the model were similar to the error in the reference methods. 相似文献
57.
Production of renewable fuels and chemicals from lignocellulosic feedstocks requires an efficient pretreatment technology to allow ready access of polysaccharides for cellulolytic enzymes during saccharification. The effect of pretreatment on wheat straw through a low-temperature and low-pressure soaking aqueous ammonia (SAA) process was investigated in this study using Fourier transform infrared (FTIR), pyrolysis-gas chromatography/mass spectroscopy (Py-GC/MS), solid and liquid state nuclear magnetic resonance (NMR), and thermogravimetry/differential thermogravimetry (TG/DTG) to demonstrate the changes in lignin, hemicellulose, and cellulose structure. After treatment of 60 mesh wheat straw particles for 60 h with 28-30% ammonium hydroxide (1:10 solid/liquid) at 50 °C, sugar recovery increased from 14% (untreated) to 67% (SAA treated). The FTIR study revealed a substantial decrease in absorbance of lignin peaks. Solid and liquid state NMR showed minimal lignin structural changes with significant compositional changes. Activation energy of control and pretreated wheat straw was calculated according to the Friedman and ASTM methods and found to be decreased for SAA-treated wheat straw, from 259 to 223 kJ/mol. The SAA treatment was shown to remove significant amounts of lignin without strongly affecting lignin functional groups or structure. 相似文献
58.
Whittemore JC Marcum BA Mawby DI Coleman MV Hacket TB Lappin MR 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2011,25(4):818-824
Background: Microalbuminuria and C‐reactive protein (CRP) are predictors of morbidity and survival in critically ill human patients. Hypothesis/Objectives: To evaluate results of microalbuminuria assays (untimed single‐sample urine albumin concentration [U‐ALB] and the urine albumin : creatinine ratio [UACR]), serum CRP, and survival predictor index (SPI2) scores as predictors of survival in critically ill dogs. Animals: Seventy‐eight dogs admitted to intensive care units at University of Tennessee (UT) and Colorado State University (CSU). Methods: Prospective observational study. Critically ill dogs were eligible for enrollment, unless euthanized because of financial constraints. Samples were collected within 3 hours of admission. Spearman's rank‐correlation coefficients were determined for U‐ALB, UACR, CRP, and SPI2. U‐ALB, UACR, CRP, and SPI2 were assessed for associations with 7‐ and 30‐day survival by Mann‐Whitney U‐tests and receiver operating characteristic (ROC) curves. P‐values < .0125 were considered significant. Results: UT (n = 49) and CSU (n = 29) patients did not differ significantly. Forty percent (31/78) of dogs died. SPI2 was inversely correlated with U‐ALB (rs=?0.39, P < .001) and UACR (rs=?0.41, P < .001). CRP was not correlated with SPI2 (P= .019), U‐ALB (P > .1), or UACR (P > .1). U‐ALB and UACR had very high correlation (rs= 0.95, P < .001). SPI2, U‐ALB, and UACR differed significantly for survivors and nonsurvivors. SPI2, U‐ALB, and UACR had areas under the ROC curve (AUC) from 0.68 to 0.74 for survival prediction. Conclusions and Clinical Importance: Albuminuria and SPI2, but not CRP, are associated with survival in critically ill dogs. Suboptimal AUCs limit the value of microalbuminuria testing for clinical risk assessment. Additional studies are necessary to determine the usefulness of microalbuminuria testing in patient risk stratification for prospective research. 相似文献
59.
We examined the principal differences in photosynthetic characteristics between sun and shade foliage and determined the relative importance of biochemical and stomatal limitations during photosynthetic induction. Temperate-zone broadleaf and conifer tree species, ranging widely in shade tolerance, were investigated from one locality in the Czech Republic. The study species included strongly shade-tolerant Abies alba Mill. and Tilia cordata Mill., less shade-tolerant Fagus sylvatica L. and Acer pseudoplatanus L. and sun-demanding Picea abies (L.) Karst. In the fully activated photosynthetic state, sun foliage of all species had significantly higher maximum CO(2) assimilation rates, maximum stomatal conductance and maximum rates of carboxylation than shade foliage. Compared with shade leaves, sun leaves had significantly higher nocturnal stomatal conductances. In all species, shade foliage tended to have higher induction states 60 s after leaf illumination than sun foliage. Sun and shade foliage did not differ in the rate of disappearance of the transient biochemical limitation during the induction phase. Longer time periods were required to reach 90% photosynthetic induction and 90% stomatal induction in sun foliage than in shade foliage of the less shade-tolerant F. sylvatica and A. pseudoplatanus and in sun-demanding P. abies; however, in sun foliage of the strongly shade-tolerant species T. cordata and A. alba, the time needed for photosynthetic induction was similar to, or less than, that for shade foliage. Shade but not sun needles of P. abies and A. alba had significantly slower induction kinetics than the broadleaf tree species. Among species, the sun-demanding P. abies exhibited the shortest stomatal induction times in both sun and shade leaves. Independently of shade tolerance ranking, the transient stomatal and total limitations that characterize photosynthetic induction were relieved significantly earlier in shade foliage than in sun foliage. Sun foliage generally exhibited a hyperbolic photosynthetic induction response, whereas a sigmoidal induction response was more frequent in shade foliage. The different relative proportions of transient biochemical and stomatal limitations during photosynthetic induction in sun and shade foliage indicate an essential role of stomata in photosynthetic limitation during induction, mainly in shade foliage, with a consequent influence on the shape of the photosynthetic induction curve. 相似文献
60.
Cabras P Farris GA Pinna MV Pusino A 《Journal of agricultural and food chemistry》2004,52(26):8053-8056
The fungicide fenhexamid [N-(2,3-dichloro-4-hydroxyphenyl)-1-methylcyclohexanecarboxamide] degraded rapidly by UV or sunlight irradiation, yielding 7-chloro-6-hydroxy-2-(1-methylcyclohexyl)-1,3-benzoxazole (CHB) as a main photoproduct. CHB was isolated, and its effect on alcoholic fermentation of Saccharomyces cerevisiae was studied. The results indicate that the presence of CHB does not affect the extent of alcohol production. After 12 days, the amount of CHB in the fermentation medium decreased by ca. 65%. Only 25% of the missing CHB was recovered unchanged from yeasts, most likely because it was adsorbed on the yeast wall cell. The remaining part degraded during the fermentation process. Glucan and chitin, two potential adsorbents, which constitute yeast cell walls, exhibited affinity for CHB. 相似文献