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81.
Combined Expression of Aspergillus nidulans Endoxylanase X24 and Aspergillus oryzae (alpha)-Amylase in Industrial Baker's Yeasts and Their Use in Bread Making 下载免费PDF全文
The Aspergillus nidulans endoxylanase X24 and the Aspergillus oryzae (alpha)-amylase cDNAs were placed under the control of the Saccharomyces cerevisiae actin promoter (pACT1) and introduced into baker's yeast. Bread made with transformants expressing both enzymes (YEpACT-AMY-ACT-X24) showed a 30% increase in volume and reduced firmness in comparison with that produced with a commercial strain. Endoxylanase X24 and (alpha)-amylase seem to act synergistically to improve the quality of bread in terms of volume and density. 相似文献
82.
Plasma glucose kinetics and tissue uptake in brown trout in vivo: effect of an intravascular glucose load 总被引:2,自引:0,他引:2
J. Blasco J. Fernàndez-Borràs I. Marimon A. Requena 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1996,165(7):534-541
The object of the present study was to elucidate whether a glucose load modifies glucose uptake by tissues in brown trout in vivo. By the use of 2-[1,2-3H]-deoxyglucose, plasma glucose disappearance rate and tissue glucose uptake were measured after an intraaortic glucose load of 500 mg·kg-1 (glucose load group) and under normoglycemic conditions (control). We also attempted to determine whether fasting modifies the glucose load disposal (fasted glucose load group). The procedure used to calculate 2-deoxyglucose uptake by tissues was evaluated, and the levels of 2-deoxyglucose uptake were compared with those of 2-deoxyglucose phosphorylation. Uptake and phosphorylation rates were similar in all tissues, except in brain and heart. In all the groups glucose uptake rates were highest in spleen, kidney, brain and gills, and lowest in red muscle, heart and white muscle. However, white muscle was the main site of glucose uptake on a whole tissue basis. The glucose load led to strong, long-lasting hyperglycemia, in spite of the increases observed in plasma insulin levels and in glucose uptake rate by the whole body (control: 4.9 mol·min-1·kg-1; glucose load group: 6.5 mol·min-1·kg-1). This higher rate was due to the higher glucose uptake only in white and red muscles (four- and threefold, respectively). Fasting halved the uptake of glucose by both red and white muscles in the load condition. In consequence the use of exogenous glucose decreased with fasting (fasted glucose load group: 5.1 mol·min-1·kg-1), causing still longer hyperglycemia.Abbreviations
bw
body weight
-
2DG
2-[1,2-3H]-deoxyglucose
-
2DG-P
2-[1,2-3H]-deoxyglucose phosphate
-
dpm
disintegrations per min
-
FGL
fasted glucose load group
-
GL
glucose load group
-
G-6-Pase
glucose-6-phosphatase
-
LG
L-[1-14C]-glucose
-
MS-222
3-aminobenzoic acid ethyl ester methanesulphonate salt 相似文献
83.
A new strict gypsophilous species of Chaenorhinum, Ch. gamezii, is described. It is an annual to perennial species found in extremely arid locations upon Triassic gypsic habitats in the south-eastern Iberian Peninsula. This species has an eglandular heterotrichous indumentum, which is related to Ch. segoviense and Ch. flexuosum. However, Ch. gamezii has a characteristic combination of vegetative and micromorphological features (trichomes and ornamentation of the seeds) that are not present in any other taxon of the genus. Herein, the affinities and differences with related species are studied and discussed. For its differentiation, an original key is presented with comparative figures of indumentum and seeds, and a complete iconography. Knowledge of the species ecology, biogeography, demography and threats is also provided, and according to that, Ch. gamezii should be considered as a critically threatened species (critically endangered, according to IUCN criteria). Future conservation proposals are discussed. 相似文献
84.
José Manuel Fernández‐Real Gerard Blasco Josep Puig Maria Moreno Gemma Xifra Javier Sánchez‐Gonzalez Jose Maria Alustiza Salvador Pedraza Wifredo Ricart José María Moreno‐Navarrete 《Obesity (Silver Spring, Md.)》2016,24(2):352-358
Objective : Circulating and adipose tissue markers of iron overload are increased in subjects with obesity. The aim is to study iron signals in adipose tissue. Methods: Adipose tissue R2* values and hepatic iron concentration (HIC) were evaluated using magnetic resonance imaging (MRI) in 23 middle‐aged subjects with obesity and 20 subjects without obesity. Results: Subcutaneous (SAT) and visceral adipose tissue (VAT) R2* were increased in subjects with obesity (P = 0.004 and P = 0.008) and correlated significantly and positively with HIC in all subjects. Strikingly, most of the associations of liver iron with metabolic parameters were replicated with SAT and VAT R2*. BMI, waist circumference, fat mass, HOMA value, and C‐reactive protein positively correlated with HIC and SAT and VAT R2*. BMI or percent fat mass (but not insulin resistance) contributed independently to 26.8‐34.8% of the variance in sex‐ and age‐adjusted SAT or VAT R2* (β > 0.40, P < 0.005). Within subjects with obesity, total cholesterol independently contributed to 14.8% of sex‐ and age‐adjusted VAT iron variance (β = 0.50, P = 0.025). Conclusions: Increased R2* in adipose tissue, which might indicate iron content, runs in parallel to liver iron stores of subjects with obesity. VAT iron seems also associated with serum cholesterol within subjects with obesity. 相似文献
85.
Light-dependent degradation of nitrophenols by the phototrophic bacterium Rhodobacter capsulatus E1F1. 总被引:3,自引:2,他引:1 下载免费PDF全文
Rhodobacter capsulatus E1F1, a phototrophic purple nonsulfur bacterium capable of photoassimilating nitrate or nitrite, grew phototrophically in the presence of mono- and dinitrophenols with acetate as a carbon source, the highest growth levels being obtained under microaerobic conditions. Utilization of 2,4-dinitrophenol was strictly light dependent, was inhibited by O2 and by ammonium, and took place with the simultaneous and stoichiometric production of 2-amino-4-nitrophenol, which accumulated in the medium and was poorly used for further growth in anaerobiosis. Metabolism of mononitrophenols was also light dependent but was activated by O2 and by ammonium. Metabolism of nitrophenols seemed to depend on inducible systems which were repressed in nitrogen-starved cells. Induction of the in vivo 2,4-dinitrophenol reducing system was strongly inhibited by chloramphenicol. 相似文献
86.
F. J. Alvarez C. Cervantes R. Villalba I. Blasco R. Martínez-Murillo J. M. Polak Dr. JOsé Rodrigo 《Cell and tissue research》1988,254(2):429-437
Summary Calcitonin gene-related peptide (CGRP)-and vasoactive intestinal polypeptide (VIP)-immunoreactivity were observed to coexist in Merkel cells of cats. No differences in peptide content were found between Merkel cells located in epithelia of the hard palate, in hairy and glabrous skin of the upper lip, and in vibrissae follicles. CGRP-and VIP-immunoreactive nerve fibres were also found near CGRP/VIP-immunoreactive Merkel cells. In the vibrissae follicles some CGRP-and VIP-immunoreactive nerve terminals end abutting on the glassy membrane. Other CGRP immunoreactive nerve fibres penetrate the epithelium of the skin and end within it. Electron microscopy of vibrissae follicles revealed that Merkel cell neuntes are not immunostained and that immunostained nerve fibres form unmyelinated bundles before ending freely. Thus, CGRP-and VIP immunoreactive nerve fibres in cat skin do not end as Merkel cell neuntes but as different kinds of free nerve endings. 相似文献
87.
Plasma immunoreactive glucagon levels (IRG), plasma glucose levels and brain and liver glycogen concentrations were analyzed in carp (adapted to 15 degrees C) subjected to short-term temperature changes (1.6 or 11 h, at 5 degrees C or 28 degrees C, respectively) and to long-term temperature changes (21 months at 28 degrees C). The high temperature (28 degrees C) produced significant increases in IRG in both short and long-term experiments. Brain glycogen also decreased in both experiments whereas liver glycogen only changed in the long-term experiment. Low temperatures did not provoke any changes either in IRG or in liver glycogen, whereas brain glycogen decreased in the 1 h exposure. In short, under these conditions in carp, IRG did not respond to low temperature but could play an important role in high temperature acclimation. 相似文献
88.
89.
Cooperation between p53 mutation and high telomerase transgenic expression in spontaneous cancer development 下载免费PDF全文
Telomerase reintroduction in adult somatic tissues is envisioned as a way to extend their proliferative capacity. It is still a question, however, whether constitutive telomerase expression in adult tissues impacts the normal aging and spontaneous cancer incidence of an organism. Here, we studied the aging and spontaneous cancer incidence of mice with transgenic telomerase expression in a wide range of adult tissues, K5-Tert mice. For this, we maintained large colonies of K5-Tert mice for more than 2 years. K5-Tert mice showed a decreased life span compared to wild-type cohorts associated with a higher incidence of preneoplastic and neoplastic lesions in various tissue types. Neoplasias in K5-Tert mice were coincident with transgene expression in the affected tissues. These observations suggest that high telomerase activity may cooperate with genetic alterations that occur with age to promote tumorigenesis. Indeed, we demonstrate here that increased cancer incidence and the reduced viability of K5-Tert mice are aggravated in a p53(+/-) genetic background, indicating that telomerase cooperates with loss of p53 function in inducing tumorigenesis. Altogether, these results demonstrate that constitutive high levels of telomerase activity result in a decreased life span associated with an increased incidence of neoplasias as the organism ages. 相似文献
90.
Three contemporary lines were formed from the progeny of 50 French Large White sows. In the first line, gilts were selected for ovulation rate at puberty. In the second line, they were selected for prenatal survival of the first two parities, corrected for ovulation rate. The control constituted the third line. Ovulation rate at puberty was analyzed using an animal model with a batch effect. Prenatal survival was analyzed with a repeatability animal model that included batch and parity effects. Flat priors were used to represent vague previous knowledge about parity and batch effects. Additive and residual effects were represented assuming that they were a priori normally distributed. Variance components were assumed to follow either uniform or inverted chi-square distributions, a priori. The use of different priors did not affect the results substantially. Heritabilities for ovulation rate ranged from 0.32 to 0.39, and from 0.11 to 0.16 for prenatal survival, depending on the prior used. The mean of the marginal posterior distribution of response to four generations of selection ranged from 0.38 to 0.40 ova per generation, and from 1.1 to 1.3% of the mean survival rate for average survival per generation. 相似文献