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991.
Meat is an important source of animal protein but, at the same time, it includes saturated fatty acids, which makes it a potential cause of different cardiovascular diseases and still little is known about influence of age and sex on these parameters in roe deer muscles. The aim of this study was to determine the effect of age and sex on the CLA and other fatty acids content in the musculus longissimus lumborum in 67 roe deer (Capreolus capreolus L.). In the meat from the oldest individuals a higher content of CLA was noted (89.76 [mg/kg]) when compared to the fawns (42 [mg/kg]). In this research meat from roe deer does showed in general a higher percentage proportion of SFAs and MUFAs, but lower of PUFAs, than the meat from bucks. These results may provide an important source of information for consumers of roe deer meat because of differences between CLA and other fatty acids content depending on age and sex of the animals. Meat from roebucks is the most advantageous for dietary purposes. 相似文献
992.
The aim of this work was to compare the concentrations of calcium and phosphorus and Ca/P ratio in the meat of females and males of the roach (Rutilus rutilus L.) caught from the Brda River. The study involved 40 roach individuals caught in fall and spring (10 females and 10 males from each season). The muscle samples for analyses were taken from the large side muscle of the fish body above the lateral line. Ca concentrations were determined by atomic absorption spectrophotometry; P content was analyzed by the colorimetric method. Calcium concentration in the meat of analysed roach was higher in samples collected from fish caught in spring and equaled 1.82 g kg(-1) in females and 1.93 g kg(-1) in males. Values for individuals from autumn amounted to 0.83 and 1.10 g kg(-1), respectively. Statistically significant differences in calcium content were detected between individuals caught in different seasons, but samples taken from females and males caught within one season did not differ substantially. The mean value of P in the meat of analysed roach caught in spring was higher than in fish from autumn, and it was respectively 2.24 g kg(-1) in females and 2.30 g kg(-1) in males from spring, and 1.89 g kg(-1) in the tissue of females and 2.01 g kg(-1) in males in fish from autumn. The ratio of calcium to phosphorus in the meat of analysed wild roach ranged from 0.43:1 to 0.82:1. A negative and statistically significant correlation between Ca and P concentrations was found in the meat and the body length of analysed roach from the Brda River. 相似文献
993.
A microscopy-based endospore viability assay (micro-EVA) capable of enumerating germinable Clostridium endospores (GCEs) in less than 30 min has been validated and employed to determine GCE concentrations in Greenland ices and Atacama Desert soils. Inoculation onto agarose doped with Tb(3+) and d-alanine triggers Clostridium spore germination and the concomitant release of ~10(8) molecules of dipicolinic acid (DPA) per endospore, which, under pulsed UV excitation, enables enumeration of resultant green Tb(3+)-DPA luminescent spots as GCEs with time-gated luminescence microscopy. The intensity time courses of the luminescent spots were characteristic of stage I Clostridium spore germination dynamics. Micro-EVA was validated against traditional CFU cultivation from 0 to 1,000 total endospores/ml (i.e., phase-bright bodies/ml), yielding 56.4% ± 1.5% GCEs and 43.0% ± 1.0% CFU. We also show that d-alanine serves as a Clostridium-specific germinant (three species tested) that inhibits Bacillus germination of spores (five species tested) in that endospore concentration regime. Finally, GCE concentrations in Greenland ice cores and Atacama Desert soils were determined with micro-EVA, yielding 1 to 2 GCEs/ml of Greenland ice (versus <1 CFU/ml after 6 months of incubation) and 66 to 157 GCEs/g of Atacama Desert soil (versus 40 CFU/g soil). 相似文献
994.
995.
Dietrich-Muszalska A Olas B Kontek B Rabe-Jabłońska J 《International journal of biological macromolecules》2011,49(1):113-116
Since oxidative stress observed in schizophrenia may be caused partially by the treatment of patients with various antipsychotics, the aim of the study was to establish the effects of beta-d-glucan, polysaccharide derived from the yeast cell walls of species such as Saccharomyces cerevisiae, and the antipsychotics (the first generation antipsychotic (FGA) - haloperidol and the second generation antipsychotic (SGA) - amisulpride) action on plasma lipid peroxidation in vitro. Lipid peroxidation in human plasma was measured by the level of thiobarbituric acid reactive species (TBARS). The samples of plasma from healthy subjects were incubated with haloperidol or amisulpride in the presence of beta-glucan (4 μg/ml). The action of beta-d-glucan was also compared with the properties of a well characterized commercial monomeric polyphenol - resveratrol (3,4′,5-trihydroxystilbene, the final concentration - 4 μg/ml). The two-way analysis variance showed that the differences in TBARS levels were depended on the type of tested drugs (p = 7.9 × 10−6). We observed a statistically increase of the level of biomarker of lipid peroxidation such as TBARS after 1 and 24 h incubation of plasma with haloperidol compared to the control samples (p < 0.01, p < 0.02, respectively). Amisulpride, contrary to haloperidol (after 1 and 24 h) did not cause plasma lipid peroxidation (p > 0.05). We showed that in the presence of beta-glucan, lipid peroxidation in plasma samples treated with haloperidol was significantly decreased. Moreover, we did not observe the synergistic action of beta-glucan and amisulpride on the inhibition of plasma lipid peroxidation. However, the beta-d-glucan was found to be more effective antioxidant, than the solution of pure resveratrol. The presented results indicate that beta-glucan seems to have distinctly protective effects against the impairment of plasma lipid molecules induced by haloperidol. 相似文献
996.
Iorga B Neacsu CD Neiss WF Wagener R Paulsson M Stehle R Pfitzer G 《The Journal of general physiology》2011,137(3):255-270
The zebrafish is a potentially important and cost-effective model for studies of development, motility, regeneration, and inherited human diseases. The object of our work was to show whether myofibrils isolated from zebrafish striated muscle represent a valid subcellular contractile model. These organelles, which determine contractile function in muscle, were used in a fast kinetic mechanical technique based on an atomic force probe and video microscopy. Mechanical variables measured included rate constants of force development (k(ACT)) after Ca(2+) activation and of force decay (τ(REL)(-1)) during relaxation upon Ca(2+) removal, isometric force at maximal (F(max)) or partial Ca(2+) activations, and force response to an external stretch applied to the relaxed myofibril (F(pass)). Myotomal myofibrils from larvae developed greater active and passive forces, and contracted and relaxed faster than skeletal myofibrils from adult zebrafish, indicating developmental changes in the contractile organelles of the myotomal muscles. Compared with murine cardiac myofibrils, measurements of adult zebrafish ventricular myofibrils show that k(ACT), F(max), Ca(2+) sensitivity of the force, and F(pass) were comparable and τ(REL)(-1) was smaller. These results suggest that cardiac myofibrils from zebrafish, like those from mice, are suitable contractile models to study cardiac function at the sarcomeric level. The results prove the practicability and usefulness of mechanical and kinetic investigations on myofibrils isolated from larval and adult zebrafish muscles. This novel approach for investigating myotomal and myocardial function in zebrafish at the subcellular level, combined with the powerful genetic manipulations that are possible in the zebrafish, will allow the investigation of the functional primary consequences of human disease-related mutations in sarcomeric proteins in the zebrafish model. 相似文献
997.
Lobito AA Ramani SR Tom I Bazan JF Luis E Fairbrother WJ Ouyang W Gonzalez LC 《The Journal of biological chemistry》2011,286(21):18969-18981
998.
999.
Endocrine glands are well vascularised and the structure of their vessels facilitates the exchange of various substances, including hormones. These glands are a frequent experimental model in research on VEGF and angiogenesis. VEGF participates in the pathogenesis of diabetes. Diabetic nephropathy is in essence a microvascular disease that develops as a result of a confluence of haemodynamic and metabolic perturbations. Diabetic retinopathy is the commonest microvascular complication of diabetes mellitus and is the leading cause of blindness. In diabetic retinopathy, ischaemic states, and hence tissue hypoxia and angiogenesis, take place. The participation of angiogenesis and VEGF in the pathogenesis of neoplastic disease has been described in many papers. VEGF protein and mRNA have been found in cancers of the thyroid, bronchus, lungs, oesophagus, stomach, colon, liver, breast, ovary, uterus, kidney, and urinary bladder, and in malignant tumours of the brain and bone. There have been many reports of the connections between the degree of VEGF expression and tumour aggression and prognosis in patients. Richly vascularised are GEP NET. In neuroendocrine tumours, strong expression of VEGF, Flt-1 and KDR in relation to the unchanged surrounding tissues has been demonstrated. Depending on the disease entity or the degree of its severity, attempts to apply angiogenic and antiangiogenic therapy have being made. Antiangiogenic therapy (usually regarded as a form of cancer therapy) is based on: 1. inhibitory effects of proangiogenic ligands and their receptors; 2. stimulation or delivery of angiogenesis inhibitors; and 3. direct destruction of neoplastic tumour vasculature. 相似文献
1000.
Medicinal chemistry principles are being increasingly applied to the design of smaller, high purity, information-rich libraries. Recent computational advances in statistical methodology, the design of libraries to reduce ADMET problems, targeting protein families and revisiting natural products as sources of inspiration for scaffolds and reagents are all areas of progressive research. 相似文献