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121.
The beneficial effects of antioxidant nutrients, as well as complex plant extracts, in cerebral ischemia/reperfusion brain injury are well known. Mediterranean diet, rich in olive products, is associated with lower incidence of cardiovascular disease, cancer, inflammation and stroke. In this study, the possible neuroprotective effect of standardized dry olive leaf extract (OLE) is investigated for the first time. Transient global cerebral ischemia in Mongolian gerbils was used to investigate the OLE effects on different parameters of oxidative stress and neuronal damage in hippocampus. The biochemical measurements took place at different time points (80 min, 2, 4 and 24 h) after reperfusion. The effects of applied OLE were compared with effects of quercetin, a known neuroprotective plant flavonoid. Pretreatment with OLE (100 mg/kg, per os) significantly inhibited production of superoxide and nitric oxide, decreased lipid peroxidation, and increased superoxide dismutase activity in all time points examined. Furthermore, OLE offered histological improvement as seen by decreasing neuronal damage in CA1 region of hippocampus. The effects of applied OLE were significantly higher than effects of quercetin (100 mg/kg, per os). Our results indicate that OLE exerts a potent neuroprotective activity against neuronal damage in hippocampus after transient global cerebral ischemia, which could be attributed to its antioxidative properties.  相似文献   
122.
Single molecule localization microscopy (SMLM), which can provide up to an order of magnitude improvement in spatial resolution over conventional fluorescence microscopy, has the potential to be a highly useful tool for quantitative biological experiments. It has already been used for this purpose in varied fields in biology, ranging from molecular biology to neuroscience. In this review article, we briefly review the applications of SMLM in quantitative biology, and also the challenges involved and some of the solutions that have been proposed. Due to its advantages in labeling specificity and the relatively low overcounting caused by photoblinking when photo-activable fluorescent proteins (PA-FPs) are used as labels, we focus specifically on Photo-Activated Localization Microscopy (PALM), even though the ideas presented might be applicable to SMLM in general. Also, we focus on the following three quantitative measurements: single molecule counting, analysis of protein spatial distribution heterogeneity and co-localization analysis.  相似文献   
123.
Production of indole-3-acetic acid (IAA), a key physiological feature of culturable, O2-tolerant bacteria associated with the freshwater macrophyte Juncus effusus L., was examined over a period of 2 years. Up to 74% of rhizobacteria identified and tested produced IAA. The number of indoleacetic acid producers decreased in winter. IAA was produced even when L-tryptophan, a precursor of IAA, was not added to the medium. Most of the IAA-producing strains were dominated by strains that were not identifiable to species level on the basis of API testing. Based on 16S rRNA gene sequencing and fatty acid analysis, it was found that IAA-producing rhizosphere bacteria associated with the freshwater wetland plant Juncus effusus L. are representatives of several families, including the Enterobacteriaceae, Pseudomonadaceae, Aeromonadaceae, Burkholderiaceae, and Bacillaceae. This study identifies numerous potentially important bacterial physiological groups of freshwater wetlands. Additionally, the study provides a baseline for monitoring and assessing the mutualistic relationships of wetland plants with rhizosphere bacteria in freshwater wetlands.  相似文献   
124.
Patients with biallelic truncating mutations in PALB2 have a severe form of Fanconi anaemia (FA-N), with a predisposition for developing embryonal-type tumours in infancy. Here we describe two unusual patients from a single family, carrying biallelic PALB2 mutations, one truncating, c.1676_1677delAAinsG;(p.Gln559ArgfsTer2), and the second, c.2586+1G>A; p.Thr839_Lys862del resulting in an in frame skip of exon 6 (24 amino acids). Strikingly, the affected individuals did not exhibit the severe developmental defects typical of FA-N patients and initially presented with B cell non-Hodgkin lymphoma. The expressed p.Thr839_Lys862del mutant PALB2 protein retained the ability to interact with BRCA2, previously unreported in FA-N patients. There was also a large increased chromosomal radiosensitivity following irradiation in G2 and increased sensitivity to mitomycin C. Although patient cells were unable to form Rad51 foci following exposure to either DNA damaging agent, U2OS cells, in which the mutant PALB2 with in frame skip of exon 6 was induced, did show recruitment of Rad51 to foci following damage. We conclude that a very mild form of FA-N exists arising from a hypomorphic PALB2 allele.  相似文献   
125.
Many citizens from the Osijek-Baranja County, in order to survive, left their homes during the 1991/92 war in Croatia and spent between 5 and 7 years in exile. The aim of this pilot research was to assess the health status (physical, mental and social) of refugee /returnee population and their use of health services, to identify the factors influencing their adaptation, and to propose the health programs, psychological and social support, which could help foster integration into the social and community life, education and employment. The study was done on a randomized sample of 589 respondents using the 2003 Croatian Health Survey with an additional questionnaire related to the problems of returnees. The results of the study show good organization of health service in returnees' communities, with exception of gynecological and dental services. There was also a presence of health transportation problem and the problem in the supply of medicines. Finally, the results show that the returnees' communities were dominated by social problems such as lack of employment, lack of support for elderly, poverty, and concerns for children's prospects. This implies the necessity for intervention in both mental and social aspects. Measures to be undertaken in the next stage of the Project will be aimed at the work in the refugee communities and based on public health working methods such as organization of the community by stimulating intergenerational solidarity, education and raising awareness of self-help.  相似文献   
126.
The aim of the study was to determine quantitative and qualitative differences in the morphological-motor status between elementary school first-graders of both sexes in 1992 and 2002. A standard set of 11 variables currently used in the Croatian school system to evaluate the morphological, motor and functional status of school children was employed at the beginning of academic years in a sample of 635 children (325 male and 310 female) in 1992 and a sample of 850 children (430 male and 420 female) in 2002. The mean age of study children was 7 years (+/- 2 months). Results of canonic discriminative analysis revealed the male children enrolled in elementary school first grade in 2002 to show better performance on the tests of aerobic endurance, static strength and explosive strength, and to have greater mass of muscle tissue and less adipose tissue, while achieving poorer results on the test of movement frequency than their 1992 counterparts. Female children tested in 2002 showed better results on the test of aerobic endurance and all tests of strength factors, with greater mass of muscle tissue and less adipose tissue, while yielding poorer results on the tests of flexibility, coordination and movement frequency as compared with their 1992 counterparts. Factor analysis in the morphological-motor system isolated three varimax factors each in children of both sexes tested in 1992 and 2002. First factor showed a pattern of a general morphological factor predominantly defined by body weight and volume in the children of both sexes from both study years. Second factor showed a pattern of a general motoricity factor predominantly defined by explosive strength, coordination and speed in children tested in 1992, whereas in their 2002 counterparts the general motoricity factor was predominantly defined by the factors of strength and endurance. Third factor was defined by flexibility in both 1992 and 2002 children. In female children tested in 1992, second factor mostly defined energy regulation with predominance of explosive and static strength, followed by coordination, whereas third factor was defined by movement frequency and aerobic endurance. In female children tested in 2002, second factor mostly defined energy regulation with predominance of explosive and repetitive strength, followed by aerobic endurance and coordination, whereas third factor was defined by movement frequency followed by muscle tone regulation.  相似文献   
127.
A simple ion-exchange HPLC-UV method was developed for determination of major allergens from mugwort pollen and kiwi fruit extracts in mass-units. The separation of Art v 1 and Act c 1 from other components in the extracts was achieved in one step. The extinction coefficients used in the study were theoretically determined and compared to the extinction coefficients determined by gravimetry. We also reported a close correlation of the major allergen contents with the overall allergenic potency of the extracts determined by inhibition ELISA. This method could be a useful tool for standardization of allergenic extracts for clinical use.  相似文献   
128.
129.
Here we present Cys-Ph-TAHA, a new nonadentate lanthanide tag for the paramagnetic labelling of proteins. The tag can be easily synthesized and is stereochemically homogenous over a wide range of temperatures, yielding NMR spectra with a single set of peaks. Bound to ubiquitin, it induced large residual dipolar couplings and pseudocontact shifts that could be measured easily and agreed very well with the protein structure. We show that Cys-Ph-TAHA can be used to label large proteins that are biochemically challenging such as the Lac repressor in a 90 kDa ternary complex with DNA and inducer.  相似文献   
130.
Thrombin-dependent platelet activation has been shown to be important in the setting of angioplasty and stenting, which may cause ischemic complications including acute myocardial infarction and death. Inhibitors of the high-affinity thrombin receptor, protease-activated receptor 1 (PAR1), are now being evaluated in clinical trials for safety and efficacy in patients with atherothrombotic disease. However, it is unknown whether chronic inhibition of PAR1 in these large patient populations will have beneficial or possibly adverse effects on other biologic processes involved in blood vessel homeostasis and the response to vascular injury. Most recently, PAR1 was found to be cleaved at a distinct site by matrix metalloprotease-1 (MMP-1) to create a longer tethered ligand, which activates a distinct spectrum of G protein pathways in platelets. The differential activation by serine proteases such as thrombin and the metalloprotease MMP-1, places the protease receptor PAR1 at the junction of two major protease classes critically involved in thrombosis, matrix remodeling, and the response to vascular injury.  相似文献   
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