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91.

Background

Albumin constitutes the most abundant circulating antioxidant and prevents oxidative damages. However, in diabetes, this plasmatic protein is exposed to several oxidative modifications, which impact on albumin antioxidant properties.

Methods

Most studies dealing on albumin antioxidant activities were conducted on in vitro modified protein. Here we tried to decipher whether reduced antioxidant properties of albumin could be evidenced in vivo. For this, we compared the antioxidant properties of albumin purified from diabetic patients to in vitro models of glycated albumin.

Results

Both in vivo and in vitro glycated albumins displayed impaired antioxidant activities in the free radical-induced hemolysis test. Surprisingly, the ORAC method (Oxygen Radical Antioxidant Capacity) showed an enhanced antioxidant activity for glycated albumin. Faced with this paradox, we investigated antioxidant and anti-inflammatory activities of our albumin preparations on cultured cells (macrophages and adipocytes). Reduced cellular metabolism and enhanced intracellular oxidative stress were measured in cells treated with albumin from diabetics. NF-kB –mediated gene induction was higher in macrophages treated with both type of glycated albumin compared with cells treated with native albumin. Anti inflammatory activity of native albumin is significantly impaired after in vitro glycation and albumin purified from diabetics significantly enhanced IL6 secretion by adipocytes. Expression of receptor for advanced glycation products is significantly enhanced in glycated albumin-treated cells.

Conclusions and general significance

Our results bring new evidences on the deleterious impairments of albumin important functions after glycation and emphasize the importance of in vivo model of glycation in studies relied to diabetes pathology.  相似文献   
92.
This work was based on field screening procedure to detect the population density of Aphis craccivora for two successive seasons (2004–2005) and (2005–2006) to emphasis the relation between the economic injury level (EIL) and yield loss.

Results obtained showed that the equilibrium position (steady point) during the first and second season was 9.06 and 3.32 individuals/five leaflets, respectively, while the injury level was 3.4 and 1.16 individuals/leaflets. When the bean plant was subjected to three successive insecticidal applications during the early growing, season is sufficient to decrease the yield loss significantly (yield capacity 21.43 Ard./fed.) with comparing to untreated plant (14.98 Ard./fed.), while the plants exposure for one treatment was 17.36 Ard./fed. The EIL was 8.6 individual of aphids/plant depending on the market price of bean and control cost during the season.  相似文献   
93.
Abiotic factors in the introduced area can limit the establishment of exotic species. Adaptation to new abiotic parameters through plastic responses is important for their establishment and distribution pattern. Survival and growth of exotic hydrophytes are related to their plasticity and their ability to adapt to local conditions. Light and water depth are two of the predominant factors determining survival, growth, distribution and abundance of aquatic plants. Although many studies have been carried out on the effect of water level and light on plant performance, their potential interactions are poorly understood. Here, we carried out an outdoor mesocosm experiment, in order to test the role of water depth, light intensity and their potential interactions on the growth and vigour of the invasive macrophyte species Ludwigia grandiflora. Three light intensities (100%, 70% and 50% of sunlight) and three water depths (30, 50 and 80 cm) were tested over a 6-week period, in spring, summer and autumn 2011. We showed that the mortality, biomass, apical and lateral growth of L. grandiflora, as well as its biomass allocation, varied according to the season and responded to both light intensity and water depth. Interactions between water depth and light intensity can have an amplifying effect on the growth of L. grandiflora. Similarities between shade and deep water adaptation responses were observed. A higher biomass and a high morphological plasticity in response to these factors were found particularly at the beginning of the life cycle. Although the invasive amphibious L. grandiflora shows a high tolerance to different water levels and light intensities, the optimal growth conditions for L. grandiflora in our experiment seem to be under full sunlight and in 30 cm of water. Colonization of light or low shade aquatic habitats, as well as shallow environments, can occur due to the high plasticity of L. grandiflora. These results may be important relative to increasing level of water bodies under climatic changes.  相似文献   
94.
Importance to know and understand diversity of Himalayan plants is increasingly recognized considering the fact that various natural and anthropogenic pressures might bring about serious influences to morphological and genetic diversity of the vegetation in the region. In this context, Valeriana jatamansi was investigated in detail, taking into account its importance in various Ayurvedic and modern medicines. Randomly selected mature plants from twenty five different populations (located between 1215 m to 2775 m asl) of V. jatamansi were analysed for their morphological attributes. Further, ISSR markers were used to detect genetic variation among 151 plants of selected 25 populations. Use of 20 primers yielded 125 reproducible polymorphic loci which were used to estimate different parameters of genetic diversity. These parameters were in turn applied to develop relationships with habitat types and altitude range. Significant variation (p < 0.05) in above ground dry weight (AGDW) and below ground dry weight (BGDW) across the populations was observed. Nei's genetic diversity index (He) ranged from 0.25 to 0.37 across the populations, with a mean of 0.31. Genetic diversity exhibited a decreasing trend with increasing altitude, and maximum diversity (He = 0.325) was observed in the range of 1201–1500 m asl. Among the different habitat conditions, highest genetic diversity (He = 0.334; Pp = 84.38) was observed in grassland habitats while minimum in mixed forest habitats (He = 0.285; Pp = 72.433). The genetic diversity (He) had significant negative relationships with AGDW, BGDW and rhizome diameter (Pearson r = −0.359, −0.424 and −0.317, respectively; p < 0.05). The genetic characterization of V. jatamansi from the western Himalaya by this study suggests influences of habitat types and the altitudinal range upon genetic diversity, and based on these proposals for conservation strategies in favour of the species are made.  相似文献   
95.
Twelve groups of fossils, including graptolites, brachiopods, nautiloids, trilobites, corals, crinoids, bryozoans, conodonts, ostracods, gastropods, chitinozoans, and acritarchs expired in different but substantial magnitude and global extent during the late Caradoc to latest Ashgill. It indicates a multiple‐episodic mass extinction containing the possible Prologue (late Caradoc), Climax episode (Rawtheyan) and Epilogue (late Hirnantian). The main causes of this mass extinction are recognized as a global sea‐level lowering in the climax and remarkable rapid rise at the final, and global cooling. The Chinese data, especially from the South China Paleoplate, are evaluated first. They are significant for explaining this global bioevent.  相似文献   
96.
Eduardo Kohn 《Anthrozo?s》2013,26(2):203-206
ABSTRACT

Although the occurrence of cat-caretaking of free-roaming cats is widespread, particularly so in countries with a climate suitable for cats to reproduce year-round, our knowledge of this relationship is still incomplete. People who engage in daily activities of feeding and caring for groups of free-roaming cats (cat caretakers) are known to be devoted to their cats and invest considerable resources in their care, including neutering and veterinary care. These caretakers often encounter difficulties, such as resentment by neighbors and lack of cooperation or financing by the municipal veterinary services. Despite the fundamental understanding of these caretakers' high daily commitment, and sometimes strong bond with the cats, detailed knowledge is still lacking regarding the nature of this bond, the difficulties that ensue from this daily occupation, and the relationship between the two. The purpose of this study was thus to acquire a deeper understanding, by means of an in-depth interview with cat caretakers. The study has identified, for the first time, two distinct emotional approaches that accompany extensive caretaking for free-roaming cats: emotional attachment and emotional detachment. We show how these two different responses affect both social and financial aspects in the caretakers' lives, and report on the ways in which these individuals experience cat caretaking. Our findings provide a first systematic understanding of the relationship between the level of technical caretaking (feeding, medical care, etc.) and the level of emotional involvement, and reveal the ambivalence often inherent in human–animal relations in general and the caretaker–cat bond in particular. The understanding acquired here can be put into practice to reduce the emotional and technical difficulties experienced by cat caretakers, as well as to improve free-roaming cat management efforts and cat welfare. By increasing public and municipal awareness of the possible contribution of cat caretakers to cat management, and of the emotional and technical difficulties they experience, both the caretakers and other community members can benefit.  相似文献   
97.
二斑叶螨抗螺螨酯品系GST基因的克隆与表达分析   总被引:1,自引:0,他引:1  
【目的】揭示二斑叶螨Tetranychus urticae对螺螨酯的分子抗性机理。【方法】利用RT-PCR克隆了二斑叶螨的谷胱甘肽-S-转移酶(glutathione S-transferase, GST)基因 cDNA 全长序列, 采用生物信息学软件分析了克隆基因的编码蛋白特性; 利用实时荧光定量PCR 方法分析GST基因在二斑叶螨的螺螨酯抗性与敏感品系中的表达差异。【结果】克隆获得的谷胱甘肽-S-转移酶2个基因分别被命名为TuGSTd1和TuGSTd2 (GenBank登录号分别为: KC445659和KC445660)。序列分析发现, TuGSTd1的开放阅读框长度为648 bp, 编码215个氨基酸, 分子量约为24.47 kDa, 理论等电点为5.49; TuGSTd2的开放阅读框为648 bp, 编码215个氨基酸, 分子量约为24.57 kDa, 理论等电点为6.33。系统发育分析表明这两个基因与桔全爪螨Panonychus citri Delta家族的GST基因的氨基酸序列一致性为93%。实时荧光定量PCR 结果表明, TuGSTd1和TuGSTd2在二斑叶螨抗螺螨酯品系中的相对表达量分别为敏感品系的5.60和3.75 倍。【结论】 GST基因在二斑叶螨抗螺螨酯品系中的相对表达量均显著高于敏感品系, 据此推测GST基因的过量表达可能与其对螺螨酯的抗性形成有关。  相似文献   
98.
Phototherapy can be used in two completely different but complementary therapeutic applications. While low level laser (or light) therapy (LLLT) uses red or near-infrared light alone to reduce inflammation, pain and stimulate tissue repair and regeneration, photodynamic therapy (PDT) uses the combination of light plus non-toxic dyes (called photosensitizers) to produce reactive oxygen species that can kill infectious microorganisms and cancer cells or destroy unwanted tissue (neo-vascularization in the choroid, atherosclerotic plaques in the arteries). The recent development of nanotechnology applied to medicine (nanomedicine) has opened a new front of advancement in the field of phototherapy and has provided hope for the development of nanoscale drug delivery platforms for effective killing of pathological cells and to promote repair and regeneration. Despite the well-known beneficial effects of phototherapy and nanomaterials in producing the killing of unwanted cells and promoting repair and regeneration, there are few reports that combine all three elements i.e. phototherapy, nanotechnology and, tissue repair and regeneration. However, these areas in all possible binary combinations have been addressed by many workers. The present review aims at highlighting the combined multi-model applications of phototherapy, nanotechnology and, reparative and regeneration medicine and outlines current strategies, future applications and limitations of nanoscale-assisted phototherapy for the management of cancers, microbial infections and other diseases, and to promote tissue repair and regeneration.  相似文献   
99.
1. Despite non‐point‐source (NPS) pollution being perhaps the most ubiquitous stressor affecting urban streams, there is a lack of research assessing how urban NPS pollution affects stream ecosystems. We used a natural experimental design approach to assess how stream macroinvertebrate community structure, secondary production and trophic structure are influenced by urban NPS pollution in six streams. 2. Differences in macroinvertebrate community structure and secondary production among sites were highly correlated with stream‐water specific conductivity and dissolved inorganic phosphorus (DIP) concentrations. Macroinvertebrate richness, the Shannon diversity index and the Shannon evenness index were all negatively correlated with specific conductivity. These patterns were driven by differences in the richness and production of EPT and other intolerant taxa. Production of the five most productive taxa, tolerant taxa, non‐insect taxa and primary consumers were all positively correlated with stream‐water DIP. 3. Despite the positive correlation between primary consumer production and DIP, there was no correlation between macroinvertebrate predator production and either total or primary consumer macroinvertebrate production. This was observed because DIP was positively correlated with the production of non‐insect macroinvertebrate taxa assumed to be relatively unavailable for macroinvertebrate predator consumption. After removing production of these taxa, we observed a strong positive correlation between macroinvertebrate predator production and production of available prey. 4. Our results suggest that urban NPS pollution not only affects macroinvertebrate community structure, but also alters secondary production and trophic‐level dynamics. Differences in taxon production in our study indicate the potential for altered energy flow through stream food webs and potential effects on subsidies of aquatic insect prey to riparian food webs.  相似文献   
100.
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