排序方式: 共有144条查询结果,搜索用时 390 毫秒
71.
Erik Gabrielsson Hanna Ellis Sandra Feldt Haining Tian Gerrit Boschloo Anders Hagfeldt Licheng Sun 《Liver Transplantation》2013,3(12):1647-1656
A series of four new dyes, based on the D35 type donor moiety with varied linker units, is synthesized using a facile convergent/divergent method, enabled by an improved synthesis of the D35 donor. The dyes are evaluated in dye sensitized solar cells with Co(II/III)(bpy)3‐based electrolytes. By extending the linker fragment, higher photocurrents and solar energy conversion efficiencies are achieved. It is also found that the linker unit plays a crucial role in maintaining a high open‐circuit photovoltage. Based on the photovoltaic performance it is concluded that the hexylthiophene unit is the most suitable for this purpose, as it allows further enhancement of the already high open‐circuit voltage of D35 to 0.92 V. The best dye in this series reaches an efficiency of 6.8%. 相似文献
72.
Erick R. G. Claudio Patrick W. Endlich Roger L. Santos Margareth R. Moysés Nazaré S. Bissoli S?nia A. Gouvêa Josiane F. Silva Virginia S. Lemos Glaucia R. Abreu 《PloS one》2013,8(6)
The aim of this study was to evaluate the effects of swimming training (SW) and oestrogen replacement therapy (ERT) on coronary vascular reactivity and the expression of antioxidant enzymes in ovariectomized rats. Animals were randomly assigned to one of five groups: sham (SH), ovariectomized (OVX), ovariectomized with E2 (OE2), ovariectomized with exercise (OSW), and ovariectomized with E2 plus exercise (OE2+SW). The SW protocol (5×/week, 60 min/day) and/or ERT were conducted for 8 weeks; the vasodilator response to bradykinin was analysed (Langendorff Method), and the expression of antioxidant enzymes (SOD-1 and 2, catalase) and eNOS and iNOS were evaluated by Western blotting. SW and ERT improved the vasodilator response to the highest dose of bradykinin (1000 ng). However, in the OSW group, this response was improved at 100, 300 and 1000 ng when compared to OVX (p<0,05). The SOD-1 expression was increased in all treated/trained groups compared to the OVX group (p<0,05), and catalase expression increased in the OSW group only. In the trained group, eNOS increased vs. OE2, and iNOS decreased vs. SHAM (p<0,05). SW may represent an alternative to ERT by improving coronary vasodilation, most likely by increasing antioxidant enzyme and eNOS expression and augmenting NO bioavailability. 相似文献
73.
Vildete A. S. Carmo Mônica C. De Oliveira Eduardo C. O. Reis Tânia M. P. D. Guimarães José M. C. Vilela Margareth S. Andrade 《Journal of liposome research》2013,23(1):59-70
Complement activation is an important step in the acceleration of liposome clearance. The anaphylatoxins released following complement activation may motivate a wide variety of physiologic changes. We performed physicochemical characterization and in vitro studies of the interaction of complement system with both noncirculating and long-circulating pH-sensitive and nonpH-sensitive liposomes. The liposomes were characterized by diameter, zeta potential, and atomic force microscopy (AFM). The study of liposome interactions with complement system was conducted using hemolytic assay in rat serum. All liposomes presented a similar mean diameter (between 99.8 and 124.3 nm). The zeta potential was negative in all liposome preparations, except in liposomes modified with aminopoly (ethyleneglycol) 2000-distearoylphosphatidylethanolamine (aPEG2000-DSPE), which presented positive zeta potential. Atomic force microscopy images showed that non–long-circulating pH-sensitive liposomes are prone to vesicles aggregation. Non–pH-sensitive liposomes complement system activates, while pH-sensitive liposomes showed to be poor complement activators in rat serum. 相似文献
74.
75.
76.
Danilo O. Carvalho Derric Nimmo Neil Naish Andrew R. McKemey Pam Gray André B. B. Wilke Mauro T. Marrelli Jair F. Virginio Luke Alphey Margareth L. Capurro 《Journal of visualized experiments : JoVE》2014,(83)
New techniques and methods are being sought to try to win the battle against mosquitoes. Recent advances in molecular techniques have led to the development of new and innovative methods of mosquito control based around the Sterile Insect Technique (SIT)1-3. A control method known as RIDL (Release of Insects carrying a Dominant Lethal)4, is based around SIT, but uses genetic methods to remove the need for radiation-sterilization5-8. A RIDL strain of Ae. aegypti was successfully tested in the field in Grand Cayman9,10; further field use is planned or in progress in other countries around the world.Mass rearing of insects has been established in several insect species and to levels of billions a week. However, in mosquitoes, rearing has generally been performed on a much smaller scale, with most large scale rearing being performed in the 1970s and 80s. For a RIDL program it is desirable to release as few females as possible as they bite and transmit disease. In a mass rearing program there are several stages to produce the males to be released: egg production, rearing eggs until pupation, and then sorting males from females before release. These males are then used for a RIDL control program, released as either pupae or adults11,12.To suppress a mosquito population using RIDL a large number of high quality male adults need to be reared13,14. The following describes the methods for the mass rearing of OX513A, a RIDL strain of Ae. aegypti 8, for release and covers the techniques required for the production of eggs and mass rearing RIDL males for a control program. 相似文献
77.
Debora Monteiro Moretti Lalima Gagan Ahuja Rodrigo Dutra Nunes Cecília Oliveira Cudischevitch Carlos Renato Oliveira Daumas-Filho Priscilla Medeiros-Castro Guilherme Ventura-Martins Willy Jablonka Felipe Gazos-Lopes Raquel Senna Marcos Henrique Ferreira Sorgine Klaus Hartfelder Margareth Capurro Georgia Correa Atella Rafael Dias Mesquita Mário Alberto Cardoso Silva-Neto 《PloS one》2014,9(8)
Background
Protein Tyrosine Phosphatases (PTPs) are enzymes that catalyze phosphotyrosine dephosphorylation and modulate cell differentiation, growth and metabolism. In mammals, PTPs play a key role in the modulation of canonical pathways involved in metabolism and immunity. PTP1B is the prototype member of classical PTPs and a major target for treating human diseases, such as cancer, obesity and diabetes. These signaling enzymes are, hence, targets of a wide array of inhibitors. Anautogenous mosquitoes rely on blood meals to lay eggs and are vectors of the most prevalent human diseases. Identifying the mosquito ortholog of PTP1B and determining its involvement in egg production is, therefore, important in the search for a novel and crucial target for vector control.Methodology/Principal Findings
We conducted an analysis to identify the ortholog of mammalian PTP1B in the Aedes aegypti genome. We identified eight genes coding for classical PTPs. In silico structural and functional analyses of proteins coded by such genes revealed that four of these code for catalytically active enzymes. Among the four genes coding for active PTPs, AAEL001919 exhibits the greatest degree of homology with the mammalian PTP1B. Next, we evaluated the role of this enzyme in egg formation. Blood feeding largely affects AAEL001919 expression, especially in the fat body and ovaries. These tissues are critically involved in the synthesis and storage of vitellogenin, the major yolk protein. Including the classical PTP inhibitor sodium orthovanadate or the PTP substrate DiFMUP in the blood meal decreased vitellogenin synthesis and egg production. Similarly, silencing AAEL001919 using RNA interference (RNAi) assays resulted in 30% suppression of egg production.Conclusions/Significance
The data reported herein implicate, for the first time, a gene that codes for a classical PTP in mosquito egg formation. These findings raise the possibility that this class of enzymes may be used as novel targets to block egg formation in mosquitoes. 相似文献78.
Lina ?kesson Johan Trygg Jessica M. Fuller Rasmus Madsen Jon Gabrielsson Stephen Bruce Hans Stenlund Terry Tupling Ranae Pefley Torbj?rn Lundstedt ?ke Lernmark Thomas Moritz 《Metabolomics : Official journal of the Metabolomic Society》2011,7(4):593-603
The clinical presentation of type 1 diabetes is preceded by a prodrome of beta cell autoimmunity. We probed the short period of subtle metabolic abnormalities, which precede the acute onset of diabetes in the spontaneously diabetic BB rat, by analyzing the serum metabolite profile detected with combined gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/mass spectrometry (LC/MS). We found that the metabolite pattern prior to diabetes included 17 metabolites, which differed between individual diabetes prone (DP) BB rats and their age and sex matched diabetes resistant (DR) littermates. As the metabolite signature at the 40?days of age baseline failed to distinguish DP from DR, there was a brief 10-day period after which the diabetes prediction pattern was observed, that includes fatty acids (e.g. oleamide), phospholipids (e.g. phosphocholines) and amino acids (e.g. isoleucine). It is concluded that distinct changes in the serum metabolite pattern predict type 1 diabetes and precede the appearance of insulitis in spontaneously diabetic BB DP rats. This observation should prove useful to dissect mechanisms of type 1 diabetes. 相似文献
79.
80.
Fabian Grammes Felipe Eduardo Reveco Odd Helge Romarheim Thor Landsverk Liv Torunn Mydland Margareth ?verland 《PloS one》2013,8(12)
Intestinal inflammation, caused by impaired intestinal homeostasis, is a serious condition in both animals and humans. The use of conventional extracted soybean meal (SBM) in diets for Atlantic salmon and several other fish species is known to induce enteropathy in the distal intestine, a condition often referred to as SBM induced enteropathy (SBMIE). In the present study, we investigated the potential of different microbial ingredients to alleviate SBMIE in Atlantic salmon, as a model of feed-induced inflammation. The dietary treatments consisted of a negative control based on fish meal (FM), a positive control based on 20% SBM, and four experimental diets combining 20% SBM with either one of the three yeasts Candida utilis (CU), Kluyveromyces marxianus (KM), Saccharomyces cerevisiae (SC) or the microalgae Chlorella vulgaris (CV). Histopathological examination of the distal intestine showed that all fish fed the SC or SBM diets developed characteristic signs of SBMIE, while those fed the FM, CV or CU diets showed a healthy intestine. Fish fed the KM diet showed intermediate signs of SBMIE. Corroborating results were obtained when measuring the relative length of PCNA positive cells in the crypts of the distal intestine. Gene set enrichment analysis revealed decreased expression of amino acid, fat and drug metabolism pathways as well as increased expression of the pathways for NOD-like receptor signalling and chemokine signalling in both the SC and SBM groups while CV and CU were similar to FM and KM was intermediate. Gene expression of antimicrobial peptides was reduced in the groups showing SBMIE. The characterisation of microbial communities using PCR-DGGE showed a relative increased abundance of Firmicutes bacteria in fish fed the SC or SBM diets. Overall, our results show that both CU and CV were highly effective to counteract SBMIE, while KM had less effect and SC had no functional effects. 相似文献