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161.
162.
Sara Baratchi Khashayar Khoshmanesh Catarina Sacristán David Depoil Donald Wlodkowic Peter McIntyre Arnan Mitchell 《Biotechnology advances》2014
Microfluidics has facilitated immunological studies by enhancing speed, efficiency and sensitivity of current analysis methods. It offers miniaturization of current laboratory equipment, and enables analysis of clinical samples without the need for sophisticated infrastructure. More importantly, microfluidics offers unique capabilities; including conducting multiple serial or parallel tasks as well as providing complex and precisely controlled environmental conditions that are not achievable using conventional laboratory equipment. Microfluidics is a promising technology for fundamental and applied immunological studies, allowing generation of high throughput, robust and portable platforms, opening a new area of automation in immunology. 相似文献
163.
Michele Santa Catarina Brodt Franchesco Della-Flora Nilton Cáceres 《Acta ethologica》2014,17(3):181-185
Blue Manakin Chiroxiphia caudata (Pipridae) has a lek mating system in which males cooperate in teams of two or more individuals for courtship displays to females. Males ascend through a dominance hierarchy to assume the rank of alpha male. Only alpha males copulate with females. In this study, we describe the ascension of a male to the alpha rank following the disappearance of the previous alpha male. The study was conducted in the seasonal Atlantic Forest of Southern Brazil. We observed nine banded males at two adjacent leks. The gamma male at the more successful lek also acted as an alpha male at a less successful lek 314 m away. Upon the disappearance of the alpha male at the more successful lek, the gamma gave up his alpha rank at the less successful lek and ascended to the alpha rank at the more successful lek, bypassing the beta male. Although a previous study suggests a strictly linear dominance hierarchy in C. caudata, with beta male ascending to alpha status, our results suggest that the rising to become the alpha male may be a more flexible and dynamic process than previously reported. 相似文献
164.
Luísa Custódio Fernando Soares Hugo Pereira Luísa Barreira Catarina Vizetto-Duarte Maria João Rodrigues Amélia Pilar Rauter Fernando Alberício João Varela 《Journal of applied phycology》2014,26(1):151-161
Organic and water extracts of Isochrysis galbana T-ISO (=Tisochrysis lutea), Tetraselmis sp. and Scenedesmus sp. were evaluated for their antioxidant activity, acetylcholinesterase (AChE) inhibition, cytotoxicity against tumour cell lines, and fatty acids and total phenolic content (TPC). I. galbana T-ISO had the highest TPC (3.18 mg GAE g?1) and radical scavenging activity, with an IC50 value of 1.9 mg mL?1 on the acetone extract. The extracts exhibited a higher ability to chelate Fe2+ than Cu2+, and the maximum Fe2+ chelating capacity was observed in the hexane extract of Scenedesmus sp. (IC50=0.73 mg mL?1) and Scenedesmus sp. (IC50?=?0.73 mg mL?1). The highest ability to inhibit AChE was observed in the water and ether extracts of Scenedesmus sp., with IC50 values of 0.11 and 0.15 mg mL?1, respectively, and in the water extract of I. galbana (IC50?=?0.16 mg mL?1). The acetone extract of I. galbana T-ISO significantly reduced the viability of human hepatic carcinoma HepG2 cells (IC50?=?81.3 μg mL?1) as compared to the non-tumour murine stromal S17 cell line, and displayed a selectivity index of 3.1 at the highest concentration tested (125 μg mL?1). All species presented a highly unsaturated fatty acids profile. Results suggest that these microalgae, particularly I. galbana T-ISO, could be a source of biomolecules for the pharmaceutical industry and the production of functional food ingredients and can be considered as an advantageous alternative to several currently produced microalgae. 相似文献
165.
Rita de Cássia Andrade Melo Emmily Margate Rodrigues de Barros Noel Guedes Loureiro Heloísa Ramos Lacerda de Melo Maria Amélia Vieira Maciel Ana Catarina Souza Lopes 《Current microbiology》2014,69(6):824-831
Klebsiella pneumoniae strains can produce different virulence factors, such as fimbrial adhesins and siderophores, which are important in the colonization and development of the infection. The aims of this study were to determine the occurrence of fimH, mrkD, and irp2 virulence genes in 22 KPC-2-producing K. pneumoniae isolates as well as 22 not producing-KPC isolates, from patients from different hospitals in Recife-PE, Brazil, and also to analyze the clonal relationship of the isolates by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). The genes were detected by PCR and DNA sequencing. The bla KPC-2 gene was identified in 22 KPC-positive isolates. On analyzing the antimicrobial susceptibility profile of the isolates, it was detected that polymyxin and amikacin were the antimicrobials of best activity against K. pneumoniae. On the other hand, five isolates exhibited resistance to polymyxin. In the KPC-positive group, was observed a high rate of resistance to cephalosporins, followed by carbapenems. Molecular typing by ERIC-PCR detected 38 genetic profiles, demonstrating a multiclonal spread of the isolates analyzed. It was observed that the virulence genes irp2, mrkD, and fimH were seen to have together a higher frequency in the KPC-positive group. The accumulation of virulence genes of KPC-positive K. pneumoniae isolates, observed in this study, along with the multi-resistance impose significant therapeutic limitations on the treatment of infections caused by K. pneumoniae. 相似文献
166.
Farzana Sabir Maria José Leandro Ana Paula Martins Maria C. Loureiro-Dias Teresa F. Moura Gra?a Soveral Catarina Prista 《PloS one》2014,9(8)
Aquaporins are membrane channels that facilitate the transport of water and other small molecules across the cellular membranes. We examined the role of six aquaporins of Vitis vinifera (cv. Touriga nacional) in the transport of water and atypical substrates (other than water) in an aqy-null strain of Saccharomyces cerevisiae. Their functional characterization for water transport was performed by stopped-flow fluorescence spectroscopy. The evaluation of permeability coefficients (Pf) and activation energies (Ea) revealed that three aquaporins (VvTnPIP2;1, VvTnTIP1;1 and VvTnTIP2;2) are functional for water transport, while the other three (VvTnPIP1;4, VvTnPIP2;3 and VvTnTIP4;1) are non-functional. TIPs (VvTnTIP1;1 and VvTnTIP2;2) exhibited higher water permeability than VvTnPIP2;1. All functional aquaporins were found to be sensitive to HgCl2, since their water conductivity was reduced (24–38%) by the addition of 0.5 mM HgCl2. Expression of Vitis aquaporins caused different sensitive phenotypes to yeast strains when grown under hyperosmotic stress generated by KCl or sorbitol. Our results also indicate that Vitis aquaporins are putative transporters of other small molecules of physiological importance. Their sequence analyses revealed the presence of signature sequences for transport of ammonia, boron, CO2, H2O2 and urea. The phenotypic growth variations of yeast cells showed that heterologous expression of Vitis aquaporins increased susceptibility to externally applied boron and H2O2, suggesting the contribution of Vitis aquaporins in the transport of these species. 相似文献
167.
168.
Jacqueline de Melo Barcelar Andrea Aliverti Catarina Rattes Maria Eduarda Ximenes Shirley Lima Campos Daniella Cunha Brand?o Guilherme Fregonezi Armèle Dornelas de Andrade 《PloS one》2014,9(11)
Objective
To analyze in obese women the acute effects of the breath stacking technique on thoraco-abdominal expansion.Design and Methods
Nineteen obese women (BMI≥30 kg/m2) were evaluated by anthropometry, spirometry and maximal respiratory muscle pressures and successively analyzed by Opto-Electronic Plethysmography and a Wright respirometer during quiet breathing and breath stacking maneuvers and compared with a group of 15 normal-weighted healthy women. The acute effects of the maneuvers were assessed in terms of total and compartmental chest wall volumes at baseline, end of the breath stacking maneuver and after the maneuver. Obese subjects were successively classified into two groups, accordingly to the response during the maneuver, group 1 = prevalent rib cage or group 2 = abdominal expansion.Results
Age was significantly lower in group 1 than group 2. When considering the two obese groups, FEV1 was lower and minute ventilation was higher only in group 2 compared to controls group. During breath stacking, inspiratory capacity was significant differences in obese subjects with a smaller expansion of the pulmonary rib cage and a greater expansion of the abdomen compared to controls and also between groups 1 and 2. A significant inverse linear relationship was found between age and inspiratory capacity of the pulmonary rib cage but not of the abdomen.Conclusions
In obese women the maximal expansion of the rib cage and abdomen is influenced by age and breath stacking maneuver could be a possible therapy for preventing respiratory complications. 相似文献169.
John A Corbin Vinay Bhaskar Ira D Goldfine Hassan Issafras Daniel H Bedinger Angela Lau Kristen Michelson Lisa M Gross Betty A Maddux Hua F Kuan Catarina Tran Llewelyn Lao Masahisa Handa Susan R Watson Ajay J Narasimha Shirley Zhu Raphael Levy Lynn Webster Sujeewa D Wijesuriya Naichi Liu Xiaorong Wu David Chemla-Vogel Steve R Lee Steve Wong Diane Wilcock Paul Rubin Mark L White 《MABS-AUSTIN》2014,6(1):262-272
Novel therapies are needed for the treatment of hypoglycemia resulting from both endogenous and exogenous hyperinsulinema. To provide a potential new treatment option, we identified XMetD, an allosteric monoclonal antibody to the insulin receptor (INSR) that was isolated from a human antibody phage display library. To selectively obtain antibodies directed at allosteric sites, panning of the phage display library was conducted using the insulin-INSR complex. Studies indicated that XMetD bound to the INSR with nanomolar affinity. Addition of insulin reduced the affinity of XMetD to the INSR by 3-fold, and XMetD reduced the affinity of the INSR for insulin 3-fold. In addition to inhibiting INSR binding, XMetD also inhibited insulin-induced INSR signaling by 20- to 100-fold. These signaling functions included INSR autophosphorylation, Akt activation and glucose transport. These data indicated that XMetD was an allosteric antagonist of the INSR because, in addition to inhibiting the INSR via modulation of binding affinity, it also inhibited the INSR via modulation of signaling efficacy. Intraperitoneal injection of XMetD at 10 mg/kg twice weekly into normal mice induced insulin resistance. When sustained-release insulin implants were placed into normal mice, they developed fasting hypoglycemia in the range of 50 mg/dl. This hypoglycemia was reversed by XMetD treatment. These studies demonstrate that allosteric monoclonal antibodies, such as XMetD, can antagonize INSR signaling both in vitro and in vivo. They also suggest that this class of allosteric monoclonal antibodies has the potential to treat hyperinsulinemic hypoglycemia resulting from conditions such as insulinoma, congenital hyperinsulinism and insulin overdose. 相似文献
170.
Development and characterisation of Brassica napus-Sinapis arvensis addition lines exhibiting resistance to Leptosphaeria maculans 总被引:2,自引:0,他引:2
R. J. Snowdon H. Winter A. Diestel M. D. Sacristán 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,101(7):1008-1014
Blackleg caused by Leptosphaeria maculans is one of the most important diseases affecting oilseed rape worldwide. Sinapis arvensis is valuable for the transfer of blackleg resistance to oilseed rape (Brassica napus) because this species contains high resistance against various aggressive isolates of the blackleg fungus. These include
at least one Australian isolate which has been found to overcome resistance originating from species with the Brassica B genome, until now the major source for interspecific transfer of blackleg resistance. Backcross offspring from intergeneric
crosses between Brassica napus and S. arvensis were subjected to phytopathological studies and molecular cytogenetic analysis with genomic in situ hybridisation (GISH). The BC3S progenies included fertile plants exhibiting high seedling (cotyledon) and adult plant resistance associated with the presence
of an acrocentric addition chromosome from S. arvensis. In addition, some individuals with adult plant resistance but cotyledon susceptibility were observed to have a normal B. napus karyotype with no visible GISH signals, indicating possible resistant introgression lines. Phytopathological analysis of
selfing progenies from 3 different highly resistant BC3 plants showed that seedling and adult plant resistance are probably conferred by different loci.
Received: 20 September 1999 / Accepted: 25 March 2000 相似文献