982 resultados para Electrophoretic mobility shift assays
Resumo:
Falls are a major concern in the elderly population with chronic joint disease. To compare muscular function and functional mobility among older women with knee osteoarthritis with and without a history of falls, 15 elderly women with a history of falls (74.20 ± 4.46 years) and 15 without a history of falls (71.73 ± 4.73 years) were studied. Muscular function, at the angular speed of 60, 120, and 180º/s, was evaluated using the Biodex Isokinetic Dynamometer. The sit-to-stand task was performed using the Balance Master System and the Timed Up and Go test was used to determine functional mobility. After collection of these data, the history of falls was investigated. A statistically significant difference was detected in the time taken to transfer the center of gravity during the sit-to-stand test (means ± SD; non-fallers: 0.35 ± 0.16 s; fallers: 0.55 ± 0.32 s; P = 0.049, Student t-test) and in the Timed Up and Go test (medians; non-fallers: 10.08 s; fallers: 11.59 s; P = 0.038, Mann-Whitney U-test). The results indicated that elderly osteoarthritic women with a history of falls presented altered functional mobility and needed more time to transfer the center of gravity in the sit-to-stand test. It is important to implement strategies to guarantee a better functional performance of elderly patients to reduce fall risks.
Resumo:
Hantavirus cardiopulmonary syndrome (HCPS) has been recognized as an important public heath problem. Five hantaviruses associated with HCPS are currently known in Brazil: Juquitiba, Araraquara, Laguna Negra-like, Castelo dos Sonhos, and Anajatuba viruses. The laboratory diagnosis of HCPS is routinely carried out by the detection of anti-hantavirus IgM and/or IgG antibodies. The present study describes the expression of the N protein of a hantavirus detected in the blood sample of an HCPS patient. The entire S segment of the virus was amplified and found to be 1858 nucleotides long, with an open reading frame of 1287 nucleotides that encodes a protein of 429 amino acids. The nucleotide sequence described here showed a high identity with the N protein gene of Araraquara virus. The entire N protein was expressed using the vector pET200D and the Escherichia coli BL21 strain. The expression of the recombinant protein was confirmed by the detection of a 52-kDa protein by Western blot using a pool of human sera obtained from HCPS patients, and by specific IgG detection in five serum samples of HCPS patients tested by ELISA. These results suggest that the recombinant N protein could be used as an antigen for the serological screening of hantavirus infection.
Resumo:
High mobility group box 1 (HMGB1) was discovered as a novel late-acting cytokine that contributes to acute lung injury (ALI). However, the contribution of HMGB1 to two-hit-induced ALI has not been investigated. To examine the participation of HMGB1 in the pathogenesis of ALI caused by the two-hit hypothesis, endotoxin was injected intratracheally in a hemorrhagic shock-primed ALI mouse model. Concentrations of HMGB1 in the lung of the shock group were markedly increased at 16 h (1.63 ± 0.05, compared to the control group: 1.02 ± 0.03; P < 0.05), with the highest concentration being observed at 24 h. In the sham/lipopolysaccharide group, lung HMGB1 concentrations were found to be markedly increased at 24 h (1.98 ± 0.08, compared to the control group: 1.07 ± 0.03; P < 0.05). Administration of lipopolysaccharide to the hemorrhagic shock group resulted in a notable HMGB1 increase by 4 h, with a further increase by 16 h. Intratracheal lipopolysaccharide injection after hemorrhagic shock resulted in the highest lung leak at 16 h (2.68 ± 0.08, compared to the control group: 1.05 ± 0.04; P < 0.05). Compared to the hemorrhagic shock/lipopolysaccharide mice, blockade of HMGB1 at the same time as lipopolysaccharide injection prevented significantly pulmonary tumor necrosis factor-alpha, interleukin-1beta and myeloperoxidase. Lung leak was also markedly reduced at 16 h; blockade of HMGB1 24 h after lipopolysaccharide injection failed to alter lung leak or myeloperoxidase at 48 h. Our observations suggest that HMGB1 plays a key role as a late mediator when lipopolysaccharide is injected after hemorrhagic shock-primed ALI and the kinetics of its release differs from that of one-hit ALI. The therapeutic window to suppress HMGB1 activity should not be delayed to 24 h after the disease onset.
Resumo:
The compounds 6-dimethylaminopurine and cycloheximide promote the successful production of cloned mammals and have been used in the development of embryos produced by somatic cell nuclear transfer. This study investigated the effects of 6-dimethylaminopurine and cycloheximide in vitro, using the thiazolyl blue tetrazolium bromide colorimetric assay to assess cytotoxicity, the trypan blue exclusion assay to assess cell viability, the comet assay to assess genotoxicity, and the micronucleus test with cytokinesis block to test mutagenicity. In addition, the comet assay and the micronucleus test were also performed on peripheral blood cells of 54 male Swiss mice, 35 g each, to assess the effects of the compounds in vivo. The results indicated that both 6-dimethylaminopurine and cycloheximide, at the concentrations and doses tested, were cytotoxic in vitro and genotoxic and mutagenic in vitro and in vivo, altered the nuclear division index in vitro, but did not diminish cell viability in vitro. Considering that alterations in DNA play important roles in mutagenesis, carcinogenesis, and morphofunctional teratogenesis and reduce embryonic viability, this study indicated that 6-dimethylaminopurine and cycloheximide utilized in the process of mammalian cloning may be responsible for the low embryo viability commonly seen in nuclear transfer after implantation in utero.
Resumo:
In this study, we investigated the potential role of high-mobility group box 1 (HMGB1) in severe acute pancreatitis (SAP) and the effects of growth hormone (G) and somatostatin (S) in SAP rats. The rats were randomly divided into 6 groups of 20 each: sham-operated, SAP, SAP+saline, SAP+G, SAP+S and SAP+G+S. Ileum and pancreas tissues of rats in each group were evaluated histologically. HMGB1 mRNA expression was measured by reverse transcription-PCR. Levels of circulating TNF-α, IL-1, IL-6, and endotoxin were also measured. In the SAP group, interstitial congestion and edema, inflammatory cell infiltration, and interstitial hemorrhage occurred in ileum and pancreas tissues. The levels of HMGB1, TNF-α, IL-1, IL-6 and endotoxin were significantly up-regulated in the SAP group compared with those in the sham-operated group, and the 7-day survival rate was 0%. In the SAP+G and SAP+S groups, the inflammatory response of the morphological structures was alleviated, the levels of HMGB1, TNF-α, IL-1, IL-6, and endotoxin were significantly decreased compared with those in the SAP group, and the survival rate was increased. Moreover, in the SAP+G+S group, all histological scores were significantly improved and the survival rate was significantly higher compared with the SAP group. In conclusion, HMGB1 might participate in pancreas and ileum injury in SAP. Growth hormone and somatostatin might play a therapeutic role in the inflammatory response of SAP.
Resumo:
Polyacrylamide gel electrophoresis, SDS-PAGE system, was adjusted to detect the presence of additional whey in dairy beverages distributed in a Brazilian Government School Meals Program. Aqueous solutions of samples in 8 M urea were submitted to a polyacrylamide gel gradient (10% to 18%). Gel scans from electrophoresis patterns of previously adulterated milk samples showed that caseins peak areas decreased while peak areas of beta -lactoglobulin plus alpha -lactalbumin increased as the percentage of raw milk powder replaced by whey powder increased. The relative densitometer areas of caseins or beta -lactoglobulin plus alpha -lactalbumin plotted against the percentage of whey added to the raw milk showed a linear correlation coefficient square higher than 0.97. The caseins plot was used to determine the percentage of additional whey in 116 dairy beverages, chocolate or coffee flavor. Considering that the lowest relative caseins concentration found in commercial milk powder samples by the present method was 72%, the dairy beverages containing caseins percentages equal to or higher than this value were considered free of additional whey. Based on this criterion, about 49% of the coffee-flavor dairy beverages and 29% of the chocolate-flavor beverages, among all the samples analyzed were adulterated with whey protein to reach the total protein contents specified on their labels. The present method showed a sensitivity of 5% to additional whey.
Resumo:
This paper reexamines the issue of international financial capital mobility, which is today's economic orthodoxy. Discussion is often framed in terms of the impossible trinity. That framing distorts discussion by representing capital mobility as having equal significance with sovereign monetary policy and control over exchange rates. It also distorts discussion by ignoring possibilities for coordinated monetary policy and exchange rates, and for managed capital flows. The case for capital mobility rests on neo-classical economic efficiency arguments and neo-liberal political arguments. The case against capital mobility is based on Keynesian macroeconomic inefficiency arguments, neo-Walrasian market failure arguments, and neo-Marxian arguments regarding distortion of the social structure of accumulation. Close examination shows the case for capital mobility to be extremely flimsy, pointing to the ideological dimension behind today's policy orthodoxy.
Resumo:
Textbook theory ignores capital flows: trade determines exchange rates and specialisation. Approaches taking the effects of capital movements adequately into account are needed, and a new theory of economic policy including measures to protect the real economy from external volatility. Equilibrating textbook mechanisms cannot work unless trade-caused surpluses and deficits set exchange rates. To allow orthodox trade theory to work one must hinder capital flows from destroying its very basis, which the IMF and wrong regulatory decisions have done, penalising production and trade. A new, real economy based theory is proposed, a Neoclassical agenda of controlling capital flows and speculation.
Resumo:
The negotiations between the EU and the US over the Transatlantic Trade and Investment Partnership (TTIP) have generated a lot of discussion about investor-state dispute settlement (ISDS). This discussion provided the inspiration for this thesis, with the TTIP in the background, setting the scene. In this thesis I study the nature of ISDS and the principle of transparency within investor-state arbitration. I aim to determine whether the use of ISDS is restricted to international arbitration and whether ISDS can be considered to constitute a system or regime. Furthermore, I consider whether the introduction of the UNCITRAL Rules on Transparency in Treaty-based Investor-State Arbitration (2014, the UNCITRAL Transparency Rules) changes investor-state arbitration in relation to transparency. To achieve this, I examine ISDS provisions in several different international investment agreements (IIAs) and evaluate the ways in which transparency is incorporated into investment law. Moreover, I compare the provisions on transparency and confidentiality in institutional arbitration rules with the UNCITRAL Transparency Rules. I have formed several conclusions, including that the ISDS provisions may contain methods other than international arbitration and that ISDS does not constitute a system. Furthermore, the UNCITRAL Transparency Rules do change – theoretically, at least – investor-state arbitration to become more transparent. Whether the UNCITRAL Transparency Rules will make investor-state arbitration fully transparent depends on the actions of the contracting state parties when negotiating new IIAs and whether they choose to incorporate the UNCITRAL Transparency Rules in the IIAs already concluded.
Resumo:
In the work reported here, optically clear, ultrathin TEOS derived sol-gel slides which were suitable for studies of tryptophan (Trp) fluorescence from entrapped proteins were prepared by the sol-gel technique and characterized. The monitoring of intrinsic protein fluorescence provided information about the structure and environment of the entrapped protein, and about the kinetics of the interaction between the entrapped protein and extemal reagents. Initial studies concentrated on the single Trp protein monellin which was entrapped into the sol-gel matrices. Two types of sol-gel slides, termed "wet aged", in which the gels were aged in buffer and "dry-aged", in which the gels were aged in air , were studied in order to compare the effect of the sol-gel matrix on the structure of the protein at different aging stages. Fluorescence results suggested that the mobility of solvent inside the slides was substantially reduced. The interaction of the entrapped protein with both neutral and charged species was examined and indicated response times on the order of minutes. In the case of the neutral species the kinetics were diffusion limited in solution, but were best described by a sum of first order rate constants when the reactions occurred in the glass matrix. For charged species, interactions between the analytes and the negatively charged glass matrix caused the reaction kinetics to become complex, with the overall reaction rate depending on both the type of aging and the charge on the analyte. The stability and conformational flexibility of the entrapped monellin were also studied. These studies indicated that the encapsulation of monellin into dry-aged monoliths caused the thermal unfolding transition to broaden and shift upward by 14°C, and causedthe long-term stability to improve by 12-fold (compared to solution). Chemical stability studies also showed a broader transition for the unfolding of the protein in dry-aged monoliths, and suggested that the protein was present in a distribution of environments. Results indicated that the entrapped proteins had a smaller range of conformational motions compared to proteins in solution, and that entrapped proteins were not able to unfold completely. The restriction of conformational motion, along with the increased structural order of the internal environment of the gels, likely resulted in the improvements in themial and long-term stability that were observed. A second protein which was also studied in this work is the metal binding protein rat oncomodulin. Initially, the unfolding behavior of this protein in aqueous solution was examined. Several single tryptophan mutants of the metal-binding protein rat oncomodulin (OM) were examined; F102W, Y57W, Y65W and the engineered protein CDOM33 which had all 12 residues of the CD loop replaced with a higher affinity binding loop. Both the thermal and the chemical stability were improved upon binding of metal ions with the order apo < Ca^^ < Tb^"^. During thermal denaturation, the transition midpoints (Tun) of Y65W appeared to be the lowest, followed by Y57W and F102W. The placement of the Trp residue in the F-helix in F102W apparently made the protein slightly more thermostable, although the fluorescence response was readily affected by chemical denaturants, which probably acted through the disruption of hydrogen bonds at the Cterminal end of the F-helix. Under both thermal and chemical denaturation, the engineered protein showed the highest stability. This indicated that increasing the number of metal ligating oxygens in the binding site, either by using a metal ion with a higher coordinatenumber (i.e. Tb^*) which binds more carboxylate ligands, or by providing more ligating groups, as in the CDOM33 replacement, produces notable improvements in protein stability. Y57W and CE)OM33 OM were chosen for further studies when encapsulated into sol-gel derived matrices. The kinetics of interaction of terbium with the entrapped proteins, the ability of the entrapped protein to binding terbium, as well as thermal stability of these two entrapped protein were compared with different levels of Ca^"*^ present in the matrix and in solution. Results suggested that for both of the proteins, the response time and the ability to bind terbium could be adjusted by adding excess calcium to the matrix before gelation. However, the less stable protein Y57W only retained at most 45% of its binding ability in solution while the more stable protein CDOM33 was able to retain 100% binding ability. Themially induced denaturation also suggested that CDOM33 showed similar stability to the protein in solution while Y57W was destabilized. All these results suggested that "hard" proteins (i.e. very stable) can easily survive the sol-gel encapsulation process, but "soft" proteins with lower thermodynamic stability may not be able to withstand the sol-gel process. However, it is possible to control many parameters in order to successfully entrap biological molecules into the sol-gel matrices with maxunum retention of activity.
Resumo:
A Gram negative aerobic flagellated bacterium with fungal growth inhibitory properties was isolated from a culture of Trichoderma harzianum. According to its cultural characteristics and biochemical properties it was identified as a strain of Alcaligenes (aeca/is Castellani and Chalmers. Antisera prepared in Balbc mice injected with live and heat-killed bacterial cells gave strong reactions with the homologous immunogen and with ATCC 15554, the type strain of A. taeca/is, but not with Escherichia coli or Enterobacter aerogens in immunoprecipitation and dot immunobinding assays. Growth of Botrytis cinerea Pers. and several other fungi was significantly affected when co-cultured with A. taeca/is on solid media. Its detrimental effect on germination and growth of B. cinerea has been found to be associated with antifungal substances produced by the bacterium and released into the growth medium. A biotest for the antibiotic substances, based on their inhibitory effect on germination of B. cinerea conidia, was developed. This biotest was used to study the properties of these substances, the conditions in which they are produced, and to monitor the steps of their separation during extraction procedures. It has been found that at least two substances could be involved in the antagonistic interaction. One of these is a basic volatile substance and has been identified as ammonia. The other substance is a nonvolatile, dialysable, heat stable, polar compound released into the growth medium. After separation of growth medium samples by Sephadex G-10 column chromatography a single peak with a molecular weight below 700 Daltons exhibited inhibitory activity. From its behaviour in electrophoretic separation in agarose gels it seems that this is a neutral or slightly positively charged.
Resumo:
This qualitative study was designed to inquire about the barriers to participation within the fitness industry for people living with mobility challenges. i\n examination of the insights, stolies~ and experiences with barriers through interviews gi ven by 4 people living with mobility challenges (PMC) formed the core of the research. An analysis of the interviews from the 4 PMC informants was performed at t\\/O levels. First, a content analysis served to identify general and specific categories related to barrier issues within various fitness environments. Secondly, in-depth thematic analyses of the entries related to the insights and stories from the 4 informants which emerged from the content analysis of the data gave rise to fi ve thematic statements. From the thematic statements a fitness industry awareness protocol was created in the fonn of a statement response questionnaire. The protocol, which was given to 4 fitness assessors/trainers, \vas used to provide a snapshot of the fitness industry's readiness to work vvith disability. Throughout the process, the four PNIC informants formed a collaborati vely involved group of coresearchers, adding their voices to the narrative of the fitness-barrier experience. The result of the study suggests that barriers to participation within the fitness industry for PMC exist in various forms and levels of severity. The results also suggest that the fitness industry needs to better prepare their people and environment for working with people with physical disabilities, such as PMC, and provide a more open and positi ve environment for participation. Within the context of any fitness-related environment, recognizing that barriers to participation do exist, and acknowledging and accepting people with disabilities for who they are as indi viduals, will serve to develop a relationship where fitness practitioners and people with disabilities can work towards creating an inviting, inclusive, accessible, and barrier-free fitness environment for all.