Analysis of LEDGF/p75 expression regulation

Background To replicate, retroviruses must insert DNA copies of their RNA genomes into the host genome. This integration process is catalyzed by the viral integrase protein. The site of viral integration has been shown to be non-random and retrovirus-specific. LEDGF/p75, a splice variant encoded by PSIP1 gene and described as a general transcription coactivator, was identified as a tethering factor binding both to chromatin and to lentiviral integrases, thereby affecting integration efficiency as well as integration site selection. LEDGF/p75 is still a poorly characterized protein, and its cellular endogenous function has yet to be fully determined. In order to start unveiling the roles of LEDGF/p75 in the cell, we started to investigate the mechanisms involved in the regulation of LEDGF/p75. Materials and methods To identify PSIP1 minimal promoter and associated regulatory elements, we cloned a region starting 5 kb upstream the transcription start site (TSS, +1 reference position) to the ATG start codon (+816), as well as systematic truncations, in a plasmid containing the firefly luciferase reporter gene. These constructs were co-transfected into HEK293 cells with a plasmid encoding the Renilla luciferase under the pTK promoter as an internal control for transfection efficiency. Both luciferase activities were assessed by luminescence as an indicator of promoter activity. Results Luciferase assays identified regions -76 to +1 and +1 to +94 as two independent minimal promoters showing respectively a 3.7x and 2.3x increase in luciferase activity. These two independent minimal promoters worked synergistically increasing luciferase activity up to 16.3x as compared to background. Moreover, we identified five regulatory blocks which modulated luciferase activity depending on the DNA region tested, three enhancers (- 2007 to -1159, -284 to -171 and +94 to +644) and two silencers (-171 to -76 and +796 to +816). However, the silencing effect of the region -171 to -76 is dependent on the presence of the +94 to +644 region, ruling out the enhancer activity of the latter. Computational analysis of PSIP1 promoter revealed the absence of TATA box and initiator (INR) sequences, classifying this promoter as nonconventional. TATA-less and INR-less promoters are characterized by multiple Sp1 binding sites, involved in the recruitment of the RNA pol II complex. Consistent with this, PSIP1 promoter contains multiple putative Sp1 binding sequences in regions -76 to +1 and +1 to +94.

Kilpailija-analyysi Keravan ruokaravintoloista

Opinn��ytety��n tavoitteena oli luoda kilpailija-analyysi Keravan keskustan ruokaravintoloista. Opinn��ytety��n toimeksiantaja oli perheyritys HS Ravintolat KY jolla on ollut alustavia suunnitelmia perustaa lounasravintola esimerkiksi Keravalle. Ennen ravintolan perustamista yritys halusi selvitt���� mink��laisia ravintoloita kyseisill�� markkinoilla on. Opinn��ytety��ss�� haluttiin my��s tutkia Keravan keskustan ruokaravintoloiden kilpailutilannetta. Lis��ksi haettiin vastausta kysymykseen, onko n��ill�� ruokaravintolamarkkinoilla tilaa uudelle yksityiselle lounasravintolalle. Tutkimuksessa kartoitettiin kaikki Keravalla sijaitsevat ravintolat ja jaettiin ne seuraaviin ryhmiin: baarit, pizzeriat, kebabravintolat, pikaruokalat, grillit, kahvilat, kahvilaravintolat, lounasravintolat ja ravintolat. Kilpailija-analyysi tehtiin niist�� ravintoloista ja kahviloista jotka sijaitsivat 04200 postitoimialueella eli noin kilometrin s��teell�� toisistaan Keravan keskustassa. Kaikissa keskustan ravintoloissa ja kahviloissa vierailtiin ja vierailujen aikana vastattiin etuk��teen laadittuun kyselylomakkeeseen. Lomakkeessa selvitettiin muun muassa ravintoloiden asiakaskuntaa, tuotevalikoimaa, tavoitteita, oletuksia ja arvomaailmaa. Perustettavan ravintolan t��rkeimmist�� kilpailijoista tehtiin my��s SWOT-analyysi. Tutkimus suoritettiin Keravalla kahtena p��iv��n�� syksyll�� 2006 ja yhten�� p��iv��n�� kev����ll�� 2007. Tutkimustuloksista selvisi, ett�� Keravalla on yhteens�� 58 ravintolaksi luokiteltavaa paikkaa joista yli 62% sijaitsee keskustan alueella. Kilpailija-analyysiin kelpuutettiin keskustassa sijaitsevat ravintolat ja kahvilat. Toimipaikkoja l��ytyi yhteens�� 17 ja niist�� seitsem��n oli kahviloita. Keskustan 10:st�� ravintolasta per��ti kuusi oli teemaravintoloita ja seitsem��st�� kahvilasta vain kaksi oli perinteisiksi kahviloiksi luokiteltavia. Lis��ksi keskustan ravintolat ja kahvilat olivat erilaistaneet toimintaansa muun muassa pitopalvelulla, kabinettien ja astioiden vuokrauksella sek�� yksityistilaisuuksilla. N��m�� erilaistamisen toimet kertoivat ravintoloiden v��lisest�� kovasta kilpailusta. Opinn��ytety��n teoreettinen osuus k��sitteli kilpailija-analyysi�� ja erilaisia kilpailija-analyysimalleja. Analyysimalleissa keskityttiin eniten Porterin malliin. Teoriaosuudessa k��siteltiin my��s asiakasmarkkinointia ja erityisesti markkinoinnin osa-alueita segmentointia ja asemointia. Opinn��ytety��n pohdintaosuudessa mietittiin, mink��laisella ravintolalla tai kahvilalla olisi mahdollisuuksia menesty�� Keravan ruokaravintolamarkkinoilla.

Rules of origin : from analysis to reform

General Introduction This thesis can be divided into two main parts :the first one, corresponding to the first three chapters, studies Rules of Origin (RoOs) in Preferential Trade Agreements (PTAs); the second part -the fourth chapter- is concerned with Anti-Dumping (AD) measures. Despite wide-ranging preferential access granted to developing countries by industrial ones under North-South Trade Agreements -whether reciprocal, like the Europe Agreements (EAs) or NAFTA, or not, such as the GSP, AGOA, or EBA-, it has been claimed that the benefits from improved market access keep falling short of the full potential benefits. RoOs are largely regarded as a primary cause of the under-utilization of improved market access of PTAs. RoOs are the rules that determine the eligibility of goods to preferential treatment. Their economic justification is to prevent trade deflection, i.e. to prevent non-preferred exporters from using the tariff preferences. However, they are complex, cost raising and cumbersome, and can be manipulated by organised special interest groups. As a result, RoOs can restrain trade beyond what it is needed to prevent trade deflection and hence restrict market access in a statistically significant and quantitatively large proportion. Part l In order to further our understanding of the effects of RoOs in PTAs, the first chapter, written with Pr. Olivier Cadot, Celine Carr��re and Pr. Jaime de Melo, describes and evaluates the RoOs governing EU and US PTAs. It draws on utilization-rate data for Mexican exports to the US in 2001 and on similar data for ACP exports to the EU in 2002. The paper makes two contributions. First, we construct an R-index of restrictiveness of RoOs along the lines first proposed by Estevadeordal (2000) for NAFTA, modifying it and extending it for the EU's single-list (SL). This synthetic R-index is then used to compare Roos under NAFTA and PANEURO. The two main findings of the chapter are as follows. First, it shows, in the case of PANEURO, that the R-index is useful to summarize how countries are differently affected by the same set of RoOs because of their different export baskets to the EU. Second, it is shown that the Rindex is a relatively reliable statistic in the sense that, subject to caveats, after controlling for the extent of tariff preference at the tariff-line level, it accounts for differences in utilization rates at the tariff line level. Finally, together with utilization rates, the index can be used to estimate total compliance costs of RoOs. The second chapter proposes a reform of preferential Roos with the aim of making them more transparent and less discriminatory. Such a reform would make preferential blocs more "cross-compatible" and would therefore facilitate cumulation. It would also contribute to move regionalism toward more openness and hence to make it more compatible with the multilateral trading system. It focuses on NAFTA, one of the most restrictive FTAs (see Estevadeordal and Suominen 2006), and proposes a way forward that is close in spirit to what the EU Commission is considering for the PANEURO system. In a nutshell, the idea is to replace the current array of RoOs by a single instrument- Maximum Foreign Content (MFC). An MFC is a conceptually clear and transparent instrument, like a tariff. Therefore changing all instruments into an MFC would bring improved transparency pretty much like the "tariffication" of NTBs. The methodology for this exercise is as follows: In step 1, I estimate the relationship between utilization rates, tariff preferences and RoOs. In step 2, I retrieve the estimates and invert the relationship to get a simulated MFC that gives, line by line, the same utilization rate as the old array of Roos. In step 3, I calculate the trade-weighted average of the simulated MFC across all lines to get an overall equivalent of the current system and explore the possibility of setting this unique instrument at a uniform rate across lines. This would have two advantages. First, like a uniform tariff, a uniform MFC would make it difficult for lobbies to manipulate the instrument at the margin. This argument is standard in the political-economy literature and has been used time and again in support of reductions in the variance of tariffs (together with standard welfare considerations). Second, uniformity across lines is the only way to eliminate the indirect source of discrimination alluded to earlier. Only if two countries face uniform RoOs and tariff preference will they face uniform incentives irrespective of their initial export structure. The result of this exercise is striking: the average simulated MFC is 25% of good value, a very low (i.e. restrictive) level, confirming Estevadeordal and Suominen's critical assessment of NAFTA's RoOs. Adopting a uniform MFC would imply a relaxation from the benchmark level for sectors like chemicals or textiles & apparel, and a stiffening for wood products, papers and base metals. Overall, however, the changes are not drastic, suggesting perhaps only moderate resistance to change from special interests. The third chapter of the thesis considers whether Europe Agreements of the EU, with the current sets of RoOs, could be the potential model for future EU-centered PTAs. First, I have studied and coded at the six-digit level of the Harmonised System (HS) .both the old RoOs -used before 1997- and the "Single list" Roos -used since 1997. Second, using a Constant Elasticity Transformation function where CEEC exporters smoothly mix sales between the EU and the rest of the world by comparing producer prices on each market, I have estimated the trade effects of the EU RoOs. The estimates suggest that much of the market access conferred by the EAs -outside sensitive sectors- was undone by the cost-raising effects of RoOs. The chapter also contains an analysis of the evolution of the CEECs' trade with the EU from post-communism to accession. Part II The last chapter of the thesis is concerned with anti-dumping, another trade-policy instrument having the effect of reducing market access. In 1995, the Uruguay Round introduced in the Anti-Dumping Agreement (ADA) a mandatory "sunset-review" clause (Article 11.3 ADA) under which anti-dumping measures should be reviewed no later than five years from their imposition and terminated unless there was a serious risk of resumption of injurious dumping. The last chapter, written with Pr. Olivier Cadot and Pr. Jaime de Melo, uses a new database on Anti-Dumping (AD) measures worldwide to assess whether the sunset-review agreement had any effect. The question we address is whether the WTO Agreement succeeded in imposing the discipline of a five-year cycle on AD measures and, ultimately, in curbing their length. Two methods are used; count data analysis and survival analysis. First, using Poisson and Negative Binomial regressions, the count of AD measures' revocations is regressed on (inter alia) the count of "initiations" lagged five years. The analysis yields a coefficient on measures' initiations lagged five years that is larger and more precisely estimated after the agreement than before, suggesting some effect. However the coefficient estimate is nowhere near the value that would give a one-for-one relationship between initiations and revocations after five years. We also find that (i) if the agreement affected EU AD practices, the effect went the wrong way, the five-year cycle being quantitatively weaker after the agreement than before; (ii) the agreement had no visible effect on the United States except for aone-time peak in 2000, suggesting a mopping-up of old cases. Second, the survival analysis of AD measures around the world suggests a shortening of their expected lifetime after the agreement, and this shortening effect (a downward shift in the survival function postagreement) was larger and more significant for measures targeted at WTO members than for those targeted at non-members (for which WTO disciplines do not bind), suggesting that compliance was de jure. A difference-in-differences Cox regression confirms this diagnosis: controlling for the countries imposing the measures, for the investigated countries and for the products' sector, we find a larger increase in the hazard rate of AD measures covered by the Agreement than for other measures.

Implementa����o e valida����o de um m��todo cromatogr��fico para a Detec����o e Quantifica����o de Furano em Feij��o Enlatado

O furano tem sido detectado em diversos alimentos em particular nos que s��o sujeitos a tratamento t��rmico durante o processo de prepara����o industrial. �� considerado um composto potencialmente cancer��geno para seres humanos, pelo que a sua presen��a nos alimentos se tornou uma quest��o de seguran��a alimentar. Desde 2007 que a Autoridade Europeia para a Seguran��a Alimentar tem procurado recolher o maior n��mero de informa����o poss��vel, relativa �� presen��a de furano nos alimentos. Neste trabalho utilizou-se a t��cnica de Cromatografia Gasosa de Espa��o de Cabe��a acoplada a um espectr��metro de massa (HS-GC/MS) para avaliar os teores de furano em feij��es enlatados. Foram analisadas 10 amostras (latas) independentes, seleccionadas aleatoriamente no mercado, de tr��s marcas comercializadas em Portugal. A concentra����o m��dia obtida foi de 3,27 ng/g, numa gama que variou entre 2,61 e 4,45 ng/g. Os limites de detec����o calculados foram de 0,80 ng/g para as amostras PD, 1,26 ng/g para as amostras C e de 0,58 ng/g para as amostras F. Os limites de quantifica����o foram, respectivamente, de 2,44, 3,82 e 1,77 ng/g. Os coeficientes de varia����o do m��todo foram inferiores a 10% e a percentagem de recupera����o foi de 95%. Para estudar o efeito do tratamento t��rmico dom��stico, foram tamb��m, analisadas amostras aquecidas �� temperatura de 80��C, tendo-se verificado um aumento significativo na concentra����o do furano detectada. Comparou-se ainda a concentra����o m��dia do furano obtido nos feij��es em lata com a concentra����o m��dia para o mesmo tipo de feij��o conservado em frascos de vidro, tendose constatado n��o existirem diferen��as significativas.

Cis-configured aziridines are new pseudo-irreversible dual-mode inhibitors of Candida albicans secreted aspartic protease 2

A series of cis-configured epoxides and aziridines containing hydrophobic moieties and amino acid esters,were synthesized as new potential inhibitors of the secreted aspartic protease 2 (SAP2) of Candida albicans. Enzyme assays revealed the N- benzyl-3-phenyl-substituted aziridines 11 and 17 as the most potent inhibitors, with second-order inhibition, rate constants (k(2)) between 56000 and 12-1000 M-1 min(-1). The compounds were shown to be pseudo-irreversible dual-mode, inhibitors: the interm ediate esterified enzyme resulting from nucleophilic ring opening was hydrolyzed and yielded amino alcohols as transition state-mimetic reversible inhibitors. The results of docking studies with the ring-closed aziridine forms of the inhibitors suggest binding modes mainly dominated by hydrophobic interactions with the S1, S1' S2, and S2' subsites of the protease, and docking studies with the processed amino alcohol forms predict additional hydrogen bonds of the new hydroxy group to the active site Asp residues. C. albicans growth assays showed the compounds to decrease SAP2-dependent growth while not affecting SAP2-independent growth.

Handgrip strength and physical activity in frail elderly

Abstract OBJECTIVE To investigate the association between handgrip strength (HS) and physical activity in physical frailty elderly. METHOD Cross-sectional quantitative study with a sample of 203 elderly calculated based on the population estimated proportion. Tests were applied to detect cognitive impairment and assessment of physical frailty. Descriptive statistics and multivariate analysis by binary logistic regression were used, and also Student's t-test and Fisher's exact test. RESULTS A total of 99 (64.3%) elderly showed decreased handgrip strength and 90 (58.4%) elderly presented decrease in physical activity levels. There was a statistically significant difference between these two components (p=0.019), in which elderly who have decreased HS have lower levels of physical activity. For low levels of physical activity and decreased HS, there was no evidence of significant difference in the probability of the classification as frail elderly (p<0.001). CONCLUSION The components handgrip strength and physical activity are associated with the frail elderly. The joint presence of low levels of physical activity and decreased handgrip strength leads to a significantly higher probability of the elderly to be categorized as frailty.

Aging and the lateralization of oscillatory activities related to external and internal motor preparation

Selection of action may rely on external guidance or be motivated internally, engaging partially distinct cerebral networks. With age, there is an increased allocation of sensorimotor processing resources, accompanied by a reduced differentiation between the two networks of action selection. The present study examines the age effects on the motor-related oscillatory patterns related to the preparation of externally and internally guided movements. Thirty-two older and 30 younger adults underwent three delayed motor tasks with S1 as preparatory and S2 as imperative cue: Full, laterality instructed by S1 (external guidance); Free, laterality freely selected (internal guidance); None, laterality instructed by S2 (no preparation). Electroencephalogram (EEG) was recorded using 64 surface electrodes. Motor-Related Amplitude Asymmetries (MRAA), indexing the lateralization of oscillatory activities, were analyzed within the S1-S2 interval in the mu (9-12 Hz) and low beta (15-20 Hz) motor-related frequency bands. Reaction times to S2 were slower in older than younger subjects, and slower in the Free than in the Full condition in older subjects only. In the Full condition, there were significant mu MRAA in both age groups, and significant low beta MRAA only in older adults. The Free condition was associated with large mu MRAA in younger adults and limited low beta MRAA in older adults. In younger subjects, the lateralization of mu activity in both Full and Free conditions indicated effective external and internal motor preparation. In older subjects, external motor preparation was associated with lateralization of low beta in addition with mu activity, compatible with an increase of motor-related resources. In contrast, absence of mu and limited low beta lateralization in internal motor preparation was concomitant with reaction time slowing and suggested less efficient cerebral processes subtending free movement selection in older adults, indicating reduced capacity for internally driven action with age.

The presence of a CD4+ CD25high CD45RO+ CD127high T-cell population correlates with the clinical status of kidney transplant recipients

Background: Recent data have suggested that a population of CD4+ CD25high T cells, phenotypically characterized by the expression of CD45RO and CD127, is significantly expanded in stable liver and kidney transplant recipients and represents alloreactive T cells. We analyzed this putative new alloreactive cellular marker in various groups of kidney transplant recipients. Patients and methods: Flow cytometry was used to analyze the expression of CD25, CD45RO and CD127 on peripheral CD4+ T cells. Of 73 kidney recipients, 59 had a stable graft function under standard immunosuppressive therapy (IS), 5 had biopsy-proven chronic humoral rejection (CHR), 8 were stable under minimal IS and one was an operationally "tolerant" patient who had discontinued IS for more than 3 years. Sixty-six healthy subjects (HS) were studied as controls. Results: Overall, the alloreactive T cell population was found to be significantly increased in the 73 kidney recipients (mean �� SE: 15.03 �� 1.04% of CD4+ CD25high T cells) compared to HS (5.93 �� 0.39%) (p &lt;0.001). In the 5 patients with CHR, this population was highly expanded (31.33 �� 4.16%), whereas it was comparable to HS in the 8 stable recipients receiving minimal IS (6.12 �� 0.86%), in 4 patients who had been switched to sirolimus (4.21 �� 0.53%) as well as in the unique "tolerant" recipient (4.69%). Intermediate levels (15.84 �� 0.93%) were found in the 55 recipients with stable graft function on standard CNI-based IS. Regulatory T cells, defined as CD4+ CD25high FoxP3+ CD127low, were found to be significantly reduced in all recipients except in those with minimal or no IS, and this reduction was particularly striking in recipients with CHR. Conclusion: After kidney transplantation, an alloreactive T cell population was found to be significantly expanded and it correlates with the clinical status of the recipients. Interestingly, in stable patients with minimal (or no) IS as well as in patients on sirolimus, alloreactive T cells were comparable the healthy controls. Measuring circulating CD4+ CD25high CD45RO+ CD127high T cells may become a useful monitoring tool after transplantation.

Allergy to betalactam antibiotics in children: a prospective follow-up study in retreated children after negative responses in skin and challenge tests.

BACKGROUND: Up to 10% of the patients in whom suspected betalactam hypersensitivity (HS) has been excluded by skin and challenge tests report suspected allergic reactions during subsequent treatments with the same or very similar betalactams. It has been suggested that the reactions may result from a resensitization induced by the challenge performed at the time of the allergological work-up. However, most patients did not undergo a second allergological work-up, to determine if the reactions resulted from betalactam HS or not. OBJECTIVES: We aimed to determine if children diagnosed nonallergic to betalactams have tolerated subsequent treatments with the initially suspected and/or other betalactams, and, in case of a reaction, if the reaction resulted from betalactam HS. Methods: We sent a questionnaire concerning the clinical history of their children to the parents of 256 children previously diagnosed nonallergic to betalactams. A second allergological work-up was performed in the children reporting suspected allergic reactions during subsequent treatments with the same and/or other betalactams. Skin tests were performed with the soluble form of the suspected (or very similar) betalactams and other betalactams from the same and other classes. Skin test responses were assessed at 15-20 min (immediate), 6-8 h (semi-late) and 48-72 h (late). Oral challenge (OC) was performed in children with negative skin tests, either at the hospital (immediate and accelerated reactions), or at home (delayed reactions). RESULTS: A response was obtained from 141 children (55.3%). Forty-eight (34%) of those children had not been treated with the betalactams for whom a diagnosis of allergy had been ruled out previously. Seven (7.5%) of the 93 children who had been treated again reported suspected allergic reactions. Skin tests and OC were performed in six of those children, and gave negative results in five children. In one child previously diagnosed nonallergic to amoxicillin associated with clavulanic acid, we diagnosed a delayed HS to clavulanic acid and a serum sickness-like disease to cefaclor. Thus, the frequency of reactions resulting from betalactam HS in children with negative skin and challenge tests is very low, and does not exceed 2.1% (2/93) if we consider that the child which refused a second allergological work-up is really allergic to betalactams. CONCLUSION: Our results in a very large number of children show that reactions presumed to result from betalactam HS are rare in children in whom the diagnosis of betalactam allergy has been ruled out previously. Moreover, they suggest that, as shown for the initial reactions, most of the reactions during subsequent treatments are rather a consequence of the infectious diseases for whom betalactams have been prescribed than a result of betalactam HS. Finally, they suggest that the risk of resensitization by OC is very low, and do not support the notion that skin testing should be repeated in children diagnosed nonallergic to betalactams.

A possible territorial or recognition behavior of Leptoglossus zonatus (Dallas) (Heteroptera, Coreidae)

The coreid Leptoglossus zonatus (Dallas, 1852) is commonly found in corn (Zea mays L.) fields in Brazil, and it has been observed flying and landing on objects or persons near these fields. During January, 1995, this behavior was studied in corn plantations. Results indicated that the bugs concentrated on objects (plastic cylinders traps) introduced into their habitat and that their number increased during the first 24 hs. However, as time passed (8 days), this possible territorial or recognition behavior gradually decreased, and tended to disappear.

Situa����o da Higiene e Seguran��a no Trabalho na Sociedade Cabo-verdiana de Cerveja e Refrigerantes: Estudo de caso

Esta pesquisa relaciona-se com a tem��tica Higiene e Seguran��a no Trabalho (HST). Por meio de question��rio com os funcion��rios da sociedade Cabo-verdiana de Cerveja e Refrigerantes (CERIS) e entrevista com o T��cnico de Recursos Humanos (TRH) da referida empresa, procuramos saber em que medida a exist��ncia das condi����es HST poder�� afectar a motiva����o do trabalhador e consequentemente conduzir a uma maior ou menor produtividade e desempenho no trabalho da CERIS. Para an��lise dos dados utilizamos tanto a metodologia quantitativa como qualitativa, pois recorremos ao inqu��rito por meio de question��rio e entrevista. Como resultado do estudo de caso, chegamos a conclus��o de que as condi����es de HST oferecido pela empresa n��o �� um factor que exerce muita influ��ncia e/ou motiva����o para a execu����o do trabalho, ou seja, as condi����es f��sicas do trabalho (ilumina����o, ru��do, vibra����es, entre outros), o reconhecimento profissional, o ambiente de trabalho, s��o consideradas pelos inquiridos como sendo factores que n��o contribuem para a motiva����o na execu����o das tarefas.

DETEC����O DE SUBPRODUTOS DA DESINFEC����O COM CLORO EM ��GUA DESSALINIZADA

A dessaliniza����o da ��gua do mar �� um m��todo usado para obter ��gua pot��vel. Na dessaliniza����o da ��gua tamb��m �� necess��ria a desinfec����o de ��gua com o cloro. Esta desinfec����o garante �� ��gua condi����es seguras em termos microbiol��gicos mas promove a forma����o de novas subst��ncias consideradas t��xicas, resultantes da reac����o do cloro com a mat��ria org��nica presente na ��gua. Essas subst��ncias s��o designados por subprodutos de desinfec����o de ��gua com o cloro (DBP) dos quais destacam-se os trihalometanos (THM), os ��cidos haloac��ticos (HAA), os haloacetonitrilos (HAN), as haloacetonas (HK). A concentra����o dessas subst��ncias em ��guas para consumo humano �� muito baixa e constitui sempre um desafio a sua detec����o e quantifica����o. Neste trabalho desenvolveu-se e optimizou-se m��todos de an��lises de DBP em ��gua para consumo humano. Os DBP vol��teis foram analisados por headspace e cromatografia gasosa com detec����o por captura electr��nica (HS-GC-ECD) e por microextrac����o em fase s��lida no headspace e cromatografia gasosa com detec����o por captura electr��nica (SPME-HS-GC-ECD). Para os DBP n��o vol��teis (HAA) aplicou-se a extrac����o em fase s��lida e cromatografia l��quida com detector de fila de diodos (SPE-RPHPLC- DAD). Foram analisados os DBP na ��gua dessalinizada por osmose inversa proveniente de Cabo Verde e na ��gua da cidade de Porto, de forma a verificar as diferen��as em termos qualitativos e quantitativos. Usou-se um planeamento factorial de Box-Behnken para a optimiza����o de m��todos anal��ticos. Este modelo foi igualmente aplicado na simula����o laboratorial de dessaliniza����o da ��gua do mar por osmose inversa e desinfec����o com o cloro, tendo como objectivo identificar os factores mais significativos na forma����o de DBP em ��gua dessalinizada (pH, temperatura e tempo de desinfec����o).

Effects of prior repeated-sprints with different recovery duration on oxygen uptake kinetics during subsequent heavy-exercise

Introduction: Prior repeated-sprints (6) has become an interesting method to resolve the debate surrounding the principal factors that limits the oxygen uptake (V'O2) kinetics at the onset of exercise [i.e., muscle O2 delivery (5) or metabolic inertia (3)]. The aim of this study was to compare the effects of two repeated-sprints sets of 6x6s separated by different recovery duration between the sprints on V'O2 and muscular de-oxygenation [HHb] kinetics during a subsequent heavy-intensity exercise. Methods: 10 male subjects performed a 6-min constant-load cycling test (T50) at intensity corresponding to half of the difference between V'O2max and the ventilatory threshold. Then, they performed two repeated-sprints sets of 6x6s all-out separated by different recovery duration between the sprints (S1:30s and S2:3min) followed, after 7-min-recovery, by the T50 (S1T50 and S2T50, respectively). V'O2, [HHb] of the vastus lateralis (VL) and surface electromyography activity [i.e., root-mean-square (RMS) and the median frequency of the power density spectrum (MDF)] from VL and vastus medialis (VM) were recorded throughout T50. Models using a bi-exponential function for the overall T50 and a mono-exponential for the first 90s of T50 were used to define V'O2 and [HHb] kinetics respectively. Results: V'O2 mean value was higher in S1 (2.9��0.3l.min-1) than in S2 (1.2��0.3l.min-1); (p<0.001). The peripheral blood flow was increased after sprints as attested by a higher basal heart rate (HRbaseline) (S1T50: +22%; S2T50: +17%; p&#8804;0.008). Time delay [HHb] was shorter for S1T50 and S2T50 than for T50 (-22% for both; p&#8804;0.007) whereas the mean response time of V'O2 was accelerated only after S1 (S1T50: 32.3��2.5s; S2T50: 34.4��2.6s; T50: 35.7��5.4s; p=0.031). There were no significant differences in RMS between the three conditions (p>0.05). MDF of VM was higher during the first 3-min in S1T50 than in T50 (+6%; p&#8804;0.05). Conclusion: The study show that V'O2 kinetics was speeded by prior repeated-sprints with a short (30s) but not a long (3min) inter-sprints-recovery even though the [HHb] kinetics was accelerated and the peripheral blood flow was enhanced after both sprints. S1, inducing a greater PCr depletion (1) and change in the pattern of the fibres recruitment (increase in MDF) compared with S2, may decrease metabolic inertia (2), stimulate the oxidative phosphorylation activation (4) and accelerate V'O2 kinetics at the beginning of the subsequent high-intensity exercise.

The dexamethasone-induced inhibition of proliferation, migration, and invasion in glioma cell lines is antagonized by macrophage migration inhibitory factor (MIF) and can be enhanced by specific MIF inhibitors.

Glioblastomas (GBMs) are the most frequent and malignant brain tumors in adults. Glucocorticoids (GCs) are routinely used in the treatment of GBMs for their capacity to reduce the tumor-associated edema. Few in vitro studies have suggested that GCs inhibit the migration and invasion of GBM cells through the induction of MAPK phosphatase 1 (MKP-1). Macrophage migration inhibitory factor (MIF), an endogenous GC antagonist is up-regulated in GBMs. Recently, MIF has been involved in tumor growth and migration/invasion and specific MIF inhibitors have been developed on their capacity to block its enzymatic tautomerase activity site. In this study, we characterized several glioma cell lines for their MIF production. U373 MG cells were selected for their very low endogenous levels of MIF. We showed that dexamethasone inhibits the migration and invasion of U373 MG cells, through a glucocorticoid receptor (GR)- dependent inhibition of the ERK1/2 MAPK pathway. Oppositely, we found that exogenous MIF increases U373 MG migration and invasion through the stimulation of the ERK1/2 MAP kinase pathway and that this activation is CD74 independent. Finally, we used the Hs 683 glioma cells that are resistant to GCs and produce high levels of endogenous MIF, and showed that the specific MIF inhibitor ISO-1 could restore dexamethasone sensitivity in these cells. Collectively, our results indicate an intricate pathway between MIF expression and GC resistance. They suggest that MIF inhibitors could increase the response of GBMs to corticotherapy.