935 resultados para post-transcriptional control
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INTRODUCTION: It is unclear to which level mean arterial blood pressure (MAP) should be increased during septic shock in order to improve outcome. In this study we investigated the association between MAP values of 70 mmHg or higher, vasopressor load, 28-day mortality and disease-related events in septic shock. METHODS: This is a post hoc analysis of data of the control group of a multicenter trial and includes 290 septic shock patients in whom a mean MAP > or = 70 mmHg could be maintained during shock. Demographic and clinical data, MAP, vasopressor requirements during the shock period, disease-related events and 28-day mortality were documented. Logistic regression models adjusted for the geographic region of the study center, age, presence of chronic arterial hypertension, simplified acute physiology score (SAPS) II and the mean vasopressor load during the shock period was calculated to investigate the association between MAP or MAP quartiles > or = 70 mmHg and mortality or the frequency and occurrence of disease-related events. RESULTS: There was no association between MAP or MAP quartiles and mortality or the occurrence of disease-related events. These associations were not influenced by age or pre-existent arterial hypertension (all P > 0.05). The mean vasopressor load was associated with mortality (relative risk (RR), 1.83; confidence interval (CI) 95%, 1.4-2.38; P < 0.001), the number of disease-related events (P < 0.001) and the occurrence of acute circulatory failure (RR, 1.64; CI 95%, 1.28-2.11; P < 0.001), metabolic acidosis (RR, 1.79; CI 95%, 1.38-2.32; P < 0.001), renal failure (RR, 1.49; CI 95%, 1.17-1.89; P = 0.001) and thrombocytopenia (RR, 1.33; CI 95%, 1.06-1.68; P = 0.01). CONCLUSIONS: MAP levels of 70 mmHg or higher do not appear to be associated with improved survival in septic shock. Elevating MAP >70 mmHg by augmenting vasopressor dosages may increase mortality. Future trials are needed to identify the lowest acceptable MAP level to ensure tissue perfusion and avoid unnecessary high catecholamine infusions.
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Post-Fordist economies come along with post-welfarist societies marked by intensified cultural individualism and increased structural inequalities. These conditions are commonly held to be conducive to relative deprivation and, thereby, anomic crime. At the same time, post-welfarist societies develop a new ‘balance of power’ between institutions providing for welfare regulation, such as the family, the state and the (labour) market – and also the penal system. These institutions are generally expected to improve social integration, ensure conformity and thus reduce anomic crime. Combining both perspectives, we analyse the effects of moral individualism, social inequality, and different integration strategies on crime rates in contemporary societies through the lenses of anomie theory. To test our hypotheses, we draw on time-series cross-section data compiled from different data sources (OECD, UN, WHO, WDI) for twenty developed countries in the period 1970-2004, and run multiple regressions that control for country-specific effects. Although we find some evidence that the mismatch between cultural ideal (individual inclusion) and structural reality (stratified exclusion) increases the anomic pressure, whereas conservative (i. e. family-based), social-democratic (i. e. state-based) and liberal (i. e. market-based) integration strategies to a certain extent prove effective in controlling the incidence of crime, the results are not very robust. Moreover, reservations have to be made regarding the effects of “market” income inequality as well as familialist, unionist and liberalist employment policies that are shown to have reversed effects in our sample: the former reducing, the latter occasionally increasing anomic crime. As expected, the mismatch between cultural ideal (individual inclusion) and structural reality (stratified exclusion) increases the anomic pressure, whereas conservative (i. e. family-based), social-democratic (i. e. state-based) and liberal (i. e. market-based) integration strategies generally prove effective in controlling the incidence of crime. Nevertheless, we conclude that the new cult of the individual undermines the effectiveness of conservative and social-democratic integration strategies and drives societies towards more “liberal” regimes that build on incentive as well as punitive elements.
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This paper introduces a database of freely available stereo-3D content designed to facilitate research in stereo post-production. It describes the structure and content of the database and provides some details about how the material was gathered. The database includes examples of many of the scenarios characteristic to broadcast footage. Material was gathered at different locations including a studio with controlled lighting and both indoor and outdoor on-location sites with more restricted lighting control. The database also includes video sequences with accompanying 3D audio data recorded in an Ambisonics format. An intended consequence of gathering the material is that the database contains examples of degradations that would be commonly present in real-world scenarios. This paper describes one such artefact caused by uneven exposure in the stereo views, causing saturation in the over-exposed view. An algorithm for the restoration of this artefact is proposed in order to highlight the usefuiness of the database.
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Teats of 36 ewes (72 udder halves or teats) were dipped with an experimental barrier - type teat dip product to evaluate product persistency post weaning. Persistency was evaluated one to two times/day and scored positive if the teat end orifice was covered and protected. Persistency or the percentage of teats covered/protected at 36, 54, 72, 96, 132, and 156 hours was 100%, 93%, 89%, 63%, 35%, and 24% respectively. Ewes will be dipped again pre-lambing and both persistency and bacteriology (mastitis prevention) will be evaluated compared to 36 control ewes.
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OBJECTIVES Pain control after thoracotomy is an important issue that affects the outcome in thoracic surgery. Intercostal nerve preservation (ICNP) has increased interest in the outcomes of conventional thoracotomy. The current study critically evaluates the role of preservation of the intercostal nerve in early and late pain control and its benefit in patients undergoing thoracotomy. METHODS Data obtained prospectively between January 2006 and December 2010 by a study colleague at our division of General Thoracic Surgery were retrospectively analysed. There were 491 patients who underwent thoracotomy. Eighty-one patients were excluded from the study due to incompatible data. Patients were divided into two groups according to the intercostal nerve state: Group I consisted of patients with ICNP and Group II consisted of patients with intercostal nerve sacrifice. RESULTS Group I consisted of 288 patients [206 male (71%), P < 0.001, mean age 66 years]. Group II consisted of 122 patients [79 male (64%), P = 0.001, mean age 66 years]. There was less use of opiate in Group I (P = 0.019). Early mobilization of the patients was significantly higher in Group I (P = 0.031). The rate of pneumonia and re-admission to the intensive care unit was higher in Group II (P = 0.017 and 0.023, respectively). The rate of pain-free patients at discharge was significantly higher in Group I (P = 0.028). A 2-week follow-up after hospital discharge showed parasternal hypoesthesia to be more in Group II (P = 0.034). Significant patient contentment in Group I was noticed (P = 0.014). Chronic post-thoracotomy pain (CPTP) was higher in Group II (P = 0.016). CONCLUSIONS ICNP without harvesting an intercostal muscle flap achieves excellent outcomes in controlling acute post-thoracotomy pain and CPTP. ICNP is an effective, simple method to perform, and it should be considered as standard in performing thoracotomy.
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How did Islam survive in the Soviet Union, and how did it develop since 1991? In four case studies and four longitudinal surveys, senior specialists from the area and two German junior scholars discuss the transformations of Islam in Tatarstan, Azerbaijan, Daghestan, Uzbekistan and Tajikistan. Several chapters analyze the Bolsheviks’ attack on Islam since the 1920s. Altay Göyüşov and Il’nur Minnullin demonstrate how the Soviets first attempted to draw some groups of Muslim scholars and intellectuals to their side, in Azerbaijan and Tatarstan, respectively. In the early 1930s collectivization and outright state terror made a complete end to the Islamic infrastructure, including mosques and pious foundations, Muslim village courts (as shown by Vladimir Bobrovnikov for Dagestan), Islamic educational institutions (as documented by Aširbek Muminov for Uzbekistan), as well as the Muslim press (analyzed by Dilyara Usmanova for Tatarstan); also Sufi brotherhoods became a main target of violent repression (Šamil‘ Šixaliev, for Dagestan). Repression was followed by the establishment of a modus vivendi between state and religion in the post-war period (Muminov, Bobrovnikov, Šixaliev), and by the instrumentalization of religion for patriotic purposes in the post-Soviet Caucasus and Central Asia (Christine Hunner-Kreisel, Manja Stephan, both based on fieldwork). By the early 2000s Islam was almost everywhere back under full state control; the leading role of the state for defining „good“ and „bad“ Islam is largely taken for granted. While similar forms of state pressure in all regions thus allow us to draw an overall picture of how Islamic traditions were repressed and reanimated, the „archival revolution“ of the early 1990s provides fascinating insights into the specific developments in the individual regions, and into the adaptation strategies of the Muslim scholars and intellectuals on the spot. Still, the Soviet heritage is still very palpable; also the attempts to leapfrog the Soviet period and to link up again with the individual local Islamic traditions from before 1917, and even the negation of the Soviet experience in the form of embracing Islamic trends from abroad, are often still couched in largely Soviet mental frameworks.
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Enterococcus faecalis is a Gram-positive bacterium that lives as a commensal organism in the mammalian gastrointestinal tract, but can behave as an opportunistic pathogen. Our lab discovered that mutation of the eutK gene attenuates virulence of E. faecalis in the C. elegans model host. eutK is part of the ethanolamine metabolic pathway which was previously unknown in E. faecalis. I discovered the presence of two unique posttranscriptional regulatory features that control expression of eut locus genes. The first feature I found is an AdoCBL riboswitch, a cis-acting RNA regulatory element that acts as a positive regulator of gene expression. The second feature I discovered is a unique two-component system, EutVW. The EutV response regulator contains an ANTAR family domain, which binds RNA to trigger transcriptional antitermination. I determined that induction of expression of several genes in the eut locus is dependent on ethanolamine, AdoCBL and the two-component system. AdoCBL and ethanolamine are both required for induction of eut locus gene expression. Additionally, I discovered eutG is regulated by a unique mechanism of antitermination. Both the AdoCBL riboswitch and EutV response regulator control the expression of the downstream gene eutG. EutV potentially acts through a novel antitermination mechanism in which a dimer of EutV binds to a pair of mRNA stem loops forming an antitermination complex. My data show a unique mechanism by which two environmental signals are integrated by two different posttranscriptional regulators to regulate a single locus.
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Development of transcriptional pulsing approaches using the c-fos and Tet-off promoter systems greatly facilitated studies of mRNA turnover in mammalian cells. However, optimal protocols for these approaches vary for different cell types and/or physiological conditions, limiting their widespread application. In this study, we have further optimized transcriptional pulsing systems for different cell lines and developed new protocols to facilitate investigation of various aspects of mRNA turnover. We apply the Tet-off transcriptional pulsing strategy to investigate ARE-mediated mRNA decay in human erythroleukemic K562 cells arrested at various phases of the cell cycle by pharmacological inhibitors. This application facilitates studies of the role of mRNA stability in control of cell-cycle dependent gene expression. To advance the investigation of factors involved in mRNA turnover and its regulation, we have also incorporated recently developed transfection and siRNA reagents into the transcriptional pulsing approach. Using these protocols, siRNA and DNA plasmids can be effectively cotransfected into mouse NIH3T3 cells to obtain high knockdown efficiency. Moreover, we have established a tTA-harboring stable line using human bronchial epithelial BEAS-2B cells and applied the transcriptional pulsing approach to monitor mRNA deadenylation and decay kinetics in this cell system. This broadens the application of the transcriptional pulsing system to investigate the regulation of mRNA turnover related to allergic inflammation. Critical factors that need to be considered when employing these approaches are characterized and discussed.
MOLECULAR MECHANISMS UNDERLYING THE TRANSCRIPTIONAL REGULATION OF T HELPER 17 AND REGULATORY T CELLS
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CD4+ T helper (Th) lymphocytes are vital for integrating immune responses by orchestrating the function of other immune cell types. Naïve Th cells can differentiate into different effector subsets that are characterized by their cytokine profile and immune regulatory functions. These subsets include Th1, Th2, Th17, natural and inducible regulatory T cells (nTreg and iTreg respectively), among others. We focused our investigation on two Th lineages, Th17 and regulatory T cells, with opposing functions in the immune system. These subsets have been suggested to be reciprocally regulated since they both require TGF-b for their development. We investigated the role of the Treg-associated master transcription factor Foxp3, and found that Foxp3 inhibits Th17 cell generation by preventing the transcriptional activity of the two main Th17-specific transcription factors, nuclear orphan receptors RORa and RORgt. At the molecular level, we identified two different functional domains in Foxp3 required for such inhibition: the LQALL sequence in exon 2 and the TIP60/HDAC7 binding domain. These domains could be crucial to either prevent the association of the nuclear receptors to coactivators or to recruit histone deacetylases to RORa- or RORgt-target genes. Since TGF-b is a common cytokine required for the commitment towards both Th lineages, we determined the role of the TGF-b-dependent signaling pathway in the generation of each subset. By using mice with deficiencies in signaling molecules downstream of TGF-b, we found that while Smad2, Smad3 and Smad4 are required for the generation of iTreg cells, only Smad2 is indispensable for the induction of IL-17-producing cells, suggesting that TGF-b induces these T helper lineages through differential signaling pathways. Thus, our findings describe novel transcriptional regulatory mechanisms that control the generation of two T helper lineages with opposing functions. These findings could provide novel therapeutic targets to treat diseases where the balance of these T cells is dysregulated, such as in autoimmunity, chronic infectious diseases and cancer.
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The expression of the chicken fast skeletal myosin alkali light chain (MLC) 3f is subject to complex patterns of control by developmental and physiologic signals. Regulation over MLC3f gene expression is thought to be exerted primarily at the transcriptional level. The purpose of this dissertation was to identify cis-acting elements on the 5$\sp\prime$ flanking region of chicken MLC3f gene that are important for transcriptional regulation. The results show that the 5$\sp\prime$ flanking region of MLC3f gene contains multiple cis-acting elements. The nucleotide sequence of these elements demonstrates a high degree of conservation between different species and are also found in the 5$\sp\prime$ flanking regions of many muscle protein genes. The first regulatory region is located between $-$185 and $-$150 bp from the transcription start site and contains an AT-rich element. Linker scanner analyses have revealed that this element has a positive effect on transcription of the MLC3f promoter. Furthermore, when linked to a heterologous viral promoter, it can enhance reporter gene expression in a muscle-specific manner, independent of distance or orientation.^ The second regulatory region is located between $-$96 and $-$64 from the transcription start site. Sequences downstream of $-$96 have the capacity to drive muscle-specific reporter gene expression, although the region between $-$96 and $-$64 has no intrinsic enhancer-like activity. Linker scanner analyses have identified a GC-rich motif that required efficient transcription of the MLC3f promoter. Mutations to this region of DNA results in diminished capacity to drive reporter gene expression and is correlated with disruption of the ability to bind sequence-specific transcription factors. These sequence-specific DNA-binding proteins were detected in both muscle and non-muscle extracts. The results suggest that the mere presence or absence of transcription factors cannot be solely responsible for regulation of MLC3f expression and that tissue-specific expression may arise from complex interactions with muscle-specific, as well as more ubiquitous transcription factors with multiple regulatory elements on the gene. ^
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The mammalian Cutl1 gene codes for the CCAAT displacement protein (CDP), which has been implicated as a transcriptional repressor in diverse processes such as terminal differentiation, cell cycle progression, and the control of nuclear matrix attachment regions. To investigate the in vivo function of Cutl1, we have replaced the C-terminal Cut repeat 3 and homeodomain exons with an in-frame lacZ gene by targeted mutagenesis in the mouse. The CDP-lacZ fusion protein is retained in the cytoplasm and fails to repress gene transcription, indicating that the Cutl1(lacZ) allele corresponds to a null mutation. Cutl1 mutant mice on inbred genetic backgrounds are born at Mendelian frequency, but die shortly after birth because of retarded differentiation of the lung epithelia, which indicates an essential role of CDP in lung maturation. A less pronounced delay in lung development allows Cutl1 mutant mice on an outbred background to survive beyond birth. These mice are growth-retarded and develop an abnormal pelage because of disrupted hair follicle morphogenesis. The inner root sheath (IRS) is reduced, and the transcription of Sonic hedgehog and IRS-specific genes is deregulated in Cutl1 mutant hair follicles, consistent with the specific expression of Cutl1 in the progenitors and cell lineages of the IRS. These data implicate CDP in cell-lineage specification during hair follicle morphogenesis, which resembles the role of the related Cut protein in specifying cell fates during Drosophila development.
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Bacillus anthracis plasmid pXO1 carries genes for three anthrax toxin proteins, pag (protective antigen), cya (edema factor), and lef (lethal factor). Expression of the toxin genes is enhanced by two signals: CO$\sb2$/bicarbonate and temperature. The CO$\sb2$/bicarbonate effect requires the presence of pXO1. I hypothesized that pXO1 harbors a trans-acting regulatory gene(s) required for CO$\sb2$/bicarbonate-enhanced expression of the toxin genes. Characterization of such a gene(s) will lead to increased understanding of the mechanisms by which B. anthracis senses and responds to host environments.^ A regulatory gene (atxA) on pXO1 was identified. Transcription of all three toxin genes is decreased in an atxA-null mutant. There are two transcriptional start sites for pag. Transcription from the major site, P1, is enhanced in elevated CO$\sb2$. Only P1 transcripts are significantly decreased in the atxA mutant. Deletion analysis of the pag upstream region indicates that the 111-bp region upstream of the P1 site is sufficient for atxA-mediated increase of this transcript. The cya and lef genes each have one apparent transcriptional start site. The cya and lef transcripts are significantly decreased in the atxA mutant. The atxA mutant is avirulent in mice. The antibody response to all three toxin proteins is significantly decreased in atxA mutant-infected mice. These data suggest that the atxA gene product activates expression of the toxin genes and is essential for virulence.^ Since expression of the toxin genes is dependent on atxA, whether increased toxin gene expression in response to CO$\sb2$/bicarbonate and temperature is associated with increased atxA expression was investigated. I monitored steady state levels of atxA mRNA and AtxA protein in different growth conditions. The results indicate that expression of atxA is not influenced by CO$\sb2$/bicarbonate. Steady state levels of atxA mRNA and AtxA protein are higher at 37$\sp\circ$C than 28$\sp\circ$C. However, increased pag expression at high temperature can not be attributed directly to increased atxA expression.^ There is evidence that an additional factor(s) may be involved in regulation of pag. Expression of pag in strains overproducing AtxA is significantly decreased compared to the wildtype strain. A specific interaction of tagged-AtxA with the pag upstream DNA has not been demonstrated. Furthermore, four proteins in B. anthracis extract can be co-immunoprecipitated with tagged-AtxA. Amino-terminal sequence of one protein has been determined and found highly homologous to chaperonins of GroEL family. Studies are under way to determine if this GroEL-like protein interactions with AtxA and plays any role in atxA-mediated activation of toxin genes. ^
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A series of ice cores from sites with different snow-accumulation rates across Law Dome, East Antarctica, was investigated for methanesulphonic acid (MSA) movement. The precipitation at these sites (up to 35 km apart) is influenced by the same air masses, the principal difference being the accumulation rate. At the low-accumulation-rate W20k site (0.17 in ice equivalent), MSA was completely relocated from the summer to winter layer. Moderate movement was observed at the intermediate-accumulation-rate site (0.7 in ice equivalent), Dome Summit South (DSS), while there was no evidence of movement at the high-accumulation-rate DE08 site (1.4 in ice equivalent). The main DSS record of MSA covered the epoch AD 1727-2000 and was used to investigate temporal post-depositional changes. Co-deposition of MSA and sea-salt ions was observed of the surface layers, outside of the main summer MSA peak, which complicates interpretation of these peaks as evidence of movement in deeper layers. A seasonal study of the 273 year DSS record revealed MSA migration predominantly from summer into autumn (in the up-core direction), but this migration was suppressed during the Tambora (1815) and unknown (1809) volcanic eruption period, and enhanced during an epoch (1770-1800) with high summer nitrate levels. A complex interaction between the gradients in nss-sulphate, nitrate and sea salts (which are influenced by accumulation rate) is believed to control the rate and extent of movement of MSA.
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BACKGROUND: The purpose of this study was to investigate the scale recalibration construct of response shift and its relationship to glycemic control in children with diabetes. METHODS: At year 1, thirty-eight children with type 1 diabetes attending a diabetes summer camp participated. At baseline and post-camp they completed the Problem Areas in Diabetes (PAID) questionnaire. Post-camp, the PAID was also completed using the 'thentest' method, which requires a retrospective judgment about their baseline functioning. At year 2, fifteen of the original participants reported their HbA1c. RESULTS: PAID scores significantly decreased from baseline to post-camp. An even larger difference was found between thentest and post-camp scores, suggesting scale recalibration. There was a significant positive correlation between year 1 HbA1c and thentest scores. Partial correlation analysis between PAID thentest scores and year 2 HbA1c, controlling for year 1 HbA1c, showed that higher PAID thentest scores were associated with higher year 2 HbA1c. CONCLUSION: Results from this small sample suggest that children with diabetes do show scale recalibration, and that it may be related to glycemic control.
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BACKGROUND To summarize the available evidence on the effectiveness of psychological interventions for patients with post-traumatic stress disorder (PTSD). METHOD We searched bibliographic databases and reference lists of relevant systematic reviews and meta-analyses for randomized controlled trials that compared specific psychological interventions for adults with PTSD symptoms either head-to-head or against control interventions using non-specific intervention components, or against wait-list control. Two investigators independently extracted the data and assessed trial characteristics. RESULTS The analyses included 4190 patients in 66 trials. An initial network meta-analysis showed large effect sizes (ESs) for all specific psychological interventions (ESs between -1.10 and -1.37) and moderate effects of psychological interventions that were used to control for non-specific intervention effects (ESs -0.58 and -0.62). ES differences between various types of specific psychological interventions were absent to small (ES differences between 0.00 and 0.27). Considerable between-trial heterogeneity occurred (τ 2 = 0.30). Stratified analyses revealed that trials that adhered to DSM-III/IV criteria for PTSD were associated with larger ESs. However, considerable heterogeneity remained. Heterogeneity was reduced in trials with adequate concealment of allocation and in large-sized trials. We found evidence for small-study bias. CONCLUSIONS Our findings show that patients with a formal diagnosis of PTSD and those with subclinical PTSD symptoms benefit from different psychological interventions. We did not identify any intervention that was consistently superior to other specific psychological interventions. However, the robustness of evidence varies considerably between different psychological interventions for PTSD, with most robust evidence for cognitive behavioral and exposure therapies.