Influência da porção extensora do músculo glúteo máximo sobre a inclinação da pelve antes e depois da realização de um protocolo de fadiga

INTRODUÇÃO: Há carência na literatura de dados que determinem qual a influência da porção extensora do músculo glúteo máximo na inclinação da pelve no plano sagital e, portanto, na estabilidade lombar. OBJETIVOS: Verificar a influência da porção extensora do músculo glúteo máximo sobre a inclinação da pelve. MÉTODOS: Foram recrutadas 10 voluntárias jovens, saudáveis, com índices de massa corpórea (IMC's) menores que 24,9 kg/m² e com dismetria real de membros inferiores (MMII) inferior a 1 cm. Foram avaliados o IMC, o perímetro pélvico e o comprimento dos MMII e, posteriormente, os graus de inclinação das hemipelves e a assimetria entre elas pela análise de uma fotografia em perfil ortostático usando o SAPO (Software para Avaliação Postural). Em seguida, a porção extensora do músculo glúteo máximo do lado dominante foi induzido à fadiga, após a qual foram determinadas novamente a inclinação das hemipelves e a assimetria entre elas. Testes de Pearson r e teste t de student foram realizados no nível de significância &#945;=0,05. RESULTADOS: Não houve correlação entre as variáveis de confusão e a assimetria dos ângulos das hemipelves. O ângulo da hemipelve apresentou modificação significativa do lado dominante (t=3,760; p=0,004). CONCLUSÕES: A fadiga da porção extensora do músculo glúteo máximo pode gerar um aumento do ângulo de inclinação da pelve homolateral.<br>INTRODUCTION: There is a lack of data in the literature for determining the influences of the extensor portion of the gluteus maximus muscle on pelvic tilting and, thus, on lumbar stability. OBJECTIVES: To assess the influences of the extensor portion of the gluteus maximus muscle on pelvic tilt. METHODS: Ten healthy young subjects were recruited, with a body mass index (BMI) below 24.9 kg/m² and leg length discrepancy below 1 cm. The BMI, pelvic perimeter and lower-limb lengths were assessed and, subsequently, the degrees of hemi-pelvic tilt and asymmetry between them were analyzed using lateral view photographs of the subjects in a standing position, using SAPO (Software for Postural Assessment). Next, fatigue was induced in the extensor portion of the gluteus maximus muscle on the dominant side, and after that the hemi-pelvic tilt and the asymmetry between the hemi-pelvises were reassessed. The Pearson r and Student t tests were conducted at the significance level of &#945;=0.05. RESULTS: There were no significant correlations between the confounding variables and asymmetry of the hemi-pelvic angles. There were significant changes in the hemi-pelvic angle of the dominant side (t=3.760; p=0.004). CONCLUSIONS: Fatigue in the extensor portion of the gluteus maximus muscle can generate increases in the tilt angle of the ipsilateral pelvis

Memory Acquisition and Retrieval Impact Different Epigenetic Processes that Regulate Gene Expression

Background: A fundamental question in neuroscience is how memories are stored and retrieved in the brain. Long-term memory formation requires transcription, translation and epigenetic processes that control gene expression. Thus, characterizing genome-wide the transcriptional changes that occur after memory acquisition and retrieval is of broad interest and importance. Genome-wide technologies are commonly used to interrogate transcriptional changes in discovery-based approaches. Their ability to increase scientific insight beyond traditional candidate gene approaches, however, is usually hindered by batch effects and other sources of unwanted variation, which are particularly hard to control in the study of brain and behavior. Results: We examined genome-wide gene expression after contextual conditioning in the mouse hippocampus, a brain region essential for learning and memory, at all the time-points in which inhibiting transcription has been shown to impair memory formation. We show that most of the variance in gene expression is not due to conditioning and that by removing unwanted variance through additional normalization we are able provide novel biological insights. In particular, we show that genes downregulated by memory acquisition and retrieval impact different functions: chromatin assembly and RNA processing, respectively. Levels of histone 2A variant H2AB are reduced only following acquisition, a finding we confirmed using quantitative proteomics. On the other hand, splicing factor Rbfox1 and NMDA receptor-dependent microRNA miR-219 are only downregulated after retrieval, accompanied by an increase in protein levels of miR-219 target CAMKIIγ. Conclusions: We provide a thorough characterization of coding and non-coding gene expression during long-term memory formation. We demonstrate that unwanted variance dominates the signal in transcriptional studies of learning and memory and introduce the removal of unwanted variance through normalization as a necessary step for the analysis of genome-wide transcriptional studies in the context of brain and behavior. We show for the first time that histone variants are downregulated after memory acquisition, and splicing factors and microRNAs after memory retrieval. Our results provide mechanistic insights into the molecular basis of cognition by highlighting the differential involvement of epigenetic mechanisms, such as histone variants and post-transcriptional RNA regulation, after acquisition and retrieval of memory

Influência da porção extensora do músculo glúteo máximo sobre a inclinação da pelve antes e depois da realização de um protocolo de fadiga

Introduction: There is a lack of data in the literature for determining the influences of the extensor portion of the gluteus maximus muscle on pelvic tilting and, thus, on lumbar stability. Objectives: To assess the influences of the extensor portion of the gluteus maximus muscle on pelvic tilt. Methods: Ten healthy young subjects were recruited, with a body mass index (BMI) below 24.9 kg/m2 and leg length discrepancy below 1 cm. The BMI, pelvic perimeter and lower-limb lengths were assessed and, subsequently, the degrees of hemi-pelvic tilt and asymmetry between them were analyzed using lateral view photographs of the subjects in a standing position, using SAPO (Software for Postural Assessment). Next, fatigue was induced in the extensor portion of the gluteus maximus muscle on the dominant side, and after that the hemi-pelvic tilt and the asymmetry between the hemi-pelvises were reassessed. The Pearson r and Student t tests were conducted at the significance level of α=0.05. Results: There were no significant correlations between the confounding variables and asymmetry of the hemi-pelvic angles. There were significant changes in the hemi-pelvic angle of the dominant side (t=3.760; p=0.004). Conclusions: Fatigue in the extensor portion of the gluteus maximus muscle can generate increases in the tilt angle of the ipsilateral pelvis.INTRODUÇÃO: Há carência na literatura de dados que determinem qual a influência da porção extensora do músculo glúteo máximo na inclinação da pelve no plano sagital e, portanto, na estabilidade lombar. OBJETIVOS: Verificar a influência da porção extensora do músculo glúteo máximo sobre a inclinação da pelve. MÉTODOS: Foram recrutadas 10 voluntárias jovens, saudáveis, com índices de massa corpórea (IMC's) menores que 24,9 kg/m2 e com dismetria real de membros inferiores (MMII) inferior a 1 cm. Foram avaliados o IMC, o perímetro pélvico e o comprimento dos MMII e, posteriormente, os graus de inclinação das hemipelves e a assimetria entre elas pela análise de uma fotografia em perfil ortostático usando o SAPO (Software para Avaliação Postural). Em seguida, a porção extensora do músculo glúteo máximo do lado dominante foi induzido à fadiga, após a qual foram determinadas novamente a inclinação das hemipelves e a assimetria entre elas. Testes de Pearson r e teste t de student foram realizados no nível de significância α=0,05. RESULTADOS: Não houve correlação entre as variáveis de confusão e a assimetria dos ângulos das hemipelves. O ângulo da hemipelve apresentou modificação significativa do lado dominante (t=3,760; p=0,004). CONCLUSÕES: A fadiga da porção extensora do músculo glúteo máximo pode gerar um aumento do ângulo de inclinação da pelve homolateral

BRCA2 polymorphic stop codon K3326X and the risk of breast, prostate, and ovarian cancers

Background: The K3326X variant in BRCA2 (BRCA2*c.9976A&gt;T; p.Lys3326*; rs11571833) has been found to be associated with small increased risks of breast cancer. However, it is not clear to what extent linkage disequilibrium with fully pathogenic mutations might account for this association. There is scant information about the effect of K3326X in other hormone-related cancers. Methods: Using weighted logistic regression, we analyzed data from the large iCOGS study including 76 637 cancer case patients and 83 796 control patients to estimate odds ratios (ORw) and 95% confidence intervals (CIs) for K3326X variant carriers in relation to breast, ovarian, and prostate cancer risks, with weights defined as probability of not having a pathogenic BRCA2 variant. Using Cox proportional hazards modeling, we also examined the associations of K3326X with breast and ovarian cancer risks among 7183 BRCA1 variant carriers. All statistical tests were two-sided. Results: The K3326X variant was associated with breast (ORw = 1.28, 95% CI = 1.17 to 1.40, P = 5.9x10- 6) and invasive ovarian cancer (ORw = 1.26, 95% CI = 1.10 to 1.43, P = 3.8x10-3). These associations were stronger for serous ovarian cancer and for estrogen receptor–negative breast cancer (ORw = 1.46, 95% CI = 1.2 to 1.70, P = 3.4x10-5 and ORw = 1.50, 95% CI = 1.28 to 1.76, P = 4.1x10-5, respectively). For BRCA1 mutation carriers, there was a statistically significant inverse association of the K3326X variant with risk of ovarian cancer (HR = 0.43, 95% CI = 0.22 to 0.84, P = .013) but no association with breast cancer. No association with prostate cancer was observed. Conclusions: Our study provides evidence that the K3326X variant is associated with risk of developing breast and ovarian cancers independent of other pathogenic variants in BRCA2. Further studies are needed to determine the biological mechanism of action responsible for these associations

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO

Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file

The Cryptosporidium parvum Kinome

<p>Abstract</p> <p>Background</p> <p>Hundreds of millions of people are infected with cryptosporidiosis annually, with immunocompromised individuals suffering debilitating symptoms and children in socioeconomically challenged regions at risk of repeated infections. There is currently no effective drug available. In order to facilitate the pursuit of anti-cryptosporidiosis targets and compounds, our study spans the classification of the <it>Cryptosporidium parvum </it>kinome and the structural and biochemical characterization of representatives from the CDPK family and a MAP kinase.</p> <p>Results</p> <p>The <it>C</it>. <it>parvum </it>kinome comprises over 70 members, some of which may be promising drug targets. These <it>C. parvum </it>protein kinases include members in the AGC, Atypical, CaMK, CK1, CMGC, and TKL groups; however, almost 35% could only be classified as OPK (other protein kinases). In addition, about 25% of the kinases identified did not have any known orthologues outside of <it>Cryptosporidium spp</it>. Comparison of specific kinases with their <it>Plasmodium falciparum </it>and <it>Toxoplasma gondii </it>orthologues revealed some distinct characteristics within the <it>C. parvum </it>kinome, including potential targets and opportunities for drug design. Structural and biochemical analysis of 4 representatives of the CaMK group and a MAP kinase confirms features that may be exploited in inhibitor design. Indeed, screening <it>Cp</it>CDPK1 against a library of kinase inhibitors yielded a set of the pyrazolopyrimidine derivatives (PP1-derivatives) with IC₅₀values of < 10 nM. The binding of a PP1-derivative is further described by an inhibitor-bound crystal structure of <it>Cp</it>CDPK1. In addition, structural analysis of <it>Cp</it>CDPK4 identified an unprecedented Zn-finger within the CDPK kinase domain that may have implications for its regulation.</p> <p>Conclusions</p> <p>Identification and comparison of the <it>C. parvum </it>protein kinases against other parasitic kinases shows how orthologue- and family-based research can be used to facilitate characterization of promising drug targets and the search for new drugs.</p