128 research outputs found
Pure spinor superfields -- an overview
Maximally supersymmetric theories do not allow off-shell superspace
formulations with traditional superfields containing a finite set of auxiliary
fields. It has become clear that off-shell supersymmetric action formulations
of such models can be achieved by the introduction of pure spinors. In this
talk, an overview of this formalism is given, with emphasis on D=10
super-Yang-Mills theory and D=11 supergravity. This a somewhat expanded version
of a talk presented at the workshop "Breaking of supersymmetry and ultraviolet
divergences in extended supergravity" (BUDS), Laboratori Nazionali di Frascati,
March 25-28, 2013.Comment: 34 pp., 2 figs., contributions to the proceedings of the workshop
"Breaking of supersymmetry and ultraviolet divergences in extended
supergravity" (BUDS), Laboratori Nazionali di Frascati, March 25-28, 201
The role of receptivity in the courtship behavior of Podocnemis erythrocephala in captivity
The courtship behavior of Podocnemis erythrocephala (Red-headed Amazon River Turtle) in captivity was studied to examine female receptivity and male response to female rejection. We observed 20 females and 39 males in 150 sessions (3β6Β h/day for a total of 450Β h). In 36% of the trials, there was no interaction between males and females, and 20% of the trials resulted in copulations. All males introduced into tanks approached females, and eventually there was aggression among the males. In 48% of the experiments, females also searched for or approached males. When males initially approached females, they either accepted the maleβs advances (14%), rejected the male passively (38%), or rejected the male aggressively (48%). In 86% of the cases where males were rejected, 4% attempted to approach females again, and in 51% they were ultimately successful
Identification of biomarkers for the antiangiogenic and antitumour activity of the superoxide dismutase 1 (SOD1) inhibitor tetrathiomolybdate (ATN-224)
Tetrathiomolybdate (choline salt; ATN-224), a specific, high-affinity copper binder, is currently being evaluated in several phase II cancer trials. ATN-224 inhibits CuZn superoxide dismutase 1 (SOD1) leading to antiangiogenic and antitumour effects. The pharmacodynamics of tetrathiomolybdate has been followed by tracking ceruloplasmin (Cp), a biomarker for systemic copper. However, at least in mice, the inhibition of angiogenesis occurs before a measurable decrease in systemic copper is observed. Thus, the identification and characterisation of other biomarkers to follow the activity of ATN-224 in the clinic is of great interest. Here, we present the preclinical evaluation of two potential biomarkers for the activity of ATN-224: (i) SOD activity measurements in blood cells in mice and (ii) levels of endothelial progenitor cells (EPCs) in bonnet macaques treated with ATN-224. The superoxide dismutase activity in blood cells in mice is rapidly inhibited by ATN-224 treatment at doses at which angiogenesis is maximally inhibited. Furthermore, ATN-224 dosing in bonnet macaques causes a profound and reversible decrease in EPCs without significant toxicity. Thus, both SOD activity measurements and levels of EPCs may be useful biomarkers of the antiangiogenic activity of ATN-224 to be used in its clinical development
O ensino das ciΓͺncias experimentais no liceu, em Portugal, na I RepΓΊblica (1910-1926)
O ensino das ciΓͺncias experimentais (ECE) em Portugal ficou, como pretendemos demonstrar, fortemente marcado pela instauração da RepΓΊblica, que comemorou no ano transacto o seu centenΓ‘rio. A RepΓΊblica de 1910 pretendeu reformar toda a mentalidade portuguesa, atravΓ©s do pilar base β a educação β pela qual seria capaz de sacudir a nossa maneira de ser, lanΓ§ando desta forma o paΓs para um progresso de nΓvel europeu. O estudo a que nos propomos, uma investigação documental no domΓnio da HistΓ³ria da CiΓͺncia1, visa aprofundar os conhecimentos existentes sobre esta Γ©poca e perceber o impacto da reforma do ECE, principalmente nos Liceus, caracterizando as principais figuras, polΓticas e docentes responsΓ‘veis pela sua conceptualização e aplicação. AtravΓ©s desta investigação procuraremos lanΓ§ar as primeiras bases para descobrir as origens deste pensamento, querendo ainda comparar os fundamentos psicopedagΓ³gicos, epistemolΓ³gicos e sociolΓ³gicos da Γ©poca com as principais ideias actualmente presentes no ensino da CiΓͺncia. Com este trabalho pretendemos, num primeiro momento, apresentar e divulgar o desenho da investigação e os seus objectivos, na procura de estabelecer parcerias e receber contributos da comunidade acadΓ©mica interessada por esta problemΓ‘tica
A chemically modified antibody mediates complete eradication of tumours by selective disruption of tumour blood vessels
These results reinforce the concept that vascular shutdown can induce a curative avalanche of tumour cell death. Immuno-photodynamic therapy may be particularly indicated for squamous cell carcinoma of the skin, which we show to be strongly positive for markers of angiogenesis
A multidisciplinary consensus on the morphological and functional responses to immunotherapy treatment
The implementation of immunotherapy has radically changed the treatment of oncological patients. Currently, immunotherapy is indicated in the treatment of patients with head and neck tumors, melanoma, lung cancer, bladder tumors, colon cancer, cervical cancer, breast cancer, Merkel cell carcinoma, liver cancer, leukemia and lymphomas. However, its efficacy is restricted to a limited number of cases. The challenge is, therefore, to identify which subset of patients would benefit from immunotherapy. To this end, the establishment of immunotherapy response criteria and predictive and prognostic biomarkers is of paramount interest. In this report, a group of experts of the Spanish Society of Medical Oncology (SEOM), the Spanish Society of Medical Radiology (SERAM), and Spanish Society of Nuclear Medicine and Molecular Imaging (SEMNIM) provide an up-to-date review and a consensus guide on these issues
Use of multidimensional item response theory methods for dementia prevalence prediction: an example using the Health and Retirement Survey and the Aging, Demographics, and Memory Study
Background: Data sparsity is a major limitation to estimating national and global dementia burden. Surveys with full diagnostic evaluations of dementia prevalence are prohibitively resource-intensive in many settings. However, validation samples from nationally representative surveys allow for the development of algorithms for the prediction of dementia prevalence nationally. Methods: Using cognitive testing data and data on functional limitations from Wave A (2001β2003) of the ADAMS study (n = 744) and the 2000 wave of the HRS study (n = 6358) we estimated a two-dimensional item response theory model to calculate cognition and function scores for all individuals over 70. Based on diagnostic information from the formal clinical adjudication in ADAMS, we fit a logistic regression model for the classification of dementia status using cognition and function scores and applied this algorithm to the full HRS sample to calculate dementia prevalence by age and sex. Results: Our algorithm had a cross-validated predictive accuracy of 88% (86β90), and an area under the curve of 0.97 (0.97β0.98) in ADAMS. Prevalence was higher in females than males and increased over age, with a prevalence of 4% (3β4) in individuals 70β79, 11% (9β12) in individuals 80β89Β years old, and 28% (22β35) in those 90 and older. Conclusions: Our model had similar or better accuracy as compared to previously reviewed algorithms for the prediction of dementia prevalence in HRS, while utilizing more flexible methods. These methods could be more easily generalized and utilized to estimate dementia prevalence in other national surveys
Global mortality from dementia: Application of a newmethod and results from the global burden of disease study 2019
INTRODUCTION:
Dementia is currently one of the leading causes of mortality globally, and mortality due to dementia will likely increase in the future along with corresponding increases in population growth and population aging. However, large inconsistencies in coding practices in vital registration systems over time and between countries complicate the estimation of global dementia mortality.
METHODS:
We meta-analyzed the excess risk of death in those with dementia and multiplied these estimates by the proportion of dementia deaths occurring in those with severe, end-stage disease to calculate the total number of deaths that could be attributed to dementia.
RESULTS:
We estimated that there were 1.62 million (95% uncertainty interval [UI]: 0.41β4.21) deaths globally due to dementia in 2019. More dementia deaths occurred in women (1.06 million [0.27β2.71]) than men (0.56 million [0.14β1.51]), largely but not entirely due to the higher life expectancy in women (age-standardized female-to-male ratio 1.19 [1.10β1.26]). Due to population aging, there was a large increase in all-age mortality rates from dementia between 1990 and 2019 (100.1% [89.1β117.5]). In 2019, deaths due to dementia ranked seventh globally in all ages and fourth among individuals 70 and older compared to deaths from other diseases estimated in the Global Burden of Disease (GBD) study.
DISCUSSION:
Mortality due to dementia represents a substantial global burden, and is expected to continue to grow into the future as an older, aging population expands globally
Angiogenesis in Differentiated Placental Multipotent Mesenchymal Stromal Cells Is Dependent on Integrin Ξ±5Ξ²1
Human placental multipotent mesenchymal stromal cells (hPMSCs) can be isolated from term placenta, but their angiogenic ability and the regulatory pathways involved are not known. hPMSCs were shown to express integrins Ξ±v, Ξ±4, Ξ±5, Ξ²1, Ξ²3, and Ξ²5 and could be induced to differentiate into cells expressing endothelial markers. Increases in cell surface integrins Ξ±5 and Ξ²1, but not Ξ±4, Ξ±vΞ²3, or Ξ±vΞ²5, accompanied endothelial differentiation. Vascular endothelial growth factor-A augmented the effect of fibronectin in enhancing adhesion and migration of differentiated hPMSC through integrin Ξ±5Ξ²1, but not Ξ±vΞ²3 or Ξ±vΞ²5. Formation of capillary-like structures in vitro from differentiated cells was inhibited by pre-treatment with function-blocking antibodies to integrins Ξ±5 and Ξ²1. When hPMSCs were seeded onto chick chorioallantoic membranes (CAM), human von Willebrand factor-positive cells were observed to engraft in the chick endothelium. CAMs transplanted with differentiated hPMSCs had a greater number of vessels containing human cells and more incorporated cells per vessel compared to CAMs transplanted with undifferentiated hPMSCs, and overall angiogenesis was enhanced more by the differentiated cells. Function-blocking antibodies to integrins Ξ±5 and Ξ²1 inhibited angiogenesis in the CAM assay. These results suggest that differentiated hPMSCs may contribute to blood vessel formation, and this activity depends on integrin Ξ±5Ξ²1
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