5,367 research outputs found
How does cannabidiol (CBD) influence the acute effects of delta-9-tetrahydrocannabinol (THC) in humans? A systematic review
The recent liberalisation of cannabis regulation has increased public and scientific debate about its potential benefits and risks. A key focus has been the extent to which cannabidiol (CBD) might influence the acute effects of delta-9-tetrahydrocannabinol (THC), but this has never been reviewed systematically. In this systematic review of how CBD influences the acute effects of THC we identified 16 studies involving 466 participants. Ten studies were judged at low risk of bias. The findings were mixed, although CBD was found to reduce the effects of THC in several studies. Some studies found that CBD reduced intense experiences of anxiety or psychosis-like effects of THC and blunted some of the impairments on emotion and reward processing. However, CBD did not consistently influence the effects of THC across all studies and outcomes. There was considerable heterogeneity in dose, route of administration and THC:CBD ratio across studies and no clear dose-response profile emerged. Although findings were mixed, this review suggests that CBD may interact with some acute effects of THC
Detecção de doença residual mĂnima em crianças com leucemia linfoblĂĄstica aguda por citometria de fluxo
The detection of minimal residual disease (MRD) is an important prognostic factor in childhood acute lymphoblastic leukemia (ALL) providing crucial information on the response to treatment and risk of relapse. However, the high cost of these techniques restricts their use in countries with limited resources. Thus, we prospectively studied the use of flow cytometry (FC) with a simplified 3-color assay and a limited antibody panel to detect MRD in the bone marrow (BM) and peripheral blood (PB) of children with ALL. BM and PB samples from 40 children with ALL were analyzed on days (d) 14 and 28 during induction and in weeks 24-30 of maintenance therapy. Detectable MRD was defined as > 0.01% cells expressing the aberrant immunophenotype as characterized at diagnosis among total events in the sample. A total of 87% of the patients had an aberrant immunophenotype at diagnosis. On d14, 56% of the BM and 43% of the PB samples had detectable MRD. On d28, this decreased to 45% and 31%, respectively. The percentage of cells with the aberrant phenotype was similar in both BM and PB in T-ALL but about 10 times higher in the BM of patients with B-cell-precursor ALL. Moreover, MRD was detected in the BM of patients in complete morphological remission (44% on d14 and 39% on d28). MRD was not significantly associated to gender, age, initial white blood cell count or cell lineage. This FC assay is feasible, affordable and readily applicable to detect MRD in centers with limited resources.A detecção de doença residual mĂnima (DRM) ĂŠ um importante fator prognĂłstico na leucemia linfĂłide aguda (LLA) infantil e fornece informaçþes sobre a resposta ao tratamento e o risco de recaĂda. Entretanto, os altos custos das tĂŠcnicas utilizadas limitam seu uso nos paĂses em desenvolvimento. Desta forma, realizamos um estudo prospectivo para avaliar a citometria de fluxo (CF), utilizando trĂŞs fluorescĂŞncias e um painel limitado de anticorpos monoclonais, como mĂŠtodo de detecção de DRM em medula Ăłssea (MO) e sangue perifĂŠrico (SP) de crianças com LLA. Amostras de MO e SP de 40 crianças portadoras de LLA foram analisadas nos dias (d)14 e d28 da indução e nas semanas 24-30 da terapia de manutenção. Foram consideradas como DRM+ as amostras que apresentaram > 0,01% das cĂŠlulas com o fenĂłtipo aberrante (FA). Oitenta e sete por cento dos pacientes apresentaram FA ao diagnĂłstico. No d14, 56% das amostras de MO e 43% do SP apresentaram DRM. No d28, foi detectada DRM em 45% e 31% das amostras de MO e SP, respectivamente. A porcentagem de DRM na MO foi similar Ă do SP nos casos de LLA-T, mas aproximadamente dez vezes maior na LLA de precursor-B. Foi detectada DRM na MO de 44% e 39% dos pacientes que estavam remissĂŁo morfolĂłgica nos d14 e d28, respectivamente. NĂŁo foi demonstrada associação significante entre a presença de DRM e sexo, idade, leucometria inicial e linhagem celular. Esta tĂŠcnica de detecção de DRM por CF ĂŠ relativamente barata e pode ser aplicada em centros com recursos limitados
Spin, charge and orbital ordering in ferrimagnetic insulator YBaMnO
The oxygen-deficient (double) perovskite YBaMnO, containing
corner-linked MnO square pyramids, is found to exhibit ferrimagnetic
ordering in its ground state. In the present work we report
generalized-gradient-corrected, relativistic first-principles full-potential
density-functional calculations performed on YBaMnO in the nonmagnetic,
ferromagnetic and ferrimagnetic states. The charge, orbital and spin orderings
are explained with site-, angular momentum- and orbital-projected density of
states, charge-density plots, electronic structure and total energy studies.
YBaMnO is found to stabilize in a G-type ferrimagnetic state in
accordance with experimental results. The experimentally observed insulating
behavior appears only when we include ferrimagnetic ordering in our
calculation. We observed significant optical anisotropy in this material
originating from the combined effect of ferrimagnetic ordering and crystal
field splitting. In order to gain knowledge about the presence of different
valence states for Mn in YBaMnO we have calculated -edge x-ray
absorption near-edge spectra for the Mn and O atoms. The presence of the
different valence states for Mn is clearly established from the x-ray
absorption near-edge spectra, hyperfine field parameters and the magnetic
properties study. Among the experimentally proposed structures, the recently
reported description based on 4/ is found to represent the stable
structure
Urgent cardiac surgery in octogenarians
BACKGROUND: Urgent or emergent cardiac surgery in the elderly is burdened by high operative mortality and unacceptable postoperative quality of life. METHODS: From 1998 to 2007, 251 patients aged 80 years underwent nonelective cardiac surgery for urgent (n = 229) or emergent (n = 22) indications. A logistic regression to identify incremental risk factors for postoperative death was performed. RESULTS: The overall early mortality was of 12%, with 8% in urgent and 45% in emergent cases. The most frequent causes of death were infections, particularly pneumonia (23%), renal failure (20%), CVA (17%), respiratory failure (10%), and multisystem organ failure (10%). Incremental risk factors for early mortality were age, emergent procedure, aortic procedure, cardiopulmonary bypass time, and the presence of a major postoperative complication. Mean follow-up time was 5.4 +/- 3.2 years. CONCLUSIONS: An urgent cardiac surgery can be performed in octogenarians with acceptable operative mortality and good long-term survival
Genetic history of Calabrian Greeks reveals ancient events and long term isolation in the Aspromonte area of Southern Italy
Calabrian Greeks are an enigmatic population that have preserved and evolved a unique variety of language, Greco, survived in the isolated Aspromonte mountain area of Southern Italy. To understand their genetic ancestry and explore possible effects of geographic and cultural isolation, we genome-wide genotyped a large set of South Italian samples including both communities that still speak Greco nowadays and those that lost the use of this language earlier in time. Comparisons with modern and ancient populations highlighted ancient, long-lasting genetic links with Eastern Mediterranean and Caucasian/Near-Eastern groups as ancestral sources of Southern Italians. Our results suggest that the Aspromonte communities might be interpreted as genetically drifted remnants that departed from such ancient genetic background as a consequence of long-term isolation. Specific patterns of population structuring and higher levels of genetic drift were indeed observed in these populations, reflecting geographic isolation amplified by cultural differences in the groups that still conserve the Greco language. Isolation and drift also affected the current genetic differentiation at specific gene pathways, prompting for future genome-wide association studies aimed at exploring trait-related loci that have drifted up in frequency in these isolated groups
ATP Release from Dying Autophagic Cells and Their Phagocytosis Are Crucial for Inflammasome Activation in Macrophages
Pathogen-activated and damage-associated molecular patterns activate the inflammasome in macrophages. We report that mouse macrophages release IL-1β while co-incubated with pro-B (Ba/F3) cells dying, as a result of IL-3 withdrawal, by apoptosis with autophagy, but not when they are co-incubated with living, apoptotic, necrotic or necrostatin-1 treated cells. NALP3-deficient macrophages display reduced IL-1β secretion, which is also inhibited in macrophages deficient in caspase-1 or pre-treated with its inhibitor. This finding demonstrates that the inflammasome is activated during phagocytosis of dying autophagic cells. We show that activation of NALP3 depends on phagocytosis of dying cells, ATP release through pannexin-1 channels of dying autophagic cells, P2X7 purinergic receptor activation, and on consequent potassium efflux. Dying autophagic Ba/F3 cells injected intraperitoneally in mice recruit neutrophils and thereby induce acute inflammation. These findings demonstrate that NALP3 performs key upstream functions in inflammasome activation in mouse macrophages engulfing dying autophagic cells, and that these functions lead to pro-inflammatory responses
All-electron magnetic response with pseudopotentials: NMR chemical shifts
A theory for the ab initio calculation of all-electron NMR chemical shifts in
insulators using pseudopotentials is presented. It is formulated for both
finite and infinitely periodic systems and is based on an extension to the
Projector Augmented Wave approach of Bloechl [P. E. Bloechl, Phys. Rev. B 50,
17953 (1994)] and the method of Mauri et al [F. Mauri, B.G. Pfrommer, and S.G.
Louie, Phys. Rev. Lett. 77, 5300 (1996)]. The theory is successfully validated
for molecules by comparison with a selection of quantum chemical results, and
in periodic systems by comparison with plane-wave all-electron results for
diamond.Comment: 25 pages, 4 tables, submitted to Physical Review
Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV
A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay
channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7
TeV is presented. The data were collected at the LHC, with the CMS detector,
and correspond to an integrated luminosity of 4.6 inverse femtobarns. No
significant excess is observed above the background expectation, and upper
limits are set on the Higgs boson production cross section. The presence of the
standard model Higgs boson with a mass in the 270-440 GeV range is excluded at
95% confidence level.Comment: Submitted to JHE
- âŚ