806 research outputs found
Unlocking the potential of anti-CD33 therapy in adult and childhood acute myeloid leukaemia
Acute Myeloid Leukaemia (AML) develops when there is a block in differentiation and uncontrolled proliferation of myeloid precursors, resulting in bone marrow failure. AML is a heterogeneous disease clinically, morphologically, and genetically, and biological differences between adult and childhood AML have been identified. AML comprises 15-20% of all children
less than fifteen years diagnosed with acute leukaemia. Relapse occurs in up to 40% of children with AML and is the commonest cause of death.1,2 Relapse arises from leukaemic stem cells (LSCs) that persist after conventional chemotherapy. The treatment of AML is challenging and new strategies to target LSCs are required. The cell surface marker CD33 has been identified as a
therapeutic target, and novel anti-CD33 immunotherapies are promising new agents in the treatment of AML. This review will summarise recent developments emphasising the genetic differences in adult and childhood AML, while highlighting the rationale for CD33 as a target for therapy, in all age groups
Study protocol for a randomised controlled trial evaluating the effect of prenatal omega-3 LCPUFA supplementation to reduce the incidence of preterm birth: The ORIP trial
Introduction: Preterm birth accounts for more than 85% of all perinatal complications and deaths. Seventy-five per cent of early preterm births (EPTBs) occur spontaneously and without identifiable risk factors. The need for a broadly applicable, effective strategy for primary prevention is paramount. Secondary outcomes from the docosahexaenoic acid (DHA) to Optimise Mother Infant Outcome trial showed that maternal supplementation until delivery with omega-3 (ω-3) long chain polyunsaturated fatty acid (LCPUFA), predominantly as DHA, resulted in a 50% reduction in the incidence of EPTB and an increase in the incidence of post-term induction or post-term prelabour caesarean section due to extended gestation. We aim to determine the effectiveness of supplementing the maternal diet with ω-3 LCPUFA until 34 weeks’ gestation on the incidence of EPTB.
Methods and analysis: This is a multicentre, parallel group, randomised, blinded and controlled trial. Women less than 20 weeks’ gestation with a singleton or multiple pregnancy and able to give informed consent are eligible to participate. Women will be randomised to receive high DHA fish oil capsules or control capsules without DHA. Capsules will be taken from enrolment until 34 weeks’ gestation. The primary outcome is the incidence of EPTB, defined as delivery before 34 completed weeks’ gestation. Key secondary outcomes include length of gestation, incidence of post-term induction or prelabour caesarean section and spontaneous EPTB. The target sample size is 5540 women (2770 per group), which will provide 85% power to detect an absolute reduction in the incidence of preterm birth of 1.16% (from 2.45% to 1.29%) between the DHA and control group (two sided α=0.05). The primary analysis will be based on the intention-to-treat principle.
Trial registration number: Australia and New Zealand Clinical Trial Registry Number: 2613001142729; Pre-results
Labeless and reversible immunosensor assay based upon an electrochemical current-transient protocol
A novel labeless and reversible immunoassay based upon an electrochemical
current-transient protocol is reported which offers many advantages in
comparison to classical immuno-biochemical analyses in terms of simplicity,
speed of response, reusability and possibility of multiple determinations.
Conducting polypyrrole films containing antibodies against 1) Bovine Serum
Albumin (BSA) and 2) Digoxin were deposited on the surface of platinum
electrodes to produce conductive affinity matrices having clearly defined
binding characteristics. The deposition process has been investigated using 125I
labelled anti-digoxin to determine optimal fabrication protocols. Antibody
integrity and activity, together with non-specific binding of antigen on the
conducting matrix have also been investigated using tritiated digoxin to probe
polypyrrole/anti-digoxin films. Amperometric responses to digoxin were recorded
in flow conditions using these films, but the technique was limited in use
mainly due to baseline instability. Anti-BSA - polypyrrole matrices were
investigated in more detail in both flow and quiescent conditions. No observable
response was found in flow conditions, however under quiescent conditions (in
non-stirred batch cell), anti-BSA – polypyrrole films have been demonstrated to
function as novel quantitative chronoamperometric immuno-biosensors when
interrogated using a pulsed potential waveform. The behaviour of the electrodes
showed that the antibody/antigen binding and/or interaction process underlying
the response observed was reversible in nature, indicating that the electrodes
could be used for multiple sensing protocols. Calibration profiles for BSA
demonstrated linearity for a concentration range of 0-50 ppm but tended towards
a plateau at higher concentrations. Factors relating to replicate sensor
production, sample measurement and reproducibility are discuss
Diminished Adolescent Social Well-Being During the COVID-19 Pandemic
Managing the COVID-19 pandemic involved implementing public health policies that disrupted students\u27 lives, creating conditions that substantially influenced their mental health and well-being. Subsequently, research focused don the mental health sequelae of increased depression and anxiety, but the possible impacts on adolescents\u27 social well-being have been largely unexamined. Social well-being is essential to youth\u27s overall mental health and can be diminished even without symptoms of depression and anxiety. This report explored heterogeneities in changes in adolescents\u27 social well-being from pre-COVID-19 to post-restrictions using longitudinal data from adolescents attending middle and high schools in California (N = 1,299; 49.9% female). Data collection involved four observations. Participants completed a school-based mental health wellness survey annually from 2019 to 2022. A latent profile analysis identified five profiles demonstrating distinctive social well-being trajectories. Two ordered profiles included Stable-High (28%) and Stable-Low (26%) patterns. Three groups represented nonordered profiles labeled as Succumbing (20%), Languishing (14%), and Recovering (12%). Pervasive decreases in social well-being were observed, and a significant portion of the adolescents did not recover to their pre-COVID-19 level by 2022. Adolescents in the Stable-High and Recovering profiles showed better psychological well-being, optimism, and school connectedness and less distress than their counterparts in the other three profiles. Mental health professionals should be aware of the pandemic\u27s effects on adolescents\u27 social well-being. Lower levels of social well-being may be a risk factor for adolescents developing generally jaded attitudes about their social networks and diminishing their potential engagement with sources of social support
Generic 3D Representation via Pose Estimation and Matching
Though a large body of computer vision research has investigated developing
generic semantic representations, efforts towards developing a similar
representation for 3D has been limited. In this paper, we learn a generic 3D
representation through solving a set of foundational proxy 3D tasks:
object-centric camera pose estimation and wide baseline feature matching. Our
method is based upon the premise that by providing supervision over a set of
carefully selected foundational tasks, generalization to novel tasks and
abstraction capabilities can be achieved. We empirically show that the internal
representation of a multi-task ConvNet trained to solve the above core problems
generalizes to novel 3D tasks (e.g., scene layout estimation, object pose
estimation, surface normal estimation) without the need for fine-tuning and
shows traits of abstraction abilities (e.g., cross-modality pose estimation).
In the context of the core supervised tasks, we demonstrate our representation
achieves state-of-the-art wide baseline feature matching results without
requiring apriori rectification (unlike SIFT and the majority of learned
features). We also show 6DOF camera pose estimation given a pair local image
patches. The accuracy of both supervised tasks come comparable to humans.
Finally, we contribute a large-scale dataset composed of object-centric street
view scenes along with point correspondences and camera pose information, and
conclude with a discussion on the learned representation and open research
questions.Comment: Published in ECCV16. See the project website
http://3drepresentation.stanford.edu/ and dataset website
https://github.com/amir32002/3D_Street_Vie
A novel method to allow noninvasive, longitudinal imaging of the murine immune system in vivo
In vivo imaging has revolutionized understanding of the spatiotemporal complexity that subserves the generation of successful effector and regulatory immune responses. Until now, invasive surgery has been required for microscopic access to lymph nodes (LNs), making repeated imaging of the same animal impractical and potentially affecting lymphocyte behavior. To allow longitudinal in vivo imaging, we conceived the novel approach of transplanting LNs into
the mouse ear pinna. Transplanted LNs maintain the structural and cellular organization of conventional secondary lymphoid organs. They participate in lymphocyte
recirculation and exhibit the capacity to receive and respond to local antigenic challenge. The same LN could be repeatedly imaged through time without the requirement for surgical exposure, and the dynamic behavior of the cells within the transplanted LN could be characterized. Crucially, the use of blood vessels as fiducial markers also allowed precise re-registration of the same regions for
longitudinal imaging. Thus, we provide the first demonstration of a method for repeated, noninvasive, in vivo imaging of lymphocyte behavior
The Sloan Digital Sky Survey Reverberation Mapping Project: Rapid CIV Broad Absorption Line Variability
We report the discovery of rapid variations of a high-velocity CIV broad
absorption line trough in the quasar SDSS J141007.74+541203.3. This object was
intensively observed in 2014 as a part of the Sloan Digital Sky Survey
Reverberation Mapping Project, during which 32 epochs of spectroscopy were
obtained with the Baryon Oscillation Spectroscopic Survey spectrograph. We
observe significant (>4sigma) variability in the equivalent width of the broad
(~4000 km/s wide) CIV trough on rest-frame timescales as short as 1.20 days
(~29 hours), the shortest broad absorption line variability timescale yet
reported. The equivalent width varied by ~10% on these short timescales, and by
about a factor of two over the duration of the campaign. We evaluate several
potential causes of the variability, concluding that the most likely cause is a
rapid response to changes in the incident ionizing continuum. If the outflow is
at a radius where the recombination rate is higher than the ionization rate,
the timescale of variability places a lower limit on the density of the
absorbing gas of n_e > 3.9 x 10^5 cm^-3. The broad absorption line variability
characteristics of this quasar are consistent with those observed in previous
studies of quasars, indicating that such short-term variability may in fact be
common and thus can be used to learn about outflow characteristics and
contributions to quasar/host-galaxy feedback scenarios.Comment: 15 pages, 14 figures. Accepted for publication in the Astrophysical
Journa
Multiple Perspectives on Implementing Inter-University Computer Conferencing
The purpose of this symposium is to discuss the organization, design, implementation and preliminary evaluation of an inter-university collaborative learning experience that used computer mediated communication (CMC) to link graduate students in several universities to discuss issues related to distance education. The discussion is based on the Globaled project, a computer conference that was set up and implemented for the second time, during the Fall 1993 semester. Globaled was first implemented during the Spring of 1992. With the increasing offering of distance education as a graduate discipline in many traditional universities, Globaled, can be seen as a unique way to connect graduate students across States and countries to participate in discussions related to the field of distance education
The Gene Ontology of eukaryotic cilia and flagella.
BACKGROUND:
Recent research into ciliary structure and function provides important insights into inherited diseases termed ciliopathies and other cilia-related disorders. This wealth of knowledge needs to be translated into a computational representation to be fully exploitable by the research community. To this end, members of the Gene Ontology (GO) and SYSCILIA Consortia have worked together to improve representation of ciliary substructures and processes in GO.
METHODS:
Members of the SYSCILIA and Gene Ontology Consortia suggested additions and changes to GO, to reflect new knowledge in the field. The project initially aimed to improve coverage of ciliary parts, and was then broadened to cilia-related biological processes. Discussions were documented in a public tracker. We engaged the broader cilia community via direct consultation and by referring to the literature. Ontology updates were implemented via ontology editing tools.
RESULTS:
So far, we have created or modified 127 GO terms representing parts and processes related to eukaryotic cilia/flagella or prokaryotic flagella. A growing number of biological pathways are known to involve cilia, and we continue to incorporate this knowledge in GO. The resulting expansion in GO allows more precise representation of experimentally derived knowledge, and SYSCILIA and GO biocurators have created 199 annotations to 50 human ciliary proteins. The revised ontology was also used to curate mouse proteins in a collaborative project. The revised GO and annotations, used in comparative 'before and after' analyses of representative ciliary datasets, improve enrichment results significantly.
CONCLUSIONS:
Our work has resulted in a broader and deeper coverage of ciliary composition and function. These improvements in ontology and protein annotation will benefit all users of GO enrichment analysis tools, as well as the ciliary research community, in areas ranging from microscopy image annotation to interpretation of high-throughput studies. We welcome feedback to further enhance the representation of cilia biology in GO
Colon carcinoma cells harboring PIK3CA mutations display resistance to growth factor deprivation induced apoptosis.
PIK3CA, encoding the p110alpha catalytic subunit of phosphatidylinositol 3-kinase (PI3K), is mutated in a variety of human cancers. We screened the colon cancer cell lines previously established in our laboratory for PIK3CA mutations and found that four of them harbored gain of function mutations. We have now compared a panel of mutant and wild-type cell lines for cell proliferation and survival in response to stress. There was little difference in PI3K activity between mutant PIK3CA-bearing cells (mutant cells) and wild-type PIK3CA-bearing cells (wild-type cells) under optimal growth conditions. However, the mutant cells showed constitutive PI3K activity during growth factor deprivation stress (GFDS), whereas PI3K activity decayed rapidly in the wild-type cells. Importantly, constitutively active PI3K rendered the mutant cells resistant to GFDS-induced apoptosis relative to the wild-type cells, indicating a biological advantage under stress conditions that is imparted by the mutant enzymes. Compared with the wild-type cells, the mutant cells were hypersensitive to the apoptosis induced by the PI3K inhibitor LY294002. In addition, PIK3CA small interfering RNA significantly decreased DNA synthesis and/or induced apoptosis in the mutant cells but not in the wild-type cells. Furthermore, ecotopic expression of a mutant PIK3CA in a nontumorigenic PIK3CA wild-type cell line resulted in resistance to GFDS-induced apoptosis, whereas transfection of wild-type PIK3CA or empty vector had little effect. Taken together, our studies show that mutant PIK3CA increases the capacity for proliferation and survival under environmental stresses, such as GFDS while also imparting greater dependency on the PI3K pathway for proliferation and survival
- …