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"Wu, Megan A."
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Circulating tumor DNA reveals mechanisms of lorlatinib resistance in patients with relapsed/refractory ALK-driven neuroblastoma
2023
Activating point mutations in
Anaplastic Lymphoma Kinase (ALK
) have positioned
ALK
as the only mutated oncogene tractable for targeted therapy in neuroblastoma. Cells with these mutations respond to lorlatinib in pre-clinical studies, providing the rationale for a first-in-child Phase 1 trial (NCT03107988) in patients with ALK-driven neuroblastoma. To track evolutionary dynamics and heterogeneity of tumors, and to detect early emergence of lorlatinib resistance, we collected serial circulating tumor DNA samples from patients enrolled on this trial. Here we report the discovery of off-target resistance mutations in 11 patients (27%), predominantly in the RAS-MAPK pathway. We also identify newly acquired secondary compound
ALK
mutations in 6 (15%) patients, all acquired at disease progression. Functional cellular and biochemical assays and computational studies elucidate lorlatinib resistance mechanisms. Our results establish the clinical utility of serial circulating tumor DNA sampling to track response and progression and to discover acquired resistance mechanisms that can be leveraged to develop therapeutic strategies to overcome lorlatinib resistance.
Inhibition of ALK is initially effective in patients with ALK-driven lung cancer but resistance often arises. Here, the authors use circulating tumour DNA, collected as part of a phase I trial investigating lorlatinib (ALK inhibitor) in pediatric patients with ALK-driven neuroblastoma, to detect early resistance mechanisms.
Journal Article
Effectiveness of physical activity on patients with depression and Parkinson's disease: A systematic review
by
Wu, Pei-Ling
,
Lee, Megan
,
Huang, Tzu-Ting
in
Anxiety - complications
,
Anxiety - physiopathology
,
Balance
2017
In this paper we aimed to systematically review the literature on physical activity's effect on depressive symptoms in Parkinson disease.
Depression is a common symptom of Parkinson's disease and is associated with increased disability, rapid progression of motor symptoms, mortality, and adverse effects on Quality of Life.
A systematic review of primary research was undertaken and conducted according to the Preferred Reporting Items for Systematic Reviews.
Databases Scopus, Psycho-info, CINAHL, PubMed, and ProQuest Cochrance were searched from January 2006 to June 2017. The language was restricted to English.
Abstracts were screened and reviewed against the eligibility criteria (participants' mean age were ≥ 60 with PD, PA interventions, depression as one of outcome variables, and Randomized Control Trail or quasi-experimental design). Two reviewers appraised the quality of the data extracted. The modified Jadad scale assessed the quality of the methodology of the published papers.
The database search yielded 769 abstracts, 11 of which were included in this review and awarded scores ranging from 3 to 8 (Scale scores range from 0 to 8 points, higher scores indicated better quality) by the raters. These 11 studies included 342 patients and executed 17 kinds of physical activity programs. Results of this review show empirical evidence to support the efficacy of physical activity for the population with Parkinson's disease. Aerobic training exercise significantly improved the participants' scores on the Unified Parkinson's Disease Rating Scale, the Beck Depression Inventory, and the Quality of Life of the patients. Qigong improved scores in UPDRS-III and decreased incidences of multiple non-motor symptoms and depression. Furthermore, a balance-training program, such as Tai Chi, can improve postural stability and Quality of Life.
Physical activity may assuage the degeneration of motor skills and depression as well as increase the Quality of Life of Parkinson's disease patients, with aerobic training producing the best results. These findings suggest that physical activity, notably aerobic training, could be a good exercise strategy for patients with Parkinson's disease.
Journal Article
Efficacy, long-term toxicity, and mechanistic studies of gold nanorods photothermal therapy of cancer in xenograft mice
2017
Gold nanorods (AuNRs)-assisted plasmonic photothermal therapy (AuNRs-PPTT) is a promising strategy for combating cancer in which AuNRs absorb near-infrared light and convert it into heat, causing cell death mainly by apoptosis and/or necrosis. Developing a valid PPTT that induces cancer cell apoptosis and avoids necrosis in vivo and exploring its molecular mechanism of action is of great importance. Furthermore, assessment of the long-term fate of the AuNRs after treatment is critical for clinical use. We first optimized the size, surface modification [rifampicin (RF) conjugation], and concentration (2.5 nM) of AuNRs and the PPTT laser power (2 W/cm²) to achieve maximal induction of apoptosis. Second, we studied the potential mechanism of action of AuNRs-PPTT using quantitative proteomic analysis in mouse tumor tissues. Several death pathways were identified, mainly involving apoptosis and cell death by releasing neutrophil extracellular traps (NETs) (NETosis), which were more obvious upon PPTT using RF-conjugated AuNRs (AuNRs@RF) than with polyethylene glycol thiol-conjugated AuNRs. Cytochrome c and p53-related apoptosis mechanisms were identified as contributing to the enhanced effect of PPTT with AuNRs@RF. Furthermore, Pin1 and IL18-related signaling contributed to the observed perturbation of the NETosis pathway by PPTT with AuNRs@RF. Third, we report a 15-month toxicity study that showed no long-term toxicity of AuNRs in vivo. Together, these data demonstrate that our AuNRs-PPTT platform is effective and safe for cancer therapy in mouse models. These findings provide a strong framework for the translation of PPTT to the clinic.
Journal Article
Zanubrutinib or Ibrutinib in Relapsed or Refractory Chronic Lymphocytic Leukemia
by
Grosicki, Sebastian
,
Shadman, Mazyar
,
Robak, Tadeusz
in
Adverse events
,
Antineoplastic Agents
,
Antineoplastic Agents - adverse effects
2023
In this trial in patients with relapsed CLL, progression-free survival at 2 years was 78% with zanubrutinib and 66% with ibrutinib. Infections were common with both; cardiac events were less frequent with zanubrutinib.
Journal Article
Evaluation of transplacental transfer of mRNA vaccine products and functional antibodies during pregnancy and infancy
2022
Studies are needed to evaluate the safety and effectiveness of mRNA SARS-CoV-2 vaccination during pregnancy, and the levels of protection provided to their newborns through placental transfer of antibodies. Here, we evaluate the transplacental transfer of mRNA vaccine products and functional anti-SARS-CoV-2 antibodies during pregnancy and early infancy in a cohort of 20 individuals vaccinated during late pregnancy. We find no evidence of mRNA vaccine products in maternal blood, placenta tissue, or cord blood at delivery. However, we find time-dependent efficient transfer of IgG and neutralizing antibodies to the neonate that persists during early infancy. Additionally, using phage immunoprecipitation sequencing, we find a vaccine-specific signature of SARS-CoV-2 Spike protein epitope binding that is transplacentally transferred during pregnancy. Timing of vaccination during pregnancy is critical to ensure transplacental transfer of protective antibodies during early infancy.
Pregnant individuals are at higher risk of SARS-CoV-2-related morbidity and mortality, yet more studies are needed to evaluate safety and efficacy of vaccination during pregnancy, and also the level of protection provided to the newborn. Here, the authors evaluate transplacental transfer of mRNA vaccine products and functional SARS-CoV-2 antibodies during pregnancy and early infancy.
Journal Article
Pathogen blockade of TAK1 triggers caspase-8–dependent cleavage of gasdermin D and cell death
by
Best, Zachary
,
Lien, Egil
,
Wu, Hao
in
Animals
,
Apoptosis
,
Apoptosis Regulatory Proteins - metabolism
2018
The activation of certain pattern-recognition receptors by pathogen-associated molecular patterns results in the formation of inflammasome complexes. Inflammasome complexes can initiate both the maturation of inflammatory cytokines and pyroptotic cell death via the caspase-mediated cleavage of gasdermin D (GSDMD). As of now, the only known regulators of GSDMD in macrophages are caspase-1 and caspase-11. Orning et al. report an additional pathway controlling GSDMD processing. YopJ, an effector molecule produced by Yersinia (the causative agent of plague), inhibits TAK1–IκB kinase signaling. This, in turn, results in caspase-8–directed cleavage of GSDMD, pyroptosis, and the release of interleukin 1β (IL-1β) and IL-18. Thus, in the arms race between host and pathogen, the host recognizes signaling disturbances as pathogenic and counters with inflammation and cell death. Science , this issue p. 1064 Bacterial blockade of key host signaling pathways triggers pyroptosis and inflammation. Limited proteolysis of gasdermin D (GSDMD) generates an N-terminal pore-forming fragment that controls pyroptosis in macrophages. GSDMD is processed via inflammasome-activated caspase-1 or -11. It is currently unknown whether macrophage GSDMD can be processed by other mechanisms. Here, we describe an additional pathway controlling GSDMD processing. The inhibition of TAK1 or IκB kinase (IKK) by the Yersinia effector protein YopJ elicits RIPK1- and caspase-8–dependent cleavage of GSDMD, which subsequently results in cell death. GSDMD processing also contributes to the NLRP3 inflammasome–dependent release of interleukin-1β (IL-1β). Thus, caspase-8 acts as a regulator of GSDMD-driven cell death. Furthermore, this study establishes the importance of TAK1 and IKK activity in the control of GSDMD cleavage and cytotoxicity.
Journal Article
Photonic chip-based low-noise microwave oscillator
2024
Numerous modern technologies are reliant on the low-phase noise and exquisite timing stability of microwave signals. Substantial progress has been made in the field of microwave photonics, whereby low-noise microwave signals are generated by the down-conversion of ultrastable optical references using a frequency comb
1
–
3
. Such systems, however, are constructed with bulk or fibre optics and are difficult to further reduce in size and power consumption. In this work we address this challenge by leveraging advances in integrated photonics to demonstrate low-noise microwave generation via two-point optical frequency division
4
,
5
. Narrow-linewidth self-injection-locked integrated lasers
6
,
7
are stabilized to a miniature Fabry–Pérot cavity
8
, and the frequency gap between the lasers is divided with an efficient dark soliton frequency comb
9
. The stabilized output of the microcomb is photodetected to produce a microwave signal at 20 GHz with phase noise of −96 dBc Hz
−1
at 100 Hz offset frequency that decreases to −135 dBc Hz
−1
at 10 kHz offset—values that are unprecedented for an integrated photonic system. All photonic components can be heterogeneously integrated on a single chip, providing a significant advance for the application of photonics to high-precision navigation, communication and timing systems.
We leverage advances in integrated photonics to generate low-noise microwaves with an optical frequency division architecture that can be low power and chip integrated.
Journal Article
Breast cancers utilize hypoxic glycogen stores via PYGB, the brain isoform of glycogen phosphorylase, to promote metastatic phenotypes
by
Goo, Laura E.
,
Little, Andrew C.
,
Merajver, Sofia D.
in
Biology and Life Sciences
,
Brain
,
Breast cancer
2019
In breast cancer, tumor hypoxia has been linked to poor prognosis and increased metastasis. Hypoxia activates transcriptional programs in cancer cells that lead to increased motility and invasion, as well as various metabolic changes. One of these metabolic changes, an increase in glycogen metabolism, has been further associated with protection from reactive oxygen species damage that may lead to premature senescence. Here we report that breast cancer cells significantly increase glycogen stores in response to hypoxia. We found that knockdown of the brain isoform of an enzyme that catalyzes glycogen breakdown, glycogen phosphorylase B (PYGB), but not the liver isoform, PYGL, inhibited glycogen utilization in estrogen receptor negative and positive breast cancer cells; whereas both independently inhibited glycogen utilization in the normal-like breast epithelial cell line MCF-10A. Functionally, PYGB knockdown and the resulting inhibition of glycogen utilization resulted in significantly decreased wound-healing capability in MCF-7 cells and a decrease in invasive potential of MDA-MB-231 cells. Thus, we identify PYGB as a novel metabolic target with potential applications in the management and/or prevention of metastasis in breast cancer.
Journal Article
Self-mixing in microtubule-kinesin active fluid from nonuniform to uniform distribution of activity
2022
Active fluids have applications in micromixing, but little is known about the mixing kinematics of systems with spatiotemporally-varying activity. To investigate, UV-activated caged ATP is used to activate controlled regions of microtubule-kinesin active fluid and the mixing process is observed with fluorescent tracers and molecular dyes. At low Péclet numbers (diffusive transport), the active-inactive interface progresses toward the inactive area in a diffusion-like manner that is described by a simple model combining diffusion with Michaelis-Menten kinetics. At high Péclet numbers (convective transport), the active-inactive interface progresses in a superdiffusion-like manner that is qualitatively captured by an active-fluid hydrodynamic model coupled to ATP transport. Results show that active fluid mixing involves complex coupling between distribution of active stress and active transport of ATP and reduces mixing time for suspended components with decreased impact of initial component distribution. This work will inform application of active fluids to promote micromixing in microfluidic devices.
Active fluids that consume local fuels to generate movements can be utilized to promote mixing in microfluidic devices. Here, Bate et al. show a transition from diffusion-like to superdiffusion-like behaviours with mixing efficacy depending on the Péclet number and spatial distribution of activities.
Journal Article
The gene cortex controls mimicry and crypsis in butterflies and moths
2016
The wing patterns of butterflies and moths (Lepidoptera) are diverse and striking examples of evolutionary diversification by natural selection. Lepidopteran wing colour patterns are a key innovation, consisting of arrays of coloured scales. We still lack a general understanding of how these patterns are controlled and whether this control shows any commonality across the 160,000 moth and 17,000 butterfly species. Here, we use fine-scale mapping with population genomics and gene expression analyses to identify a gene, cortex, that regulates pattern switches in multiple species across the mimetic radiation in Heliconius butterflies. cortex belongs to a fast-evolving subfamily of the otherwise highly conserved fizzy family of cell-cycle regulators, suggesting that it probably regulates pigmentation patterning by regulating scale cell development. In parallel with findings in the peppered moth (Biston betularia), our results suggest that this mechanism is common within Lepidoptera and that cortex has become a major target for natural selection acting on colour and pattern variation in this group of insects.
Journal Article