330 research outputs found
MiR203 Mediates Subversion of Stem Cell Properties During Mammary Epithelial Differentiation via Repression of ΔNP63α and Promotes Mesenchymal-to-Epithelial Transition
During reproductive life, the mammary epithelium undergoes consecutive cycles of proliferation, differentiation and apoptosis. Doing so relies on the retained proliferative capacity, prolonged lifespan and developmental potency of mammary stem cells (MaSCs). ΔNp63α, the predominant TP63 isoform in mammary epithelia, is robustly expressed in MaSCs and is required for preservation of self-renewing capacity in diverse epithelial structures. However, the mechanism(s) underlying subversion of this activity during forfeiture of self-renewing capacity are poorly understood. MicroRNAs (miRNAs) govern critical cellular functions including stem cell maintenance, development, cell cycle regulation and differentiation by disrupting translation of target mRNAs. Data presented here indicate that expression of miR203, a miRNA that targets ΔNp63α and ΔNp63β is activated during luminal epithelial differentiation and that this pattern is observed in the murine mammary hierarchy. In addition, we present evidence that the transcription factor Zeb1 represses miR203 expression, thus enhancing ΔNp63α protein levels. Furthermore, ectopic miR203 suppresses ΔNp63α expression, proliferation and colony formation. The anti-clonogenic effects mediated by miR203 require suppression of ΔNp63α. In addition, ectopic miR203 promotes mesenchymal-to-epithelial transition and disrupts activities associated with epithelial stem cells. These studies support a model in which induction of miR203 mediates forfeiture of self-renewing capacity via suppression of ΔNp63α and may also have anti-tumorigenic activity through its reduction of EMT and cancer stem cell populations
Clinical pharmacokinetics and pharmacodynamics of cerliponase alfa, enzyme replacement therapy for CLN2 disease by intracerebroventricular administration
Cerliponase alfa is recombinant human TPP1 delivered by intracerebroventricular (ICV) infusion for CLN2, a pediatric neurodegenerative disease caused by deficiency in lysosomal enzyme TPP1. We report the PK and PD of cerliponase alfa, the first ICV enzyme replacement therapy, characterized in a Phase 1/2 study. Escalating doses (30-300 mg every two weeks, Q2W) followed by 300 mg Q2W for ≥48 weeks were administered in 24 patients aged ≥3 years. Concentrations peaked in CSF at the end of ~4-hour ICV infusion and 8 hours thereafter in plasma. Plasma exposure was 300-1000 fold lower than in CSF, with no correlation in the magnitude of Cmax or AUC between body sites. There was no apparent accumulation in CSF or plasma exposure with Q2W dosing. Inter- and intra-patient variability of AUC, respectively, were 31-49% and 24% in CSF versus 59-103% and 80% in plasma. PK variability was not explained by baseline demographics, as gender, age, weight, and CLN2 disease severity score did not appear to impact CSF or plasma PK. No apparent correlation was noted between CSF or plasma PK and incidence of adverse events (pyrexia, hypersensitivity, seizure, and epilepsy) or presence of antidrug antibodies in CSF and serum. There was no relationship between magnitude of CSF exposure and efficacy (change in CLN2 score from baseline), indicating maximum benefit was obtained across the range of exposures with 300 mg Q2W. Data from this small trial of ultra-rare disease were leveraged to adequately profile cerliponase alfa and support 300 mg ICV Q2W for CLN2 treatment
Concept for Predicting Vibrations in Machine Tools Using Machine Learning
Vibrations have a significant influence on quality and costs in metal
cutting processes. Existing methods for predicting vibrations in machine tools enable an informed choice of process settings, however they rely on costly equipment and specialised staff. Therefore, this contribution proposes to reduce the modelling effort required by using machine learning based on data gathered during production. The approach relies on two sub-models, representing the machine structure and machining process respectively. A method is proposed for initialising and updating the models in production
ERR2 and ERR3 promote the development of gamma motor neuron functional properties required for proprioceptive movement control
The ability of terrestrial vertebrates to effectively move on land is integrally linked to the diversification of motor neurons into types that generate muscle force (alpha motor neurons) and types that modulate muscle proprioception, a task that in mammals is chiefly mediated by gamma motor neurons. The diversification of motor neurons into alpha and gamma types and their respective contributions to movement control have been firmly established in the past 7 decades, while recent studies identified gene expression signatures linked to both motor neuron types. However, the mechanisms that promote the specification of gamma motor neurons and/or their unique properties remained unaddressed. Here, we found that upon selective loss of the orphan nuclear receptors ERR2 and ERR3 (also known as ERR beta, ERR gamma or NR3B2, NR3B3, respectively) in motor neurons in mice, morphologically distinguishable gamma motor neurons are generated but do not acquire characteristic functional properties necessary for regulating muscle proprioception, thus disrupting gait and precision movements. Complementary gain-of-function experiments in chick suggest that ERR2 and ERR3 could operate via transcriptional activation of neural activity modulators to promote a gamma motor neuron biophysical signature of low firing thresholds and high firing rates. Our work identifies a mechanism specifying gamma motor neuron functional properties essential for the regulation of proprioceptive movement control
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Accelerometry: a practical tool for understanding the role of energy in agriculture-nutrition linkages
Research on nutrition in low and middle-income countries (LMICs) has mainly focused on how policy and project interventions can bring about changes in diets, while changes in physical activity has been largely overlooked. Productivity-enhancing activities can impact the calorie deficits of the undernourished via their effects on energy intakes and energy expenditure. Rural transformation also has an effect on lifestyles of rural people. Changes in diets and physical activity patterns has a profound effect on livelihoods. The energy expenditure dimension has previously not been incorporated in the analysis of agriculture-nutrition linkages and livelihood analysis. Most studies capturing energy expenditure in rural households in LMICs have use methods that require a controlled setting. These can be quite expensive and are often very practical for population-level studies. Accelerometry has advanced in recent years, providing a new opportunity to collect more accurate population-level data on energy expenditure
PET Imaging of Soluble Yttrium-86-Labeled Carbon Nanotubes in Mice
The potential medical applications of nanomaterials are shaping the landscape of the nanobiotechnology field and driving it forward. A key factor in determining the suitability of these nanomaterials must be how they interface with biological systems. Single walled carbon nanotubes (CNT) are being investigated as platforms for the delivery of biological, radiological, and chemical payloads to target tissues. CNT are mechanically robust graphene cylinders comprised of sp(2)-bonded carbon atoms and possessing highly regular structures with defined periodicity. CNT exhibit unique mechanochemical properties that can be exploited for the development of novel drug delivery platforms. In order to evaluate the potential usefulness of this CNT scaffold, we undertook an imaging study to determine the tissue biodistribution and pharmacokinetics of prototypical DOTA-functionalized CNT labeled with yttrium-86 and indium-111 ((86)Y-CNT and (111)In-CNT, respectively) in a mouse model.The (86)Y-CNT construct was synthesized from amine-functionalized, water-soluble CNT by covalently attaching multiple copies of DOTA chelates and then radiolabeling with the positron-emitting metal-ion, yttrium-86. A gamma-emitting (111)In-CNT construct was similarly prepared and purified. The constructs were characterized spectroscopically, microscopically, and chromatographically. The whole-body distribution and clearance of yttrium-86 was characterized at 3 and 24 hours post-injection using positron emission tomography (PET). The yttrium-86 cleared the blood within 3 hours and distributed predominantly to the kidneys, liver, spleen and bone. Although the activity that accumulated in the kidney cleared with time, the whole-body clearance was slow. Differential uptake in these target tissues was observed following intravenous or intraperitoneal injection.The whole-body PET images indicated that the major sites of accumulation of activity resulting from the administration of (86)Y-CNT were the kidney, liver, spleen, and to a much less extent the bone. Blood clearance was rapid and could be beneficial in the use of short-lived radionuclides in diagnostic applications
High Performance In Vivo Near-IR (>1 {\mu}m) Imaging and Photothermal Cancer Therapy with Carbon Nanotubes
Short single-walled carbon nanotubes (SWNTs) functionalized by PEGylated
phospholipids are biologically non-toxic and long-circulating nanomaterials
with intrinsic near infrared photoluminescence (NIR PL), characteristic Raman
spectra, and strong optical absorbance in the near infrared (NIR). This work
demonstrates the first dual application of intravenously injected SWNTs as
photoluminescent agents for in vivo tumor imaging in the 1.0-1.4 {\mu}m
emission region and as NIR absorbers and heaters at 808 nm for photothermal
tumor elimination at the lowest injected dose (70 {\mu}g of SWNT/mouse,
equivalent to 3.6 mg/kg) and laser irradiation power (0.6 W/cm2) reported to
date. Ex vivo resonance Raman imaging revealed the SWNT distribution within
tumors at a high spatial resolution. Complete tumor elimination was achieved
for large numbers of photothermally treated mice without any toxic side effects
after more than six months post-treatment. Further, side-by-side experiments
were carried out to compare the performance of SWNTs and gold nanorods (AuNRs)
at an injected dose of 700 {\mu}g of AuNR/mouse (equivalent to 35 mg/kg) in NIR
photothermal ablation of tumors in vivo. Highly effective tumor elimination
with SWNTs was achieved at 10 times lower injected doses and lower irradiation
powers than for AuNRs. These results suggest there are significant benefits of
utilizing the intrinsic properties of biocompatible SWNTs for combined cancer
imaging and therapy.Comment: Nanoresearch, in pres
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Biomarkers and Noncalcified Coronary Artery Plaque Progression in Older Men Treated With Testosterone.
ObjectiveRecent results from the Cardiovascular Trial of the Testosterone Trials showed that testosterone treatment of older men with low testosterone was associated with greater progression of noncalcified plaque (NCP). We evaluated the effect of anthropometric measures and cardiovascular biomarkers on plaque progression in individuals in the Testosterone Trial.MethodsThe Cardiovascular part of the trial included 170 men aged 65 years or older with low testosterone. Participants received testosterone gel or placebo gel for 12 months. The primary outcome was change in NCP volume from baseline to 12 months, as determined by coronary computed tomography angiography (CCTA). We assayed several markers of cardiovascular risk and analyzed each marker individually in a model as predictive variables and change in NCP as the dependent variable.ResultsOf 170 enrollees, 138 (73 testosterone, 65 placebo) completed the study and were available for the primary analysis. Of 10 markers evaluated, none showed a significant association with the change in NCP volume, but a significant interaction between treatment assignment and waist-hip ratio (WHR) (P = 0.0014) indicated that this variable impacted the testosterone effect on NCP volume. The statistical model indicated that for every 0.1 change in the WHR, the testosterone-induced 12-month change in NCP volume increased by 26.96 mm3 (95% confidence interval, 7.72-46.20).ConclusionAmong older men with low testosterone treated for 1 year, greater WHR was associated with greater NCP progression, as measured by CCTA. Other biomarkers and anthropometric measures did not show statistically significant association with plaque progression
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