SIRT1 is a NAD
+-dependent deacetylase that governs a number of genetic programs to cope with changes in the nutritional status of cells and organisms. Behavioral responses to food abundance are ...important for the survival of higher animals. Here we used mice with increased or decreased brain SIRT1 to show that this sirtuin regulates anxiety and exploratory drive by activating transcription of the gene encoding the monoamine oxidase A (
MAO-A) to reduce serotonin levels in the brain. Indeed, treating animals with MAO-A inhibitors or selective serotonin reuptake inhibitors (SSRIs) normalized anxiety differences between wild-type and mutant animals. SIRT1 deacetylates the brain-specific helix-loop-helix transcription factor NHLH2 on lysine 49 to increase its activation of the MAO-A promoter. Both common and rare variations in the
SIRT1 gene were shown to be associated with risk of anxiety in human population samples. Together these data indicate that SIRT1 mediates levels of anxiety, and this regulation may be adaptive in a changing environment of food availability.
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► SIRT1 activity in the brain alters murine exploratory drive and anxiety ► SIRT1 activates
MAO-A and decreases serotonin via deacetylation of NHLH2 ► Common variants of
SIRT1 are associated with mood disorder prevalence in humans
The deacetylase SIRT1 modulates brain serotonin levels to impact anxiety behavior in mice, and in humans, genetic variants in the
SIRT1 gene are associated with the prevalence of mood disorders.
Thermal Transport in 3D Nanostructures Zhan, Haifei; Nie, Yihan; Chen, Yongnan ...
Advanced functional materials,
02/2020, Letnik:
30, Številka:
8
Journal Article
Recenzirano
Odprti dostop
This work summarizes the recent progress on the thermal transport properties of 3D nanostructures, with an emphasis on experimental results. Depending on the applications, different 3D nanostructures ...can be prepared or designed to either achieve a low thermal conductivity for thermal insulation or thermoelectric devices or a high thermal conductivity for thermal interface materials used in the continuing miniaturization of electronics. A broad range of 3D nanostructures are discussed, ranging from colloidal crystals/assemblies, array structures, holey structures, hierarchical structures, to 3D nanostructured fillers for metal matrix composites and polymer composites. Different factors that impact the thermal conductivity of these 3D structures are compared and analyzed. This work provides an overall understanding of the thermal transport properties of various 3D nanostructures, which will shed light on the thermal management at nanoscale.
Diverse 3D nanostructures are fabricated to meet specific thermal management purposes, including nanoarchitectures (such as colloidal assemblies and carbon nanotube arrays) and nanocomposites from polymer matrix or metal matrix. It is shown that the use of nanostructuring of materials is an effective strategy to modify the thermal conductivity of materials.
Here, we show that a subset of breast cancers express high levels of the type 2 phosphatidylinositol-5-phosphate 4-kinases α and/or β (PI5P4Kα and β) and provide evidence that these kinases are ...essential for growth in the absence of p53. Knocking down PI5P4Kα and β in a breast cancer cell line bearing an amplification of the gene encoding PI5P4K β and deficient for p53 impaired growth on plastic and in xenografts. This growth phenotype was accompanied by enhanced levels of reactive oxygen species (ROS) leading to senescence. Mice with homozygous deletion of both TP53 and PIP4K2B were not viable, indicating a synthetic lethality for loss of these two genes. Importantly however, PIP4K2A−/−, PIP4K2B+/−, and TP53−/− mice were viable and had a dramatic reduction in tumor formation compared to TP53−/− littermates. These results indicate that inhibitors of PI5P4Ks could be effective in preventing or treating cancers with mutations in TP53.
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•A subset of breast cancers express high levels of PI5P4Kα and/or β•PI5P4Ks play a critical role in HER2-positive and p53-defective breast cancers•Suppression of PI5P4K expression results in enhanced ROS and cellular senescence•PI5P4K inhibitors could be effective in treating cancers with mutations in TP53
Inhibition of a class of lipid kinases inhibits tumor growth in the absence of p53, revealing an opportunity to develop kinase inhibitors to treat a broad swath of human cancers.
Avian host life history traits have been hypothesized to predict rates of infection by haemosporidian parasites. Using molecular techniques, we tested this hypothesis for parasites from three ...haemosporidian genera (Plasmodium, Haemoproteus, and Leucocytozoon) collected from a diverse sampling of birds in northern Malawi. We found that host life history traits were significantly associated with parasitism rates by all three parasite genera. Nest type and nest location predicted infection probability for all three parasite genera, whereas flocking behavior is an important predictor of Plasmodium and Haemoproteus infection and habitat is an important predictor of Leucocytozoon infection. Parasite prevalence was 79.1% across all individuals sampled, higher than that reported for comparable studies from any other region of the world. Parasite diversity was also exceptionally high, with 248 parasite cytochrome b lineages identified from 152 host species. A large proportion of Plasmodium, Haemoproteus, and Leucocytozoon parasite DNA sequences identified in this study represent new, previously undocumented lineages (n = 201; 81% of total identified) based on BLAST queries against the avian malaria database, MalAvi.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To assess the outcomes in actively managed extremely preterm infants after admission to a neonatal intensive care unit.
Retrospective cohort of 255 infants born at 22-25 weeks of gestation between ...2006 and 2015 at a single study institution. Infants were excluded for congenital anomaly, death in delivery room, or parental request for palliation (n = 7). Neurodevelopmental outcomes were analyzed for 169 of 214 survivors (78.9%) at 18-22 months of corrected age. Outcomes were evaluated using the Mann-Whitney U, χ2, or Fisher exact test, where appropriate. In addition, cognitive scores of the Bayley Scales of Infant-Toddler Development (3rd edition) were assessed using generalized estimating equations.
Seventy infants born at 22-23 weeks of gestation (22 weeks, n = 20; 23 weeks, n = 50) and 178 infants born at 24-25 weeks of gestation (24 weeks, n = 79; 25 weeks, n = 99 infants) were included. Survival to hospital discharge of those surviving to NICU admission was 78% (55/70; 95% CI, 69%-88%) at 22-23 weeks and 89% (159/178; 95% CI, 84%-93% at 24-25 weeks; P = .02). No or mild neurodevelopmental impairment in surviving infants was 64% (29/45; 95% CI, 50%-77%) at 22-23 weeks and 76% (94/124; 95% CI, 68%-83%; P = .16) at 24-25 weeks.
Although survival was lower in infants born at 22-23 weeks than at 24-25 weeks of gestation, the majority of survivors in both groups had positive outcomes with no or mild neurodevelopmental impairments. Further evaluation of school performance is warranted.
Protists, which are single-celled eukaryotes, critically influence the ecology and chemistry of marine ecosystems, but genome-based studies of these organisms have lagged behind those of other ...microorganisms. However, recent transcriptomic studies of cultured species, complemented by meta-omics analyses of natural communities, have increased the amount of genetic information available for poorly represented branches on the tree of eukaryotic life. This information is providing insights into the adaptations and interactions between protists and other microorganisms and macroorganisms, but many of the genes sequenced show no similarity to sequences currently available in public databases. A better understanding of these newly discovered genes will lead to a deeper appreciation of the functional diversity and metabolic processes in the ocean. In this Review, we summarize recent developments in our understanding of the ecology, physiology and evolution of protists, derived from transcriptomic studies of cultured strains and natural communities, and discuss how these novel large-scale genetic datasets will be used in the future.
The widespread availability and diversity of open-source microcontrollers paired with off-the-shelf electronics and 3D printed technology has led to the creation of a wide range of low-cost ...scientific instruments, including microscopes, spectrometers, sensors, data loggers, and other tools that can be used for research, education, and experimentation. These devices can be used to explore a wide range of scientific topics, from biology and chemistry to physics and engineering. In this study, we designed and built a multifunction fluorescent open source in vivo/in vitro imaging system (openIVIS) system that integrates a Raspberry Pi with commercial cameras and LEDs with 3D printed structures combined with an acrylic housing. Our openIVIS provides three excitation wavelengths of 460 nm, 520 nm, and 630 nm integrated with Python control software to enable fluorescent measurements across the full visible light spectrum. To demonstrate the potential applications of our system, we tested its performance against a diverse set of experiments including laboratory assays (measuring fluorescent dyes, using optical nanosensors, and DNA gel electrophoresis) to potentially fieldable applications (plant and mineral imaging). We also tested the potential use for a high school biology environment by imaging small animals and tracking their development over the course of ten days. Our system demonstrated its ability to measure a wide dynamic range fluorescent response from millimolar to picomolar concentrations in the same sample while measuring responses across visible wavelengths. These results demonstrate the power and flexibility of open-source hardware and software and how it can be integrated with customizable manufacturing to create low-cost scientific instruments with a wide range of applications. Our study provides a promising model for the development of low-cost instruments that can be used in both research and education.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Pexa-Vec (pexastimogene devacirepvec, JX-594) is an oncolytic and immunotherapeutic vaccinia virus designed to destroy cancer cells through viral lysis and induction of granulocyte-macrophage ...colony-stimulating factor (GM-CSF)-driven tumor-specific immunity. Pexa-Vec has undergone phase 1 and 2 testing alone and in combination with other therapies in adult patients, via both intratumoral and intravenous administration routes. We sought to determine the safety of intratumoral administration in pediatric patients. In a dose-escalation study using either 106 or 107 plaque-forming units per kilogram, we performed one-time injections in up to three tumor sites in five pediatric patients and two injections in one patient. Ages at study entry ranged from 4 to 21 years, and their cancer diagnoses included neuroblastoma, hepatocellular carcinoma, and Ewing sarcoma. All toxicities were ≤ grade 3. The most common side effects were sinus fever and sinus tachycardia. All three patients at the higher dose developed asymptomatic grade 1 treatment-related skin pustules that resolved within 3–4 weeks. One patient showed imaging evidence suggestive of antitumor biological activity. The two patients tested for cellular immunoreactivity to vaccinia antigens showed strong responses. Overall, our study suggests Pexa-Vec is safe to administer to pediatric patients by intratumoral administration and could be studied further in this patient population.
The excellent mechanical properties of carbon nanofibers bring promise for energy-related applications. Through in silico studies and continuum elasticity theory, here we show that the ultra-thin ...carbon nanothreads-based bundles exhibit a high mechanical energy storage density. Specifically, the gravimetric energy density is found to decrease with the number of filaments, with torsion and tension as the two dominant contributors. Due to the coupled stresses, the nanothread bundle experiences fracture before reaching the elastic limit of any individual deformation mode. Our results show that nanothread bundles have similar mechanical energy storage capacity compared to (10,10) carbon nanotube bundles, but possess their own advantages. For instance, the structure of the nanothread allows us to realize the full mechanical energy storage potential of its bundle structure through pure tension, with a gravimetric energy density of up to 1.76 MJ kg
, which makes them appealing alternative building blocks for energy storage devices.
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