624 research outputs found
Search for electromagnetic properties of the neutrinos at the LHC
Exclusive production of neutrinos via photon-photon fusion provides an
excellent opportunity to probe electromagnetic properties of the neutrinos at
the LHC. We explore the potential of processes pp-> p gamma gamma p -> p nu
anti-nu p and pp -> p gamma gamma p -> p nu anti-nu Z p to probe
neutrino-photon and neutrino-two photon couplings. We show that these reactions
provide more than seven orders of magnitude improvement in neutrino-two photon
couplings compared to LEP limits.Comment: 11 pages, 4 tables, New backgrounds have been adde
TDP-43 stabilises the processing intermediates of mitochondrial transcripts
The 43-kDa trans-activating response region DNA-binding protein 43 (TDP-43) is a product of a causative gene for amyotrophic lateral sclerosis (ALS). Despite of accumulating evidence that mitochondrial dysfunction underlies the pathogenesis of TDP-43–related ALS, the roles of wild-type TDP-43 in mitochondria are unknown. Here, we show that the small TDP-43 population present in mitochondria binds directly to a subset of mitochondrial tRNAs and precursor RNA encoded in L-strand mtDNA. Upregulated expression of TDP-43 stabilised the processing intermediates of mitochondrial polycistronic transcripts and their products including the components of electron transport and 16S mt-rRNA, similar to the phenotype observed in cells deficient for mitochondrial RNase P. Conversely, TDP-43 deficiency reduced the population of processing intermediates and impaired mitochondrial function. We propose that TDP-43 has a novel role in maintaining mitochondrial homeostasis by regulating the processing of mitochondrial transcripts
TDP-43 induces p53-mediated cell death of cortical progenitors and immature neurons
TAR DNA-binding protein 43 (TDP-43) is a key player in neurodegenerative diseases including frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). Accumulation of TDP-43 is associated with neuronal death in the brain. How increased and disease-causing mutant forms of TDP-43 induce cell death remains unclear. Here we addressed the role of TDP-43 during neural development and show that reduced TDP-43 causes defects in neural stem/progenitor cell proliferation but not cell death. However, overexpression of wild type and TDP-43A315T proteins induce p53-dependent apoptosis of neural stem/progenitors and human induced pluripotent cell (iPS)-derived immature cortical neurons. We show that TDP-43 induces expression of the proapoptotic BH3-only genes Bbc3 and Bax, and that p53 inhibition rescues TDP-43 induced cell death of embryonic mouse, and human cortical neurons, including those derived from TDP-43G298S ALS patient iPS cells. Hence, an increase in wild type and mutant TDP-43 induces p53-dependent cell death in neural progenitors developing neurons and this can be rescued. These findings may have important implications for accumulated or mutant TDP-43 induced neurodegenerative diseases
Reduced phosphorylation of brain insulin receptor substrate and Akt proteins in apolipoprotein-E4 targeted replacement mice
10.1038/srep03754Scientific Reports4
Thyroid and pituitary gland development from hatching through metamorphosis of a teleost flatfish, the Atlantic halibut
Fish larval development, not least the spectacular
process of flatfish metamorphosis, appears to be
under complex endocrine control, many aspects of
which are still not fully elucidated. In order to obtain
data on the functional development of two major
endocrine glands, the pituitary and the thyroid, during
flatfish metamorphosis, histology, immunohistochemistry
and in situ hybridization techniques were applied on
larvae of the Atlantic halibut (Hippoglossus hippoglossus),
a large, marine flatfish species, from hatching
through metamorphosis. The material was obtained
from a commercial hatchery. Larval age is defined as
day-degrees (D =accumulated daily temperature from
hatching). Sporadic thyroid follicles are first detected in
larvae at 142 D (27 days post-hatch), prior to the
completion of yolk sack absorption. Both the number
and activity of the follicles increase markedly after yolk
sack absorption and continue to do so during subsequent
development. The larval triiodothyronine (T3)
and thyroxine (T4) content increases, subsequent to yolk
absorption, and coincides with the proliferation of thyroid
follicles. A second increase of both T3 and T4 occurs
around the start of metamorphosis and the T3 content
further increases at the metamorphic climax. Overall,
the T3 content is lower than T4. The pituitary gland can
first be distinguished as a separate organ at the yolk sack
stage. During subsequent development, the gland becomes
more elongated and differentiates into neurohypophysis (NH), pars distalis (PD) and pars intermedia
(PI). The first sporadic endocrine pituitary cells are observed
at the yolk sack stage, somatotrophs (growth
hormone producing cells) and somatolactotrophs (somatolactin
producing cells) are first observed at 121 D
(23 days post-hatch), and lactotrophs (prolactin producing
cells) at 134 D (25 days post-hatch). Scarce
thyrotrophs are evident after detection of the first thyroid
follicles (142 D ), but coincident with a phase in
which follicle number and activity increase (260 D ).
The somatotrophs are clustered in the medium ventral
region of the PD, lactotrophs in the anterior part of the
PD and somatolactotrophs are scattered in the mid and
posterior region of the pituitary. At around 600 D ,
coinciding with the start of metamorphosis, somatolactotrophs
are restricted to the interdigitating tissue of the
NH. During larval development, the pituitary endocrine
cells become more numerous. The present data on thyroid
development support the notion that thyroid hormones
may play a significant role in Atlantic halibut
metamorphosis. The time of appearance and the subsequent
proliferation of pituitary somatotrophs, lactotrophs,
somatolactotrophs and thyrotrophs indicate at
which stages of larval development and metamorphosis
these endocrine cells may start to play active regulatory
roles.This work has been carried out within the
projects ‘‘Endocrine Control as a Determinant of Larval Quality in
Fish Aquaculture’’ (CT-96-1422) and ‘‘Arrested development: The
Molecular and Endocrine Basis of Flatfish Metamorphosis’’
(Q5RS-2002-01192), with financial support from the Commission
of the European Communities. However, it does not necessarily
reflect the Commission’s views and in no way anticipates its future
policy in this area. This project was further supported by the
Swedish Council for Agricultural and Forestry Research and Pluriannual
funding to CCMAR by the Portuguese Science and
Technology Council
Metformin Prevents Nigrostriatal Dopamine Degeneration Independent of AMPK Activation in Dopamine Neurons
Metformin is a widely prescribed drug used to treat type-2 diabetes, although recent studies show it has wide ranging effects to treat other diseases. Animal and retrospective human studies indicate that Metformin treatment is neuroprotective in Parkinson’s Disease (PD), although the neuroprotective mechanism is unknown, numerous studies suggest the beneficial effects on glucose homeostasis may be through AMPK activation. In this study we tested whether or not AMPK activation in dopamine neurons was required for the neuroprotective effects of Metformin in PD. We generated transgenic mice in which AMPK activity in dopamine neurons was ablated by removing AMPK beta 1 and beta 2 subunits from dopamine transporter expressing neurons. These AMPK WT and KO mice were then chronically exposed to Metformin in the drinking water then exposed to MPTP, the mouse model of PD. Chronic Metformin treatment significantly attenuated the MPTP-induced loss of Tyrosine Hydroxylase (TH) neuronal number and volume and TH protein concentration in the nigrostriatal pathway. Additionally, Metformin treatment prevented the MPTP-induced elevation of the DOPAC:DA ratio regardless of genotype. Metformin also prevented MPTP induced gliosis in the Substantia Nigra. These neuroprotective actions were independent of genotype and occurred in both AMPK WT and AMPK KO mice. Overall, our studies suggest that Metformin’s neuroprotective effects are not due to AMPK activation in dopaminergic neurons and that more research is required to determine how metformin acts to restrict the development of PD
A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)
Meeting abstrac
Multi-messenger observations of a binary neutron star merger
On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta
Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease
Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.
Haematozoan parasites of the lizard Ameiva ameiva (Teiidae) from Amazonian Brazil: a preliminary note
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