We present an improved search for neutrinoless double-beta (0νββ) decay of ^{136}Xe in the KamLAND-Zen experiment. Owing to purification of the xenon-loaded liquid scintillator, we achieved a ...significant reduction of the ^{110m}Ag contaminant identified in previous searches. Combining the results from the first and second phase, we obtain a lower limit for the 0νββ decay half-life of T_{1/2}^{0ν}>1.07×10^{26} yr at 90% C.L., an almost sixfold improvement over previous limits. Using commonly adopted nuclear matrix element calculations, the corresponding upper limits on the effective Majorana neutrino mass are in the range 61-165 meV. For the most optimistic nuclear matrix elements, this limit reaches the bottom of the quasidegenerate neutrino mass region.
Targeting cells specifically based on receptor expression levels remains an area of active research to date. Selective binding of receptors cannot be achieved by increasing the individual binding ...strength, as this does not account for differing distributions of receptor density across healthy and diseased cells. Engaging receptors above a threshold concentration would be desirable in devising selective diagnostics. Integrins are prime target candidates as they are readily available on the cell surface and have been reported to be overexpressed in diseases. Insights into their spatial organization would therefore be advantageous to design selective targeting agents. Here, we investigated the effect of activation method on integrin α5β1 clustering by immunofluorescence and modeled the global neighbor distances with input from an immuno-staining assay and image processing of microscopy images. This data was used to engineer spatially-controlled DNA-scaffolded bivalent ligands, which we used to compare trends in spatial-selective binding observed across HUVEC, CHO and HeLa in resting versus activated conditions in confocal microscopy images. For HUVEC and CHO, the data demonstrated an improved selectivity and localisation of binding for smaller spacings ~7 nm and ~24 nm, in good agreement with the model. A deviation from the mode predictions for HeLa was observed, indicative of a clustered, instead of homogeneous, integrin organization. Our findings demonstrate how low-technology imaging methods can guide the design of spatially controlled ligands to selectively differentiate between cell type and integrin activation state.
Macrophage interaction with oxidized low-density lipoprotein (oxLDL) leads to its differentiation into foam cells and cytokine production, contributing to atherosclerosis development. In a previous ...study, we showed that CD36 and the receptor for platelet-activating factor (PAFR) are required for oxLDL to activate gene transcription for cytokines and CD36. Here, we investigated the localization and physical interaction of CD36 and PAFR in macrophages stimulated with oxLDL. We found that blocking CD36 or PAFR decreases oxLDL uptake and IL-10 production. OxLDL induces IL-10 mRNA expression only in HEK293T expressing both receptors (PAFR and CD36). OxLDL does not induce IL-12 production. The lipid rafts disruption by treatment with βCD reduces the oxLDL uptake and IL-10 production. OxLDL induces co-immunoprecipitation of PAFR and CD36 with the constitutive raft protein flotillin-1, and colocalization with the lipid raft-marker GM1-ganglioside. Finally, we found colocalization of PAFR and CD36 in macrophages from human atherosclerotic plaques. Our results show that oxLDL induces the recruitment of PAFR and CD36 into the same lipid rafts, which is important for oxLDL uptake and IL-10 production. This study provided new insights into how oxLDL interact with macrophages and contributing to atherosclerosis development.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We study a local antisymmetric spin-orbit (ASO) coupling effect on a triangular-triple-quantum-dot (TTQD) system as a theoretical proposal for a new application of the Kondo physics to nanoscale ...devices. The electric polarization induced by the Kondo effect is strongly correlated with the spin configurations and molecular orbital degrees of freedom in the TTQD. In particular, an abrupt sign reversal of the emergent electric polarization is associated with a quantum critical point in a magnetic field, which can also be controlled by the ASO coupling that changes the mixing weight of different orbital components in the TTQD ground state.
We report a 64-year-old Japanese woman with a history of progressive loss of motor function and painful swelling of large joints. At the age of 54, profound calcification appeared around the shoulder ...and hip joints, which did not heal after repeated surgical resections. Iliac bone biopsy revealed osteomalacic changes. Laboratory data showed low serum alkaline phosphatase (ALP) activity and a high urine phosphoethanolamine (PEA) concentration with normal serum calcium, phosphate, and fibroblast growth factor 23 (FGF23) levels. Subsequent genetic analysis of the
ALPL
gene confirmed the diagnosis of hypophosphatasia (HPP) with the identification of a heterozygous single nucleotide deletion, c.1559delT (p.Leu520ArgfsX86). We started a mineral-targeted enzyme replacement therapy, asfotase alfa (AA), to treat the patient’s musculoskeletal symptoms. A follow-up bone biopsy after 12 months of AA treatment showed improvement of osteomalacia. Calcified deposits around the large joints were unchanged radiographically. To our knowledge, this is the first report of a patient with an adult-onset HPP who presented with profound calcification around multiple joints. Nonspecific clinical signs and symptoms in patients with adult-onset HPP often result in delayed diagnosis or misdiagnosis. We propose that bone biopsy and genetic analysis should be considered along with laboratory analysis for all patients with ectopic calcification around joints of unknown etiology for accurate diagnosis and better treatment.
The oxidative process of LDL particles generates molecules which are structurally similar to platelet-activating factor (PAF), and some effects of oxidized LDL (oxLDL) have been shown to be dependent ...on PAF receptor (PAFR) activation. In a previous study, we showed that PAFR is required for upregulation of CD36 and oxLDL uptake. In the present study we analyzed the molecular mechanisms activated by oxLDL in human macrophages and the contribution of PAFR to this response. Human adherent monocytes/macrophages were stimulated with oxLDL. Uptake of oxLDL and CD36 expression were determined by flow cytometry; MAP kinases and Akt phosphorylation by Western blot; IL-8 and MCP-1 concentration by ELISA and mRNA expression by real-time PCR. To investigate the participation of the PI3K/Akt pathway, Gαi-coupled protein or PAFR, macrophages were treated with LY294002, pertussis toxin or with the PAFR antagonists WEB2170 and CV3988, respectively before addition of oxLDL. It was found that the addition of oxLDL to human monocytes/macrophages activates the PI3K/Akt pathway which in turn activates the MAPK (p38 and JNK). Phosphorylation of Akt requires the engagement of PAFR and a Gαi-coupled protein. The upregulation of CD36 protein and the uptake of oxLDL as well as the IL-8 production are dependent on PI3K/Akt pathway activation. The increased CD36 protein expression is dependent on PAFR and Gαi-coupled protein. Transfection studies using HEK 293t cells showed that oxLDL uptake occurs with either PAFR or CD36, but IL-8 production requires the co-transfection of both PAFR and CD36. These findings show that PAFR has a pivotal role in macrophages response to oxLDL and suggest that pharmacological intervention at the level of PAFR activation might be beneficial in atherosclerosis.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Exploring drug targets based on disease-associated molecular mechanisms during development is crucial for the generation of novel prevention and treatment strategies for neurodevelopmental ...psychiatric conditions. We report that prefrontal cortex (PFC)-specific postnatal knockdown of DISC1 via in utero electroporation combined with an inducible knockdown expression system drives deficits in synaptic GABAA function and dendritic development in pyramidal neurons, as well as abnormalities in sensorimotor gating, albeit without profound memory deficits. We show for the first time that DISC1 is specifically involved in regulating cell surface expression of α2 subunit-containing GABAA receptors in immature developing neurons, but not after full maturation. Notably, pharmacological intervention with α2/3 subtype-selective GABAA receptor positive allosteric modulators during the early postnatal period ameliorates dendritic deficits and behavioral abnormalities induced by knockdown of DISC1. These findings highlight a critical role of DISC1-mediated disruption of postnatal GABA signaling in aberrant PFC maturation and function.
Whether Bickerstaff's brainstem encephalitis (BBE) is a distinct disease or a subtype of Fisher syndrome (FS) is unclear as there have been no clinical studies with sufficiently large numbers of ...patients with FS or BBE. Our aim was to clarify the nosological relationship. Medical records of patients suffering acute ophthalmoplegia and ataxia within four weeks of onset were reviewed. BBE was the diagnosis for patients with impaired consciousness, FS for those with clear consciousness and areflexia. Clinical features, neuroimages, and laboratory findings were analyzed. Patients were grouped as having BBE (n = 53), FS (n = 466), or as unclassified (n = 62). The BBE and FS groups had similar features; positive serum anti-GQ1b IgG antibody (68 % versus 83 %), antecedent
Campylobacter jejuni
infection (23 % versus 21 %), CSF albuminocytological dissociation (46 % versus 76 %), brain MRI abnormality (11 % versus 2 %), and abnormal EEG findings (57 % versus 25 %). BBE (n = 4) and FS (n = 28) subgroups underwent detailed electrophysiological testing. Both groups frequently showed absent soleus H-reflexes, but normal sensory nerve conduction (75 % versus 74 %) and a 1-Hz power spectrum peak on postural body sway analysis (67 % versus 72 %). Common autoantibodies, antecedent infections, and MRI and neurophysiological results found in this large study offer conclusive evidence that Bickerstaff's brainstem encephalitis and Fisher syndrome form a continuous spectrum with variable CNS and PNS involvement.
We recently reported that paracrine Fibroblast Growth Factor 2 (FGF2) triggers senescence in Ras-driven Y1 and 3T3(Ras) mouse malignant cell lines. Here, we show that although FGF2 activates ...mitogenic pathways in these Ras-dependent malignant cells, it can block cell proliferation and cause a G2/M arrest. These cytostatic effects of FGF2 are inhibited by PD173074, an FGF receptor (FGFR) inhibitor. To determine which downstream pathways are induced by FGF2, we tested specific inhibitors targeting mitogen-activated protein kinase (MEK), phosphatidylinositol 3 kinase (PI3K) and protein kinase C (PKC). We show that these classical mitogenic pathways do not mediate the cytostatic activity of FGF2. On the other hand, the inhibition of Src family kinases rescued Ras-dependent malignant cells from the G2/M irreversible arrest induced by FGF2. Taken together, these data indicate a growth factor-sensitive point in G2/M that likely involves FGFR/Ras/Src pathway activation in a MEK, PI3K and PKC independent manner.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
There have been only a limited number of reports on primary adult T cell lymphoma/leukemia (ATL) in the bone. This is a case report of a 75-year-old patient initially reporting multiple bone pains ...that were attributed to osteolytic ATL. The patient developed spontaneous chest/back pain and visited a local hospital. Laboratory tests showed high levels of alkaline phosphatase (ALP), and computed tomography (CT) revealed skeletal lesions with osteolysis. Although multiple myeloma was initially suspected, the results of bone marrow aspiration and bone biopsy were inconsistent. After he was referred to our hospital, mild hypercalcemia (10.4 mg/dL) with low-normal intact parathyroid hormone (PTH) (27 pg/mL), low parathyroid hormone-related protein (PTHrP), and elevated 1,25-dihydroxy vitamin D (1,25OH
2
D) levels (136 pg/mL) narrowed the differential diagnosis down to lymphomatous and granulomatous diseases, and then, the high serum soluble IL-2 receptor (3,450 U/mL) and the flower cells recognized in the peripheral blood sample suggested the involvement of ATL. Finally, the reevaluation of the iliac bone biopsy sample led us to the histological diagnosis of ATL infiltration in the bone. The subsequent two courses of chemotherapy in addition to denosumab resulted in an objective partial metabolic response indicated in 18-fluorine-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). Although very rare, the bone involvement of ATL could be used for the differential diagnosis for local osteolytic bone pain in addition to multiple myeloma and metastatic bone diseases.