Topological Kagome Magnet Co3Sn2S2 Thin Flakes with High Electron Mobility and Large Anomalous Hall Effect.

Magnetic Weyl semimetals attract considerable interest not only for their topological quantum phenomena but also as an emerging materials class for realizing quantum anomalous Hall effect in the two-dimensional limit. A shandite compound Co3Sn2S2 with layered kagome-lattices is one such material, where vigorous efforts have been devoted to synthesize the two-dimensional crystal. Here, we report a synthesis of Co3Sn2S2 thin flakes with a thickness of 250 nm by chemical vapor transport method. We find that this facile bottom-up approach allows the formation of large-sized Co3Sn2S2 thin flakes of high-quality, where we identify the largest electron mobility (∼2600 cm2 V-1 s-1) among magnetic topological semimetals, as well as the large anomalous Hall conductivity (∼1400 Ω-1 cm-1) and anomalous Hall angle (∼32%) arising from the Berry curvature. Our study provides a viable platform for studying high-quality thin flakes of magnetic Weyl semimetal and stimulate further research on unexplored topological phenomena in the two-dimensional limit.

Microglial NFκB-TNFα hyperactivation induces obsessive-compulsive behavior in mouse models of progranulin-deficient frontotemporal dementia.

Frontotemporal dementia (FTD) is the second most common dementia before 65 years of age. Haploinsufficiency in the progranulin (GRN) gene accounts for 10% of all cases of familial FTD. GRN mutation carriers have an increased risk of autoimmune disorders, accompanied by elevated levels of tissue necrosis factor (TNF) α. We examined behavioral alterations related to obsessive-compulsive disorder (OCD) and the role of TNFα and related signaling pathways in FTD patients with GRN mutations and in mice lacking progranulin (PGRN). We found that patients and mice with GRN mutations displayed OCD and self-grooming (an OCD-like behavior in mice), respectively. Furthermore, medium spiny neurons in the nucleus accumbens, an area implicated in development of OCD, display hyperexcitability in PGRN knockout mice. Reducing levels of TNFα in PGRN knockout mice abolished excessive self-grooming and the associated hyperexcitability of medium spiny neurons of the nucleus accumbens. In the brain, PGRN is highly expressed in microglia, which are a major source of TNFα. We therefore deleted PGRN specifically in microglia and found that it was sufficient to induce excessive grooming. Importantly, excessive grooming in these mice was prevented by inactivating nuclear factor κB (NF-κB) in microglia/myeloid cells. Our findings suggest that PGRN deficiency leads to excessive NF-κB activation in microglia and elevated TNFα signaling, which in turn lead to hyperexcitability of medium spiny neurons and OCD-like behavior.

Novel pre-therapeutic scoring system using patient and haematological data to predict facial palsy prognosis.

OBJECTIVES: We describe a novel scoring system, the facial Palsy Prognosis Prediction score (PPP score), which we test for reliability in predicting pre-therapeutic prognosis of facial palsy. We aimed to use readily available patient data that all clinicians have access to before starting treatment. DESIGN: Multicenter case series with chart review. SETTING: Three tertiary care hospitals. PARTICIPANTS: We obtained haematological and demographic data from 468 facial palsy patients who were treated between 2010 and 2014 in three tertiary care hospitals. Patients were categorised as having Bell's palsy or Ramsey Hunt's palsy. MAIN OUTCOME MEASURES: We compared the data of recovered and unrecovered patients. PPP scores consisted of combinatorial threshold values of continuous patient data (eg platelet count) and categorical variables (eg gender) that best predicted recovery. We created separate PPP scores for Bell's palsy patients (PPP-B) and for Ramsey Hunt's palsy patients (PPP-H). RESULTS: The PPP-B score included age (≥65 years), gender (male) and neutrophil-to-lymphocyte ratio (≥2.9). The PPP-H score included age (≥50 years), monocyte rate (≥6.0%), mean corpuscular volume (≥95 fl) and platelet count (≤200 000 /µL). Patient recovery rate significantly decreased with increasing PPP scores (both PPP-B and PPP-H) in a step-wise manner. PPP scores (ie PPP-B score and PPP-H score) ≥2 were associated with worse than average prognosis. CONCLUSIONS: Palsy Prognosis Prediction scores are useful for predicting prognosis of facial palsy before beginning treatment.

The first report of the thyroid function of haemophilic patients with HIV/HCV co-infection in Japan.

INTRODUCTION: A high incidence of thyroid dysfunction is reported in patients with HIV or HCV mono-infection. We have conducted a periodic medical examination including the thyroid function for haemophilic patients with HIV/HCV co-infection due to contaminated blood products. METHODS: We examined the thyroid function (as assessed by the FT3, FT4 and TSH levels) in 45 haemophilic patients, including thyroglobulin and auto-antibody, antithyroglobulin antibody, antithyroid peroxidase antibody and anti-TSH receptor antibody in 28 patients. RESULTS: All the patients were males (median age: 42 years; range: 29-66). The median values of thyroid function were FT3 3.36 pg mL(-1) , FT4 1.125 ng mL(-1) and TSH 1.65 µIU mL(-1) . Five patients (11.1%) had high TSH levels. In 28 patients in whom the presence of auto-antibodies was examined, the median age was 47 years of age. The median value of thyroglobulin was 16 ng mL(-1) and two patients showed high levels of thyroglobulin. The presence of anti-TSH receptor antibody of all the patients was negative, but one patient (3.5%) was positive of antithyroid peroxidase antibody and antithyroglobulin antibody. CONCLUSIONS: Since 0.68-3.6% of the general healthy population is reported to show hypothyroidism, our data showed that the proportion of hypothyroidism in haemophilic patients with HIV/HCV co-infection was more frequent than that of the normal population.

New Short-Lived Isotope

Two short-lived isotopes ^{221}U and ^{222}U were produced as evaporation residues in the fusion reaction ^{50}Ti+^{176}Yb at the gas-filled recoil separator TASCA. An α decay with an energy of E_{α}=9.31(5) MeV and half-life T_{1/2}=4.7(7) µs was attributed to ^{222}U. The new isotope ^{221}U was identified in α-decay chains starting with E_{α}=9.71(5) MeV and T_{1/2}=0.66(14) µs leading to known daughters. Synthesis and detection of these unstable heavy nuclei and their descendants were achieved thanks to a fast data readout system. The evolution of the N=126 shell closure and its influence on the stability of uranium isotopes are discussed within the framework of α-decay reduced width.

Studies on expression of aldehyde dehydrogenase in normal and cancerous tissues of thyroids.

Recently published articles have reported the controversial data regarding expression of aldehyde dehydrogenase isozyme 1A1 (ALDH1A1), a potential candidate marker for normal and cancer stem cells (CSCs), in thyroid tissues. These data prompted us to re-evaluate expression of ALDH1A1 in normal and cancerous thyroid tissues by 2 different means. The first method was immunohistochemistry with 2 different anti-ALDH1A1 antibodies from distinct companies. Following validating the integrity of these 2 antibodies by Western blotting with ALDH-expressing and nonexpressing cancer cell lines and immunohistochemistry with breast and colon tissues, we report here significant and comparable expression of ALDH1A1 in both normal and cancerous thyroid tissues with both antibodies. Next, relative expression levels of ALDH isozymes were evaluated by reverse transcription-polymerase chain reaction (RT-PCR), revealing that ALDH1A1 was the most highly expressed isozyme followed by ALDH9A1 and relative expression patterns of isozymes were very similar in normal and cancerous tissues. All these data demonstrate that thyroid cells of normal and cancer origins do express ALDH1A1 and to a lesser extent 9A1. Further study will be necessary to study functional significance of ALDH1A1 in the function and behaviors of thyroid normal and cancer stem cells.

Evaluation of the operative methods for Graves' disease.

AIM: In Japan, surgery for Graves' disease (GD), which is considered to be a radical therapy, has been restricted by various guidelines. Nevertheless, some patients benefit from surgery. We sought to identify a reasonable operative method for GD by comparing the efficacy and safety among patients undergoing different extents of thyroidectomy. METHODS: A total of 162 patients underwent thyroidectomy for GD between 2003 and 2012 in our department. We compared the clinical factors among those who underwent subtotal thyroidectomy (ST), near-total thyroidectomy (NTT), and total thyroidectomy (TT). RESULTS: The ST, NTT, and TT groups included 111, 21, and 30 patients, respectively. The patient sex, period between disease onset and surgery, and preoperative thyroidal function were not substantially different among the three groups. With regard to surgical variables, the duration of surgery, amount of blood loss, and postoperative length of hospitalization were not substantially different among the three groups. Postoperative recurrent laryngeal nerve (RLN) palsy was transient in all cases, but the rate was significantly higher in the TT group compared to the other two groups (P<0.001). The incidences of transient hypocalcemia and permanent hypoparathyroidism were not substantially different among the groups. The proportion of patients who required the postoperative administration of levothyroxine was significantly lower in the ST group compared to the TT and NTT groups. Hyperthyroidism recurrence was noted in eight patients in the ST group (7.2%). CONCLUSION: NTT for GD is thus considered to be a reasonable operative method regarding both efficacy and safety.

48Ca+249Bk fusion reaction leading to element Z = 117: long-lived α-decaying 270Db and discovery of 266Lr.

The superheavy element with atomic number Z=117 was produced as an evaporation residue in the (48)Ca+(249)Bk fusion reaction at the gas-filled recoil separator TASCA at GSI Darmstadt, Germany. The radioactive decay of evaporation residues and their α-decay products was studied using a detection setup that allowed measuring decays of single atomic nuclei with half-lives between sub-µs and a few days. Two decay chains comprising seven α decays and a spontaneous fission each were identified and are assigned to the isotope (294)117 and its decay products. A hitherto unknown α-decay branch in (270)Db (Z = 105) was observed, which populated the new isotope (266)Lr (Z = 103). The identification of the long-lived (T(1/2) = 1.0(-0.4)(+1.9) h) α-emitter (270)Db marks an important step towards the observation of even more long-lived nuclei of superheavy elements located on an "island of stability."

Growth hormone ameliorates adipose dysfunction during oxidative stress and inflammation and improves glucose tolerance in obese mice.

Patients with adult growth hormone deficiency exhibit visceral fat accumulation, which gives rise to a cluster of metabolic disorders such as impaired glucose tolerance and dyslipidemia. Plasma growth hormone levels are lower in obese patients with metabolic syndrome than in healthy subjects. Here we examined the hypothesis that exogenous growth hormone administration regulates function of adipose tissue to improve glucose tolerance in diet-induced obese mice. Twelve-week-old obese male C57BL/6 J mice received bovine growth hormone daily for 6 weeks. In epididymal fat, growth hormone treatment antagonized diet-induced changes in the gene expression of adiponectin, leptin, and monocyte chemoattractant protein-1, and significantly increased the gene expression of interleukin-10 and CD206. Growth hormone also suppressed the accumulation of oxidative stress marker, thiobarbituric acid-reactive substances, in the epididymal fat and enhanced the gene expression of anti-oxidant enzymes. Moreover, growth hormone significantly restored glucose tolerance in obese mice. In cultured 3T3-L1 adipocytes, growth hormone prevented the decline in adiponectin gene expression in the presence of hydrogen peroxide. These results suggest that growth hormone administration ameliorates glucose intolerance in obese mice presumably by decreasing adipose mass, oxidative stress, and chronic inflammation in the visceral fat.

Cyclooxygenase-1 inhibition reduces amyloid pathology and improves memory deficits in a mouse model of Alzheimer's disease.

Several epidemiological and preclinical studies suggest that non-steroidal anti-inflammatory drugs (NSAIDs), which inhibit cyclooxygenase (COX), reduce the risk of Alzheimer's disease (AD) and can lower ß-amyloid (Aß) production and inhibit neuroinflammation. However, follow-up clinical trials, mostly using selective cyclooxygenase (COX)-2 inhibitors, failed to show any beneficial effect in AD patients with mild to severe cognitive deficits. Recent data indicated that COX-1, classically viewed as the homeostatic isoform, is localized in microglia and is actively involved in brain injury induced by pro-inflammatory stimuli including Aß, lipopolysaccharide, and interleukins. We hypothesized that neuroinflammation is critical for disease progression and selective COX-1 inhibition, rather than COX-2 inhibition, can reduce neuroinflammation and AD pathology. Here, we show that treatment of 20-month-old triple transgenic AD (3 × Tg-AD) mice with the COX-1 selective inhibitor SC-560 improved spatial learning and memory, and reduced amyloid deposits and tau hyperphosphorylation. SC-560 also reduced glial activation and brain expression of inflammatory markers in 3 × Tg-AD mice, and switched the activated microglia phenotype promoting their phagocytic ability. The present findings are the first to demonstrate that selective COX-1 inhibition reduces neuroinflammation, neuropathology, and improves cognitive function in 3 × Tg-AD mice. Thus, selective COX-1 inhibition should be further investigated as a potential therapeutic approach for AD.

Reduced Autophagy in Aged Trigeminal Neurons Causes Amyloid ß Diffusion.

The relationship between oral health and the development of Alzheimer's disease (AD) in the elderly is not yet well understood. In this regard, the association between aging or neurodegeneration of the trigeminal nervous system and the accumulation of amyloid-ß(1-42) (Aß42) oligomers in the pathogenesis of AD is unknown. We focused on selective autophagy in the trigeminal mesencephalic nucleus (Vmes) and the diffusion of Aß42 oligomers with respect to aging of the trigeminal nervous system and whether the degeneration of Vmes neurons affects the diffusion of Aß42 oligomers. We used female 2- to 8-mo-old transgenic 3xTg-AD mice and AppNL-G-F knock-in mice and immunohistochemically examined aging-related changes in selective autophagy and Aß42 oligomer processing in the Vmes, which exhibits high amyloid-ß (Aß) expression. We induced degeneration of Vmes neurons by extracting the maxillary molars and examined the changes in Aß42 oligomer kinetics. Autophagosome-like membranes, which stained positive for Aß, HO-1, and LC3B, were observed in Vmes neurons of 3xTg-AD mice, while there was weak immunoreactivity of the membranes for intraneuronal Aß in AppNL-G-F mice. By contrast, there was strong immunopositivity for extracellular Aß42 oligomers with the formation of Aß42 oligomer clusters in AppNL-G-F mice. The expression of Rubicon, which indicates age-related deterioration of autophagy, increased the diffusion of Aß42 oligomer with the age of Vmes neurons. Tooth extraction increased the extracellular immunopositivity for Aß42 oligomers in AppNL-G-F mice. These results suggest that autophagy maintains homeostasis in Vmes neurons and that deterioration of autophagy due to aging or neurodegeneration leads to the diffusion of Aß42 oligomers into the extracellular space and possibly the development of AD.

CCR3 plays a role in murine age-related cognitive changes and T-cell infiltration into the brain.

Targeting immune-mediated, age-related, biology has the potential to be a transformative therapeutic strategy. However, the redundant nature of the multiple cytokines that change with aging requires identification of a master downstream regulator to successfully exert therapeutic efficacy. Here, we discovered CCR3 as a prime candidate, and inhibition of CCR3 has pro-cognitive benefits in mice, but these benefits are not driven by an obvious direct action on central nervous system (CNS)-resident cells. Instead, CCR3-expressing T cells in the periphery that are modulated in aging inhibit infiltration of these T cells across the blood-brain barrier and reduce neuroinflammation. The axis of CCR3-expressing T cells influencing crosstalk from periphery to brain provides a therapeutically tractable link. These findings indicate the broad therapeutic potential of CCR3 inhibition in a spectrum of neuroinflammatory diseases of aging.

Selective targeting of microglia by quantum dots.

BACKGROUND: Microglia, the resident immune cells of the brain, have been implicated in brain injury and various neurological disorders. However, their precise roles in different pathophysiological situations remain enigmatic and may range from detrimental to protective. Targeting the delivery of biologically active compounds to microglia could help elucidate these roles and facilitate the therapeutic modulation of microglial functions in neurological diseases. METHODS: Here we employ primary cell cultures and stereotaxic injections into mouse brain to investigate the cell type specific localization of semiconductor quantum dots (QDs) in vitro and in vivo. Two potential receptors for QDs are identified using pharmacological inhibitors and neutralizing antibodies. RESULTS: In mixed primary cortical cultures, QDs were selectively taken up by microglia; this uptake was decreased by inhibitors of clathrin-dependent endocytosis, implicating the endosomal pathway as the major route of entry for QDs into microglia. Furthermore, inhibiting mannose receptors and macrophage scavenger receptors blocked the uptake of QDs by microglia, indicating that QD uptake occurs through microglia-specific receptor endocytosis. When injected into the brain, QDs were taken up primarily by microglia and with high efficiency. In primary cortical cultures, QDs conjugated to the toxin saporin depleted microglia in mixed primary cortical cultures, protecting neurons in these cultures against amyloid beta-induced neurotoxicity. CONCLUSIONS: These findings demonstrate that QDs can be used to specifically label and modulate microglia in primary cortical cultures and in brain and may allow for the selective delivery of therapeutic agents to these cells.

Periventricular and deep white matter leukoaraiosis have a closer association with cerebral microbleeds than age.

BACKGROUND: Taking an advantage of the high sensitivity of 3D T2*-weighted gradient-recalled-echo (GRE) imaging to cerebral microbleeds, we investigated the relationship between cerebral microbleeds and leukoaraiosis. METHODS: Participants aged 40 years or more have been evaluated for the presence of cerebral microbleeds using 3D T2*-GRE sequence since 2006. The severity of periventricular hyperintensity (PVH) and deep white matter hyperintensity (DWMH) on fluid attenuated inversion recovery images was assessed using Fazekas rating scales. Multivariate logistic regression analyses were conducted after adjustment for stroke subtype, age, PVH, DWMH, hypertension, dementia, and use of platelet aggregation inhibitors. Additionally, we examined the association between cerebral microbleeds and other covariates using a Pearson's correlation analysis. RESULTS: Amongst 389 patients, 67 patients had a single microbleed and 93 had multiple microbleeds. The prevalence of microbleeds was 83% amongst 53 patients with intracerebral hemorrhage (ICH), 49% amongst 173 with infarction, and 20% amongst 163 without any type of stroke. In the multivariate analyses, the odds ratio (95% CIs) of microbleed detection was 10.1, (4.12-24.8) for ICH, 2.33 (1.12-4.85) for atherosclerotic infarction, 1.66 (1.10-2.48) for PVH, and 1.49 (1.02-2.19) for DWMH. In the Pearson's correlation analysis, cerebral microbleeds were closely related to PVH (Pearson's correlation coefficient; 0.48) and DWMH (0.37), compared with age (0.16). CONCLUSIONS: High-grade PVH, high-grade DWMH, ICH, and atherosclerotic infarction were significantly independent predictors for cerebral microbleeds. In addition, we found that the grades of PVH and DWMH have a closer association with the number of cerebral microbleeds than age.

Quantitative evaluation of bone development of the distal phalanx of the cow hind limb using computed tomography.

Computed tomography (CT) was performed on 400 claws (200 inner and 200 outer claws) of 100 pairs of bovine hind limbs to investigate the etiological theory that an exacerbating factor for ulceration is exostosis of the tuberculum flexorium within the distal phalanx. A variety of morphological changes of the tuberculum flexorium of bovine hind limb claws was visualized by 3-dimensional CT, and the geometry of these claws suggested a growth pattern of bone development with respect to the assumed daily loading patterns. This growth occurs initially at the abaxial caudal aspect of the distal phalanx and is followed by horizontal progression toward the axial aspect. The length of downward bone development on the solar face of the distal phalanx was 2.73±1.32 mm in the outer claws, significantly greater than in the inner claws (2.38±0.96 mm). Ratios of downward (vertical) bone development to the thickness of the subcutis and the corium (VerBD ratios) did not differ between the outer and inner claws (36.7 vs. 38.3%, respectively). Ratios of horizontal bone development to the axial-to-abaxial line of the tuberculum flexorium (HorBD ratios) were approximately 60% for both outer and inner claws. These quantitative measures regarding horizontal and vertical bone development within the distal phalanx were positively correlated with age and VerBD ratios (r=0.53 and r=0.36 for the inner and outer claws, respectively). Correlations between claw width of the outer claw and length of vertical bone development (r=0.43), the HorBD ratio (r=0.51), and the VerBD ratio (r=0.42) suggested that the relative size difference between the inner and outer claws enhances bone development in the outer claw. Correlation coefficients between VerBD and HorBD ratios (r=0.52 and 0.63 for the inner and outer claws, respectively) suggested that horizontal and vertical bone development occurs as a synchronized process within the tuberculum flexorium. This age-related progress of bone development within the tuberculum flexorium is associated with increased exposure to several exacerbating factors and the laminitic process.

Molecular and histological correlates of cognitive decline across age in male C57BL/6J mice.

INTRODUCTION: Increasing age is the number one risk factor for developing cognitive decline and neurodegenerative disease. Aged humans and mice exhibit numerous molecular changes that contribute to a decline in cognitive function and increased risk of developing age-associated diseases. Here, we characterize multiple age-associated changes in male C57BL/6J mice to understand the translational utility of mouse aging. METHODS: Male C57BL/6J mice from various ages between 2 and 24 months of age were used to assess behavioral, as well as, histological and molecular changes across three modalities: neuronal, microgliosis/neuroinflammation, and the neurovascular unit (NVU). Additionally, a cohort of 4- and 22-month-old mice was used to assess blood-brain barrier (BBB) breakdown. Mice in this cohort were treated with a high, acute dose of lipopolysaccharide (LPS, 10 mg/kg) or saline control 6 h prior to sacrifice followed by tail vein injection of 0.4 kDa sodium fluorescein (100 mg/kg) 2 h later. RESULTS: Aged mice showed a decline in cognitive and motor abilities alongside decreased neurogenesis, proliferation, and synapse density. Further, neuroinflammation and circulating proinflammatory cytokines were increased in aged mice. Additionally, we found changes at the BBB, including increased T cell infiltration in multiple brain regions and an exacerbation in BBB leakiness following chemical insult with age. There were also a number of readouts that were unchanged with age and have limited utility as markers of aging in male C57BL/6J mice. CONCLUSIONS: Here we propose that these changes may be used as molecular and histological readouts that correspond to aging-related behavioral decline. These comprehensive findings, in the context of the published literature, are an important resource toward deepening our understanding of normal aging and provide an important tool for studying aging in mice.

Fyn kinase regulates the association between amyloid precursor protein and Dab1 by promoting their localization to detergent-resistant membranes.

The adaptor protein Disabled1 (Dab1) interacts with amyloid precursor protein (APP) and decreases its pathological processing, an effect mediated by Fyn tyrosine kinase. Fyn is highly enriched in lipid rafts, a major site of pathological APP processing. To investigate the role of Fyn in the localization and phosphorylation of APP and Dab1 in lipid rafts, we isolated detergent-resistant membrane (DRM) fractions from wild-type and Fyn knock-out mice. In wild-type mice, all of the Fyn kinase, 17% of total APP, and 33% of total Dab1 were found in DRMs. Nearly all of the tyrosine phosphorylated forms of APP and Dab1 were in DRMs. APP and Dab1 co-precipitated both in and out of DRM fractions, indicating an association that is independent of subcellular localization. Fyn knock-out mice had decreased APP, Dab1, and tyrosine-phosphorylated Dab1 in DRMs but increased co-immunoprecipitation of DRM APP and Dab1. Expression of phosphorylation deficient APP or Dab1 constructs revealed that phosphorylation of APP increases, whereas phosphorylation of Dab1 decreases, the interaction between APP and Dab1. Consistent with these observations, Reelin treatment led to increased Dab1 phosphorylation and decreased association between APP and Dab1. Reelin also caused increased localization of APP and Dab1 to DRMs, an effect that was not seen in Fyn knock-out neurons. These findings suggest that Reelin treatment promotes the localization of APP and Dab1 to DRMs, and affects their phosphorylation by Fyn, thus regulating their interaction.

The cytoplasmic adaptor protein X11alpha and extracellular matrix protein Reelin regulate ApoE receptor 2 trafficking and cell movement.

The goal of this study was to determine the effect of X11alpha on ApoE receptor 2 (ApoEr2) trafficking and the functional significance of this interaction on cell movement in MCF 10A epithelial cells. We found that X11alpha increased surface levels of ApoEr2 by 64% compared to vector control, as determined by surface protein biotinylation. To examine the functional significance of this effect, we tested whether ApoEr2 played a novel role in cell movement in a wound-healing assay. We found that overexpression of ApoEr2 in MCF 10A cells increased cell migration velocity by 87% (P<0.01, n=4) compared to GFP control. Cotransfection of X11alpha had an additive effect on average velocity compared to ApoEr2 alone (13%; P<0.05, n=4). In addition, we tested whether ApoEr2 ligands altered the effect of ApoEr2 on cell movement. We found that treatment with concentrated medium containing the extracellular matrix protein Reelin, but not control medium, further increased the velocity of ApoEr2- but not APP-transfected cells (20%; P<0.001, n=4). Similarly, Reelin treatment increased cell velocity in the presence of ApoEr2 and X11alpha (10%; P<0.05, n=4). In the present study, we are the first to demonstrate that ApoEr2 regulates cell movement, and both X11alpha and Reelin enhance this effect.

Hydrogen sensing properties of protective-layer-coated single-walled carbon nanotubes with palladium nanoparticle decoration.

Protective-layer-coated single-walled carbon nanotubes (SWNTs) with palladium nanoparticle decoration (Pd-SiO(2)-SWNTs) were fabricated and their sensing properties for hydrogen (H(2)) were investigated. SWNTs were coated with a 3-4 nm thick SiO(2) layer by pulsed laser deposition and subsequently decorated with Pd nanoparticles by electron beam evaporation. Even though the SWNTs were completely surrounded by a protective layer, Pd-SiO(2)-SWNTs responded to H(2) down to a concentration of 1 part per million. Compared with the Pd nanoparticle-decorated SWNTs without a protective layer (Pd-SWNTs), Pd-SiO(2)-SWNTs exhibited highly stable sensor responses with variations of less than 20%; Pd-SWNTs showed a variation of 80%. The density of the Pd-SWNTs significantly decreased after the sensing test, while that of the Pd-SiO(2)-SWNTs with the netlike structure remained unchanged. The hydrogen sensing mechanism of the Pd-SiO(2)-SWNTs was attributed to the chemical gating effect on the SWNTs due to dipole layer formation by hydrogen atoms trapped at the Pd-SiO(2) interface. Moreover, the relationship between H(2) concentration and sensor response can be described by the Langmuir isotherm for dissociative adsorption.