426 research outputs found
Effects of Smoothing Functions in Cosmological Counts-in-Cells Analysis
A method of counts-in-cells analysis of galaxy distribution is investigated
with arbitrary smoothing functions in obtaining the galaxy counts. We explore
the possiblity of optimizing the smoothing function, considering a series of
-weight Epanechnikov kernels. The popular top-hat and Gaussian smoothing
functions are two special cases in this series. In this paper, we mainly
consider the second moments of counts-in-cells as a first step. We analytically
derive the covariance matrix among different smoothing scales of cells, taking
into account possible overlaps between cells. We find that the Epanechnikov
kernel of is better than top-hat and Gaussian smoothing functions in
estimating cosmological parameters. As an example, we estimate expected
parameter bounds which comes only from the analysis of second moments of galaxy
distributions in a survey which is similar to the Sloan Digital Sky Survey.Comment: 33 pages, 10 figures, accepted for publication in PASJ (Vol.59, No.1
in press
Effect of thyroid statuses on sodium/iodide symporter (NIS) gene expression in the extrathyroidal tissues in mice
<p>Abstract</p> <p>Background</p> <p>Iodide that is essential for thyroid hormone synthesis is actively transported into the thyroid follicular cells via sodium/iodide symporter (NIS) protein in vertebrates. It is well known that NIS expression in thyroid is regulated by the thyroid statuses mainly through thyroid stimulating hormone (TSH). Although <it>NIS </it>mRNA expressions in extrathyroidal tissues have been qualitatively reported, their regulation by thyroid statuses has not been well clarified.</p> <p>Methods</p> <p>Male ICR mice aged four weeks were assigned into three groups (control, hypothyroid, and hyperthyroid). Hypothyroid group of mice were treated with 0.02% methimazole in drinking water and hyperthyroid group of mice received intraperitoneal injection (4 ΞΌg <sub>L</sub>-T<sub>4 </sub>twice a week) for four weeks. <it>NIS </it>mRNA expression levels in the tissues were evaluated using Northern blot hybridization and quantitative real-time RTPCR (qPCR). Additionally, end-point RTPCR for the thyroid follicular cell-characteristic genes (TSH receptor, <it>TSHR</it>; thyroid transcription factor-1, <it>TTF1</it>; and paired box gene 8, <it>Pax8</it>) was carried out.</p> <p>Results</p> <p>By Northern blot analysis, <it>NIS </it>mRNA was detected in thyroid and stomach. In addition to these organs, qPCR revealed the expression also in the submandibular gland, colon, testis, and lung. Expression of <it>NIS </it>mRNA in thyroid was significantly increased in hypothyroid and decreased in hyperthyroid group. Trends of <it>NIS </it>mRNA expression in extrathyroidal tissues were not in line with that in the thyroid gland in different thyroid statuses. Only in lung, <it>NIS </it>mRNA was regulated by thyroid statuses but in opposite way compared to the manner in the thyroid gland. There were no extrathyroidal tissues that expressed all three characteristic genes of thyroid follicular cells.</p> <p>Conclusions</p> <p><it>NIS </it>mRNA expression in the thyroid gland was up-regulated in hypothyroid mice and was down-regulated in hyperthyroid mice, suggesting that <it>NIS </it>mRNA in the thyroid gland is regulated by thyroid statuses. In contrast, <it>NIS </it>mRNA expression in extrathyroidal tissues was not altered by thyroid statuses although it was widely expressed. Lack of responsiveness of <it>NIS </it>mRNA expressions in extrathyroidal tissues reemphasizes additional functions of NIS protein in extrathyroidal tissues other than iodide trapping.</p
PD-L1 upregulation by lytic induction of Epstein-Barr Virus
Epstein-Barr virus (EBV) is an etiologic agent of infectious mononucleosis and several malignancies. Here, we found that reactivation of EBV resulted in increased programmed cell death-ligand 1 (PD-L1) expression in a cell type-dependent manner. Lytic induction in EBV-positive Akata, AGS, MutuI, and Jijoye cell lines increased PD-L1 levels, but cells such as EBV-negative Akata, MutuIII, and P3HR1 did not have increased PD-L1. EBV in the P3HR1 cell line has a deletion in the EBNA2 gene, while EBV in its parental cell line, Jijoye, has the complete EBNA2 gene. PD-L1 expression by lytic induction was reduced when EBNA2 was knocked down. In addition, pharmacological inhibition indicated involvement of nuclear factor kappa B, mitogen-activated protein kinase, and AKT signaling. These results suggest that EBV likely evades immunity by inducing PD-L1 upon reactivation, through the increased expression of EBNA2 and activation of signaling pathways.journal articl
Association between reduced serum BDNF levels and insomnia with short sleep duration among female hospital nurses
Objective: Previous studies have suggested that brain-derived neurotrophic factor (BDNF) is associated with sleep regulation in humans. However, its relationship with self-reported sleep problems has not been clarified. The aim of the present study was to examine the association between serum BDNF levels and sleep problems among hospital nurses. Methods: Participants were enrolled from among nurses working at a general hospital in Tokyo, Japan. Data from 577 women (age: 35.45 Β± 10.90 years) were analyzed. This cross-sectional survey was conducted from November to December 2015. Serum BDNF concentrations were evaluated. Participants completed a self-reported questionnaire on sleep including the presence or absence of insomnia symptoms (ie, difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), and early morning awakening [EMA]), and sleep duration. Insomnia with short sleep duration (ISS) was defined as: DIS, or DMS, or EMA; and <6 h sleep duration. Results: Among 577 participants, 21.3% reported insomnia, 41.4% slept less than 6 h, and finally 12.5% suffered from ISS. Serum BDNF levels were significantly lower in subjects with ISS than in those without ISS. The serum BDNF levels in insomniacs were significantly lower than in non-insomniacs for short sleep duration (<6 h), while serum BDNF levels did not differ between insomniacs and non-insomniacs for normal sleep duration (β₯6 h). Conclusion: This is the first documented study to indicate that ISS is associated with reduced serum BDNF levels. These results may lead to clarification of the underlying pathophysiological relationship between BDNF and poor sleep
The ubiquitination-deubiquitination cycle on the ribosomal protein eS7A is crucial for efficient translation
Ubiquitination is a major post-translational modification of ribosomal proteins. The role of ubiquitination in the regulation of ribosome functions is still being elucidated. However, the importance of ribosome deubiquitination remains unclear. Here, we show that the cycle of ubiquitination and deubiquitination of the 40S ribosome subunit eS7 is important for efficient translation. eS7 ubiquitination at lysine 83 is required for efficient protein translation. We identified Otu2 and Ubp3 as the deubiquitinating enzymes for eS7. An otu2Ξubp3Ξ mutation caused a defect in protein synthesis. Ubp3 inhibited polyubiquitination of eS7 in polysomes to keep eS7 in a mono-ubiquitinated form, whereas Otu2 was specifically bound to the free 40S ribosome and promoted the dissociation of mRNAs from 40S ribosomes in the recycling step. Our results provide clues for understanding the molecular mechanism of the translation system via a ubiquitination-deubiquitination cycle
Efficient production of infectious viruses requires enzymatic activity of Epstein-Barr virus protein kinase
AbstractThe Epstein-Barr virus (EBV) BGLF4 gene product is the only protein kinase encoded by the virus genome. In order to elucidate its physiological roles in viral productive replication, we here established a BGLF4-knockout mutant and a revertant virus. While the levels of viral DNA replication of the deficient mutant were equivalent to those of the wild-type and the revertant, virus production was significantly impaired. Expression of the BGLF4 protein in trans fully complemented the low yield of the mutant virus, while expression of a kinase-dead (K102I) form of the protein failed to restore the virus titer. These results demonstrate that BGLF4 plays a significant role in production of infectious viruses and that the kinase activity is crucial
Inactivation of the Rcan2 Gene in Mice Ameliorates the Age- and Diet-Induced Obesity by Causing a Reduction in Food Intake
Obesity is a serious international health problem that increases the risk of several diet-related chronic diseases. The genetic factors predisposing to obesity are little understood. Rcan2 was originally identified as a thyroid hormone-responsive gene. In the mouse, two splicing variants that harbor distinct tissue-specific expression patterns have been identified: Rcan2-3 is expressed predominately in the brain, whereas Rcan2-1 is expressed in the brain and other tissues such as the heart and skeletal muscle. Here, we show that Rcan2 plays an important role in the development of age- and diet-induced obesity. We found that although the loss of Rcan2 function in mice slowed growth in the first few weeks after birth, it also significantly ameliorated age- and diet-induced obesity in the mice by causing a reduction in food intake rather than increased energy expenditure. Rcan2 expression was most prominent in the ventromedial, dorsomedial and paraventricular hypothalamic nuclei governing energy balance. Fasting and refeeding experiment showed that only Rcan2-3 mRNA expression is up-regulated in the hypothalamus by fasting, and loss of Rcan2 significantly attenuates the hyperphagic response to starvation. Using double-mutant (Lepob/ob Rcan2β/β) mice, we were also able to demonstrate that Rcan2 and leptin regulate body weight through different pathways. Our findings indicate that there may be an Rcan2-dependent mechanism which regulates food intake and promotes weight gain through a leptin-independent pathway. This study provides novel information on the control of body weight in mice and should improve our understanding of the mechanisms of obesity in humans
Degradation of Phosphorylated p53 by Viral Protein-ECS E3 Ligase Complex
p53-signaling is modulated by viruses to establish a host cellular environment advantageous for their propagation. The Epstein-Barr virus (EBV) lytic program induces phosphorylation of p53, which prevents interaction with MDM2. Here, we show that induction of EBV lytic program leads to degradation of p53 via an ubiquitin-proteasome pathway independent of MDM2. The BZLF1 protein directly functions as an adaptor component of the ECS (Elongin B/C-Cul2/5-SOCS-box protein) ubiquitin ligase complex targeting p53 for degradation. Intringuingly, C-terminal phosphorylation of p53 resulting from activated DNA damage response by viral lytic replication enhances its binding to BZLF1 protein. Purified BZLF1 protein-associated ECS could be shown to catalyze ubiquitination of phospho-mimetic p53 more efficiently than the wild-type in vitro. The compensation of p53 at middle and late stages of the lytic infection inhibits viral DNA replication and production during lytic infection, suggesting that the degradation of p53 is required for efficient viral propagation. Taken together, these findings demonstrate a role for the BZLF1 protein-associated ECS ligase complex in regulation of p53 phosphorylated by activated DNA damage signaling during viral lytic infection
Transcatheter retrieval of an Amplatzer Vascular Plug
Introduction: An Amplatzer Vascular Plug (AVP), which was designed as a permanent occluding device derived from the Amplatzer Septal Occluder and Amplatzer Duct Occluder, is a useful embolic device that can be precisely deployed in medium to large vessels with high resistance to migration. However, migration of these Amplatzer devices has been reported as a relatively rare but major complication. Case report: A 59-year-old woman was referred for the treatment of advanced pancreatic body cancer; after systemic chemotherapy, distal pancreatectomy with en bloc celiac axis resection (DP-CAR) was planned as curative treatment. Therefore, preoperative embolisation of the common hepatic artery (CHA) for arterial redistribution was performed. Although a 6-mm AVP II was deployed at the mid-portion of the CHA, the AVP migrated to the proper hepatic artery. Although migrated AVP retrieval using a goose neck snare was attempted, it was impossible to retrieve it into the 5-F guiding sheath. Therefore, the AVP was delivered to the splenic artery, which was planned to be resected in DP-CAR. Finally, a 10-mm AVP II was redeployed at the proximal portion of the CHA, and complete occlusion was achieved. Conclusions: When AVP retrieval is not possible, delivery to the other arteries having lesser influence might be an alternate technique
LODEWAVE Phase II (LOng-Duration balloon Experiment of gravity WAVE over Antarctica)
The 14th Symposium on Polar Science/Interdisciplinary sessions [IW] Whole Atmosphere, Thu. 16 Nov. / 3F Multipurpose Conference room, Institute of Statistical Mathematicsconference objec
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