Absence of Nogo-B (Reticulon 4B) Facilitates Hepatic Stellate Cell Apoptosis and Diminishes Hepatic Fibrosis in Mice

Nogo-B (reticulon 4B) accentuates hepatic fibrosis and cirrhosis, but the mechanism remains unclear. The aim of this study was to identify the role of Nogo-B in hepatic stellate cell (HSC) apoptosis in cirrhotic livers. Cirrhosis was generated by carbon tetrachloride inhalation in wild-type (WT) and Nogo-A/B knockout (Nogo-B KO) mice. HSCs were isolated from WT and Nogo-B KO mice and cultured for activation and transformation to myofibroblasts (MF-HSCs). Human hepatic stellate cells (LX2 cells) were used to assess apoptotic responses of activated HSCs after silencing or overexpressing Nogo-B. Livers from cirrhotic Nogo-B KO mice showed significantly reduced fibrosis (P < 0.05) compared with WT mice. Apoptotic cells were more prominent in fibrotic areas of cirrhotic Nogo-B KO livers. Nogo-B KO MF-HSCs showed significantly increased Levels of apoptotic markers, cleaved poly (ADP-ribose) polymerase, and caspase-3 and -8 (P < 0.05) compared with WT MF-HSCs in response to staurosporine. Treatment with tunicamycin, an endoplasmic reticulum stress inducer, increased cleaved caspase-3 and -8 levels in Nogo-B KO MF-HSCs compared with WT MF-HSCs (P < 0.01). In LX2 cells, Nogo-B knockdown enhanced apoptosis in response to staurosporine, whereas Nogo-B overexpression inhibited apoptosis. The absence of Nogo-B enhances apoptosis of HSCs in experimental cirrhosis. Selective blockade of Nogo-B in HSCs may represent a potential therapeutic strategy to mitigate liver fibrosis. (Am J Pathol 2013, 182: 786-795; http://dx.doLorg/10.1016Aajpath.2012.11.032

Faraday dispersion functions of galaxies

The Faraday dispersion function (FDF), which can be derived from an observed polarization spectrum by Faraday rotation measure synthesis, is a profile of polarized emissions as a function of Faraday depth. We study intrinsic FDFs along sight lines through face-on Milky Way like galaxies by means of a sophisticated galactic model incorporating three-dimensional MHD turbulence, and investigate how much information the FDF intrinsically contains. Since the FDF reflects distributions of thermal and cosmic-ray electrons as well as magnetic fields, it has been expected that the FDF could be a new probe to examine internal structures of galaxies. We, however, find that an intrinsic FDF along a sight line through a galaxy is very complicated, depending significantly on actual configurations of turbulence. We perform 800 realizations of turbulence and find no universal shape of the FDF even if we fix the global parameters of the model. We calculate the probability distribution functions of the standard deviation, skewness, and kurtosis of FDFs and compare them for models with different global parameters. Our models predict that the presence of vertical magnetic fields and the large-scale height of cosmic-ray electrons tend to make the standard deviation relatively large. In contrast, the differences in skewness and kurtosis are relatively less significant.open0

Primordial magnetic fields generated by the non-adiabatic fluctuations at pre-recombination era

In the pre-recombination era, cosmological density fluctuations can naturally generate magnetic fields through Thomson scatterings. In previous studies, only the magnetic field generation from the initially-adiabatic fluctuations has been considered. Here we investigate the generation of cosmological magnetic fields sourced by the primordial non-adiabatic fluctuations based on the cosmological perturbation theory, using the tight-coupling approximations between photon and baryon fluids. It is found that the magnetic fields from the non-adiabatic fluctuations can arise at the first-order expansion of the tight coupling approximation. This result is in contrast to the case of adiabatic initial fluctuations, where the magnetic fields can be generated only at the second-order. In a general case where the primordial density perturbations contain small non-adiabatic fluctuations on the top of the dominant adiabatic ones, we show that the leading source of magnetic fields is given by the second-order coupling of the adiabatic and non-adiabatic fluctuations. We calculate the power spectrum of the generated magnetic fields when the non-adiabatic fluctuations have a blue power spectrum, which has been suggested by recent cosmological observations.Comment: 16 pages, 2 figures, minor corrections, references added, to be published in JCA

Development of NIR Bioimaging Systems

Abstract. Fluorescence bioimaging is one of the most important technologies in the biomedical field. The most serious issue concerning current fluorescence bioimaging systems is the use of short wavelength light, UV or VIS, for the excitation of phosphors such as fluorescent proteins or quantum dots. The authors propose a fluorescence bioimaging system excited by near infrared light using rare-earth doped ceramic nanophosphors. The requirements for the nanophosphors are a designed emission scheme under the near infrared excitation, a controlled size between 10 and 200 nm and surface modification of the particles with a biofunctional polymer, which prevents particle agglomeration and non-specific interaction to nontargeting substances and gives them a specific interaction for the targeted objects. The preparation of the bioimaging probe and demonstrative imaging work are reported

The Surgical Benefits of Repeat Hepatectomy for Colorectal Liver Metastasis

The most common site of distant metastasis from colorectal cancer is the liver, and hepatectomy presents the best curative treatment for recurrence of colorectal liver metastasis （CRLM）. This study aimed to identify factors of prognostic value for repeat hepatectomy for CRLM and to determine whether a third such procedure could similarly produce favourable outcomes for CRLM. We analyzed data for 161 patients in our department with colorectal metastasis. Of these, 22 patients underwent repeat hepatectomy for recurrent metastasis, with 16 undergoing a second hepatectomy and 6 a third hepatectomy. We analyzed patient characteristics, tumor status, operation-related variables, and short- and long-term outcomes. Univariate analysis for repeat hepatectomy identified the following five prognostic risk factors: T factor （＞SE） of the primary cancer, number of tumors involved in the initial hepatectomy （＞5）, interval from first to second hepatectomy （＜1year）, number of tumors involved in second hepatectomy （＞3）, and post-operation time （＞30days）. By multivariate analysis, T factor （＞SE） of the primary cancer, number of tumors in the initial hepatectomy （＞5）, and number of tumors in the second hepatectomy （＞3） were independently associated with a worse survival after surgery for CRLM. Although surgical outcomes of the third hepatectomy were not compared with those of the first and second hepatectomy, there were no obvious differences, nor did the 1-, 3-, and 5-year survival rates differ significantly among the three groups. Repeat hepatectomy for CRLM could improve long-term survival. In addition, patients undergoing a third hepatectomy showed a similar survival benefit to those having one or two resections

Study of the Vertical Magnetic Field in Face-on Galaxies Using Faraday Tomography

Faraday tomography allows astronomers to probe the distribution of the magnetic field along the line of sight (LOS), but that can be achieved only after the Faraday spectrum is interpreted. However, the interpretation is not straightforward, mainly because the Faraday spectrum is complicated due to a turbulent magnetic field; it ruins the one-to-one relation between the Faraday depth and the physical depth, and appears as many small-scale features in the Faraday spectrum. In this paper, by employing &quot;simple toy models&quot; for the magnetic field, we describe numerically as well as analytically the characteristic properties of the Faraday spectrum. We show that the Faraday spectrum along &quot;multiple LOSs&quot; can be used to extract the global properties of the magnetic field. Specifically, considering face-on spiral galaxies and modeling turbulent magnetic field as a random field with a single coherence length, we numerically calculate the Faraday spectrum along a number of LOSs and its shape-characterizing parameters, that is, the moments. When multiple LOSs cover a region of greater than or similar to(10 coherence length) 2, the shape of the Faraday spectrum becomes smooth and the shape-characterizing parameters are well specified. With the Faraday spectrum constructed as a sum of Gaussian functions with different means and variances, we analytically show that the parameters are expressed in terms of the regular and turbulent components of the LOS magnetic field and the coherence length. We also consider the turbulent magnetic field modeled with a power-law spectrum, and study how the magnetic field is revealed in the Faraday spectrum. Our work suggests a way to obtain information on the magnetic field from a Faraday tomography study

The Japanese space gravitational wave antenna; DECIGO

DECi-hertz Interferometer Gravitational wave Observatory (DECIGO) is the future Japanese space gravitational wave antenna. DECIGO is expected to open a new window of observation for gravitational wave astronomy especially between 0.1 Hz and 10 Hz, revealing various mysteries of the universe such as dark energy, formation mechanism of supermassive black holes, and inflation of the universe. The pre-conceptual design of DECIGO consists of three drag-free spacecraft, whose relative displacements are measured by a differential Fabry– Perot Michelson interferometer. We plan to launch two missions, DECIGO pathfinder and pre- DECIGO first and finally DECIGO in 2024

DECIGO pathfinder

DECIGO pathfinder (DPF) is a milestone satellite mission for DECIGO (DECi-hertz Interferometer Gravitational wave Observatory) which is a future space gravitational wave antenna. DECIGO is expected to provide us fruitful insights into the universe, in particular about dark energy, a formation mechanism of supermassive black holes, and the inflation of the universe. Since DECIGO will be an extremely large mission which will formed by three drag-free spacecraft with 1000m separation, it is significant to gain the technical feasibility of DECIGO before its planned launch in 2024. Thus, we are planning to launch two milestone missions: DPF and pre-DECIGO. The conceptual design and current status of the first milestone mission, DPF, are reviewed in this article

The status of DECIGO

DECIGO (DECi-hertz Interferometer Gravitational wave Observatory) is the planned Japanese space gravitational wave antenna, aiming to detect gravitational waves from astrophysically and cosmologically significant sources mainly between 0.1 Hz and 10 Hz and thus to open a new window for gravitational wave astronomy and for the universe. DECIGO will consists of three drag-free spacecraft arranged in an equilateral triangle with 1000 km arm lengths whose relative displacements are measured by a differential Fabry-Perot interferometer, and four units of triangular Fabry-Perot interferometers are arranged on heliocentric orbit around the sun. DECIGO is vary ambitious mission, we plan to launch DECIGO in era of 2030s after precursor satellite mission, B-DECIGO. B-DECIGO is essentially smaller version of DECIGO: B-DECIGO consists of three spacecraft arranged in an triangle with 100 km arm lengths orbiting 2000 km above the surface of the earth. It is hoped that the launch date will be late 2020s for the present