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The Near-Earth Asteroid 162173 Ryugu (1999 JU3) was investigated by the JAXA Hayabusa2 mission from June 2018 to November 2019. The data acquired by NIRS3 spectrometer revealed a dark surface with a positive near-infrared spectral slope. In this work we investigated the spectral slope variations across the Ryugu surface, providing information about physical/chemical properties of the surface. We analysed the calibrated, thermally and photometrically corrected NIRS3 data, and we evaluated the spectral slope between 1.9 μm and 2.5 μm, whose values extend from 0.11 to 0.28 and the mean value corresponds to 0.163±0.022. Starting from the mean value of slope and moving in step of 1 standard deviation (0.022), we defined 9 “slope families”, the Low-Red-Slope families (LR1, LR2 and LR3) and the High-Red-Sloped families (HR1, HR2, HR3, HR4, HR5, HR6). The mean values of some spectral parameters were estimated for each family, such as the reflectance factor at 1.9 μm, the spectral slope, the depth of bands at 2.7 μm and at 2.8 μm. A progressive spectral reddening, darkening and weakening/narrowing of OH bands is observed moving from the LR families to the HR families. We concluded that the spectral variability observed among families is the result of the thermal metamorphism experienced by Ryugu after the catastrophic disruption of its parent body and space weathering processes that occurred on airless bodies as Ryugu, such as impact cratering and solar wind irradiation. As a consequence, the HR1, LR1, LR2 and LR3 families, corresponding to equatorial ridge and crater rims, are the less altered regions on Ryugu surface, which experienced the minor alteration and OH devolatilization; the HR2, HR3, HR4, HR5 families, coincident with floors and walls of impact craters, are the most altered areas, result of the three processes occurring on Ryugu. The strong reddening of the HR6 family (coincident with Ejima Saxum) is likely due to the fine-sized material covering the large boulder.

The combination of cysteine-specific modifiers, iodoacetanilide (IAA) and (13)C7-labeled iodoacetanilide ((13)C7-IAA), has been applied to absolute quantification of proteins. The selected reaction monitoring (SRM) with the use of nano liquid chromatography/nanoelectrospray ionization ion trap mass spectrometry (nano LC/nano-ESI-IT-MS) analysis was applied to precise quantification of three commercial proteins. Good correlation was observed between the theoretical ratios and observed ratios for all these proteins both in a simple buffer solution and in a complex protein environment. Due to efficient tagging, this method does not require separate synthesis of isotope-labeled peptides for the SRM studies. Therefore, this method is expected to be a useful tool for proteomics research.

Objective We developed a new volume rendering technique, the CT gastrography wall carving image (WC) technique, which provides a clear visualization of localized enhanced tumors in the gastric wall. We evaluated the diagnostic performance of the WC as an adjunct to conventional images in detecting early gastric cancer (EGC). Materials and methods Thirty-nine patients with 43 EGCs underwent contrast-enhanced MDCT gastrography for preoperative examination. Two observers independently reviewed the images under three different conditions: term 1 , Axial CT; term 2 , Axial CT, MPR and VE; and term 3 , Axial CT, MPR, VE and WC for the detection of EGC. The accuracy of each condition as reviewed by each of the two observers was evaluated by receiver operating characteristic analysis. Interobserver agreement was calculated using weighted- κ statistics. Results The best diagnostic performance and interobserver agreement were obtained in term 3 . The AUCs of the two observers for terms 1, 2, and 3 were 0.63, 0.73, and 0.84, and 0.57, 0.73, and 0.76, respectively. The interobserver agreement improved from fair at term 1 to substantial at term 3 . Conclusions The addition of WC to conventional MDCT display improved the diagnostic accuracy and interobserver reproducibility for the detection of ECG. WC represents a suitable alternative for the visualization of localized enhanced tumors in the gastric wall.

Amphiregulin (AREG), an EGF family protein, is synthesized as a type I transmembrane precursor (proAREG) and expressed on the cell surface with an extracellular EGF-like domain and an intracellular short cytoplasmic tail. The ectodomain shedding yields a soluble EGF receptor ligand (soluble AREG) which binds to EGF receptor (EGFR) and concomitantly induces migration of unshed proAREG from the plasma membrane to the nuclear envelope (NE). AREG is known to play a potential role in breast cancer and has been intensively investigated as an EGF receptor ligand, while the function of the NE-localized proAREG remains unknown. In this study we used a truncated mutant that mimics NE-localized proAREG without shedding stimuli to discriminate between the functions of NE-localized and plasma membrane-localized proAREG and demonstrate that NE-localized proAREG activates breast cancer cell migration, but suppresses cell growth. Moreover, the present study shows that induction of cell migration by NE-localized proAREG does not require the extracellular growth factor domain or EGF receptor function. Collectively these data demonstrate a novel function mediated by the intracellular domain of proAREG and suggest a significant role for NE-localized proAREG in driving human breast cancer progression.

The aim is to evaluate if a difference in activity of monocytic cells can be described on superparamagnetic iron oxide (SPIO)-magnetic resonance imaging (MRI) in vitro when a low concentration of SPIO is administered. Human monocytic cells were stimulated with phorbol 12-myristate 13-acetate (PMA) or left non-stimulated for 24 h and then treated with SPIO with a final concentration of 7.2 microg Fe/ml for 48 h. They were collected, and an MRI phantom was prepared by suspending them in 4% gelatin and scanned using gradient-echo T2*-weighted and spin-echo T2-weighted imaging with two different echo times. The signal intensity and T2*/T2 relaxation times of each layer were also assessed. The number and degree of intracellular filling of cells positively stained with Berlin blue were evaluated microscopically. In addition, the heme oxygenase-1 expression in non-stimulated monocytic cells or monocytic cells stimulated with PMA was evaluated using semiquantitative reverse transcription and polymerase chain reaction. The signal reduction of cells stimulated with PMA was 3.9- to 5.0-fold and 2.7- to 3.1-fold greater than that of non-stimulated cells on the T2*- and T2-weighted images, respectively. These signal reductions were also visually confirmed. Estimated T2*/T2 relaxation times of cells stimulated with PMA and non-stimulated cells were 31.3/137.8 and 122.8/182.6 ms, respectively. Cells positively stained with Berlin blue were observed in 4.5% and 25.3% of non-stimulated cells and those stimulated with PMA, respectively (p

In this paper, we report 30 THz measurements of ammonia in its excited, ν2 = 1, inversion state. These measurements include transition frequencies and pressure shifts (where significant enough to be observed). Included in the data are two forbidden and three ro-inversion transitions, as well as 18 transitions never directly measured before. The measurements were made with an all-solid-state, diode-laser, difference-frequency spectrometer. Using an innovative laser-frequency locking scheme, this spectrometer provided accurately determined and continuously tuned THz-frequencies without requiring accurate knowledge of the absolute laser frequencies. The details of the spectrometer’s frequency calibration is discussed. A global analysis of NH3 based on the available ground state, ν2 = 1 state, and ν2-band transitions was carried out, and the resulting set of recommended molecular effective-Hamiltonian parameters for ammonia is presented. In addition, calculated center frequencies and intensities for all possible transitions up to J = 20 between rotation, inversion, and vibration levels in the ground and ν2 = 1 states are included as supplementary material .

We present a case of pulmonary metastasis from pancreatic cancer with biphasic radiological patterns: demarcated nodules, irregularly shaped opacities showing the so-called ‘air-space pattern’, and both typical and atypical radiological findings. The histology of the demarcated nodules was poorly differentiated adenocarcinoma identical to the pancreatic tumor, while that of the irregularly shaped opacities was well-differentiated adenocarcinoma showing a lepidic growth pattern. Pulmonary metastasis from pancreatic cancer may contain components of various differentiations showing different radiological findings.

Laminin gamma 2 chain is an extracellular matrix protein that plays an important role in cell migration and tumor invasion. We report altered expression and characteristic localization of this chain in a series of 105 cases of intrahepatic cholangiocarcinomas examined immunohistochemically. All tumors were grossly classified into the following three types: intraductal growth type (n=9), periductal infiltrating type (n=8) and mass-forming type (n=88). The tumors exhibited three distinct staining types: basement membrane staining, cytoplasmic staining and stromal staining. The basement membranous staining of laminin gamma 2 chain was more frequent in biliary dysplasia, intraductal growth and periductal infiltrating type than in mass-forming type. The cytoplasmic staining of carcinoma cells was observed especially at the cancer-stromal interface or at the invasive front of tumors. Stromal staining of laminin gamma 2 chain was essentially localized in the stroma around cancer cells at the invasive area, and the expression was significantly correlated with tumor aggressive factors and a poor prognosis in patients with intrahepatic cholangiocarcinoma. We conclude that laminin gamma 2 chain exhibits aberrant expression in a stepwise manner through different aggressive stages of tumor progression.

Tenascin and decorin are components of the extracellular matrix (ECM) that are implicated in cell proliferation in tumors. Here, we propose that abnormal expression of stromal ECM may play an important role in the progression of intrahepatic cholangiocarcinoma, which is characterized by desmoplastic reaction. To explore this hypothesis, we performed immunohistochemical analysis in order to examine the expression and distribution of tenascin and decorin in 75 cases of intrahepatic cholangiocarcinoma. In the intratumoral stroma, positive staining for tenascin was observed in 51 (68%) cases, and positive staining for decorin was observed in 61 (81%) cases. However, at the invasive front, positive staining for tenascin was found in 23 (31%) cases, and positive staining for decorin was found in 6 (8%) cases. Decorin staining was not correlated with aggressive behavior of intrahepatic cholangiocarcinoma, whereas intratumoral tenascin staining was correlated with lymphatic permeation and proliferative activity measured by Ki67. Tenascin staining at the invasive front was associated with tumor size, lymphatic permeation, lymph node metastasis, and proliferative activity and appeared to be a useful prognostic factor by univariate analysis, although it was not an independent prognostic factor. These results indicate that tenascin plays a role in tumor progression in cases of intrahepatic cholangiocarcinoma and that tenascin expression, especially at the invasive front, may be a useful marker in evaluating an unfavorable prognosis in patients with intrahepatic cholangiocarcinoma.

Background : Lens culinaris agglutinin (LCA)-reactive α-fetoprotein (AFP-L3) percentage of total AFP concentration [(AFP-L3/total AFP)×100] has been used as an effective marker for earlier diagnosis, for assessment of therapeutic effects and for predicting the prognosis of hepatocellular carcinoma (HCC). Methods : A new clinical automatic analyzer, the “LiBASys”, and an assay kit for the simultaneous determination of AFP-L3 percentage and concentration of AFP in human serum were developed. LiBASys performed automatic re-measurement and also met stat samples. Both AFP-L3 percentage and AFP concentration were calculated simultaneously and printed out continuously every 3.4 min per test. Results : A linear dose–response relationship was observed up to 1000 ng/ml AFP concentration. The detection limit and functional sensitivity of LCA-nonreactive AFP (AFP-L1) and AFP-L3 concentrations were 0.4 and 0.8 ng/ml, and 0.4 and 1.0 ng/ml, respectively. Interassay CVs of AFP-L3 percentage and AFP concentration ranged from 2.8% to 13.4% and 2.6% to 4.6%, respectively. Assay results exhibited good correlations with those of commercially available lectin-affinity electrophoresis ( r =0.984) for AFP-L3 percentage and with the RIA method ( r =0.999) for AFP concentration. Conclusions : This method simultaneously yields both qualitative and quantitative results for AFP-L3 percentage and AFP concentration.

This paper concerns self-assembled ErAs islands in GaAs grown by molecular beam epitaxy. The nucleation of ErAs on GaAs occurs in an island growth mode leading to spontaneous formation of nanometer-sized islands. Pump–probe measurements indicate that the ErAs islands capture photogenerated carriers on a subpicosecond time scale. This together with the high resitivity of the material allows us to use it as a fast photoconductor. The performance of photomixer devices made from this material is discussed.

Serum alpha-fetoprotein (AFP) is a glycoprotein of which the sugar chain is considered to show structural changes with malignancies. Microheterogeneity of the serum AFP carbohydrate structure was studied in samples from 35 patients with benign and malignant diseases. Sera were digested directly, extensively, and sequentially with sialidase. beta-galactosidase and beta-N-acetylhexosaminidase. Before and after digestion, sera were examined by means of lectin affinity electrophoresis using eight lectins. Relationships between AFP carbohydrate structures and liver diseases were elucidated by the lectin-reactive profiles and the effect of glycosidase digestion. More than 94% of the AFP carbohydrate structures found in patients with benign and malignant liver diseases were biantennary complex-type oligosaccharides. Changes in the AFP carbohydrate structures at the early stage of hepatocellular carcinoma revealed the addition of alpha 1-->6 fucose to the reducing terminal N-acetylglucosamine and monosialylated AFPs. In both advanced hepatocellular carcinoma and AFP producing extrahepatic malignancies, AFP carbohydrate structures were characterized as the further addition of beta 1-->4 N-acetylglucosamine and heterogeneity in the galactose and N-acetylglucosamine residues. Sequential glycosidase digestion and lectin affinity electrophoresis is useful for analysing the carbohydrate structures of serum glycoprotein.

Our recent rocket-borne observations have provided valuable information on the near-infrared feature of the zodiacal light at high ecliptic latitude and large solar elongation. The observed spectra at λ

The EPR study of cytochrome c in which FE(III) ion is replaced with Cu(II) shows that there are two types of monomer (a: 4 less than pH less than 6, and b: 6 less than pH less than 11.5) and two types of dimer (A: pH less than 4 and B: pH less than 11.5) formed depending upon the pH value of the solution. Computer simulation of the EPR spectra of the dimers indicates that the structure of the dimer A has a larger lateral shift than in the dimer B. It is also shown that in monomer a, the imidazole nitrogen of 18-His is not bound to Cu(II), while it is bound in the monomer b. In the undeca- and octapeptide of Cu(II)-cytochrome c, polymers are formed in acidic solutions. As the pH is raised, depolymerization proceeds to yield the monomer and the dimer. The structure of the dimer in both peptides is found to be similar to that of the dimer B of Cu(II)-cytochrome c. In the monomer of the peptides, neither the imidazole of 18-His nor the imidazole added in excess is bound to Cu(II) in the entire pH range. It is also concluded that the dimerization in Cu(II)-porphyrins interferes with the apical coordination of basic ligand, or vice versa.

Advantage of cloning probe DNA fragment in phage M13 DNA was taken to provide a larger single stranded DNA as a hybridization probe. High level of direct enzyme labels was introduced via the M13 DNA moiety as well as probe DNA. A highly sensitive colorimetric detection of virus DNA and oncogene was developed.

Elution of gonadotropins and other glycoproteins from concanavalin A has been previously performed with competitive ligands such as α-methyl-d-mannopyranoside and α-methyl-d-glucopyranoside. In comparative studies we found that 1 m NH4OH was a highly effective eluent solution and gave nearly complete recovery of gonadotropin as revealed by protein contents, immunological, and biological activities. Advantages of 1 m NH4OH over the sugar derivatives are its low cost and volatile nature, and its ability to irreversibly inactivate concanavalin A. The use of this system permits further steps of purification to be performed directly or after lyophilization without dialysis.