149 research outputs found
Calibration of the AKARI Far-Infrared Imaging Fourier Transform Spectrometer
The Far-Infrared Surveyor (FIS) onboard the AKARI satellite has a
spectroscopic capability provided by a Fourier transform spectrometer
(FIS-FTS). FIS-FTS is the first space-borne imaging FTS dedicated to
far-infrared astronomical observations. We describe the calibration process of
the FIS-FTS and discuss its accuracy and reliability. The calibration is based
on the observational data of bright astronomical sources as well as two
instrumental sources. We have compared the FIS-FTS spectra with the spectra
obtained from the Long Wavelength Spectrometer (LWS) of the Infrared Space
Observatory (ISO) having a similar spectral coverage. The present calibration
method accurately reproduces the spectra of several solar system objects having
a reliable spectral model. Under this condition the relative uncertainty of the
calibration of the continuum is estimated to be 15% for SW, 10% for
70-85 cm^(-1) of LW, and 20% for 60-70 cm^(-1) of LW; and the absolute
uncertainty is estimated to be +35/-55% for SW, +35/-55% for 70-85 cm^(-1) of
LW, and +40/-60% for 60-70 cm^(-1) of LW. These values are confirmed by
comparison with theoretical models and previous observations by the ISO/LWS.Comment: 22 pages, 10 figure
Coordinately Co-opted Multiple Transposable Elements Constitute an Enhancer for wnt5a Expression in the Mammalian Secondary Palate
Acquisition of cis-regulatory elements is a major driving force of evolution, and there are several examples of developmental enhancers derived from transposable elements (TEs). However, it remains unclear whether one enhancer element could have been produced via cooperation among multiple, yet distinct, TEs during evolution. Here we show that an evolutionarily conserved genomic region named AS3_9 comprises three TEs (AmnSINE1, X6b_DNA and MER117), inserted side-by-side, and functions as a distal enhancer for wnt5a expression during morphogenesis of the mammalian secondary palate. Functional analysis of each TE revealed step-by-step retroposition/transposition and co-option together with acquisition of a binding site for Msx1 for its full enhancer function during mammalian evolution. The present study provides a new perspective suggesting that a huge variety of TEs, in combination, could have accelerated the diversity of cis-regulatory elements involved in morphological evolution
A modified application of the luciferase immunoprecipitation systems for detecting antibodies to the G protein-coupled receptors
Background: When multipass transmembrane molecules are located on the cell surface, there may be interaction with notonly bioactive molecules but also pathogenic molecules in areas protruding outside the cell. In antibody-mediated autoimmunedisorders, it has been found that the autoantibodies occasionally attack membrane molecules on the cell surface, thus causingthe disease such as myasthenia gravis. In such cases, highly sensitive autoantibody detection technology is required for earlydiagnosis. However, autoantibody analysis technology that is specialized for membrane molecules is still under development.Here we demonstrate a novel method for detecting of antibodies against the extracellular portions of multipass transmembranemolecules.Methods: Antibodies for muscarinic acetylcholine receptor type3 (M3R) were detected with two kinds of luciferase immunoprecipitaionsystems (LIPS), conventional LIPS (cLIPS) and its modified application, termed modified LIPS (mLIPS). In mLIPS, antibodiesagainst extracellular portions of membrane molecules could be preferentially detected.Results: An antibody to the amino-terminal portion of human M3R was detected with modified LIPS with a high sensitivity. Incontrast, an antibody to the carboxyl-terminal portion was not detected with mLIPS, because it did not interact with intracellularportions of M3R in living cells. We also found antibodies for M3R in a patient serum with Sjogren’s syndrome.Conclusion: Our technology has a promising future, and we hope that it will be applied in the analysis of antibodies against adiverse range of multipass transmembrane molecules, including GPCRs
Effect of dietary fatty acid composition on Th1/Th2 polarization in lymphocytes.
BACKGROUND: It has become increasingly clear that polyunsaturated fatty acids (PUFAs) have immunomodulatory effects. However, the intake of these fatty acids used in animal studies often greatly exceeds dietary human intake. Whether differences in the composition of fatty acids that are consumed in amounts consistent with normal dietary intake can influence immune function remains uncertain. METHODS: We manufactured 3 types of liquid diet, related to modified fatty acid composition (omega-6/omega-3 = 0.25, 2.27 and 42.9), but excluding eicosapentaenoic acid and docosahexaenoic acid, based upon a liquid diet used clinically in humans. We assessed CD3-stimulated cytokine production of splenocytes in female BALB/c mice (n = 4 per group) fed 1 of 3 liquid diets for 4 weeks. We also measured the cytokine production of peripheral blood mononuclear cells stimulated with phorbol myristate acetate and ionomycin in humans at the end of a 4-week period of consumption of 2 different liquid diets (omega-6/omega-3 = 3 and 44). RESULTS: We found that the ratio of interfero omega-gamma (IFN-gamma) / interleukin-4 (IL-4) was significantly higher in mice fed the omega-3 rich diet than in others. In humans, IFN-gamma / IL-4 was significantly higher after the omega-3 versus the omega-6 enhanced diet. CONCLUSIONS: Differences in the composition of omega-3 and omega-6 PUFAs induces a shift in the Th1/Th2 balance in both mouse and human lymphocytes, even when ingested in normal dietary amounts. An omega-3 rich diet containing alpha-linolenic acid modulates immune function
Performance of the Imaging Fourier Transform Spectrometer with Photoconductive Detector Arrays: An Application for the AKARI Far-Infrared Instrument
We have developed an imaging Fourier transform spectrometer (FTS) for
space-based far-infrared astronomical observations. The FTS employs a newly
developed photoconductive detector arrays with a capacitive trans-impedance
amplifier, which makes the FTS a completely unique instrument. The FTS was
installed as a function of the far-infrared instrument (FIS: Far-Infrared
Surveyor) on the Japanese astronomical satellite, AKARI, which was launched on
February 21, 2006 (UT) from the Uchinoura Space Center. The FIS-FTS had been
operated for more than one year before liquid helium ran out on August 26,
2007. The FIS-FTS was operated nearly six hundreds times, which corresponds to
more than one hundred hours of astronomical observations and almost the same
amount of time for calibrations. As expected from laboratory measurements, the
FIS-FTS performed well and has produced a large set of astronomical data for
valuable objects. Meanwhile, it becomes clear that the detector transient
effect is a considerable factor for FTSs with photoconductive detectors. In
this paper, the instrumentation of the FIS-FTS and interesting phenomena
related to FTS using photoconductive detectors are described, and future
applications of this kind of FTS system are discussed.Comment: 10 pages, 6 figures, 2 tables, accepted for publication in PASJ AKARI
special issu
Detecting gastrointestinal manifestations in patients with systemic sclerosis using anti-gAChR antibodies
Background: Patients with systemic sclerosis (SSc) complicated by gastrointestinal dysmotility are difficult to treat and have high mortality. To clarify the pathogenesis of gastrointestinal manifestations, we aimed to demonstrate the association among the clinical features of SSc, the serological markers, the autoantibodies against nicotinic acetylcholine receptor at autonomic ganglia (gAChR). Methods: Fifty patients were enrolled and divided into two groups according to the presence or absence of gastrointestinal manifestations, and the characteristics were analyzed between these two groups. We measured biomarkers and the autoantibodies against two gAChRα3 and β4 subunits to test sera samples. Furthermore, patients were classified based on the presence or absence of anti-gAChR autoantibodies, and their clinical features were compared. Results: In patients with SSc and gastrointestinal manifestations, digital ulcers were more frequent (p = 0.050) and VEGF expression was significantly higher (p = 0.038). Seven subjects with SSc were seropositive for α3 subunit, whereas one patient was seropositive for β4 subunit. The mean level of anti-gAChRα3 autoantibodies in SSc patients with gastrointestinal manifestations was significantly higher than that in SSc patients without gastrointestinal manifestations (p = 0.001). The group of patients with SSc and gAChR autoantibodies had significantly higher endostatin levels (p = 0.046). Conclusions: This study is the first to demonstrate that clinical characteristics of SSc patients with seropositivity for gAChR autoantibodies. Patients with SSc have circulating autoantibodies against gAChR, which may contribute to gastrointestinal manifestations associated with this disease, suggesting that gAChR-mediated autonomic neurotransmission may provide a pathomechanism for gastrointestinal dysmotility in SSc
Endometriosis of the ileum treated by laparoscopic ileocecal resection
A 29-year-old female was admitted due to abdominal pain. Abdominal computed tomography showed a tumor in terminal ileum and expanded jejunum, and colonoscopy showed a collection of lymph follicles. Biopsy finding showed a lymphoid tissue hyperplasia and no malignant finding. Therefore, we performed a laparoscopic ileocecal resection for diagnosis and treatment. Histopathological findings showed endometrial tissue in the muscular layer, and we diagnosed endometriosis of ileum. We performed a laparoscopic ileocecal resection with lymph node dissection, because the possibility of malignant tumor could not be ruled out. Laparoscopic operation is useful for the diagnosis and treatment of intestinal endometriosis, because it prevents the adhesion and abdominal wall destruction possibly
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