152 research outputs found
PKR is necessary for osteoclastogenesis.
Double-stranded RNA-dependent protein kinase (PKR) is involved in cell cycle progression, cell proliferation, cell differentiation, tumorgenesis, and apoptosis. We previously reported that PKR is required for differentiation and calcification in osteoblasts. TNF-α plays a key role in osteoclast differentiation. However, it is unknown about the roles of PKR in the TNF-α-induced osteoclast differentiation. The expression of PKR in osteoclast precursor RAW264.7 cells increased during TNF-α-induced osteoclastogenesis. The TNF-α-induced osteoclast differentiation in bone marrow-derived macrophages and RAW264.7 cells was markedly suppressed by the pre-treatment of PKR inhibitor, 2-aminopurine (2AP), as well as gene silencing of PKR. The expression of gene markers in the differentiated osteoclasts including TRAP, Calcitonin receptor, cathepsin K and ATP6V0d2 was also suppressed by the 2AP treatment. Bone resorption activity of TNF-α-induced osteoclasts was also supressed by 2AP treatment. Inhibition of PKR supressed the TNF-α-induced activation of NF-κB and MAPK in RAW264.7 cells. 2AP inhibited both the nuclear translocation of NF-κB and its transcriptional activity in RAW264.7 cells. 2AP inhibited the TNF-α-induced expression of NFATc1 and c-fos, master transcription factors in osteoclastogenesis. TNF-α-induced nuclear translocation of NFATc1 in mature osteoclasts was clearly inhibited by the 2AP treatment. The PKR inhibitor C16 decreased the TNF-α-induced osteoclast formation and bone resorption in mouse calvaria. The present study indicates that PKR is necessary for the TNF-α-induced osteoclast differentiation in vitro and in vivo
Terahertz wireless communication at 560-GHz band using Kerr micro-resonator soliton comb
Terahertz (THz) waves have attracted attention as carrier waves for
next-generation wireless communications (6G). Electronic THz emitters are
widely used in current mobile communications; however, they may face technical
limitations in 6G with upper-frequency limits. We demonstrate wireless
communication in a 560-GHz band by using a photonic THz emitter based on
photomixing of a 560-GHz-spacing soliton microcomb in a uni-travelling carrier
photodiode together with a THz receiver of Schottky barrier diode. The on-off
keying data transfer with 2-Gbit/s achieves a Q-factor of 3.4, thus, satisfying
the limit of forward error correction.Comment: 17 pages, 4 figur
Terahertz wireless communication in a 560-GHz band using a Kerr micro-resonator soliton comb
Terahertz (THz) waves have attracted attention as carrier waves for next-generation wireless communications (6 G). Electronic THz emitters are widely used in current mobile communications; however, they may face technical limitations in 6 G with upper-frequency limits. We demonstrate wireless communication in a 560-GHz band by using a photonic THz emitter based on photomixing of a 560-GHz-spacing soliton microcomb in a uni-travelling carrier photodiode together with a THz receiver of Schottky barrier diode. The on-off keying data transfer with 2-Gbit/s achieves a Q-factor of 3.4, thus, satisfying the limit of forward error correction
Host selection of hematophagous leeches (Haemadipsa japonica): Implications for iDNA studies
The development of an efficient and cost‐effective method for monitoring animal populations or biodiversity is urgently needed, and invertebrate‐derived DNA (iDNA) may offer a promising tool for assessing the diversity and other ecological information of vertebrates. We studied the host species of a hematophagous leech (Haemadipsa japonica) in Yakushima by genetic barcoding and compared the results with those for mammal composition revealed by camera trapping. We analyzed 119 samples using two sets of primers by Sanger sequencing and one set of primer by next generation sequencing. The proportion of the samples that were successfully sequenced and identified to at least one species was 11.8–24.3%, depending on the three different methods. In all of these three methods, most of the samples were identified as sika deer (18/20, 6/15 and 16/29) or human (2/20, 7/15 and 21/29). The nonhuman mammal host species composition was significantly different from that estimated by camera trapping. Sika deer was the main host, which may be related with their high abundance, large body size and terrestriality. Ten samples included DNA derived from multiple species of vertebrates. This may be due to the contamination of human DNA, but we also found DNA from deer, Japanese macaque and a frog in the same samples, suggesting the mixture of the two meals in the gut of the leech. Using H. japonica‐derived iDNA would not be suitable to make an inventory of species, but it may be useful to collect genetic information on the targeted species, due to their high host selectivity
Management of Acute Superior Mesenteric Artery Occlusion by Thrombolytic Therapy
Acute occlusion of the superior mesenteric artery (SMA) causes extensive bowel necrosis, resulting in a poor prognosis with an extremely high mortality rate. An 82-year-old woman was admitted to our hospital with the complaint of abdominal pain. She was diagnosed as having acute SMA occlusion by enhanced CT. Five hours from onset, the first thrombolytic therapy with urokinase was performed, but failed to complete thrombolysis and recanalization of peripheral blood flow. An exploratory laparotomy following the first thrombolytic therapy showed a mild ischemic change in the affected intestine and mesentery, but no sign of necrosis. After the laparotomy, local thrombolytic therapy with angiographic evaluation of blood flow at 24, 36 and 48 h from the first thrombolysis was performed. As a result, the residual thrombus disappeared and all branches of the SMA became well visualized. The patient was discharged well without a second-look operation or major bowel resection. Sequential intermittent thrombolytic therapy with meticulous angiographic evaluation of blood flow is effective for early-stage acute SMA occlusion
High sequence-coverage detection of proteolytic peptides using a bis(terpyridine)ruthenium(II) complex
Wireless data transmission in a 560-GHz band using low-phase-noise terahertz wave generated by photomixing of a pair of distributed feedback lasers injection-locking to Kerr micro-resonator soliton comb
The demand for higher data rates in next-generation mobile wireless
communication systems (6G) has led to significant interest in terahertz (THz)
waves as a high-frequency, broad modulation bandwidth carrier wave. In this
study, we propose and demonstrate a wireless data transfer in the 560-GHz band
using low-phase-noise THz waves generated by photomixing of a pair of
distributed feedback lasers injection-locking to Kerr micro-resonator soliton
comb. Experimental results showed near-error-free on-off keying (OOK) data
transfer at 1 Gbit/s in the 560-GHz band, with a Q-factor of 6.23, surpassing
the error-free limit. Also, modulation formats of binary phase shift keying
(BPSK) and quadrature phase shift keying (QPSK) were successfully used, showing
clear constellation diagrams and relatively low root mean squared error vector
magnitude (rms EVM) values of 23.9% and 23.6%, respectively. Moreover, data
transfer at 0.4 Gbit/s in 16 quadrature amplitude modulation (16QAM)
demonstrated clear isolated symbols and achieved a low rms EVM value of 8.1%,
complying with the IEEE 802.15.3d standard amendment. These demonstrations
highlight the potential of using injection-locked DFB lasers with the Kerr
micro-resonator soliton comb to achieve high-quality, high-speed wireless data
transfer in the 560-GHz band. These findings contribute significantly to the
advancement of wireless communication technology in the THz frequency range and
pave the way for the realization of 6G wireless communication systems
Carrier conversion from terahertz wave to dual-wavelength near-infrared light injection-locking to optical comb using asynchronous nonpolarimetric electro-optic downconversion with electro-optic polymer modulator
THz waves are promising wireless carriers for next-generation wireless
communications, where a seamless connection from wireless to optical
communication is required. In this study, we demonstrate carrier conversion
from THz waves to dual-wavelength NIR light injection-locking to an optical
frequency comb using asynchronous nonpolarimetric electro-optic downconversion
with an electro-optic polymer modulator. THz wave in the W band was obtained as
a stable photonic RF beat signal of 1 GHz with a signal-to-noise ratio of 25 dB
via the proposed THz-to-NIR carrier conversion. In addition, the results imply
the potential of the photonic detection of THz waves for wireless-to-optical
seamless communication.Comment: 15 pages, 5 figure
Psychiatric intervention and repeated admission to emergency centres due to drug overdose
Self-harm, with or without suicidal intent, substantially increases the risk of future suicide and is known to be the strongest predictor of completed suicide. Furthermore, repetition of self-harm is common: 16% of patients who self-harmed were found to repeat a similar episode within 1 year. Repetition of self-harm increases the risk of completed suicide. One study found overdose to be the most prevalent type of suicide attempt that required admission, and approximately 80% of self-harm episodes have been reported to involve overdose. It is therefore necessary to prevent the repetition of self-harm by drug overdose. According to clinical guidelines on the management of self-harm published in 2004, it is recommended that every patient presenting to hospital with self-harm should undergo a psychosocial assessment by specialists before being discharged. Despite this recommendation, some studies have found that many patients, especially those with repeated self-harm did not actually receive such assessments. That would suggest that the guideline has not been widely used – possibly because it was not based on firm evidence. There is a lack of data on the influence of psychosocial assessments on preventing repetition of self-harm. Some studies have suggested that such assessments do have an influence, but they were based on a small sample size or on a small number of highly advanced institutions. The present study focused on patients with drug overdose who were admitted to emergency centres. Using a national in-patient database in Japan, it aimed to investigate whether psychiatric intervention before discharge was associated with reduced patient readmissions with drug overdose.UTokyo Research掲載「過量服薬による入院患者と精神科医による診察の関係」 URI: http://www.u-tokyo.ac.jp/ja/utokyo-research/research-news/psychiatric-intervention-and-repeated-emergency-admission-due-to-drug-overdose.htmlUTokyo Research "Psychiatric intervention and repeated emergency admission due to drug overdose" URI: http://www.u-tokyo.ac.jp/en/utokyo-research/research-news/psychiatric-intervention-and-repeated-emergency-admission-due-to-drug-overdose.htm
Small-cell lung cancer with voltage-gated calcium channel antibody-positive paraneoplastic limbic encephalitis: a case report
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