159 research outputs found
Slowed response to peripheral visual stimuli during strenuous exercise
Recently, we proposed that strenuous exercise impairs peripheral visual perception because visual responses to peripheral visual stimuli were slowed during strenuous exercise. However, this proposal was challenged because strenuous exercise is also likely to affect the brain network underlying motor responses. The purpose of the current study was to resolve this issue. Fourteen participants performed a visual reaction-time (RT) task at rest and while exercising at 50% (moderate) and 75% (strenuous) peak oxygen uptake. Visual stimuli were randomly presented at different distances from fixation in two task conditions: the Central condition (2° or 5° from fixation) and the Peripheral condition (30° or 50° from fixation). We defined premotor time as the time between stimulus onset and the motor response, as determined using electromyographic recordings. In the Central condition, premotor time did not change during moderate (167 ± 19 ms) and strenuous (168 ± 24 ms) exercise from that at rest (164 ± 17 ms). In the Peripheral condition, premotor time significantly increased during moderate (181 ± 18 ms, P < 0.05) and strenuous exercise (189 ± 23 ms, P < 0.001) from that at rest (173 ± 17 ms). These results suggest that increases in Premotor Time to the peripheral visual stimuli did not result from an impaired motor-response network, but rather from impaired peripheral visual perception. We conclude that slowed response to peripheral visual stimuli during strenuous exercise primarily results from impaired visual perception of the periphery
Dilated Cardiomyopathy Risk in Patients with Coronavirus Disease 2019: How to Identify and Characterise it Early?
Multiple lines of evidence have shown that elevated blood troponin is strongly associated with poor prognosis in patients with the novel coronavirus disease 2019 (COVID-19). Possible mechanisms of myocardial injury in COVID-19 include ischaemia due to circulatory and respiratory failure, epicardial or intramyocardial small coronary artery thrombotic obstruction due to increased coagulability, and myocarditis caused by systemic inflammation or direct binding of the virus to its receptor, angiotensin-converting enzyme-2 (ACE2), which is abundantly expressed in the heart. It is postulated that persistent immune activation upon viral infection increases the risk of developing dilated cardiomyopathy in COVID-19 patients
Novel Approach to the Characterization of Melanoma Associated-Peptide-Specific CTL Lines from Melanoma Patients
Prebiotic treatment reduced preneoplastic lesions through the downregulation of toll like receptor 4 in a chemo-induced carcinogenic model
Germinated barley foodstuff contains prebiotics which are reported to have anti-cancerous effects in colorectal cancer model, but the detailed mechanism remains unclear. Recent studies revealed that the role of microbiota was strongly related to the regulation of incidence and progression of colorectal cancer. The aim of this study was to examine the anti-neoplastic mechanism by prebiotics. Azoxymethane treated F344 rats were used as the sporadic cancerous model. After azoxymethane injection, either a control or germinated barley foodstuff diet was administered to the rats for another 5 weeks, and the number of abberant crypt foci, toll like receptor 4, Kirsten rat sarcoma viral oncogene homolog, adenomatous polyposis coli tumor suppressor gene and cyclooxygenase 2 mRNA expression of colonic mucosa and cecal short chain fatty acids were examined. The germinated barley food stuff significantly attenuated the number of abberant crypt focis and the expression of toll like receptor 4 and cyclooxygenase 2 mRNA, compared to the control group. In addition, the cecal butyrate production in the germinated barley foodstuff group was significantly higher than that in the control. In conclusion, this prebiotic treatment for colorectal cancer may be useful without causing the adverse effects seen in either anti-cancer drugs or anti-inflammatory drugs
SILVERRUSH. III. Deep Optical and Near-Infrared Spectroscopy for Lya and UV-Nebular Lines of Bright Lya Emitters at z=6-7
We present Lya and UV-nebular emission line properties of bright Lya emitters
(LAEs) at z=6-7 with a luminosity of log L_Lya/[erg s-1] = 43-44 identified in
the 21-deg2 area of the SILVERRUSH early sample developed with the Subaru Hyper
Suprime-Cam (HSC) survey data. Our optical spectroscopy newly confirm 21 bright
LAEs with clear Lya emission, and contribute to make a spectroscopic sample of
96 LAEs at z=6-7 in SILVERRUSH. From the spectroscopic sample, we select 7
remarkable LAEs as bright as Himiko and CR7 objects, and perform deep
Keck/MOSFIRE and Subaru/nuMOIRCS near-infrared spectroscopy reaching the
3sigma-flux limit of ~ 2x10^{-18} erg s-1 for the UV-nebular emission lines of
He II1640, C IV1548,1550, and O III]1661,1666. Except for one tentative
detection of C IV, we find no strong UV-nebular lines down to the flux limit,
placing the upper limits of the rest-frame equivalent widths (EW_0) of ~2-4 A
for He II, C IV, and O III] lines. Here we also investigate the VLT/X-SHOOTER
spectrum of CR7 whose 6 sigma detection of He II is claimed by Sobral et al.
Although two individuals and the ESO-archive service carefully re-analyze the
X-SHOOTER data that are used in the study of Sobral et al., no He II signal of
CR7 is detected, supportive of weak UV-nebular lines of the bright LAEs even
for CR7. Spectral properties of these bright LAEs are thus clearly different
from those of faint dropouts at z~7 that have strong UV-nebular lines shown in
the various studies. Comparing these bright LAEs and the faint dropouts, we
find anti-correlations between the UV-nebular line EW_0 and UV-continuum
luminosity, which are similar to those found at z~2-3.Comment: 26 pages, 12 figures. Accepted for publication in PASJ special issu
SILVERRUSH. VII. Subaru/HSC Identifications of 42 Protocluster Candidates at z~6-7 with the Spectroscopic Redshifts up to z=6.574: Implications for Cosmic Reionization
We report fourteen and twenty-eight protocluster candidates at z=5.7 and 6.6
over 14 and 19 deg^2 areas, respectively, selected from 2,230 (259) Lya
emitters (LAEs) photometrically (spectroscopically) identified with
Subaru/Hyper Suprime-Cam (HSC) deep images (Keck, Subaru, and Magellan spectra
and the literature data). Six out of the 42 protocluster candidates include
1-12 spectroscopically confirmed LAEs at redshifts up to z=6.574. By the
comparisons with the cosmological Lya radiative transfer (RT) model reproducing
LAEs with the reionization effects, we find that more than a half of these
protocluster candidates are progenitors of the present-day clusters with a mass
of > 10^14 M_sun. We then investigate the correlation between LAE overdensity
delta and Lya rest-frame equivalent width EW_Lya^rest, because the cosmological
Lya RT model suggests that a slope of EW_Lya^rest-delta relation is steepened
towards the epoch of cosmic reionization (EoR), due to the existence of the
ionized bubbles around galaxy overdensities easing the escape of Lya emission
from the partly neutral intergalactic medium (IGM). The available HSC data
suggest that the slope of the EW_Lya^rest-delta correlation does not evolve
from the post-reionization epoch z=5.7 to the EoR z=6.6 beyond the moderately
large statistical errors. There is a possibility that we would detect the
evolution of the EW_Lya^rest - delta relation from z=5.7 to 7.3 by the upcoming
HSC observations providing large samples of LAEs at z=6.6-7.3
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