Oxidative stress (OS) plays crucial roles in triethylene glycol dimethacrylate (TEGDMA, a major component in dental resin)-induced apoptosis of dental pulp cells. Mitochondria are important target ...organelles for regulating the balance of OS, meanwhile, imbalance of the mitochondrial dynamic associated with mitochondrial dysfunction is one major molecular mechanism for oxidative damages. However, whether these mitochondrial dependent pathways were involved in the apoptosis of dental pulp cells induced by TDGDMA remains unclarified. We demonstrated that TEGDMA decreased viability and induced apoptosis of mouse preodontoblasts (mDPC6T cell line) in a time- and dose-dependent manner. Furthermore, TEGDMA elevated the mitochondrial OS status and induced mitochondrial dysfunction, as reflected by the significant decrease of mitochondrial membrane potential, ATP production, the activity of Complex III and citrate synthase. In this process, we detected a dramatically impaired mitochondrial dynamic that was reflected by significantly enhanced mitochondrial fragmentation. Consistently, we also found a significant enhancement of the key upstream regulators for mitochondrial fission, such as short form of optic atrophy 1, dynamic related protein 1 oligomer and Fission 1. The respective inhibition of mitochondrial OS or mitochondrial fission could mutually attenuate each other, thereby significantly preventing both mitochondrial dysfunction and cell apoptosis. In conclusion, TEGDMA-induced preodontoblasts apoptosis was mediated by the vicious circle between mitochondrial OS and dynamic abnormality, which represented a new target to prevent TEGDMA-induced dental pulp cells apoptosis.
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•TEGDMA induced predontoblasts apoptosis through the mitochondrial intrinsic dependent pathways.•The virous circle between mitochondrial OS and dynamic abnormality contributed to TEGDMA induced mDPC6Ts apoptosis.•The study may provide a novel therapeutic strategy for prevention against resin-induced dental pulp damage.
Obstructive sleep apnoea (OSA) patients have a decreased exercise capacity. Potential cardiovascular capacity in patients with OSA with different severity without known cardiovascular disease has not ...been described.
To evaluate impaired potential exercise cardiovascular capacity during cardiopulmonary exercise testing (CPET) in OSA patients and to compare cardiovascular performance reaction with different severity during graded exercise stages.
All participants were accompanied without cardiovascular disease, especially hypertension and arrhythmia. Parameters of different stages were compared between subjects with and without OSA, and among OSA patients with varied severity.
Despite having significantly higher peak exercise diastolic blood pressure (DBP) and ventilatory equivalent for CO
(EQCO₂), patients with OSA had a lower peak oxygen uptake (VO₂), heart rate (HR), heart rate recovery (HRR) and respiratory reserve (BR) than normal subjects. Furthermore, significant correlations were found between VO₂, DBP, EQCO₂, HRR, BR and the apnoea-hypopnea index. In severe OSA, there was a greater difference in HR and HRR during the anaerobic threshold stages.
OSA patients demonstrate reduced potential cardiovascular capacity, even without documented cardiovascular disease. Patients with severe OSA develop impaired exercise capacity at early stage during exercise. These data point to exaggerated haemodynamic response to graded exercise and delayed post-exercise cardiovascular response recovery in OSA patients. CPET can be a supplement for assessment of OSA severity.
► Phytoplankton toxicity of chlortetracycline was examined first time. ► The toxicity of antibiotic UV-degraded products was also reported first time. ► The toxic effect on phytoplankton growth and ...photosynthesis function was compared.
Two common freshwater phytoplankton species Microcystis aeruginosa and Scenedesmus obliquus were employed as test organisms to investigate the toxic effects of chlortetracycline widely used in human medicine and veterinary as antibiotic. Toxicity assays were performed into two parts: antibiotic toxicity test and antibiotic degraded products toxicity test. In general, chlortetracycline had significantly toxic effect on population growth and chlorophyll-a accumulation of two phytoplankton. Although M. aeruginosa had ability to grow after exposed to chlortetracycline at 0.5mgL−1, its photosynthesis function was also disrupted. Compared with the data in two phytoplankton species, the chlorophyceae was more sensitive than the cyanophyceae. The adverse effect on S. obliquus was stronger than that on M. aeruginosa with increasing concentrations. In addition, for M. aeruginosa, regardless of the UV light degradation time, the treated chlortetracycline also had adverse effect on population growth and chlorophyll-a accumulated. The degraded chlortetracycline under any treatment time was more toxic for S. obliquus than chlortetracycline itself excluding under 24h. However, the correlation between the toxicity and degradation time was not clear and toxicity enhanced in fact did not follow the increase or decrease in degradation time. Our study showed that the antibiotic chlortetracycline and its degraded products had adverse effect on freshwater phytoplankton, the former has not been reported before and the latter has been overlooked in other research in the past.
Explaining Recollection Without Remembering Chen, X. R.; Gomes, C. F. A.; Brainerd, C. J.
Journal of experimental psychology. Learning, memory, and cognition,
12/2018, Letnik:
44, Številka:
12
Journal Article
Recenzirano
Odprti dostop
Recollection without remembering is a counterintuitive phenomenon that violates a traditional assumption of source memory models-namely, that accurate item memory is a necessary precondition for ...remembering source details that accompanied an item's presentation. The dual-recollection model explains recollection without remembering as a by-product of the contrasting effects of target and context recollection on item tests versus source tests. We pitted that explanation against 2 others that preserve the traditional assumption, one based on hypothesized testing artifacts and the other derived from multivariate signal detection theory. Our experiments focused on a manipulation that, according to dual-recollection theory, should drive source memory and item memory in opposite directions. In 2 experiments, studied items were tagged with 3 source details (voice gender, taxonomic category, and list), such that either (a) the 3 details were consistent with each other or (b) 1 detail was inconsistent with the other 2. As predicted, source memory was better but item memory was worse when source details were consistent with each other. The recollection without remembering effect was observed in both experiments, and as predicted by dual-recollection theory, it was more robust when item memory was worse than when it was better. A further instance of recollection without remembering was detected that involved distractors rather than presented items.
The timing and route of the earliest dispersal from Africa to Eastern Asia are contentious topics in the study of early human evolution because Asian hominin fossil sites with precise age constraints ...are very limited. Here we report new high-resolution magnetostratigraphic results that place stringent age controls on excavated hominin incisors and stone tools from the Yuanmou Basin, southwest China. The hominin-bearing layer resides in a reverse polarity magnetozone just above the upper boundary of the Olduvai subchron, yielding an estimated age of 1.7
Ma. The finding represents the age of the earliest documented presence of
Homo, with affinities to
Homo erectus, in mainland East Asia. This age estimate is roughly the same as for
H. erectus in island Southeast Asia and immediately prior to the oldest archaeological evidence in northeast Asia. Mammalian fauna and pollen obtained directly from the hominin site indicate that the Yuanmou hominins lived in a varied habitat of open vegetation with patches of bushland and forest on an alluvial fan close to a lake or swamp. The age and location are consistent with a rapid southern migration route of initial hominin populations into Eastern Asia.
We study electron behavior in the outer radiation belts during the 16 July 2017 storm sudden commencement (SSC), in which prompt intensification of ultrarelativistic electron fluxes was observed at ...around L = 4.8 by Van Allen Probe B immediately after an interplanetary shock. The electron fluxes in multiple energy channels show clear oscillations in the Pc5 frequency range, although the oscillation characteristics are quite different in different energy channels. At energies above ∼1 MeV, the oscillation periods were very close to the electron drift period, which resembles an energy spectrogram evolution expected for an energetic particle injection event and its drift echoes. At lower energies, however, the oscillation periods hardly depended on the energy: They were very close to the ultralow frequency (ULF) wave period derived from electric field measurements (about 250 s according to wavelet analysis). These complex signatures are consistent with the picture of drift resonance between electrons and short‐lived ULF waves with low azimuthal wave numbers. Good agreement between the observations and numerical simulations confirms that shock‐induced global‐scale ULF waves can efficiently accelerate outer belt ultrarelativistic electrons up to 3.4 MeV over a time scale shorter than 1 hr.
Key Points
The flux of ultrarelativistic electrons enhanced by an order of magnitude within 1 hr after SSC on 16 July 2017
Drift resonance between 3.4‐MeV electrons and shock‐induced ULF waves is confirmed
The behavior of nonresonant particles in response to the shock indicates the scenario of drift resonance with damping ULF waves
The activation of hepatic stellate cells (HSCs) is the key event of the pathogenesis of hepatic fibrosis. Platelet-derived growth factor (PDGF) is the most potent mitogen for HSCs, and PDGF ...receptor-beta subunit (PDGFR-beta) is required for the proliferation of HSCs induced by PDGF. In this study, a high gene-silencing-efficacy PDGFR-beta small interference RNA (siRNA) was synthesized that could suppress the PDGFR-beta expression and inhibit the activation and proliferation but could not induce the apoptosis of HSCs in vitro. To avoid the side effect of nonspecific interference of PDGFR-beta, we constructed an HSCs-specific short hairpin RNA (shRNA) expression plasmid in which PDGFR-beta shRNA was driven by a glial fibrillary acidic protein (GFAP) promoter. The double-staining immunofluorescence examination indicated that GFAP promoter could target the transgene expression into HSCs in carbon tetrachloride induced acute injured rat's liver and bile duct ligation (BDL)-induced chronic injured rat's liver. Furthermore, HSCs-specific PDGFR-beta shRNA could relieve liver injury and hepatic fibrosis in the rat's model induced by BDL. This study demonstrates that PDGFR-beta siRNA may be presented as an antifibrogenic agent. The application of HSCs-specific RNA interference induced by the GFAP promoter might supply a new powerful tool for cell-specific gene therapy of hepatic fibrogenesis.
Absolute calibration of LHAASO WFCTA camera based on LED An, Q.; Bai, Y.X.; Bastieri, D. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
01/2022, Letnik:
1021
Journal Article
Recenzirano
The main scientific goal of the LHAASO WFCTA experiment is to measure the cosmic ray energy spectra and composition from 10 TeV to 1 EeV. Cherenkov photons in the extensive air shower measured by the ...SiPM camera of Cherenkov telescopes can be used to reconstruct the cosmic ray energy. The absolute calibration of the camera is a crucial step to achieve the accurate measurement of the cosmic ray energy spectrum. A multi-wavelength cylindrical illuminator based on LEDs is developed and mounted inside the telescope to calibrate and monitor the camera, and the illuminator’s stability is better than 0.5% under the temperature variation from -26 to 26 °C. A portable probe with a single photoelectron resolution of 21.6% is developed. After calibration by National Institute of Metrology, China (NIM), the probe is taken to the LHAASO site to measure the absolute photon density of the cylindrical illuminator inside the telescope. Based on the illuminator with known photon density, the photon conversion factor of the camera can be calibrated, and the overall calibration uncertainty is less than 2.6%.
Resident stem cell pools in many tissues/organs are responsible not only for tissue maintenance during physiologic turnover but also for the process of wound repair following injury. With inspiration ...from stem cell trafficking within the body under physiologic and pathologic conditions, recent advances have been made toward inducing stem cell mobilization and directing patients’ own cells to sites of interest for treating a broad spectrum of diseases. An evolving body of work corroborates that delivering guidance cues can mobilize stem cells from the bone marrow and drive these cells toward a specific region. In addition, the transplantation of cell-friendly biomaterials incorporating certain biomolecules has led to the regeneration of lost/damaged tissue without the need for delivering cellular materials manipulated ex vivo. Recently, cell homing has resulted in remarkable biological discoveries in the laboratory as well as great curative successes in preclinical scenarios. Here, we review the biological evidence underlying in vivo cell mobilization and homing with the aim of leveraging endogenous reparative cells for therapeutic applications. Considering both the promise and the obstacles of this approach, we discuss how matrix components of the in vivo milieu can be modified to promote the native regenerative process and inspire future tissue-engineering design.
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