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Neuronal pyroptosis serves an important role in the progress of neurologic dysfunction following subarachnoid hemorrhage (SAH), which is predominantly caused by a ruptured aneurysm. Hydrogen gas has been previously reported to be an effective anti-inflammatory agent against ischemia-associated diseases by regulating mitochondrial function. The objective of the present study was to investigate the potential neuroprotective effects of hydrogen gas post-conditioning against neuronal pyroptosis after SAH, with specific focus on the mitochondrial ATP-sensitive K+ (mitoKATP) channels. Following SAH induction by endovascular perforation, rats were treated with inhalation of 2.9% hydrogen gas for 2 h post-perforation. Neurologic deficits, brain water content, reactive oxygen species (ROS) levels, neuronal pyroptosis, phosphorylation of ERK1/2, p38 MAPK and pyroptosis-associated proteins IL-1β and IL-18 were evaluated 24 h after perforation by a modified Garcia method, ratio of wet/dry weight, 2',7'-dichlorofluorescin diacetate, immunofluorescence and western blot assays, respectively. An inhibitor of the mitoKATP channel, 5-hydroxydecanoate sodium (5-HD), was used to assess the potential role of the mitoKATP-ERK1/2-p38 MAPK signal pathway. Hydrogen gas post-conditioning significantly alleviated brain edema and improved neurologic function, reduced ROS production and neuronal pyroptosis, suppressed the expression of IL-1β and IL-18 whilst upregulating ERK1/2 phosphorylation, but downregulated p38 MAPK activation 24 h post-SAH. These aforementioned effects neuroprotective were partially reversed by 5-HD treatment. Therefore, these observations suggest that post-conditioning with hydrogen gas ameliorated SAH-induced neuronal pyroptosis at least in part through the mitoKATP/ERK1/2/p38 MAPK signaling pathway. [ABSTRACT FROM AUTHOR]

Through several groups of large scale(300 mmx300 mmx300 mm)true tri-axial tests, influences of ground stress, natural cleat or fracture, interlayer and interface's property on hydraulic fractures' propagation and geometry in coal samples deprived from the south of Qinshui Basin were studied. The test results show that developed natural cleat or fracture in coal-bed results in high pumping pressure with frequent fluctuation when fracturing, and hydraulic fractures' propagation remains unsteady with complicated geometry. When horizontal stress difference is small, hydraulic fractures can start to occur along multi-direction, usually forming multi-fracture system during propagation, and hydraulic fractures can propagate along cleat and natural fractures randomly. With the horizontal stress difference increasing, hydraulic fractures tend to happen along the vertical direction of minimum horizontal stress with relative simple geometry. The function of physical property difference between coal-bed and interlayer in controlling hydraulic fractures' interface crossing is not remarkable. However, vertical compressive stress on the interlayer and interface property are the main elements to determine whether the hydraulic fractures can cross the interface into interlayer. In the situation of low vertical stress, low interface's cementing strength and correspondingly small friction coefficient, hydraulic fractures can glide transversally along the interface, but can not cross the interface into the interlayer. On the contrary, hydraulic fractures can easily cross the interface into interlayer. [ABSTRACT FROM AUTHOR]

Aim: To describe the characteristics of modulation transfer function (MTF) of anterior corneal surface, and obtain the the normal reference range of MTF at different spatial frequencies and optical zones of the anterior corneal surface in myopes., Methods: Four hundred eyes from 200 patients were examined under SIRIUS corneal topography system. Phoenis analysis software was applied to simulate the MTF curves of anterior corneal surface at vertical and horizontal meridians at the 3, 4, 5, 6, 7mm optical zones of cornea. The MTF values at spatial frequencies of 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55 and 60 cycles/degree (c/d) were selected., Results: The MTF curve of anterior corneal surface decreased rapidly from low to intermediate frequency (0-15cpd) at various optical zones of cornea, the value decreased to 0 slowly at higher frequency (>15cpd). With the increase of the optical zones of cornea, MTF curve decreased gradually. 3) In the range of 3 mm- 6 mm optical zones of the cornea, the MTF values measured at horizontal meridian were greater than the corresponding values at horizontal meridian of each spatial frequency, the difference was statistically significant (P<0.05). At 7 mm optical zones of cornea, the MTF values measured at horizontal meridian were less than the corresponding values at vertical meridian at 10-60 spatial frequencies(cpd), and the difference was statistically significant in 25, 30, 35, 40, 45, 50 cpd (P<0.05)., Conclusion: MTF can be used to describe the imaging quality of optical systems at anterior corneal surface objectively in detail.