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To explore the strength characteristics of anisotropic rocks caused by mineral directional arrangement during progressive failure process, biotite quartz schist was taken as an example, and triaxial compression tests were carried out on samples with schistosity angles of 0°, 45° and 90°. The macro and micro failure characteristics and progressive failure strength index of the specimens were analyzed, and the differences with other types of anisotropic rock were discussed. The results show that the failure characteristics of biotite quartz schist are closely related to its schistosity. With the schistosity angle increasing from 0° to 90°, the main macro and micro fracture modes of the specimens change from tensile to shear, and then to co-existence of tensile and shear. The strength characteristic values of biotite quartz schist show significant anisotropy. With the increase of schistosity angle, the strengthening effect caused by confining pressure increase on the strength characteristic values weakens, but the change of the strength value has a trend of acceleration. The anisotropic variation law of the ratio of strength characteristic value is not obvious, which gradually weakens and even disappears under high confining pressure. The fracture modes, variations of strength characteristic values and their ratios of anisotropic rocks with directional arrangement of minerals are different from those of rocks with stratified structure. A thorough understanding of the mechanical properties of rocks with directional arrangement of minerals will be helpful to guide the related engineering practice.

• PPZM exhibited significant scavenging activity of DPPH and OH free radicals in vitro. • PPZM effectively against H 2 O 2 -induced cell damage by decreasing LDH and MDA release, and increasing SOD activity. • The neuroprotective effects of PPZM may be involved in the inhibition of mitochondria-dependent apoptosis. • PPZM can be used as the source of natural antioxidants and neuroprotective agents. The pericarp of Zanthoxylum bungeanum Maxim (PZM) is one of eight fascinating condiments and also used as a traditional herbal medicine to treat a variety of diseases. In this study, ultrasound-assisted extraction (UAE) was applied for the extraction of polysaccharides from PZM (PPZM) and the extraction conditions were optimized by response surface methodology (RSM). The obtained PPZM yield (2.60 ± 0.06%) was closely agreed with the predicted value (2.58%), and the optimal extraction conditions obtained were: liquid to solid ratio of 32 mL/g, extraction time of 42 min, and extraction temperature of 61 °C. PPZM was determined to be composed of mannose (Man), rhamnose (Rha), galacturonic acid (GalA), glucose (Glu), galactose (Gal), arabinose (Ara) with a molar ratio of 4.93: 5.03: 71.01: 16.01: 24.87: 18.79, and the average molecular weight (Mw) of PPZM was 1.72 × 105 Da. Typical polysaccharide characteristics were determined by fourier transform infrared spectroscopy (FT-IR). PPZM exhibited remarkable antioxidant activities in vitro. More importantly, PPZM effectively protected adrenal phaeochromocytoma PC12 cells against H 2 O 2 -induced damage by inhibiting the release of lactate dehydrogenase (LDH) and malondialdehyde (MDA), increasing the level of superoxide dismutase (SOD), and inhibiting abnormal apoptosis. Further experiments indicated that the anti-apoptotic effects of PPZM were closely related to down-regulating the expressions of Bax and Caspase-3, and up-regulating the expression of Bcl-2. Therefore, PPZM can be used as the source of natural antioxidants and neuroprotective agents. [ABSTRACT FROM AUTHOR]

Neural stem cell (NSC) transplantation is a promising strategy for replacing lost neurons following spinal cord injury. However, the survival and differentiation of transplanted NSCs is limited, possibly owing to the neurotoxic inflammatory microenvironment. Because of the important role of glucose metabolism in M1/M2 polarization of microglia/macrophages, we hypothesized that altering the phenotype of microglia/macrophages by regulating the activity of aldose reductase (AR), a key enzyme in the polyol pathway of glucose metabolism, would provide a more beneficial microenvironment for NSC survival and differentiation. Here, we reveal that inhibition of host AR promoted the polarization of microglia/macrophages toward the M2 phenotype in lesioned spinal cord injuries. M2 macrophages promoted the differentiation of NSCs into neurons in vitro. Transplantation of NSCs into injured spinal cords either deficient in AR or treated with the AR inhibitor sorbinil promoted the survival and neuronal differentiation of NSCs at the injured spinal cord site and contributed to locomotor functional recovery. Our findings suggest that inhibition of host AR activity is beneficial in enhancing the survival and neuronal differentiation of transplanted NSCs and shows potential as a treatment of spinal cord injury., Competing Interests: None

Caspase-8 plays an important role in the mediation of inflammation and the effect of its role in subarachnoid hemorrhage remains elusive. The nucleotide-binding oligomerization domain-like receptor protein 3 inflammasome has been postulated to mediate inflammation during SAH. The aim of the present study was to investigate the effects of caspase-8 inhibition on SAH injury and further elucidate the molecular mechanisms. In this study, a subarachnoid hemorrhage model was established by endovascular perforation process in adult male Sprague-Dawley rats. Z-IETD-FMK (0.5, 1, 2 mg/kg; an inhibitor of caspase-8) was delivered via intravenous (tail vein) injection immediately after subarachnoid hemorrhage. After 12 hours of subarachnoid hemorrhage, western blot assay showed that the expression of cleaved caspase-8 was significantly increased at 12 hours, peaked at 24 hours, and then decreased at 72 hours after subarachnoid hemorrhage. Immunofluorescence staining demonstrated that caspase-8 was expressed in microglia after subarachnoid hemorrhage. Z-IETD-FMK significantly improved neurological deficits and reduced brain water content 24 hours after subarachnoid hemorrhage. The Morris water maze and rotarod test confirmed that Z-IETD-FMK significantly improved spatial learning and memory abilities and motor coordination at 21-27 days after subarachnoid hemorrhage. Furthermore, inhibition of caspase-8 activation reduced the expression of pyrin domain-containing 3, caspase-1, and interleukin-1β after subarachnoid hemorrhage. In conclusion, our findings suggest that caspase-8 inhibition alleviates subarachnoid hemorrhage-induced brain injuries by suppressing inflammation. The study was approved by the Institutional Animal Ethics Committee of the First Affiliated Hospital, School of Medicine, Zhejiang University, China (approval No. 2016-193) on February 25, 2016., Competing Interests: None

Objective: To measure the plasma concentrations of three endogenous opioid peptides and the levels of preproenkephalin (PPE) and preprodynorphin (PPD) mRNA in peripheral blood lymphocytes of patients during scheduled surgery performed under intravenous general anaesthesia combined with an epidural block., Methods: Patients were anaesthetized and arterial blood was collected at 0 (baseline), 20, 40, 60, and 80 min during surgery. The plasma concentrations of β-endorphin, leucine-enkephalin and dynorphin A were measured using radioimmunoassay. Reverse transcription-polymerase chain reaction was used to measure the levels of PPD and PPE mRNA in peripheral blood lymphocytes collected during surgery., Results: Fifteen patients participated in this prospective study. The plasma concentrations of β-endorphin were significantly lower at all time-points compared with the baseline value. The plasma concentrations of leucine-enkephalin and dynorphin A were significantly lower at 40, 60, and 80 min compared with baseline. The PPD/β-actin ratio was significantly lower at 80 min compared with baseline, while the PPE/β-actin ratio showed no significant change., Conclusion: The level of mRNA from two pre-endogenous opioid peptide genes either decreased or remained unchanged during surgery under intravenous general anaesthesia with epidural block, suggesting that patients remained pain free during surgery., (© The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.)

Objectives: To investigate (i) the relationship between the ratio of fresh gas flow to min volume (FGF/MV) and the ratio of the fraction of inspired sevoflurane to the delivered concentration of sevoflurane (FI/FD); (ii) to establish the saturation state of sevoflurane anaesthesia and factors affecting the volume of ejected sevoflurane through the nonrespiratory tract route (nVERT) during the saturation state., Methods: Two studies were undertaken in patients with cancer, scheduled to undergo surgery. All patients received tracheal intubation and inhaled sevoflurane. In study 1, anaesthesia parameters were fixed, the initial FD of sevoflurane was 2.2% vol and the FGF/MV was set to 0.2, 0.3, 0.4 and 1.0 in groups A, B, C and D, respectively. In study 2, FGF = MV and the initial FD of sevoflurane was 2.2% vol, but the tidal volume (TV) was set to 6, 8 or 10 ml/kg in groups I, II and III, respectively., Results: Study 1 (n = 60) showed a positive relationship between FI/FD and FGF/MV. In study 2 (n = 60), when TV was fixed, nVERT increased during the saturation state as FD increased; when FD was fixed, nVERT remained stable, despite increased TV., Conclusions: FI/FD is positively associated with FGF/MV; nVERT is affected by FD but not TV.