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Protein aggregation has been proved to be a pathological basis accounting for neuronal death caused by either transient global ischemia or oxygen glucose deprivation (OGD), and inhibition of protein aggregation is emerging as a potential strategy of preventing brain damage. Trehalose was found to inhibit protein aggregation caused by neurodegenerative diseases via induction of autophagy, whereas its effect is still elusive on ischemia-induced protein aggregation. In this study, we investigated this issue by using rat model of transient global ischemia and SH-SY5Y model of OGD. We found that pretreatment with trehalose inhibited transient global ischemia-induced neuronal death in the hippocampus CA1 neurons and OGD-induced death in SH-SY5Y cells, which was associated with inhibition of the formation of ubiquitin-labeled protein aggregates and preservation of proteasome activity. In vitro study showed that the protection of trehalose against OGD-induced cell death and protein aggregation in SH-SY5Y cells was reversed when proteasome activity was inhibited by MG-132. Further studies revealed that trehalose prevented OGD-induced reduction of proteasome activity via suppression of both oxidative stress and endoplasmic reticulum stress. Particularly, our results showed that trehalose inhibited OGD-induced autophagy. Therefore, we demonstrated that proteasome dysfunction contributed to protein aggregation caused by ischemic insults and trehalose prevented protein aggregation via preservation of proteasome activity, not via induction of autophagy.

Rolling bearing is of great importance in rotating machinery, so the fault diagnosis of rolling bearing is essential to ensure safe operations. The traditional diagnosis approach based on characteristic frequency was shown to be not consistent with experimental data in some cases. Furthermore, two data sets measured under the same circumstance gave different characteristic frequency results, and the harmonic frequency was not linearly proportional to the fundamental frequency. These indicate that existing fault diagnosis is inaccurate and not reliable. This work introduced a new method based on data-driven random fuzzy evidence acquisition and Dempster–Shafer evidence theory, which first compared fault sample data with fuzzy expert system, followed by the determination of random likelihood value and finally obtained diagnosis conclusion based on the data fusion rule. This method was proved to have high accuracy and reliability with a good agreement with experimental data, thus providing a new theoretical approach to fuzzy information processing in complicated numerically controlled equipments.

The molecular mechanism of postoperative cognitive dysfunction is largely unknown. Isoflurane has been shown to promote Alzheimer's disease neuropathogenesis. We set out to determine whether the effect of isoflurane on spatial memory is associated with amyloid-beta (A-beta) levels and tau phosphorylation in aged rats.Eighteen-month-old male Sprague-Dawley rats were randomly assigned as anesthesia group (n = 31, received 1.4% isoflurane for 2 hours and had behavioral testing), training group (n = 20, received no anesthesia but had behavioral testing), and control group (n = 10, received no anesthesia and had no behavioral testing). Spatial memory was measured before and 2 days after the anesthesia by the Morris water maze. We divided the anesthesia group into an isoflurane-induced severe memory impairment group (SIG, n = 6) and a no severe memory impairment group (NSIG, n = 25), according to whether the escape latency was more than 1.96 stand deviation of that from the training group. Levels of A-beta and tau in the hippocampus were determined by enzyme-linked immunosorbent assay and quantitative western blot at the end of behavioral testing.We found that isoflurane increased the escape latency in the SIG as compared to that in the training group and NSIG without affecting swimming speed. However, there were no differences in the levels of A-beta and tau among SIG, NSIG, training, and control groups.Isoflurane may induce spatial memory impairment through non-A-beta or tau neuropathogenesis mechanisms in aged rats.

A systematic investigation on the morphology development of polyvinylidene fluoride hollow fiber membrane made using various N-methyl-2-pyrrolidone (NMP) aqueous solutions as an inner coagulant was carried out. The cross-sectional and inner surface morphology were analyzed with scanning electronic microscopy (SEM). It is found that with increase on NMP concentration, the morphology of the resultant membranes gradually shifted from a double-skin to a single-skin structure. When 40.0 ∼ 55.0 wt.% NMP solution was used, some unexpected macrovoids near the inner region were observed. This special morphology feature was attributed to the reduced solidification rate of the inner surface as a result of increase on NMP concentration, which sharply weakened the inner skin strength. While the existence of centralized stress formed in the phase inversion process, such as shrinkage stress from syneresis, resulted in fractured points in the nascent skin surface that finally made it difficult to maintain a uniform structure. Investigations on effects of the dope flow rate and the bore fluid velocity on the morphology of PVDF fiber membranes experimentally confirmed the suggestion. Three model membranes with double skins, single skin and single skin with macrovoids structures, respectively, were used to test their permeation performance in a CO2 membrane contactor system. The experimental results show the membranes without an inner skin present higher permeability and lower mass transfer resistance than the membrane with a double skin structure. © 2010 Wiley Periodicals, Inc. Journal of Applied Polymer Science, 2010

A novel surface morphology of linear pore pattern on poly(vinylidene fluoride-co-hexafluoro propylene) (PVDF–HFP) flat-sheet porous membrane surfaces prepared by phase inversion technique has been observed. This interesting morphology was repeatedly captured from various casting systems, such as PVDF–HFP/N-methyl pyrrolidone(NMP)/glycol, PVDF–HFP/NMP/diethylene glycol, PVDF–HFP/NMP/glycerol and PVDF–HFP/NMP/glucose, with distilled water as a coagulant. The formation of the linear pore pattern was thought to be associated with the orientation of the macromolecular conglomerations in the casting solution, which occurred during the casting process. Thus, relevant experiments were designed and performed to support the hypothesis. The clearly observed linear pore pattern formed with less than 30 s of exposure time before immersing into water bath became faded in 300 s and completely disappeared in 600 s of exposure time, which was in good accordance with the relaxation degree of orientated macromolecular conglomeration. In contrast, the membrane without experiencing the casting process showed a conventional surface morphology, which also demonstrated the effect of the casting process on the membrane surface morphology. In addition, a clearer image of the linear pore pattern was captured when lower concentration polymer dopes were used. In contrast, this phenomenon was invisible for the membrane formed by a higher concentration dope, which is in agreement with the reduction of orientation degree with increasing polymer concentration. Moreover, the systems containing additives with lower viscosity, such as glycerol, glycol, diethylene glycol and glucose, seem to be easier to form a linear pore pattern than the one containing distilled water, the latter produced a nearly elliptical pore pattern on the membrane surface instead. The investigation on this feature may provide more information for a complete description of the initiation and growth of the porous membrane.

Background: Previous studies have shown that activation of the descending noradrenergic inhibition pathway results in analgesia after surgery. However, the time course of activity of the descending noradrenergic pathway after surgery has not been examined previously. Here, we investigated the spinal release of noradrenaline (NA) in the post-operative period in a freely moving rat model of incisional pain. Methods: Loop microdialysis catheters were implanted subarachnoidally via the atlanto-occipital membrane in Sprague–Dawley rats. Twelve healthy rats without neural deficits were divided into two groups, Group A and Group B, following 5 days of recovery. A plantar incision in the right hind paws of rats in Group A was performed under 1.2% isoflurane. All rats in Group B were only anesthetized by 1.2% isoflurane for the same duration. The microdialysate samples for NA determination were collected before anesthesia, 3 h and 1, 2 and 3 days after incision (or isoflurane anesthesia in Group B) in both groups. The cumulative pain scores were assessed at the above time points. Results: The spinal release of NA increased gradually, peaked at 2 days after the incision and remained at the peak level up to the third day after the incision. The cumulative pain scores peaked 3 h after the incision, and gradually decreased afterwards and returned to the baseline values 3 days after the incision. Conclusions: The descending NA tone might be apparently more active in the post-operative period. The descending noradrenergic inhibitory pathway plays an important role in post-operative neuroplasticity.

In this paper, modification of polyimide hollow fiber membrane was carried out by introduction of tetrabutylammonium naphthalenesulfonate (BAN) into the membrane matrix. Permeation performance of modified hollow fibers was investigated helps to compressed air dehydration ability across the membrane. The experimental results showed that water sorption and water vapor permeability obviously increase with increase on BAN content in modified membranes, and air dehydration performance was improved by increasing BAN in membrane and ratio of sweeping gas. Moreover, operational pressure and feed flux also impose on important effect on compressed air dehydration capability.

In the present work, poly(vinylidene fluoride- co -hexafluropropylene) (PVDF-HFP) asymmetric microporous hollow fiber membranes were successfully fabricated using nonsolvent-induced phase inversion method which has not been reported previously. Analyses of thermodynamic characteristics of the PVDF-HFP/NMP/water system without/with PVP as an additive and the rheological property of the spinning dopes were carried out as a first step. Subsequently, the effects of spinning conditions (wet spinning, air gap, bore fluid composition), dope concentration and PVP addition on the resultant hollow fiber membranes were studied in terms of membrane morphology, structure, pure water flux and molecular weight cut-off (MWCO) as well as their hydrophobicity and mechanical properties. It was found that the wet spinning process produced hollow fibers with irregular inner contour under present experimental conditions. The strong viscoelastic property of PVDF-HFP material was thought to be associated with this phenomenon. A partial release of accumulated back stress in the nascent fibers might have caused the macromolecules to move inward in the transverse direction. Increasing the air gap could eliminate this inner contour deformation, as the outer surface of the nascent fiber was not vitrified prior to entering the water bath, thus allowing the orientated macromolecules to be relaxed. In addition, the nascent fiber is generally expected to experience an elongational stretch over the distance of the air gap, which might help to smooth the inner surface. Membranes made from the PVDF-HFP/NMP dopes were found to have small pure water fluxes no matter what the polymer concentration, the bore fluid composition and the air gap were used in the spinning processes. The pure water flux can be increased by adding PVP into the dope solution, up to 5 wt.% PVP in the dope can promote the formation of macrovoids in the membrane. When the PVP content was increased to 10 wt.%, the macrovoids were suppressed, but the membrane still presented a higher porosity, which was reflected from the significant increase in the pure water flux from 60 to 107 L/(h m 2 atm). In addition, PDVF-HFP hollow fiber membranes were more hydrophobic than those membranes made from pure PVDF, the former also exhibited pronounced ductile behavior when compared with the latter.

Parallel reservoir simulators are now widely used with availability of super computers. Modern massively parallel supercomputers demonstrate great power for simulating large-scale reservoir models. However, improving scalability and efficiency for fully implicit methods on emerging parallel architectures is still challenging. In this paper, we present a robust discretization together with a parallel linear solver algorithm; and we explore the parallel implementation on the world’s fastest supercomputer Tianhe-2. Starting with a general compositional model, we focus on the black oil model and developed Parallel eXtension Framework for parallelizing the serial simulator. A parallel preconditioner based on fast auxiliary space preconditioning (FASP) is applied to solve the Jacobian system arising from the fully implicit discretization. The parallel simulator was validated using large-scale black oil benchmark problems, for which parallel scalabilities were tested. Giant reservoir models with over 100 million grid blocks have been simulated within a few minutes, and test the strong scalability of AMG solver with 1 billion unknown. We also demonstrate the parallelization and acceleration using Intel Xeon Phi coprocessors. In the end, the efficiency of the parallel simulator is illustrated by a giant reservoir using up to 10,000 cores, for which the CPU and communication time are summarized for the linear and nonlinear algorithms.

In order to gain a better understanding of the membrane's role in the whole process of mass-transfer in membrane gas–liquid contacting systems, PVDF microporous hollow fiber membranes have been fabricated using three different dope solutions containing N -methyl-2-pyrrolidone (NMP) and different additives. The resultant hollow fibers with different structures were used to make membrane modules, which were then applied as gas–liquid membrane contactors for CO 2 absorption in water. The membranes were characterized and the effect of membrane structure on the mass-transfer was analysed accordingly. It was found that the additives used imposed a significant effect on the final membrane structure under the same spinning conditions. Compared with distilled water, phosphorous acid and glycerol showed a stronger pore-inducing ability. As a result, the membrane #1 or #2 made by the dope with phosphorous acid or glycerol as an additive had a larger pore size and a higher value of MWCO. The finger-like pores also occupied a larger portion on the membranes #1 and #2 than on the membrane #3, which used distilled water as an additive. Moreover, the membranes #1 and #2 presented a much wider pore size distribution than the membrane #3. The different membrane structures turned out to affect CO 2 absorption performance when used as contactors. Since the ratio of the membrane resistance over the overall mass-transfer resistance was increased in the order of #1 2 absorption performance was in the sequence of #1 > #2 > #3. In addition, it was noticed that all the membranes exhibited considerable membrane resistances from 22% to 36% though the model system used was pure CO 2 absorption in distilled water. The partial wetting was probably caused by the capillary condensation of water vapour in the membrane pores instead of water penetration, as the experiment shows that the CO 2 flux of three PVDF membranes was kept almost unchanged over 15 days of operation. In comparison with a commercial double skin layer PVDF membrane, it was found that the membrane with an inner skin-free structure plus a porous substrate is favourable to be used in the membrane gas–liquid contacting process.

Preparation of poly(vinylidene fluoride-co-hexafluoro propylene) (F2.6) flat-sheet asymmetric porous membrane has been studied for the first time. Factors affecting F2.6 membrane pore structure and permeate performance, such as macromolecule pore formers (polyethylene glycol-400, 1000, 1540, 2000 and 6000), the small molecule former (glycerol), swelling agent (trimethyl phosphate) in casting solution, precipitating bath component and temperature, exposure time and ambient humidity, were investigated in detail. Average pore radius and porosity were used to characterize F2.6 membrane structure, and respectively, determined by ultrafiltration and gravimetric method for the wet membrane. Morphology of the resultant membranes was observed by scanning electronic microscopy (SEM). Final test on permeate performance of F2.6 porous membrane was carried out by a direct contact membrane distillation (DCMD) setup. The experimental F2.6 membrane exhibits a higher distilled flux than PVDF membrane under the same operational situations. The determination of contact angle to distilled water also reveals higher hydrophobic nature than that of PVDF membrane.

Genome-wide association studies have found the single nucleotide polymorphism (SNP) c.C2458T, at the caspase recruitment domain family member 14 (CARD14) gene, to be associated with psoriasis. But little is known about the association of c.C2458T and clinical features of psoriasis vulgaris (PsV) in a Chinese cohort. This study was undertaken to further explore the relationship between c.C2458T and risk of psoriasis in southern Chinese subjects and to evaluate the SNP effect on the clinical features of psoriasis. A case-control study was performed involving 345 PsV patients and 206 controls. The variant of c.C2458T was typed using a SNaPshot assay. Statistical analysis was performed using SPSS version 13.0 software. In analysis of the basic situation of the sample, no difference was observed between cases and controls for age and sex. In the frequency distribution of genotypes and alleles in patients and controls, we found no association between the SNP and the risk of PsV. We performed a stratified analysis according to the age of onset, family history and Psoriasis Area and Severity Index (PASI) subphenotypes. We found that the CC genotype was associated significantly with an increased familial history of PsV. The main finding of our study was that the CC genotype was more common in familial cases than in sporadic cases. However, there were no significant differences found in other subphenotypes of age of onset or PASI between patients positive and those negative for a particular phenotype. In conclusion, the SNP c.C2458T may have significant effects on heritability of PsV in our Chinese population.

A new method of measuring the mean size of solvent clusters in swollen polymer membrane is presented in this paper. This method is based on a combination of inverse gas chromatography (IGC) and equilibrium swelling. The mechanism is that weight fraction activity coefficient of solvent in swollen polymer is influenced by its clusters size. The mean clusters size of solvent in swollen polymer can be calculated as the quotient of the weight fraction activity coefficient of clustering system dividing the weigh fraction activity coefficient of non-clustering system. In this experiment, the weigh fraction activity coefficient of non-clustering system was measured with IGC. Methanol, ethanol and polyimide systems were tested with the new method at three temperatures, 20, 40, and 60 °C. The mean clusters size of methanol in polyimide was five, four, and three at each temperature condition, respectively. Ethanol did not form clusters (the mean clusters size was one). In contrast to the inherent narrow temperature range in DSC, XRD, and FTIR methods, the temperature range in IGC and equilibrium swelling is broad. Compared with DSC, XRD, and FTIR, this new method can detect the clusters of solvent–polymer system at higher temperature.

An asymmetric hydrophobic microporous membrane from the copolymer of tetrafluoroethylene and vinyliden fluoride (F2.4) has been fabricated by phase inversion process. Some characteristics, such as mechanical properties and hydrophobicity, have been examined and compared with polyvinylidenefluoride (PVDF) membrane. Experimental data exhibit F2.4 membrane excellent mechanical properties and hydrophobicity. F2.4 microporous membrane was approximately 6–8 times as high as PVDF membrane in stretching strain and extension ratio at break, and contact angle to distilled water of the fore (88.5°) was larger than the latter (80.0°), too. The results from membrane distillation (MD) process were well agreed with the fundamental laws of membrane distillation.

Flat-sheet microporous membranes from F2.4 for membrane distillation (MD) were prepared by phase inversion process. Dimethylacetamide (DMAC) and LiClO4·3H2O/trimethyl phosphate (TMP) were, respectively, used as solvent and pore-forming additives. The effects of casting solution composition, exposure time prior to coagulation and temperature of precipitation bath on F2.4 membrane structure were investigated. The morphology of resultant porous membrane was observed by scanning electron microcopy. Some natures of F2.4 porous membrane after drying in air, such as mechanical properties and hydrophobicity, were exhibited and compared with poly(vinylidene fluoride) (PVDF) membrane prepared by the same ways. Stress-at-break and strength stress of F2.4 microporous membrane are higher than that of PVDF membrane, and elongation percentage of F2.4 membrane at break is about eight-fold as great as that of PVDF membrane. Contact angle of F2.4 microporous membrane to water (86.6±0.51°) was also larger than that of PVDF membrane (80.0±0.78°). MD experiment was carried out using a direct contact membrane distillation (DCMD) configuration as final test to permeate performance of resultant microporous membrane. The permeate flux of F2.4 experimental membrane was higher than that of PVDF membrane under the same operational conditions.

First, water, methanol, ethanol, acetone, and methyl t-butyl ether were used as molecular probes to measure the free volume distribution of a type of polyimide membrane material (HQDEA–DMMDA). The methods were equilibrium swelling and separation membrane technologies. From the Kirchheim theory of free volume distribution, a Gaussian distribution function was determined. The Gaussian distribution function was confirmed with tensile testing and wide-angle X-ray diffraction of the polyimide films. Second, polyimide/Ag3O4 composite hollow-fiber membranes were prepared by dry/wet phase inversion. The separation performances of the composite membranes were characterized with a methanol/methyl t-butyl ether mixture. The change in the separation performances was explained by the free volume distribution function very well. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 871–879, 2005

In this paper, we propose a preconditioner for solving large-scale linear systems arising from fully implicit petroleum reservoir simulation. First, we take several analytical and physical considerations into account, and choose appropriate auxiliary spaces (problems) to design a preconditioner in the framework of auxiliary space preconditioning method. Secondly, we present an efficient implementation of the proposed preconditioner in modern multicore computer environment. Finally, we test the efficiency and robustness of the proposed methods with a large benchmark problem.

In this paper, we study several unsmoothed aggregation based algebraic multigrid (UA-AMG) methods with regard to different characteristics of CPUs and graphics processing units (GPUs). We propose some UA-AMG methods with lower computational complexity for CPU and CPU-GPU, and study these UA-AMG methods mixing with 4 kinds of red-black colored Gauss-Seidel smoothers for CPU-GPU since the initial mesh is structured. These UA-AMG methods are used as preconditioners for the conjugate gradient (CG) solver to solve a class of two-dimensional single-temperature radiation diffusion equations discretized by preserving symmetry finite volume element scheme. Numerical results demonstrate that, UA-NA-CG-s, which wins the best robustness and efficiency among them, is much more efficient than the default AMG preconditioned CG solvers in HYPRE, AGMG and Cusp for CPU; Under CPU-GPU, UA-W-CG-p is the most robust and efficient one, and rather more efficient than the smoothed aggregation based AMG preconditioned CG solver in Cusp.Copyright © 2013 by ASME

Algebraic multigrid(AMG) method is one of the most efficient iterative methods for solving the linear systems which arising from discretizations of partial differential equations. Parallel AMG has been widely used in large-scale scientific and engineering computation. In this paper, considering a class of linear algebraic equations with sparse and banded coefficient matrices, we improve the OpenMP version of BoomerAMG by modifying its modules of the parallel interpolation and the parallel coarse grid operator. The improved version of BoomerAMG is applied to solve the Laplace equation and a class of two-dimensional three-temperature radiative diffusion equations. Numerical results demonstrate that the new method yields better scalability and efficiency.

The effects of early relief of heavy bilateral carotid stenosis and ischemic postconditioning on hippocampus CA1 neurons are still unclear. In this study, we used a rat model to imitate severe bilateral carotid stenosis in humans. The rats were divided into sham group, carotid stenosis group, stenosis relief group and ischemic postconditioning group. Ischemic postconditioning consisted of three cycles of 30 s ischemia and 30 s reperfusion. The cerebral blood flow was measured with a laser Doppler flowmeter. Neuronal death in the CA1 region was observed by hematoxylin-eosin staining, and the number of live neurons was assessed by cell counting under a light microscope. The levels of oxidative products MDA and 8-iso-PGF2α, inflammatory factors IL-1β and TNF-α, and the activities of anti-oxidative enzymes SOD and CAT were assayed by specific enzyme-linked immunosorbent assay (ELISA) kits, respectively. We found that relief of carotid stenosis and ischemic postconditioning could increase cerebral blood flow. When stenosis was relieved, the percentage of live neurons was 66.6% ± 6.2% on day 3 and 62.3% ± 9.8% on day 27, which was significantly higher than 55.5% ± 4.8% in stenosis group. Ischemic postconditioning markedly improved the live neurons to 92.5% ± 6.7% on day 3 and 88.6% ± 9.1% on day 27. Further study showed that, neuronal death caused by relief of stenosis is associated with increased oxidative stress and enhanced inflammatory response, and the protection of ischemic postconditioning is related to inhibition of oxidative stress and suppression of inflammatory response.

In this paper, we propose two parallel Hilbert Space-filling Curve(HSFC) generation algorithms BMIMp and SDDMp based on block matrix iteration method(BMIM) and state diagrams driver method(SDDM) in the CUDA parallel programming mode. Numerical results show that both of them obtain high parallel speedup. Especially, the speedup of BMIMp and SDDMp can reach 207 and 290 respectively for the 14-order HSFC. Furthermore, BMIMp outperforms SDDMp when considering the total computation time.

In this work, a photocatalyst consisting of porphyrin and graphene was designed to reduce CO2 to hydrocarbons under visible light. This catalyst can (1) effectively reduce CO2 to hydrocarbons, particularly to C2H4; (2) selectively control the photogenerated electrons transfer path due to the physico-chemical properties of porphyrin and graphene; and (3) reduce the complexity of investigating this photocatalytic process because the photocatalyst has fewer defects, thus preventing the introduction of interference factors.

Background and purpose It has not been clearly described for mechanisms of postoperative cognitive dysfunction (POCD), but not yet for narcotic in connection with POCD. Acetylcholine plays important roles in learning and memory especially in elderly people. It is not very clear that cholinergic changes in the hippocampus are in relation to spatial memory impairment. The effects of isoflurane, a commonly used inhalation anaesthetic, as well as acetylcholine on learning and memory in the brain tissue of aged rats were observed in present study. We investigated the inhalation anaesthesia drug's effect on cholinergic system to examine whether the regional and progressive cholinergic changes may lead to POCD. Methods Seventeen-month-old rats were randomly assigned to either an isoflurane anaesthesia group ( n = 17) or propofol anaesthesia group ( n = 17). In isoflurane anaesthesia experiment group, isoflurane (1.4 to 1.7% for 2 hours) was delivered via a ventilator to make freely moving microdialysis model. In propofol group, propofol was administered by continuous infusion via a tail vein catheter to make freely moving microdialysis model. They were all mechanically ventilated. Morris Water Maze test was used to assess the learning and memory abilities of all the two groups’ rats twice a day for 5 days. Microdialysis was performed on the freely moving rats to determine the levels of acetylcholine in the brain tissues immediately after each Water Maze test. Results The isoflurane anaesthesia treatment increased the escape latency contrast to propofol anaesthesia group. The isoflurane anaesthesia's rats were then divided into isoflurane-induced severe learning/memory impairment group ( n = 6, mean escape latency is 1.96 times more than that of in propofol anaesthesia group) and the isoflurane-induced mild learning/memory impairment group ( n = 11, mean escape latency is equal or less than 1.96 times of that in propofol anaesthesia group). The results demonstrated that those rats that were categorized in the isoflurane-induced severe learning/memory impairment group had decreased levels of acetylcholine in the brain tissue as compared to those rats categorized in the mild learning/memory impairment group and in propofol anaesthesia group. Conclusion The results indicated that isoflurane may impair learning and memory in aged rats.

Cognitive dysfunction after propofol anesthesia has been previously found. The underlying mechanisms of this sequel remain unclear. Insoluble proteins as major targets of anesthetics participated in various pathophysiological processes. This study aimed to provide evidence that changes in insoluble proteome in rat hippocampus may be involved in molecular mechanism of cognitive dysfunction following propofol anesthesia. Proteins extracted from rat hippocampus were separated by two-dimensional electrophoresis (2-DE). Their expression patterns were observed at 1, 6, 24 h and 7 days after 3 h of propofol anesthesia. Differentially expressed protein spots among groups were submitted to matrix-assisted laser desorption/ionization time of flight mass spectrometer (MALDI-TOF MS) assay and peptide mass fingerprinting (PMF) identification. Identified proteins were further analyzed through Gene Ontology (GO). Results of 2-DE were selectively assayed using Western blot and RT-PCR. Fifty-nine differentially expressed proteins were detected, among which 43 were identified through MALDI-TOF MS. Most identified proteins were distributed in organelles and membranes. According to biological process category, 27 proteins were involved in metabolic process, 19 in developmental process, 14 in stimulus-response, and 21 in biological regulation. Most changes took place within 24 h, with more down-regulation within 6 h. Twelve proteins did not restore to the basic level until the 7th day after propofol anesthesia. Expressions of insoluble proteome dynamically changed following propofol anesthesia. Down-regulations at early stage might produce depressive effects, which may be involved in molecular mechanism of cognitive dysfunction after propofol anesthesia.

A case of 65 year-old Chinese male patient with severe tracheal stenosis due to a massive substernal goiter, is presented. MRI and CT scan revealed that the massive substernal goiter was 9.3 × 6.1 × 4.7 cm in size, displacing the trachea and adjacent large vessels to the patient’s right contributing to severe intrathoracic trachea compression up to 6 cm in length and the narrowest caliber of the trachea only 3.0 mm in diameter. To the best of our knowledge, optimal airway management for the massive substernal goiter resection was considered to be temporary tracheobronchial stent placement pre-operation.