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Intracranial aneurysm (IA) is a devastating cerebrovascular disease characterizing with a potential rupturing risk. In previous studies, the formation of IA was considered to be in a chronic manner, and the ruptured aneurysms might merely derived from the already formed unruptured IA. A 61-year-old male presented to the hospital complaining of a headache. The patient received neuroimage tests, including head computed tomography and digital substraction angiography, to examine the underlying cerebrovascular diseases. Interestingly, we found a newborn ruptured IA with 9-day intervals between 2 whole-cerebral digital subtraction angiography examinations. In summary, the case in our report provides a clue for the natural course that the IA is probably in a "rapid formation, acute rupture" manner.

The incidence and mortality of hepatocellular carcinoma have continued to increase over the last few years, and the medicine-based outlook of patients is poor. Given great ideas from the development of nanotechnology in medicine, especially the advantages in the treatments of liver cancer. Some engineering nanoparticles with active targeting, ligand modification, and passive targeting capacity achieve efficient drug delivery to tumor cells. In addition, the behavior of drug release is also applied to the drug loading nanosystem based on the tumor microenvironment. Considering clinical use of local treatment of liver cancer, in situ drug delivery of nanogels is also fully studied in orthotopic chemotherapy, radiotherapy, and ablation therapy. Furthermore, novel therapies including gene therapy, phototherapy, and immunotherapy are also applied as combined therapy for liver cancer. Engineering nonviral polymers to function as gene delivery vectors with increased efficiency and specificity, and strategies of co-delivery of therapeutic genes and drugs show great therapeutic effect against liver tumors, including drug-resistant tumors. Phototherapy is also applied in surgical procedures, chemotherapy, and immunotherapy. Combination strategies significantly enhance therapeutic effects and decrease side effects. Overall, the application of nanotechnology could bring a revolutionary change to the current treatment of liver cancer.

Glioma is a serious disease burden globally, with high mortality and recurrence rates. CDGSH iron sulfur domain 2 (CISD2) is an evolutionarily conserved protein that is involved in several cancers. However, its role in the prognosis and immune infiltration in glioma remains unclear. In our research, RNA-seq matrix and clinicopathological relevant data for CISD2 were downloaded from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) databases. Human Protein Atlas was used to verify the CISD2 protein level in glioma, and STRING was used to establish relative coexpression gene network. The Kaplan-Meier plotter was adopted to analyze the effect of CISD2 on prognosis. The connection between CISD2 expression and immune infiltration was analyzed using single-sample GSEA (ssGSEA), TIMER, and GEPIA. In contrast to normal tissues, CISD2 expression was significantly higher in glioma tissues, and CISD2 presented a certain diagnostic value in distinguishing glioma tissues from normal tissues. Furthermore, the CISD2 level was correlated with age, histologic grade, histological type, isocitrate dehydrogenase (IDH) status, 1p/19q codeletion status, and primary therapy outcome of glioma, while high CISD2 mRNA expression was correlated with grave overall survival. Multivariate analysis demonstrated that CISD2 was an independent risk factor for patients with glioma. Functional enrichment analysis indicated that CISD2 could regulate proliferation, immune reaction, and mitochondrial function. The results from the ssGSEA and TIMER databases confirmed that CISD2 acts a prominent role in immune cell infiltration in the tumor microenvironment, especially in low-grade glioma (LGG). Furthermore, CISD2 expression was observably correlated to M2 polarization in macrophages with glioma progression. This is the first research to investigate the immune role of CISD2 in glioma. CISD2 may be an innovative prognostic biomarker and can act as a potential target for future therapy for glioma.

BACKGROUND: Intracerebral hemorrhage (ICH) is a cerebrovascular disease with extremely high disability and mortality rates. Glycans play critical roles in biological processes. However, whether glycans can serve as potential biomarkers for determining clinical diagnosis and prognosis in ICH remains determined. METHODS: In this study, we established a lectin-biochip to measure serum glycans levels in ICH patients (n=48) and healthy controls (n=16). An enzyme-linked immunosorbent assay (ELISA) was carried out to determine serum levels of IL-10 and TNF-α in the patients. Correlation analyses of the serum glycan and cytokine levels and the clinicopathological parameters of patients were performed. RESULTS: The biochip-based data revealed that the serum levels of α-Man/α-Glc (ConA), Galβ3GalNAc (PNA), GalNAc (VVA), Fucα6GlcNAc (AAL), α-Fuc (LTL), and Galβ3GalNAc-Ser/Thr (AIL) significantly increased in the super-acute phase of ICH in comparison with healthy controls. Clinicopathological analysis indicated the serum levels of ConA, VVA, and LTL had significant associations with the National Institute of Health Stroke Scale (NIHSS), and serum VVA levels had a significant association with the Mini-Mental State Examination (MMSE) at day 90 after ICH. Correlation coefficient analysis revealed significant correlations between TNF-α and ConA (P

Objective To explore and analyze the influencing factors of facial nerve function retainment after microsurgery resection of acoustic neurinoma. Methods Retrospective analysis of our hospital 105 acoustic neuroma cases from October, 2006 to January 2012, in the group all patients were treated with suboccipital sigmoid sinus approach to acoustic neuroma microsurgery resection. We adopted researching individual patient data, outpatient review and telephone followed up and the House-Brackmann grading system to evaluate and analyze the facial nerve function. Results Among 105 patients in this study group, complete surgical resection rate was 80.9% (85/105), subtotal resection rate was 14.3% (15/105), and partial resection rate 4.8% (5/105). The rate of facial nerve retainment on neuroanatomy was 95.3% (100/105) and the mortality rate was 2.1% (2/105). Facial nerve function when the patient is discharged from the hospital, also known as immediate facial nerve function which was graded in House-Brackmann: excellent facial nerve function (House-Brackmann I-II level) cases accounted for 75.2% (79/105), facial nerve function III-IV level cases accounted for 22.9% (24/105), and V-VI cases accounted for 1.9% (2/105). Patients were followed up for more than one year, with excellent facial nerve function retention rate (H-B I-II level) was 74.4% (58/78). Conclusion Acoustic neuroma patients after surgery, the long-term (≥1 year) facial nerve function excellent retaining rate was closely related with surgical proficiency, post-operative immediate facial nerve function, diameter of tumor and whether to use electrophysiological monitoring techniques; while there was no significant correlation with the patient's age, surgical approach, whether to stripping the internal auditory canal, whether there was cystic degeneration, tumor recurrence, whether to merge with obstructive hydrocephalus and the length of the duration of symptoms.

Metabolic Syndrome (MS) remains the leading cause of mortality and morbidity globally. Adipose tissue releases adipokines that play key roles in metabolic and cardio-cerebro-vascular homeostasis. Subfatin, induced after exercise or upon cold exposure in adipose tissue, is a novel secreted protein homologous to Metrn, a neutrophic factor with angiogenic properties. The protein was proved to be of great significance in the browning of white adipose tissue (BWT) and insulin resistance (IR). It affected insulin sensitivity at least via its local autocrine/paracrine action through AMP-activated protein kinase (AMPK) or peroxisome proliferator-activated receptor δ (PPAR-δ) dependent signaling. Subfatin blocked the release of inflammatory mediators, improved intracellular insulin signal transduction and reversed IR. It also improved glucose tolerance and played a key role in metabolism and cardiovascular and cerebrovascular homeostasis. It was reported that the level of serum subfatin was significantly correlated with the occurrence and severity of coronary heart disease, which might be a new target for the treatment of coronary heart disease. In addition, exercise increased the level of subfatin in circulation and adipose tissue, promoted energy consumption, improved glucose and lipid metabolism, increased the heat production of brown fat, and strengthened the anti-inflammatory mechanism. Given its role in metabolic disorders, subfatin is considered as a candidate biomarker of MS. However, the clinical significance of subfatin remains largely unclear. The purpose of this article is to review the research on the effect of subfatin on MS in recent years.

The embrittlement of nickel-based structural alloys by fission-produced tellurium (Te) is a major challenge for molten salt reactors (MSR). In this study, the effects of thermal exposure time on tellurium diffusion in a candidate MSR structural alloy (Ni–16Mo–7Cr–4Fe) and the consequent mechanical property degradation of the alloy were investigated through surrogate diffusion experiments at 700 °C. The results show that some tellurium reacted with the alloy to form tellurides on the surface, while some tellurium diffused into the alloy along grain boundaries. Ni3Te2 and CrTe were the most stable reaction products at the tested temperature, and the formation of CrTe on the surface induced the Cr depletion at grain boundaries of the alloy. The diffusion depth of Te increased gradually with thermal exposure time, and the diffusion rate kept stable within the test duration of up to 3000 h. The Te diffusion in the alloy caused the embrittlement of grain boundaries, inducing crack formation and strength degradation in tensile test at room temperature.

OBJECTIVE We performed a meta-analysis of reported series of endoscopic third ventriculostomy (ETV) and ventriculoperitoneal shunt (VPS) for non-communicating hydrocephalus to determine whether comparisons between the outcomes in ETV and VPS approaches are valid. METHODS Online databases were searched for articles reporting quantifiable outcome data published between 1990 and 2014 pertaining to the surgical treatment of non-communicating hydrocephalus, with no language restrictions. Eight articles meeting predetermined criteria were included. Data were pooled for 5 surgical outcome measures. RESULTS Our literature search identified 5 prospective cohort studies and 3 retrospective cohort studies with a cumulative number of 652 patients that compared the ETV with VPS for non-communicating hydrocephalus. Analysis of outcomes favored the approach of ETV in terms of duration of surgery (P < 0.00001), incidence of major complications (RR 0.35, 95% CI: 0.24-0.52), and reoperation rate (OR 0.22, 95% CI: 0.12-0.40), whereas it did not favor either approach in terms of length of stay in hospital (P = 0.052) and improvement of symptoms (P = 0.18, OR 0.71, 95% CI: 0.44-1.16). CONCLUSION ETV and VPS have therapeutic equivalence for non-communicating hydrocephalus, whereas ETV can result in lower surgery time, incidence of postoperative complication, and reoperation rate of hydrocephalus.

Patients with neurofibromatosis 1 (NF1) are predisposed to develop central nervous system tumors, due to the loss of neurofibromin, an inactivator of proto-oncogene Ras. However, to our knowledge, only three cases of ependymomas with NF1 have been reported in the literature. The authors present a case of NF1 patient with a spinal cord ependymoma. She was referred for about half a year history of increasing numbness that progressed from her fingers to her entire body above the bellybutton. Magnetic resonance imaging revealed a relative-demarcated, heterogeneously enhanced mass lesion accompanied by perifocal edema in C5-7 level, a left-sided T11 spinous process heterogeneously enhanced mass in soft tissue, intervertebral disk hernia in L2-5 level, and widespread punctum enhancing lesion in her scalp and in T11-L5 level. The patient underwent C5-7 laminectomies and total excision of the tumor under operative microscope, and intraoperative ultrasonography and physiological monitoring were used during the surgery. Histopathologically, her tumor was found to be a ependymoma without malignant features (grade II in the World Health Organization classification). Therefore, no adjuvant therapy was applied. Following the operation, the patient showed an uneventful clinical recovery with no evidence of tumor recurrence after one year of follow-up.

The CO2 reforming of coke oven gas (COG) for hydrogen production was investigated over mesoporous NiO/La2O3-ZrO2 catalysts. At optimized reaction conditions, the conversions of CH4 and CO2 more than 93%, while a H2 selectivity of 94.7% and a CO selectivity of 98.6% have been achieved at 800 °C. The effect of reaction temperature on the catalytic performance was investigated in detail. The catalysts with appropriate La2O3 content showed better catalytic activity and resistance to coking, which will be promising catalysts in the catalytic dry reforming of COG.

The aim of the present study was to investigate the effects of synuclein-γ (SNCG) downregulation by RNA interference (RNAi) on the clonogenicity and invasiveness of MCF-7 breast cancer cells. This study used four pairs of SNCG-specific siRNAs which were designed and cloned into the pGPU6 plasmid for introduction into an MCF-7 cell line. The SNCG knockdown efficacies of the four siRNAs were compared using the reverse transcription polymerase chain reaction (RT-PCR) and immunocytochemistry. The cells’ clonogenic and invasive phenotypes were examined with clonogenic and Boyden chamber assays. In comparison with the non-specific siRNA and empty vector controls, all four SNCG siRNAs were observed to significantly inhibit SNCG expression at the mRNA and protein levels (F=481.06, P

WS2 soft coatings were deposited by medium-frequency magnetron sputtering, multi-arc ion plating and ion beam assisted deposition technique on the YT15 cemented carbide substrates. The influence of the substrate bias voltage on the coating properties has been studied. The coatings exhibited a dense and fine grained structure. WS2 soft coatings with substrate bias voltage of -100 V revealed a better coating properties than other four samples, as the best crystallization of (002) preferred crystal orientation of Ⅱ texture, the most smooth and uniform microstructure of the coating, the largest critical load of 43.25 N and the largest coating thickness of 1.5 μm. But the microhardness of sample S1 was only 515.4 Hv. The critical load and the thickness of WS2 coatings decreased firstly, then increased, and finally reduced with the increasement of substrate bias voltage. And the microhardness of the coatings decreased firstly, then increased, and decreased, finally increased with the increasement of substrate bias voltage.

Pd (0.1-1 wt%) loaded Ni/Mg(Al)O catalysts have been prepared by co-precipitation and impregnation methods, and their catalytic activities were tested in the catalytic reforming of tar components from hot coke oven gas (COG) with lower steam/carbon (S/C) molar ratio. The 0.5%Pd-12%Ni/Mg3(Al)O bimetallic catalyst derived from hydrotalcite showed excellent catalytic activity. The effect of reaction temperature on the catalytic performance was investigated in detail. Toluene could be completely converted into small gas molecules of CH4, CO and CO2 over the catalyst at S/C=0.42 and 600°C under atmospheric pressure.

The catalytic reforming of toluene was performed to investigate the possibility for directly converting tar components from hot coke oven gas (COG) with lower steam/carbon (S/C) molar ratio to light fuel gases. The Ni0.25Me0.25/Mg2.5(Al)O (Me=Fe, Cu, Zn, Mn) bimetallic catalysts derived from hydrotalcite showed excellent catalytic activity. The effects of various reaction conditions on the catalytic performance were investigated in detail. Toluene could be completely converted into small gas molecules of CH4, CO and CO2 over the catalyst at S/C=0.7 and 650-750 oC under atmospheric pressure. Lower reaction temperature and higher H2 content in feed gas both could promote the formation of CH4, while higher S/C molar ratio benefited the CO yield.

The performance of Ni/SiO2 Catalysts modified by La2O3, ZrO2 and CeO2 were tested in a BaCo0.7Fe0.2Nb0.1O3-δ (BCFNO) membrane reactor by catalytic partial oxidation of coke oven gas (COG) under atmospheric pressure. The results show that the oxygen permeation flux increased dramatically with Ni/RxOy/SiO2 (R = La, Zr or Ce) catalysts by adding the element of rare earth especially the La during the reforming reaction. At optimized reaction conditions, the dense oxygen permeable membrane had an oxygen permeation flux around 16.4 ml/cm2•min and a CH4 conversion of 99.2% have been achieved at 900 oC.

The steam reforming of simulated coke oven gas (COG) with toluene as a model tar compound for syngas production was investigated over Ni/Al2O3-MgO catalysts. XRD results showed that the catalysts with high calcination temperature and Al2O3 content after calcination formed (Ni,Mg)Al2O4 spinel and Ni-Mg-O solid solution structure. At optimized reaction conditions, toluene and CH4 can be completely converted, while a H2 yield of 71.8% and a CO yield of 76.1% have been achieved at 800 oC. The catalysts with appropriate calcination temperature and Al2O3 content showed better catalytic activity and resistance to coking, which will be promising catalysts in the catalytic reforming of COG.

The BaCo0.7Fe0.2Nb0.1O3-δ (BCFNO) membranes combined with Ce0.8Re0.2O2-δ (Re=La, Y) layer on the permeation side were used for hydrogen production by partial oxidation reforming of coke oven gas (COG). The Ce0.8Re0.2O2-δ improved the oxygen permeation flux of the membrane by 11–28% at 750 oC. The high oxygen permeation flux achieved using the Ce0.8Re0.2O2-δ surface-coating layer in this work are quite encouraging with a maximum value reaching 19.7 ml/cm2•min at 900 oC, which will be promising surface modification materials in the catalytic partial oxidation reforming of COG.

Exposure to microgravity leads to a sustained elevation in transmural pressure across the cerebral vasculature due to removal of hydrostatic pressure gradients. We hypothesized that ion channel remodeling in cerebral vascular smooth muscle cells (VSMCs) similar to that associated with hypertension may occur and play a role in upward autoregulation of cerebral vessels during microgravity. Sprague-Dawley rats were subjected to 4-wk tail suspension (Sus) to simulate the cardiovascular effect of microgravity. Large-conductance Ca2+-activated K+ (BKCa), voltage-gated K+ (KV), and L-type voltage-dependent Ca2+ (CaL) currents of Sus and control (Con) rat cerebral VSMCs were investigated with a whole cell voltage-clamp technique. Under the same experimental conditions, KV, BKCa, and CaL currents of cerebral VSMCs from adult spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) were also investigated. KV current density decreased in Sus rats vs. Con rats [1.07 ± 0.14 ( n = 22) vs. 1.31 ± 0.28 ( n = 16) pA/pF at +20 mV ( P < 0.05)] and BKCa and CaL current densities increased [BKCa: 1.70 ± 0.37 ( n = 23) vs. 0.88 ± 0.22 ( n = 19) pA/pF at +20 mV ( P < 0.05); CaL: −2.17 ± 0.21 ( n = 35) vs. −1.31 ± 0.10 ( n = 26) pA/pF at +10 mV ( P < 0.05)]. Similar changes were also observed in SHR vs. WKY cerebral VSMCs: KV current density decreased [1.03 ± 0.33 ( n = 9) vs. 1.62 ± 0.64 ( n = 9) pA/pF at +20 mV ( P < 0.05)] and BKCa and CaL current densities increased [BKCa: 2.54 ± 0.47 ( n = 11) vs. 1.12 ± 0.33 ( n = 12) pA/pF at +20 mV ( P < 0.05); CaL: −3.99 ± 0.53 ( n = 12) vs. −2.28 ± 0.20 ( n = 10) pA/pF at +20 mV ( P < 0.05)]. These findings support our hypothesis, and their impact on space cardiovascular research is discussed.

To improve the existing human papillomavirus type16 (HPV16) virus-like particle (VLP) preparation, a highly efficient, economical and timesaving system was established. Sf-9 cells were infected with recombinant baculovirus containing the target gene encoding HPV16L1 protein with 6xHis tag, and harvested 72 h postinfection (p.i.) at 27 degrees. The ProBond(TM) purification system was used for protein purification. The molecular weight of expressed HPV16L1 protein was 58 kD as revealed by SDS-PAGE, and confirmed by Western blot. The purity of denatured and native HPVL1 proteins that were prepared were 91.9% and 71.5%, respectively, which corresponded to a yield of 2.26 mg denatured protein and 1.84 mg native protein per 2x10(7) cells. The proteins were further analyzed by mouse erythrocyte hemagglutination assay and hemagglutination inhibition assay, and there effects on VLP formation were also visualized by transmission electron microscopy. Results showed that the native protein purified was biologically active as natural HPVL1 protein, inducing the murine erythrocyte agglutination and VLP formation. In addition, the purified recombinant HPV16L1 native protein with 6xHis tag could self-assemble into virions in vitro. Hopefully, the present expression and purification system is promising to be convenient, timesaving and economical for preparation of HPV16 VLP vaccine.

Thin films of B-site substituted Bi4Ti3O12 (BTO) by Zr, Bi4Ti3−xZrxO12 (BTZx, x=0.2, 0.5, 1.0 and 1.5), were fabricated on Pt/Ti/SiO2/Si substrates by pulsed laser deposition. Structures and properties of the films were studied as functions of Zr composition. Structure characterization was conducted by X-ray diffraction, scanning electron microscopy, and Raman spectroscopy. The Zr substitution does not change the layered structures of the BTZx. However, with increasing x from 0.2 to 1.5, the vibration modes of the TiO6 octahedra weaken greatly, which is responsible for the corresponding weakening ferroelectricity the remnant polarizations are 14.8, 11.2, 2.4, and 1.4 μC/cm2, respectively. Additionally, the Zr substitution cannot improve the fatigue-resistance of BTZx significantly. After 7.22×109 switching cycles, the nonvolatile polarization decreases by 30.3 and 64.9% of the initial values for x=0.2, and 0.5, respectively. The dielectric properties of these films are also investigated briefly. The relationship between the structures and properties is established experimentally.

Malignant peripheral nerve sheath tumors (MPNSTs) are very rare soft tissue sarcomas, usually arising from somatic soft tissues or peripheral nerves. Primary MPNST of the cerebellopontine angle is extremely rare, with only a single case reported so far. Here, we report an unusual case of MPNST in cerebellopontine angle in a 25-year-old man presented with dizziness, left facial numbness, and tinnitus. After hospitalization, the tumor was treated with complete surgical excision followed by adjuvant chemotherapy and radiotherapy. Histologically, the tumor showed malignant spindle cells, which were with focal S-100 positivity on immunohistochemistry, and a diagnosis of the MPNST was made. This case is being reported for its rarity and presence in cerebellopontine and illustrated the difficulties in the diagnosis and treatment of MPNST, which to the best of our knowledge, has not been described before in the soft tissue sarcomas.

We investigate the correlation between the light emission spectra of Au–Al2O3–Al junctions and the surface morphology of the junction obtained by atomic force microscopy (AFM). From the AFM micrographs, we find a self-correlation length of our junction of about 0.4 μm, which corresponds to surface plasmon polarition (SPP) energies of about 2.0, 1.76, and 1.3 eV at the Au–air, Al–Al2O3, and Au–Al2O3 interfaces, respectively. This agrees well with spectrum peaks observed at 630 nm (2.0 eV) and 700 nm (1.77 eV). A platform region from 800 to 850 nm (1.48 eV) in the spectrum is proposed to result from the overlap of SPP modes at the Au–Al2O3 and Al–Al2O3 interfaces. SPP modes at all three interfaces contribute to light emission via interface roughness in our system.

Applying a combinatorial methodology, (1−x)Na0.5Bi0.5TiO3−xBaTiO3 (NBT-BT) thin-film chips were fabricated on (001)-LaAlO3 substrates by pulsed laser deposition with a few quaternary masks. A series of NBT-BT library with the composition of BT ranged from 0 to 44% was obtained with uniform composition and well crystallinity. The relation between the concentration of NBT-BT and their structural and dielectric properties were investigated by x-ray diffraction (XRD), evanescent microwave probe, atomic force microscopy, and Raman spectroscopy. An obvious morphotropic phase boundary (MPB) was established to be about 9% BT by XRD, Raman frequency shift, and dielectric anomaly, different from the well-known MPB of the materials. The result shows the high efficiency of combinatorial method in searching new relaxor ferroelectrics.

Leiomyosarcoma (LMS) is a malignant tumor of smooth muscle cells for which few effective therapies exist. A subset of LMS cases express macrophage colony-stimulating factor (CSF1) and the resultant tumor-associated macrophage (TAM) infiltration predicts poor clinical outcome. Further, TAMs have been shown to increase tumor angiogenesis. Here, we analyzed 149 LMS cases by immunohistochemistry for vascular marker CD34 and show that high microvessel density (MVD) in nongynecological LMS cases significantly predicts poor patient outcome. The majority of high MVD cases were also CSF1-positive, and when combining high MVD with CSF1 expression, an even stronger prognostic correlation with patient outcome was obtained. Gene expression profiling revealed that MVD has a stronger correlation with CSF1 expression than with expression of vascular endothelial growth factor isoforms, which have traditionally been used as markers of angiogenesis and as anti-angiogenic therapeutic targets. Finally, patterns of CSF1 expression and TAM recruitment remained consistent between primary tumors and their metastases, and between primary tumors and those grown as xenografts in mice, highlighting the stability of these features to the biology of LMS tumors. Together, these findings suggest an important role for CSF1 and the resulting TAM infiltration in the pathological neovascularization of LMS tumors and provide a rationale for CSF1-targeted therapies in LMS.

Introduction: Exposure to high +G z acceleration forces on a centrifuge or in an aircraft can severely decrease cerebral blood perfusion and cause rapid G-induced loss of consciousness. However, milder acceleration may gradually reduce cerebral blood flow and affect cognitive function in subtler ways. This study used lower body negative pressure (LBNP) to mimic +G z circulatory effects in order to study cerebral hemodynamics and brain function. Methods: Subjects were 15 healthy men, 19-21 yr of age. They were exposed to LBNP at two levels for 5 min each separated by a 10-min recovery period. The conditions were low (LO), -4.00 kPa (-30 mmHg) and high (HI), -6.67 kPa (-50 mmHg). Variables measured before, during, and after LBNP included cerebral blood flow velocity (CBFV) in the middle cerebral artery, blood oxygen saturation (S a O 2 ), heart rate (HR), blood pressure, P300 of event-related EEG potentials, reaction time, and tracking error. Results: LO significantly reduced CBFV at 4 and 5 min, increased HR, and decreased the amplitude of P300, but none of the other variables changed from baseline. In contrast, HI produced significant changes in most variables: CBFV decreased at 2 min and then fell further at 4 and 5 min, HR increased, and S a O 2 decreased. Significant neurocognitive changes included increased latency and reduced amplitude of P300, slower reaction time, and greater tracking error. Conclusion: The higher level of LBNP used here reduced cerebral perfusion sufficiently to impair neurocognitive function. This model may be useful for further studies of these and other variables under closelv controlled conditions.

The aim of the present study was to investigate the changes in single-channel currents of large conductance calcium-activated potassium channels (BK(Ca) channels) in cerebral vascular smooth muscle cells (VSMCs) of rats after 1-week simulated microgravity. Sprague-Dawley rats were subjected to tail-suspension (SUS) to simulate cardiovascular deconditioning due to microgravity. Cytosolic calcium ([Ca(2+)](i)) was examined by laser-scanning confocal microscopy with calcium-sensitive-dye Fluo-3/AM as fluorescent probe. Single-channel currents of BK(Ca) channels were measured with cell-attached membrane patches bathed in symmetrical high potassium solution. The [Ca(2+)](i)i level was significantly higher in cerebrovascular myocytes of SUS than that of control (CON) rats. The probability of open (Po) and the mean open time (To) of BK(Ca) channels in cerebral VSMCs significantly increased in SUS as compared with CON. However, there were no significant differences in the unitary conductance and mean close time (Tc) between the two groups. The results obtained suggest that both the elevated [Ca(2+)](i) and enhanced single-channel activities of BK(Ca) channels in cerebral VSMCs might be among the electrophysiological mechanisms that mediate the increased vasoreactivity and hypertrophic change in cerebral arteries during adaptation to simulated microgravity in rats.

The aim of the present study was to examine the changes in the function of voltage-dependent calcium channels (VDC) of vascular smooth muscle cells (VSMCs) isolated from small mesenteric arteries of rats subjected to 1-week or 4-week simulated weightlessness. The whole-cell recording mode was used to record current densities and Ba(2+) was used as charge carrier. Curves and fitting parameters describing steady-state activation and inactivation characteristics of VDC were thus obtained. The inward currents recorded from the VSMCs of small mesenteric arteries were mainly the Ba(2+) currents through the long-lasting type VDC (L-VDC). Compared with that of the control rats, the L-VDC current density of VSMCs from small mesenteric arteries showed a trend toward a decrease in the rats after 1-week , while a significant decrease was observed in the rats after 4-week simulated weightlessness. However, there were no significant differences in the opening and closing rates of L-VDCs, the position of steady-state activation and inactivation curves, and in the parameters, V(0.5) and k, between either of the two groups and its respective control group. The membrane capacitance and the reversal potential of the VSMCs from the small mesenteric arteries of rats after simulated weightlessness also showed no significant changes. These findings suggest that the decreased function of the L-VDC in hindquarter VSMCs might be one of the electrophysiological mechanisms that mediate the depressed vasoreactivity and atrophic change in hindquarter arteries during adaptation to simulated weightlessness in rats.

An approach to 3D non-rigid motion estimation using improved simulated annealing algorithm (SA) from monocular image sequence is proposed. First, the affine motion model of non-rigid object is presented. Then, the energy function, which can reflect the joint probability distribution of motion parameters and the constraints relation of local 3D motion parameters, is established in Markov random field (MRF). After the limitations of classical SA and the features of motion-parameters estimation are analyzed, an improved SA is used to minimize the energy function. Experiment results from two synthetic image sequences demonstrate the robustness of solutions and the feasibility of our algorithm.

The purpose of this study was to test the hypothesis that differential autoregulation of cerebral and hindquarter arteries during simulated microgravity is mediated or modulated by differential activation of K+ channels in vascular smooth muscle cells (VSMCs) of arteries in different anatomic regions. Sprague-Dawley rats were subjected to 1- and 4-wk tail suspension to simulate the cardiovascular deconditioning effect due to short- and medium-term microgravity. K+ channel function of VSMCs was studied by pharmacological methods and patch-clamp techniques. Large-conductance Ca2+-activated K+ (BKCa) and voltage-gated K+ (Kv) currents were determined by subtracting the current recorded after applications of 1 mM tetraethylammonium (TEA) and 1 mM TEA + 3 mM 4-aminopyridine (4-AP), respectively, from that of before. For cerebral vessels, the normalized contractility of basilar arterial rings to TEA, a BKCa blocker, and 4-AP, a Kv blocker, was significantly decreased after 1- and 4-wk simulated microgravity, respectively. VSMCs isolated from the middle cerebral artery branches of suspended rats had a more depolarized membrane potential ( Em) and a smaller K+ current density compared with those of control rats. Furthermore, the reduced total current density was due to smaller BKCa and smaller Kv current density in cerebral VSMCs after 1- and 4-wk tail suspension, respectively. For hindquarter vessels, VSMCs isolated from second- to sixth-order small mesenteric arteries of both 1- and 4-wk suspended rats had a more negative Em and larger K+ current densities for total, BKCa, and Kv currents. These results indicate that differential activation of K+ channels occur in cerebral and hindquarter VSMCs during short- and medium-term simulated microgravity. It is further suggested that different profiles of channel remodeling might occur in VSMCs as one of the important underlying cellular mechanisms to mediate and modulate differential vascular adaptation during microgravity.

It has been reported by Delp et al and Ma J et al that the vasoreactivity of hindquarter vessels from simulated weightless rats decreased. Many factors may contribute to the depressed vasoreactivity. Because the potassium channels play an important role in regulating the resting potential and contribute to the action of some vasoactive substances, we speculated that the changes of potassium channels may be an electro-physiological mechanism involved in the depressed vasoreactivity of hindquarter vessels due to simulated weightlessness.

To examine the change of potassium channel function in hindlimb arterial smooth muscle cells in tail-suspended rats and to elucidate the underlying electro-physiological mechanisms responsible for the depressed vascular responsiveness of hindlimb arteries induced by simulated weightlessness.The contractile responsiveness of femoral arterial rings of 1-wk and 4-wk tail-suspended rats to potassium channel blockers, tetraethylammonium chloride (TEA) and 4-aminopyridine (4-AP), were recorded, and the currents of large conductance calcium-dependent potassium channel (BK(Ca)) and voltage activated potassium channel (Kv) of vascular smooth muscle cells (VSMCs) in saphenous arteries from 1-wk tail-suspended rats were recorded using the whole cell recording mode of patch clamp technique.The femoral arteries from of 1-wk and 4-wk tail-suspended rats showed a decreased contractile response to 60 mM KCl, and the ratio of their contractile responses induced by TEA or 4-AP to their responses induced by 60 mM KCl increased significantly after 1-wk and 4-wk simulated weightlessness. However no difference was found between 1-wk and 4-wk tail-suspended rats. The whole cell current recording showed that BK(Ca) current densities and K(v) current densities of VSMCs in saphenous artery increased significantly after 1-wk simulated weightlessness.The contractile response of hindlimb arteries to KCl decreased after simulated weightlessness. The activities of BK(Ca) and K(v) of smooth muscle cells in hindlimb arteries from tail-suspended rats increased, and these changes might be among the electro-physiological mechanisms involved in the depressed vasoreactivity of hindlimb arteries due to simulated weightlessness.

A series of bismuth layer-structured ferroelectrics thin films Srm-3Bi4TimO3m+3(m=3, 4, 5, and 6) were deposited by pulsed laser deposition (PLD) on (001) LaAlO3 single crystal substrate. XRD and Raman studies have been performed. The more sensitive Raman spectra lead to a different understanding on the layer structure of Sr3Bi4Ti6O21 from XRD. This can be attributed to the lager c-axis constant of Sr3Bi4Ti6O21 due to more layers. More layers lead to increasing disorder in the local scale of the average grain.

The changes in potassium currents of vascular smooth muscle cells (VSMCs) isolated from saphenous arteries and the 2nd-6th order branches of the mesenteric arteries of 4-week tail-suspended rats (SUS) were examined using whole cell patch clamp technique. The resting potential (RP) of the VSMCs from SUS group was more negative compared with that of the control group (CON).The whole cell potassium current densities of VSMCs isolated from the saphenous arteries and small mesenteric arteries in SUS group were significantly larger than those of the CON group.The BK(Ca) and K(V) current densities of VSMCs from saphenous arteries and small mesenteric arteries from SUS group were also significantly larger than those from the CON group.It is speculated that the hyperpolarization of VSMCs and decreased calcium influx through voltage-dependent calcium channels might be one of the electrophysiological mechanisms involved in the depressed vasoreactivity of hindquarter arteries induced by simulated weightlessness.

Objective. To investigate the effect of lower body negative pressure (LBNP) in upright seated position on cerebral blood flow velocity, heart rate (HR), and blood oxygen saturation (SaO2) in human. Method. Fifteen young men were selected as subjects. Blood flow velocity in middle cerebral artery (VMCA), HR and SaO2 were measured at 0.5, 1, 2, 3, 4, and 5 min during LBNP and 1, 3, 5 min after -4.00 kPa and -6.67 kPa LBNP in upright seated position respectively. Result. Under -4.00 kPa LBNP, VMCA slowed down at 4, 5 min during LBNP (P0.05), and HR speeded up at 3, 4, 5 min during LBNP (P0.05). There were no significant changes of SaO2. Under -6.67 kPa LBNP, VMCA became slow at 2, 3 min (P0.05), and at 4 and 5 min (P0.01) during LBNP. At 1 min after release of LBNP, VMCA did not recover, after which it recovered to control level. HR significantly increased (P0.01) and SaO2 decreased at 5 min (P0.05) during LBNP. Conclusion. LBNP can cause blood pooling in lower body so that VMCA and brain blood volume decrease. Then it causes loss of consciousness. The results of this experiment may provide experimental data for diagnosis of flight syncope and orthostatic intolerance.