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Objective To discuss microanatomy features of facial-acoustic nerve complex in suboccipito-retrosigmoidal minimally invasive approach based on virtual reality image model. Methods CT and MRI scans were performed to 5 adult cadaver heads, and then, image data was inputted into Vitrea virtual reality system to establish three-dimensional anatomy model of facial-acoustic nerve complex. Suboccipito-retrosigmoidal approach was simulated by selecting osseous landmark points on the calvaria and skull base. Anatomic exposures in surgical trajectory were observed and measured following minimally invasive design. Statistical comparison was launched by paired t test. Results Routes simulating suboccipito-retrosigmoidal approach for exposure of facial-acoustic nerve complex passed under the inferior edge of transverse sinus. Spacial sequence of nerves and vessels in the route was displayed clearly. Vertebral artery and posterior inferior cerebellar artery did not show in the route. Cerebella, lower cranial nerves, anterior inferior cerebellar artery, facial-acoustic nerve complex were exposed successively in route before minimally invasive design. Then, lower cranial nerves pierced the jugular foramen at the site between the jugular bulb and inferior petrosal sinus. Minimally invasive route was higher than that before minimally invasive design and involved cerebella, anterior inferior cerebellar artery and facial-acoustic nerve complex successively. Lower cranial nerves and jugular bulb were not shown in minimally invasive route. Measure and comparative analysis showed that volumes of route (t = 36.331, P = 0.000) and cerebella (t = 16.775, P = 0.000) involved before minimally invasive design were more than that after minimally invasive design with statistically significant difference. Comparison did not show significant differences for the volumes of facial-acoustic nerve complex (t = 1.680, P = 0.127) and anterior inferior cerebellar artery (t = 1.278, P = 0.233) between routes before and after minimally invasive design. Conclusions Minimally invasive routes of suboccipito-retrosigmoidal approach can reduce surgical injury without sacrifice of anatomic exposure for facial-acoustic nerve complex. doi: 10.3969/j.issn.1672-6731.2014.06.008

Key odorants of red wine made from the hybrid grapes of Marselan (Vitis vinifera L.) were isolated by solid-phase extraction (SPE) and explored by gas chromatography-olfactometry (GC-O) analysis. Application of aroma extract dilution analysis (AEDA) revealed 43 odor-active compounds, and 31 odorants among them were detected with flavor dilution (FD) factors ranging from 9 to 2187. Comprehensive two-dimensional gas chromatography and time-of-flight mass spectrometry (GC × GC-TOF-MS) were exploited to quantitate the aroma-active compounds with FD ≥9. The identification indicated β-damascenone as having the highest FD factors, followed by eugenol, 2,3-butanedione, citronellol, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, phenethyl acetate, guaiacol, and 2-methoxy-4-vinylphenol. A total of 21 compounds were found to have odor activity values (OAVs) >1.0. Aroma reconstitution validation experiments showed a good similarity of blackberry, green pepper, honey, raspberry, caramel, smoky, and cinnamon aroma attributes between the original Marselan wine and the reconstructed wine. In addition, omission tests were carried out to further determine the contribution of odorants to the overall aroma.

In this study, the aroma profiles of Cabernet Sauvignon wines from a new grape growing region, Loess Plateau, China, were established by gas chromatography–olfactometry, gas chromatography–mass spectrometry and sensory analysis. The sensory profiles of wines form five different young vineyards in the Loess Plateau region were obtained by descriptive analysis. Blackcurrant (p < 0.01), pear and dried plum (p < 0.05), mushroom, smoked and green pepper (p < 0.1) had significant differences on the five vineyards. A total of 76 odor-active aroma compounds were identified in the wines, and 45 volatile compounds were selected as those having the greatest impact on the aroma components and these were quantitated by five different methods. In addition, the correlation model of the Loess Plateau region’s sensory characteristics and aroma compounds was established by partial least squares regression (PLSR) to determine the influence of various aroma active substances on aroma attributes.

Gene expression is a complex and quantitative trait that is influenced by both genetic and non-genetic regulators including environmental factors. Evaluating the contribution of environment to gene expression regulation and identifying which genes are more likely to be influenced by environmental factors are important for understanding human complex traits. We hypothesize that by living together as couples, there can be commonly co-regulated genes that may reflect the shared living environment (e.g., diet, indoor air pollutants, behavioral lifestyle). The lymphoblastoid cell lines (LCLs) derived from unrelated couples of African ancestry (YRI, Yoruba people from Ibadan, Nigeria) from the International HapMap Project provided a unique model for us to characterize gene expression pattern in couples by comparing gene expression levels between husbands and wives. Strikingly, 778 genes were found to show much smaller variances in couples than random pairs of individuals at a false discovery rate (FDR) of 5%. Since genetic variation between unrelated family members in a general population is expected to be the same assuming a random-mating society, non-genetic factors (e.g., epigenetic systems) are more likely to be the mediators for the observed transcriptional similarity in couples. We thus evaluated the contribution of modified cytosines to those genes showing transcriptional similarity in couples as well as the relationships these CpG sites with other gene regulatory elements, such as transcription factor binding sites (TFBS). Our findings suggested that transcriptional similarity in couples likely reflected shared common environment partially mediated through cytosine modifications.

Objective To evaluate the utilizing value of virtual reality technique for microanatomy of petrous bone by comparing the anatomic characteristics and data measurement between virtual reality and cadaveric head specimens in subtemporal approach. Methods CT scan data of 15 adult cadaveric heads were inputted into the Dextroscope virtual reality system to build three⁃dimensional model of petrous bone. Petrous bone drilling was performed on cadaveric heads and virtual reality models respectively to expose anatomic structures step by step, and the distance and angle was measured based on selected mark points. Bland⁃Altman method was used for the uniformity of checking. Results Visibility effect of simulation of petrous bone drilling in virtual reality system was good. The anatomical structure of facial nerve in petrous bone, greater superficial petrosal nerve, cochlea, semicircular canal, internal carotid artery and glomus jugulare, were displayed clearly. Comparative analysis between cadaveric head and virtual reality by Bland⁃ Altman method showed that bias for distance between geniculate ganglion and start point of common osseus crus of semicircular canal bony, geniculate ganglion and vertex of cochlea, and vertex of cochlea and start point of horizontal segment of internal carotid artery in petrous bone, were 0.020, 0.020, and ⁃ 0.010 respectively, and 95% confidence intervals were ⁃ 0.240-0.270, ⁃ 0.190-0.220, and ⁃ 0.170-0.150, respectively. Good consistency was demonstrated in scatter diagram. For the limitation of visual angle in cadaveric head, the angle between internal acoustic meatus and groove of great superficial petrosal nerve and the distance between start point of common osseus crus of semicircular canal and superior margin of glomus jugulare could not be measured, while data measurement of petrous bone model in virtual reality system was convenient and quick, without limitation of visual angle. The distance between start point of common osseus crus of semicircular canal and superior margin of glomus jugulare was measured as (4.74 ± 0.20) mm, and the angle between internal acoustic meatus and groove of greater superficial petrosal nerve was (51.34 ± 3.29)° . Conclusion Accurate, objective and measurable results can be obtained in the simulation of petrous bone drilling in subtemporal approach utilizing virtual reality system, and could guide surgical practice in dealing with petroclival lesions． DOI：10.3969/j.issn.1672⁃6731.2012.06.019

Objective To evaluate the microsurgical characteristics of different exposure for cavernous sinus through transfrontal approach by Dextroscope virtual reality system quantitatively. Methods Three ⁃ dimensional anatomic models of cavernous sinus were constructed in the Dextroscope virtual reality system according to CT and MRI of five adult cadaver heads. Triangular facets were made by lining landmark points selected on the calvaria and skull base to simulate craniotomy window and regions exposed for cavernous sinus (triangular facet A, B, and C), respectively. Results As comparison showed for areas of different triangular facets of exposed region, facet B was largest with significant difference (P = 0.000, for all). Comparison did not show significant difference among facet A, B, and C for volume of operative space and brain tissue involved (P > 0.05). Volume of anterior clinoid process drilled before cavernous sinus was larger for facet C than facet B and A (P = 0.000, for all). Volume of exposed internal carotid artery and its branches before surgical entry to cavernous sinus was larger for facet B than facet C and A (P = 0.000, for all). Volume of anterior clinoid process drilled after entering cavernous sinus was larger for facet B than facet C (P = 0.000). Volume of cranial nerves and internal carotid artery in the exposed region of cavernous sinus : facet B > facet C > facet A (P = 0.000, for all). There was no significant difference between facet A and facet B as to the volume of pituitary in the exposed region of cavernous sinus (P > 0.05), and pituitary was not exposed through facet C. Conclusion Convenience, vivid manifestation, quantitative measurement, and repeated utilization are prominent advantages of virtual reality technique to simulate transfrontal approach for exposure of cavernous sinus. DOI：10.3969/j.issn.1672-6731.2011.06.002

Objective To clarify the intrinsic risk factors contributing to postoperative infection in patients with recurrent brain tumor. Methods The clinical characteristics of patients with recurrent intracranial neoplasm were collected and analysed retrospectively. The intrinsic risk factors for postoperative intracranial infection were evaluated by χ2 test. The multivariate Logistic regression analysis was employed to select the independent variables associated with postoperative intracranial infection. Results Tumor size, long-term bed, preoperative extracranial infection, diabetes, malnutrition, anemia, hypoproteinemia, organ dysfunction and autoimmune disease had significant effect on postoperative infection, which revealed by the univariate analysis. Multivariate analysis showed that tumor size, preoperative extracranial infection and diabetes contributed to postoperative intracranial infection as independent risk factors. Conclusion Tumor size (diameter > 5 cm), preoperative extracranial infection and diabetes are potential predictors of high risk for postoperative intracranial infection. Efforts should be made to control the factors mentioned above in order to minimize the probability of postoperative infection in patients with recurrent intracranial neoplasm. DOI:10.3969/j.issn.1672-6731.2011.04.016

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

In the originally published version of this Article, images in Fig. 5n were inadvertently replaced with duplicates of images in Fig. 5o during the production process. This has now been corrected in both the PDF and HTML versions of the Article.

The joint is the weakest link in three-core medium-voltage power cable systems and the temperature is an essential indicator to its insulation condition. Therefore, a model to estimate the temperature inside the three-core cable joint was built based on support vector regression (SVR) with two fixed cable surface temperatures as inputs. The samples for model training were obtained from 3-D transient thermal analyses through finite element method (FEM) under different single-step currents. A temperature-rise test of 15 kV three-core cable joint was carried out and the estimated temperature based on SVR agrees well with the measured result with a maximum error of about 4 °C. Besides, the proposed model could accurately estimate the joint temperature even though the thermal conductivity of armor wrap used in thermal analysis for model training differs from its real value. The accuracies and calculation speed of the proposed model were compared with those of FEM, showing a better generality of our model. A temperature-rise test under unbalanced three-phase currents was performed and the temperature estimation errors are within 6 °C, indicating the applicability of the method. The effect of contact resistance was briefly discussed in the end. This approach helps improve cable operation and maintenance.

Accurate data about the spatial distribution and planting area of maize is important for policy making, economic development, environmental protection and food security under climate change. This paper proposes a new identification method for spring maize based on spectral and phenological features derived from the moderate resolution imaging spectroradiometer (MODIS) land surface reflectance time-series data. The method focused on the spectral differences of different land cover types in the specific phenological phases of spring maize by testing the selections and combinations of classification metrics, feature extraction methods and classifiers. Taking Liaoning province, a representative planting region of spring maize in Northeast China, as the study area, the results indicated that the combined multiple metrics, including the red reflectance, near-infrared reflectance and normalized difference vegetation index (NDVI), were conducive to the maize identification and were better than any single metric. With regard to the feature extraction and selection, maize identification based on different phenological features selected with prior knowledge was more efficient than that based on statistical features derived from the principal component analysis. Compared with the maximum likelihood classification method, the decision tree classification based on expert knowledge was more suitable for phenological features selected from some prior knowledge. In summary, discriminant rules were defined with those phenological features from multiple metrics, and the decision tree classification was used to identify maize in the study area. The producer’s accuracy of maize identification was 98.57%, and the user’s accuracy was 81.18%. This method can be potentially applied to an operational identification of maize at large scales based on remote sensing time-series data.

The numerical study of continuum-rarefied gas flows is of considerable interest because it can provide fundamental knowledge regarding flow physics. Recently, the nonlinear coupled constitutive method (NCCM) has been derived from the Boltzmann equation and implemented to investigate continuum-rarefied gas flows. In this study, we first report the important and detailed issues in the use of the H theorem and positive entropy generation in the NCCM. Importantly, the unified nonlinear dissipation model and its relationships to the Rayleigh–Onsager function were demonstrated in the treatment of the collision term of the Boltzmann equation. In addition, we compare the Grad moment method, the Burnett equation, and the NCCM. Next, differences between the NCCM equations and the Navier–Stokes equations are explained in detail. For validation, numerical studies of rarefied and continuum gas flows were conducted. These studies include rarefied and/or continuum gas flows around a two-dimensional (2D) cavity, a 2D airfoil, a 2D cylinder, and a three-dimensional space shuttle. It was observed that the present results of the NCCM are in good agreement with those of the Direct Simulation Monte Carlo (DSMC) method in rarefied cases and are in good agreement with those of the Navier–Stokes equations in continuum cases. Finally, this study can be regarded as a theoretical basis of the NCCM for the development of a unified framework for solving continuum-rarefied gas flows.

The neural fate commitment of pluripotent stem cells requires the repression of extrinsic inhibitory signals and the activation of intrinsic positive transcription factors. However, how these two events are integrated to ensure appropriate neural conversion remains unclear. In this study, we showed that Pou3f1 is essential for the neural differentiation of mouse embryonic stem cells (ESCs), specifically during the transition from epiblast stem cells (EpiSCs) to neural progenitor cells (NPCs). Chimeric analysis showed that Pou3f1 knockdown leads to a markedly decreased incorporation of ESCs in the neuroectoderm. By contrast, Pou3f1-overexpressing ESC derivatives preferentially contribute to the neuroectoderm. Genome-wide ChIP-seq and RNA-seq analyses indicated that Pou3f1 is an upstream activator of neural lineage genes, and also is a repressor of BMP and Wnt signaling. Our results established that Pou3f1 promotes the neural fate commitment of pluripotent stem cells through a dual role, activating internal neural induction programs and antagonizing extrinsic neural inhibitory signals.

Loops in proteins are flexible regions connecting regular secondary structures. They are often involved in protein functions through interacting with other molecules. The irregularity and flexibility of loops make their structures difficult to determine experimentally and challenging to model computationally. Conformation sampling and energy evaluation are the two key components in loop modeling. We have developed a new method for loop conformation sampling and prediction based on a chain growth sequential Monte Carlo sampling strategy, called Distance-guided Sequential chain-Growth Monte Carlo (DISGRO). With an energy function designed specifically for loops, our method can efficiently generate high quality loop conformations with low energy that are enriched with near-native loop structures. The average minimum global backbone RMSD for 1,000 conformations of 12-residue loops is 1:53 A° , with a lowest energy RMSD of 2:99 A° , and an average ensembleRMSD of 5:23 A° . A novel geometric criterion is applied to speed up calculations. The computational cost of generating 1,000 conformations for each of the x loops in a benchmark dataset is only about 10 cpu minutes for 12-residue loops, compared to ca 180 cpu minutes using the FALCm method. Test results on benchmark datasets show that DISGRO performs comparably or better than previous successful methods, while requiring far less computing time. DISGRO is especially effective in modeling longer loops (10-17 residues).

ObjectiveTo retrospectively compare the efficacy of the titanium mesh cage (TMC) and the nano-hydroxyapatite/polyamide66 cage (n-HA/PA66 cage) for 1- or 2-level anterior cervical corpectomy and fusion (ACCF) to treat multilevel cervical spondylotic myelopathy (MCSM).MethodsA total of 117 consecutive patients with MCSM who underwent 1- or 2-level ACCF using a TMC or an n-HA/PA66 cage were studied retrospectively at a mean follow-up of 45.28 ± 12.83 months. The patients were divided into four groups according to the level of corpectomy (1- or 2-level corpectomy) and cage type used (TMC or n-HA/PA66 cage). Clinical and radiological parameters were used to evaluate outcomes.ResultsAt the one-year follow-up, the fusion rate in the n-HA/PA66 group was higher, albeit non-significantly, than that in the TMC group for both 1- and 2-level ACCF, but the fusion rates of the procedures were almost equal at the final follow-up. The incidence of cage subsidence at the final follow-up was significantly higher in the TMC group than in the n-HA/PA66 group for the 1-level ACCF (24% vs. 4%, p = 0.01), and the difference was greater for the 2-level ACCF between the TMC group and the n-HA/PA66 group (38% vs. 5%, p = 0.01). Meanwhile, a much greater loss of fused height was observed in the TMC group compared with the n-HA/PA66 group for both the 1- and 2-level ACCF. All four groups demonstrated increases in C2-C7 Cobb angle and JOA scores and decreases in VAS at the final follow-up compared with preoperative values.ConclusionThe lower incidence of cage subsidence, better maintenance of the height of the fused segment and similar excellent bony fusion indicate that the n-HA/PA66 cage may be a superior alternative to the TMC for cervical reconstruction after cervical corpectomy, in particular for 2-level ACCF.

In this study, our objective is to evaluate the potential of a novel Sorafenib derivative, named HLC-080, as a new anticancer agent for colon cancer. We firstly carried out MTT assay, colony formation assay, flow cytometry analysis and transwell invasion assay to determine effect of our compound HLC-080 on cell viability, anti-proliferation activity, cell cycle arrest and the intervention on cell invasion, respectively. On the other hand, in vivo antitumor activity of HLC-080 was also tested using H22 xenograft model and the angiogenesis effect of HLC-080 was measured by EA.hy926 tube formation assay. The expression levels of various proteins in HLC-080 treated with HT-29 cell lines were examined using Western blot and ELISA experiments. The results showed that HLC-080 could dramatically inhibit the growth and colony formation of various tumor cells, therefore exhibited remarkable antitumor activity. HLC-080 can induce cell cycle arrest at G1 phase in HT-29 cells and subsequently inhibit the invasive potential of colon cancer cells. HLC-080 also exhibits anti-angiogenesis effect in EA.hy926 model. Additionally, the in vivo study showed that HLC-080 was able to reduced the tumor weight with the rate of 35.81%. And at the concentration of 0.352±0.034 µM, HLC-080 is able to reduce half of the regular protein level of p-c-Raf (Ser259), consequently block Raf/MEK/ERK signaling in HT-29 cell lines. In conclusion, our study suggests that Sorafenib derivative HLC-080 has the potential to inhibit cell proliferation and angiogenesis, Since, HLC-080 is particularly active against human colon cancer cells, our study highlights that HLC-080 and its related analogues may serve as a new anti-cancer drug, particularly against colon cancer.

Papillorenal syndrome (PRS, also known as renal-coloboma syndrome) is an autosomal dominant disease characterized by potentially-blinding congenital optic nerve excavation and congenital kidney abnormalities. Many patients with PRS have mutations in the paired box transcription factor gene, PAX2. Although most mutations in PAX2 are predicted to result in complete loss of one allele's function, three missense mutations have been reported, raising the possibility that more subtle alterations in PAX2 function may be disease-causing. To date, the molecular behaviors of these mutations have not been explored. We describe a novel mouse model of PRS due to a missense mutation in a highly-conserved threonine residue in the paired domain of Pax2 (p.T74A) that recapitulates the ocular and kidney findings of patients. This mutation is in the Pax2 paired domain at the same location as two human missense mutations. We show that all three missense mutations disrupt potentially critical hydrogen bonds in atomic models and result in reduced Pax2 transactivation, but do not affect nuclear localization, steady state mRNA levels, or the ability of Pax2 to bind its DNA consensus sequence. Moreover, these mutations show reduced steady-state levels of Pax2 protein in vitro and (for p.T74A) in vivo, likely by reducing protein stability. These results suggest that hypomorphic alleles of PAX2/Pax2 can lead to significant disease in humans and mice.