Electrical stimulation of the remaining retinal neurons to restore useful vision has been recently proposed in patients with retinitis pigmentosa(RP) or age-related macular degeneration(AMD). A ...critical element of a retinal prosthesis is the stimulating electrode array, which is placed in close proximity to the retina. It is via the retinal-electrode interface that a retinal prosthesis electrically stimulates nerve cells to produce the perception of light. In this paper, a flexible flat electrode array was developed and used for this study. The electrode array is made of polymide and Au, which has excellent biocompatibility. Computer simulation is used to calculate the electric field by means of the finite element method. The impedance of the electrode array was measured. The electrode array was inserted into the suprachoroidal space in the posterior portion of the rabbit's eye. For electrical stimulation, a biphasic pulse was used. When the electrical stimulation from the suprachoroidal space was applied, the EEP could be recorded with an epidural electrode.
Meningiomas are the most common primary tumors in central nervous system. While recent studies have revealed genetic clues to lower grade human meningiomas, the molecular determinants driving the ...progression and recurrence of anaplastic meningi- oma, the most malignant subtype with a low prevalence but high morbidity, are still poorly understood. It has been proposed that high recurrence rates of malignant meningiomas are linked to cancer stem cells. Indeed, tumor stem-Uke cells have been iso- lated from various meningioma subtypes, but never been obtained from anaplastic meningioma, in this study, we successfully isolated stem-Uke cells from human anaplastic meningioma. These cells are capable of forming spheres and initiating xenograft tumors that recapitulate anaplastic meningioma phenotypes, and thus could serve as an in vitro model for malignant meningi- omas. KLF4, a transcription factor known for its role in sternness maintenance, was identified as one of the most frequently mutated genes in the benign secretory meningioma. Interestingly, we found that KLF4 is downregulated in anaplastic meningi- oma compared with low-grade meningioma subtypes. By manipulating KLF4 expression in anaplastic meningioma stem-like cells, we demonstrated that KLF4 acts as a tumor suppressor during malignant progression in meningioma, affecting apoptosis, prolif- eration, invasion, and cell cycle. These results suggest a potential therapeutic value of KLF4 for clinical intervention of anaplastic meningioma.
Objective： Intracranial meningiomas, especially those located at anterior and middle skull base, are difficult to be completely resected due to their complicated anatomy structures and adjacent ...vessels. It＇s essential to locate the tumor and its vessels precisely during operation to reduce the risk of neurological deficits. The purpose of this study was to evaluate intraoperative ultrasonography in displaying intracranial meningioma and its surrounding arteries, and evaluate its potential to improve surgical precision and minimize surgical trauma. Methods： Between December 2011 and January 2013, 20 patients with anterior and middle skull base meningioma underwent surgery with the assistance of intraoperative ultrasonography in the Neurosurgery Department of Shanghai Huashan Hospital. There were 7 male and 13 female patients, aged from 31 to 66 years old. Their sonographic features were analyzed and the advantages of intraoperative ultrasonography were discussed. Results： The border of the rneningioma and its adjacent vessels could be exhibited on intraoperative ultrasonography. The sonographic visualization allowed the neurosurgeon to choose an appropriate approach before the operation. In addition, intraoperative ultrasonography could inform neurosurgeons about the location of the tumor, its relation to the surrounding arteries during the operation, thus these essential arteries could be protected carefully. Conclusions： Intraoperative ultrasonography is a useful intraoperative technique. When appropriately applied to assist surgical procedures for intracranial meningioma, it could offer very important intraoperative information （such as the tumor supplying vessels） that helps to improve surgical resection and therefore might reduce the postoperative morbidity.
A method was developed to evaluate frequent milking as a means of controlling intramammary infection. An artificial intramammary environment was used to determine growth responses of Escherichia coli ...(P4) to natural changes in the mammary gland resulting from bacterial invasion. Physical conditions manipulated in this model were growth medium, temperature, and oxygen tension. Mathematical modeling was then incorporated to generate predictions concerning growth dynamics of the organism when milking frequency was changed. To test accuracy of the model, initial predictions were derived from bacterial growth data in which E coli was incubated in tryptose soy broth for 12 hours at 37 C and PO2 equal to 23.3 mm of Hg. These predictions matched closely with experimental data in which 12-, 4-, and 2-hour milking intervals were simulated in the artificial intramammary environment. The mathematical model was then used to characterize growth rate data from in vitro experiments in ultra-high temperature-treated milk and in vivo experimental infection data generated with E coli (P4). Predictions generated from this model suggested that increasing milking frequency to 4 or 6 times daily controls growth of E coli for a prolonged period and that 12 times daily milking may lead to elimination of the bacterium
This chapter presents a new maximum entropy (ME) based hybrid inference engine to improve the accuracy of diagnostic decisions using mixed continuous-discrete variables. By fusing the complementary ...fault information provided by discrete and continuous fault features, false alarms due to misclassification and modeling uncertainty can be significantly reduced. Simulation results using a three-tank benchmark system have clearly illustrated the advantages of diagnostics based on mixed continuous-discrete variables. Moreover, in the presence of significant measurement noise, simulation results show that the proposed ME method achieves better performance than the support vector machine classifier. A generalized structure of model-based FDI schemes consists of two stages of residual generation and residual evaluation. In the first stage, measurements of system variables and parameters are compared with the estimated values provided by a dynamic model to generate a residual vector. Then each residual is compared with a pre-designed threshold in the second stage of residual evaluation, and an FDI decision is made based on the binary residual responses.
Two-dimensional photonic crystals working in near infrared region are fabricated into silicon-on-insulator wafer by 248-nm deep UV lithography. We present an efficient way to measure the photonic ...crystal waveguide's light transmission spectra at given polarization states
A novel halophilic bacterium capable of heterotrophic nitrification-aerobic denitrification was isolated from marine sediments and identified as Vibrio diabolicus SF16. It had ability to remove ...91.82% of NH4(+)-N (119.77 mg/L) and 99.71% of NO3(-)-N (136.43 mg/L). The nitrogen balance showed that 35.83% of initial NH4(+)-N (119.77 mg/L) was changed to intracellular nitrogen, and 53.98% of the initial NH4(+)-N was converted to gaseous denitrification products. The existence of napA gene further proved the aerobic denitrification ability of strain SF16. The optimum culture conditions were salinity 1-5%, sodium acetate as carbon source, C/N 10, and pH 7.5-9.5. When an aerated biological filter system inoculated with strain SF16 was employed to treat saline wastewater, the average removal efficiency of NH4(+)-N and TN reached 97.14% and 73.92%, respectively, indicating great potential of strain SF16 for future full-scale applications.
The aetiology of inflammatory bowel disease (IBD) is a multifactorial interplay between heredity and environment
. Here we report that deficiency in SETDB1, a histone methyltransferase that mediates ...the trimethylation of histone H3 at lysine 9, participates in the pathogenesis of IBD. We found that levels of SETDB1 are decreased in patients with IBD, and that mice with reduced SETDB1 in intestinal stem cells developed spontaneous terminal ileitis and colitis. SETDB1 safeguards genome stability
, and the loss of SETDB1 in intestinal stem cells released repression of endogenous retroviruses (retrovirus-like elements with long repeats that, in humans, comprise approximately 8% of the genome). Excessive viral mimicry generated by motivated endogenous retroviruses triggered Z-DNA-binding protein 1 (ZBP1)-dependent necroptosis, which irreversibly disrupted homeostasis of the epithelial barrier and promoted bowel inflammation. Genome instability, reactive endogenous retroviruses, upregulation of ZBP1 and necroptosis were all seen in patients with IBD. Pharmaceutical inhibition of RIP3 showed a curative effect in SETDB1-deficient mice, which suggests that targeting necroptosis of intestinal stem cells may represent an approach for the treatment of severe IBD.
