[Research progress of visual prosthesis].

Vision is one of the most important human sensations about the surrounding world. Visual deprivation not only markedly affects the life of blind people, but also gives a heavy burden to their family and the society. A visual prosthesis is an electronic device that helps the blinds to regain visual perception by directly stimulating the visual pathway using the microelectrodes implanted into the body.

Overcoming foreign-body reaction through nanotopography: Biocompatibility and immunoisolation properties of a nanofibrous membrane.

Implantable immunoisolation membranes need to possess superior biocompatibility to prohibit the fibrotic deposition that would reduce the nutrient supply and impair the viability/function of the encapsulated cells. Here, electrospun membranes based on thermoplastic polyurethane (TPU) were fabricated to contain microfibers (PU-micro) or nanofibers (PU-nano). The two types of membranes were compared in terms of their interaction with macrophage cells and the host tissues.

[Relationship between macular morphology and visual function in diabetic macular edema].

Objective: To investigate the changes and relation between macular morphology and macular visual function in different degrees of diabetic macular edema.

Methods: Seventy-eight eyes of 41 diabetic retinopathy patients were included and graded for diabetic macular edema as follows:31 were graded as no macular edema (NE), 26 as non-clinically significant macular edema (NCSME), and 21 as clinically significant macular edema (CSME). Best corrected visual acuity, macular sensitivity, and macular thickness of all included eyes were examed and quantified.

[MRI kidney segmentation based on thresholding and active contour model].

The proposed hybrid image segmentation method, based on MRI renal images, aims at extracting the cortical and medullary regions of the kidney. It incorporates the thresholding segmentation and the active contour model. To begin with, the binary mask was obtained by preprocessing and thresholding.

Photo-sensitive liposomes: chemistry and application in drug delivery.

Photo-sensitive liposomes have been studied for a few decades and various photo-sensitive triggers have been developed so far. This review offers an overview of the different photo-triggering mechanisms for controlled pulsatile content release from liposomes, which have the potential of finding clinical applications as intelligent drug delivery systems.

[The setting up of reflectance confocal microscope and its in vivo application in skin tissue imaging].

This article, introduces setting up of reflectance confocal microscope which is divided into four parts: optical system, scanning system, detecting system and software controlling system. This reflectance confocal microscope realizes in vivo epidermis tissue imaging in mouse skin as well as disease diagnosis related cell parameters measurement.

[The development and challenge of vision prosthesis].

This paper introduces the current development and challenges of vision prosthesis.

[Implementation of eye movement tracking system based on camshift algorithm].

In this article, the implementation of eye movement tracking system includes three procedures: hardware acquisition, data extraction and overall analysis. The system is based on Camshift algorithm with an eye tracking module added, developed on VC++ 6.0.

[Visible light reflectance spectrum for measurement of cancerous tissue].

A goal the authors always pursue is to realize diagnosis of precancer in vivo, real-time and non-invasive. In the present paper, results of diagnosis of certain cancer were obtained by pathological analysis of several samples, and then the visible light reflectance spectrum property of cancerous tissue was acquired by the comparison with the reflectance spectrum of normal tissue in the same organ. It was found that the main result of change in the reflectance spectrum was caused by the increases in hemoglobin and deoxygenated hemoglobin.

[Study and design of the Q-switched Nd:YAG laser control system based on S3C2410].

This paper presents a design of the control system for the Q-switched Nd:YAG laser, which is based on S3C2410, and the emphasis is laid on its hardware & software's design. The LCD interface with the function of a touch screen is implemented by the Qt/Embedded graphical interface application programs.

Stereoselectivity of satropane, a novel tropane analog, on iris muscarinic receptor activation and intraocular hypotension.

Aim: To study the stereoselectivity of satropane (3-paramethylbenzene sulfonyloxy-6-acetoxy tropane), a novel tropane analog, on iris muscarinic receptor activation and intraocular hypotension.

Methods: The assays for radioligand-receptor binding, the contractile responses of isolated iris muscle, the miosis response, and the intraocular hypotension of the enantiomers of satropane were investigated.

Results: In the binding analysis, S(-)satropane (lesatropane) completely competed against the [3H]quinuclydinyl benzilate-labeled ligand at muscarinic receptors in the iris muscle, whereas R(+)satropane failed to completely compete.

Neuroprotection of muscarinic receptor agonist pilocarpine against glutamate-induced apoptosis in retinal neurons.

Neuroprotection offers potential as an alternative therapy for glaucoma. Pilocarpine, as a typical muscarinic receptor agonist, remains among the major intraocular pressure lowering drugs for the conventional treatment of glaucoma. However, whether pilocarpine also possesses neuroprotection against glutamate cytotoxicity in retinal neurons is still unknown.

Evoked membrane potential change in rat optic nerve fiber: computer simulation.

Objective: The optic nerve is a key component regarding research on visual prosthesis. Previous pharmacological and electrical studies has pinned down the main features of the mechanisms underlying the nerve impulse in the rat optic nerve, and this work proposed a mathematical model to simulate these phenomena.

Methods: The main active nodal channels: fast Na+, persistent Na+, slow K+ and a fast repolarizing K+ (A-current) were added on a double layer representation of the axon.

Atomic force microscope observation on biomembrane before and after peroxidation.

Atomic force microscope (AFM) has been used to visualize the morphological change on the surface of erythrocyte membrane before and after oxidation. A smooth surface of intact erythrocyte cell was observed, while treatment by ferrous ion and ascorbate induced hemolysis of intact erythrocytes, generated many holes with average size of 146.6 +/- 33.

[Beam width measurements of the high-power thin disk Yb:KYW femtosecondlaser with a knife-edge method].

A knife-edge method is used here to measure the beam width of the highly repetitive high-power thin disk Yb:KYW femtosecond laser (MABEL-Mannheim Biomedical Engineering Lab, University of Heidelberg, Germany). Presented in this paper is the detailed measuring process together with the results verified by theoretical calculating and scanning electron microscope measurements respectively. Therefore, it is concluded that the knife-dege method is an effective beam width measurement tool of high-power femtosecond lasers.

Re-characterization of three conjugated linolenic acid isomers by GC-MS and NMR.

Conjugated linolenic acids (CLN) refer to a group of octadecatrienoic acids with three conjugated double bonds. Minor positional and geometrical differences among CLN isomers make their separation and identification difficult. We have used GC-MS and NMR to study three common CLN isomers namely alpha-eleostearic acid, beta-eleostearic acid and punicic acid, finding that some signals of olefinic carbon atoms in NMR spectra were mistakenly assigned in the literature.

[Application of femtosecond laser in corneal refractive surgery].

The function of photo-decomposing of femtosecond laser makes it useful in creating precise "cuts" at arbitrary locations within the corneal of almost any conceivable geometry. The applications of femtosecond laser include intrastromal photorefractive keratectomy, creating the pre-cut channels for intra-corneal ring segment, creating lamellar flaps for laser in situ keratomileusis, performing femtosecond lamellar keratoplasty, which represent an entirely new approach for the correction of refractive errors.

[The relationship of magnification change and visual acuity after implanting phakic anterior chamber intraocular lens for extreme high myopia].

Objective: To investigate the change of retinal image magnification and its relationship to post-operative best corrected visual acuity (BCVA) after implanting phakic anterior chamber intraocular lens for extreme high myopia.

Methods: 30 eyes in 23 patients with -15.13 to -29.

Comparison of histologic, biochemical, and mechanical properties of murine skin treated with the 1064-nm and 1320-nm Nd:YAG lasers.

The goal of this study was to compare the effects of the Q-switched 1064-nm Nd:YAG laser and the 1320-nm Nd:YAG laser non-ablative treatments on mouse skin in vivo. Skin elasticity measurements were carried out with a Reviscometer, and skin samples were taken for histological study, hydroxyproline content assay and estimation of collagen type I and III. By the second month after non-ablative treatments, the 1064-nm laser treatment resulted in an average of 25% greater improvement of skin elasticity, 6% more increase of dermal thickness, and 11% higher synthesis of hydroxyproline than the 1320-nm laser.

[Histological and ultrastructural changes of dog skin following hair removal by laser].

Objective: To evaluate the cutaneous histological and ultrastructural changes of dogs following hair removal by Alexandrite laser.

Methods: Seven healthy dogs with dark hair were treated for hair removal with the Alexandrite laser and skin biopsies were taken after 0.5 h, 2, 3, 5, 10, and 30 days.