Kinetic profiles of photocurrents in cells expressing two types of channelrhodopsin genes.

Channelrhodopsin-2 (ChR2), a light-activated cation-selective ion channel, has been widely used as a tool in optogenetic research. ChR2 is specifically sensitive to wavelengths less than 550 nm. One of the methods to expand the sensitivity of a channelrhodopsin to a wider range of wavelengths is to express another channelrhodopsin in the cells by the transduction of an additional gene.

Single-incision Laparoscopic Appendectomy for acute Appendicitis using a 10-mm Laparoscope and the Glove Port Technique.

Objective: To evaluate the single incision laparoscopic appendectomy (SILA) using existing instruments, the 10-mm laparoscope, and glove port technique.

Methods: SILA was performed on 16 patients (8 male cases, 8 female cases) between June 2012 and September 2015. A 20-mm incision was made in the umbilicus and a wound retractor was placed.

Visual Responses of Photoreceptor-Degenerated Rats Expressing Two Different Types of Channelrhodopsin Genes.

Optogenetic technologies are expected to be applicable for clinical use in restoring vision. However, the degree of recovered visual function is highly dependent on the function of the chosen optogenetic gene. To investigate the effect on visual function of dual expression of genes with different wavelength sensitivities, we transduced a modified Volvox-derived channelrhodopsin gene (mVChR1) via an adeno-associated virus vector into transgenic rats harbouring the ChR2 gene in retinal ganglion cells.

Restoration of the majority of the visual spectrum by using modified Volvox channelrhodopsin-1.

We previously showed that blind rats whose vision was restored by gene transfer of Chlamydomonas channelrhodopsin-2 (ChR2) could only detect wavelengths less than 540 nm because of the action spectrum of the transgene product. Volvox-derived channelrhodopsin-1, VChR1, has a broader spectrum than ChR2. However, the VChR1 protein was mainly localized in the cytoplasm and showed weak ion channel properties when the VChR1 gene was transfected into HEK293 cells.

Essential role of thioredoxin 2 in mitigating oxidative stress in retinal epithelial cells.

The retina is constantly subjected to oxidative stress, which is countered by potent antioxidative systems present in retinal pigment epithelial (RPE) cells. Disruption of these systems leads to the development of age-related macular degeneration. Thioredoxin 2 (Trx2) is a potent antioxidant, which acts directly on mitochondria.

Establishment of monocular-limited photoreceptor degeneration models in rabbits.

Background: Numerous rodent models of photoreceptor degeneration have been developed for the study of visual function. However, no viable model has been established in a species that is more closely related to Homo sapiens. Here, we present a rabbit model of monocular photoreceptor degeneration.

Different anti-oxidant effects of thioredoxin 1 and thioredoxin 2 in retinal epithelial cells.

Age-related macular degeneration (AMD) affects the retina and is the most common cause of blindness in elderly persons in developed countries. The retina is constantly subjected to oxidative stress; to avoid the effects of oxidative stress, retinal pigment epithelial (RPE) cells possess potent anti-oxidant systems. Disruption of these systems leads to dysfunction of RPE cells, which then accelerates the development of AMD.

Age-dependent differences in recovered visual responses in Royal College of Surgeons rats transduced with the Channelrhodopsin-2 gene.

The objective of this study is to investigate age-related differences in recovered visual function in Royal College of Surgeons (RCS) rats transduced with the Channelrhodopsin-2 (ChR2) gene. An adeno-associated virus vector that contained ChR2 was injected intravitreously into young or aged RCS rats. After 4 months, visual evoked potentials were recorded.

Differentiation of neuronal cells from NIH/3T3 fibroblasts under defined conditions.

We attempted to test whether the differentiated NIH/3T3 fibroblasts could be differentiated into neuronal cells without any epigenetic modification. First, a neurosphere assay was carried out, and we successfully generated neurosphere-like cells by floating cultures of NIH/3T3 fibroblasts in neural stem cell medium. These spheres have the ability to form sub-spheres after three passages, and express the neural progenitor markers Nestin, Sox2, Pax6, and Musashi-1.

Susceptibility to N-methyl-D-aspartate toxicity in morphological and functional types of cat retinal ganglion cells.

Background: To examine whether different types of retinal ganglion cells (RGCs) in the cat retina have different survival rates when exposed to N-methyl-D-aspartate (NMDA).

Methods: NMDA injury was induced by intravitreal administration of NMDA at final concentrations of 0.2, 0.

A monogenic dominant mutation in Rom1 generated by N-ethyl-N-nitrosourea mutagenesis causes retinal degeneration in mice.

Purpose: To characterize an N-ethyl-N-nitrosourea-induced dominant mouse mutant, M-1156, that exhibits progressive retinal degeneration and to investigate the pathogenesis of the retinal phenotype in the mutant.

Methods: A positional candidate gene approach was used to identify the causative gene in the M-1156 mutant. Funduscopic examination, light microscopy, transmission electron microscopy, and electroretinography were performed to analyze the M-1156 phenotype.

Channelrhodopsins provide a breakthrough insight into strategies for curing blindness.

Photoreceptor cells are the only retinal neurons that can absorb photons. Their degeneration due to some diseases or injuries leads to blindness. Retinal prostheses electrically stimulating surviving retinal cells and evoking a pseudo light sensation have been investigated over the past decade for restoring vision.

Channelrhodopsin-2 gene transduced into retinal ganglion cells restores functional vision in genetically blind rats.

To test the hypothesis that transduction of the channelrhodopsin-2 (ChR2) gene, a microbial-type rhodopsin gene, into retinal ganglion cells of genetically blind rats will restore functional vision, we recorded visually evoked potentials and tested the experimental rats for the presence of optomotor responses. The N-terminal fragment of the ChR2 gene was fused to the fluorescent protein Venus and inserted into an adeno-associated virus to make AAV2-ChR2V. AAV2-ChR2V was injected intravitreally into the eyes of 6-month-old dystrophic RCS (rdy/rdy) rats.

Presence of myocilin sequence variants in Japanese patients with open-angle glaucoma.

Purpose: To examine the myocilin (MYOC) gene for mutations in Japanese patients with primary open-angle glaucoma (POAG) and to determine the phenotypes of the patients with the mutations.

Methods: One-hundred thirty-eight unrelated Japanese patients with POAG were studied. Genomic DNA was extracted from leukocytes of peripheral blood, and the three coding exons including the intron-exon boundaries were amplified by polymerase chain reaction (PCR) and directly sequenced bi-directionally.

BDNF increases the phagocytic activity in cultured iris pigment epithelial cells.

To investigate the effect of brain derived neurotrophic factor (BDNF) on the phagocytic activity in iris pigment epithelial (IPE) cells, purified porcine photoreceptor outer segments (POS) were applied to cultured IPE cells for three hours. To measure phagocytic activities, bound and total POS were differentially stained using a double immunofluorescence staining method. BDNF increased the binding of POS in IPE cells in a dose-dependent manner.

Restoration of visual response in aged dystrophic RCS rats using AAV-mediated channelopsin-2 gene transfer.

Purpose: To investigate whether the channelopsin-2 (Chop2) gene would restore visual responses in 10-month-old dystrophic Royal College of Surgeons (aged RCS; rdy/rdy) rats, the authors transferred the Chop2 gene into the retinal cells of aged RCS rats using the adenoassociated virus (AAV) vector.

Methods: The N-terminal fragment (residues 1-315) of Chop2 was fused to a fluorescent protein, Venus, in frame at the end of the Chop2 coding fragment. The viral vector construct (AAV-Chop2V) for the expression of the Chop2V in the retina was made by subcloning into an adenoassociated virus vector, including the CAG promoter.

Characteristics of mitochondrial calpains.

Calpains are considered to be cytoplasmic enzymes, although several studies have shown that calpain-like protease activities also exist in mitochondria. We partially purified mitochondrial calpain from swine liver mitochondria and characterized. Only one type of mitochondrial calpain was detected by the column chromatographies.

The TUBERO Project: roadmap for the establishment of biomedical engineering at Tohoku University.

This paper summarizes the background and objectives of the establishment of the Tohoku University Biomedical Engineering Research Organization (TUBERO), established in July 2003 as a part of the "Development of Strategic Research Center" program, funded by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan through its Special Coordination Funds for Promoting Science and Technology. This is the largest project among those funded by the budget for strategic research provided by MEXT. In relation to medical microsystems, one of the vital tasks of the biomedical engineering field selected by TUBERO, the efforts of Tohoku University and collaborative actions undertaken between Tohoku University on the one hand and local governments (Miyagi prefecture and Sendai city) and the national government on the other hand, are introduced.

Hypothermia protects cultured human retinal pigment epithelial cells against indocyanine green toxicity.

Purpose: The aim of this study was to determine whether indocyanine green (ICG) is toxic to cultured human retinal pigment epithelial (ARPE-19) cells, and whether hypothermia can protect the ARPE-19 cells against the ICG toxicity.

Methods: Cultured ARPE-19 cells were exposed to 0.25, 0.

Iris pigment epithelial cell transplantation for degenerative retinal diseases.

The transplantation of different types of cells into the eye to treat retinal diseases has advanced in the past 20 years. One of the types of cells used for transplantation is the iris pigment epithelial (IPE) cell, because autologous IPE cells are easily obtained and their properties are similar to those of retinal pigment epithelial (RPE) cells and retinal cells. IPE cells are transplanted as; freshly isolated or cultured cells to replace defective or diseased RPE cells, genetically modified IPE cells for delivering target molecules to the retina or RPE, and retinal progenitor cells.

Pitavastatin prevents NMDA-induced retinal ganglion cell death by suppressing leukocyte recruitment.

Excitotoxicity is a major cause of retinal ganglion cell (RGC) death during ischemic diseases such as vessel occlusion and diabetic retinopathy. However, the underlying mechanisms are not well understood. Statins, inhibitors of the HMG-CoA reductase, have neuroprotective effects in addition to their original role in lowering cholesterol.

Polymorphisms in Complement Factor H and Hemicentin-1 genes in a Japanese population with dry-type age-related macular degeneration.

Purpose: To determine whether polymorphisms in the Complement Factor H (CFH) gene and the Hemicentin-1 gene at the ARMD1 locus are associated with dry age-related macular degeneration (AMD) in Japanese patients.

Design: Clinically relevant laboratory investigation.

Methods: Eighty unrelated Japanese patients with dry AMD and 196 Japanese control patients were studied.