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Takuji Kurimoto, Kaori Ueda, Sotaro Mori, Mari Sakamoto, Yuko Yamada-Nakanishi, Wataru Matsumiya, Makoto NakamuraDivision of Ophthalmology, Department of Surgery, Kobe University Graduate School of Medicine, Kobe, JapanBackground: Leber hereditary optic neuropathy (LHON) is a maternally inherited disease caused by three missense mutations of mitochondrial (mt) DNA, ie, m 3460 G>A, m 11778 G>A, or m 14484 T>C in the greater portion of LHON. m 11778 G>A mutation is especially observed in >90% of the cases in Japanese families. Although spontaneous remission of visual function infrequently occurs, effective treatment for LHON remains unestablished. Transcorneal electrical stimulation has been shown to be efficacious in individuals with optic neuropathy. However, due to potential risk of corneal damage, repeated treatments are not permissible. In this exploratory study, we will be conducting skin electrical stimulation (SES) as an intervention for patients with LHON having 11778 missense mutation and investigate effectiveness and safety of SES.Methods: This is a single-arm, prospective, open-label exploratory trial focused on patients with LHON having 11778 missense mutation. Eleven patients will be enrolled and receive six consecutive SES once every 2 weeks up to 10 weeks. The safety of the SES will be monitored with specular microscopy, slit-lamp biomicroscopy, fundus examinations, and the observation of facial skin. The primary outcome measure will be the averaged l ogarithm of minimum angle resolution (logMAR) converted visual acuity 1 week after the last SES. Secondary outcome measures include changes, in logMAR at 4 and 8 weeks after the last SES, such as visual field indices measured using Humphrey visual field and microperimetry-3, the thickness of peripapillary retinal fiber and macular ganglion cell complex, multifocal visual evoked potentials, critical flicker frequency, and color vision.Discussion: The results of this propo

Myosin and actin denaturation (0.1 M NaCl, 20 mM Tris-HCl, pH 7.5) of tilapia myofibrils (Mf) during frozen storage at -10, -20, and -40 A degrees C was studied. Ca2+-ATPase inactivation was rapid at -10 A degrees C but very slow at -20 and -40 A degrees C. Myosin retained its solubility at 0.5 M NaCl even after Ca2+-ATPase inactivation. The amount of subfragment-1 generated from the Mf by chymotryptic digestion decreased with decreasing Ca2+-ATPase inactivation. The amount of rod produced in the frozen Mf remained at a high level, explaining the high salt solubility of myosin. Actin denaturation occurred in the Mf during freezer storage, as revealed by chymotrypic digestion patterns that showed a decreased actin content in the digest, and occurred much faster than Ca2+-ATPase inactivation. Analysis of tilapia meat during freezer storage revealed that Ca2+-ATPase inactivation was very slow in the frozen tissue and was ninefold slower at -10 A degrees C than at -20, and -40 A degrees C. Practically no actin denaturation occurred in the frozen meat. Based on these results, we conclude that native actin in frozen meat protects myosin from denaturation during the frozen storage period but that such protection by actin does not extend to Mf due to rapid actin denaturation. Consequently, the Ca2+-ATPase inactivation rate in Mf represents that of myosin itself-with no protection provided by actin. Therefore, the myosin denaturation rate obtained with Mf should not be used for frozen meat. Mf suspended in 0.1 M NaCl is not a suitable model by which to obtain the myosin denaturation rate in frozen fish meat.

Myosin and actin denaturation (0.1 M NaCl, 20 mM Tris-HCl, pH 7.5) of tilapia myofibrils (Mf) during frozen storage at -10, -20, and -40 A degrees C was studied. Ca2+-ATPase inactivation was rapid at -10 A degrees C but very slow at -20 and -40 A degrees C. Myosin retained its solubility at 0.5 M NaCl even after Ca2+-ATPase inactivation. The amount of subfragment-1 generated from the Mf by chymotryptic digestion decreased with decreasing Ca2+-ATPase inactivation. The amount of rod produced in the frozen Mf remained at a high level, explaining the high salt solubility of myosin. Actin denaturation occurred in the Mf during freezer storage, as revealed by chymotrypic digestion patterns that showed a decreased actin content in the digest, and occurred much faster than Ca2+-ATPase inactivation. Analysis of tilapia meat during freezer storage revealed that Ca2+-ATPase inactivation was very slow in the frozen tissue and was ninefold slower at -10 A degrees C than at -20, and -40 A degrees C. Practically no actin denaturation occurred in the frozen meat. Based on these results, we conclude that native actin in frozen meat protects myosin from denaturation during the frozen storage period but that such protection by actin does not extend to Mf due to rapid actin denaturation. Consequently, the Ca2+-ATPase inactivation rate in Mf represents that of myosin itself-with no protection provided by actin. Therefore, the myosin denaturation rate obtained with Mf should not be used for frozen meat. Mf suspended in 0.1 M NaCl is not a suitable model by which to obtain the myosin denaturation rate in frozen fish meat.

Myosin and actin denaturation (0.1 M NaCl, 20 mM Tris-HCl, pH 7.5) of tilapia myofibrils (Mf) during frozen storage at -10, -20, and -40 A degrees C was studied. Ca2+-ATPase inactivation was rapid at -10 A degrees C but very slow at -20 and -40 A degrees C. Myosin retained its solubility at 0.5 M NaCl even after Ca2+-ATPase inactivation. The amount of subfragment-1 generated from the Mf by chymotryptic digestion decreased with decreasing Ca2+-ATPase inactivation. The amount of rod produced in the frozen Mf remained at a high level, explaining the high salt solubility of myosin. Actin denaturation occurred in the Mf during freezer storage, as revealed by chymotrypic digestion patterns that showed a decreased actin content in the digest, and occurred much faster than Ca2+-ATPase inactivation. Analysis of tilapia meat during freezer storage revealed that Ca2+-ATPase inactivation was very slow in the frozen tissue and was ninefold slower at -10 A degrees C than at -20, and -40 A degrees C. Practically no actin denaturation occurred in the frozen meat. Based on these results, we conclude that native actin in frozen meat protects myosin from denaturation during the frozen storage period but that such protection by actin does not extend to Mf due to rapid actin denaturation. Consequently, the Ca2+-ATPase inactivation rate in Mf represents that of myosin itself-with no protection provided by actin. Therefore, the myosin denaturation rate obtained with Mf should not be used for frozen meat. Mf suspended in 0.1 M NaCl is not a suitable model by which to obtain the myosin denaturation rate in frozen fish meat.