Stereogenic-at-Cobalt(III) Complex Catalyzed Halocyclization of Alkynes: Enantioselective Access to Axially Chiral ortho-Halo-C2-indoles.

Here, we report an anionic stereogenic-at-cobalt(III) complex catalysis strategy for the enantioselective halocyclization of ortho-alkynylanilines using N-halosuccinimide (NXS) as the halogen source. This protocol provides a distinct atroposelective approach to access the axially chiral ortho-halo-C2-indole skeletons in excellent yields with good to high enantioselectivities (up to 99% yield, 99:1 er).

Clinical efficacy of the partial rectus muscle transportation procedure for paralytic strabismus.

AIM: To analyze the clinical efficacy of the partial rectus muscle transportation (PRT) procedure for paralytic strabismus due to single rectus muscle palsy. METHODS: In total, 28 patients (31 eyes) who underwent the PRT procedure for paralytic strabismus due to single rectus muscle palsy were retrospectively examined. The following data were collected pre- and postoperatively: angle of deviation in the primary position, presence of diplopia in the primary position, presence of compensatory head posture, and motility of the affected eye. The follow-up period was 6mo. RESULTS: Based on the preoperative and intraoperative findings, different operations were performed: 2 eyes were treated with PRT, 26 eyes were treated with PRT combined with the recession of the antagonist muscle (Am) of the paralytic rectus muscle, and 3 eyes were treated with PRT along with the recession of the Am and the yoke muscle (Ym). On the first day after the operation, 24 patients were found to be orthophoric in the primary position, without diplopia or abnormal head posture. Moreover, 2 patients with monocular lateral rectus muscle palsy had mild overcorrection to 5 prism diopters (PD) and 8 PD, respectively, whereas 2 patients with binocular lateral rectus muscle palsy had mild undercorrection to 8 PD and 10 PD, respectively. During the 6-month follow-up period, the mean deviation was rectified from 96.79±41.21 PD to 0.64±2.38 PD (t=12.48, P<0.001), whereas the deviations in the 2 patients with mild overcorrection were corrected to orthotropia. The mean preoperative limitation of motility improved from -4.55±0.51 to -2.65±0.61 (t=-15.13, P<0.001) after 6mo postoperatively. CONCLUSION: PRT is an effective treatment for complete paralytic strabismus due to single rectus muscle palsy, and can achieve stable clinical efficacy.

[High myopia and retinal ultrastructure of albino guinea-pigs].

OBJECTIVE: To explore the relationship between melanin synthesis and the congenital high myopia of albino guinea-pigs. METHODS: Twelve albino guinea-pigs and 12 pigmented guinea-pigs of 220~250 grams (aged 5~6 weeks) were chosen at random. The eyes were examined with retinoscopy, A-scan ultrasonography and vernier caliper. The retinal structures were examined with light and electronic microscope. RESULTS: The diopter was -19.17 D in albino guinea-pigs and +0.63 D in pigmented guinea-pigs on average. Compared with the pigmented guinea-pigs, the axial dimensions of the albino guinea-pigs were elongated. There was significant difference between the albino guinea-pigs and the pigmented guinea-pigs. The retinal thickness, pigment granules and membrane disc of the outer segment of the visual cells decreased in the albino guinea-pigs, and the membrane disc space became narrow. The normal retinal thickness, plenty of pigment granules , membrane disc and wide membrane disc space could be observed in the pigmented guinea-pigs. CONCLUSION: Albino guinea-pigs have high myopia, and pigmented guinea pigs have light hyperopia. There are structural differences in the retina between albino guinea-pigs and pigmented guinea-pigs. The abnormity of albino guinea-pigs provides optical foundation for its high myopia.

[Antisense c-fos oligonucleotides-induced myopia in guinea pigs].

OBJECTIVE: To characterize the antisense c-fos oligonucleotides that control the expression of immediate-early gene c-fos in retina in order to better understand the mechanism by which antisense c-fos oligonucleotides induced myopia. In this study the signal transduction in the pathway linking visual experience and the regulation of the eye's growth was investigated. METHODS: Thirty-one 3-week guinea pigs were assigned into 3 groups: antisense and sense c-fos oligonucleotides were intravitreally injected every 3 days to the eyes of the experimental guinea pigs at different concentrations; and saline vehicle to control guinea pigs in the same way. The refraction and axial length of the eyes were measured before and after the treatment, and the immediate-early gene c-fos expression in the retina was quantified by immunohistochemistry and RT-PCR. RESULTS: The moderate myopia was induced in high (1 nmol) and low (0.1 nmol) level of antisense c-fos oligonucleotide intravitreous injection (-5.425 D and -5.575 D, respectively) compared with the control ateral eyes. The refraction and axial length of the treated eyes increased, and the expression of immediate-early gene c-fos decreased significantly in the antisense c-fos oligonucleotides intravitreously injected eyes compared with the sense c-fos oligonucleotide intravitreously and saline vehicle injected eyes (P<0.01). The refraction and axial length were of no statistically significant differences among the sense c-fos oligonucleotides-treated eyes and saline-treated eyes and non-treated eyes (P>0.05). CONCLUSION: The obvious myopia can be induced by antisense c-fos oligonucleotides in guinea pigs; antisense c-fos oligonucleotides inhibit c-fos expression in the retina. Immediate-early gene c-fos may be a potential factor in the prevention of myopia and plays an important role in the signal transduction of the retina.