Ethambutol-induced optic neuropathy with rare bilateral asymmetry onset: A case report.

BACKGROUND: Ethambutol-induced optic neuropathy (EON) most commonly manifests as bilateral symmetrical loss of vision and often cause serious and irreversible visual impairment because of the lack of early detection and effective treatment. We followed a case of EON with rare binocular asymmetric clinical manifestations and observed the changes of visual function and retinal structure after drug withdrawal, so as to further understand the clinical characteristics of this disease. CASE SUMMARY: A 54-year-old man complained of gradual visual decline in the left eye. The patient presented with best-corrected visual acuity of 20/20 in the right eye and 20/50 in the left eye. Color vision examination revealed difficulty in reading green color plates in the left eye. The visual field manifested as concentric contraction in the left eye. After nearly a month of drug withdrawal, the right eye had a similar decline in visual function. At the last visit, 19 mo after drug withdrawal, the visual function significantly recovered in both eyes. During follow-up optical coherence tomography (OCT) examination, both eyes manifested the thickness of the retinal nerve fiber layer from mild thickening to thinning and finally temporal atrophy, and the ganglion cell-inner plexiform layer showed significant thinning. The difference was that a reversible structural disorder in the outer retina of the nasal macula was detected in the left eye by macular high-definition OCT. CONCLUSION: Nephropathy and high blood pressure, which damage the retinal microcirculation, may cause damage to the outer layer of the retina. Ethambutol may influence photoreceptor as well as retinal ganglion cells.

Analysis of structural injury patterns in peripapillary retinal nerve fibre layer and retinal ganglion cell layer in ethambutol-induced optic neuropathy.

BACKGROUND: We investigated structural injury patterns in the peripapillary retinal nerve fibre layer (p-RNFL) and ganglion cell inner plexiform layer (GCIPL) caused by ethambutol treatment. METHODS: Sixty-four patients undergoing ethambutol treatment at Zhejiang Chinese Medicine and Western Medicine Integrated Hospital were recruited. Fourteen (14) exhibited visual dysfunction (abnormal group), and the remaining 50 had no visual dysfunction (subclinical group). The thickness of the p-RNFL, total macular retina layer and GCIPL were measured using Cirrus-HD Optical coherence tomography (Cirrus-HD OCT, Cirrus high-definition optical coherence tomography), and compared with 60 healthy, age-matched controls. RESULTS: The p-RNFL thickness was similar in both subclinical and control groups. When compared with the control group, p-RNFL thickness in the abnormal group was significantly increased in the inferior and superior quadrants (GEE, P = 0.040, P = 0.010 respectively). In contrast with the subclinical group, p-RNFL thickness in the inferior quadrant was increased in the abnormal group (GEE, P = 0.047). The GCIPL thickness in the inferonasal and inferior sectors was significantly deceased in the subclinical group when compared with controls (GEE, P = 0.028, P = 0.047, respectively). The average and minimum value of GCIPL thickness, and thickness in the superonasal, inferior, inferotemporal, superotemporal and superior sectors were significantly decreased in the abnormal group when compared with controls (GEE, P = 0.016, P = 0.001, P = 0.028, P = 0.010, P = 0.012, P = 0.015, P = 0.010, respectively). The cube average macular thickness (CAMT) in the abnormal group was significantly thinner than controls (GEE, P = 0.027). CONCLUSIONS: GCIPL measurements using Cirrus-HD OCT detected retinal ganglion cell layer loss following ethambutol treatment, before visual dysfunction occurred.

A novel role for Livin in the response to ultraviolet B radiation and pterygium development.

A pterygium is an inflammatory, invasive and proliferative lesion on the ocular surface, which can decrease visual acuity, damage the ocular surface and affect the appearance of the eye. However, the underlying molecular mechanisms of the pathogenesis remain unclear. In the present study, the role of apoptosis­associated protein Livin in the occurrence and development of pterygium was investigated. Primary samples from quiescent or advanced clinical stages of pterygium and normal human conjunctival tissues were used to assess mRNA and protein expression levels of Livin using reverse transcription­quantitative PCR and immunohistochemistry, respectively. Livin was knocked down in pterygium epithelial cells (PECs) using small interfering RNA (siRNA), to investigate the role of Livin in PEC viability, migration, invasion ability and apoptosis. The cell viability, invasion ability and apoptosis of PECs following ultraviolet B (UVB) radiation alone or in combination with Livin silencing were also analyzed. Expression levels of Livin increased in the pterygium tissues compared with those in the normal conjunctiva at both the mRNA and protein levels. Livin expression levels in advanced pterygium were significantly higher compared with those in quiescent pterygium samples. Knockdown of Livin expression levels significantly reduced cell migration, invasion ability and cell viability, and induced apoptosis of PECs. Inhibition of Livin expression in PECs increased the expression levels of caspase­7, caspase­3 and E­cadherin, whereas expression levels of Snail were downregulated. Cell viability and invasion ability in PECs was enhanced following UVB radiation and Livin expression upregulated. UVB irradiation induced cell invasion ability of PECs and this was attenuated by Livin­silencing. Transfection with Livin siRNA also partially recovered the apoptosis rate of PECs, which was reduced by UVB irradiation. In conclusion, Livin was upregulated in pterygium, and UVB radiation functions in the development of pterygium by inducing Livin expression.

Unilateral inferior oblique anterior transposition for markedly asymmetric dissociated vertical deviation with unilateral inferior oblique over-action.

BACKGROUND: To evaluate the results of unilateral inferior oblique anterior transposition (IOAT) for markedly asymmetric dissociated vertical deviation (DVD) combined with inferior oblique over-action (IOOA). METHODS: Retrospective chart review of the records of all patients with asymmetric DVD combined with unilateral IOOA in the non-dominant eye who received unilateral IOAT on the non-dominant eye. No other muscles were operated on simultaneously. The amount of DVD and IOOA were measured before and after the operation and statistically analysed. RESULTS: Seventeen patients were included. The mean age at surgery was 23.5 ± 8.4 (range 12-38) years old. The mean postoperative follow-up period was 15.7 ± 7.2 (range 6-32) months. The primary position DVD was 19.6 ± 5.4 (range 14-36) PD preoperatively and decreased significantly to 2.9 ± 2.0 (range 0-8) PD postoperatively (P < 0.01). Preoperatively, there were 2, 7, and 8 patients with + 1, + 2, and + 3 IOOA, respectively, and these were reduced from 2.4 ± 0.7 to 0.3 ± 0.4 postoperatively (P < 0.01). None of the patients were complicated obvious hypotropia, anti-elevation syndrome or IOOA in the contralateral eye. CONCLUSIONS: Unilateral IOAT was recommended in patients with asymmetric DVD coexists with unilateral IOOA.

Effects of simvastatin on expression of Bcl-2 and Bax in myocardium of rats with renal ischemia-reperfusion injury / 中国病理生理杂志

AIM:To observe the effect of simvastatin on myocardial tissue after renal ischemia-reperfusion in-jury and its mechanism .METHODS:A rat model of renal ischemia-reperfusion injury was prepared by clamping the bilat-eral renal arteries for 45 min.The rats (n=36) were randomly divided into sham operation group , renal ischemia-reperfu-sion (I/R) group and simvastatin group with 12 rats in each group.The content of serum creatinine (SCr), blood urea ni-trogen ( BUN) and myocardial tissue malondialdehyde ( MDA) , the myocardial activity of lactate dehydrogenase ( LDH) , creatine kinase (CK) and superoxide dismutase (SOD), and the myocardial protein expression of Bcl-2 and Bax were de-tected.RESULTS:Compared with sham operation group , the content of SCr , BUN and myocardial MDA , and the myo-cardial activity of LDH and CK in I/R group were significantly increased (P<0.05), and the activity of SOD was signifi-cantly decreased (P<0.05).Compared with I/R group, the content of SCr, BUN and myocardial MDA, and the myocar-dial activity of LDH and CK in simvastatin group were significantly decreased ( P<0.05 ) , while SOD activity was en-hanced (P<0.05).The protein expression of Bcl-2 and Bax in sham operation group was less than that in I/R group (P<0.05), and the protein level of Bax in simvastatin group was significantly lower than that in I /R group (P<0.05), while the protein level of Bcl-2 was increased (P<0.05).CONCLUSION:Simvastatin has a protective effect on the my-ocardium of the rats with renal ischemia-reperfusion injury , and the protective mechanism may be related to the elimination of free radicals by simvastatin , increase in the protein expression of Bcl-2 and decrease in the protein expression of Bax .