Van Herick法及河南眼科研究所改进法检查前房深度估测房角关闭的准确性研究

目的:研究Van Herick法及河南眼科研究所改进法检查前房深度估测房角关闭的准确性。方法:随机选取2018-06/2019-01于我院门诊就诊的40岁及以上患者52例100眼分别行Van Herick法和河南眼科研究所改进法检查前房深度,筛选出周边前房深度≤1/3 CT且>1/4 CT与周边前房深度≤1/4 CT人群,对Van Herick法与河南研究所改进法前房检查法结果进行一致性检验,再行房角镜检查与暗室下UBM检查分别检查周边房角是否关闭。结果:在Van Herick法估测周边前房深度≤1/3 CT且>1/4 CT的患眼中,行房角镜检查与UBM检查结果房角关闭的阳性率分别为39%与43%,在河南眼科研究所改进法估测周边前房深度≤1/3 CT且>1/4 CT的患眼中,行房角镜检查与UBM检查结果房角关闭的阳性率分别为46%与42%;在Van Herick法估测周边前房深度≤1/4 CT的患眼中,行房角镜检查与UBM检查结果房角关闭的阳性率分别为67%与89%;在河南眼科研究所改进法估测周边前房深度≤1/4 CT的患眼中,行房角镜检查与UBM检查结果房角关闭的阳性率分别为70%与100%;对Van Herick法与河南眼科研究所改进法进行一致性检验,在估测周边前房深度≤1/3CT且>1/4 CT时,Kappa值为0.85,一致性较好,在估测周边前房深度≤1/4 CT时,Kappa值为0.83,一致性较好;对房角镜检查结果及UBM检查结果进行一致性检验,在Van Herick法估测周边前房深度≤1/3 CT且>1/4 CT时,Kappa值为0.73,一致性一般,在Van Herick法估测周边前房深度≤1/4 CT时,Kappa值为0.40,一致性一般。对房角镜检查结果及UBM检查结果进行一致性检验,在河南眼科研究所改进法估测周边前房深度≤1/3 CT且>1/4 CT时,Kappa值为0.75,一致性较好,在河南眼科研究所改进法估测周边前房深度≤1/4 CT时,Kappa值为0,一致性较差。结论:Van Herick法及河南眼科研究所改进法前房深度检查在测量人群中房角关闭的具有一定的假阴性率,但准确性较高,仍适合作为估测房角关闭的初步检查方式。     

Hypermorphic expression of centromeric retroelement-encoded small RNAs impairs CENP-A loading

The proper functioning of centromeres requires a complex cascade of epigenetic events involving chromatin and kinetochore assembly; however, the precise mechanism by which this cascade proceeds is unknown. The pivotal event during kinetochore formation is the “loading,” or deposition, of CENP-A. This histone H3 variant is specific to centromeres and replaces conventional H3 in centromeric chromatin. Failure to load CENP-A into mammalian centromeres in late telophase/early G1 of the cell cycle leads to malsegregation and cell division defects in subsequent cell cycles. Mounting evidence supports the hypothesis that an RNA component is involved, although how RNAs participate in centromere formation in mammals has remained unknown. Using the marsupial model, the tammar wallaby, we show that centromeric retroelements produce small RNAs and that hypermorphic expression of these centromeric small RNAs results in disruption of CENP-A localization. We propose that tight regulation of the processing of this new class of small RNAs, crasiRNAs, is an integral component of the epigenetic framework necessary for centromere establishment.     

Increased BrdU incorporation reflecting DNA repair, neuronal de-differentiation or possible neurogenesis in the adult cochlear nucleus following bilateral cochlear lesions in the rat

Neurogenesis is known to occur in response to injury in the brain, for example, as a result of neurodegenerative diseases. However, there have been few investigations into how the brain responds to damage to peripheral sensory nerves, in other areas such as the brainstem. Here, we report that bilateral surgical lesions of the cochlea result in increased incorporation of the DNA replication marker, bromodeoxyuridine (BrdU), in cells of the brainstem cochlear nucleus (CN) of the adult rat, suggesting either cell proliferation or DNA repair. Some of the BrdU-labelled cells colabelled for the mature neuron marker, NeuN and the GABAergic enzyme GAD-65, suggesting the possibility that neurogenesis might have occurred and resulted in the generation of new neurons with a GABAergic phenotype. However, some of the mature neurons also re-expressed immature neuronal intermediate filament and microtuble-associated proteins, without apoptotic neuronal death, which suggests that the colabelling of BrdU with NeuN and GAD-65 may not be a true reflection of neurogenesis, but injury-stimulated neuronal dedifferentiation. These results suggest the possibility that DNA repair, neuronal de-differentiation or possible neurogenesis occurs in the cochlear nucleus, in response to damage to the peripheral auditory system.     

Combined 17α-hydroxylase/17,20-lyase deficiency with short stature: case study

Backgrounds: 17α-hydroxylase/17,20-lyase deficiency (17-OHD) is an uncommon form of congenital adrenal hyperplasia. Most patients are tall owing to delayed closure of epiphyses as a result of deficiency of sex hormones.

Methods: We present a 17-OHD case with unusual short stature and reviewed related literature.

Results: A 17-year-old female patient presented with primary amenorrhea, hypertension, hypokalemia and hypergonadotropic hypogonadism (HH). Sequencing of the CYP17A1 gene identified a homozygous c.985_987delTACinsAA in exon 6 that confirmed the diagnosis of 17-OHD. However, her height (148?cm, height standard deviation score [HSDS] ?2.28) was unusually low compared with that of other 17-OHD patients. Levels of growth hormone (GH) and insulin-like growth factor (IGF)-1 were normal, and the GH provocation test excluded the possibility of GH deficiency. She underwent glucocorticoid and sex-hormone replacement therapy, reaching a final height of 152?cm (HSDS ?1.59). These data suggest that tall stature is not a requisite characteristic of 17-OHD. Further studies are needed to clarify the effects of sex hormone on linear bone growth (LBG) in 17-OHD patients.     

Chronic hypotony management using endoscopy-assisted vitrectomy after severe ocular trauma or vitrectomy

AIM: To report outcomes of endoscopy-assisted vitrectomy (EAV) in patients with chronic hypotony following severe ocular trauma or vitrectomy. METHODS: This was a retrospective, noncomparative case series. Ciliary bodies were evaluated using ultrasound biomicroscopy pre-operatively and direct visualisation intraoperatively. All selected individuals (seven patients/seven eyes) underwent EAV. Removal of ciliary membrane and traction, gas/silicone oil tamponade (GT/SOT), and scleral buckling (SB) were performed in selected eyes. Outcome measurements mainly included intraocular pressure (IOP) and best-corrected visual acuity (BCVA). RESULTS: Seven eyes from 7 male aphakic patients with a mean age of 45 (range, 20-68)y were included in this study; the average follow-up time was 12 (9-15)mo. GT was performed in 2 eyes; membrane peeling (MP) and SOT in 2 eyes; and MP, SOT, and SB in 3 eyes. The mean pre- and post-operative IOP were 4.5 (range, 4.0±0.11 to 4.8±0.2) mm Hg and 9.9 (range, 5.6±0.17 to 12.1±0.2) mm Hg at 52wk (12mo), respectively. BCVA improved in six eyes; one eye still showed light perception, and no bulbi phthisis was observed. CONCLUSION: Endoscopy offers improved judgment and recognition and has an improved prognosis for chronic hypotony. Therefore, endoscopy can be an effective and promising operative technique for chronic traumatic hypotony management.     

Effects of Lysyl Oxidase Genetic Variants on the Susceptibility to Rhegmatogenous Retinal Detachment and Proliferative Vitreoretinopathy

Proliferative vitreoretinopathy (PVR), the most common cause of failure of rhegmatogenous retinal detachment (RD) surgery, is an anomalous scarring process related to ocular inflammation. Lysyl oxidase (LOX) is a copper-dependent amine oxidase that may play important roles in ocular tissue integrity. The aim of this study was to investigate whether polymorphisms in the LOX gene were associated with susceptibility to RD and PVR. We screened the promoter region of LOX gene and tested two previously reported polymorphisms (?22 G/C and 473 G/A) in RD patients with or without PVR and healthy controls. Data showed that prevalence of the -22CC genotype and -22C allele were significantly higher in the RD cases than in the control group after adjustment for sex and age (p?<?0.001 and p?<?0.001, respectively). Similarly, a significant difference was observed regarding LOX 473GA genotype and 473A allele between RD patients and healthy donors after adjustment for sex and age (p?=?0.005 and p?=?0.012, respectively). Also, when compared to RD cases without PVR, patients who developed PVR had significantly higher numbers of -22CC genotype and -22C allele (p?=?0.048 and p?=?0.003, respectively). These results indicated that LOX polymorphisms were associated with increased susceptibility to RD and PVR and suggest a potential correlation between LOX and ocular inflammation.     

Perlecan Knockdown in Metastatic Prostate Cancer Cells Reduces Heparin-binding Growth Factor Responses in vitro and Tumor Growth in vivo

Perlecan (Pln) is a major heparan sulfate proteoglycan (HSPG) of extracellular matrices and bone marrow stroma. Pln, via glycosaminoglycans in domains I and V, acts as a co-receptor for delivery of heparin binding growth factors (HBGFs) that support cancer growth and vascularization. Specifically, glycosaminoglycans bind HBGFs and activate HBGF receptors, including those for FGF-2 and VEGF-A. The contribution of Pln to prostate cancer growth was tested using a ribozyme approach to knockdown Pln expression levels. Transfection into the androgen-independent, bone targeted prostate cancer line, C4-2B, and efficient stable knockdown of Pln was demonstrated by quantitative PCR, immunohistochemistry and immunoblotting. Three individually isolated subclones with 75–80% knockdown in Pln mRNA, protein expression and secretion into ECM were used to study in vitro growth responses to FGF-2 and VEGF-A. While cells with normal Pln levels responded to both HBGFs, knockdown cells responded poorly. All lines responded to serum growth factors and IGF-I. Anchorage-independent growth assays showed reduced colony size and cohesiveness by all Pln deficient subclones compared to parental C4-2B cells. In vivo effects of Pln knockdown were measured by inoculating knockdown and control ribozyme transfected cell lines into athymic mice. A reduced growth rate, smaller tumor size, diminished vascularization and failure to elevate serum PSA characterized mice bearing Pln knockdown C4-2B cells. Poor vascularization correlated with reduced levels of VEGF-A secreted by Pln knockdown lines. We conclude that Pln is an essential ECM component involved in growth responses of metastatic prostate cancer cells to HBGFs deposited in local and metastatic microenvironment.     

Protective effects of lipoic acid-niacin dimers against blue light-induced oxidative damage to retinal pigment epithelium cells

AIM: To evaluate the protective effects of lipoic acid-niacin (N2L) dimers against blue light (BL)-induced oxidative damage to human retinal pigment epithelium (hRPE) cells in vitro. METHODS: hRPE cells were divided into a control group (CG), a BL group, an N2L plus BL irradiation group, an α-lipoic acid (ALA) plus BL group, an ALA-only group, and an N2L-only group. hRPE cellular viability was detected by performing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) bromide assays, and apoptosis was evaluated by annexin-V-PE/7-AAD staining followed by flow cytometry. Ultrastructural changes in subcellular organelles were observed by transmission electron microscopy. Reactive oxygen species formation was assayed by flow cytometry. The expression levels of the apoptosis-related proteins BCL-2 associated X protein (BAX), B-cell leukmia/lymphoma 2 (BCL-2), and caspase-3 were quantified by Western blot analysis. RESULTS: BL exposure with a light density of 4±0.5 mW/cm2 exceeding 6h caused hRPE toxicity, whereas treatment with a high dose of N2L (100 mol/L) or ALA (150 mol/L) maintained cell viability at control levels. BL exposure caused vacuole-like degeneration, mitochondrial swelling, and reduced microvillus formation; however, a high dose of N2L or ALA maintained the ultrastructure of hRPE cells and their organelles. High doses of N2L and ALA also protected hRPE cells from BL-induced apoptosis, which was confirmed by Western blot analysis: BCL-2 expression significantly increased, while BAX and caspase-3 expression slightly decreased compared to the CG. CONCLUSION: High-dose N2L treatment (>100 mol/L) can reduce oxidative damage in degenerating hRPE cells exposed to BL with an efficacy similar to ALA.