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PurposeHigh resolution spectral domain optical coherence tomography (SD-OCT) was used to assess the anterior segment structure parameters in healthy South Asian children.Methods108 eyes of 54 healthy children ≤ 16 years were recruited after a thorough eye exam. The anterior segment analysis was be done by Optopol Revo 80 high resolution SD-OCT. Central corneal thickness (CCT), Angle opening distance (AOD), Anterior chamber (AC) angle, Trabecular iris space area (TISA), Trabecular iris angle (TIA), iris thickness at 2 mm, internal AC diameter and lens vault were evaluated.ResultsMean age was 11.38 years. Mean IOP was 13.63 mmHg, mean axial length, 22.82 mm, mean spherical equivalent, -0.14 D, mean CCT, 532.6 µm and mean CDR was 0.31. The mean internal AC diameter was 11609.15 µm. The nasal and temporal AC angles was 53.54° and 50.37°, respectively [P = .033]. The nasal and temporal AOD500 were 0.9 mm and 0.85 mm, respectively [P = .629]. The nasal and temporal AOD750 were 1.21 mm and 1.06 mm, respectively [P = .583]. The nasal TIA was 41.75°; the temporal TIA; 40.24° [P = .325]. The nasal TISA500 was 0.33 mm2; the temporal TISA500, 0.31 mm2 [P = .012]. The nasal TISA750 was 0. 59 mm2; the temporal TISA750, 0.56 mm2 [P = .746]. The nasal iris thickness at 2 mm was 483.54 µm; the temporal iris thickness, 505.8 µm [P = .273]. The mean lens vault was -519.58 µm.ConclusionsOur study data depicts the normal anterior segment parameters in healthy Pakistani children.  相似文献   
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ObjectiveOur aim was to study photodecomposition, photomutagenicity and cytotoxicity of retinyl palmitate (RP), a principal storage form of vitamin A in humans and animals, under He–Ne laser photoirradiation. Moreover, the effect of different concentrations and timing protocol of antioxidants on photodynamic therapy (PDT) is contradictory, so the effect of RP (as antioxidant) on the PDT cytotoxicity was studied.MethodsPhotomutagenicity was tested by Ames test. Photodecomposition was studied by UV–vis spectroscopy. Cytotoxicity was measured with MTT-assay. Moreover, the effect of PDT, using hematoporphyrin derivatives (HpD) as photosensitizer under He–Ne laser irradiation (10 J/cm2), was studied on HeLa cells either with or without RP (1–100 μM) which incubated with the cells for short or long incubation period (1 h or 24 h) prior to PDT.ResultsNo photodecomposition of RP alone was obseved whereas there is a little photodecomposition of RP only in presence of HpD under irradiation with He–Ne laser. Moreover, no photomutagenicity was observed in Salmonella typhimurium strains under laser irradiation in presence or absence of HpD. RP alone (1–100 μM) significantly decrease the viability of HeLa cells. Laser irradiation of HeLa cells pre-incubated with RP alone for 24 h showed further significant decrease in viability of the cells. While RP incubations for 1 h before PDT had slight effect on the cells, 24 h incubation before PDT enhanced the cytotoxicity of PDT on HeLa cells.ConclusionsRP can be used 24 h before PDT to enhance its effects. RP is not mutagenic under irradiation with He–Ne laser.  相似文献   
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 目的:探证sprouty4(SPRY4)蛋白对角质形成细胞增殖及分化的影响。方法:以人永生化表皮细胞株HaCaT细胞作为实验对象,实验组HaCaT细胞采用基因敲降技术进行SPRY4蛋白抑制物的转染,对照组HaCaT细胞不作任何处理。运用实时荧光定量PCR技术(RT-qPCR)检测实验组与对照组中sprouty4蛋白对HaCaT细胞分化指标Involucrin、CK1与CK10的影响,运用CCK-8实验检测HaCaT细胞的增殖功能。结果:RT-qPCR结果显示,实验组HaCaT细胞中SPRY4基因敲降成功,敲降率约为94.75%。与对照组相比,实验组HaCaT细胞中分化指标Involucrin、CK1与CK10表达水平降低;CCK-8实验结果显示,与对照组相比,实验组HaCaT细胞增殖能力增强。结论:SPRY4蛋白表达下降对细胞增殖起到促进作用,对细胞分化起到抑制作用。  相似文献   
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寻常痤疮是一种毛囊皮脂腺单位的炎症疾病,在青少年中的发病率高达85%,发病机制与雄激素、皮脂分泌、嗜脂性微生物感染、免疫-炎症反应等密切相关。本文从炎症信号通路、皮脂分泌通路方面,综述与痤疮相关的信号转导通路。  相似文献   
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ObjectivesThe purpose of this study was to investigate the potential correlation between lactate dehydrogenase A (LDHA) and AMP-activated protein kinase (AMPK) and their clinicopathologic significance in breast cancer.Materials and MethodsWestern blot and qRT-PCR were used to detect the expression levels of LDHA and AMPK in eight breast cancer lines and eight breast cancer tissues. In addition, LDHA and AMPK were detected by immunohistochemistry (IHC) using breast cancer tissue microarrays (TMAs) of 112 patients. The association between LDHA and AMPK expression levels was statistically analyzed. So were the prognostic roles and clinicopathologic significances in breast cancer.ResultsThe expression levels of LDHA and AMPK were relatively higher in triple-negative breast cancer (TNBC) cell lines than in non-triple-negative breast cancer (NTNBC) cell lines. LDHA and AMPK were also further up-regulated in TNBC tissues than in NTNBC tissues. Correlation analysis showed a positive correlation between LDHA and AMPK expression levels. Expression of LDHA and AMPK were significantly correlated with TNM stage, distant metastasis, Ki67 status and survival outcomes of patients. Patients with both positive expression of LDHA and AMPK showed shorter overall survival (OS) and disease-free survival (DFS).ConclusionsThese findings improve our understanding of the expression pattern of LDHA and AMPK in breast cancer and clarify the role of LDHA and AMPK as promising prognostic biomarkers for breast cancer.  相似文献   
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Inflammation involving the helper T cell 17 (Th17) subset of lymphocytes has been implicated in a number of diseases that affect the nervous system. As the canonical cytokine of Th17 cells, interleukin 17A (IL-17A) is thought to contribute to these neuroimmune interactions. The main receptor for IL-17A is expressed in many neural tissues. IL-17A has direct effects on neurons but can also impact neural function via signaling to satellite cells and immune cells. In the central nervous system, IL-17A has been associated with neuropathology in multiple sclerosis, epilepsy syndromes and ischemic brain injury. Effects of IL-17A at the level of dorsal root ganglia and the spinal cord may contribute to enhanced nociception during neuropathic and inflammatory pain. Finally, IL-17A plays a role in sympathetic axon growth and regeneration of damaged axons that innervate the cornea. Given the widespread effects of IL-17A on neural tissues, it will be important to determine whether selectively mitigating the damaging effects of this cytokine while augmenting its beneficial effects is a possible strategy to treat inflammatory damage to the nervous system.  相似文献   
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