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1.
目的:利用图像拼接方法对不同程度干眼症患者角膜上皮基底神经丛进行定量分析,探讨其变化规 律。方法:横断面研究。选取2021年4—10月于山西省眼科医院门诊就诊的干眼症患者共91例(91眼), 其中轻度干眼34例、中度干眼33例、重度干眼24例,同时征集正常健康志愿者作为对照组共27例 (27眼),所有受检者均选择右眼数据分析,对所有受检者分别行常规眼科检查、眼表综合分析仪检 查、角膜共焦显微镜检查后,运用Photoshop CC 2018图像处理软件合成大范围角膜上皮基底细胞层 下神经丛(SNP)结构拼图,截取以涡状结构为中心的、大小为700 μm×700 μm的图像进行分析,结 合Image J图像分析系统计算得出图像中神经纤维总长度(NFL),将所得数据通过图像大小与像素之 间的换算关系计算出单位面积(1 mm2)的神经纤维总长度值即神经纤维密度值(mm/mm2)。采用单 因素方差分析对各组数据进行比较,同时对两两之间进行LSD多重比较;采用Pearson线性相关分析 各组角膜SNP密度与眼表综合分析检查中各项指标间的相关性。结果:4组间性别、年龄比较差异 无统计学意义。对照组SNP密度为(22.71±6.19)mm/mm2,轻度干眼组为(28.58±5.19)mm/mm2, 中度干眼组为(28.17±4.71)mm/mm2,重度干眼组为(5.98±7.32)mm/mm2,4组SNP密度总体差异 有统计学意义(F=88.10,P<0.001);轻、中、重度干眼SNP密度与对照组差异均有统计学意义(均 P<0.001),轻度干眼组与中度干眼组间差异无统计学意义,重度干眼组与轻、中度干眼组间差异均 有统计学意义(均P<0.001)。干眼症患者角膜SNP密度与泪河高度、睑板腺缺失面积评分(上+下)及 眼表充血评分之间无明显相关性,与非侵入性泪膜破裂时间呈正相关(r=0.51,P<0.001),与脂质层 分级、角膜荧光素钠染色分级呈负相关(r=-0.30,P=0.004;r=-0.68,P<0.001)。结论:角膜SNP密 度及形态改变与干眼症的严重程度分级有关,可作为临床评估干眼程度的有效指标。  相似文献   
2.
Introduction and Aim: The indiscriminate use and adverse effects of the main conventional antifungal agents compromise the effectiveness of treating vulvovaginal candidiasis (VVC), mainly caused by the species Candida albicans. This study evaluated the effectiveness of photodynamic therapy (PDT) and the in vitro and in vivo anti-candida potential of the hypericin (HYP)-loaded nanostructured lipid carriers (NLC). Materials and Methods: Empty NLC and NLC-HYP were characterized by the dynamic light scattering technique and transmission electron microscopy to evaluate the average particle size distribution and its morphologies. The in vitro inhibition photodynamic effect of the systems was tested to reduce the planktonic viability of C. albicans. The therapeutic assay photodynamic of the systems was performed to treat VVC in mice. Results: Empty NLC and NLC-HYP presented values of average hydrodynamic diameter, polydispersity index, and ζ-potential from 136 to 133 nm, 0.16 to 0.22, and -18 to -30 mV, respectively, on day 30. Microscopically, the systems showed spherical morphologies and nanoscale particles. Furthermore, in the in vitro inhibition assay, the treatment of PDT with NLC-HYP (NLC-HYP+) showed a significant reduction of the C. albicans planktonic viability compared to YNB negative control after 5 min of LED light irradiation. In the in vivo therapeutic assay, the antifungal group (vaginal antifungal cream) and NLC-HYP+ evaluated in the dark and by PDT, respectively, had a significant log10 reduction in fungal burden compared to the infected group on day 8 of the VVC treatment. Conclusion: Due to the in vitro and in vivo anti-candida potential, PDT-mediated systems can be an effective strategy in VVC therapy.  相似文献   
3.
Here, we review the development, morphology, genes, and proteins of claws in reptiles. Claws likely form owing to the inductive influence of phalangeal mesenchyme on the apical epidermis of developing digits, resulting in hyperproliferation and intense protein synthesis in the dorsal epidermis, which forms the unguis. The tip of claws results from prevalent cell proliferation and distal movement along most of the ungueal epidermis in comparison to the ventral surface forming the subunguis. Asymmetrical growth between the unguis and subunguis forces beta-cells from the unguis to rotate into the apical part of the subunguis, sharpening the claw tip. Further sharpening occurs by scratching and mechanical wearing. Ungueal keratinocytes elongate, form an intricate perimeter and cementing junctions, and remain united impeding desquamation. In contrast, thin keratinocytes in the subunguis form a smooth perimeter, accumulate less corneous beta proteins (CBPs) and cysteine-poor intermediate filament (IF)-keratins, and desquamate. In addition to prevalent glycine–cysteine–tyrosine rich CBPs, special cysteine-rich IF-keratins are also synthesized in the claw, generating numerous  S S bonds that harden the thick and compact corneous material. Desquamation and mechanical wear at the tip ensure that the unguis curvature remains approximately stable over time. Reptilian claws are likely very ancient in evolution, although the unguis differentiated like the outer scale surface of scales, while the subunguis might have derived from the inner scale surface. The few hair-like IF-keratins synthesized in reptilian claws indicate that ancestors of sauropsids and mammals shared cysteine-rich IF-keratins. However, the number of these keratins remained low in reptiles, while new types of CBPs function to strengthen claws.  相似文献   
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5.
Superficial amorphization and re-crystallization of silicon in <111> and <100> orientation after irradiation by femtosecond laser pulses (790 nm, 30 fs) are studied using optical imaging and transmission electron microscopy. Spectroscopic imaging ellipsometry (SIE) allows fast data acquisition at multiple wavelengths and provides experimental data for calculating nanometric amorphous layer thickness profiles with micrometric lateral resolution based on a thin-film layer model. For a radially Gaussian laser beam and at moderate peak fluences above the melting and below the ablation thresholds, laterally parabolic amorphous layer profiles with maximum thicknesses of several tens of nanometers were quantitatively attained. The accuracy of the calculations is verified experimentally by high-resolution transmission electron microscopy (HRTEM) and energy dispersive X-ray spectroscopy (STEM-EDX). Along with topographic information obtained by atomic force microscopy (AFM), a comprehensive picture of the superficial re-solidification of silicon after local melting by femtosecond laser pulses is drawn.  相似文献   
6.
Liver steatosis is a common complication of chronic hepatitis C virus (HCV) infection, which can result in accelerated liver fibrosis development, especially in patients infected with genotype 3a. The precise mechanisms of HCV-induced liver steatosis remain unclear, but it is often posited that increased intracellular lipid accumulation is the underlying cause of steatosis. To study experimentally how HCV infection in human liver derived cells by different genotypes and subtypes might affect lipid accumulation, we performed detailed cytofluorimetric and microscopy analyses of intracellular lipid droplets (LDs) in relation to the viral Core and to cell endoplasmic reticulum proteins. Following culture infection with HCV genotype 1a, 2a, 2b, 2c, and 3a strains, we found variable levels of intracellular LDs accumulation, associated to the infecting strain rather than to the specific genotype. Although two genotype 3a strains showed high levels of lipid accumulation, as previously observed, some strains of other genotypes displayed a similar phenotype. Moreover, the analyses of LDs size, number, and shape indicated that the apparent increase in lipid accumulation is due to an increase in the overall number rather than in the size of droplets. Finally, differences in total lipid content across genotypes did not correlate to differences in Core distribution nor Core levels. In conclusion, our study provides a quantitative in-depth analysis of the effect of HCV infection on LDs accumulation in cell-culture.  相似文献   
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8.
The microvascular anatomy of the non-lobulated liver of adult Xenopus laevis was studied by scanning electron microscopy of vascular corrosion casts. Hepatic portal veins and hepatic arteries entered hepatic lobes at the hiluses, hepatic veins left at these sites. Intraparenchymal, hepatic portal veins branched up to 10 times before terminal portal venules supplied liver sinusoids. Hepatic arteries closely followed portal vessels. Arteriolar side branches formed anastomoses with close by portal venules (arteriolar-portal anastomoses; APAs), liver sinusoids (arteriolar-sinusoidal anastomoses; ASAs), and peribiliary plexus vessels. Distally, hepatic arteries anastomosed with terminal portal venules having >100 μm in diameter. Liver sinusoids formed a dense three-dimensional network displaying signs of non-sprouting and sprouting angiogenesis evidenced by “holes” and blind ending tapering cast vascular structures (sprouts), respectively. Sinusoids drained via efferent hepatic veins. Right and left hepatic veins drained into the posterior caval vein. Locally, a dense honeycomb-like 3D-meshwork of resin structures was found around terminal portal venules and hepatic arteries. These networks were fed by hepatic arterioles and drained into adjacent terminal portal venules. As their morphologies differed significantly from sinusoids and they were found at sites where diffuse lymphoid tissue is described, we are convinced that they represent the vasculature of diffuse lymphoid tissue areas. Frequencies and diameter ratios of hepatic portal venules versus hepatic arterioles anastomosing with the former (APAs) implicate that the arterial supply contributes to the oxygenation of parenchymal and stromal cells rather than to a significant increase in blood flow towards hepatic sinusoids.  相似文献   
9.
10.

Objectives

Fibromyalgia is a condition which exhibits chronic widespread pain with neuropathic pain features and has a major impact on health-related quality of life. The pathophysiology remains unclear, however, there is increasing evidence for involvement of the peripheral nervous system with a high prevalence of small fiber pathology (SFP). The aim of this systematic literature review is to establish the prevalence of SFP in fibromyalgia.

Methods

An electronic literature search was performed using MEDLINE, EMBASE, PubMed, Web of Science, CINAHL and the Cochrane Library databases. Published full-text, English language articles that provide SFP prevalence data in studies of fibromyalgia of patients over 18years old were included. All articles were screened by two independent reviewers using a priori criteria. Methodological quality and risk of bias were evaluated using the critical appraisal tool by Munn et al. Overall and subgroup pooled prevalence were calculated by random-effects meta-analysis with 95% CI.

Results

Database searches found 935 studies; 45 articles were screened of which 8 full text articles satisfied the inclusion criteria, providing data from 222 participants. The meta-analysis demonstrated the pooled prevalence of SFP in fibromyalgia is 49% (95% CI: 38–60%) with a moderate degree of heterogeneity, (I2=?68%). The prevalence estimate attained by a skin biopsy was 45% (95% CI: 32–59%, I2=?70%) and for corneal confocal microscopy it was 59% (95% CI: 40–78%, I2=?51%).

Conclusion

There is a high prevalence of SFP in fibromyalgia. This study provides compelling evidence of a distinct phenotype involving SFP in fibromyalgia. Identifying SFP will aid in determining its relationship to pain and potentially facilitate the development of future interventions and pharmacotherapy.  相似文献   
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