Effectiveness of cross polarized light and fluorescence diagnosis for detection of sub‐clinical and clinical actinic keratosis during imiquimod treatment

Please cite this paper as: Effectiveness of cross polarized light and fluorescence diagnosis for detection of sub‐clinical and clinical actinic keratosis during imiquimod treatment. Experimental Dermatology 2010; 19: 641–647. Background: During treatment of actinic keratosis (AK) lesions with imiquimod sub‐clinical lesions often become visible. It is, however, unclear whether these sub‐clinical lesions would be detectable beforehand. Objective: The aim of this pilot study was to compare two techniques, cross polarized light photography (CPL) and fluorescence diagnosis (FD) using methyllevulinic acid and illumination with Wood’s lamp for their ability to detect sub‐clinical lesions. These findings were also compared with biopsy results taken before and after treatment with imiquimod 5% cream or vehicle. Methodology: Twelve patients with at least five clinically visible AK lesions in a single contiguous 20 cm² area on the head were recruited. Patient eligibility was determined at the screening visit, when they were randomized to treatment. The randomization was 3:1, active to vehicle (nine treated with imiquimod, three with vehicle cream) for a total duration of 24 weeks (six clinic visits). Patients were assessed for baseline AK lesion counts (clinical and sub‐clinical) at the screening visit and final counts at week 20. Results: The number of clinically observed AK lesions was significantly lower at week 12 and week 20 compared with baseline following imiquimod treatment versus vehicle. The number of counted lesions were significantly higher using the CPL method compared with clinical counting with imiquimod treatment at baseline (8.3 ± 3.4 vs 5.8 ± 1.3; P = 0.027) and week 20 (4.8 ± 2.4 vs 3.0 ± 1.7; P = 0.02) but not in the vehicle group. The FD lesion counting method did not show a significant increase in the number of detected lesions compared with clinical analysis in the imiquimod and placebo groups but when comparisons were performed using pooled data (treatments and visits combined) the results were significant. Conclusion: The number of sub‐clinical and clinical AK lesions detected during treatment with imiquimod can be better demonstrated using the methods of CPL and FD, but statistical significance was reached only using the CPL method. This is only a preliminary study with a small number of patients and as a result it is difficult to conclude both statistical and clinical significance. However, results were encouraging and indicate that larger studies are needed to demonstrate the relevance of these two new methods for improved detection of clinical and especially sub‐clinical AK lesions.     

A quantitative assessment of the human skin surface using polarized light digital photography and its dermatologic significance

Background: Quantitative and objective investigations of parallel‐polarized light (PPL) photography for dermatologic purposes are scarce. Objective: To determine the significance of quantitative analysis of PPL photography to develop objective measurement methods of skin surface characteristics. Method: For PPL photography, a digital camera, a light‐emitting diode illuminator, and polarizing filters were arranged and kept constant. We analyzed the PPL photography images of the glabella, the medial aspect of the forearm, and the posterior aspect of the lower leg, and measured the CIELAB values. A dermatologist evaluated the clinical severity of the actual photographed sites with respect to glossiness and dryness. These clinical severities were compared statistically with the CIELAB values. Results: According to the correlation analysis, the L^* value was negatively correlated with dryness (r=?0.29869, P=0.0047) and glossiness (r=?0.35367, P=0.0185). Conclusion: The method used in this study is applicable to the quantitative evaluations of other dermatologic diseases or conditions, especially in relation to skin surface changes.     

基于正交双偏振光的无创血糖检测方法及初步实验研究

针对光电外差探测法和直接探测法偏振光无创血糖检测方法存在的缺点,本文提出了一种新的正交双偏振光无创血糖检测方法,将正交双偏振光通过血糖引起的微小偏振角的变化转化为两个方向上偏振光的能量差,由相关原理高灵敏锁相放大器检测,控制法拉第线圈电流补偿血糖引起的偏转角变化,利用血糖浓度与法拉第线圈电流的线性关系,计算获得血糖浓度。以LX-20全自动生化分析仪测得的数据作为标准进行对比实验,葡萄糖溶液实验的相关系数为0.9777,血清实验的相关系数为0.952。研究表明本方法具有较高的检测灵敏度和准确度,为研制实用的新型无创血糖检测仪打下了基础。     

Layered structure of saccular aneurysms assessed by collagen birefringence

Abstract

Cerebral aneurysms are composed principally of collagen, a birefringent protein which is responsible for withstanding the forces of blood pressure. The known correlation between collagen birefringence and its mechanics provides the basis for using polarizing microscopy to evaluate the strength of collagen, layer by layer across the aneurysmal wall. In order to obtain better quantitative measurements, several birefringent enhancement stains were investigated. We concluded that sirius red F3B, at a concentration of 0.05% in saturated picric acid, is an excellent stain to enable measurement of both birefringence and directional organization on the same tissue sections. Six aneurysms from autopsy, fixed at 120 mmHg, and one surgical specimen were cut at 4 ixm to provide sets of tangential sections. The polarizing optics emphasizes the multi-layered structure of the aneurysmal wall with the mean fiber alignments distinguishing one layer from another. Birefringence measurements showed that the outer third of the wall had mainly higher strength collagen, although not as high as nearby artery adventitia. The inner layers of the aneurysms had intermediate values, similar to the artery media and subendothelium. Our results are consistent with a model of aneurysmal enlargement that requires the reorganization of higher strength outer fibers while new collagen is added to the inner layers. [Neurol Res 1999; 21: 618-626]     

线偏振光在眼科医学中的应用研究

本文提出了一种利用正交线偏振光来进行眼科检查，从而改善诊断结果的简便而有效的方法，文中简述了工作原理，并给出线偏振光在检查角膜内皮，视网膜神经纤维层以及青光眼视野检查三方面应用的结果。     

Determination of regional VA/Q by hyperpolarized 3He MRI.

Alveolar ventilation/perfusion ratio (VA/Q) is a key parameter in functional imaging of the lung. Herein, regional VA/Q was calculated from regional values of alveolar partial pressure of oxygen (PAO2) measured by hyperpolarized 3He gas MRI (HP 3He MRI). Yorkshire pigs (n = 7, mean weight = 25 kg) were paralyzed and maintained under isoflurane anesthesia. Animals were placed into a birdcage coil, then transferred to the bore of a 1.5 T MRI unit. Prior to imaging, animals were manually ventilated with room air for 5 min, then a 3He gas mixture was administered during breathhold and imaging performed. PAO2 was measured based on the decay rate of 3He signal. Subjects' blood gas concentrations were measured and these values and PAO2 values entered into a system of four equations with four unknowns. Calculated VA/Q values were analyzed by preparing frequency distributions for the entire lung and compared to VA/Q frequency distributions previously established in the literature as normal using other diagnostic techniques. Distributions were consistent with those in the literature, indicating that HP 3He MRI may be an accurate, quantitative, noninvasive, and nonradioactive method for acquiring VA/Q for small regions of the lung.     

Pro‐inflammatory M1 macrophages promote Osteogenesis by mesenchymal stem cells via the COX‐2‐prostaglandin E2 pathway

Bone fractures are among the most common orthopaedic problems that affect individuals of all ages. Immediately after injury, activated macrophages dynamically contribute to and regulate an acute inflammatory response that involves other cells at the injury site, including mesenchymal stem cells (MSCs). These macrophages and MSCs work in concert to modulate bone healing. In this study, we co‐cultured undifferentiated M0, pro‐inflammatory M1, and anti‐inflammatory M2 macrophages with primary murine MSCs in vitro to determine the cross‐talk between polarized macrophages and MSCs and their effects on osteogenesis. After 4 weeks of co‐culture, MSCs grown with macrophages, especially M1 macrophages, had enhanced bone mineralization compared to MSCs grown alone. The level of bone formation after 4 weeks of culture was closely associated with prostaglandin E2 (PGE2) secretion early in osteogenesis. Treatment with celecoxib, a cyclooxygenase‐2 (COX‐2) selective inhibitor, significantly reduced bone mineralization in all co‐cultures but most dramatically in the M1‐MSC co‐culture. We also found that the presence of macrophages reduced the secretion of osteoprotegerin (OPG), the decoy RANKL receptor, suggesting that macrophages may indirectly modulate osteoclast activity in addition to enhancing bone formation. Taken together, these findings suggest that an initial pro‐inflammatory phase modulated by M1 macrophages promotes osteogenesis in MSCs via the COX‐2‐PGE2 pathway. Understanding the complex interactions between macrophages and MSCs provide opportunities to optimize bone healing and other regenerative processes via modulation of the inflammatory response. This study provides one possible biological mechanism for the adverse effects of non‐steroidal anti‐inflammatory drugs on fracture healing and bone regeneration. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2378–2385, 2017.

     

Role of nitric oxide in modulation of afferent impulses in cutaneous branches of somatic nerves by polarized light

Subcutaneous injection of L-NAME inhibited afferent impulse activity inn. ischiadicus andn. saphenus and abolished the increase in this activity induced by stimulation of mechanoreceptors after skin irradiation with polarized light with various spectral characteristics. Subsequent subcutaneous injection of sodium nitroprusside restored the pattern of afferent impulse activity in these nerves during repeated skin irradiation with polarized light. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 130, No. 8, pp. 140–143, August, 2000     

基于实时景深扩展-大图影像拼接与偏振光显微鉴别技术的柴胡及其4种混淆品的生药学研究

目的 基于实时景深扩展-大图影像拼接与偏振光显微鉴别技术,对柴胡2个基原品种柴胡Bupleurumchinense或狭叶柴胡B.scorzonerifolium及4种市场常见混淆品（竹叶柴胡B.marginatum、藏柴胡B.marginatumvar.stenophyllum、锥叶柴胡B. bicaule、大叶柴胡B. longiradiatum）的性状、微性状及显微鉴别特征进行系统的对比研究,为柴胡的鉴别及质量控制提供科学依据。方法 性状鉴别研究采用性状及微性状鉴别法,显微鉴别研究采用普通光明场与偏振光暗场对比观察法,结合实时景深扩展成像、大图影像拼接技术,拍摄获取药材组织横切面全息彩色影像图。结果 获取了柴胡及其混淆品的性状及微性状影像数据,首次获取了该类药材横切面显微鉴别普通光及偏振光全息彩色影像数据。对柴胡2个基原品种及其4种混淆品进行了系统的生药学研究。与《中国药典》2020年版相比,性状鉴别补充研究了精细微性状鉴别特征,对柴胡药材根或根茎的上、中、下部位横切面进行对比观察,确定了柴胡药材根或根茎上部横切面组织构造最具特征性,为最佳的横切面显微研究部位。结论 可以综合应用性...