Polarized light microscopy

偏振光显微镜
  • 文章类型: Journal Article
    随着大多数哺乳动物骨骼的老化,它们通常变得更加脆弱。这种骨脆性状态通常与更均匀的胶原纤维取向(CFO)相关。与大多数哺乳动物不同,蝙蝠在其整个生命周期中保持机械能力的骨骼,但对翼骨内CFO的位置和年龄相关变化知之甚少。这项研究检验了以下假设:大型棕色蝙蝠(Eptesicusfuscus)中CFO的年龄相关变化与骨骼衰老的标准哺乳动物模型不同,C57BL/6实验室小鼠。我们使用来自定量偏振光显微镜(qPLM)的数据来比较长寿的大型棕色蝙蝠和年龄匹配的C57BL/6小鼠的CFO寿命。Eptesicus和C57BL/6小鼠表现出独特的CFO模式。与年龄相关的一致变化仅在Eptesicus的外皮质骨中明显,在老年个体中,骨组织更纵向排列,更各向异性。两个分类单元都显示出围绕髓腔的更横向定向的骨组织环。在Eptesicus,该组织代表了整个横截面的更大比例,并且比小鼠中的类似骨组织更清楚地螺旋排列(与骨长轴成45°排列)。蝙蝠翼骨在CFO各向异性和皮质骨内外区室的纵向方向上都显示出近远侧梯度。本研究为将来可能扩展的有体积和无体积哺乳动物的骨组织结构的定量评估奠定了方法学基础。
    As bones age in most mammals, they typically become more fragile. This state of bone fragility is often associated with more homogenous collagen fiber orientations (CFO). Unlike most mammals, bats maintain mechanically competent bone throughout their lifespans, but little is known of positional and age-related changes in CFO within wing bones. This study tests the hypothesis that age-related changes in CFO in big brown bats (Eptesicus fuscus) differ from those of the standard mammalian model for skeletal aging, the C57BL/6 laboratory mouse. We used data from quantitative polarized light microscopy (qPLM) to compare CFO across the lifespan of long-lived big brown bats and age matched C57BL/6 mice. Eptesicus and C57BL/6 mice displayed idiosyncratic patterns of CFO. Consistent age-related changes were only apparent in the outer cortical bone of Eptesicus, where bone tissue is more longitudinally arranged and more anisotropic in older individuals. Both taxa displayed a ring of more transversely oriented bone tissue surrounding the medullary cavity. In Eptesicus, this tissue represents a greater proportion of the overall cross-section, and is more clearly helically aligned (arranged at 45° to the bone long axis) than similar bone tissue in mice. Bat wing bones displayed a proximodistal gradient in CFO anisotropy and longitudinal orientation in both outer and inner cortical bone compartments. This study lays a methodological foundation for the quantitative evaluation of bone tissue architecture in volant and non-volant mammals that may be expanded in the future.
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  • 文章类型: Journal Article
    在这里,通过在玻璃基板上形成双链DNA骨架,设计了一种无标记的aptasensor,用于对曲霉毒素A(OTA)进行超灵敏定量,作为案例研究。双响应aptasensor的功能基础是液晶(LC)的垂直排列和SYBRGreenI(SGI)染料分子在双链DNA结构的碱基对之间的插入的扰动。OTA的存在通过从传感平台释放OTA特异性适体来分解DNA的双链结构,从而诱导光学和荧光响应的明显改变。基于偏振和荧光响应,aptasensor特别检测到OTA的超低水平为47.0E-9pM(0.047aM)和34.0E-3pM(34fM),分别。aptasensor监测了咖啡和葡萄饮料样品中的OTA。aptasensor为制造实时提供有希望的见解,成本效益高,和用于食品控制的便携式传感设备。
    Herein, a label-free aptasensor was designed through forming a double-stranded DNA skeleton on the glass substrate for ultrasensitive quantification of ochratoxin A (OTA) as a case study. The function fundament of the dual-responsive aptasensor was the perturbation of the vertical alignment of the liquid crystals (LCs) and intercalation of the SYBR Green I (SGI) dye molecules between the base pairs of the double-stranded DNA structure. The presence of OTA decomposed the double-stranded structure of DNA by releasing the OTA-specific aptamer from the sensing platform that induced an apparent alteration of the optical and fluorescent responses. The aptasensor specifically detected the ultra-low levels of OTA as 47.0E-9 pM (0.047 aM) and 34.0E-3 pM (34 fM) based on the polarized and fluorescent responses, respectively. The aptasensor monitored OTA in the coffee and grape drink samples. The aptasensor provides promising insight for manufacturing real-time, cost-effective, and portable sensing devices for food control usage.
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  • 文章类型: Journal Article
    自然资源保护局-凯洛格土壤调查实验室拥有一个大型的公开数据库,该数据库是从主要来自美国的土壤剖面中收集的土壤层的实验室分析。这些土壤特性包括来自土壤层的选定沙子和淤泥部分的矿物颗粒计数,通过偏振光显微镜(PLM)进行。来自7534个地点的超过20,000个部分的谷物计数提供了一个重要的参考,法医土壤检查员可以用来证实矿物物种的稀有性或普遍性。关于各种矿物的稀有性或普遍性的陈述为陪审团提供了额外的背景,以解释在试验框架内进行法医土壤比较的结果。还可以评估特定位置的谷物计数数据,以帮助土壤来源调查。对于在相关位置有谷物计数站点的情况。包括将这些应用于土壤证据数据的两个示例,一种是将土壤与矿物(红柱石)的稀有性联系起来,以在土壤比较中提供背景,另一种是在土壤来源调查中帮助缩小目标区域。
    The Natural Resources Conservation Service-Kellogg Soil Survey Laboratory has a large publicly available database of laboratory analyses of soil horizons collected from soil profiles largely from the United States. Among these soil properties are mineral grain counts from selected sand and silt fractions of soil horizons, performed by polarized light microscopy (PLM). These grain counts of over 20,000 fractions from 7534 sites provide a substantial reference that a forensic soil examiner could use to substantiate the rarity or commonness of a mineral species. The statement of the rarity or commonness of various minerals provide juries with additional context for the interpreting the results of a forensic soil comparison within the framework of a trial. The grain count data at specific locations can also be assessed to aid in soil provenance investigations, for cases where there are grain-counted sites in relevant locations. Two examples of application of these to data to soil evidence are included, one relating soil the rarity of a mineral (andalusite) to provide context in a soil comparison and one to aid in narrowing target regions in a soil provenance investigation.
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  • 文章类型: Case Reports
    二水合焦磷酸钙(CPPD)疾病,也被称为焦磷酸盐关节病或假性痛风,定义为关节软骨内的CPPD沉积。它于1962年首次描述。发生CPPD疾病的代表性部位包括最常见的膝关节,然后是腕关节.关节肿胀和疼痛是最常见的临床表现,典型的鉴别诊断是退行性关节炎。微观上,当在偏振光下检查时,样品显示出许多正双折射菱形晶体。
    我们介绍了一名70岁的女性,患有右侧疼痛性坐骨神经痛,并伴有患肢酸痛和笨拙。她的最终诊断是不寻常的腰椎硬膜外肿瘤假性疼痛,值得注意。椎板切除术后切除肿瘤CPPD沉积。随后,她的症状在术后减轻,无需更多镇痛药.她的神经功能得到了适当的恢复。
    这是一份罕见的报告,用于在不熟悉的腰椎硬膜外位置提供假性活动,这是一个意想不到的诊断。对于临床医生来说,对正在进行的疾病实体进行精确的初步诊断可能很困难,因为这种病理的临床表现与其他常见的退行性腰椎疾病相似。
    UNASSIGNED: Calcium pyrophosphate dihydrate (CPPD) disease, also known as pyrophosphate arthropathy or pseudogout, is defined as CPPD deposition within the articular cartilage. It was first described in 1962. The representative locations where CPPD disease occurs include the most common knee joint, followed by the wrist joint. Joint swelling and pain are the most common clinical presentations, and the typical differential diagnosis is degenerative arthritis. Microscopically, the specimen demonstrates numerous positively birefringent rhomboid shaped crystals when examined under polarized light.
    UNASSIGNED: We present a 70-year-old female with right painful sciatica accompanied by coexisting affected limb soreness and clumsiness. Her final diagnosis was unusual lumbar extradural tumoral pseudogout that was worth noticing. Tumoral CPPD deposition was excised after laminectomy. Subsequently, her symptoms were abated postoperatively without a need for more analgesics. Her neurological function was properly recovered.
    UNASSIGNED: This is a rare report to proffer pseudogout in an unfamiliar lumbar extradural location, which is an unexpected diagnosis. Making a precise tentative diagnosis for the ongoing disease entity might be difficult for the clinicians because the clinical manifestations of this pathology are similar to those of other common degenerative lumbar spinal diseases.
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  • 文章类型: Case Reports
    体外受精(IVF)周期取消的最常见原因是缺乏可用于胞浆内精子注射(ICSI)的优质配子。在这里,我们介绍了受阻塞性无精子症影响的夫妇的成功生育治疗以及对控制性卵巢刺激的次优反应。由于传统方法似乎无法有效克服双方的具体问题,有针对性的干预措施,即,(1)精子活力的药理增强和(2)偏振光显微镜(PLM)引导下ICSI时间的优化,用于挽救周期,仅回收未成熟的卵母细胞和不运动的睾丸精子。茶碱治疗有助于从冷冻保存的睾丸组织中选择可行的精子。当传统的刺激方案无法产生成熟的卵子时,采用非侵入性纺锤体成像将精子注射时间调整到体外挤出极体卵母细胞的成熟阶段。12个晚熟卵母细胞受精产生5个受精卵,都发育成胚泡。受精后第5天,将一个胚胎转移到子宫中,另外3个质量好的胚泡被玻璃化以备后用。怀孕导致足月分娩健康的孩子。该病例表明,应考虑超出标准IVF方案的个体化,以最大程度地提高预后不良患者用自己的配子实现妊娠的机会。
    The most common reason for in vitro fertilization (IVF) cycle cancelation is a lack of quality gametes available for intracytoplasmic sperm injection (ICSI). Here we present the successful fertility treatment of the couple affected by obstructive azoospermia combined with suboptimal response to controlled ovarian stimulation. Since the conventional approach appeared ineffective to overcome both partners\' specific problems, the targeted interventions, namely, (1) pharmacological enhancement of sperm motility and (2) polarized light microscopy (PLM)-guided optimization of ICSI time, were applied to rescue the cycle with only immature oocytes and immotile testicular sperm retrieved. The treatment with theophylline aided the selection of viable spermatozoa derived from cryopreserved testicular tissue. When the traditional stimulation protocol failed to produce mature eggs, non-invasive spindle imaging was employed to adjust the sperm injection time to the maturational stage of oocytes extruding a polar body in vitro. The fertilization of 12 late-maturing oocytes yielded 5 zygotes, which all developed into blastocysts. One embryo was transferred into the uterus on day 5 post-fertilization, and another 3 good quality blastocysts were vitrified for later use. The pregnancy resulted in a full-term delivery of a healthy child. This case demonstrates that the individualization beyond the standard IVF protocols should be considered to maximize the chance of poor-prognosis patients to achieve pregnancy with their own gametes.
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