豆状核变性患者之肝细胞培养及超微结构观察

目的 :建立肝豆状核变性的肝细胞原代培养模型 ,并采用超微制片技术获细胞超微结构 ,使对该疾病的研究能达到细胞超微结构水平。方法 :对肝豆状核变性患者采用外科手术取肝组织 ,应用Ⅳ型离体胶原酶消化分离法获得肝组织细胞悬液。再用差速离心机将肝细胞和其他细胞分离提纯后对肝细胞原代培养 7～ 10天。收集培养细胞 ,利用超微制片技术获肝细胞的超微结构。结果 :取肝豆状核变性患者肝细胞 ,通过台酚兰染色示即时存活率可达95 %。肝细胞培养 7天后细胞存活率可达 90 % ,细胞纯度达 90 % ,细胞收集量达 5× 10 5个。用超薄切片技术制片 ,在…     

失血性休克下犬重要器官超微结构的观察

犬失血性休克五小时,在电镜下可见心、肺、肝、小肠和肾等重要器官出现明显的结构损伤,具体变化如下:心肌纤维水肿,核周胞浆增多,肌原纤维粗细不均,间距变大,肌丝分散并有溶解;闰盘变直,有不同程度的肌丝解离;肌质网和横小管扩张;线粒体凝集变性,基质局灶性空泡化,外膜破裂,偶见巨大线粒体(图1)。肺泡内含水肿液;肺泡Ⅰ型细胞肿大,线粒体肿胀,肺泡Ⅱ型细胞增多,嗜锇性板层小体减少或变空,肺泡隔内毛细血管内皮细胞肿胀,基膜变薄,腔内有血小板、粒细胞聚集及微血栓形成(图2)。肝细胞索断裂,肝细胞游离在极度扩张的Disse间隙和肝窦内,肝细胞变大变圆,表面微绒毛消失,细胞膜破裂,线粒体高度肿胀,嵴断裂或消失,可见巨大线粒体,内含副结晶,不少肝细胞核浓缩,     

还精煎对老年小鼠肝细胞亚微结构的影响

本实验用纯种小白鼠分成三组:正常对照组、老年组、还精煎组。动物迅速杀死后,取肝组织用电镜常规技术作固定、脱水、包埋和切片,铅轴染色,DXA_4—10电镜观察。对照组动物肝细胞超微结构正常,肝细胞多为三角形,含1—2个核,核膜清楚、核红周围有核红相随染色质围绕,异染色质分布在核膜内层,常染色质均匀分布于核液内。细胞质内有丰富的细胞器及内含物,线粒体嵴清楚,粗面内质网平行排列成群,滑面内质网分布于细胞质中,高尔基体分布于核附近及胆小管处,此外尚有溶酶体、微粒、肝糖元、少量脂滴及色素。老年组动物肝细胞的核及线粒体的亚微结构和核糖体的含量有显著变化。细胞的核仁失去典型的核仁丝结构,出现核仁病     

供肝热和冷保存性缺血性损伤的超微结构观察

目的:探索供肝热、冷缺血对肝组织的超微结构影响,并讨论与某些手术并发症发生的关系.方法:从我院实施的67例原位肝移植病例中选择9例移植前供肝活检组织病理学检查无明显形态学改变、供肝者临床肝功能正常、肝炎病毒及巨细胞病毒检测均为阴性的供肝组织进行透射电镜观察.结果:在供肝中央静脉周围肝细胞质中常有较多吞噬溶酶体,少数肝细胞核出现浅的切迹,胞质中线粒体明显减少,部分线粒体肿胀.少部分毛细胆管腔扩大,微绒毛肿胀,微绒毛芯中微丝束减少或消失.部分小叶间胆管上皮细胞凋亡,管腔中含凋亡小体及细胞碎片.少数小叶间静脉内皮细胞肿胀,胞质空泡变性,甚者内皮细胞脱离管腔,细胞质膜断裂.结论:供肝毛细胆管和小叶间胆管上皮细胞的损伤是保存性损伤引起轻度胆汁淤积的主要因素.而小叶间胆管周围小血管内皮细胞的损伤可能是导致小叶间胆管上皮细胞凋亡的直接原因.小叶间静脉内皮细胞的损伤使血管壁平滑度受损,血流减缓,加重肝细胞的缺氧.     

凋亡神经元线粒体超微结构的形态计量学分析

目的:观察并分析人大脑皮层凋亡神经元线粒体超微结构的形态计量学变化.方法:取21例脑外科手术患者的额叶大脑皮质超薄切片中的正常神经元和凋亡神经元的电镜照片各80张,分为对照组与凋亡组.采用形态计量学方法对两组神经元的细胞体、细胞核、线粒体及细胞质基质灰度进行分析.结果:与正常神经元相比,凋亡神经元线粒体的体密度、面密度、数密度、比膜面明显增大(P＜0.01),比表面无明显改变(P＞0.05),线粒体基质与细胞质基质灰度之差明显增大(P＜0.01).结论:凋亡神经元线粒体未发生明显肿胀或增生,但其内膜和嵴的面积明显增加,基质密度降低.     

人肝细胞癌的超微结构研究

本文共收集临床诊断为肝癌患者的手术或肝穿肝组织7例,经组织学诊断,6例为原发性肝癌,1例为胆管癌,常规制备超薄切片标本,国产DXB2—12型电镜观察,结果分析如下: 一、核的改变及其病理学意义:肝癌细胞核呈明显多形态性,核/浆比例大,核质密度高,核仁肿大多样。但分化程度不同,核的这些结构特征表现程度亦异,增殖迅速的低分化癌,胞核更不规则,胞质细胞器更少,高分化癌则与正常肝细胞相似。表明癌细胞增殖速度、分化程度及恶性程度与形态特征存在一定关系。二、癌细胞质细胞器分布异常及其意义:中分化型肝癌形态变化更为复杂,癌细胞的主要细胞器〈如线粒体、     

人表皮细胞系PcaSE-1的超微形态定量分析

PcaSE-1细胞系是一个来源于硬腭癌病人大腿皮肤的上皮细胞系。我们用立体学的方法,从超薄切片上细胞的结构数据,计算细胞三维空间的超微结构参数,得到胞浆中线粒体、溶酶体、高尔基体、微丝及基质的体密度,粗面内质网及线粒体外膜的面密度,溶酶体及线粒体的大小及数密度,桥粒的大小及面数密度。还根据二次电子图象,得出细胞游离面上微绒毛的大小及面数密度;根据冷冻复型图象,得出核孔的大小及面数密度。此外,根据半薄切片,得出核浆比及核的大小,并得到平均细胞的各种结构参数。     

急性黄疸性肝炎的超微结构观察

肝是机体重要器官之一,肝细胞受损直接影响其代谢,合成,分泌和解毒等功能。急性黄疸性肝炎病程较短,病变较重,它不仅具有急性肝炎的症状,体征及化验的异常,且血清总胆红素超过3.0mg/d1时,明显发生黄疸。本文观察了7例急性黄疸性肝炎的材料,现将超微病变总结如下:观察结果:急性黄疸性肝炎低倍镜下改变为广泛的肝细胞变性、坏死。变性以胞浆疏松化和气球样变最为普遍,致使肝细胞排列紊乱肝窦受压变窄,肝细胞内有胆汁淤积,电镜下肝细胞水肿,图1,2胞质疏松,粗面内质网呈囊状扩张,且有不同程度的脱颗粒,滑面内质网也扩张成池,线粒体呈浓缩基质电子密度增高,嵴无法辨认,糖原颗粒减少。个别肝细胞膜破裂,细胞核模糊不清,核仁偏位(图1),或核固缩(图2),细胞核常染色质丰富(图3),肝细胞间及窦周隙内充满大量胶原纤维并形成致密的细胞壁(图2～3)。在汇管部有的淋巴细胞突起     

电镜与电子探针在诊断早期Wilson病的应用

电镜与电子探针在诊断早期Ｗｉｌｓｏｎ病的应用许念桂张淑安徐锡萍谭爱玲彭降祥（湖南医科大学电镜室，长沙４１００７８）Ｗｉｌｓｏｎ病又称肝豆状核变性，系铜代谢障碍所致的常染色体隐性遗传病，由于铜在人体组织中过量聚积，特别在肝、脑、肾和角膜聚积特多，过量的...     

固本降脂丸治疗高血脂症的超微结构观察

动脉粥样硬化(A、S)为国内外常见心血管疾患之一,动脉粥样硬化疾患随年龄增加而有增多趋势。目前认为(A、S)是多种因素的综合作用,而高血脂为非常重要的危害因素。中医中药对于防治高血脂症,经过长期实验,发掘出不少有效的中药,我们采用补肾填精复方固本降脂丸治疗高血脂症,经临床应用有一定的疗效。本文通过动物实验研究及应用电镜技术,观察固本降脂丸对高血脂症的疗效。高血脂组大白鼠肝脏有显著的超微结构变化,肝细胞内有大小不等的脂滴,线粒体轻度变性,细胞质密度减低。中药治疗组大白鼠肝脏超微结构有不同程度改善,并接近正常。实验结果表明,固本降脂丸能纠正脂质代谢紊乱,改善肝细胞的超微结构。     

弱精症病人精子线粒体的电镜观察

为了解弱精症精人精子线粒体的超微结构变化,本文对10例弱精症病人,4例健康人（年龄28－37）精液稀释后离心,常规电镜制片,透射电镜观察。结果表明：弱精症患者除了存在精子大小、形态和核形异常外,同时精子内线粒体发生了超微结构的病理性改变,表现为：一是在精子头部或核有病变的精子,其属部线粒体存在数量和分布的异常,出现双层、三层重叠,并发生脊间隙增宽;二是线粒体肿胀、膜电子密度减低、脊间隙扩张并形成微囊;三是出现畸形或巨形线粒体。本文提出对男性不育病人进行精液电镜检查,了解线粒体的超微结构变化,对明确诊断和临床治疗有一定价值。     

High‐Fidelity Trapping of Spatial–Temporal Mitochondria with Rational Design of Aggregation‐Induced Emission Probes

High‐fidelity trapping of mitochondrial dynamic activity is critical to value cellular functions and forecast disease but lack of spatial–temporal probes. Given that commercial mitochondria probes suffering from low photostability, aggregation‐caused quenching effect, and limited signal‐to‐noise ratio from fluorescence “always on” in the process of targeting mitochondria, here, the rational design strategy of a novel aggregation‐induced emission (AIE) molecular motif and unique insight into the high‐fidelity targeting of mitochondria is reported, thereby illustrating the relationship between tailoring molecular aggregation state and mitochondrial targeting ability. This study focuses on how to exactly modulate the hydrophilicity and the aggregated state for realizing “off‐on” fluorescence, as well as matching the charge density to go across the cell membrane for mitochondrial targeting. Probe tricyano‐methylene‐pyridine (TCM‐1) exhibits an unprecedented high‐fidelity feedback on spatial–temporal mitochondrial information with several advantages such as “off‐on” near‐infrared characteristic, high targeting capacity, favorable biocompatibility, as well as excellent photostability. TCM‐1 also produces reactive oxygen species in situ for image‐guided photodynamic anticancer therapy. Through unraveling the relationship between tuning molecular aggregation behavior and organelle‐specific targeting ability, for the first time, a unique guide is provided in designing AIE‐active probes to explore the hydrophilicity and membrane potential for targeting subcellular organelles.     

Nonparametric algorithm for local frequency estimation of multidimensional signals

Local frequency (LF) estimation of multidimensional (md) signals is considered. The md-Wigner distribution (WD) is used as the LF estimator. The LF is estimated based on the positions of the WD maxima. A nonparametric algorithm for the LF estimation is developed. It is based on the intersection of confidence intervals rule. This algorithm produces an adaptive window size in the WD which gives almost minimal mean squared error of the estimate. A simplified version of this algorithm is developed, with the starting estimate being produced with the WD of one-dimensional signals. Theory is illustrated in examples.     

A 2D Wigner Distribution-based multisize windows technique for image fusion

We present a scheme for image fusion based on a 2D implementation of the Wigner Distribution (WD) combined with a multisize windows technique. The joint space–frequency distribution provided by the WD can be managed as a measure of saliency that indicates which regions among different sources (channels) should be preserved. However such a saliency measure varies significantly according to the local analysis (window) in which the WD is calculated. Hence, large windows provide high resolution and robustness against possible noise present in channels and small windows provide accurate localization. The multisize windows technique combines the saliency measures of different windows taking advantage of the benefit contributed by each size. The performance assessment was conducted in artificial multifocus images under different noise exposures as well as real multifocus scenarios.     

Starvation induces the formation of giant mitochondria in gastric parietal cells of guinea pigs

Mitochondria occasionally increase in size in response to metabolic injury. Numerous studies have reported giant mitochondria in patients with various diseases and animals with metabolic injuries, but there are few reports on giant mitochondria in normal cells under physiological conditions. Here, we report giant mitochondria in normal gastric parietal cells. Stomachs of guinea pigs fed freely, fasted or fasted and then injected with histamine were processed for electron microscopy. Giant mitochondria >2 microm in the diameter of their major axis were observed in resting-type parietal cells in the gastric glands of animals fasted for 60-72 h, whereas acid-secreting-type parietal cells found in those fed ad libitum did not contain giant mitochondria. Giant mitochondria showed unusual structures, especially in their cristae: they contained closely packed, tubular and concentric cristae as well as amorphous and pleomorphic inclusion bodies in their matrix. We observed giant mitochondria consisting of several segments, suggesting the fusion of several normal-sized mitochondria. Histamine injection decreased in a frequency of giant mitochondria in accordance with a decrease in a frequency of resting-type parietal cells. This is the first report of giant mitochondria in gastric parietal cells under physiological or near physiological conditions. Gastric parietal cells might be a good model for examining mitochondrial fusion and fission in a physiological state accompanied by the morphological change of the cells in the membrane system from an acid-secreting to resting type.     

线粒体改变在超微结构病理诊断中的作用

线粒体是细胞生理功能必需的细胞器。线粒体DNA的缺陷是许多临床疾病的基础，许多不同疾病都具有非特异性的线粒体的病变。本文主要综述了在不同病理情况下，线粒体主要的结构变化，以及其在超微结构病理诊断中的作用。     

Efficient and accurate analysis of mitochondrial morphology in a whole cell with a high-voltage electron microscopy

Mitochondria in all eukaryotes are essential organelles responsible for adenosine triphosphate synthesis, calcium homeostasis and steroidogenesis. Because the structure and distribution of mitochondria are highly diverse depending on their function and cellular conditions, it is important to develop a rapid and accurate method to assess their morphology. In this study, we visualize whole mitochondria in cultured cells using high-voltage electron microscopy (HVEM). Compared with conventional transmission electron microscopic approaches, the present method does not require thin sectioning and thus requires less time for image acquisition and processing. Furthermore, compared with fluorescence-based light microscopic approaches, our method provides more accurate size information. Thus, we propose that HVEM is a useful tool for rapid and accurate analysis of mitochondrial morphology and distribution in a cell.     

Rational Engineering of a Mitochondrial-Mimetic Therapy for Targeted Treatment of Dilated Cardiomyopathy by Precisely Regulating Mitochondrial Homeostasis

Dilated cardiomyopathy (DCM) is a leading cause of heart failure and the most common indication for heart transplantation. Currently, there is still an unmet clinical need in effective therapies for DCM. Herein a mitochondrial-mimetic therapy capable of efficiently targeting the heart, cardiomyocytes, and myocardial mitochondria as well as effectively regulating mitochondrial homeostasis for targeted treatment of DCM is reported. A bioactive conjugate TPT is first synthesized by integrating three functional moieties onto a scaffold, which can assemble into small-size nanomicelles (i.e., TPTN). Intravenously delivered TPTN efficiently accumulates in the heart and mainly localizes in cardiomyocytes and myocardial mitochondria of DCM mice, thereby alleviating DCM. Mechanistically, TPTN inhibits intracellular oxidative stress, alleviates mitochondrial injury, improves mitochondrial dynamics, regulates mitochondrial oxidative phosphorylation, and reduces calpain-1 and NLRP3 inflammasome activation, thus restoring mitochondrial homeostasis and inhibiting adverse cardiac remodeling. By packaging TPTN into outer mitochondrial membrane-derived vesicles, a mitochondrial-mimetic therapy is engineered, which displays significantly enhanced three-level targeting capability to the heart, cardiac cells, and myocardial mitochondria, thereby affording notably potentiated therapeutic effects in DCM mice. Accordingly, the three-level targeting mimetics is promising for targeted treatment of DCM. The findings provide new insight into rational design of precision therapies for mitochondrial dysfunction-associated diseases.     

Dual‐Stage‐Light‐Guided Tumor Inhibition by Mitochondria‐Targeted Photodynamic Therapy

In this paper, a self‐delivery system PpIX‐PEG‐(KLAKLAK)₂ (designated as PPK) is fabricated to realize mitochondria‐targeted photodynamic tumor therapy. It is found that the PPK self‐delivery system exhibited high drug loading efficacy as well as novel capacity in generation of intracellular reactive oxygen species (ROS). This study also indicated that the photochemical internalization effect of the photosensitizer protoporphyrin IX (PpIX) under a short time light irradiation improved the cellular internalization of PPK. On the contrary, PPK could target to the subcellular organelle mitochondria due to the presence of proapoptosis (KLAKLAK)₂ peptide. Importantly, the in situ generation of ROS in mitochondria enhanced the photodynamic therapy efficacy under another long time irradiation, leading to significant cell death with decreased mitochondrial membrane potential. Besides, relative high tumor accumulation, minimal systemic cytotoxicity and efficacious long‐term tumor inhibition in vivo are also confirmed by using a murine model. All these results demonstrated the self‐delivery system PPK with a dual‐stage light irradiation strategy is a promising nanoplatform for tumor treatment.