小鼠肾脏发育中凋亡细胞的超微结构变化

1　材料和方法1 1　动物取昆明小鼠 ,雌雄比例 3∶1同窝饲养 ,以雌鼠阴道精栓出现为第 1日计算胎鼠胚龄。部分孕鼠分笼饲养 2 0日后 ,每天早八时观察分娩情况 ,新生仔鼠按生后计算日龄。选取 1 4、1 8日胎鼠各 4只 ,生后 1、7、1 4日龄仔鼠各 4只为观察对象。1 2　光镜和电镜标本制作　在冷操作条件下切开胎鼠和仔鼠腹部 ,取左肾于 2 5 %戊二醛内固定。胎鼠做全肾树脂包埋 ,仔鼠肾脏经肾门做矢状面切开 ,皮质和髓质分别进行树脂包埋。ＬＫＢ Ｖ型超薄切片机半薄连续切片 ,甲苯胺蓝染色 ,按Ｋｏｓｅｋｉ判断光镜下凋亡细胞后制超薄切片 ,…     

小鼠肾脏髓襻细段发育的超微结构

目的：探讨小鼠肾脏髓襻细段发生发育及逐渐成熟过程。方法：应用光镜半薄切片和电镜超薄切片观察小鼠肾脏髓襻细段发育过程中的超微结构变化。结果和结论：细段出现于胚胎后期,生后逐渐发育完善。上皮由立方细胞逐渐发育成扁平细胞过程中,细胞凋亡起着很大作用。细胞凋亡高峰时间发生在生后七天左右。超微结构观察发现生后细段完善主要位于长襻肾单位的细段。结论：细段在胚胎晚期出现,生后发育。在这一过程中,特别是在细胞构筑过程中细胞凋亡起着重要作用。     

小鼠肾脏发育中的细胞凋亡

目的：研究小鼠肾脏发育过程中的细胞凋亡规律及形态学特点,方法：应用光镜、电镜技术和TUNEL法分别对不同胚龄、生后日龄小鼠肾脏细胞凋亡进行了观察。结果：皮质凋亡细胞多出现在生肾区S小体之间和是肾小体内,凋亡高峰期在胚龄14－18d之间,髓质凋亡细胞出现在肾小鼠管上皮内,凋亡高峰期在生后7d 左右。超微结构观察可见皮质和髓质凋亡细胞主要表现为核固缩,染色质凝集,细胞皱缩。皮质和髓质凋亡细胞结局为,被邻近细胞吞噬,或脱落到肾小管腔内,结论：小鼠肾脏发育过程中确有细胞凋亡;皮质中细胞凋亡与生肾区的出现和肾小体发育完善有关,髓质中细胞凋亡与髓质中肾小管和集合小0管的有发育完善有关。     

小鼠胚胎肾细胞凋亡与胀亡的超微结构

目的:观察小鼠胚胎肾发育中细胞凋亡与胀亡的超微结构.方法:应用透射电子显微镜对不同胚龄大鼠肾进行了系统观察.结果:作为细胞程序性死亡的胀亡出现在发育的肾中,但与凋亡相比出现的频率不高.凋亡与胀亡的不同仅在于细胞质的表现.结论:在肾发育中细胞凋亡仍然为主要的程序性细胞死亡,胀亡只处于辅助地位.     

小鼠胚胎肾程序性细胞死亡行为的超微结构变化

目的:观察小鼠胚胎肾发育过程中程序性细胞死亡行为的超微结构变化.方法:应用透射电子显微镜技术对不同胚龄(E12、14、16、18 d)胎鼠的肾程序性细胞死亡进行系统观察.结果:在小鼠胚胎肾中,细胞凋亡多见,出现在肾发育的各个时期和各个结构中,程序性坏死和副凋亡少见,只出现在发育中的肾单位内.程序性细胞死亡的结局包括被吞噬、被血流带走和经尿液排出.结论:细胞凋亡、程序性坏死和副凋亡构成了小鼠胚胎肾发育过程中的程序性细胞死亡,以细胞凋亡为主,程序性坏死和副凋亡为辅.肾发育过程中程序性死亡的细胞尸骸经尿液排出是一个与肾结构特征有关的处理方式.     

肾脏细胞的凋亡

肾脏细胞的凋亡受许多细胞外部刺激、生存因子以及凋亡相关基因的调控，在肾脏发育过程中起重要作用，并参与许多肾脏疾病的发生     

小鼠出生后肾脏发育过程中的细胞增殖与凋亡

目的：观察小鼠出生后肾脏发育过程中增殖细胞核抗原(PCNA)的表达及细胞凋亡的特征,探讨出生后小鼠肾脏发育过程中细胞增殖与凋亡的规律及其关系。方法：应用免疫组织化学技术和原位末端标记法(TUNEL法)分别检测小鼠出生后1～70d肾脏中PCNA阳性的细胞和凋亡细胞。结果：小鼠出生后1～70d,皮质中的肾小体、肾小管、髓放线以及髓质中的肾小管和集合管的细胞,早期增殖活跃,随着肾脏发育成熟而表达逐渐减弱。同时,也存在着细胞凋亡现象,且凋亡高峰一般出现在增殖高峰之后。结论：细胞增殖与凋亡在小鼠生后肾脏发育的整个过程中普遍存在,生后1～7d细胞增殖旺盛,增殖高峰之后出现凋亡高峰,生后28～70d两者活动均减弱。     

人胚胎睾丸生殖细胞发育的组织学和超微结构研究

用光镜与电镜技术，对１５例７至２８周人胚胎睾丸生殖细胞的发育进行了研究。结果：（１）据时间，位置及形态结构特点，将生殖细胞的发育过程初步分为三个阶段，即原始生殖细胞阶段，生殖母细胞阶段和前的细胞阶段。其中前精原细胞阶段又经历了早，中，晚三上时期各期出现的时间有交错。（２）１４周是胚胎生殖细胞发育的一个重要时期。     

小鼠胚胎食管和肠上皮的体视学研究

目的 研究消化管上皮发生的影响因素。方法 用体视学法观测了１１～１７ｄＩＣＲ胎鼠连续切片中食管、十二指肠和结肠的管腔与上皮。部分切片用ＴＵＮＥＬ法标记细胞凋和对照。结果 ⑴３段消化管的管腔面积与上皮面积比值均随胎齿增加崦增高;上皮的财亡小体密度（ＤＡＢ）峰值均在分裂细胞密度（ＤＭＣ）峰值之后;上皮细胞密度与ＤＭＣ和ＤＡＢ间未见一致的相关性;⑵食管的ＤＡＢ峰值高于肠。食管上皮中凋亡小体分布于上皮各层     

小鼠肾脏发生发育的形态计量学研究

目的　探讨小鼠肾脏胚胎及生后发生发育规律。方法　应用光镜连续切片技术结合体视学定量分析方法。结果　皮质出现的时间为胚龄 14日 ,早期髓质结构出现在胚龄第 18日。皮质生肾区在生后 7日消失 ,生后 2 1日出现髓质内带。体现学分析结果说明 :髓质主要在生后发育完善 ,皮质体积在生后快速增大 ,肾小球的数目在生后 7日前发育完毕。结论　小鼠肾脏单位的发育是从胚胎后期 ,即胚龄 14日开始进行的 ,至生后 7日完成。胚胎 18日始到生后 2 1日是髓质发育期     

Ultrastructure of streptozotocin — induced renal tumours in mice

Streptozotocin-induced tumours in the kidneys of experimental animals have been shown to be histologically similar to human renal cell carcinoma. We report the ultrastructural features of renal tumours induced in 15 mice by a single intravenous bolus of 2.5% Streptozotocin administered in a dose of 250 mg streptozotocin/kg mouse body weight. Animals were sacrificed 232–361 days after the administration of streptozotocin. On examination both kidneys from each animal contained 1–4 dysplastic tubules and 1–3 discrete tumours per kidney. Twelve dysplastic proximal convoluted tubules showing varying degrees of epithelial atypia and nine tumours exhibiting either a papillary or solid architecture were examined. Dysplastic epithelial cells and tumours of papillary and solid type exhibited complex cell borders with well-developed junctional complexes. The majority of cells contained surface microvilli, and in some cells microvilli-lined intracytoplasmic lumina were observed. Occasional dysplastic epithelial cells and tumour cells contained double-membrane vesicles 120–200 nm in diameter. These were similar to the intracytoplasmic vesicles characteristic of human chromophobe renal cell carcinoma. Intracytoplasmic collections of glycogen granules and flocculant protein were identified in both dysplastic and neoplastic cells, and where prominent they resulted in compression of cytoplasmic organelles. Coated vesicles were commonly observed. These were free within the cytoplasm and were also seen budding from strands of rough endoplasmic reticulum. The distribution of these vesicles suggested a role in protein transport from the rough endoplasmic reticulum. It is concluded that while streptozotocin-induced renal tumours have some ultrastructural features in common with human chromophobe renal cell carcinoma, the overall ultrastructural morphology differs significantly from that described for the various histological types of human renal cell carcinoma.     

Ultrastructural development of the dorsal lateral geniculate nucleus of genetically microphthalmic mice

Summary The ultrastructure of the dorsal lateral geniculate nucleus (dLGN) of microphthalmic mice is described in affected white homozygotes (mi/mi) and their apparently normal grey littermates. In the dLGN of mi/mi animals populations of apparently normal axon terminals were observed, including some with flattened synaptic vesicles and other small terminals with round vesicles and dark mitochondria (RSD), possibly of cortico-thalamic origin, just as in normal mice. However, no typical large retinal endings with round vesicles and pale mitochondria (RLP) are visible. Instead they appear to be replaced by other large boutons with round vesicles and dark mitochondria (RLD). Eye enucleation does not cause degeneration of these RLD terminals. In apparently normal grey littermates RLP terminals are present and they degenerate when an eye is enucleated. But RLD endings are also found in these animals, and never degenerate after enucleation. The origin of the RLD terminals is unclear but seems not to be cortical. These findings are compared with those of Cullen and Kaiserman-Abramof (1976) in a different strain (ZRDCT-An) of anophthalmic mouse in which they found large replacement terminals similar to our RLD boutons.     

人肾小管上皮细胞necroptosis模型的构建

 目的：以体外培养的人肾小管上皮细胞（HK-2细胞）为靶细胞,构建肾小管上皮细胞凋亡样坏死（necroptosis）的模型。方法：采用肿瘤坏死因子 α (tumor nercosis factor α, TNF-α)诱导细胞凋亡,同时采用抗霉素A (antimycin A)耗竭ATP,构建肾小管上皮细胞凋亡的模型,并以caspase-8抑制剂苄氧羰酰-缬氨酰-丙氨酰-天冬氨酰-氟甲基酮(benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone, zVAD-fmk) 阻断凋亡,用necroptosis的特异性抑制剂necrostatin-1（Nec-1）阻断necroptosis,观察细胞在不同的处理下形态学的变化,同时检测细胞存活率及标志物微管相关蛋白1轻链3-Ⅱ（microtubule-associated protein 1 light chain 3-Ⅱ,LC3-Ⅱ）的表达。结果：（1）在TNF-α+zVAD- fmk+antimycin A处理1 h时细胞及细胞器膨胀,电镜下细胞膜碎裂,线粒体变圆、肿胀,嵴逐渐模糊,胞浆中出现大量自噬小体,而Nec-1预处理后细胞的坏死程度较对照组明显改善。（2）在TNF-α+zVAD-fmk+antimycin A 1 h实验组,Nec-1预处理后细胞的存活率显著增加（P<0.05）。（3）TNF-α+zVAD-fmk+antimycin A干预1 h实验组在Nec-1预处理后LC3-Ⅱ的表达量明显下降（P<0.05）。结论：凋亡环境中阻断凋亡可以诱导肾小管上皮细胞necroptosis,抑制剂Nec-1能特异性阻断肾小管上皮细胞发生坏死。     

Manipulation of necroptosis by Porphyromonas gingivalis in periodontitis development

To eliminate invading pathogens and keep homeostasis, host employs multiple approaches such as the non-inflammation associated-apoptosis, inflammation associated-necroptosis and pyroptosis, etc. Necroptosis is known as a highly pro-inflammatory form of cell death due to the release of massive damage-associated molecular patterns (DAMPs). For the first time, we reported that Porphyromonas gingivalis induced cellular necroptosis through receptor-interacting protein 1 (RIP1)/RIP3/mixed lineage kinase domain-like (MLKL) signaling pathway in monocytes. Necroptosis in THP-1 cells was induced by MLKL phosphorylation in vitro. P. gingivalis treated-THP-1 cells exhibited lower cell death rate with pretreatment of inhibitors RIP1 and MLKL, accompanied with attenuated TNF-α and IL-6 expressions. Moreover, the necroptosis risk was also reduced via gene silencing by RIP3 or MLKL in the P. gingivalis treated-THP-1 cell lines. We further explored P. gingivalis-induced necroptosis in animal models in vivo. Firstly, C57BL/6 mice were injected with P. gingivalis in the subcutaneous chamber model. Animals pretreated with MLKL inhibitor exhibited significantly enhanced P. gingivalis clearance; in addition, levels of TNF-α and IL-6 were notably decreased by 60% via MLKL inhibition. Secondly, P. gingivalis-induced periodontitis was utilized to investigate necroptosis related-periodontopathogensis. Positive staining of phosphorylated MLKL in mice periodontitis biopsies was detected to a higher degree, while larger amount of alveolar bone loss was observed in MLKL (−) group comparing to those in the MLKL (+) group. These findings may suggest that P. gingivalis play essential roles in necroptosis process during periodontitis, and our research may shed light on the further work on the related periodontopathogenesis investigation.     

Ultrastructural changes in the lung in Niemann-Pick type C mouse

The biochemical and morphological aspects of BALB/c mice with many features of the Niemann-Pick disease type C in man (NP-C mouse) have been studied extensively. However, the pulmonary pathology has not been studied extensively and we describe here some unique ultrastructural features of the lung in the NP-C mouse. Ultrastructurally, macrophages in younger mice contained osmiophilic dense granules and annulolamellar structures, but larger multilamellar concentric structures increased in the macrophages of older mice. In contrast, endothelial cells and type I pneumocytes showed membrane-bound bodies with dense granules and vesicular or vesiculogranular structures as well as amorphous materials. Type II pneumocytes were unremarkable throughout. Our study suggests that endothelial cells and type I pneumocytes are the major site of metabolic derangement resulting in pronounced morphological changes with granular and round membranous structures in the lungs of NP-C mouse. Alveolar macrophages with multilamellar concentric structures may be a result of disturbed disposal of surfactant material from type II pneumocytes rather than that from storage material of type I pneumocyte.     

Ultrastructural studies of malignant cells in fluids

An ultrastructural study was performed on 104 sequential fluids in which more than eight malignant cells per ten high-power fields were found by routine light microscopy. The study included fluids associated with mesotheliomas, melanomas, lymphomas, squamous-cell carcinomas, small-cell anaplastic (oat-cell) carcinomas, and adenocarcinomas. Electron microscopic examination reliably separated lymphoid from epithelial malignancies and benign from reactive and malignant mesothelial cell proliferations. It also suggested or identified a primary site for the adenocarcinomas. Ultrastructural examination of fluids can be a valuable adjunct to routine light microscopy of cytology specimens. No false-positive diagnoses were encountered. Sampling was the most significant limitation for this technique.     

Morphology of the synovium during its differentiation and development in the mouse knee joint

Summary The prenatal and postnatal development of the mouse knee joint was investigated by transmission and scanning electron microscopy. In the prenatal stage, following the appearance of a narrow intercellular cleft between two skeletal elements on the 16th fetal day, clefting extended into the lateral synovial mesenchyme. In some regions, the extension of the cleft was very rapid, but in a certain region (future fat pad region), it was somewhat slower. Macrophage-like cells appeared in the synovial mesenchyme on the 16th fetal day, and then increased in number, and were distributed as if they were clustering around the presumptive clefting zone in the future fat pad region on the 17th–18th fetal day. This suggests that macrophage-like cells may participate in joint development, as they phagocytize and remove some kinds of solid extracellular matrix, and facilitate the cleft extension. In the early postnatal stage, scanning electron microscopic observations showed that there were two different types of cell in the synovial lining. One of them exhibited a surface morphology corresponding to that of macrophages: a spherical cell body and numerous pseudopodia. The other type of cell exhibited various cell shapes with many cytoplasmic processes extending along the synovial surface.     

骨桥蛋白对小鼠体外受精及早期胚胎发育的影响

目的 探讨骨桥蛋白（OPN）对小鼠体外受精及早期胚胎发育的影响。方法 120只昆明雌鼠和30只雄鼠,采用体外受精、胚胎培养方法,将小鼠精子、卵子、原核期胚胎和2-细胞期胚胎分别用不同浓度的OPN抗体预处理,观察小鼠受精、卵裂以及早期胚胎发育情况。结果 不同浓度的OPN抗体分别预处理精子和卵子后,与对照组比较,受精率显著降低(P＜0.01)。OPN抗体预处理原核期胚胎后,0.01mg/L OPN抗体组的卵裂率较对照组低,但差异无显著性 (P =0.052),1.00mg/L OPN抗体组的卵裂率低于0.01mg/L 组（P ＜0.01）及0.10mg/L组（P ＜0.05）。不同浓度的OPN抗体预处理2-细胞胚胎后可抑制胚胎发育。1.00mg/L OPN抗体组的4-细胞率和8-细胞率与0.10mg/L OPN抗体组相比差异无显著性(P ＞0.05),但前者的囊胚形成率显著低于后者（P ＜0.01）。1.00mg/L OPN抗体组的4-细胞率、8-细胞率以及囊胚形成率均显著低于0.01mg/L OPN抗体组（P ＜0.01）。结论 OPN可促进小鼠的受精和早期胚胎发育。     

An Insight into Ultrastructural and Morphological Alterations of Platelets in Neurodegenerative Diseases

Platelets are evinced as a systemic tool in a variety of disorders, including neurodegenerative diseases. Evidence suggests that variations in the ultrastructure and morphology of platelets and related organelles are involved in the pathophysiology of diabetes, cancer, HIV/AIDS, cardiovascular and neurological diseases. Due to structural alterations of platelets in many diseases, it is informative to discuss the ultrastructural and morphological discrepancies of platelets in contemporary medical research. The present review reveals the usefulness of ultrastructural study in better understanding of the disease patterns and may help to improve the treatment regimes.     

An electron microscopic study of periderm cell development in mouse limb buds

Summary Development of periderm cells covering fore-and hindlimb buds of mouse em`ryos was observed by scanning and transmission electron microscopy at half day intervals from day 9.5 to 12.5 of gestation (vaginal plug=day 0).At day 9.5, the epidermis is single layered. Occasional periderm cells are present at day 10.5. By day 11.5 a complete layer of periderm cells has covered the entire limb bud.By scanning electron microscopic observation, periderm cells covering the apical ectodermal ridge (AER) are characterized by a small surface size and an elongated polygonal shape with the long axis parallel to the antero-posterior contour of the apical rim. Periderm cells covering the dorsal and ventral surfaces of the limb bud are relatively large and have a polygonal surface shape.The periderm covering the apical tip reflects well the developmental state of the AER. Hence, it is possible to estimate the development of the AER by observing the surface features of the apical periderm by scanning electron microscopy.This work was supported by Scientific research Grant No. 348082 from the Ministry of Education, Japan